Journal articles on the topic 'Non-lethal concentration'
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1
Lucić, A., V. Bradamante, M. Peraica, B. Radić, A.-M. Domijan, and R. Fuchs. "Changes in plasma lipids after a non-lethal dose of cycloheximide in rats." Human & Experimental Toxicology 22, no. 5 (May 2003): 245–48. http://dx.doi.org/10.1191/0960327103ht355oa.
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This paper describes a study of the effect of a single intraperitoneal non-lethal dose of cycloheximide (CHM; 2.0 mg/kg body weight) on the concentration of plasma lipids and lipoproteins in male rats killed one, two, three, four and nine days after receiving the dose. The concentration of triglycerides, total cholesterol, high-density lipoproteins (HDL)-cholesterol and low-density lipoproteins (LDL)-cholesterol was measured in treated and control animals. The effect of CHM on the concentration of triglycerides, total cholesterol, HDL-cholesterol, and LDL-cholesterol was visible in rat plasma throughout the study. Total cholesterol and HDL-cholesterol concentrations showed the same pattern of changes, probably due to the reversible inhibition of apolipoprotein apo A-I synthesis by CHM. The concentration of triglycerides decreased after a lag period of three days when the reserves of apolipoprotein apo B, the main apolipoprotein of very low-density lipoproteins (VLDL)-cholesterols produced in the liver, were consumed.
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Man, Yonghong, Yunhao Liu, Chuanzhen Xiong, Yang Zhang, and Ling Zhang. "Non-Lethal Concentrations of CdCl2 Cause Marked Alternations in Cellular Stress Responses within Exposed Sertoli Cell Line." Toxics 11, no. 2 (February 9, 2023): 167. http://dx.doi.org/10.3390/toxics11020167.
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Cadmium is a component of ambient metal pollution, which is linked to diverse health issues globally, including male reproductive impairment. Assessments of the acute effects of cadmium on male reproduction systems, such as testes, tend to be based on frank adverse effects, with particular molecular pathways also involved. The relationship between cytotoxicity potential and cellular stress response has been suggested to be one of the many possible drivers of the acute effects of cadmium, but the link remains uncertain. In consequence, there is still much to be learned about the cellular stress response induced by a non-lethal concentration of cadmium in male reproductive cells. The present study used temporal assays to evaluate cellular stress response upon exposure to non-lethal concentrations of Cadmium chloride (CdCl2) in the Sertoli cell line (TM4). The data showed alternations in the expression of genes intimated involved in various cellular stress responses, including endoplasmic reticulum (ER) stress, endoplasmic unfolded protein stress (UPRmt), endoplasmic dynamics, Nrf2-related antioxidative response, autophagy, and metallothionein (MT) expression. Furthermore, these cellular responses interacted and were tightly related to oxidative stress. Thus, the non-lethal concentration of cadmium perturbed the homeostasis of the Sertoli cell line by inducing pleiotropic cellular stresses.
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Gremillion, Paul T., James V. Cizdziel, and Norman R. Cody. "Caudal Fin Mercury as a Non-Lethal Predictor of Fish-Muscle Mercury." Environmental Chemistry 2, no. 2 (2005): 96. http://dx.doi.org/10.1071/en05018.
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Environmental Context. Surveys to assess the body burden of mercury in fish to support research or contamination advisory programs typically involve capturing and killing fish and analyzing muscle tissue for mercury. Lethal sampling may not be feasible in protected waters or in studies involving threatened or endangered species. We analyzed tail fin samples of two fish species for total mercury and compared results with muscle-tissue mercury and concluded that fin-Hg can be used as a predictor of muscle-Hg. This approach enables catch and release studies for mercury in fish. Abstract. The caudal (tail) fins from 17 walleye (Sander vitreus) and 12 northern pike (Esox lucius) from three northern Arizona lakes (Long Lake, Soldier Lake, and Upper Lake Mary) were analyzed for total-Hg by combustion–atomic absorption spectrometry. Results indicate that the fin contains measurable Hg that correlates with muscle-Hg concentrations. As the body burden of Hg increased, the concentration in the fin increased relative to the muscle. Mercury concentrations also increased with fish length and weight, although the relationship was lake- and species-dependent. Fish from Soldier Lake had the most efficient uptake of Hg, likely due to the trophic structure of the lake or the condition of the fish, but possibly due to an acute source of Hg. Overall, this study demonstrates that caudal fin clippings can be used as a non-lethal predictor of muscle-Hg concentrations, which can reduce the number of fish killed in routine monitoring programs.
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Ryba, S. A., J. L. Lake, J. R. Serbst, A. D. Libby, and S. Ayvazian. "Assessment of caudal fin clip as a non-lethal technique for predicting muscle tissue mercury concentrations in largemouth bass." Environmental Chemistry 5, no. 3 (2008): 200. http://dx.doi.org/10.1071/en08017.
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Environmental context. In the development of fish consumption advisories, fisheries biologists routinely sacrifice fish and analyse muscle fillets in order to determine the extent of mercury contamination. Such lethal techniques may not be suitable for endangered species or limited fish populations from smaller-sized water bodies. We compared the measured total mercury concentrations in tail fin clips to that of muscle fillets and illustrated that tail fin clips may be used as an accurate tool for predicting mercury in muscle tissue. This is the first study on the use of tail fin clips to predict mercury levels in the muscle tissue of largemouth bass with minimal impact on the fish. Abstract. The statistical relationship between total mercury (Hg) concentration in clips from the caudal fin and muscle tissue of largemouth bass (Micropterus salmoides) from 26 freshwater sites in Rhode Island, USA was developed and evaluated to determine the utility of fin clip analysis as a non-lethal and convenient method for predicting mercury concentrations in tissues. The relationship of total Hg concentrations in fin clips and muscle tissue showed an r2 of 0.85 and may be compared with an r2 of 0.89 for Hg concentrations between scales and muscle tissue that was determined in a previous study on largemouth bass. The Hg concentration in fin clip samples (mean = 0.261 μg g–1 (dry)) was more than a factor of twenty greater than in the scale samples (mean = 0.012 μg g–1 (dry)). Therefore, fin clips may be a more responsive non-lethal predictor of muscle-Hg concentrations than scale in fish species which may have reduced Hg concentrations.
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Banaee, M., and M. Zoheiri. "Histopathological changes induced by paraquat on some tissues of gourami fish (Trichogaster trichopterus)." Open Veterinary Journal 5, no. 2 (2013): 36. http://dx.doi.org/10.5455/ovj.2013.v3.i1.p36.
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Paraquat is a contact and non-selective herbicide which is used for controlling a wide range of terrestrial weeds and aquatic plants. A long-term contact with this xenobiotic can potentially lead to injuries in fishes as live non-target organisms. Therefore, the current study aimed to investigate the effect of sub-lethal toxicity of paraquat on the pathology of gill, liver, and spleen tissues in gourami fish (Trichogaster trichopterus). In this study, sub-lethal concentration is determined based on lethal concentration (LC50 : 7.16±0.69, 4.46±0.43, 2.19±0.27 and 1.41±0.17 mg/l of paraquat within 24, 48, 72 and 96 hours, respectively). The experiment was done with four varied concentrations of paraquat (0.0, 0.07, 0.15, and 0.3 mg/l equal 0.0%, 5%, 10% and 20% of nominal value of 96 h LC50) during 3 weeks. The exposed ?sh displayed erratic swimming and became lethargic. The changes in gills were characterized by hypertrophy, epithelial, epithelium increase of gill filament, edema and secondary gill lamella. The liver showed hypotrophy of liver cells, cloudy swelling and formation of cytoplasmic vacuoles in the liver tissue of fish treated with 0.15 and 0.3 mg/l concentrations of paraquat. Disorder in the ellipsoid cell and hemosiderin accumulation in melano-macrophage centers was observed in the spleen tissue of fish exposed to 0.15 and 0.3 mg/l of paraquat.
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I. B., Okey, Ayotunde E. O., and Patrick B. U. "Behavioural Responses and Mortality of Clarias gariepinus Juveniles Exposed to Acute Concentrations of Paraquat." Sumerianz Journal of Agriculture and Veterinary, no. 42 (April 19, 2021): 49–54. http://dx.doi.org/10.47752/sjav.42.49.53.
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Paraquat is the most common contact and non- selective herbicide for exterminating vegetative pest. Fish are ideal sentinels for detecting aquatic pollutants and are largely used as bio indicators of environmental pollution. This study is aimed to determine the behavioural changes, lethal concentrations (LCs) and mean lethal time (MLT) of paraquat exposed to Clarias gariepinus. A 96 hours renewable bioassay was conducted with various paraquat concentrations 0.0, 0.25, 0.50, 0.75, 1.0 and 1.25 mg/l. Behavioural changes and cumulative mortality were observed and recorded at 12, 24, 48, 72 and 96 hour. Behavioural changes such as air gulping, erratic swimming, loss of balance, excessive mucus secretion, discolouration and death were observed with severity increasing as concentration and duration of exposure increases. The LC50 values were decreased from 0.191mg/l (0.171 – 0.222) in 12 hour to 0.107mg/l (0.065 – 0.150) in 96 hour, while relative toxicity factor (TF) was increased from 1 to 1.79 times respectively. The 96hr MLT values were decreased from 91.18 hours (54.09-105.64) at the lowest concentration to 16.22 hours (9.06 – 25.15) at the highest concentration with relative toxicity time (RTT) increasing from 1 to 5.62 times. Herbicide should be apply with caution and studies on the sub lethal effects of paraquat on the haematological, biochemical and histological parameters of C. gariepinus juveniles will be necessary.
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Jones, J., M. B. Hallett, and B. P. Morgan. "Reversible cell damage by T-cell perforins. Calcium influx and propidium iodide uptake into K562 cells in the absence of lysis." Biochemical Journal 267, no. 2 (April 15, 1990): 303–7. http://dx.doi.org/10.1042/bj2670303.
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The non-lethal effects of the lymphocyte-derived pore-forming toxin perforin on the human erythroleukaemia cell line K562 were investigated. By using the fluorescent Ca2+ indicator fura-2, perforin was shown to cause intracellular Ca2+ concentration to rise transiently into the micromolar range in the absence of cell death. By fluorescence-activated cell sorting it was demonstrated that K562 cells took up the membrane-impermeant nuclear stain propidium iodide (PI) when exposed to non-lethal doses of perforin. The permeability to PI was short-lived, confirming the transience of the perforin pore. Analogies with non-lethal effects and recovery processes occurring in nucleated cells exposed to the membrane-attack complex of complement are drawn.
