Academic literature on the topic 'DmMYB'
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Journal articles on the topic "DmMYB"
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Silva, Abdênego R., Fernanda V. Cabral, Camila R. Silva, Daniela F. T. Silva, Anderson Z. Freitas, Adriana Fontes, and Martha S. Ribeiro. "New Insights in Phenothiazinium-Mediated Photodynamic Inactivation of Candida Auris." Journal of Fungi 9, no. 7 (June 30, 2023): 717. http://dx.doi.org/10.3390/jof9070717.
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In recent years, Candida auris has emerged as a hazardous hospital-acquired pathogen. Its resistance to antifungal treatments makes it challenging, requiring new approaches to manage it effectively. Herein, we aimed to assess the impact of photodynamic inactivation mediated by methylene blue (MB-PDI) or 1,9-dimethyl MB (DMMB-PDI) combined with a red LED against C. auris. To evaluate the photoinactivation of yeasts, we quantified colony-forming units and monitored ROS production. To gain some insights into the differences between MB and DMMB, we assessed lipid peroxidation (LPO) and mitochondrial membrane potential (ΔΨm). After, we verified the effectiveness of DMMB against biofilms by measuring metabolic activity and biomass, and the structures were analyzed through scanning electron microscopy and optical coherence tomography. We also evaluated the cytotoxicity in mammalian cells. DMMB-PDI successfully eradicated C. auris yeasts at 3 μM regardless of the light dose. In contrast, MB (100 μM) killed cells only when exposed to the highest dose of light. DMMB-PDI promoted higher ROS, LPO and ΔΨm levels than those of MB. Furthermore, DMMB-PDI was able to inhibit biofilm formation and destroy mature biofilms, with no observed toxicity in fibroblasts. We conclude that DMMB-PDI holds great potential to combat the global threat posed by C. auris.
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Shtivelman, E., and J. M. Bishop. "The PVT gene frequently amplifies with MYC in tumor cells." Molecular and Cellular Biology 9, no. 3 (March 1989): 1148–54. http://dx.doi.org/10.1128/mcb.9.3.1148-1154.1989.
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The line of human colon carcinoma cells known as COLO320-DM contains an amplified and abnormal allele of the proto-oncogene MYC (DMMYC). Exon 1 and most of intron 1 of MYC have been displaced from DMMYC by a rearrangement of DNA. The RNA transcribed from DMMYC is a chimera that begins with an ectopic sequence of 176 nucleotides and then continues with exons 2 and 3 of MYC. The template for the ectopic sequence represents exon 1 of a gene known as PVT, which lies 50 kilobase pairs downstream of MYC. We encountered three abnormal configurations of MYC and PVT in the cell lines analyzed here: (i) amplification of the genes, accompanied by insertion of exon 1 and an undetermined additional portion of PVT within intron 1 of MYC to create DMMYC; (ii) selective deletion of exon 1 of PVT from amplified DNA that contains downstream portions of PVT and an intact allele of MYC; and (iii) coamplification of MYC and exon 1 of PVT, but not of downstream portions of PVT. We conclude that part or all of PVT is frequently amplified with MYC and that intron 1 of PVT represents a preferred boundary for amplification affecting MYC.
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Shtivelman, E., and J. M. Bishop. "The PVT gene frequently amplifies with MYC in tumor cells." Molecular and Cellular Biology 9, no. 3 (March 1989): 1148–54. http://dx.doi.org/10.1128/mcb.9.3.1148.
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The line of human colon carcinoma cells known as COLO320-DM contains an amplified and abnormal allele of the proto-oncogene MYC (DMMYC). Exon 1 and most of intron 1 of MYC have been displaced from DMMYC by a rearrangement of DNA. The RNA transcribed from DMMYC is a chimera that begins with an ectopic sequence of 176 nucleotides and then continues with exons 2 and 3 of MYC. The template for the ectopic sequence represents exon 1 of a gene known as PVT, which lies 50 kilobase pairs downstream of MYC. We encountered three abnormal configurations of MYC and PVT in the cell lines analyzed here: (i) amplification of the genes, accompanied by insertion of exon 1 and an undetermined additional portion of PVT within intron 1 of MYC to create DMMYC; (ii) selective deletion of exon 1 of PVT from amplified DNA that contains downstream portions of PVT and an intact allele of MYC; and (iii) coamplification of MYC and exon 1 of PVT, but not of downstream portions of PVT. We conclude that part or all of PVT is frequently amplified with MYC and that intron 1 of PVT represents a preferred boundary for amplification affecting MYC.
