To see the other types of publications on this topic, follow the link: Tea root tissues.
Journal articles on the topic 'Tea root tissues'
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the top 50 journal articles for your research on the topic 'Tea root tissues.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Browse journal articles on a wide variety of disciplines and organise your bibliography correctly.
1
Xiong, Hua Bin, Chang Qun Duan, Deng Gao Fu, Ming Zhi Liang, Kai Yan, and Feng He. "Accumulation and Distribution of As in Different Tissues of Camellia sinensis." Advanced Materials Research 848 (November 2013): 350–53. http://dx.doi.org/10.4028/www.scientific.net/amr.848.350.
Full textAbstract:
Arsenic is an important toxic substance in soil contamination, research of As accumulation and distribution in Camellia sinensis can explore adopting mechanism of tea plant to toxic substance and breeding of strong resistance varieties. In the research As content in root, stem and leaf part was detected on the condition of different concentration stress. The results showed that with the increase of treatment concentration relative change rate of tea plant was remarkable ascend. But, in root difference of five materials was most distinguished in low dose. In leaf when As concentration arrived 50 and 100mg/kg, difference of them was highly significant. Relative change rate from stem was not significant difference in all treatment.
2
Lv, Ya Min, Jing Ping Yang, Jun Yu He, Xing Zhao, and Xin Yi Ye. "Effects of Phosphate Fertilizers on Bioavailable Lead in Tea Garden Soil and Lead Absorption and Accumulation by Tea Plants." Applied Mechanics and Materials 651-653 (September 2014): 231–35. http://dx.doi.org/10.4028/www.scientific.net/amm.651-653.231.
Full textAbstract:
Tea is a widely consumed beverage in the world and an important economic crop in China. However in recent years tea gardens were increasingly contaminated by heavy metals such as lead (Pb). Root uptake of Pb could contribute significantly to Pb accumulation in tea leaves due to the strong acidity of tea garden soils. To reduce the Pb bioavailability and absorption by tea plants, a pot experiment was conducted to evaluate the effects of 3 phosphate fertilizers separately with a normal application rate in the field of 0.2 g (P2O5) ·kg-1soil and a high application rate of 0.5 g (P2O5) ·kg-1soil on bioavailable Pb in tea garden soil and Pb absorption and accumulation by tea plants. Results showed that application of calcium magnesium phosphate significantly increased soil pH by up to 0.6 units from 3.50 to 4.13. Phosphate fertilizers resulted in an increase of bioavailable Pb concentration in tea garden soil under our experimental conditions. Pb concentration in tissues of the tea plants under different phosphate fertilizer treatments followed the order of root>stem>leaf. Calcium magnesium phosphate with a high application rate of 0.5 g P2O5·kg-1soil decreased Pb concentrations of roots, stems and leaves of tea plants significantly. For one phosphate fertilizer, Pb absorption in tea plants under high application rate was much lower than it under normal application.
3
Bai, Peixian, Kang Wei, Liyuan Wang, Fen Zhang, Li Ruan, Hailin Li, Liyun Wu, and Hao Cheng. "Identification of a Novel Gene Encoding the Specialized Alanine Decarboxylase in Tea (Camellia sinensis) Plants." Molecules 24, no. 3 (February 1, 2019): 540. http://dx.doi.org/10.3390/molecules24030540.
Full textAbstract:
Theanine, a unique amino acid in Camellia sinensis, accounts for more than 50% of total free amino acids in tea and has a significant contribution to the quality of green tea. Previous research indicated that theanine is synthesized from glutamic acid (Glu) and ethylamine mainly in roots, and that theanine accumulation depends on the availability of ethylamine which is derived from alanine (Ala) decarboxylation catalyzed by alanine decarboxylase (AlaDC). However, the specific gene encoding AlaDC protein remains to be discovered in tea plants or in other species. To explore the gene of AlaDC in tea plants, the differences in theanine contents and gene expressions between pretreatment and posttreatment of long-time nitrogen starvation were analyzed in young roots of two tea cultivars. A novel gene annotated as serine decarboxylase (SDC) was noted for its expression levels, which showed high consistency with theanine content, and the expression was remarkably high in young roots under sufficient nitrogen condition. To verify its function, full-length complementary DNA (cDNA) of this candidate gene was cloned from young roots of tea seedlings, and the target protein was expressed and purified from Escherichia coli (E. coli). The enzymatic activity of the protein for Ala and Ser was measured in vitro using ultra-performance liquid chromatography coupled with mass spectrometry (UPLC-MS). The results illustrated that the target protein could catalyze the decarboxylation of Ala despite of its high similarity with SDC from other species. Therefore, this novel gene was identified as AlaDC and named CsAlaDC. Furthermore, the gene expression levels of CsAlaDC in different tissues of tea plants were also quantified with quantitative real-time PCR (qRT-PCR). The results suggest that transcription levels of CsAlaDC in root tissues are significantly higher than those in leaf tissues. That may explain why theanine biosynthesis preferentially occurs in the roots of tea plants. The expression of the gene was upregulated when nitrogen was present, suggesting that theanine biosynthesis is regulated by nitrogen supply and closely related to nitrogen metabolism for C. sinensis. The results of this study are significant supplements to the theanine biosynthetic pathway and provide evidence for the differential accumulation of theanine between C. sinensis and other species.
4
Zhang, Hua, Yakang Song, Zhenglei Fan, Jianyun Ruan, Jianhui Hu, and Qunfeng Zhang. "Aluminum Supplementation Mediates the Changes in Tea Plant Growth and Metabolism in Response to Calcium Stress." International Journal of Molecular Sciences 25, no. 1 (December 30, 2023): 530. http://dx.doi.org/10.3390/ijms25010530.
Full textAbstract:
Tea plants are more sensitive to variations in calcium concentration compared to other plants, whereas a moderate aluminum concentration facilitates the growth and development of tea plants. Aluminum and calcium show a competitive interaction with respect to the uptake of elements, consequently exerting physiological effects on plants. To further explore these interactions, in this study, we used the solution culture method to treat tea plants with two calcium concentrations (0.8 mM and 5.6 mM) and three aluminum concentrations (0 mM, 0.4 mM, and 1 mM). We then determined the influence of the combined treatments on root growth and quality compound accumulation in the tissues by a combination of phenotype, gene expression, and metabolite analyses. Moderate aluminum supplementation (0.4 mM) alleviated the inhibition of root growth caused by high calcium stress. High calcium stress significantly inhibited the accumulation of most amino acids (e.g., Glutamic acid, Citulline, and Arginine) and organic acids (e.g., a-ketoglutaric acid) in the roots, stems, and leaves, whereas aluminum deficiency significantly increased most amino acids in the roots and leaves (except Serine, Alanine, and Phenylalanine in the roots and Ser in the leaves), with a more than two-fold increase in Arg and Lysine. High calcium stress also induced the accumulation of secondary metabolites such as epigallocatechin gallate and procyanidin in the roots, whereas aluminum supplementation significantly reduced the contents of flavonol glycosides such as quercetin, rutin, myricitrin, and kaempferitrin, as well as caffeine, regardless of calcium concentration. Aluminum supplementation reversed some of the changes in the contents of leaf metabolites induced by calcium stress (e.g., 4-dihydroquercetin, apigenin C-pentoside, phenethylamine, and caffeine). Overall, calcium stress caused severe growth inhibition and metabolic disorders in tea plants, which could be reversed by aluminum supplementation, particularly in maintaining the root tips and the accumulation of secondary metabolites. These results provide a theoretical basis for improving calcium-aluminum nutrient management to promote tea plant growth and quality.
5
Magambo, M. J. S., and Kimani Waithaka. "The Effect of Pruning at Different Heights on Yields, Dry Matter Production and Partitioning in Clonal Tea (Camellia Sinensis) in Kenya." Experimental Agriculture 21, no. 1 (January 1985): 67–72. http://dx.doi.org/10.1017/s0014479700012266.
Full textAbstract:
SUMMARYDry matter production and partitioning in old clonal tea bushes pruned and maintained at different heights were investigated. New tissues (leaves, new branches and small roots) consti- tuted a small fraction of the total dry matter in all bushes pruned and initially maintained at 70, 40, 25 and 10 cm high, 36 months after pruning. Leaf/frame dry matter ratio was larger and the shoot/root and frame/root ratios were smaller in the bushes initially maintained at 10 cm than in the bushes maintained at other heights. Yields per unit area of the plucking surface were greatest in the smallest bushes initially maintained at 10 cm in 42 months of recording but on the basis of the available space they were greatest in the large bushes initially maintained at 70 cm.
6
Zhang, Ruirui, Xiaoyue Lun, Yunhe Zhao, Yu Zhang, Yan Cao, Xiangzhi Zhang, Meina Jin, Zhengqun Zhang, and Xiuxiu Xu. "RNAi-Mediated Interference with EonuGR1 Affects the Recognition of Phenylacetaldehyde by Empoasca onukii Matsuda (Hemiptera: Cicadellidae)." Agronomy 13, no. 9 (August 25, 2023): 2221. http://dx.doi.org/10.3390/agronomy13092221.
Full textAbstract:
Empoasca onukii Matsuda is a primary pest of the tea plant Camellia sinensis (L.) O. Ktze that severely influences the production and quality of tea products. Gustatory receptors (GRs) are an indispensable part of the E. onukii chemosensory machinery as members of the G-protein coupled receptor family. Insect odor and gustatory receptors are consumingly sensitive and selective sensory receptors to search for foraging, mates, and spawning sites. In this study, the gustatory receptor EonuGR1 was cloned and analyzed bioinformatically, and the expression levels of EonuGR1 in diverse tissues of E. onukii were tested via qRT-PCR. The behavioral response of E. onukii to volatile compounds was determined via RNA interference and Y-tube olfactometer assays to investigate the role of EonuGR1 in the olfactory recognition of E. onukii. The coding sequence length of EonuGR1 was 1062 bp, and the length of the protein encoded by EonuGR1 was 40.52 kD. The highest interference efficiency was observed after 3 h of dsEonuGR1 treatment via root soak treatment. Moreover, the response rates to phenylacetaldehyde at concentrations of 10 and 0.1 µL/mL were significantly downregulated in E. onukii. The responses to phenylacetaldehyde at concentrations of 10 and 100 µL/mL showed a significant decrease after dsEonuGR1 treatment for 12 h in E. onukii. In conclusion, EonuGR1 was highly expressed in the abdomen and functioned in olfactory recognition of the tea plant volatile phenylacetaldehyde by E. onukii. Overall, EonuGR1 has the potential as a gene target for the design of effective control strategies against E. onukii.
7
N. Ramos, L. P., L. S. D. Nascimento, J. S. Lima, C. B. M. Farias, V. S. Mello, and I. V. Kasburg. "Evaluation of the cytotoxic and genotoxic effect of garlic (Allium sativum L.) root cells after exposure to contaminant solution." Scientific Electronic Archives 13, no. 3 (March 1, 2020): 6. http://dx.doi.org/10.36560/1332020823.
Full textAbstract:
Water contamination is much more common than imagined, because it is practically impossible today to have an ecosystem that has not suffered directly or indirectly from humans. Studies with the aim of genotoxicity and mutagenesis use bioindicators as the basis of tests, the most used are from the Allium ssp family. When we mention cytogenetic damage, the intensity depends mainly on the degree of exposure, quantity, chemical nature and of the possible combinations between the contaminants, also influenced by the characteristics and conditions of the environment in which the organisms considered bioindicators are submitted. The present work has the objective of analyzing the cytotoxic, genotoxic and mutagenic effects induced by contaminating material that cause chromosomal alterations by means of mitotic index analysis using as bioindicator Allium sativum (garlic). The experiment was carried out at the Laboratory of Cytogenetics and Culture of Vegetable Tissues at the University of the State of Mato Grosso (UNEMAT) at the Alta Floresta Campus - MT. The soil was collected and stored separately using 200 grams of each sample with three treatments: surface, 20 cm and 40 cm deep, making a tea with 200 ml of distilled water and then measuring the pH. Using a direct method where the bioindicator is submitted directly to the tea solution, awaiting the emission of roots, and the indirect method, where the bioindicator is submitted first, the stimulation of root formation for 72 hours and then is submitted to contaminating solution. The plates readings to observe the interior of the cell using crushing techniques were performed in 24, 48 and 72 hours of experiment (indirect method) and 24 hours (direct method, also measuring the roots). With the results, we can state that the material used as pollutant (soil sample) has a cytotoxic and genotoxic potential in the bioindicator material, presenting high potential in the cell cycle induction, provoking various chromosomal aberrations.