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Ekwall, Björn, Frank A. Barile, Argelia Castano, Cecilia Clemedson, Richard H. Clothier, Paul Dierickx, Barbro Ekwall, et al. "MEIC Evaluation of Acute Systemic Toxicity." Alternatives to Laboratory Animals 26, no. 2_suppl (August 1998): 617–58. http://dx.doi.org/10.1177/026119299802602s03.
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The Multicenter Evaluation of In Vitro Cytotoxicity (MEIC) programme was set up to evaluate the relevance for human acute toxicity of in vitro cytotoxicity tests. At the end of the project in 1996, 29 laboratories had tested all 50 reference chemicals in 61 cytotoxicity assays. Five previous articles have presented the in vitro data and the human database to be used in the evaluation. This article presents three important parts of the final evaluation: a) a comparison of rat and mouse oral LD50 with human acute lethal doses for all 50 chemicals; b) a display of the correlations between IC50 (concentration causing 50% inhibition) values from all 61 assays and three independent sets of human acute lethal blood concentrations, i.e. clinical lethal concentrations, forensic lethal concentrations, and peak concentrations; and c) a series of comparisons between average IC50 values from ten human cell line 24-hour assays and human lethal blood concentrations. In the latter comparisons, results from correlations were linked with known human toxicity data for the chemicals, to provide an understanding of correlative results. This correlative/mechanistic approach had the double purpose of assessing the relevance of the in vitro cytotoxicities, and of testing a series of hypotheses connected with the basal cytotoxicity concept. The results of the studies were as follows. Rat LD50 predictions of human lethal dosage were only relatively good (R2 = 0.61), while mouse LD50s gave a somewhat better prediction (R2 = 0.65). Comparisons performed between IC50 values from the 61 assays and the human lethal peak concentrations demonstrated that human ceil line tests gave the best average results (R2 = 0.64), while mammalian and fish cell tests correlated less well (R2 = 0.52–0.58), followed by non-fish ecotoxicological tests (R2 = 0.36). Most of the 61 assays underpredicted human toxicity for digoxin, malathion, carbon tetrachloride and atropine sulphate. In the correlative/mechanistic study, the 50 chemicals were first separated into three groups: A = fast-acting chemicals with a restricted passage across the blood–brain barrier; B = slow-acting chemicals with a restricted passage across the blood–brain barrier; and C = chemicals which cross the blood–brain barrier freely, while inducing a non-specific excitation/depression of the central nervous system (CNS). The IC50 values for chemicals in group C were divided by a factor of ten to compensate for a hypothetical extra vulnerability of the CNS to cytotoxicity. Finally, the average human cell line IC50 values (24-hour IC50 for groups A and C, and after 48-hour for group B) were compared with relevant human lethal blood concentrations (peak concentrations for groups A and C, and 48-hour concentrations for group B). As a result, in vitro toxicity and in vivo toxicity correlated very well for all groups (R2 = 0.98, 0.82 and 0.85, respectively). No clear overprediction of human toxicity was made by the human cell tests. The human cell line tests underpredicted human toxicity for only four of the 50 chemicals. These outlier chemicals were digoxin, malathion, nicotine and atropine sulphate, all of which have a lethal action in man through interaction with specific target sites not usually found in cell lines. Potassium cyanide has a cellular human lethal action which cannot be measured by standard anaerobic cell lines. The good prediction of the human lethal whole-blood concentration of this chemical was not conclusive, i.e. was probably a “false good correlation”. Another two chemicals in group C resulted in “false good correlations”, i.e. paracetamol and paraquat. The comparisons thus indicated that human cell line cytotoxicities are relevant for the human acute lethal action for 43 of the 50 chemicals. The results strongly support the basal cytotoxicity concept, and further point to the non-specific CNS depression being the obligatory reaction of humans to cytotoxic concentrations of chemicals, provided that the chemicals are able to pass the blood–brain barrier.
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Dlamini, Nomasonto Portia, and Patricks Voua Otomo. "High Rates of Biochar Soil Amendment Cause Increased Incidences of Neurotoxic and Oxidative Stress in Eisenia fetida (Oligochaeta) Exposed to Glyphosate." Applied Sciences 12, no. 5 (February 24, 2022): 2381. http://dx.doi.org/10.3390/app12052381.
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Despite several known beneficial attributes, biochar is suspected to cause harm to soil organisms when present in relatively high quantities in the soil. To determine the potential detrimental effects of biochar, for 96 h, we exposed the earthworm Eisenia fetida to 0, 2, 4 and 8 mg glyphosate (GLY) per kg in non-amended and biochar-amended soil at rates of 5, 10 and 15%. The results indicated that in non-amended soil, survival was significantly decreased in the highest GLY concentration. Although no median lethal concentration (LC50) could be computed due to the lack of sufficient mortality, in the absence of biochar, a lethal concentration 10% (LC10) of 5.540 mg/kg and a lethal concentration 20% (LC20) of 7.067 mg/kg were calculated. In the biochar-amended soil, no mortality occurred in the control and GLY treatments for all three biochar amendment rates. Biomass results showed significant biomass loss in the highest GLY treatment in the absence of biochar, with an effective concentration of 10% (EC10) of 5.23 mg/kg and an effective concentration of 20% (EC20) of 6.848 mg/kg. In the amended soil, overall, slight non-significant increases in biomass were recorded and no effective concentrations could be calculated due to the lack of significant biomass loss. The assessment of neurotoxicity via the activity of acetylcholine esterase (AChE) showed no change in AchE due to GLY in all the non-amended treatments. However, in the biochar-amended treatments, statistically high levels of AchE occurred (p < 0.05) even in the control (in the absence of GLY). The assessment of oxidative stress through catalase (CAT) activity, showed similar results with no significant effects of GLY alone on CAT activity, but rather dramatic increases in activity in the control and GLY treatments in the biochar-amended soil, with one significant increase in the 10% amended in 8 mg GLY/Kg (p < 0.05). Such significant increases in both AChE and CAT were only observed in soil amended with 10 and 15% biochar. Our findings show that although seemingly beneficial for whole body endpoints, biomarker responses indicate that a biochar amendment higher than 5% adds considerable additional stress to earthworms and should be avoided.
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Cong, Nguyen Van, Dinh Thai Danh, and Tran Sy Nam. "Effects of Chlorpyrifos Ethyl on Cholinesterase and Growth of Silver Barb (Barbonymus gonionotus)." Water 13, no. 20 (October 14, 2021): 2885. http://dx.doi.org/10.3390/w13202885.
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Chlorpyrifos ethyl is a popular insecticide widely used in agriculture within the Vietnamese Mekong delta, including for rice farming. Here, local farmers often apply pesticides at very high rates which leads to contamination of the surrounding environment. Silver barb (Barbonymus gonionotus) is a fish species indigenous to the delta, which resides in a variety of water bodies and is also commonly cultivated in rice–fish systems. As a result, this species is at high risk of exposure to chlorpyrifos ethyl. This study aims to determine the lethal concentration (LC50) of chlorpyrifos ethyl, as well as the effects of sub-lethal concentrations on the activity of cholinesterase and growth of Silver barb. Lethal concentration testing was conducted in a static non-renewed system. Three concentrations of chlorpyrifos ethyl (1%, 10% and 20% LC50-96 h) were conducted in triplicate to assess the effects of chlorpyrifos ethyl on the brain cholinesterase (ChE) of fingerling fish for 15 days, and on their growth for 60 days. Results showed that chlorpyrifos ethyl was highly toxic to fingerling Silver barb with a LC50-96 h of 0.119 ppm. The lowest observed effect concentration (LOEC) was 1%LC50-96 h for ChE and 10%LC50-96 h for growth. No observed effect concentration (NOEC) of chlorpyrifos ethyl for growth was 1%LC50-96 h. The result from this study suggests that ChE activity is significantly inhibited at environmentally realistic concentrations in the Vietnamese Mekong delta and can be used as a biomarker of pesticide exposure. Further study in the rice fields as well as in the canals or rivers is required.
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Gooneratne, S. R., C. T. Eason, C. J. Dickson, H. Fitzgerald, and G. Wright. "Persistence of sodium monofluoroacetate in rabbits and risk to non-target species." Human & Experimental Toxicology 14, no. 2 (February 1995): 212–16. http://dx.doi.org/10.1177/096032719501400210.
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1 Sodium monofluoroacetate (1080), a vertebrate pesti cide used in New Zealand, was administered orally to rabbits at two dose levels (sub-lethal and lethal) to determine how long 1080 would persist in plasma, liver, kidney, and muscle so that the risk of consump tion of meat from lethally or sub-lethally poisoned rab bits by non-target species could be assessed. 2 The plasma elimination half-life in rabbits receiving a sub-lethal dose was 1.1 h. Retention of 1080 in tissue was greater in rabbits dosed with a lethal dose than in those that received a sub-lethal dose. Irrespective of the dose level, concentration of 1080 in muscle, kidney, and liver was substantially lower than in the plasma. 3 Poisoning of dogs is possible because of their extreme susceptibility to 1080. Poisoning of birds is less likely. The risk of secondary poisoning is reduced as the con centration of 1080 declines in putrefying carcasses.
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Sysolyatina, M. A., and A. S. Olkova. "Potentiation of the toxic action of copper in the presence of lanthanum in bioassays for Daphnia magna Straus (Cladocera, Crustacea)." Povolzhskiy Journal of Ecology, no. 4 (December 23, 2022): 483–90. http://dx.doi.org/10.35885/1684-7318-2022-4-483-490.