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Lee, Ah-Chiou, Fang-Shin Liao, and Hsiao-Feng Lo. "Temperature, Daylength, and Cultivar Interact to Affect the Growth and Yield of Lettuce Grown in High Tunnels in Subtropical Regions." HortScience 50, no. 10 (October 2015): 1412–18. http://dx.doi.org/10.21273/hortsci.50.10.1412.
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The production of lettuce, a cool-season leafy vegetable, in high tunnels the year around is a challenge for growers in subtropical regions. The aims of this research were to characterize the growth of locally grown lettuce cultivars, develop a new high-yielding cultivar by crossing romaine-type lettuce ‘Jhih Li Wo’ and Batavia type lettuce ‘Fu San’, and determine the relationships between climatic variables, temperature, and daylength, and days to harvest for maximum marketable yield (DMMY) in individual cultivars in high tunnels. Nine cultivars were grown in high tunnels in the spring and winter of 2008 and summer of 2009 to evaluate growth and maximum marketable yield (MMY), the latter being defined as the aboveground fresh weight of 5 ± 0.7 cm of plant stem. Romaine lettuce ‘Jhih Li Wo’ had a higher growth rate during the initiation of plant growth in the spring of 2008. ‘Jhih Li Wo’ and Batavia lettuce ‘Fu San’ also showed higher growth rate before harvest for the MMY (GRBHD) and exhibited higher MMY and DMMY than butterhead lettuce and leaf lettuce cultivars under summer and winter regimes. However, landraces of leaf lettuce are the main lettuces grown in high tunnels in summer rather than ‘Fu San’ and ‘Jhih Li Wo’ due to their needing fewer DMMY and having a more upright growth form. Among nine cultivars studied, Batavia lettuce ‘Fu San’, romaine lettuce ‘Jhih Li Wo’, and landrace ‘Bai Yeh Wo’ were found to be more adaptable to summer weather. Genotypes with superior growth and yield traits are essential for not only production but also breeding. A new cultivar, Taoyuan No.3, was developed by introducing the high growth rate trait during the initial period of plant growth from romaine lettuce ‘Jhih Li Wo’ into high-yielding Batavia lettuce ‘Fu San’. Another experiment was performed over eight successive seasons to analyze the correlation of temperature and daylength on DMMY for each cultivar using multiple regression analysis from 2008 to 2009. This showed that the proposed models expressed as coefficients of multiple determinants (R2) accounted for 72% to 91% of the total variation in DMMY in each cultivar. Temperature affected DMMY the most and the relative contributions of temperature and daylength to DMMY differed with cultivar. These results provide information about production practices for growers in subtropical regions to use in choosing suitable lettuce cultivars.
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Hosoi, Junichi, Masahiro Tanida, and Toru Tsuchiya. "Regulation of Plasma Substance P and Skin Mast Cells by Odorants." Journal of Cutaneous Medicine and Surgery 7, no. 4 (July 2003): 287–91. http://dx.doi.org/10.1007/s10227-002-0129-y.
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Background: Mast cells stimulate inflammation and itch sensation in the skin by releasing various mediators when they are activated. Stress exacerbates some skin diseases. We have reported that inhalation of certain odorants modulates immune reactions in the skin. Objective: The possible usage of odorants in the regulation of skin inflammation and itch sensation was to be examined. Methods: Female volunteers were subjected to interview stress with or without odorant inhalation. Mice were immobilized while inhaling odorants. Toluidene blue-stained sections were analyzed for activated mast cells. Plasma substance P level was determined by enzyme-linked immunoassay. Results: Interview stress induced plasma substance P only in volunteers who did not inhale odorants containing 2% 1,3-dimethoxy-5-methyl benzene (DMMB). Immobilization stress induced mast cell activation in mice and the activation was blocked by exposure to DMMB. Conclusions: Stress causes mast cell activation via an increase in substance P. The effect of stress is suppressed by inhalation of DMMB.