8
Hu, Xiao-Fei, Fu-Sheng Chen, Michael L. Wine, and Xiang-Min Fang. "Increasing acidity of rain in subtropical tea plantation alters aluminum and nutrient distributions at the root-soil interface and in plant tissues." Plant and Soil 417, no. 1-2 (April 24, 2017): 261–74. http://dx.doi.org/10.1007/s11104-017-3256-3.
Full text
9
Gościniak, Anna, Magdalena Paczkowska-Walendowska, Agnieszka Skotnicka, Marek A. Ruchała, and Judyta Cielecka-Piontek. "Can Plant Materials Be Valuable in the Treatment of Periodontal Diseases? Practical Review." Pharmaceutics 13, no. 12 (December 17, 2021): 2185. http://dx.doi.org/10.3390/pharmaceutics13122185.
Full textAbstract:
Periodontal diseases are one of the most significant challenges in dental health. It is estimated that only a few percent of the worldwide population have entirely healthy teeth, and according to WHO, oral diseases may affect up to 3.5 billion people worldwide. One of the most serious oral diseases is periodontitis, an inflammatory disease affecting periodontal tissues, caused by pathogenic bacteria and environmental factors such as the ageing population, abuse of tobacco products, and lack of adequate oral hygiene due low public awareness. Plant materials are widely and successfully used in the management of many conditions, including periodontitis. Plant materials for periodontitis exhibit antibacterial, anti-inflammatory, antioxidant activities and affect the periodontium structure. Numerous studies demonstrate the advantages of phytotherapy for periodontitis relief and indicate the usefulness of Baikal skullcap root, Pomegranate fruit peel and root cortex, Tea leaves, Chamomile flowers, Magnolia bark, Blackberry leaves and fruits, Cranberry fruits and Lippia sidoides essential oil. This review aims to analyze the use and applicability of selected plant materials in periodontitis management since it is of paramount importance to evaluate the evidence of the traditionally used plant materials in light of continuously growing interest in phytotherapy and its adjuvant role in the treatment of periodontitis.
10
Li, Xiaoshuang, Tingting Zhang, Li Jiang, and Guizhi Fan. "Evaluation of Suitable Reference Genes for Quantitative Real-Time PCR in Various Tissues of Apocynum venetum." Genes 15, no. 2 (February 11, 2024): 231. http://dx.doi.org/10.3390/genes15020231.
Full textAbstract:
Apocynum venetum L. is an economically valuable plant with tolerance to drought and salinity. Its leaves are utilized in tea production and pharmaceuticals, while the stem bark serves as a high-quality fiber material. To gain insights into the gene expression patterns of A. venetum using quantitative real-time PCR (qRT-PCR), it is crucial to identify appropriate reference genes. This study selected nine candidate genes, including α-tubulin (TUA), β-tubulin (TUB), actin (ACT), cyclophilin (CYP), elongation factor-1α (EF-1α), the B family of regulatory subunits of protein phosphatase (PPP2R2, PPP2R3, and PPP2R5), and phosphoglycerate kinase (PGK), to determine the most appropriate reference genes in the leaf, stem, and root tissues of A. venetum. A comprehensive ranking by geNorm, NormFinder, BestKeeper, and RefFinder software and Venn diagrams was used to screen more stable reference genes in different tissues. The two most stable reference genes were CYP and TUA in leaves, PGK and PPP2R3 in stems, and TUA and EF-1α in roots, respectively. The relative expression values of the four genes involved in proline metabolism under polyethylene glycol treatment were used to validate the screened reference genes, and they exhibited highly stable expression levels. These findings represent the first set of stable reference genes for future gene expression studies in A. venetum. They significantly contribute to enhancing the accuracy and reliability of gene expression analyses in this economically important plant species.
11
Sun, Yong, Fanghua Guo, Xin Peng, Kejun Cheng, Lu Xiao, Hua Zhang, Hongyan Li, Li Jiang, and Zeyuan Deng. "Metabolism of Phenolics of Tetrastigma hemsleyanum Roots under In Vitro Digestion and Colonic Fermentation as Well as Their In Vivo Antioxidant Activity in Rats." Foods 10, no. 9 (September 8, 2021): 2123. http://dx.doi.org/10.3390/foods10092123.
Full textAbstract:
Tetrastigma hemsleyanum Diels et Gilg is a herbaceous perennial species distributed mainly in southern China. The Tetrastigma hemsleyanum root (THR) has been prevalently consumed as a functional tea or dietary supplement. In vitro digestion models, including colonic fermentation, were built to evaluate the release and stability of THR phenolics with the method of HPLC-QqQ-MS/MS and UPLC-Qtof-MS/MS. From the oral cavity, the contents of total phenolic and flavonoid began to degrade. Quercetin-3-rutinoside, quercetin-3-glucoside, kaempferol-3-rutinoside, and kaempferol-3-glucoside were metabolized as major components and they were absorbed in the form of glycosides for hepatic metabolism. On the other hand, the total antioxidant capacity (T-AOC), superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) activity, and glutathione (GSH) content were significantly increased, while malondialdehyde (MDA) content was decreased in plasma and tissues of rats treated with THR extract in the oxidative stress model. These results indicated that the THR extract is a good antioxidant substance and has good bioavailability, which can effectively prevent some chronic diseases caused by oxidative stress. It also provides a basis for the effectiveness of THR as a traditional functional food.
12
Mudau, Nixwell F., Puffy Soundy, and Elsa S. du Toit. "Plant Growth and Development of Bush Tea as Affected by Nitrogen, Phosphorus, and Potassium Nutrition." HortScience 40, no. 6 (October 2005): 1898–901. http://dx.doi.org/10.21273/hortsci.40.6.1898.
Full textAbstract:
Bush tea (Athrixia phylicoides) belongs to the Asteraceae family. It is a popular beverage used as an herbal tea and as medicine for cleansing or purifying the blood, treating boils, headaches, infested wounds, and cuts, and the solutions may also be used as a foam bath. In some parts of South Africa, people drink bush tea for aphrodisiac reasons. Bush tea was grown under varying N, P, and K levels in all four seasons to determine the seasonal nutrient requirements for improved plant growth. Three parallel trials for N, P, or K one at each season were laid out in a randomized complete block design (RCBD) with six treatments replicated eight times. Treatments consisted of 0, 100, 200, 300, 400, or 500 kg·ha–1 N, P, or K. Parameters recorded were plant height, number of branches and leaves, fresh and dry stem mass, fresh and dry root mass, stem girth, fresh and dry shoot mass, leaf area and percentage leaf and root tissue N, P, and K. Results of this study demonstrated that, in all trials regardless of season, N, P, or K nutrition increased bush tea fresh and dry shoot mass, plant height, number of leaves, number of branches and leaf area. Regardless of season, the optimum level of N, P and K fertilization for bush tea on growth parameters was 300 kg·ha-1 N or P and 200 kg·ha-1 for K. No significant differences in number of flowers and buds (fall and winter), stem girth, fresh and dry root mass as well as fresh and dry stem mass were obtained.
13
Hu, Bing, Amal Nadiri, Sabine Kuchler-Bopp, Fabienne Perrin-Schmitt, Heiko Peters, and Hervé Lesot. "Tissue Engineering of Tooth Crown, Root, and Periodontium." Tissue Engineering 12, no. 8 (August 2006): 2069–75. http://dx.doi.org/10.1089/ten.2006.12.2069.
Full text
14
Sidarningsih, Sidarningsih, Indeswati Diyatri, Reinaya Tifa Pratiwi, Jihan Hijriya Nabilla, Yuliati Yuliati, and Rini Devijanti Ridwan. "Epigallocatechin gallate Mucoadhesive Gingival Patch as Potential Biomaterial to Regulate Macrophage and Lymphocyte Cells in Periodontitis: A Review." Indonesian Journal of Dental Medicine 5, no. 1 (June 27, 2022): 32–36. http://dx.doi.org/10.20473/ijdm.v5i1.2022.32-36.
Full textAbstract:
Background: Periodontitis is a periodontal disease that affects more than 743 million peopleworldwide and causes damage to the periodontal ligament and alveolar bone. One of the bacteriathat can cause periodontitis is Porphyromonas gingivalis (P.gingivalis). P. gingivalis has virulence factors that can damage the periodontal tissue. Treatment of periodontitis is in the form of non- surgical therapy such as scaling and root planning and some cases, doxycycline can be given as adjunctive therapy after scaling and root planing. Epigallocatechin gallate (EGCG) is one of the catechins found in green tea and has anti-bacterial properties. Purpose: The study aimed to describe the potency of the mucoadhesive gingival patch with EGCG green tea against the number of macrophage cells and lymphocyte cells during periodontitis through narrative review. Review: Mucoadhesive gingiva patch loaded with EGCG has the advantages such as maintaining drug bioavailability, non-invasive, and optimizing drug distribution. Using a mucoadhesive gingiva patch with EGCG can reduce macrophage and lymphocyte cells by inhibiting lipopolysaccharide, a virulence factor of P. gingivalis. Inhibited lipopolysaccharide will inhibit pro-inflammatory cytokines such as TNF-α and IL-6. Macrophage and lymphocyte cells will reduce due to the inhibition of pro inflammatory cytokines. Conclusion: Mucoadhesive gingiva patch with EGCG green tea potentially to decreased macrophage and lymphocyte cells in periodontitis.
15
Eskundari, Ratna Dewi, Taryono Taryono, Didik Indradewa, and Yekti Asih Purwestri. "Morphological, Histological, and Protein Profiling of Tea Embryo Axis at Early Stage of Culture." Journal of Tropical Biodiversity and Biotechnology 6, no. 3 (October 18, 2021): 64403. http://dx.doi.org/10.22146/jtbb.64403.
Full textAbstract:
Tissue culture is an alternative choice of plant propagation either through somatic embryogenesis or in vitro organogenesis techniques. TRI2025 tea clone has been cultured successfully, however, the scientific information related to morphology, histology, and protein profile at an early event of culturing time has not been reported yet. This study aimed to determine the differences between those pathways, in the context of morphology, histology, and protein profile. The explants were the embryo axis of TRI2025 tea clone cultured on two different induction mediums; somatic embryogenesis and in vitro organogenesis induction medium. The results showed that most of the explants cultured on A medium developed to be a globular-like structure at 11-day after culture (DAC), while all explants cultured on B medium showed the initiation stage of in vitro organogenesis. Histological analysis showed meristem reconstruction at shoot apical meristem (SAM) and root apical meristem (RAM) at 11-DAC at explants cultured on B medium, while explants cultured on A medium showed callusing at 21-DAC. Protein profile analysis using SDS-PAGE showed protein bands of 54 and 81 KDa that only appeared at explants cultured on A medium start from 14-DAC, and those two protein bands thought to be a differentiator at the early stages of the two tissue culture techniques. Thus, these parameters can be used as early detection for plant tissue culture, especially in tea.
16
Nurniza, Nita, Ina Hendiani, and Ira Komara. "Pengaruh aplikasi gel teh hijau (Camellia sinensis) terhadap kadar total antioxidant capacity (TAOC) sebagai perawatan tambahan dari skeling dan root planing pada pasien dengan periodontitis kronisEffect of green tea (Camellia sinensis) gel application on the total antioxidant capacity (TAOC) levels as adjunct to scaling and root planing in patients with chronic periodontitis." Jurnal Kedokteran Gigi Universitas Padjadjaran 32, no. 2 (August 31, 2020): 156. http://dx.doi.org/10.24198/jkg.v32i2.27771.