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The available data on the combined action of rare earth elements and heavy metals are contradictory. Therefore, the goal of the presented work is relevant – to determine the effects of solutions of copper, lanthanum salts and their equimolar mixtures under controlled conditions for Daphnia magna Straus. It has been established that the death of D. magna over 50% in solutions containing Cu2+ is observed at a calculated concentration of 0.05 mg/L (0.0008 mmol/L), and a similar effect of solutions with La3+ occurs at a dose of 50 mg/L (0.36 mmol/L). The potentiation of the lethal effect of copper in the presence of lanthanum is shown. E.g., in solutions of mixtures of Cu and La salts, where the sum of metals is equimolar to non-lethal concentrations of Cu2+ (0.00016 and 0.0008 mmol/L), 100% death of D. magna is observed after 96 and 24 hours, respectively. Further, the potentiation effect was confirmed in bioassays evaluating the locomotor activity of D. magna. Solutions containing a mixture of “Cu2+ and La3+” (1:1) inhibit the motor activity of daphnia similarly to equimolar solutions containing only Cu2+. Thus, despite the significant difference between the effective lethal and non-lethal concentrations of Cu2+ and La3+ (by 1,000), it was found that under the combined action of equimolar doses of the metals, an increase in the toxicity of copper in the presence of lanthanum is observed.
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Takatsuka, V., D. G. C. Costa, N. Y. Oliveira, E. G. Sanches, and V. G. Azevedo. "Use of eugenol for anesthesia of lesser guitarfish Zapteryx brevirostris (Rhinobatidae)." Brazilian Journal of Biology 79, no. 3 (September 2019): 516–20. http://dx.doi.org/10.1590/1519-6984.186755.
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Abstract Anesthesia can be utilized as a non-lethal procedure to allow easy handling of teleosts and elasmobranchs in captivity or in the wild. For this, anesthetic protocols need to be established according to the species. The aim of this study was to determine the ideal concentration of eugenol for anesthesia of Zapteryx brevirostris. Four concentrations were tested: 21.25, 42.50, 85.00 and 170.00 mg L-1 (ratio of 1:5 with absolute ethanol). The perfect concentration of eugenol for this species was 85.0 mg L-1 , which enabled up to 300 seconds of work on the fish, without any response to handling.
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Lagas, Jurjen S., Jiri FP Wagenaar, Alwin DR Huitema, Michel JX Hillebrand, Cornelis HW Koks, Victor EA Gerdes, Desiderius PM Brandjes, and Jos H. Beijnen. "Lethal morphine intoxication in a patient with a sickle cell crisis and renal impairment: Case report and a review of the literature." Human & Experimental Toxicology 30, no. 9 (November 5, 2010): 1399–403. http://dx.doi.org/10.1177/0960327110388962.
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Morphine-6-glucuronide, the active metabolite of morphine, and to a lesser extent morphine itself are known to accumulate in patients with renal failure. A number of cases on non-lethal morphine toxicity in patients with renal impairment report high plasma concentrations of morphine-6-glucuronide, suggesting that this metabolite achieves sufficiently high brain concentrations to cause long-lasting respiratory depression, despite its poor central nervous system penetration. We report a lethal morphine intoxication in a 61-year-old man with sickle cell disease and renal impairment, and we measured concentrations of morphine and morphine-6-glucuronide in blood, brain and cerebrospinal fluid. There were no measurable concentrations of morphine-6-glucuronide in cerebrospinal fluid or brain tissue, despite high blood concentrations. In contrast, the relatively high morphine concentration in the brain suggests that morphine itself was responsible for the cardiorespiratory arrest in this patient. Given the fatal outcome, we recommend to avoid repeated or continuous morphine administration in renal failure.
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Sari, Fikret. "Lethal and sublethal effects of the pyrethroid insecticide tau-fluvalinate on the non-target organism Gammarus roeseli: A study of acute toxicity, genotoxicity and locomotor activity." Archives of Biological Sciences, no. 00 (2022): 33. http://dx.doi.org/10.2298/abs220930033s.
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Aquatic ecosystems are recipients of various contaminants including pesticides. For many years, pyrethroid insecticides (e.g., tau-fluvalinate) have been used extensively in agricultural activities to control pests. However, they can affect not only target organisms but also non-target organisms. This study was conducted to investigate the lethal and sublethal effects of tau-fluvalinate on the non-target organism Gammarus roeseli. To this end, acute toxicity of tau-fluvalinate was determined using a toxicity test with a 96-h exposure period, and the genotoxic effects of different sublethal concentrations on hemocytes of the test organism were assessed at 24-, 96-, and 240-h exposure periods using the comet assay. Alterations in locomotor activity of the test organism in response to exposure to sublethal concentrations were evaluated at 120- and 240-h periods. The 96-h median lethal concentration (LC50) was found to be 17.29 ?g/L, and tau-fluvalinate was observed to cause a significant increase in DNA damage and a significant reduction in locomotor activity at the tested sublethal concentrations (2.15, 4.30 and 8.60 ?g/L). The results of this study suggest that the long-term existence of tau-fluvalinate in aquatic environments at high concentrations is a noteworthy threat to non-target organisms and that its use in agricultural activities should be reconsidered.
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Kawano, Tomonori. "Use of Swimming Cells of Green Paramecia for Detection of Toxic Rare Earth Ions at Lethal and Sub-Lethal Concentration." Advanced Materials Research 875-877 (February 2014): 2229–37. http://dx.doi.org/10.4028/www.scientific.net/amr.875-877.2229.
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Paramecium bursaria is an unicellular organism that lives widely in fresh water environments such as rivers and ponds. Recent studies have suggested that in vivo cellular robotics using the cells of P. bursaria as micro-machines controllable under electrical and optical stimuli, has a variety of engineering applications such as transport of micro-sized particles in the capillary systems. The present study aimed to test if the swimming cells of P. bursaria, implementable in capillaries or on chips, are applicable for detection of metal ions. For model assays, rare earth elements (REEs) were chosen as target chemicals. In P. bursaria, LC50 values for REE ions ranged between 2.0 and 62.7 µM. Among them, Sc was shown to be most toxic. In addition to the lethal impacts of REE ions, most of REE ions at sub-lethal concentrations at around 10 - 30 µM, showed inhibitory action against the motility of the cells during the electrically forced motility known as galvanotaxisis. In conclusion, in the non-lethal ranges of REE concentration, swimming cells of P. bursaria report the presence of REE ions, by lowering the motility.
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Possenti, Cristina Daniela, Alexandra Bea Bentz, Andrea Romano, Marco Parolini, Manuela Caprioli, Diego Rubolini, Kristen Navara, and Nicola Saino. "Predation risk affects egg mass but not egg steroid hormone concentrations in yellow-legged gulls." Current Zoology 65, no. 4 (August 14, 2018): 401–8. http://dx.doi.org/10.1093/cz/zoy064.
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AbstractPredators have both direct, consumptive effects on their prey and non-lethal effects on physiology and behavior, including reproductive decisions, with cascading effects on prey ecology and evolution. Here, we experimentally tested such non-lethal effects of exposure to increased predation risk on clutch size, egg mass, and the concentration of yolk steroid hormones in the yellow-legged gull Larus michahellis. We simulated increased predation risk by displaying stuffed predators (adult fox Vulpes vulpes, and adult buzzard Buteo buteo) to breeding adults before egg laying. The concentration of corticosterone, which has been shown to increase under exposure to maternal predation risk in other species, and of testosterone did not differ between eggs from mothers exposed to the predators and eggs from control mothers (i.e., eggs exposed to a novel object of similar size and position to the stuffed predators). The concentration of the two hormones negatively covaried. Clutch size did not vary according to experimental treatment, whereas egg mass was markedly larger in clutches from nests exposed to predators than in clutches from control nests. By increasing egg mass, mothers may reduce the risk of cooling of the eggs when incubation is impeded by predators, boost energy reserves, reduce post-natal detectability caused by food solicitation, and/or enhance development at hatching, thus increasing the chances of offspring survival. In general, our results are inconsistent with most of the few previous studies on similar non-lethal predator effects and suggest that such effects may vary among species according to ecological conditions, social behavior, and developmental mode.
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Nafi’u, S. A., K. Suleiman, M. K. Ahmad, and M. Zakariyya. "Effect of Paraquat Herbicide on Oxidative Stress Biomaker Enzyme Activities in C. Gariepinus." Dutse Journal of Pure and Applied Sciences 7, no. 3b (January 6, 2022): 48–59. http://dx.doi.org/10.4314/dujopas.v7i3b.6.
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Toxicity assessment was conducted for 96hr exposure duration using synthetic herbicide (paraquat dichloride 276g/L) on Claris gariepinus with mean weight range of 27.2 - 29.7g and mean length 10.95 -15.5cm. They were exposed to varying herbicide concentrations of 0.0, 3.45, 6.90, 10.35 and 13.5mg/L with 5-levels exposure concentrations in a Completely Randomized Design (CRD). Liver, gills and kidney tissues were analyzed for oxidative stress enzymes activities using Solarbio science assay kit (BC1170, 0170 and 0020). Four days lethal concentration (LC50) value for 96hr was found to be 7.298mg/L. The treated fish displayed erratic swimming with irregular opercular movement, loss of reflex, mucus secretion and increased air gulping with the increasing concentration of the herbicide compared with the control fish. Antioxidant biomarkers activities revealed that Glutathione S-transferase (GST), catalase (CAT) and superoxide dismutase (SOD) activities increased significantly (P<0.05) in the gills, liver and kidney tissues at higher concentrations compared with control. It can be deduced that alterations in the oxidative stress enzyme activities in the exposed fish to paraquat exert toxic effect on the liver, gills and kidney tissues. It is therefore recommended that appropriate authorities should develop strategies on minimizing the indiscriminate use of synthetic herbicides due to their impact on aquatic biota such as fish in order to reduce its potential risk to other non-target organisms.
Keywords: Clarias gariepinus, Lethal concentration, Oxidative Stress enzymes, Paraquat, Toxicity assessment
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Escobar-Lux, Rosa H., and Ole B. Samuelsen. "The Acute and Delayed Mortality of the Northern Krill (Meganyctiphanes norvegica) When Exposed to Hydrogen Peroxide." Bulletin of Environmental Contamination and Toxicology 105, no. 5 (September 26, 2020): 705–10. http://dx.doi.org/10.1007/s00128-020-02996-6.