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Yeo, Tsin W., J. Brice Weinberg, Daniel A. Lampah, Enny Kenangalem, Peggy Bush, Youwei Chen, Richard N. Price, et al. "Glycocalyx Breakdown Is Associated With Severe Disease and Fatal Outcome in Plasmodium falciparum Malaria." Clinical Infectious Diseases 69, no. 10 (February 12, 2019): 1712–20. http://dx.doi.org/10.1093/cid/ciz038.
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AbstractBackgroundInteractions between the endothelium and infected erythrocytes play a major role in the pathogenesis of falciparum malaria, with microvascular dysfunction and parasite sequestration associated with worsening outcomes. The glycocalyx is a carbohydrate-rich layer that lines the endothelium, with multiple roles in vascular homeostasis. The role of the glycocalyx in falciparum malaria and the association with disease severity has not been investigated.MethodsWe prospectively enrolled Indonesian inpatients (aged ≥18 years) with severe (SM) or moderately severe (MSM) falciparum malaria, as defined by World Health Organization criteria, and healthy controls (HCs). On enrollment, blood and urine samples were collected concurrently with measurements of vascular nitric oxide (NO) bioavailability. Urine was assayed for glycocalyx breakdown products (glycosaminoglycans) using a dimethylmethylene blue (GAG-DMMB) and liquid chromatography-tandem mass spectrometry (GAG-MS) assay.ResultsA total of 129 patients (SM = 43, MSM = 57, HC=29) were recruited. GAG-DMMB and GAG-MS (g/mol creatinine) were increased in SM (mean, 95% confidence interval: 3.98, 2.44–5.53 and 6.82, 5.19–8.44) compared to MSM patients (1.78, 1.27–2.29 and 4.87, 4.27–5.46) and HCs (0.22, 0.06–0.37 and 1.24, 0.89–1.59; P < 0.001). In SM patients, GAG-DMMB and GAG-MS were increased in those with a fatal outcome (n = 3; median, interquartile range: 6.72, 3.80–27.87 and 12.15, 7.88–17.20) compared to survivors (n = 39; 3.10, 0.46–4.5 and 4.64, 2.02–15.20; P = 0.03). Glycocalyx degradation was significantly associated with parasite biomass in both MSM (r = 0.48, GAG-DMMB and r = 0.43, GAG-MS; P < 0.001) and SM patients (r = 0.47, P = 0.002 and r = 0.33, P = 0.04) and inversely associated with endothelial NO bioavailability.ConclusionsIncreased endothelial glycocalyx breakdown is associated with severe disease and a fatal outcome in adults with falciparum malaria.
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Zeng, Wen-Wen, Tsan-Chi Chen, Cheng-Huan Liu, Sheng-Yang Wang, Jei-Fu Shaw, and Yu-Ting Chen. "Identification and Isolation of an Intermediate Metabolite with Dual Antioxidant and Anti-Proliferative Activity Present in the Fungus Antrodia cinnamomea Cultured on an Alternative Medium with Cinnamomum kanehirai Leaf Extract." Plants 10, no. 4 (April 9, 2021): 737. http://dx.doi.org/10.3390/plants10040737.