Full textAbstract:
Pendahuluan: Mekanisme peradangan periodontitis kronis menghasilkan reaksi oksidasi, diketahui melalui kadar total antioxidant capacity (TAOC) cairan sulkus gingiva. Teh hijau dapat menghambat bakteri patogen periodontal sehingga kerusakan jaringan periodontal tidak bertambah parah. Tujuan penelitian adalah menganalisis kadar TAOC sebelum dan sesudah skeling dan root planing disertai gel teh hijau sebagai antioksidan. Metode: Jenis penelitian eksperimen semu, rumus ukuran sampel untuk menguji perbedaan dua rata-rata data tidak berpasangan, setiap subyek memiliki poket ≥ 5 mm, dikelompokkan sisi uji (n=14) dan sisi kontrol (n=14) (split mouth). Pengambilan cairan sulkus gingiva dilakukan pada hari ke-0, 15, dan 30, menggunakan metode absorbing paper strip dengan cara intracrevicular. Kedua sisi dilakukan skeling dan root planing, sisi uji diberikan gel. Hasil: Perbandingan kadar TAOC antara sisi kontrol dan sisi uji pada hari ke-0 (p=0,986), hari ke-15 (p=0,836), dan hari ke-30 (p=0,371) menunjukkan tidak terdapat perbedaan bermakna (p-value>0,05). Perbandingan rerata selisih kadar TAOC dalam kedua kelompok antara hari ke-0 dengan ke-15 (p=0,946), hari ke-0 dengan hari ke-30 (p=0,504), serta hari ke-15 dengan hari ke-30 (p=0,811) jugwa menunjukkan tidak terdapat perbedaan bermakna. Simpulan: Tidak terdapat pengaruh aplikasi gel teh hijau (Camellia sinensis) terhadap kadar total antioxidant capacity (TAOC) pada perawatan periodontitis kronis berupa skeling dan root planing.Kata kunci: Gel teh hijau, periodontitis kronis, skeling dan root planing, total antioxidant capacity (TAOC). ABSTRACTIntroduction: The inflammatory mechanism of chronic periodontitis produces an oxidation reaction, measured through the level of total antioxidant capacity (TAOC) of the gingival crevicular fluid. Green tea can inhibit periodontal pathogenic bacteria so that periodontal tissue damage will not worsen. This study was aimed to analyse the levels of TAOC before and after scaling and root planing with green tea gel as an antioxidant. Methods: The research was quasi-experimental. The sample size formula was used to test the difference between two unpaired data means. Each subject has a pocket ≥ 5 mm, grouped by the test side (n = 14) and the control side (n = 14) (split-mouth). The gingival crevicular fluid was collected on days 0, 15, and 30, using the intracrevicular method with absorbing paper strips. Both sides were treated with scaling and root planing, and the test side was administered with the green tea gel. Results: Comparison of TAOC levels between the control side and the test side on day 0 (p = 0.986), day 15 (p = 0.836), and day 30 (p = 0.371) showed no significant difference (p-value > 0.05). Comparison of the mean difference of the TAOC levels in two groups between day 0 with day 15 was p = 0.946, day 0 with day 30 was p = 0.504, and day 15 with day 30 was p = 0.811; which also showed no significant difference. Conclusion: There is no effect of green tea gel (Camellia sinensis) application on the Total Antioxidant Capacity (TAOC) level in chronic periodontitis treatment in the form of scaling and root planing.Keywords: Green tea gel, chronic periodontitis, scaling and root planing, total antioxidant capacity (TAOC).
17
Shan, Wenna, Ying Zhou, Huihui Liu, and Xiaomin Yu. "Endophytic Actinomycetes from Tea Plants (Camellia sinensis): Isolation, Abundance, Antimicrobial, and Plant-Growth-Promoting Activities." BioMed Research International 2018 (November 1, 2018): 1–12. http://dx.doi.org/10.1155/2018/1470305.
Full textAbstract:
Endophytic actinomycetes are a promising source of novel metabolites with diverse biological activities. Tea plants (Camellia sinensis) produce arsenals of phytochemicals, which are linked to a number of medicinal and nutritional properties. However, a systematic investigation into the abundance and diversity of cultivated actinomycetes residing in tea plants has not been performed. In this study, a total of 46 actinobacteria were recovered from leaf, stem, and root samples of 15 tea cultivars collected in Fujian province, China. Their abundance and diversity were shown to be influenced by both the genotypes and tissue types of tea plants. Based on 16S RNA sequence analysis, these isolates were taxonomically grouped into 11 families and 13 genera, includingStreptomyces,Actinomadura,Kribbella,Nocardia,Kytococcus,Leifsonia,Microbacterium,Micromonospora,Mobilicoccus,Mycobacterium,Nocardiopsis,Piscicoccus, andPseudonocardia. The genusStreptomyceswas most prevalent whereas rare genera,MobilicoccusandPiscicoccus, were reported for the first time to occur as plant endophytes. PCR screening of polyketide synthase genes (PKS-I and PKS-II) and nonribosomal peptide synthetase genes (NRPS), along with antimicrobial assays against a set of bacterial and fungal pathogens, showed that endophytic actinomycetes associated with tea plants have a high potential for producing antimicrobial metabolites. Furthermore, indole acetic acid (IAA) production and 1-aminocyclopropane-1-carboxylic acid (ACC) deaminase activities were recorded in 93.5% and 21.7% of all isolates, respectively. Overall, these results indicate that endophytic actinomycetes from tea plants represent a valuable source of bioactive metabolites with antibacterial, antifungal, and plant-growth-promoting properties.
18
Vajrabhaya, La-ongthong, Vanida Sangalungkarn, Ratchapin Srisatjaluk, Suwanna Korsuwannawong, and Chareerut Phruksaniyom. "Hypochlorite solution for root canal irrigation that lacks a chlorinated odor." European Journal of Dentistry 11, no. 02 (April 2017): 221–25. http://dx.doi.org/10.4103/ejd.ejd_354_16.
Full textAbstract:
ABSTRACT Objectives: This is an in vitro study to develop a formulation of a hypochlorite solution for root canal irrigation that lacks a chlorinated odor. The antibacterial effect, tissue dissolution efficacy, and the cytotoxicity of the solution were assessed in cell culture and were compared with those of commercial sodium hypochlorite (NaOCl) solutions. Materials and Methods: Trichloroisocyanuric acid (TCA) was used as the source of hypochlorite ions in solution. All required properties of the NaOCl irrigant were evaluated and compared with those of original 2.5% NaOCl solutions currently in use. Results: Our results revealed that a TCA 3.5% + 1/6 Buffer-1 solution passed the short-term stability test. Moreover, no odor of chlorine gas was detected by three independent observers. The hypochlorite ion content and pH were stable over an incubation period of 4 weeks. The new solution did not differ from commercial products in terms of the dissolution property on bovine pulpal tissue (P > 0.05). Moreover, the antibacterial effect of this solution on Enterococcus faecalis did not differ from that of the commercial products (P > 0.05). In addition, our biocompatibility analysis demonstrated no difference among the tested solutions (P > 0.05). Conclusions: According to the results of all properties tested, TCA 3.5% + 1/6 Buffer-1 could be considered an option for NaOCl irrigation with the benefit of no detectable chlorine odor.
19
Drew, RA, and JN Vogler. "Field evaluation of tissue-cultured papaw clones in Queensland." Australian Journal of Experimental Agriculture 33, no. 4 (1993): 475. http://dx.doi.org/10.1071/ea9930475.
Full textAbstract:
Field performance of tissue-cultured clones of papaws established either from adult tissue of a high-yielding female plant or from juvenile tissue of seedlings (2 females and 2 hermaphrodites) was compared with seedling controls. All tissue-cultured plants had strong root systems and established more quickly than seedlings. Plants from adult tissue (TCA) had a reduced juvenile phase, as evidenced by increased circumference, lower height of first flower, reduced time to harvest, and higher fruit numbers per metre of stem. Planting date affected node number of first flower for TCA plants but not seedlings. TCA plants had higher yields than seedlings when planted in spring, and this could lead to improved commercial practice. Differences between clones established from juvenile tissue and their respective seedling controls varied and were not consistent with a reduced juvenile phase. Four dwarf off-type plants (<1% of population) originated from a single bud explant.
20
Gerlyand, Alexander M., and Daniel S. Sitar. "Protein kinase inhibition differentially regulates organic cation transportThis article is one of a selection of papers published in a special issue celebrating the 125th anniversary of the Faculty of Medicine at the University of Manitoba." Canadian Journal of Physiology and Pharmacology 87, no. 10 (October 2009): 821–30. http://dx.doi.org/10.1139/y09-072.
Full textAbstract:
Previous studies showed that amantadine transport increased while tetraethylammonium (TEA) transport decreased in kidney tissue from diabetic rats. Changes in transport activity were reversed by exogenous insulin. We hypothesized that this difference in transport regulation is due to differential regulation of different transport systems. Native human embryonic kidney cortex cells (HEK293 cell line) and rat organic cation transporter (rOCT)-transfected cells were used to test the hypothesis. In support of differential regulation, short-term glucose starvation stimulated amantadine transport and inhibited TEA transport, but the effect was bicarbonate-modulated only for amantadine. cAMP analogues inhibited TEA transport while stimulating amantadine transport. This effect was additive to the effect of insulin, and the presence of bicarbonate affected the extent of the change. Our findings indicated that regulation of rOCT 1 and 2 was mediated by transmembrane adenylyl cyclase, and regulation of amantadine transport was mediated by soluble adenylyl cyclase, suggesting that intracellular microdomains of cAMP may be important in determining overall cellular transport for organic cations. Soluble adenylyl cyclase activity is known to be modulated by bicarbonate and lactate. These observations support our hypothesis and reconcile our previous studies demonstrating increased transport affinity for amantadine in the presence of bicarbonate and decreased transport affinity in the presence of lactate.
21
Kumar, G. N. M., and N. R. Knowles. "INCREASED PEROXIDATIVE DAMAGE AND DECREASED PROTEIN SYNTHESIS ARE FEATURES OF AGING POTATO SEED-TUBERS." HortScience 27, no. 6 (June 1992): 623g—624. http://dx.doi.org/10.21273/hortsci.27.6.623g.
Full textAbstract:
The physiological mechanisms leading to a decline in sprout-vigor, root growth potential and apical dominance during long-term aging of potato seed tubers are currently under investigation. Malondialdehyde (MDA) and ethane, products of peroxidative degradation of PUFA increase in seed-tuber tissues with advancing age (from 2 to 32 months of storage). MDA is known to react with free amino acids to produce lipofuscin-like fluorescent compounds (FC), which build-up in aging/senescent tissues of plants and animals. With advancing seed-tuber age, an increase in free amino acids, MDA and FC concentrations was evident. Moreover, high levels of MDA have been shown to reduce protein synthesis in both plant and animal cells. We therefore examined the extent to which seed-tuber age affects protein synthesizing capacity of tuber tissues during sprouting. Tissue disks from 6- and 18-mo-old seed-tubers at various stages of sprouting, were compared for their protein synthesizing ability by monitoring the incorporation of radiolabelled amino acids into TCA precipitable products. The rate of incorporation (dpm mg protein-1 min-1) was 1.8 to 5.4-fold higher in tissue from 6-mo-old, as compared to that from 18-mo-old seed tubers, at similar stages of sprout development. Loss in protein synthesizing ability (possibly due to direct peroxidative damage) may be an important factor contributing to loss of sprout-vigor from aged potato seed-tubers.
22
Grabelnych, O. I., E. A. Polykova, A. V. Korsukova, N. S. Zabanova, E. V. Berezhnaya, I. V. Lyubushkina, O. A. Fedotova, A. V. Stepanov, T. P. Pobezhimova, and N. V. Dorofeev. "Differently Directional Effects of Tebuconazole-Based Disinfectant of Seeds “Bunker” on the Growth of Winter Wheat Shoots and Roots." Bulletin of Irkutsk State University. Series Biology. Ecology 34 (2020): 3–19. http://dx.doi.org/10.26516/2073-3372.2020.34.3.
Full textAbstract:
Derivatives of a triazole are used not only as fungicides to prevent infection of plants, but also for treatment. These drugs are actively used against plant diseases caused by basidiomycetes, ascomycetes, and some deuteromycetes. Due to their chemical stability, they have a long-term protective effect, and their solubility in water ensures their movement from the roots to the aerial part of plants. The aim of this work was to study the effect of seed treatment with tebuconazole-containing preparation “Bunker” on the growth of shoots and roots of winter wheat in the light and physiological and biochemical parameters. We used a fungicide of prophylactic and therapeutic action tebuconazole-containing seed treater “Bunker” (August, Russia), the active ingredient of which is tebuconazole (60 g/L). The shoot length and total root length, wet and dry biomass, as well as the content of photosynthetic pigments, reactive oxygen species – hydrogen peroxide (H2O2) and lipid peroxidation products (LPO) reacting with thiobarbituric acid (TBA-RP) in the tissues of shoots and roots were analyzed. The content of chlorophylls a and b and carotenoids in the extract was determined spectrophotometrically at wavelengths of 665, 649, and 440 nm, respectively. The obtained results indicate that the action of the drug is aimed at inhibiting the growth of shoots and reducing the ratio of shoot length to root length, while on the 7-9th day of growth, the effectiveness of its action is higher, and the most significant effect is exerted by an increased dose of the disinfectant (1.5 μL/g). It was found statistically significant stimulation of root growth on the 9th day of cultivation, regardless of the dose of the dressing agent. Despite the significant growth-inhibiting effect, treatment with Bunker was not accompanied by activation of oxidative processes in shoot tissues, with the exception of an increase in the content of H2O2 and TBA-RP at the initial stage of growth (5 days). In root tissues, the content of H2O2 and TBA did not change under the action of the studied preparation. No differences in the content of chlorophylls a and b and carotenoids in the tissues of wheat shoots after treatment with the studied fungicide were found. Based on the data obtained, it can be concluded that seed dressing agents containing tebuconazole as an active ingredient can be used to ensure plant resistance to moisture deficiency and improve mineral nutrition.