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Abstract Bath treatment pharmaceuticals used to control sea lice infestations in the salmonid industry, such as hydrogen peroxide (H2O2), are released directly into the environment where non-target organisms are at risk of exposure. The aim of this study was to determine the threshold concentrations for mortality of the Northern krill, Meganyctiphanes norvegica, a major component of the north Atlantic marine ecosystem. To assess the lethal effects of H2O2, we carried out a series of 1 h acute toxicity tests and assessed mortality through a 48 h post-exposure period. One-hour exposure to 170 mg/L, corresponding to 10% of the recommended H2O2 treatment, caused 100% mortality and a subsequent acute median-lethal concentration LC50 value of 32.5 mg/L. Increased mortality was observed with time in all exposed groups, resulting in successively lower LC50 values during the post-exposure period. The suggested H2O2 concentrations have the potential of causing negative effects to the Northern krill.
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Sarkar, Saurabh, Prem Rajak, and Sumedha Roy. "Toxicological Evaluation of a New Lepidopteran Insecticide, Flubendiamide, in Non-Target Drosophila melanogaster Meigen (Diptera: Drosophilidae)." Iranian Journal of Toxicology 12, no. 3 (May 1, 2018): 45–50. http://dx.doi.org/10.32598/ijt.12.3.477.1.
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Background: Flubendiamide, comparatively a new pesticide designed to eradicate lepidopteran insect pests is known to have low risk to birds, mammals, fish, algae, honey bees, non-target arthropods, earthworms, soil macro- and micro-organisms, non-target plants as well as sewage treatment organisms; however, the risk assessment for aquatic invertebrates from metabolite could not be finalized with available data. Methods: Different concentrations of flubendiamide (TATA TAKUMI®, Rallis, India) were introduced to larvae, pupae, and adult flies. A wide range of comparatively higher concentrations was selected for acute LC50 than chronic LC50 due to their exposure duration. Furthermore, relatively lower concentrations were introduced to larvae for assessment of emergence. Results: At chronic exposure, the effect-concentration relationship exhibited a linear response when adult emergence was considered in Drosophila melanogaster. When acute LC50 of flubendiamide in 3rd instar larvae was compared with the chronic LC50 then it was seen to be approximately 21 fold higher whereas chronic LC50 for adult flies was nearly 19 times less than the adult acute LC50. Similarly, adult emergence was seen to lower by 91.95% at 1500 µg/mL concentration. The chronic LC50 of the flubendiamide in Drosophila was approximately 170303 times more than the reported No Observed Effect Concentration (NOEC). Conclusion: Hence, the chemical, flubendiamide can induce its effects at very low concentration, far below the lethal ones. Thus, the study is of relevance for the non-target insects as well as the insect dependent organisms.
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Crespo-Lopez, María Elena, Allan Costa-Malaquias, Edivaldo H. C. Oliveira, Moysés S. Miranda, Gabriela P. F. Arrifano, José R. Souza-Monteiro, Fernanda Espirito-Santo Sagica, et al. "Is Low Non-Lethal Concentration of Methylmercury Really Safe? A Report on Genotoxicity with Delayed Cell Proliferation." PLOS ONE 11, no. 9 (September 13, 2016): e0162822. http://dx.doi.org/10.1371/journal.pone.0162822.
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Klevno, Vladimir А., and A. V. Maksimov. "ANALYSIS OF LETHAL OUTCOMES AMONG CHILDREN WITH ETHANOL IN BLOOD SAMPLES." Medical and Social Expert Evaluation and Rehabilitation 21, no. 1-2 (June 15, 2018): 70–72. http://dx.doi.org/10.18821/1560-9537-2018-21-1-70-72.
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Cases of consumption of alcoholic beverages by children and adolescents are rare. Children’s bodies are considered to be much less resistant to toxic effects of alcohol. However, there are described cases of the non-lethal ethanol poisoning in children when its blood concentration exceeded 5 g/L. The aim of the study. The forensic medical evaluation of the toxic action of ethanol in children depending on age, blood concentration of alcohol taking into account causes of death. Material. Data from statistical reporting, the Bureau of forensic medical examination for the Moscow region over the period of 2003-2017. Results. In lethal outcomes of children the prevalence rate of a positive result of the forensic chemical test of blood for the presence of ethyl alcohol was 1:6. Detected ethanol concentration in corpse blood would correspond to clinical manifestations of intoxication, from mild to severe. Conclusion. Children, whose blood alcohol content formally met the criterion of severe intoxication or alcohol poisoning, can take actions.
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AMAEZE, N. H., A. B. ONADEKO, and A. I. AGBOGBO. "ACUTE TOXICITY, OXIDATIVE STRESS AND DAMAGES TO GILLS OF CARDIOSOMA ARMATUM (RAINBOW CRAB) INDUCED BY EXPOSURE TO PESTICIDES (DICHLORVOS AND CYPERMETHRIN)." Nigerian Journal of Life Sciences (ISSN: 2276-7029) 5, no. 1 (March 25, 2022): 9–19. http://dx.doi.org/10.52417/njls.v5i1.203.
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The relative acute toxicity of Dichlorvos and Cypermethrin acting singly against Rainbow crab, Cardiosoma armatum was evaluated. The effects of sub lethal concentrations of the pesticides on the oxidative responses and histopathological effects in the gills of the crab were also investigated over a 30 days period. On the basis of 96 hrs LC50 value, Dichlorvos with 96 hr LC50 of 8.86 ?g/L was 2 times more toxic to the crabs than Cypermethrin with 96 hr LC50 of 17.80 ?g/L. The exposures to sub lethal concentrations (1/10th and 1/100th 96 hr LC50) of both pesticides each resulted in increase in the levels of lipid peroxidation product, malondialdehyde (MDA) in the gills compared to the control group at both day 15 and 30 of the bioassay . Super oxide dismutase (SOD) activity was inhibited by day 30 relative to control for both pesticides but the activities of Catalase (CAT) did not show a significant trend (P > 0.05). Exposure to sub lethal concentration (1/10th and 1/100th LC50) of both pesticides resulted in various histopathological effects such as curved filaments, fused filaments, epithelial lifting, congestion and odema. The damages to the gills were more severe in those exposed to Dichlorvous. The findings from this study indicates that both pesticides are potential threats to non- target rainbow crab populations and there is a risk of bioaccumulation and transport in the food chain under sub lethal exposures
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Cattò, Cristina, Luca De Vincenti, Francesca Cappitelli, Giusy D’Attoma, Maria Saponari, Federica Villa, and Fabio Forlani. "Non-Lethal Effects of N-Acetylcysteine on Xylella fastidiosa Strain De Donno Biofilm Formation and Detachment." Microorganisms 7, no. 12 (December 5, 2019): 656. http://dx.doi.org/10.3390/microorganisms7120656.
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This study investigated in-vitro the non-lethal effects of N-acetylcysteine (NAC) on Xylella fastidiosa subspecies pauca strain De Donno (Xf-DD) biofilm. This strain was isolated from the olive trees affected by the olive quick decline syndrome in southern Italy. Xf-DD was first exposed to non-lethal concentrations of NAC from 0.05 to 1000 µM. Cell surface adhesion was dramatically reduced at 500 µM NAC (−47%), hence, this concentration was selected for investigating the effects of pre-, post- and co-treatments on biofilm physiology and structural development, oxidative homeostasis, and biofilm detachment. Even though 500 µM NAC reduced bacterial attachment to surfaces, compared to the control samples, it promoted Xf-DD biofilm formation by increasing: (i) biofilm biomass by up to 78% in the co-treatment, (ii) matrix polysaccharides production by up to 72% in the pre-treatment, and (iii) reactive oxygen species levels by 3.5-fold in the co-treatment. Xf-DD biofilm detachment without and with NAC was also investigated. The NAC treatment did not increase biofilm detachment, compared to the control samples. All these findings suggested that, at 500 µM, NAC diversified the phenotypes in Xf-DD biofilm, promoting biofilm formation (hyper-biofilm-forming phenotype) and discouraging biofilm detachment (hyper-attachment phenotype), while increasing oxidative stress level in the biofilm.
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Carnohan, Lucas, Sang-Bin Lee, and Nan-Yao Su. "Concentration-Dependent Feeding Deterrence to 20-Hydroxyecdysone for Three Subterranean Termite Species (Blattodea: Rhinotermitidae)." Insects 12, no. 3 (March 4, 2021): 218. http://dx.doi.org/10.3390/insects12030218.
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Effective active ingredients in toxicant bait formulations must be non-deterrent to insect feeding behavior at lethal concentrations. This study evaluated feeding deterrence for Coptotermes formosanus Shiraki, C. gestroi (Wasmann), and Reticulitermes flavipes (Kollar) when provided access to cellulose impregnated with various concentrations of the insect molting hormone, 20-hydroxyecdysone (20E). Termites were exposed to 20E concentrations of 200, 500, 1000 and 2000 ppm and to noviflumuron at 5000 ppm in a 24 h choice-test, and the mass of substrate consumption from treated and untreated media pads was compared for each treatment. 20E feeding deterrence was detected at 500, 1000 and 2000 ppm for C. gestroi, and at 2000 ppm for C. formosanus. No significant differences in consumption of treated and untreated substrate was detected at any concentration for R. flavipes. Potential methods for reducing deterrence are discussed.
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Adomaitis, Mantas, and Grita Skujienė. "Lethal Doses of Saponins from Quillaja saponaria for Invasive Slug Arion vulgaris and Non-Target Organism Enchytraeus albidus (Olygochaeta: Enchytraeidae)." Insects 11, no. 11 (October 28, 2020): 738. http://dx.doi.org/10.3390/insects11110738.
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The slug, Arion vulgaris Moquin-Tandon, 1855, is a serious pest in agriculture and private gardens. White worm, Enchytraeus albidus Henle, 1837, is an important model of decomposer organism in the terrestrial ecosystem. Saponins, which are secondary metabolites of plants, have previously been shown to have some molluscicidal effect. We investigated which doses of saponins are lethal to the slug, A. vulgaris, and to the non-target organism, E. albidus. An aqueous solution with different concentrations of saponin extract from the bark of the soap tree, Quillaja saponaria Mol., was used in repeat treatments. Slugs were tested in filter paper contact tests as they are naturally exposed to soil contact while crawling. Worms were tested in soil contact tests as they live below ground. It was found that lethality of saponins depends on the slug age group and the environmental temperature. The median lethal concentration (LC50, at 15 °C) on adults was 68.5 g/L, and on juveniles, 96.9 g/L. The slugs were significantly more sensitive at 2 and −1 °C compared to 15 °C. The LC50 (at 6 ℃) on E. albidus was 2.7 g/L (or 0.5 g/kg dry weight of soil), far below those in A. vulgaris (at 15 ℃ and lower). The LC50 for worms at -1℃ was also significantly lower than at 6 ℃. Therefore, we can conclude: (1) that Q. saponaria saponins may be a successful slug control tool used during colder times of the year, but its concentration should be selected according to the age group of A. vulgaris; (2) this measure is more toxic than expected to white worms, which limits its use.
