RESUMO
Viruses target mitochondria to promote their replication, and infection-induced stress during the progression of infection leads to the regulation of antiviral defenses and mitochondrial metabolism which are opposed by counteracting viral factors. The precise structural and functional changes that underlie how mitochondria react to the infection remain largely unclear. Here we show extensive transcriptional remodeling of protein-encoding host genes involved in the respiratory chain, apoptosis, and structural organization of mitochondria as herpes simplex virus type 1 lytic infection proceeds from early to late stages of infection. High-resolution microscopy and interaction analyses unveiled infection-induced emergence of rough, thin, and elongated mitochondria relocalized to the perinuclear area, a significant increase in the number and clustering of endoplasmic reticulum-mitochondria contact sites, and thickening and shortening of mitochondrial cristae. Finally, metabolic analyses demonstrated that reactivation of ATP production is accompanied by increased mitochondrial Ca2+ content and proton leakage as the infection proceeds. Overall, the significant structural and functional changes in the mitochondria triggered by the viral invasion are tightly connected to the progression of the virus infection.
Assuntos
Herpes Simples , Herpesvirus Humano 1 , Mitocôndrias , Mitocôndrias/metabolismo , Herpesvirus Humano 1/fisiologia , Herpesvirus Humano 1/metabolismo , Humanos , Herpes Simples/metabolismo , Herpes Simples/virologia , Herpes Simples/patologia , Animais , Infecções por Herpesviridae/metabolismo , Infecções por Herpesviridae/virologia , Infecções por Herpesviridae/patologia , Progressão da Doença , Chlorocebus aethiopsRESUMO
Herpes simplex virus capsids are assembled and packaged in the nucleus and move by diffusion through the nucleoplasm to the nuclear envelope for egress. Analyzing their motion provides conclusions not only on capsid transport but also on the properties of the nuclear environment during infection. We utilized live-cell imaging and single-particle tracking to characterize capsid motion relative to the host chromatin. The data indicate that as the chromatin was marginalized toward the nuclear envelope it presented a restrictive barrier to the capsids. However, later in infection this barrier became more permissive and the probability of capsids to enter the chromatin increased. Thus, although chromatin marginalization initially restricted capsid transport to the nuclear envelope, a structural reorganization of the chromatin counteracted that to promote capsid transport later. Analyses of capsid motion revealed that it was subdiffusive, and that the diffusion coefficients were lower in the chromatin than in regions lacking chromatin. In addition, the diffusion coefficient in both regions increased during infection. Throughout the infection, the capsids were never enriched at the nuclear envelope, which suggests that instead of nuclear export the transport through the chromatin is the rate-limiting step for the nuclear egress of capsids. This provides motivation for further studies by validating the importance of intranuclear transport to the life cycle of HSV-1.
Assuntos
Transporte Biológico Ativo/fisiologia , Capsídeo/metabolismo , Cromatina/metabolismo , Membrana Nuclear/metabolismo , Simplexvirus/metabolismo , Animais , Chlorocebus aethiops , Herpes Simples , Células Vero , Replicação Viral/fisiologiaRESUMO
DNA damage in all living cells is repaired with very high efficiency and nucleic acid binding proteins play crucial roles in repair associated processes. Translin is one such evolutionarily conserved nucleic acid interacting protein speculated to be a part of the DNA repair protein network. It is also involved in activation of RNA-induced silencing complex (RISC) along with Translin-associated factor X (TRAX) as the C3PO (component 3 promoter of RISC) complex. In the present work, we characterized ten clinically relevant variants of the human Translin protein using bioinformatic, biochemical, and biophysical tools. Bioinformatic studies using DynaMut revealed 9 out of the 10 selected mutations the Translin protein. Further analysis revealed that some mutations lead to changes in interactions with neighbouring residues in the protein structure. Using site directed mutagenesis, the point substitution variants were generated, corresponding proteins were overexpressed and purified using Ni-NTA affinity chromatography. Purified proteins form octamers similar to wild type (WT) Translin, as observed using native polyacrylamide gel electrophoresis (PAGE), gel filtration, and dynamic light-scattering (DLS) analysis. These octamers are functional and bind to single-stranded DNA (ssDNA) as well as single-stranded RNA (ssRNA) substrates. The mutant Translin proteins interact with wild type TRAX and form corresponding C3PO complexes. The C3PO complexes formed by all Translin variants with TRAX are functional in-vitro and show endoribonuclease activity. However, significant differences were observed in the extent of RNase activity in vitro. In conclusion, the clinically relevant mutations in Translin protein analysed by us exert their effect by modulating the RNase activity of the protein without altering its DNA-dependant function.