23
Van Nguyen, Truong, So-Wun Kim, Cheol-Woo Min, Ravi Gupta, Gi-Hyun Lee, Jeong-Woo Jang, Divya Rathi, et al. "Optimization of Protein Isolation and Label-Free Quantitative Proteomic Analysis in Four Different Tissues of Korean Ginseng." Plants 10, no. 7 (July 9, 2021): 1409. http://dx.doi.org/10.3390/plants10071409.
Full textAbstract:
Korean ginseng is one of the most valuable medicinal plants worldwide. However, our understanding of ginseng proteomics is largely limited due to difficulties in the extraction and resolution of ginseng proteins because of the presence of natural contaminants such as polysaccharides, phenols, and glycosides. Here, we compared four different protein extraction methods, namely, TCA/acetone, TCA/acetone–MeOH/chloroform, phenol–TCA/acetone, and phenol–MeOH/chloroform methods. The TCA/acetone–MeOH/chloroform method displayed the highest extraction efficiency, and thus it was used for the comparative proteome profiling of leaf, root, shoot, and fruit by a label-free quantitative proteomics approach. This approach led to the identification of 2604 significantly modulated proteins among four tissues. We could pinpoint differential pathways and proteins associated with ginsenoside biosynthesis, including the methylerythritol 4–phosphate (MEP) pathway, the mevalonate (MVA) pathway, UDP-glycosyltransferases (UGTs), and oxidoreductases (CYP450s). The current study reports an efficient and reproducible method for the isolation of proteins from a wide range of ginseng tissues and provides a detailed organ-based proteome map and a more comprehensive view of enzymatic alterations in ginsenoside biosynthesis.
24
Liu, Mengmeng, and Janusz J. Zwiazek. "Transcriptomic Analysis of Distal Parts of Roots Reveals Potentially Important Mechanisms Contributing to Limited Flooding Tolerance of Canola (Brassica napus) Plants." International Journal of Molecular Sciences 23, no. 24 (December 7, 2022): 15469. http://dx.doi.org/10.3390/ijms232415469.
Full textAbstract:
Since most of the root metabolic activities as well as root elongation and the uptake of water and mineral nutrients take place in the distal parts of roots, we aimed to gain insight into the physiological and transcriptional changes induced by root hypoxia in the distal parts of roots in canola (Brassica napus) plants, which are relatively sensitive to flooding conditions. Plants were subject to three days of root hypoxia via lowering oxygen content in hydroponic medium, and various physiological and anatomical features were examined to characterize plant responses. Untargeted transcriptomic profiling approaches were also applied to investigate changes in gene expression that took place in the distal root tissues in response to hypoxia. Plants responded to three days of root hypoxia by reducing growth and gas exchange rates. These changes were accompanied by decreases in leaf water potential (Ψleaf) and root hydraulic conductivity (Lpr). Increased deposition of lignin and suberin was also observed in the root tissues of hypoxic plants. The transcriptomic data demonstrated that the effect of hypoxia on plant water relations involved downregulation of most BnPIPs in the root tissues with the exception of BnPIP1;3 and BnPIP2;7, which were upregulated. Since some members of the PIP1 subfamily of aquaporins are known to transport oxygen, the increase in BnPIP1;3 may represent an important hypoxia tolerance strategy in plants. The results also demonstrated substantial rearrangements of different signaling pathways and transcription factors (TFs), which resulted in alterations of genes involved in the regulation of Lpr, TCA (tricarboxylic acid) cycle-related enzymes, antioxidant enzymes, and cell wall modifications. An integration of these data enabled us to draft a comprehensive model of the molecular pathways involved in the responses of distal parts of roots in B. napus. The model highlights systematic transcriptomic reprogramming aimed at explaining the relative sensitivity of Brassica napus to root hypoxia.
25
Ramadhani, Yeka, Riski Rahayu Putri Rahmasari, Kinanti Nasywa Prajnasari, Moh Malik Alhakim, Mohammed Aljunaid, Hesham Mohammed Al-Sharani, T. Tantiana, Wisnu Setyari Juliastuti, Rini Devijanti Ridwan, and Indeswati Diyatri. "A mucoadhesive gingival patch with Epigallocatechin-3-gallate green tea (Camellia sinensis) as an alternative adjunct therapy for periodontal disease: A narrative review." Dental Journal (Majalah Kedokteran Gigi) 55, no. 2 (June 1, 2022): 114–19. http://dx.doi.org/10.20473/j.djmkg.v55.i2.p114-119.
Full textAbstract:
Background: Periodontitis is a progressive destructive periodontal disease. The prevalence of periodontal disease in Indonesia reaches 74.1% and mostly occurs in the productive age group. Most of the periodontopathogenic bacteria are gram-negative bacteria and have endotoxin in the form of lipopolysaccharide (LPS), which can penetrate the periodontal tissue and induce an inflammatory response. In inflammatory conditions, osteoclastic activity is higher than osteoblastic activity, which causes bone destruction. This results in an imbalance between osteoclast-induced bone resorption and osteoblast-induced bone formation. The current preferred treatment for periodontitis is scaling root planning (SRP), but this therapy cannot repair the damaged periodontal tissue caused by periodontitis. Purpose: To describe the possibility of using a mucoadhesive gingival patch with Epigallocatechin-3-gallate (EGCG) green tea (Camellia sinensis) as alternative adjunct therapy for periodontal disease. Review: EGCG is the main component of green tea catechins, which have antitumor, antioxidant, anti-inflammatory, anti-fibrotic, and pro-osteogenic effects. However, the weaknesses so far regarding the use of EGCG as an alternative treatment is its low oral bioavailability and the concentration of EGCG absorbed by the body decreasing when accompanied by food. EGCG can be used with a mucoadhesive gingival patch to optimise bioavailability and absorption and increase local concentration and sustained release of EGCG. EGCG encourages bone development and braces mesenchymal stem cells (MSCs) differentiation for osteoblast by enhancing the expression of bone morphogenic protein 2 (BMP2). EGCG also has been proven to increase the expression of RUNX2 and ALP activity that induces osteoblast differentiation and bone mineralisation. Conclusion: A mucoadhesive gingival patch containing EGCG Green Tea (C. sinensis) may potentially induce osteoblastic activity as an adjunct therapy to repair the periodontal tissue damage due to periodontal disease.
26
Aktar, Shirin, Peixian Bai, Liubin Wang, Hanshuo Xun, Rui Zhang, Liyun Wu, Mengdi He, Hao Cheng, Liyuan Wang, and Kang Wei. "Identification of a BAHD Acyltransferase Gene Involved in Plant Growth and Secondary Metabolism in Tea Plants." Plants 11, no. 19 (September 22, 2022): 2483. http://dx.doi.org/10.3390/plants11192483.
Full textAbstract:
Plant acyl-CoA dominated acyltransferases (named BAHD) comprise a large appointed protein superfamily and play varied roles in plant secondary metabolism like synthesis of modified anthocyanins, flavonoids, volatile esters, etc. Tea (Camellia sinensis) is an important non-alcoholic medicinal and fragrancy plant synthesizing different secondary metabolites, including flavonoids. In the tea (C.A sinensis) cultivar Longjing 43 (LJ43), eight samples were performed into three groups for transcriptome analysis under three biological replications. Among the BAHD acyltransferase genes in tea cultivars, the expression of TEA031065 was highest in buds and young leaves following the RNA sequencing data, which was coincident with the tissue rich in catechins and other flavonoids. We then transformed this gene into wild-type Arabidopsis as an over-expression (OX) line 1 and line 2 in ½ MS media to verify its function. In the wild types (WT), the primary root length, number of secondary roots, and total root weight were significantly higher at 24%, 15%, and 53.92%, respectively, compared to the transgenic lines (OX1 and OX2). By contrast, the leaves displayed larger rosettes (21.58%), with higher total leaf weight (32.64%) in the transgenic lines than in the wild type (WT). This result is consistent with DCR mutant At5g23940 gene in Arabidopsis thaliana. Here, anthocyanin content in transgenic lines was also increased (21.65%) as compared to WT. According to the RNA sequencing data, a total of 22 growth regulatory genes and 31 structural genes with TFs (transcription factors) that are correlative with plant growth and anthocyanin accumulation were identified to be differentially expressed in the transgenic lines. It was found that some key genes involved in IAA (Auxin) and GA (Gibberellin) biosynthesis were downregulated in the transgenic lines, which might be correlated with the phenotype changes in roots. Moreover, the upregulation of plant growth regulation genes, such as UGT73C4 (zeatin), ARR15, GH3.5, ETR2, ERS2, APH4, and SAG113 might be responsible for massive leaf growth. In addition, transgenic lines shown high anthocyanin accumulation due to the upregulation of the (1) 3AT1 and (3) GSTF, particularly, GSTF12 genes in the flavonoid biosynthesis pathway. However, the TFs such as, CCoAMT, bHLH, WRKY, CYP, and other MYBs were also significantly upregulated in transgenic lines, which increased the content of anthocyanins in A. thaliana seedlings. In conclusion, a BAHD acyltransferase (TEA031065) was identified, which might play a vital role in tea growth and secondary metabolites regulation. This study increases our knowledge concerning the combined functionality of the tea BAHD acyltransferase gene (TEA031065).
27
Rotimi, Damilare Emmanuel, Goodnews Mavoghenegbero Ben-Goru, Ikponmwosa Owen Evbuomwan, Tobiloba Christiana Elebiyo, Mohammed Alorabi, Abdullah Farasani, Gaber El-Saber Batiha, and Oluyomi Stephen Adeyemi. "Zingiber officinale and Vernonia amygdalina Infusions Improve Redox Status in Rat Brain." Evidence-Based Complementary and Alternative Medicine 2022 (September 26, 2022): 1–9. http://dx.doi.org/10.1155/2022/9470178.
Full textAbstract:
The study investigated the effects of Zingiber officinale root and Vernonia amygdalina leaf on the brain redox status of Wistar rats. Twenty-four (24) rats weighing 160 ± 20 g were randomly assigned into four (4) groups, each with six (6) rats. Animals in Group 1 (control) were orally administered distilled water (1 mL), while the test groups were orally administered 5 mg/mL of either Z. officinale, V. amygdalina infusion, or a combination of both, respectively, for 7 days. The rats were sacrificed at the end of treatments and blood and tissue were harvested and prepared for biochemical assays. Results showed that administration of V. amygdalina and Z. officinale, as well as their coadministration, reduced the levels of malondialdehyde (MDA), nitric oxide (NO), acetylcholinesterase (AChE), and myeloperoxidase (MPO) in rat brain tissue compared with the control group. Conversely, coadministration of V. amygdalina and Z. officinale increased the levels of reduced glutathione (GSH) in rat brain tissue compared with the control group. However, the administration of the infusions singly, as well as the combination of both infusions, did not have any effect on the rat brain levels of glutathione peroxidase (GPx) and catalase (CAT) antioxidant enzymes compared to the control. Taken together, the findings indicate that the V. amygdalina and Z. officinale tea infusions have favorable antioxidant properties in the rat brain. The findings are confirmatory and contribute to deepening our understanding of the health-promoting effects of V. amygdalina and Z. officinale tea infusions.
28
Vavilova, L. V., and B. V. Korzun. "Studying the adaptability of promising breeding forms of tea to static environmental factors." New Technologies 18, no. 4 (February 24, 2023): 139–49. http://dx.doi.org/10.47370/2072-0920-2022-18-4-139-149.