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The fungus Antrodia cinnamomea has been used as a folk medicine for various diseases, especially cancer. When A. cinnamomea is cultured on the original host, an endangered woody plant Cinnamomum kanehirai Hayata, the fungus produces more active ingredients, but its growth is slow. Here, C. kanehirai leaf ethanol extract (KLEE) was used as a substitute for C. kanehirai wood to culture A. cinnamomea on solid medium to shorten the culture period and produce active metabolites en masse. The antioxidant activities of methanol extracts from A. cinnamomea cultured on KLEE (MEAC-KLEE) were evaluated by 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical-scavenging effect, reducing power, and ferrous ion-chelating effect, and the effective concentration (EC50) values were 0.27, 0.74, and 0.37 mg mL−1, respectively. MEAC-KLEE exhibited specific anti-proliferative activity against a non-small-cell lung cancer cell line (A549) by Annexin V assay. A secondary metabolite (2,4-dimethoxy-6-methylbenzene-1,3-diol, DMMB) present in the extract (MEAC-KLEE) was purified by high-performance liquid chromatography (HPLC) and identified by nuclear magnetic resonance (NMR) spectra. DMMB exhibited moderate antioxidant activity against DPPH radicals and reducing power, with EC50 values of 12.97 and 25.59 μg mL−1, respectively, and also induced apoptosis in A549 cells. Our results provide valuable insight into the development of DMMB for nutraceutical biotechnology.
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Jiang, Shijie, Pifeng Chen, Yang Zhan, and Chunyu Zhao. "Theoretical and Computational Analysis on the Melt Flow Behavior of Polylactic Acid in Material Extrusion Additive Manufacturing under Vibration Field." Applied Sciences 10, no. 11 (May 29, 2020): 3801. http://dx.doi.org/10.3390/app10113801.
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Material extrusion (ME), an extrusion-based rapid prototyping technique, has been extensively studied to manufacture final functional products, whose forming quality is significantly influenced by the melt flow behavior (MFB) inside the extrusion liquefier. Applied vibration has a great potential to improve the MFB, and thereby promote the forming quality of the built product. To reveal the mechanism, a dynamic model of the melt flow behavior (DMMFB) is established based on fluid dynamics, Tanner nonlinear constitutive equation and Newton’s power law equation. The MFB, i.e., pressure drop, shear stress and apparent viscosity, is investigated without and with different vibration applied. The corresponding finite element analysis (FEA) is then carried out. From the comparison between DMMFB and FEA results, it is concluded that the proposed model is reliable. When vibration is applied onto the extrusion liquefier, the time-domain MFB will change periodically. Its effective value decreases significantly, and further decreases with the increase of vibration frequency or amplitude. This paper provides the theoretical basis to improve the MFB by applied vibration, and thereby to enhance the forming quality of ME products.
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Lee, W. M., M. Schwab, D. Westaway, and H. E. Varmus. "Augmented expression of normal c-myc is sufficient for cotransformation of rat embryo cells with a mutant ras gene." Molecular and Cellular Biology 5, no. 12 (December 1985): 3345–56. http://dx.doi.org/10.1128/mcb.5.12.3345-3356.1985.
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We studied the effect of altered c-myc structure and expression upon the ability of c-myc to promote the transformation of normal rat embryo cells when it was supplemented by EJras (the mutant c-H-ras1 gene from EJ/T24 bladder carcinoma cells). We tested several c-myc alleles cloned from normal and tumor tissues of chicken and human origin and found that only LL4myc (derived from a bursal lymphoma in which an avian leukosis virus long terminal repeat resides within the first c-myc intron in the same transcriptional orientation) had cotransforming activity. No activity was observed with normal chicken and human c-myc alleles, two other bursal lymphoma c-myc alleles (LL3myc and LL6myc), and two human c-myc genes (HSRmyc and DMmyc) from human neuroectodermal tumor cell line COLO320, in which c-myc is amplified. Some of these inactive alleles had the following alterations that are frequently found in tumor-derived c-myc: point mutations affecting the encoded protein (LL3myc); a truncated structure with loss of the first, noncoding exon (LL3myc and DMmyc); and proviral integration within or near the myc locus (LL3myc and LL6myc). The following two experimental approaches indicated that cotransforming activity was directly related to the transcriptional activity of the alleles in cultured rat cells: when cotransfected into Rat-2 cells, LL4myc was more highly expressed than the other (inactive) alleles; and augmented expression of HSRmyc, DMmyc, or normal human or normal chicken c-myc placed under the transcriptional control of retroviral long terminal repeats or increased expression of normal human c-myc under the influence of a retroviral enhancer element was accompanied by cotransformation activity. We concluded that augmented expression of even a normal c-myc gene is sufficient for cotransforming activity and that additional structural alterations frequently found in tumor-derived alleles are neither necessary nor sufficient for the gene to acquire rat embryo cell cotransforming properties.