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Barros Gomes, Paulo Roberto, Marlucy Bezerra Oliveira, Dionney Andrade De Sousa, Jeremias Caetano Da Silva, Romer Pessôa Fernandes, Hilton Costa Louzeiro, Rayone Wesley Santos De Oliveira, Maria Do Livramento De Paula, Victor Elias Mouchrek Filho, and Maria Alves Fontenele. "Larvicidal activity, molluscicide and toxicity of the essential oil of Citrus limon peels against, respectively, Aedes aegypti, Biomphalaria glabrata and Artemia salina." Eclética Química Journal 44, no. 4 (October 1, 2019): 85. http://dx.doi.org/10.26850/1678-4618eqj.v44.4.2019.p85-95.
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In this present work, we tested the larvicidal activity, molluscicide and toxicity of the oil extracted from Citrus limon peels, respectively against third stage larvae of Aedes aegypti, snail Biomphalaria glabrata, and Artemia salina. For this, we extract the essential oil by hydrodistillation. Then, we identified and quantified the components by gas chromatography coupled to mass spectrometry (GC-MS). We tested the larvicidal and molluscicidal activity, respectively, using the method adopted by the Brazilian Ministry of Health and the World Health Organization. We calculated the lethal concentration (LC50) from the Probit method for the three biological activities with 95 %. The results of the chromatographic analysis showed that the oil has 58.81% of Limonene (major constituent) and 0.11% α-Mulene (minority component). The essential oil presented lethal concentration (LC50) for larvicidal activity, molluscicide and toxicity, respectively at 15.48, 13.05 and 743.35 mg∙L-1. Therefore, the essential oil is active against larvae of A. aegypti and snail B. glabrata and non-toxic against larvae of A. salina.
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Wiranatha, Jennifer, Robby Makimian, and Rita Dewi. "BIOINSECTICIDE AGAINST AEDES AEGYPTI MOSQUITOES DERIVED FROM LEMONGRASS (CYMBOPOGON CITRATUS) LEAVES ETHANOL EXTRACT." Damianus Journal of Medicine 20, no. 1 (May 31, 2021): 18–25. http://dx.doi.org/10.25170/djm.v20i1.1222.
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Introduction: Dengue hemorrhagic fever is one of the most common infectious diseases in Indonesia. The vector of this disease is Aedes aegypti (Ae. aegypti). Dengue hemorrhagic fever can be controlled by a few measures, one of them is using insecticide. However, frequent use of chemical insecticide could lead to resistance and is harmful to non-target organisms. One of the solutions for this problem is the use of bioinsecticide derived from lemongrass (Cymbopogon citratus or C. citratus) leaves extract.
Methods: The design of this study is true experimental post-test only control group. The population used are adult Ae. aegypti mosquitoes. For each experiment, 10 mosquitoes are required and given the extract of C. citratus in 2%, 10%, and 20% concentrations, and negative control respectively.The lethal effect of the extract is observed in 10, 30, 60 minutes and 6, 12, 18, 24 hours.
Results: There is a significant difference in the lethal effect of Ae. aegypti mosquitoes with variations in duration of exposure to the C. citratus leaves extract (p = 0.007), but no significant difference with variations in extract concentration given (p = 0.281).
Conclusion: C. citratus leaves extract has bioinsecticidal effect on Ae. aegypti mosquitoes. The optimal result of mosquito mortality is achieved by using the extract in 20% concentration with duration of 12 hours.
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SORRELLS, KENT M., and BARBARA LEONARD. "Mechanism of Acid Tolerance by a Yeast Isolated from Spoiled Ketchup." Journal of Food Protection 51, no. 6 (June 1, 1988): 489–90. http://dx.doi.org/10.4315/0362-028x-51.6.489.
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A yeast, isolated from spoiled ketchup, grew at a relatively high (0.8%) concentration of acetic acid. The addition of specific metabolic inhibitors in sub-lethal concentrations to acidified Potato Dextrose broth was used to study the mechanism of resistance of the yeast to acid. Growth in non-acidified medium was not affected by most inhibitors and to a limited extent by DNA and RNA inhibitors. Growth in the acidified medium was affected only slightly by the presence of inhibitors of protein (mitochondrial), DNA and RNA synthesis. 2,4-Dinitrophenol and D-cycloserine were the only inhibitors that inhibited growth in acidified media, suggesting acid tolerance involves an energy requiring system as well as cell walls, possibly transport.
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Dai, Changchun, Michele Ricupero, Zequn Wang, Nicolas Desneux, Antonio Biondi, and Yanhui Lu. "Transgenerational Effects of a Neonicotinoid and a Novel Sulfoximine Insecticide on the Harlequin Ladybird." Insects 12, no. 8 (July 28, 2021): 681. http://dx.doi.org/10.3390/insects12080681.
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The harlequin ladybird, Harmonia axyridis Pallas (Coleoptera: Coccinellidae), is a generalist predator and an effective biocontrol agent of various insect pests that has been exploited for the control of aphid pests in the greenhouse and field. However, insecticides are widely used to control aphid pests worldwide and the potential non-target effects of sulfoxaflor and imidacloprid for controlling aphid pests towards this biocontrol agent are little known. Although both sulfoxaflor and imidacloprid act on nicotinic acetylcholine receptors of insects, sulfoxaflor has a novel chemical structure compared with neonicotinoids. We assessed the lethal, sublethal and transgenerational effects of sulfoxaflor and imidacloprid on H. axyridis simultaneously exposed via ingestion of contaminated prey and via residual contact on the host plant at LC20 and LC50 doses estimated for the cotton aphid. Imidacloprid significantly reduced the survival of H. axyridis adults compared to sulfoxaflor at the same lethal concentration against cotton aphid. Both concentrations of imidacloprid and sulfoxaflor reduced the proportion of ovipositing females, and both concentrations of imidacloprid and sulfoxaflor, except LC20 dose of sulfoxaflor, reduced the fecundity and fertility of the parental generation. In the progeny of imidacloprid- and sulfoxaflor-exposed parents, both tested LC50 concentrations significantly decreased the juvenile survival rate, and both concentrations of imidacloprid and sulfoxaflor, except LC20 dose of sulfoxaflor, prolonged the development time. Our findings provide evidence of the negative influence of imidacloprid and sulfoxaflor at low lethal concentrations on the harlequin ladybird and on the progeny of exposed individuals, i.e., transgenerational effects. Hence, these findings stress the importance of optimizing the applications of imidacloprid and sulfoxaflor for the control of aphid pests, aiming at preserving the biocontrol services provided by H. axyridis throughout the integrated pest management approach.
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Mitropoulou, Gregoria, Antigoni Oreopoulou, Eleni Papavassilopoulou, Manolis Vamvakias, Panayiotis Panas, Stavros Fragias, and Yiannis Kourkoutas. "Origanum vulgare ssp. hirtum Essential Oil as a Natural Intrinsic Hurdle against Common Spoilage and Pathogenic Microbes of Concern in Tomato Juice." Applied Microbiology 1, no. 1 (February 20, 2021): 1–10. http://dx.doi.org/10.3390/applmicrobiol1010001.
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The aim of the present study was to assess the commercial potential of the Origanum vulgare ssp. hirtum essential oil (OEO) as a natural intrinsic hurdle against common spoilage and pathogenic microbes in tomato juice. The main volatile compounds of the OEO identified by gas chromatography mass spectrometry (GC/MS) analysis were thymol and carvacrol, accounting for approximately 48% and 27%, respectively. Its activity against common food spoilage and pathogenic microbes was confirmed and the minimum inhibitory concentration (MIC), non-inhibitory concentration (NIC), and minimum lethal concentration (MLC) values were determined. OEO effectiveness was further validated in commercial tomato juice. Supplementation of tomato juice with OEO at concentrations lower than the MIC (350 ppm) resulted in significant delay of food spoilage and extension of the product’s shelf-life, as well as in inhibition of Listeria monocytogenes, Clostridium difficile, Saccharomyces cerevisiae, and Aspergillus niger growth after deliberate inoculation in both room and refrigerated temperatures. In conclusion, the results suggested that OEO may be used as an efficient intrinsic inhibitor of food spoilage and growth of pathogenic microbes in tomato juice.
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Bauer, Gerhard, Jon Walker, Bruno Nervi, Julie Ritchey, Jackie Hughes, Bill Eades, Mark Bonyhadi, Jan Nolta, and John F. DiPersio. "Large Scale Ex Vivo GMP Expanded, Activated Human T Cells Consistently Induce Lethal GvHD in a Mouse Xenotransplant Model - A New Way To Study Treatments for Acute GvHD." Blood 106, no. 11 (November 16, 2005): 5242. http://dx.doi.org/10.1182/blood.v106.11.5242.5242.