Full textAbstract:
The article presents the results of a long-term assessment of the adaptive potential of breeding forms of tea plants cultivated in the natural and climatic conditions of the North-Western Caucasus (the Republic of Adygea) in order to select the most promising samples from the existing gene pool and use them to breed local highly adaptive varieties. In the course of studying adaptability, generally accepted methods have been used, including the «Program and Methodology for the Study of Fruit, Berry and Nut Crops», 1999 and «Determining the Resistance of Fruit and Berry Crops to Cold Season Stressors in Field and Controlled Conditions», 2002. Meteorological and climatic features of the tea growing area have been analyzed, weather conditions compared with the biorhythms of introduced plants, their influence on the state and productivity of tea noted. Correlation relationships between the temperature factor and the onset of the development phase of tea plants have been characterized. As a result, data have been obtained on the winter hardiness of the studied forms for various components, resistance to excess and lack of heat, and the characteristics of the growth and development of tea plants in various weather conditions and against the background of various regeneration processes have been analyzed. To accelerate the determination of the viability of the conducting system, the authors carried out the growth of damaged shoots at room temperature and presented in the article the results of observations that made it possible to see hidden local tissue damage and characterize their types. The most adaptive forms are AF-3 and AF-5, which show the best resistance to damaging environmental factors, have a high regenerative capacity and can provide a good harvest of green tea leaves for the sustainable development of tea growing in Adygea.
29
Chen, Shengxiang, Xujiao Wei, Xiaoli Hu, Peng Zhang, Kailin Chang, Dongyang Zhang, Wei Chen, et al. "Genome-Wide Analysis of Nuclear factor-YC Genes in the Tea Plant (Camellia sinensis) and Functional Identification of CsNF-YC6." International Journal of Molecular Sciences 25, no. 2 (January 9, 2024): 836. http://dx.doi.org/10.3390/ijms25020836.
Full textAbstract:
Nuclear factor Y (NF-Y) is a class of transcription factors consisting of NF-YA, NF-YB and NF-YC subunits, which are widely distributed in eukaryotes. The NF-YC subunit regulates plant growth and development and plays an important role in the response to stresses. However, there are few reports on this gene subfamily in tea plants. In this study, nine CsNF-YC genes were identified in the genome of ‘Longjing 43’. Their phylogeny, gene structure, promoter cis-acting elements, motifs and chromosomal localization of these gene were analyzed. Tissue expression characterization revealed that most of the CsNF-YCs were expressed at low levels in the terminal buds and at relatively high levels in the flowers and roots. CsNF-YC genes responded significantly to gibberellic acid (GA) and abscisic acid (ABA) treatments. We further focused on CsNF-YC6 because it may be involved in the growth and development of tea plants and the regulation of response to abiotic stresses. The CsNF-YC6 protein is localized in the nucleus. Arabidopsis that overexpressed CsNF-YC6 (CsNF-YC6-OE) showed increased seed germination and increased root length under ABA and GA treatments. In addition, the number of cauline leaves, stem lengths and silique numbers were significantly higher in overexpressing Arabidopsis lines than wild type under long-day growth conditions, and CsNF-YC6 promoted primary root growth and increased flowering in Arabidopsis. qPCR analysis showed that in CsNF-YC6-OE lines, flowering pathway-related genes were transcribed at higher levels than wild type. The investigation of the CsNF-YC gene has unveiled that CsNF-YC6 plays a pivotal role in plant growth, root and flower development, as well as responses to abiotic stress.
30
Viana, Luciana da Silva, Paulo Pedro da Silva, Velber Xavier Nascimento, Alessandro Riffel, and Antônio Euzébio Goulart Sant’Ana. "Comparison of methods for the extraction of proteins from root and leaf tissue of sugarcane (Saccharum spp.) for proteomic analysis." AUGUST 2020, no. 14(08):2020 (August 20, 2020): 1221–29. http://dx.doi.org/10.21475/ajcs.20.14.08.p2184.
Full textAbstract:
The extraction of proteins from plants is a crucial procedure for successful protein determination such as purification, separation, and mass spectrometry. Protein extraction from plant tissues is generally difficult due to the presence of various molecules (cell wall, polysaccharides, and lipids) and interfering compounds. For this reason, the step of separation of proteins is a big challenge in obtaining good results in plant proteomic studies, notably from sugarcane. The current study assesses three extraction methods to prepare protein samples for proteomic analysis. Method 1 (control): TCA/acetone, method 2: TCA/acetone modified and Method 3: Phenol/SDS/ammonium acetate. Plants of cultivar RB92579 were grown in 10L pots under ideal humidity conditions in a greenhouse for 60 days. Samples collected on leaves +1 and roots were carried out using nitrogen and stored in an ultra-freezer at -80ºC for later use in proteome assays. For the tested methods, a comparison was made between the quantitative and qualitative data obtained from the tissue of sugarcane leaves and roots. According to the results obtained, methods 2 and 3 produced the best yield in the extraction of total proteins from the leaves and roots of sugarcane, when compared to (control) method 1 (TCA/acetone). This can be observed when comparing the quantitative and qualitative data obtained using the different extraction methods. By comparing methods 2 and 3, the latter showed a massive gain of extracted proteins much greater than the first method, mainly when the extraction of total proteins from the roots are compared. Similarly, the 2-DE gels run after using method 3 showed less background, compared to method 2. Another observation was the presence of different “spots” in the 2-DE gels between the samples extracted using methods 2 and 3. Method 3 (phenol / SDS / ammonium acetate) presented better results for extraction of proteins and in the 2-DE gels, with a greater number of total and specific “spots”, greater reproducibility and less background. This method could be utilized as the standard method for proteomic studies in sugarcane.
31
NAKAMURA, Yoriyuki. "Effects of Origin of Explants on Differentiation of Root and Its Varietal Difference in Tissue Culture of Tea Plant." Chagyo Kenkyu Hokoku (Tea Research Journal), no. 62 (1985): 1–7. http://dx.doi.org/10.5979/cha.1985.62_1.
Full text
32
Hinder, Lucy M., Anuradha Vivekanandan-Giri, Lisa L. McLean, Subramaniam Pennathur, and Eva L. Feldman. "Decreased glycolytic and tricarboxylic acid cycle intermediates coincide with peripheral nervous system oxidative stress in a murine model of type 2 diabetes." Journal of Endocrinology 216, no. 1 (October 19, 2012): 1–11. http://dx.doi.org/10.1530/joe-12-0356.
Full textAbstract:
Diabetic neuropathy (DN) is the most common complication of diabetes and is characterized by distal-to-proximal loss of peripheral nerve axons. The idea of tissue-specific pathological alterations in energy metabolism in diabetic complications-prone tissues is emerging. Altered nerve metabolism in type 1 diabetes models is observed; however, therapeutic strategies based on these models offer limited efficacy to type 2 diabetic patients with DN. Therefore, understanding how peripheral nerves metabolically adapt to the unique type 2 diabetic environment is critical to develop disease-modifying treatments. In the current study, we utilized targeted liquid chromatography–tandem mass spectrometry (LC/MS/MS) to characterize the glycolytic and tricarboxylic acid (TCA) cycle metabolomes in sural nerve, sciatic nerve, and dorsal root ganglia (DRG) from male type 2 diabetic mice (BKS.Cg-m+/+Leprdb;db/db) and controls (db/+). We report depletion of glycolytic intermediates in diabetic sural nerve and sciatic nerve (glucose-6-phosphate, fructose-6-phosphate, fructose-1,6-bisphosphate (sural nerve only), 3-phosphoglycerate, 2-phosphoglycerate, phosphoenolpyruvate, and lactate), with no significant changes in DRG. Citrate and isocitrate TCA cycle intermediates were decreased in sural nerve, sciatic nerve, and DRG from diabetic mice. Utilizing LC/electrospray ionization/MS/MS and HPLC methods, we also observed increased protein and lipid oxidation (nitrotyrosine; hydroxyoctadecadienoic acids) indb/dbtissue, with a proximal-to-distal increase in oxidative stress, with associated decreased aconitase enzyme activity. We propose a preliminary model, whereby the greater change in metabolomic profile, increase in oxidative stress, and decrease in TCA cycle enzyme activity may cause distal peripheral nerves to rely on truncated TCA cycle metabolism in the type 2 diabetes environment.
33
Mudau, Fhatuwani N., Puffy Soundy, and Elsa S. du Toit. "Nitrogen, Phosphorus, and Potassium Nutrition Increases Growth and Total Polyphenol Concentrations of Bush Tea in a Shaded Nursery Environment." HortTechnology 17, no. 1 (January 2007): 107–10. http://dx.doi.org/10.21273/horttech.17.1.107.
Full textAbstract:
The objective of this investigation was to determine the effects of simultaneous applications of nitrogen (N), phosphorus (P), and potassium (K) nutrition on growth and chemical analysis of bush tea (Athrixia phylicoides). Four consecutive trials were conducted at Morgenzon (Louis Trichardt, Limpopo Province, South Africa), a commercial nursery, one at each season (autumn, winter, spring, and summer) under 50% shade. Treatments comprised three levels of N (300, 350, 400 kg·ha−1), three levels of P (250, 300, 350 kg·ha−1), and three levels K (150, 200, 250 kg·ha−1). The experimental design was a 3 × 3 × 3 factorial experiment arranged in a randomized complete-block design with four replications. Parameters recorded were plant height, number of branches and leaves, fresh and dry stem weight, fresh and dry root weight, stem girth, fresh and dry shoot weight, leaf area, and percent concentration of leaf and root tissue N, P, K, and total polyphenol concentrations as influenced by season in a shaded nursery environment. Treatment combinations of N and P at rates of 300 kg·ha−1 and K at 200 kg·ha−1 increased fresh and dry shoot weight, number of leaves, leaf area, and concentration of total polyphenols. Other treatments did not consistently affect concentrations of leaf N, P, or K during the study period, although the treatment that received combinations of N and P at rates of 300 kg·ha−1 and K at 200 kg·ha−1 always had the highest concentrations of leaf N, P, and K and lowest root N, P, and K concentrations. No differences in plant height, number of branches, number of flower buds (autumn and winter), stem girth, fresh and dry root weight, and fresh and dry stem weight due to treatment combinations were observed.
34
Hinton, Robert B. "Bicuspid Aortic Valve and Thoracic Aortic Aneurysm: Three Patient Populations, Two Disease Phenotypes, and One Shared Genotype." Cardiology Research and Practice 2012 (2012): 1–11. http://dx.doi.org/10.1155/2012/926975.
Full textAbstract:
Bicuspid aortic valve (BAV) and thoracic aortic aneurysm (TAA) are two discrete cardiovascular phenotypes characterized by latent progressive disease states. There is a clear association between BAV and TAA; however the nature and extent of this relationship is unclear. There are both distinct and overlapping developmental pathways that have been established to contribute to the formation of the aortic valve and the aortic root, and the mature anatomy of these different tissue types is intimately intertwined. Likewise, human genetics studies have established apparently separate and common contributions to these clinical phenotypes, suggesting complex inheritance and a shared genetic basis and translating 3 patient populations, namely, BAV, TAA, or both, into a common but diverse etiology. A better understanding of the BAV-TAA association will provide an opportunity to leverage molecular information to modify clinical care through more sophisticated diagnostic testing, improved counseling, and ultimately new pharmacologic therapies.
35
Shariatipour, Nikwan, and Bahram Heidari. "Investigation of Drought and Salinity Tolerance Related Genes and their Regulatory Mechanisms in Arabidopsis (Arabidopsis thaliana)." Open Bioinformatics Journal 11, no. 1 (March 7, 2018): 12–28. http://dx.doi.org/10.2174/1875036201811010012.
Full textAbstract:
Background:The development of genome microarrays of the model plant;Arabidopsis thaliana, with increasing repositories of publicly available data and high-throughput data analysis tools, has opened new avenues to genome-wide systemic analysis of plant responses to environmental stresses.Objective:To identify differentially expressed genes and their regulatory networks inArabidopsis thalianaunder harsh environmental condition.Methods:Two replications of eight microarray data sets were derived from two different tissues (root and shoot) and two different time courses (control and 24 hours after the beginning of stress occurrence) for comparative data analysis through various bioinformatics tools.Results:Under drought stress, 2558 gene accessions in root and 3691 in shoot tissues had significantly differential expression with respect to control condition. Likewise, under salinity stress 9078 gene accessions in root and 5785 in shoot tissues were discriminated between stressed and non-stressed conditions. Furthermore, the transcription regulatory activity of differentially expressed genes was mainly due to hormone, light, circadian and stress responsivecis-acting regulatory elements among which ABRE, ERE, P-box, TATC-box, CGTCA-motif, GARE-motif, TGACG-motif, GAG-motif, GA-motif, GATA- motif, TCT-motif, GT1-motif, Box 4, G-Box, I-box, LAMP-element, Sp1, MBS, TC-rich repeats, TCA-element and HSE were the most important elements in the identified up-regulated genes.Conclusion:The results of the high-throughput comparative analyses in this study provide more options for plant breeders and give an insight into genes andcis-acting regulatory elements involved in plant response to drought and salinity stresses in strategic crops such as cereals.