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Lee, W. M., M. Schwab, D. Westaway, and H. E. Varmus. "Augmented expression of normal c-myc is sufficient for cotransformation of rat embryo cells with a mutant ras gene." Molecular and Cellular Biology 5, no. 12 (December 1985): 3345–56. http://dx.doi.org/10.1128/mcb.5.12.3345.
Full textAbstract:
We studied the effect of altered c-myc structure and expression upon the ability of c-myc to promote the transformation of normal rat embryo cells when it was supplemented by EJras (the mutant c-H-ras1 gene from EJ/T24 bladder carcinoma cells). We tested several c-myc alleles cloned from normal and tumor tissues of chicken and human origin and found that only LL4myc (derived from a bursal lymphoma in which an avian leukosis virus long terminal repeat resides within the first c-myc intron in the same transcriptional orientation) had cotransforming activity. No activity was observed with normal chicken and human c-myc alleles, two other bursal lymphoma c-myc alleles (LL3myc and LL6myc), and two human c-myc genes (HSRmyc and DMmyc) from human neuroectodermal tumor cell line COLO320, in which c-myc is amplified. Some of these inactive alleles had the following alterations that are frequently found in tumor-derived c-myc: point mutations affecting the encoded protein (LL3myc); a truncated structure with loss of the first, noncoding exon (LL3myc and DMmyc); and proviral integration within or near the myc locus (LL3myc and LL6myc). The following two experimental approaches indicated that cotransforming activity was directly related to the transcriptional activity of the alleles in cultured rat cells: when cotransfected into Rat-2 cells, LL4myc was more highly expressed than the other (inactive) alleles; and augmented expression of HSRmyc, DMmyc, or normal human or normal chicken c-myc placed under the transcriptional control of retroviral long terminal repeats or increased expression of normal human c-myc under the influence of a retroviral enhancer element was accompanied by cotransformation activity. We concluded that augmented expression of even a normal c-myc gene is sufficient for cotransforming activity and that additional structural alterations frequently found in tumor-derived alleles are neither necessary nor sufficient for the gene to acquire rat embryo cell cotransforming properties.
Dissertations / Theses on the topic "DmMYB"
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Rajvanshi, Pradumn K. "Molecular and biochemical studies on components of transcription regulation, tropane alkaloid biosynthesis and signal transduction in the medicinal plant Datura metel L." Thesis, 2021. https://etd.iisc.ac.in/handle/2005/5552.
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Tropane alkaloids (TA) are among the oldest medicines known to humankind as they possess hallucinogenic and poisonous properties. Datura metel, an herbaceous plant, belongs to the family Solanaceae whose members are well known to produce tropane alkaloids. The isolation of the key biosynthetic enzymes, transcription factors, and protein kinases and their corresponding genes, is important in understanding TA biosynthesis and in developing metabolic engineering approaches to enhance the amount of tropane alkaloids in plants. Putrescine-N- methyltransferase (PMT; EC 2.1.1.53) is the first enzyme in the tropane alkaloid and nicotine biosynthetic pathway and it catalyzes the S-adenosylmethionine (SAM) dependent N-methylation of putrescine to methyl-putrescine. In the present study, Datura metel putrescine methyltransferase (DmPMT) protein has been biochemically and biophysically characterized. The initial rate kinetic study for DmPMT showed the Vmax 24.47 nKat/mg, Km for Putrescine 255.5 M and Km for SAM were 128.2M. The ordered Bi Bi kinetic mechanism best describes the N-methyl-transferase reaction catalyzed by DmPMT. Upon structural analysis of this N-terminus β-sheet and putrescine binding pocket, we could predict that the interaction of Trp-64 of N-term to the amino group of Putrescine through Cation-π interaction. Most probably, this interaction is crucial for keeping Putrescine in better orientation towards SAM.