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Abstract Donor lymphocyte infusions have become increasingly valuable for the treatment of hematologic diseases. In the past it has been reported that ex vivo activated and expanded human (hu) T lymphocytes, compared to fresh, non activated donor lymphocytes, have a markedly reduced ability to elicit normal immune functions in vivo. To overcome this problem, an improved method of ex vivo T cell activation and expansion and a model for in vivo testing of the function of cultured T cells is needed. We developed a more physiological, closed system GMP T cell stimulation protocol using clinical grade magnetic beads coated with CD3 and CD28 antibodies (Xcyte Therapies Inc., Seattle, WA), IL-2 at a low concentration added 24 hours after the initial culture setup and the new GMP grade serumfree Stemline T cell medium (Sigma, St. Louis, MO). This medium allowed the elimination of donor variability, which we experienced in T cell expansions with other serumfree media. Using our NOD SCID/β2m null mouse model of T cell expansion, we demonstrated that high concentrations of IL-2 (500 U/ml, as previously used in clinical T cell expansions) impair the in vivo functionality of expanded T cells. We therefore lowered the IL-2 concentration to 50 U/ml during culture. A 3 fold cell expansion after 4 days, and a 10 fold cell expansion after 8 days of culture could be observed. The CD4 and CD8 ratios were 1.6 ± 0.5 at the start, 1.7 ± 0.4 four days post activation and 1.1 ± 0.2 eight days post-activation, with viability greater than 95%. We conditioned NOD SCID/β2m null mice with 300 cGy of TBI and injected them retroorbitally with 1 x 107 non activated (n=8), 4 day activated (n=9), or 8 day activated hu T cells (n=5). Mice that received 4 or 8 day activated huT cells exhibited weight loss, high hu T cell engraftment, and high hu IFNγ serum levels. All these animals exhibited lethal GvHD with median survivals of 15 and 12 days, respectively. Activated cells outperformed non activated hu T cells in their GvHD potential since not all mice injected with non activated cells developed lethal GvHD. Interestingly, mice which received 4 day activated cells exhibited significantly increased percentages of hu T cells in the blood, spleen, liver and lung, as compared to animals that received non activated hu T cells. With non activated hu T cells, preferential expansion of hu CD4+ cells was seen in mouse organs; with activated hu T cells the CD4/CD8 input ratio was preserved. Although 8 day activated hu T cells also elicited lethal GvHD in all animals, we did not observe the same pattern of engraftment and organ infiltration as with 4 day activated cells. 4 day activated hu T cells produced significantly higher engraftment, hu IFNγ production, and destruction of mouse tissue compared to 8 day activated hu T cells. For the first time, these results demonstrate consistent lethal GvHD elicited in a mouse xenotransplant model by 107ex vivo activated, expanded hu T cells produced in a closed system, serumfree GMP manufacturing process outperforming non activated hu T cells.
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Gardoni, Davide, Elena Ficara, Pompilio Vergine, and Roberto Canziani. "A full-scale plug-flow reactor for biological sludge ozonation." Water Science and Technology 71, no. 4 (October 24, 2014): 560–65. http://dx.doi.org/10.2166/wst.2014.432.
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The reduction of biological excess sludge production using ozone is a well-known technology and is applied in several full-scale plants around the world. Nevertheless, optimisation of the process is not yet adequately documented in the literature. Operational parameters are usually chosen by assuming a direct proportionality between ozone dose and excess sludge reduction. This paper investigates the role of ozone concentration on process efficiency and demonstrates the (non-linear) inverse relationship between ozone dose and specific particulate chemical oxygen demand solubilisation in plug-flow contact reactors. The influence of total suspended solids concentration is also studied and described. No short-term lethal effects on heterotrophic biomass have been observed.
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Geraldes, Catarina, Cláudia Verdial, Eva Cunha, Virgílio Almeida, Luís Tavares, Manuela Oliveira, and Solange Gil. "Evaluation of a Biocide Used in the Biological Isolation and Containment Unit of a Veterinary Teaching Hospital." Antibiotics 10, no. 6 (May 27, 2021): 639. http://dx.doi.org/10.3390/antibiotics10060639.
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Hospital-acquired infections (HAIs) are a rising problem worldwide, and the best way of coping with them is through infection tracking and surveillance systems, combined with prevention strategies, namely efficient disinfection protocols, that employ various biocides. However, increasing reports about reductions in biocide susceptibility and the development of cross-resistance to antimicrobials emphasize the need for identifying the factors influencing biocide efficiency. In this study, 29 bacterial isolates (n = 3 E. coli, n = 2 Pseudomonas spp., n = 23 Enterococcus spp., and n = 1 Staphylococcus pseudintermedius), obtained from environmental samples collected from the Biological Isolation and Containment Unit (BICU), of the Veterinary Teaching Hospital of the Faculty of Veterinary Medicine, University of Lisbon, were tested in order to determine their antimicrobial susceptibility to various antibiotics. Thirteen of these isolates were further selected in order to determine their antimicrobial susceptibility to Virkon™ S, with and without the presence of organic matter. Afterward, seven of these isolates were incubated in the presence of sub-lethal concentrations of this formulation and, subsequently, new susceptibility profiles were determined. Fourteen of the 29 isolates (48.3%) were classified as multidrug resistant, all previously identified as enterococci. Concerning Virkon™ S’s susceptibility, the Minimal Bactericidal Concentration (MBC) of this biocide regarding all isolates was at least eight times lower than the concentration regularly used, when no organic matter was present. However, when organic matter was added, MBC values rose up to 23 times. After exposure to sub-lethal concentrations of Virkon™ S, four enterococci presented a phenotypical change regarding antimicrobial susceptibility towards gentamicin. Virkon™ S also resulted in higher MBC values, up to 1.5 times, in the presence of low concentrations of organic matter, but no rise in these values was observed in assays without interfering substance. Virkon™ S seemed to be an efficient formulation in eliminating all bacteria isolates isolated from the BICU. However, organic matter could represent a hindrance to this ability, which emphasizes the importance of sanitization before disinfection procedures. The changes seen in antimicrobial susceptibility could be explained by a general stress-induced response promoted by the sub-lethal levels of Virkon™ S. Additionally, when no organic matter was present, a decrease in susceptibility to this biocide seemed to be non-existent.
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Elebe, F. A. "Acute toxicity of Primextra Gold on freshwater fish, Clarias gariepinus (Burchell 1822)." Zoologist (The) 20, no. 1 (November 25, 2022): 101–7. http://dx.doi.org/10.4314/tzool.v20i1.13.
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The need to boost food productivity to meet the demands of the ever-increasing human population necessitates the frequent use of agrochemicals. Primextra Gold containing atrazine (329g/l) and S-metolachlor (400g/l) is commonly used in agriculture to control weeds, especially in rice paddies. Given that herbicides could harm non-target species like fish, this study examined the effects of Primextra Gold on the behaviour, haematology, blood biochemistry and kidney of Clarias gariepinus. Juvenile C. gariepinus mean weight (11.05±5.43g) and length (11.95±6.13cm) were exposed to lethal and sublethal concentrations of the herbicide. The toxicity assay showed that the median lethal concentration (LC50) was 3.63µg/l. The fish exposed to sublethal concentrations exhibited signs of asphyxiation. The white blood cell (9.4- 10.8×106), aspartate aminotransferase (40.01-60.01IU/l) and alanine aminotransferase (68.02-90.12IU/l) levels increased significantly (p<0.05) in the test group compared to the control. Contrarily, glucose (53.14-82.25mg/dl) and protein (3.12- 9.38mg/dl) were lower in the herbicide exposed group compared to the control (p <0.05). Kidney histopathology revealed focal loss of the renal tissue, mild intra renal haemorrhage, moderate focal loss of renal tissue and severe focal loss of renal tissue in the herbicide exposed fish. The findings of this study suggest that this herbicide is hazardous to aquatic life and has negative consequences for non-target species when used indiscriminately. It is recommended that the herbicide should be used with caution, especially near aquatic habitat to maintain good water quality and ensure sustenance of aquatic biodiversity.
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Swastika, Deby, Lenie Marlinae, and Laily Khairiyati. "Peran Ekstrak Daun Pepaya (Carica papaya Linn) terhadap Kematian Larva Nyamuk Aedes aegypti." Medical Laboratory Technology Journal 2, no. 2 (December 31, 2016): 66. http://dx.doi.org/10.31964/mltj.v2i2.98.
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<p style="text-align: justify;">Papaya plants contain many substances called papain, papain protease effect can kill larvae of Aedes aegypti. This study aimed to determine the effect of papaya leaves extracts (Carica papaya Linn) against Aedes aegypti larvae mortality. The research method was a quasi-experimental research design with Non-Equivalent Control Group. The concentration levels were 6.25%, 12.5%, 25%, 50%, 100%, and controls (CMC-Na) with 4 times replication. The Probit Analysis test results showed Lethal concentration (LC50) of papaya leaves extract (Carica papaya Linn) against Aedes aegypti larvae mortality was to 24.46% and the effective time is 22 hours. It is concluded that any different concentrations of papaya (Carica papaya Linn) leaves extract have effect on Aedes aegypti larvae mortality (p <0.05), the time depth of papaya leaves extract have effect on Aedes aegypti larvae mortality (p <0.05), the average number of Aedes aegypti larvae mortality for 24-hours in each concentration are concentration of 6.25% as much as 4.75 larvae, 12.5% concentration as much as 8 larvae, a concentration of 25% as much as 12 larvae, 50% concentration of 14.5 larvae, concentration 100% as much as 19 larvae and control as much as 1.25 larvae. The recommended suggestion is to conduct a phytochemical test to determine the active substances contained in papaya (Carica papaya Linn) leaves extract and to know the concentration of active substances in the extract.
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Rahman, Md Asfakur, Nirakar Sahoo, and Veerachandra Yemmireddy. "Analysis of Sanitizer Rotation on the Susceptibility, Biofilm Forming Ability and Caco-2 Cell Adhesion and Invasion of Listeria." Pathogens 11, no. 9 (August 24, 2022): 961. http://dx.doi.org/10.3390/pathogens11090961.
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The purpose of this study was to determine the effect of sanitizer use conditions on the susceptibility, biofilm forming ability and pathogenicity of Listeria monocytogenes. Two different strains of L. monocytogenes and a non-pathogenic L. innocua were exposed to sodium hypochlorite, benzalkonium chloride and peroxyacetic acid at different concentrations (4 to 512 ppm) and treatment times (30 s to 5 min), respectively. Under the tested conditions, no significant difference (p > 0.05) in reduction was observed among the three tested sanitizers. A reduction of 1 to 8 log CFU/mL was observed depending upon the sanitizer concentration and treatment times. The survived cells at the highest sublethal concentration and treatment time of a particular sanitizer upon re-exposure to the same or different sanitizer showed either no change or increased susceptibility when compared to parent strains. Upon repeated exposure to sanitizers at progressively increasing concentrations from 1 to 128 ppm, L. innocua was able to survive concentrations of up to 32 ppm benzalkonium chloride and 64 ppm peroxyacetic acid treatments, respectively. At the tested sub-lethal concentrations, no significant difference (p > 0.05) in biofilm formation was observed among the tested strains. Caco-2 interaction with L. innocua showed a reduction in invasion ability with sublethal concentrations of sanitizers.