36
Martini, Aikaterini N., Maria Papafotiou, Ioannis Massas, and Nikoleta Chorianopoulou. "Growing of the Cretan Therapeutic Herb Origanum Dictamnus in The Urban Fabric: The Effect of Substrate and Cultivation Site on Plant Growth and Potential Toxic Element Accumulation." Plants 12, no. 2 (January 11, 2023): 336. http://dx.doi.org/10.3390/plants12020336.
Full textAbstract:
Origanum dictamnus L. (Lamiaceae) is a perennial herb endemic to the Greek island of Crete, widely used for tea preparation, medicinal purposes, and food flavoring, as well as an ornamental plant. The aim of this work was to introduce the species to the green roof sector while serving urban agriculture. Thus, its growth potential was investigated, along with the content of nutrients (N, P, K, Na) and the accumulation of heavy metals (Cu, Pb, Ni, Mn, Zn, Fe) in its tissues, in two cultivation sites in Athens, Greece, i.e., an extensive green roof and at ground level next to a moderate traffic road. Cultivation took place in plastic containers with a green roof infrastructure fitted, in two substrate types (grape marc compost, perlite, and pumice 3:3:4 v/v, and grape marc compost, perlite, pumice, and soil 3:3:2:2 v/v), with 10 cm depth. Plant growth was favored by the soil substrate, but it was also satisfactory in the soilless one. Cultivation site affected heavy metal accumulation, resulting in higher concentrations both in leaves and in flowers at street level, while no differences were observed in roots. Washing the tissues reduced heavy metal concentrations only in leaves produced at the street level. Substrate type significantly affected Mn concentration in all plant tissues and Fe in roots, with the highest values measured in the soil substrate. Thus, O. dictamnus could be effectively cultivated in sustainable green roofs, better on a soilless substrate to lower construction weight. Careful selection of the cultivation site could minimize contamination with environmental pollutants if human consumption is also desired.
37
Deepa, Velagala Lakshmi, Himasai Reddy Vanga, Naveena Kadali, Sravyasai Divve, Vemana Sravya, and Roopa Sravya Kapa. "Effect of prewarming and continuous warming on tissue dissolving ability of Triton™ versus Twin Kleen™: An in vitro study." Journal of Conservative Dentistry and Endodontics 27, no. 1 (January 2024): 100–104. http://dx.doi.org/10.4103/jcde.jcde_201_23.
Full textAbstract:
Abstract Context: TwinKleen™ and Triton™ are newer all-in-one irrigants that have simultaneous action on both organic and inorganic contents. Studies comparing their tissue dissolving ability (TDA) either at room temperature (RT) or on prewarming (PW) and continuous warming (CW) are not yet reported. Aims: To evaluate and compare the effect of 3% sodium hypochlorite (NaOCl), Twin Kleen™, and Triton™, on the bovine TDA. Materials and Methods: One hundred and twenty tissue specimens (size 4 mm × 4 mm × 2 mm and weight 37 ± 3 mg) were divided into Group 1, normal saline (negative control); Group 2, 3% NaOCl (positive control); Group 3, Twin Kleen™; and Group 4, Triton™ (n = 30) Each group is further divided into three subgroups with ten samples each as sub group a – at room temperature (RT), sub group b – on pre warming (PW) and sub group c– on continuous warming (CW), Tissue specimens were immersed in test tubes with 5 ml of respective irrigants replenished thrice every 15 min. The percentage difference in tissue weights was calculated after 5, 10, and 15 min. Statistical Analysis Used: Multiple intergroup comparisons were done using Tukey’s multiple-comparison test, using SPSS software version 23.0. Results: Both Triton™ and 3% NaOCl showed significantly higher dissolution than normal saline and Twin Kleen™ on CW followed by PW than at RT. Twin Kleen™ showed significantly less dissolution at all the tested temperatures. Conclusions: Heating enhances the TDA of Triton™ and 3% NaOCl but not Twin Kleen™. CW showed significantly higher dissolution than PW.
38
Skopin, I. I., P. V. Kakhktsyan, M. S. Latyshev, D. V. Murysova, T. A. Kupriy, I. A. Zhangeriev, E. V. Khasigova, and L. Zh Enokyan. "Redo aortic root operations in late prosthetic endocarditis: clinical case series." Patologiya krovoobrashcheniya i kardiokhirurgiya 23, no. 4 (December 27, 2019): 73. http://dx.doi.org/10.21688/1681-3472-2019-4-73-82.
Full textAbstract:
<p>Prosthetic aortic valve endocarditis is a severe disease that quickly leads to heart failure. Owing to microorganisms and their toxins constantly entering the bloodstream, bypassing biological barriers, and hemodynamic disturbances, systemic embolism develops quite quickly, leading to sepsis and multi-organ failure. Conservative antibiotic therapy is often not effective because the infectious focus is located in the avascular zone. The presence of an implanted foreign body promotes adhesion of bacteria on the surface of the prosthetic tissue with simultaneous isolation from the action of phagocytes. Conservative treatment of prosthetic infectious endocarditis has an extremely unfavourable prognosis. Hospital mortality without operation is approximately 80%. Operations for prosthetic infectious endocarditis of the aortic valve are technically complex and require a highly qualified operating surgeon. The most difficult operations involve extension of the abscess to the aortic root, area of mitralaortic continuity and left ventricular outflow tract. In such situations, it is necessary to perform complex reconstructive operations on the aortic root, mitral-aortic continuity and left ventricular outflow tract. This study presents an overview of a series of complex redo operations on the aortic root and the ascending aorta in late prosthetic infectious endocarditis, with an analysis of the main tactical and technical aspects of the operations. Moreover, similar operations can be performed with good results by an experienced cardiac surgeon. In this case, it is necessary that prior to operation, the surgeon develops an algorithm of actions and determines 1) optimal access to the heart, 2) perfusion scheme, 3) type of implantable conduit, 4) cardiolysis performance features, 5) myocardial protection scheme and 6) features of the treatment of the infectious focus.</p><p>Received 29 October 2019. Revised 19 December 2019. Accepted 23 December 2019.</p><p><strong>Funding:</strong> The study did not have sponsorship.</p><p><strong>Conflict of interest:</strong> Authors declare no conflict of interest.</p><p><strong>Author contributions</strong><br />Drafting the article: I.I. Skopin, P.V. Kakhktsyan, M.S. Latyshev, D.V. Murysova, T.A. Kupriy, I.A. Zhangeriev<br />Critical revision of the article: I.I. Skopin, P.V. Kakhktsyan, M.S. Latyshev, D.V. Murysova, T.A. Kupriy, I.A. Zhangeriev, E.V. Khasigova, L.Zh. Enokyan<br />Surgical treatment I.I. Skopin, P.V. Kakhktsyan<br />Diagnostics: L.Zh. Enokyan<br />Treatment: D.V. Murysova, T.A. Kupriy<br />Assistance in surgery: M.S. Latyshev, E.V. Khasigova<br />Final approval of the version to be published: I.I. Skopin, P.V. Kakhktsyan, M.S. Latyshev, D.V. Murysova, T.A. Kupriy, I.A. Zhangeriev, E.V. Khasigova, L.Zh. Enokyan</p>
39
Okoth, Elizabeth A., Zehua Zhou, Benson Ongarora, Alyssa Stutes, J. Michael Mathis, and M. Graça H. Vicente. "Synthesis and investigation of phthalocyanine-biotin conjugates." Journal of Porphyrins and Phthalocyanines 23, no. 01n02 (January 2019): 125–35. http://dx.doi.org/10.1142/s1088424619500056.
Full textAbstract:
An isothiocyanato-functionalized phthalocyanine (Pc) was synthesized in good yield from the corresponding amine-substituted Pc. This Pc reacted with ethanolamine, biotin hydrazine, and biotin diethylamine under mild conditions (room temperature in DMF or DMSO in the presence of TEA) to produce the corresponding thiourea products in 60–75% yields. All Pcs showed intense Q absorptions in DMF around 677 nm, emissions centered at 683 nm, and fluorescence quantum yields in the range 0.18–0.27. The Pcs were phototoxic to human carcinoma HEp2 cells (IC[Formula: see text] [Formula: see text] 7 at 1.5 J/cm[Formula: see text] and localized in multiple organelles, including the lysosomes, Golgi and ER. One biotin-Pc conjugate was injected via tail vein into nude mice bearing HT-29 tumors and demonstrated selective localization in the tumor tissue.
40
Chatterjee, Moniya, Sumanti Gupta, Anirban Bhar, and Sampa Das. "Optimization of an Efficient Protein Extraction Protocol Compatible with Two-Dimensional Electrophoresis and Mass Spectrometry from Recalcitrant Phenolic Rich Roots of Chickpea (Cicer arietinum L.)." International Journal of Proteomics 2012 (October 31, 2012): 1–10. http://dx.doi.org/10.1155/2012/536963.
Full textAbstract:
Two-dimensional electrophoresis and mass spectrometry are undoubtedly two essential tools popularly used in proteomic analyses. Utilization of these techniques however largely depends on efficient and optimized sample preparation, regarded as one of the most crucial steps for recovering maximum amount of reliable information. The present study highlights the optimization of an effective and efficient protocol, capable of extraction of root proteins from recalcitrant phenolic rich tissues of chickpea. The widely applicable TCA-acetone and phenol-based methods have been comparatively evaluated, amongst which the latter appeared to be better suited for the sample. The phenol extraction-based method further complemented with sodium dodecyl sulphate (SDS) and pulsatory treatments proved to be the most suitable method represented by greatest spot number, good resolution, and spot intensities. All the randomly selected spots showed successful identification when subjected to further downstream MALDI-TOF and MS/MS analyses. Hence, the information obtained collectively proposes the present protein extraction protocol to be an effective one that could be applicable for recalcitrant leguminous root samples.
41
Essebbahi, Issam, Chadia Ouazzani, Abdallah Moustaghfir, Abdallah Dami, and Lhoussine Balouch. "Analyses physicochimiques de différents thés commerciaux et risque de l’excès de fluor chez la population au Maroc." International Journal of Biological and Chemical Sciences 14, no. 4 (August 17, 2020): 1203–13. http://dx.doi.org/10.4314/ijbcs.v14i4.4.
Full textAbstract:
Sous la forme de fluorure, le fluor entre dans la constitution des tissus durs comme les dents, les os et les cartilages. L’apport excessif en fluor pendant plusieurs mois ou plusieurs années lors de la période de formation des dents peut provoquer la fluorose. Certains aliments habituellement consommés au Maroc sont riches en fluor. Les traitements industriels de transformation, préparation et conservation mettent à la disposition du consommateur des aliments de coût moins chers et de compositions variables qui peuvent être nuisibles à la santé buccale. L’étude des qualités physicochimiques de différentes sources alimentaires de fluor constituées de différents thés noirs, verts, d’eaux de puits consommés par la population marocaine permet de dévoiler la corrélation entre la consommation des aliments riches en fluor et l’apparition de la fluorose dentaire. Différentes de tisanes de granules de 12 thés verts et noirs ont été préparés selon la variation de la durée d’infusion et du mode d’ébullition. Les teneurs de fluor, calcium, chlorures ont été déterminées par les méthodes spectrophotométriques sur 17 échantillons de thés verts et noirs commercialisés, thés glacés, thés de distributeur automatique, thé de buvette, thé de préparation familiale. La teneur en fluor a été déterminée sur 3 échantillons des eaux de puits, 3 eaux d’assainissement urbain de la région de Skhirat Témara afin de déterminer l’apport de fluor contenu dans l’eau de préparation des tisanes. Les analyses physicochimiques révèlent des taux de calcium de 14 à 60 mg/l, chlorures (14 à 75 mg/l) et de fluor (0,93 à 2,7 mg/l) chez les différents thés verts et noirs étudiés, thé de distributeur automatique, thé de buvette et familiale. Les analyses des taux de fluor de 3 échantillons de thés verts marquent Sultan, Menara, Dahmis et un thé noir Earl Grey révèlent des valeurs supérieures aux normes recommandées pour les enfants et les adultes. Le taux de fluor du thé de la buvette est supérieur à celui du thé de distributeur automatique et de préparation familiale. Ces résultats permettent de prévenir la population face au risque d’atteinte de la fluorose dentaire, en limitant la quantité de fluor ingérée par les aliments consommés. Les analyses des niveaux de fluor de tous les types de produits de thés et des eaux de préparation des thés permettront de disposer de mesures de protection de consommation excessive de fluor.Mots clés : Fluor, aliments, thés, Maroc, excès, risques, fluorose
English Title: Physicochemical analyzes of different commercial teas and risk of excess fluorine in the population in Morocco
In the form of fluoride, fluorine enters into the constitution of hard tissues such as teeth, bones and cartilage. Excessive intake of fluoride for several months or years during the period of tooth formation can cause fluorosis. Some foods usually consumed in Morocco are rich in fluorine. The industrial treatments of preparation, transformations make available to the consumer cheaper foods of variable composition which can be harmful to oral health. The study of physicochemical qualities of different food sources of fluorine consisting of different black teas, green teas and well water consumed by the population reveals a correlation between the consumption of foods rich in fluorine and the appearance of dental fluorosis. Different preparations of herbal teas from granules of 12 green and black teas were prepared according the variation of the infusion time, the boiling mode. The contents of fluorine, calcium, chlorides were determined by spectrophotometric methods on 17 samples of green and black teas from vending machines, refreshment tea, family preparation tea. The fluorine content was determined on 3 samples of well water, 3 urban sanitation water from the Skhirat Temara region in order to determine the fluorine content contained in the water for preparing herbal teas. The physicochemical analyzes reveal levels of Calcium (14 to 60 mg/l), Chlorides (14 to 75 mg/l) and fluorine (0.93 to 2.7 mg/l) in the various green and black teas studied, tea vending machine, refreshment and family tea. The analyzes of the fluoride levels of three samples of marketed green teas Sultan, Menara, Dahmis and an Earl Gray black tea reveal values higher than the recommended standards for children’s and adults. The fluoride level of the tea in the refreshment room is higher than that of the vending machine and family preparation tea. These results make it possible to warn the population facing the risk of developing dental fluorosis, by limiting the amount of fluorine ingested by the consumed food. Analyzes of fluoride levels of all types of tea products and tea preparation waters will provide measures to protect against excessive fluoride consumption.