Here we report the isolation of transcription factor DORA and DmMYB from Datura metel. q-RTPCR showed that expression of the DORA gene was strongly induced by treatment with fungal extract and moderately induced by methyl jasmonate plus wounding treatments. The Gel mobility shift assay showed that the recombinant DORA protein could bind specifically to GCC box, a cis-acting element present in the promoter regions of several target genes regulated by AP2 domain-containing transcription factor. DmMYB also exhibited sequence-specific DNA-binding. The binding constant for DmMYB-DNA interaction (Kd) was calculated to be 8.1*10-9 M, and the stoichiometry of the interaction was 1:1. 3D homology model of the DmMYB-DNA complex was constructed, confirming the role of TRP-17 and TRP-89 in complex formation. Further, our model highlighted a possible functional role of DmMYB-Mg2+ binding.
In the present study, we have isolated a full-length CDPK cDNA, DmCDPK1 (GenBank accession number ABY28389), from Datura metel by RT-PCR and rapid amplification of cDNA ends (RACE) methods. The recombinant DmCDPK1 with His-tag was heterologous expressed in E. coli and purified using Ni-NTA affinity chromatography. Biochemical analyses showed that both activities of autophosphorylation and phosphorylation of histone III-S substrate by DmCDPK1 protein are dependent on calcium. The kinase activity of the recombinant enzyme was calmodulin independent and sensitive to CaM antagonists, W7, and calmidazolium.CSIR, IISC, ICMR, DST
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Raja, Tehmeena I., Seyed A. Khaghani, M. S. Zafar, Z. Khurshid, M. Mozafari, Mansour Youseffi, and Farshid Sefat. "Effect of TGF-β1 on water retention properties of healthy and osteoarthritic chondrocytes." 2018. http://hdl.handle.net/10454/16988.
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YesArticular cartilage, a connective tissue, contains chondrocytes and glycosaminoglycans (GAGs) which aid in water retention, providing the tissue with its magnificent ability to prevent friction, withstand loads and absorb compressive shocks however, cartilage, does not have the ability to regenerate and repair. Osteoarthritis (OA) is a progressive degenerative disease, which includes reduction of cartilage thickness between two bones in a joint, causing painful bone-to-bone contact. OA affects over 8 million people in the UK alone. , and as the primary causes are unknown, available treatments including surgical and non-surgical techniques which only reduce the symptoms created by the disorder instead of providing a cure. This project focused on utilizing TGF-β1, a cytokine found in elevated amounts in healthy cartilage when compared to degraded cartilage, in order to observe the effects of the growth factor on both healthy and osteoarthritic chondrocytes. The healthy and the osteoarthritic chondrocytes were cultured in two different media (DMEM with and without TGF- β1) before utilizing the SpectraMax M2/M2e plate reader to observe and analyze the effect of TGF-β1 on water retention properties of cells. This has been achieved by quantifying the GAG content using DMMB dye. Results showed that although TGF-β1 did displayed an increase in glycosaminoglycan synthesis, the statistical increase was not vast enough for the alternative hypothesis to be accepted; further experimentation with TGF-β1, alongside other cytokines within the growth factor family is needed to perceive the true influence of the growth factor on un cured degenerative diseases. It was concluded that both the healthy and osteoarthritic cells treated with TGF-β1 absorbed considerably more DMMB in comparison to the cells, suggesting that TGF-β1 indeed works to aid in water retention. TGF-β1 is a key factor to be exploited when constructing treatments for osteoarthritis
Book chapters on the topic "DmMYB"
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Ladner, Yann D., Mauro Alini, and Angela R. Armiento. "The Dimethylmethylene Blue Assay (DMMB) for the Quantification of Sulfated Glycosaminoglycans." In Cartilage Tissue Engineering, 115–21. New York, NY: Springer US, 2022. http://dx.doi.org/10.1007/978-1-0716-2839-3_9.