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Mostafiz, Md Munir, Errol Hassan, Jae-Kyoung Shim, and Kyeong-Yeoll Lee. "Lethal and Sublethal Effects of Methyl Benzoate on the Predatory Bug Nesidiocoris tenuis." Insects 11, no. 6 (June 18, 2020): 377. http://dx.doi.org/10.3390/insects11060377.
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Benzoates (naturally occurring plant toxins) produce pesticidal effects on various pest insects and mites, but their effects on non-target insects are poorly understood. In this study, we evaluate the lethal and sublethal toxicity of methyl benzoate (MB) to adults of the generalist predatory bug Nesidiocoris tenuis (Reuter) (Hemiptera: Miridae). To assess lethal effects, N. tenuis was exposed to plant surfaces treated with 0.25%, 0.5% and 1% MB, as well as negative and positive controls (water and the neonicotinoid acetamiprid, respectively). Exposure to 1% MB resulted in the highest corrected mortality of 17.8% and 13.3% under laboratory and greenhouse conditions, respectively. Thus, 1% MB can be classified as harmless to N. tenuis according to the International Organization for Biological Control rating scheme. At the sublethal level, MB exposure did not significantly affect the consumption of eggs of the whitefly Bemisia tabaci by N. tenuis relative to negative control feeding rates. In contrast, acetamiprid at the manufacturer’s recommended concentration reduced N. tenuis feeding activity by 45.4%. Furthermore, in a Y-tube olfactometer assay, there were no significant differences between the olfactory responses of N. tenuis to MB concentrations and the negative control (water). This study therefore suggests that MB could be used safely for pest control in combination with N. tenuis.
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Tyagi, Rajeev. "Chronic effect due to changes in the contents of urea & creatinine in edible cat fish Channa punctatus (Bloch), under the stress of sub lethal concentration of methyl parathion – a pesticide." Environment Conservation Journal 12, no. 3 (December 22, 2011): 89–92. http://dx.doi.org/10.36953/ecj.2011.120317.
Full textAbstract:
The chronic effect of methyl parathion on cat fish Channa punctatus was observed by comparing the amount of urea & creatinine in the bio chemical blood plasma profile of a control group & a group exposed to methyl parathion pesticide, in sub lethal concentration. Lc50 value of fish was found 35µg/l. During the study it was found that the amount of urea in the experimental fish was increased upto alarming level, although the creatinine concentration increased gradually. As such fish food is consumed by the non target organisms & more specifically by the human being, its consumption usually results in the development of such symptoms, which are not mentioned in the routine literature.
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Delancey, Evan, Devin Allison, Hansa Raj KC, David F. Gilmore, Todd Fite, Alexei G. Basnakian, and Mohammad A. Alam. "Synthesis of 4,4′-(4-Formyl-1H-pyrazole-1,3-diyl)dibenzoic Acid Derivatives as Narrow Spectrum Antibiotics for the Potential Treatment of Acinetobacter Baumannii Infections." Antibiotics 9, no. 10 (September 28, 2020): 650. http://dx.doi.org/10.3390/antibiotics9100650.
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Acinetobacter baumannii has emerged as one of the most lethal drug-resistant bacteria in recent years. We report the synthesis and antimicrobial studies of 25 new pyrazole-derived hydrazones. Some of these molecules are potent and specific inhibitors of A. baumannii strains with a minimum inhibitory concentration (MIC) value as low as 0.78 µg/mL. These compounds are non-toxic to mammalian cell lines in in vitro studies. Furthermore, one of the potent molecules has been studied for possible in vivo toxicity in the mouse model and found to be non-toxic based on the effect on 14 physiological blood markers of organ injury.
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Nevárez-Prado, Lenin O., Nubia Amaya-Olivas, Alejandro Sustaita-Rodriguez, Jesús Rodríguez-Zapién, Erick Zúñiga-Rodríguez, María Cordova-Lozoya, Antonio García-Triana, Fabiola Sandoval-Salas, and León Hernández-Ochoa. "Chemical composition and toxicity of extracts of <i>Fouquieria splendens</i> against <i>Artemia salina</i>." AIMS Agriculture and Food 7, no. 2 (2022): 357–69. http://dx.doi.org/10.3934/agrfood.2022023.
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<abstract> <p>Ocotillo (<italic>Fouquieria splendens</italic>) has been used in Mexican traditional medicine for the treatment of blood circulation problems, swelling, and prostatic hyperplasia, among others. The objective of this study was to use different extraction methods (soxhlet, hydrodistillation and ultrasound) and solvents with different polarities (hexane, methyl chloride, ethyl acetate, acetone and methanol) to determine volatile compounds contained in ocotillo stems. Solvents used were water in hydrodistillation; hexane, methyl chloride, ethyl acetate, acetone, and methanol in soxhlet; and a solvent mixture of water acidified with methanol, acetone, and 1% acetic acid at a 50:35:15 ratio in the ultrasound method. The major components identified were bis (2-Ethylhexyl) phthalate, bis (2-Ethylhexyl) ester, butyl acetate, palmitic acid, and myristic acid. A toxicity assay on <italic>Artemia salina</italic> was conducted and the median lethal concentration was quantified. The bioassay showed that extracts isolated by non-polar solvents are extremely toxic because they were lethal at concentrations lower than 100 ppm, while polar extracts were innocuous. However, in polar extracts were found compounds that suggest their use in traditional medicine, the most relevant being 2-butoxyethanol, pentadecanol, and undecanal.</p> </abstract>
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Quisen, Regina, Yohana de Oliveira, Marcos Pileggi, Francine Cuquel, and Marguerite Quoirin. "Selective agent and A. tumefaciens overgrowth-control antibiotics in Eucalyptus camaldulensis Cotiledonary culture." Brazilian Archives of Biology and Technology 52, no. 6 (December 2009): 1485–92. http://dx.doi.org/10.1590/s1516-89132009000600020.
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The objectives of the present work were to establish the minimal lethal dose of the selective agent to determine the type and concentration of appropriate antibiotics for the elimination of Agrobacterium tumefaciens inoculated explants, without interfering with the regenerative potential of the E. camaldulensis cotyledonary explants. Non-transformed explants were cultivated in medium supplemented with kanamycin. The results showed that the antibiotic was suitable for the selection of transformed cells in the concentration of 9 mg L-1 as it inhibited the growth of non-transformed cells. Cotyledons infected with A. tumefaciens were cultivated in MS N/2 medium supplemented with BAP, ANA, Km and cefotaxime or AugmentinÒ . The highest average of regenerated shoots by explant (5,4) was observed in the presence of 300 mg L-1 of AugmentinÒ /15 days, followed by 150 mg L-1/15 days and 100 mg L-1/30 days.
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Li, Jiaqiao, Yameng Fan, Yan Zhang, Yamei Liu, Yan Yu, and Mao Ma. "Resveratrol Induces Autophagy and Apoptosis in Non-Small-Cell Lung Cancer Cells by Activating the NGFR-AMPK-mTOR Pathway." Nutrients 14, no. 12 (June 10, 2022): 2413. http://dx.doi.org/10.3390/nu14122413.
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Resveratrol (RSV) has been reported to induce autophagy and apoptosis in non-small-cell lung cancer A549 cells, and the nerve growth factor receptor (NGFR) regulates autophagy and apoptosis in many other cells. However, the effect of NGFR on autophagy and apoptosis induced by RSV in A549 cells remains unclear. Here, we found that RSV reduced the cell survival rate in time- and concentration-dependent manners, activating autophagy and apoptosis. Lethal autophagy was triggered by RSV higher than 55 μM. The relationship between autophagy and apoptosis depended on the type of autophagy. Specifically, mutual promotion was observed between apoptosis and lethal autophagy. Conversely, cytoprotective autophagy facilitated apoptosis but was unaffected by apoptosis. RSV enhanced NGFR by increasing mRNA expression and prolonging the lifespan of NGFR mRNA and proteins. RSV antagonized the enhanced autophagy and apoptosis caused by NGFR knockdown. As the downstream pathway of NGFR, AMPK-mTOR played a positive role in RSV-induced autophagy and apoptosis. Overall, RSV-induced autophagy and apoptosis in A549 cells are regulated by the NGFR-AMPK-mTOR signaling pathway.
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Adaku, Ngoka Chizoma, Leo C. Osuji, and Aduabobo I. Hart. "Lethal Effects Of Aqueous Methanol On Juvenile Tropical Freshwater Fish (Oreochromis niloticus)." International Journal of Research and Scientific Innovation 09, no. 10 (2022): 09–14. http://dx.doi.org/10.51244/ijrsi.2022.91001.
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In this study, juvenile tropical freshwater fish (Oreochromis niloticus) were exposed to different lethal concentrations (2.5 ml/L, 5.0ml/L, 10.0ml/L, 15.0ml/L, 20.0ml/L and 25.0ml/L respectively) of aqueous methanol and (0ml/L) which is a tank without the toxicant to serve as the control. The experiment was conducted using a static nonrenewable bioassay method. The fish were obtained from the African Regional Aquaculture Centre (ARAC), Aluu, Rivers State, Nigeria. The fishes were acclimated to an aquarium for 14 days. In order to determine the definitive test concentration, a range-finding test was conducted. The mortality, LC50s value, and the 95 per cent confidence intervals for test organisms were derived using standard procedures at 24hr, 48hr, 72hr, and 96hr respectively. There was a statistically (P<0.05) increase in the mortality rates as the concentration of the test chemical increased. The LC50 values at 24, 48, 72 and 96 hours recorded were 30.064ml/L, 26.562ml/L, 11.534ml/L, and 6.347ml/L respectively for the Chemical. The LC50 values showed that the chemical is toxic to this tropical freshwater fish. Hence, it is recommended that there should be a regulatory measure in the discharge of this chemical into the aquatic environment, to avert potential toxic effects that may result in the death of non-targeted aquatic organisms which is an edible meal for humans which in turn may affect human health.
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Quansah, Joycelyn, Himabindu Gazula, Da Liu, and Jinru Chen. "Effect of Pre-Exposure to Chlorine Dioxide on the Susceptibility of Fecal Coliforms to Antibiotics." Antibiotics 11, no. 2 (February 8, 2022): 215. http://dx.doi.org/10.3390/antibiotics11020215.