Keywords: Fluorine, foods, teas, Morocco, excess, risk, fluorosis.
42
Kumar, Dinesh, R. Guna, and E. Abbirami. "Anti-oxidant and Anti-inflammatory Properties of Stem and Root Extracts of Cissus quadrangularis (Veldt Grape)." Asian Journal of Engineering and Applied Technology 8, no. 1 (February 5, 2019): 15–19. http://dx.doi.org/10.51983/ajeat-2019.8.1.1066.
Full textAbstract:
Free radicals are unstable, highly reactive molecules, creates oxidative stress in our body by attacking healthy cells and tissue biomolecules. They are usually neutralized by the antioxidant mechanisms in our system. When the antioxidant mechanism fails to stabilize the radicals, we need external antioxidants to protect our cells from oxidative damage. The objective of present study is to evaluate the antioxidant and anti-inflammatory properties of stem and root extracts of the plant Cissus quadrangularis. Stem and root powders of CQ was extracted with different solvent and they were tested against the synthetic free radical DPPH, ABTS, NO, H2O2 and FRAP with the reference standard BHT. The in vitro anti-inflammatory activity assay was also performed for all the extracts along with the reference standard naproxen. The 50 percentage of inhibitory concentration (IC50-μg/ml of extract) values of ethanol fraction from both stem and root extract was found to be in DPPH- (IC50: 32±0.07 & 28±0.02), ABTS- (IC50: 115±0.22 & 120±0.06), NO- (IC50: 13±0.05 & 47±0.13), H2O2- (IC50: 21±0.08 & 28±0.09), TAA- (PI: 73±0.16 & 66±0.22) and the protein denaturation assay showed the ethanol fraction has protective activity levels of 220±0.03 & 277±0.22 in stem and root extracts respectively. Results obtained from this study suggested that both stem and root extracts of CQ possesses potential antioxidant and anti-inflammatory properties.
43
VILHENA, MILCA B., MÔNICA R. FRANCO, DAIANA SCHMIDT, GISELLE CARVALHO, and RICARDO A. AZEVEDO. "Evaluation of protein extraction methods for enhanced proteomic analysis of tomato leaves and roots." Anais da Academia Brasileira de Ciências 87, no. 3 (August 25, 2015): 1853–63. http://dx.doi.org/10.1590/0001-3765201520150116.
Full textAbstract:
Proteomics is an outstanding area in science whose increasing application has advanced to distinct purposes. A crucial aspect to achieve a good proteome resolution is the establishment of a methodology that results in the best quality and wide range representation of total proteins. Another important aspect is that in many studies, limited amounts of tissue and total protein in the tissue to be studied are found, making difficult the analysis. In order to test different parameters, combinations using minimum amount of tissue with 4 protocols for protein extraction from tomato (Solanum lycopersicum L.) leaves and roots were evaluated with special attention to their capacity for removing interferents and achieving suitable resolution in bidimensional gel electrophoresis, as well as satisfactory protein yield. Evaluation of the extraction protocols revealed large protein yield differences obtained for each one. TCA/acetone was shown to be the most efficient protocol, which allowed detection of 211 spots for leaves and 336 for roots using 500 µg of leaf protein and 800 µg of root protein per gel.
44
Sabbatini, Paolo, and James A. Flore. "Effect of Crop Load on Diurnal Leaf Photosynthesis, Stomatal Conductance, and Annual Carbon Isotope Composition of `Imperial Gala' Apple Tree." HortScience 40, no. 4 (July 2005): 1096C—1096. http://dx.doi.org/10.21273/hortsci.40.4.1096c.
Full textAbstract:
The naturally occurring carbon isotope composition (or 13C: 12C ratio, expressed with the notation d13C) of plant tissue may be used as an indicator of water use efficiency during plant growth. d13C has been shown to be an effective tool to study physiological response of plant to environmental conditions, especially water stress. The objective of this work was to test if d13C could be an indicator of carbon limitations or a low source: sink ratio. Trees of `Imperial Gala'/Bud 9 (n = 12), 6-years-old, field grown at the Clarksville Horticultural Research Station (Clarksville, Miss.), were assessed with different crop load (LCL = Low Crop Load, 0.76 ± 0.44 fruit per trunk sectional area (TCA); NCL = Normal Crop Load, 7.25 ± 1.83 fruit/TCA; HCL = High Crop Load, 15.83 ± 1.76 fruit/TCA) and leaf: fruit ratio (LCL: 52.78 ± 8.55, NCL: 13.33 ± 3.06, HCL; 4.31 ± 0.68) immediately following June drop. Net photosynthetic rate of leaves were monitored during the season and elevated rates were observed in NCL and HCL and correlated with the fruiting process. Photosynthesis was inhibited in LCL more in the afternoon (from 20% to 42% in relation to NCL) than in the morning (from 5% to 20%) and this was positively correlated with crop sink strength. Variations of the stable carbon isotope composition of roots (fine and coarse), fruit, leaves, and current-year stems were examined. The d13C varied by tissue (fruit > shoot and leaf > root) and in relation to the level of crop load (d13C‰ in fruit: LCL –23.513 ± 0.248, NCL –24.891 ± 0.594; and HCL –24.935 ± 0.375). These results may have implications for analysis of isotopic signals in carbohydrate stress and fractionation steps will be discussed.
45
Fujii, Takayuki, Eun-Jae Lee, Yukino Miyachi, Ryo Yamasaki, Young-Min Lim, Kyoko Iinuma, Ayako Sakoda, Kwang-Kuk Kim, and Jun-ichi Kira. "Antiplexin D1 Antibodies Relate to Small Fiber Neuropathy and Induce Neuropathic Pain in Animals." Neurology - Neuroimmunology Neuroinflammation 8, no. 5 (June 7, 2021): e1028. http://dx.doi.org/10.1212/nxi.0000000000001028.
Full textAbstract:
ObjectivesTo assess the prevalence of antiplexin D1 antibodies (plexin D1-immunoglobulin G [IgG]) in small fiber neuropathy (SFN) and the effects of these antibodies in vivo.MethodsWe developed an ELISA for plexin D1-IgG using a recombinant extracellular domain of human plexin D1 containing the major epitope and sera from 58 subjects previously studied with a standard tissue-based indirect immunofluorescence assay (TBA). We screened 63 patients with probable SFN and 55 healthy controls (HCs) for serum plexin D1-IgG using ELISA. The results were confirmed by TBA. IgG from 3 plexin D1-IgG-positive patients, 2 plexin D1-IgG-negative inflammatory disease controls, and 2 HCs was intrathecally injected into mice, which were assessed for mechanical and thermal hypersensitivity 24 and 48 hours after injection.ResultsThe ELISA had 75% sensitivity and 100% specificity using the TBA as a standard, and the coincidence rate of ELISA to TBA was 96.6% (56/58). The frequency of plexin D1-IgG was higher in patients with SFN than in HCs (12.7% [8/63] vs 0.0% [0/55], p = 0.007). Purified IgG from all 3 plexin D1-IgG-positive patients, but not 2 plexin D1-IgG-negative patients, induced significant mechanical and/or thermal hypersensitivity compared with IgG from HCs. In mice injected with plexin D1-IgG-positive but not D1-IgG-negative patient IgG, phosphorylated extracellular signal-regulated protein kinase immunoreactivity, an activation marker, was confined to small dorsal root ganglion neurons and was significantly more abundant than in mice injected with HC IgG.ConclusionsPlexin D1-IgG is pathogenic but with low prevalence and is a potential biomarker for immunotherapy in SFN.
46
Horn, Andrew, Jeremy Saller, Daniel J. Cuttica, Xue Geng, and Steven Neufeld. "Utility of Dehydrated Human Amniotic Membrane (DHAM) in Total Ankle Arthroplasty." Foot & Ankle International 41, no. 5 (February 10, 2020): 513–20. http://dx.doi.org/10.1177/1071100720903726.
Full textAbstract:
Background: Wound complications after total ankle arthroplasty (TAA) are a common postoperative complication occurring in 14% to 66% of all surgeries. Soft tissue breakdown along the anterior incision can cause exposure of anterior tendons and implant, and adhesions of the extensor tendons of the foot. Recent publications have advocated for the implantation of dehydrated human amniotic membrane (DHAM) allograft during closure of anterior ankle incisions during TAA. The goal of this study was to determine whether implantation of DHAM allograft in TAAs decreased overall postoperative wound complications. Methods: One hundred seventy patients with end-stage ankle arthritis refractory to conservative management underwent TAA with a standard anterior approach by 1 of 3 board-certified foot and ankle orthopedic surgeons. Ninety-one patients underwent closure of the anterior incision with addition of DHAM, whereas 79 patients served as the control (no addition of DHAM). The primary endpoints considered were postoperative complications and reoperation. Included in the postoperative complications was return to the operating room, postoperative plastic surgery intervention, wound communication with the implant, removal of the implant, neurolysis, tendon debridement, and extensor hallucis longus contracture/adhesions. Results: In the analysis of our demographically homogenous cohorts, there was no statistically significant difference in any postoperative complications between patients closed with DHAM and controls. Return to the operating room occurred in 8.9% of controls and 15.4% of the DHAM group ( P = .291). Similarly, there was no statistically significant difference in postoperative plastic surgery, wound communication with the implant, implant removal, neurolysis, and tendon debridement between the control and DHAM groups. Conclusion: The application of DHAM theoretically acts to decrease overall wound complications in TAA. The use of DHAM preceding wound closure in TAA did not show a statistically significant reduction in overall wound complications in our retrospective analysis. Further study, including prospective randomized studies, is needed to further investigate the effectiveness of DHAM in reducing wound complications in TAAs. Level of Evidence: Level III, retrospective cohort study.
47
Li, X., K. Guo, Y. Zhang, X. Yan, and J. Zheng. "First Report of the Stubby Root Nematode, Paratrichodorus minor, in Mainland China." Plant Disease 94, no. 3 (March 2010): 376. http://dx.doi.org/10.1094/pdis-94-3-0376a.