Full textConference papers on the topic "DmMYB"
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Alves de Brito Júnior, Anildo, Laís França Figueirêdo, Marcus Vinicius Rocha Silva Leal, Guilherme Alves Aguiar, Antônio Luiz Barbosa Pinheiro, and Juliana Monteiro Azevedo. "Inativação fotodinâmica de Staphylococcus aureus mediada por nano concentração de azul de dimetil-metileno." In Congresso Brasileiro de Inovação em Microbiologia. Congresse.me, 2022. http://dx.doi.org/10.54265/sfdx4492.
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Eixo Temático: Biotecnologia Introdução:A terapia fotodinâmica mostra um potente efeito microbicida na presença de um corante fotossensibilizador associado a uma fonte de luz em um comprimento de onda específico. O corante fotossensibilizador acumula-se no microorganismo, onde vai absorver fótons da fonte de luz com energia suficiente para ficarem em seu estado excitado eletrônico, e então poderem reagir com um substrato local para formar radicais citotóxicos ou reagir diretamente com o oxigênio molecular para produzir oxigênio singleto e espécies reativas de oxigênio. Estes radicais livres causam danos celulares e a morte do microorganismo. Portanto, a inativação fotodinâmica é um método alternativo promissor para o tratamento de doenças infecciosas. Objetivo(s): O objetivo deste estudo foi avaliar os efeitos de inativação fotodinâmica em Staphylococcus aureus usando o corante azul de Taylor (DMMB) associado ao LED vermelho (λ 630 ηm ± 10 ηm, CW, 125 mW, 12 J/cm ², 192 s). Métodos: Foram realizados quatro grupos experimentais, Controle, LED, DMMB, DMMB + LED, após a realização da terapia fotodinâmica as amostras foram incubadas por 24 horas e o número de bactérias sobreviventes de cada tratamento foi determinado por contagem das unidades formadoras de colônia (UFC/mL). O logaritmo (UFC/mL log) foi calculado. Todas as experiências foram realizadas em triplicata. As análises estatísticas foram realizadas utilizando-se o software GraphPad Prism (versão 6.0) e analisados por meio de testes ANOVA unidirecional, comparações múltiplas de Tukey e regressão não linear. Os valores de p<0,05 foram considerados estatisticamente significantes. Resultados: De acordo com os resultados, no grupo LED, onde a fonte de luz foi utilizada isoladamente, é demonstrado um aumento significativo (p=0,0001) na carga microbiana d e S aureus quando comparado ao grupo Controle. A ação do fotossensibilizador utilizado sozinho, no grupo DMMB não foi capaz de demonstrar redução significante da população de S aureus quando comparado ao grupo Controle, porém quando o DMMB é associado ao LED, no grupo da inativação fotodinâmica (DMMB + LED) é observado uma redução significativa da carga microbiana (p<0,0001) quando comparado ao grupo Controle, com uma redução percentual de 99,97%. Conclusão: Em conclusão, estes resultados demonstraram que a inativação fotodinâmica fornece uma opção terapêutica alternativa para combater infecções estafilocócicas. Ressalta-se ainda que o protocolo utilizado na presente pesquisa foi de uma única aplicação, sendo possível repeti-la alcançando resultados ainda melhores na redução da carga microbiana. Resumo - sem apresentação (com DOI). PALAVRAS-CHAVE: DMMB, LED, Staphylococcus aureus, Terapia fotodinâmica antimicrobiana
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Pinheiro, Antônio Luiz B., Fernando José P. Sampaio, Darcy Santos de Almeida, Pedro Jorge L. Crugeira, Susana Carla P. S. de Oliveira, Juliana S. C. Monteiro, Sandra Regina C. A. Fagnani, Iago P. F. Nunes, Luiz Guilherme P. Soares, and Paulo Fernando Almeida. "Nanoconcentrations of of 1,9-dimethylmethylene blue (DMMB) associated to laser, LED or polarized light are highly effective on AmPDT carried out in aerobes and aerotolerant anaerobes Gram-positive bacteria." In Mechanisms of Photobiomodulation Therapy XV, edited by Michael R. Hamblin, James D. Carroll, and Praveen Arany. SPIE, 2020. http://dx.doi.org/10.1117/12.2543732.
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