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Adaptive exposure to sub-lethal concentrations of sanitizers was previously reported to offer cross-protection to bacteria against antibiotics. This study was undertaken to determine whether the pre-exposure of fecal coliforms to suboptimal concentrations of a chemical sanitizer, chlorine dioxide (ClO2), alters their susceptibility to certain antibiotics. Fecal coliforms isolated from fresh fruit packing facilities (n = 12) were adapted in ½ or ¼ of the manufacturer-recommended concentration of ClO2. The susceptibility of the adapted and non-adapted cells to 13 different antibiotics was determined by observing the changes in their minimal inhibitory concentrations (MICs). The results showed that preadaptation to the suboptimal concentrations of ClO2, in general, either decreased or did not change the MICs of the antibiotics against selected fecal coliform isolates, with only two exceptions; preadaptation increased the MICs of kanamycin against two of the fecal coliform isolates, and of nalidixic acid against one of the fecal coliform isolates. The results suggest that the use of ClO2 has a relatively low risk of inducing the resistance of fecal coliforms to antibiotics.
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Zheng, Xin-Jun, Gui-Qing Xu, Yan Li, and Xue Wu. "Deepening Rooting Depths Improve Plant Water and Carbon Status of a Xeric Tree during Summer Drought." Forests 10, no. 7 (July 16, 2019): 592. http://dx.doi.org/10.3390/f10070592.
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Exploring the effects of drought on trees of different sizes is an important research topic because the size-dependent mortality pattern of the major dominant species significantly affects the structure and function of plant communities. Here we studied the physiological performance and non-structural carbohydrates (NSCs) dynamics of a small xeric tree species, Haloxylon ammodendron (C.A.Mey.) of different tree size with varying rooting depth, during summer drought. We measured predawn (Ψpd) and midday (Ψm) leaf water potential, osmotic potential at saturated turgor (π100), and turgor lost point (Ψtlp), stomatal conductance (gs) at noon, maximum photochemical efficiency of photosystem II (Fv/Fm) in the morning, and NSCs concentration, from June–September. Our results demonstrated that the summer drought reduces the overall performance of physiological traits of the small young trees more than the larger adult trees. Ψpd, gs and Fv/Fm dropped larger in the small-diameter groups than the larger diameter groups. Substantial osmotic adjustments were observed in small size individuals (with lower π100 and Ψtlp) to cope with summer drought. Furthermore, mean concentration of NSCs for the leaf and shoot were higher in September than in July in every basal stem diameter classes suggested the leaf and shoot acted as reserve for NSC. However the root NSCs concentrations within each basal stem diameter class exhibited less increase in September than in the July. At the same time, the small young tress had lower root NSCs concentrations than the larger adult tree in both July and September. The contrasting root NSC concentrations across the basal stem diameter classes indicated that the roots of smaller trees may be more vulnerable to carbon starvation under non-lethal summer drought. The significant positive relationship between rooting depth and physiological traits & root NSCs concentration emphasize the importance of rooting depth in determining the seasonal variation of water status, gas exchange and NSCs.
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Nambiar, Jagadeesh, and K. R. Ranjini. "EFFICACY OF CLERODENDRUM INFORTUNATUM AND CHROMOLAENA ODORATA ON CARBOHYDRATE CONTENT IN HAEMOLYMPH OF THE SIXTH INSTAR LARVAE OF ORTHAGA EXVINACEA HAMPSON." International Journal of Engineering Technologies and Management Research 5, no. 4 (February 26, 2020): 62–68. http://dx.doi.org/10.29121/ijetmr.v5.i4.2018.209.
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Orthaga exvinacea is one of the major pests of mango crop and the caterpillars defoliate the leaves and thereby reduce the crop yield. Use of synthetic insecticide is the quick method for the control this pest but its uncontrolled usage has resulted in serious lethal effects on non-target organisms and environmental pollution. Botanical insecticides are very effective, safe and ecologically acceptable. In the present study, the impact of methanolic leaf extracts of Clerodendrum infortunatum and Chromolaena odorata on carbohydrate concentration in the haemolymph of sixth instar larvae of O. exvinacea was studied under laboratory conditions. The different concentrations (1% to 5%) of each botanical treated mango leaves were fed to the sixth instar. After 48 hours, larvae were sacrificed to collect haemolymph and the quantitative estimation of carbohydrate has been done. The results showed that there was some noticeable decrease in the amount of carbohydrate in the treated larvae when compared to control. The decrease in level of carbohydrate concentration was correlated with the increase in concentration of botanicals. Among the botanicals tested C. odorata possessed more efficacy than that of C. infortunatum and this experiment reveals the potency of both botanicals to be used as natural biopesticides against this pest.
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Otabor, Itohan J., Emmanuel Okrikata, and Shalom Bulus. "COMPARATIVE LETHAL IMPACT OF GLYPHOSATE AND PARAQUAT ON AFRICAN MOUND-BUILDING TERMITES (Macrotermes bellicosus Smeathman)." FUDMA JOURNAL OF SCIENCES 6, no. 4 (August 23, 2022): 20–24. http://dx.doi.org/10.33003/fjs-2022-0604-1053.
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In Nigeria, glyphosate and paraquat are common herbicides employed for weed control because they are cost-effective in controlling weeds. It has been shown that, herbicides released into the environment can indirectly affect non-target species, often in harmful ways. We thus investigated the lethal effects of Force up® (glyphosate) and ParaQ® (paraquat) on workers of African mound-building termites (Macrotermes bellicosus Smeathman). The worker termites were treated with 30µl of glyphosate and paraquat at different concentrations viz; 25, 12.5, 6.25, 3.13 and 1.56 ml per 500 ml of water, while distilled water was used as control. Mortality of termites was recorded for 12 and 24 hrs after exposure. Data collected were subjected to variance analysis and probit regression. Results showed that glyphosate caused 48 - 88% mortality, while paraquat caused 36 - 96% mortality after 24 hrs exposure. The mortality was not dose-dependent as 12.5ml of glyphosate and paraquat exerted higher percentage of mortality than 25ml concentration. Conversely, the mortality increased after 24 hrs indicating time-dependent mortality. The toxicity index, i.e. (LC50 and LC90), was 16.82ml and 14.87ml for glyphosate and 2.63ml and 2.196ml for paraquat after 24 hrs of exposure. This apparently shows that paraquat is highly toxic to M. bellicosus at concentrations lower than the recommended rate. These findings calls for the re-evaluation of the use of paraquat-based herbicides in weed control as it negatively impacts termites populations which are key beneficial non-targets
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Al Bahi, Amgad A. H., and Warda S. Abdelgadir. "Toxicity of Dietary Hibiscus sabdariffa Linn (Malvaceae) Seed to Wistar Rats." International Journal of Applied Sciences and Biotechnology 1, no. 4 (December 21, 2013): 214–19. http://dx.doi.org/10.3126/ijasbt.v1i4.9103.
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In Sudan Hibiscus sabdariffa seeds after fermentation are commonly known as Furundu with high quality proteins consumed as substitute to meat mainly in the Western part of the country. The raw seed, 10, 15 and 20 % of the standard diet was fed to Wister rats for periods up to 12 weeks. These doses were found to be non-toxic but not lethal to the treated rats. There was no evidence of carcinogenic effect of Hibiscus sabdariffa seed on any of the vital organs, but the main features were depression of growth and diverse pathological changes on the liver, kidneys and intestines which were correlated with highly significant (P<0.001) elevation of serum Aspartate aminotransferase (AST), Alanine aminotransferase (ALT) and Alkaline phosphatase (ALP) activities and bilirubin (P<0.01) concentration in addition to a significant decrease (P<0.01) in cholesterol concentration. No change was observed in the total protein, globulin and urea concentrations of the test groups and albumin concentration in Groups 1 and 2 fed on diet containing 10 and 15% H. sabdarrifa seed. These findings were accompanied by leukocytosis and significantly lower red blood cells and haemoglobin concentration. Due to the elevated Mean corpuscular volume (MCV) and the normal values of the mean corpuscular Haemoglobin concentration (MCHC) in all the treatment groups the toxicity of H. Sabdariffa seed to Wistar rats resulted in macrocytic normochromic type of anaemia.DOI: http://dx.doi.org/10.3126/ijasbt.v1i4.9103 Int J Appl Sci Biotechnol, Vol. 1(4): 214-219
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Iserhienrhien, Lucky, Okolie Paulinus, and Etaware Mudiaga. "Antimicrobial Effect of Geophila obvallata (Schumach) Didr. Leaf Ectracts Against Pathogenic Microbes." Archives of Ecotoxicology 3, no. 4 (December 31, 2021): 103–9. http://dx.doi.org/10.36547/ae.2021.3.4.103-109.
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The increase in synthetic drug resistance by pathogenic microbes has led to the development of plant-based antimicrobial drugs that are more reliable and non-lethal to human health at increased dosage. The antibacterial and antifungal potential of Geophila obvallata extracts were tested on clinical isolates (Staphylococcus aureus, Klebsiella pneumoniae, Pseudomonas aeruginosa, Escherichia coli, Bacillus subtilis,Streptococcus pyogenes, Cryptococcus neoformans, Candida albicans and Aspergillus fumigatus) using standard techniques. The zones of inhibition were shown to increase with increasing concentrations of the extracts. Inhibition was higher in Gram positive bacteria (9.10 to 31.00mm in 40mg/mL concentration) than Gram negative bacteria (3.50 to 27.00mm in 40mg/mL concentration), while the fungal isolates had the least zones of inhibition (2.83 to 25.00mm in 40mg/ml concentration). The minimum inhibitory concentrations (MIC) were lowest in the methanol extract than aqueous extract. Simillarly, MIC for bacteria (Bacillus subtilis) and fungi (Aspergillus fumigatus) were 0.3 and 2.0mg/mL respectively. Methanol extract had higher antibacterial and antifungal effect than aqueous extract. Ciprofloxacin, used as control for bacteria had the highest inhibitory activity (33.67mm) when compared to that of the highest concentration of plant extracts administered. Also, ketoconazole gave the highest zones of inhibition (32.33mm) on the fungi isolates compared to those of the extracts. The performance of the methanol extract of 40mg/mL of Geophila obvallata in the inhibition of Bacillus subtilis was not significantly different from that of Ciprofloxacin. The findings in this study therefore validate the antimicrobial effect of Geophila obvallata leaf extracts as well as its possible application in medicine.