Full textAbstract:
The stubby root nematode, Paratrichodorus minor (Colbran, 1956) Siddiqi, 1974, is an economically important species. It not only causes direct damage to the meristemic tissues of plants, but also can be a vector of Tobacco rattle virus and Pepper ringspot virus (2). It has been documented in Afghanistan, Argentina, Australia, Brazil, Canary Islands, Cuba, Egypt, Fiji, India, Israel, Ivory Coast, Japan, Java, Mauritania, New Zealand, Nicaragua, Philippines, Puerto Rico, Senegal, South Africa, Taiwan, Upper Volta, the United States, the former USSR, and Venezuela (1). During a recent investigation on Trichodoridae occurring in China, eight stubby root nematode populations were detected in Hainan, Yunnan, and Fujian provinces in the rhizospheres of eggplant (Solanum melongena), Chinaberry (Melia azedarach), lettuce (Lactuca sativa), longan (Dimocarpus longan), peach (Prunus persica), pear (Pyrus sp.), and walnut (Juglans regia) in soils ranging from clay to sand. The eight populations had similar morphological and molecular characters. The females were cigar shaped with rod-shaped vaginal sclerotization parallel to the longitudinal body axis with a quadrangular vagina in side view having a short vulval slit. The key morphometrics of females were consistent with those of P. minor: body length, 631 to 757 μm; body diameter, 27 to 43 μm; onchiostyle, 35 to 36 μm; a, 18 to 24; b, 4.9 to 5.5; v%, 53 to 55; length of vagina, 10.8 to 11.1 μm; and size of vaginal pieces, 1.7 to 1.9 μm. Males in P. minor are rare and were not found in any of the eight populations. Partial sequences of the 18s RNA gene of each population were amplified with forward primer 5′-AAA GAT TAA GCC ATG CAT G-3′ (2), and reverse primer 5′-AGT CAA ATT AAG CCG CAG-3′ (3), which yielded a PCR fragment of 1,153 bp. PCR products from all eight populations were sequenced and submitted to GenBank and assigned Accession Nos. GQ995703, GQ995704, GQ995705, GQ995706, GQ995707, GQ995708, GQ995709, and GQ995710. The sequences exhibited 99.8 to 100% similarity with those of P. minor isolates DQ345526, AM269897, AJ438052, AJ438053, and AJ438058 from GenBank. Morphological and molecular identification confirmed that all populations were P. minor. To our knowledge, this is the first report of P. minor in mainland China. References: (1) K. Boutsika et al. Nematology 6:145, 2004. (2) W. Decramer. The Family Trichodiridae: Stubby Root and Virus Vector Nematodes. Kluwer Academic Publishers, Dordrecht, the Netherlands, 1995. (3) I. S. Waite et al. Soil Biol. Biochem. 35:1165, 2003.
48
Eskalen, A., A. Gonzalez, D. H. Wang, M. Twizeyimana, J. S. Mayorquin, and S. C. Lynch. "First Report of a Fusarium sp. and Its Vector Tea Shot Hole Borer (Euwallacea fornicatus) Causing Fusarium Dieback on Avocado in California." Plant Disease 96, no. 7 (July 2012): 1070. http://dx.doi.org/10.1094/pdis-03-12-0276-pdn.
Full textAbstract:
Per capita consumption of avocado in the United States has nearly doubled between 2000 and 2010. The California avocado industry supplies almost 40% of U.S. demand and the remaining 60% is supplied by imports from Latin America and New Zealand. The Tea Shot Hole Borer (TSHB) is an ambrosia beetle from Asia that forms a symbiosis with a new, yet undescribed Fusarium sp. and is a serious problem for the Israeli avocado industry (3). The beetle also causes severe damage on the branches of tea (Camelia sinensis) in Sri Lanka and India (1). In California, TSHB was first reported on black locust (Robinia pseudoacacia) in 2003, but there are no records of fungal damage (4). In 2012, nine backyard avocado trees (cvs. Hass, Bacon, Fuerte, and Nabal) exhibiting branch dieback were observed throughout the residential neighborhoods of South Gate, Downey, and Pico Rivera in Los Angeles County. Upon inspection, symptoms of white powdery exudate, either dry or surrounded by wet discoloration of the outer bark in association with a single beetle exit hole, were found on the trunk and main branches of the tree. Examination of the cortex and wood under the exit hole revealed brown discolored necrosis. The TSHB was also found within galleries that were 1 to 4 cm long going against the grain. Symptomatic cortex and sapwood tissues were plated onto potato dextrose agar amended with 0.01% tetracycline (PDA-tet). The TSHB was dissected and plated onto PDA-tet after surface disinfestation following methods described by Kajimura and Hijii (2). After 5 days of incubation at room temperature, regular fungal colonies with aerial mycelia and reddish brown margins were produced. Single spore isolations were used to establish pure culture of the fungus. Fifty conidia were hyaline, clavate with a rounded apex, and initially aseptate (4.1 to 12.0 × 2.4 to 4.1 μm) becoming one- to three-septate (7.6 to 15.1 × 2.8 to 4.5 μm, 9.2 to 17.2 × 3.4 to 4.8 μm, and 13.5 to 17.6 × 4.3 to 4.7 μm, respectively). Identity of the fungal isolates was determined by amplification of the rDNA genes with primers ITS4/5 and EF1/2, respectively. Sequences were deposited into GenBank under Accession Nos. JQ723753, JQ723760, JQ723756, and JQ723763. A BLASTn search revealed 100% similarity to Fusarium sp. (Accession Nos. JQ038020 and JQ038013). Detached green shoots of healthy 1-year-old avocado were wounded to a depth of 1 to 2 mm and 5-mm mycelial plugs from 5-day-old cultures (UCR 1781 and UCR 1837) were placed mycelial side down onto the freshly wounded surfaces and then wrapped with Parafilm. Control shoots were inoculated with sterile agar plugs and five replicates per treatment were used. Shoots were incubated at 25 ± 1°C in moist chambers for 3 weeks. Lesions were observed on all inoculated shoots except for the control. Mean lesion lengths were 10.7 and 12.8 cm for UCR1781 and UCR1837, respectively, and were significantly different (P ≤ 0.05) from the control. Both isolates were reisolated from 100% of symptomatic tissues of inoculated shoots to complete Koch's postulates. This experiment was conducted twice and similar results were obtained. To our knowledge, this is the first report of Fusarium sp. and its vector E. fornicatus causing Fusarium dieback on Avocado in California. References: (1) W. Danthanarayana. Tea Quarterly 39:61, 1968. (2) H. Kajimura and N. Hijii. Ecol. Res. 7:107, 1992; (3) Mendel et al., Phytoparasitica, DOI 10.1007/s12600-012-0223-7, 2012. (4) R. J. Rabaglia. Annals Entomol. Soc. Amer. 99:1034, 2006.
49
Lee, Jieun, Jung Eun Kim, Sanjun Lee, Tae-Kyeong Lee, In Hee Kim, So Hee Yoon, Mira Yoo, et al. "Abstract 5322: High throughput chemotherapeutic drug screening system for gastric cancer: cure-GA." Cancer Research 83, no. 7_Supplement (April 4, 2023): 5322. http://dx.doi.org/10.1158/1538-7445.am2023-5322.
Full textAbstract:
Abstract To discover clinically applicable anticancer drugs and predict therapeutic response for advanced gastric cancer, we developed a high-throughput drug (HTD) screening system that could rapidly evaluate drug reactivity using 3D cultured primary cells derived from gastric cancer (GC) patients. Primary cancer cells were isolated from fresh surgical specimens that resected from 143 GC patients using Gentle Max tissue dissociation system. Primary cells were mixed with Matrigel, and placed on a micropillar for three-dimensional (3D) culture. After the primary cells were stabilized in the complete culture medium (CCM) than added various chemotherapeutic drugs containing 5-FU, Oxaliplatin, and Paclitaxel in CCM and incubated for 7 days. Cell viability was determined through calcein staining and quantified scanned images. The IC50 for each drug was calculated by a sigmoidal dose-response curve, using the GraphPad Prism 9 program. The average weight of gastric cancer tissue used in the experiment was 300 mg (75 mg ~ 1930 mg), and the average number of dissociated viable cells for each tissue was 3.9 × 10^6 cells/case. About 2.4 × 10^5 live cell was required per drug, we were able to obtain an average of 6.4 (Min.2, Max 14) drug reactivity data per tissue using the HTD screening system. GC tissues obtained from the operating room were dissociated within 16 hours and then loaded into the HTS system within 3 hours. Cells were stabilized for 1 day in 3D culture plate and exposed to the drug for 7 days, and then data reports were made within 3 days. As a result, it was possible to obtain within 14 days from fresh surgical GC tissue to drug response data. Additionally, we confirmed that 3D cultured primary cells derived from GC tissues consistently preserved primary characters using IHC. Similar to their parental cancer tissue, GC 3D cultured primary cells derived from adenocarcinoma large glandular patterns and retain the expression of some marker proteins. In this study, we evaluated the drug response data for 101 cases (success rate 71%; 101/143) to 5-FU, Oxaliplatin, and Palitaxel, etc. using the HTD screening system and it was confirmed that individual patient had a difference response to each drug. Here we established the HTD screening system using 3D cultured GC patient derived primary cells. The advantages of this system were that it is the first model system that directly used patient-derived primary cells for drug screening, and it can rapidly evaluate drug reactivity to various anticancer drugs within 10 days. The HTD screening system based on patient-derived primary cells can provide that information to predict drug response and allow for finding more appropriate therapy for each patient. Citation Format: Jieun Lee, Jung Eun Kim, Sanjun Lee, Tae-Kyeong Lee, In Hee Kim, So Hee Yoon, Mira Yoo, Eunju Lee, Doo-Young Hwang, So Hyun Kang, Bo Sung Ku, Dong Woo Lee, Young Suk Park, Ji-Won K, Jin Won Kim, Sang-Hoon Ahn, Keun-Wook Lee, Hyung-Ho Kim, Hyun Jung Oh, Yun-Suhk Suh. High throughput chemotherapeutic drug screening system for gastric cancer: cure-GA. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 5322.
50
Dai, Y. C. "First Report of Laminated Root Rot on Sabina przewalskii Caused by Phellinus weirii sensu stricto in China." Plant Disease 88, no. 5 (May 2004): 573. http://dx.doi.org/10.1094/pdis.2004.88.5.573c.
Full textAbstract:
Members of the Phellinus weirii complex cause laminated root rot of living conifers. The cedar type (P. weirii (Murrill) Gilb. sensu stricto) of the complex is usually found on species of the Cupressaceae family, especially Thuja plicata in western North America, and the Douglas-fir type (P. sulphurascens Pilát) is found on species of the Pinaceae family (1,2,3). Outside North America, P. weirii occurs on species of Juniperus in the Ural Mountains, and P. sulphurascens occurs on other conifers in eastern Asia, including China (1). During a field inventory of wood-decay fungi in western China in 2003, laminated root rot of Sabina przewalskii (synonym Juniperus przewalskii) was found in natural forests of the Qilian Mountains in Qinghai Province (37°36′N and 102°15′E). Trees were approximately 80 to 150 years old and occurred in pure stands. Distinct disease patches that were as much as one hectare consisted of dead-standing and symptomatic trees, suggesting that the fungus spread by root contact. Symptomatic trees showed slow growth, thin crowns, and chlorotic foliage. After cutting several of the symptomatic trees, cambial necrosis and wood decay were found, and the trees apparently died when the cambial necrosis girdled the base of the trees. The wood of infected trees was reddish brown at the early stages of decay and later had numerous small cavities and separated into sheets at the junction of annual rings. Perennial, poroid, resupinate, dark brown basidiocarps formed on the root surface of dead trees. The basidiocarps had a monomitic hyphal system, hyphae without clamp connections, trama tissue with hyphoid setae, and thin-walled, hyaline, smooth, ellipsoid basidiospores. The fungus was identified as P. weirii and distinguished from P. sulphurascens by its perennial basidiocarps, smaller pores (5 to 8 versus 4 to 5 per mm), and narrower hyphoid setae (4 to 6 versus 5 to 10 μm in diameter). P. weirii also resembles P. ferrugineofuscus (P. Karst.) Bourdot in macro-morphology, but the latter species is a saprophyte and has allantoid to almost lunate basidiospores. The studied specimens of P. weirii and P. sulphurascens are preserved at the herbaria of the Botanical Museum of the University of Helsinki, the Institute of Applied Ecology, and the Chinese Academy of Sciences as DAOM 8734, Lowe 6960, TAA 52744, 55644, and 103812, and Dai 988, 2053, 2061, 2527, and 5067. To my knowledge, this is the first report of P. weirii sensu stricto from China and the first report of laminated root rot on S. przewalskii. References: (1) Y. C. Dai and G. F. Qin. Fungal Sci. 13:101, 1998. (2) E. M. Hansen et al. Species limits for Phellinus weirii. Pages 119–127 in: Root and butt rots of forest tress. Int. Conf. Root and Butt Rots, INRA, France, 1998. (3) M. J. Larsen et al. Mycologia 86:121, 1994.