Assuntos
Ácidos Nucleicos , RNA , Humanos , RNA/metabolismo , Ácidos Nucleicos/metabolismo , DNA/metabolismo , Mutação , RibonucleasesRESUMO
Sertoli cells (Sc) are the sole target of follicle-stimulating hormone (FSH) in the testis and attain functional maturation post-birth to significantly augment germ cell (Gc) division and differentiation at puberty. Despite having an operational microRNA (miRNA) machinery, limited information is available on miRNA-mediated regulation of Sc maturation and male fertility. We have shown before that miR-92a-3p levels decline in pubertal rat Sc. In response to FSH treatment, the expressions of FSH Receptor, Claudin11 and Klf4 were found to be elevated in pubertal rat Sc coinciding with our finding of FSH-induced decline in miR-92a-3p levels. To investigate the association of miR-92a-3p and spermatogenesis, we generated transgenic mice where such pubertal decline of miR-92a-3p was prevented by its overexpression in pubertal Sc under proximal Rhox5 promoter, which is known to be activated specifically at puberty, in Sc. Our in vivo observations provided substantial evidence that FSH-induced decline in miR-92a-3p expression during Sc maturation acts as an essential prerequisite for the pubertal onset of spermatogenesis. Elevated expression of miR-92a-3p in post-pubertal testes results into functionally compromised Sc, leading to impairment of the blood-testis barrier formation and apoptosis of pre-meiotic Gc, ultimately culminating into infertility. Collectively, our data suggest that regulation of miR-92a-3p expression is crucial for Sc-mediated induction of active spermatogenesis at puberty and regulation of male fertility.
Assuntos
Diferenciação Celular , Fertilidade , Hormônio Foliculoestimulante/farmacologia , Células Germinativas/citologia , MicroRNAs/genética , Células de Sertoli/citologia , Testículo/citologia , Animais , Feminino , Células Germinativas/efeitos dos fármacos , Células Germinativas/metabolismo , Hormônios/farmacologia , Masculino , Camundongos , Camundongos Transgênicos , Ratos , Ratos Wistar , Receptores do FSH/genética , Receptores do FSH/metabolismo , Células de Sertoli/efeitos dos fármacos , Células de Sertoli/metabolismo , Maturidade Sexual , Espermatogênese , Testículo/efeitos dos fármacos , Testículo/metabolismoRESUMO
The soils of Lakshadweep Islands are formed as a result of the fragmentation of coral limestone, that is carbonate-rich, with neutral pH, but poor in plant nutrients. Coconut palm (Cocos nucifera L.) is the main crop cultivated, supporting the life and livelihood of the islanders. No external fertilizer application or major plant protection measures are adopted for their cultivation as the Islands were declared to go organic decades back. Yet, Lakshadweep has one of the highest productivity of coconut compared with other coconut growing areas in India. Therefore, a question arises: how is such a high coconut productivity sustained? We try to answer by estimating in three main islands (i) the nutrients added to the soil via the litter generated by coconut palms and (ii) the role of soil microbiota, including arbuscular mycorrhizae, for the high productivity. Our results indicated that, besides adding a substantial quantum of organic carbon, twice the needed amount of nitrogen, extra 20% phosphorus to the already P-rich soils, 43-45% of potassium required by palms could be easily met by the total coconut biomass residues returned to the soil. Principal Component Analysis showed that soil organic carbon %, potassium, and organic carbon added via the palm litter and AM spore load scored >± 0.95 in PC1, whereas, available K in the soil, bacteria, actinomycetes, phosphate solubilizers and fluorescent pseudomonads scored above >± 0.95 in PC2. Based on our analysis, we suggest that the autochthonous nutrients added via the coconut biomass residues, recycled by the soil microbial communities, could be one of the main reasons for sustaining a high productivity of the coconut palms in Lakshadweep Islands, in the absence of any external fertilizer application, mimicking a semi-closed-loop forest ecosystem.
Assuntos
Fertilizantes , Microbiota , Carbono/análise , Cocos , Fertilizantes/análise , Nitrogênio/análise , Nutrientes/análise , Plantas , Potássio/análise , Solo/química , Microbiologia do SoloRESUMO
Follicle Stimulating Hormone (FSH) acts via FSH-Receptor (FSH-R) by employing cAMP as the dominant secondary messenger in testicular Sertoli cells (Sc) to support spermatogenesis. Binding of FSH to FSH-R, results the recruitment of the intracellular GTP binding proteins, either stimulatory Gαs or inhibitory Gαi that in turn regulate cAMP production in Sc. The cytosolic concentration of cAMP being generated by FSH-R thereafter critically determines the downstream fate of the FSH signalling. The pleiotropic action of FSH due to differential cAMP output during functional maturation of Sc has been well studied. However, the developmental and cellular regulation of the Gα proteins associated with FSH-R is poorly understood in Sc. In the present study, we report the differential transcriptional modulation of the Gα subunit genes by FSH mediated cAMP signalling in neonatal and pubertal rat Sc. Our data suggested that unlike in neonatal Sc, both the basal and FSH/forskolin induced expression of Gαs, Gαi-1, Gαi-2 and Gαi-3 transcripts was significantly (p < 0.05) up-regulated in pubertal Sc. Further investigations involving treatment of Sc with selective Gαi inhibitor pertussis toxin, confirmed the elevated expression of Gi subunits in pubertal Sc. Collectively our results indicated that the high level of Gαi subunits serves as a negative regulator to optimize cAMP production in pubertal Sc.
Assuntos
AMP Cíclico/metabolismo , Hormônio Foliculoestimulante/farmacologia , Subunidades alfa Gi-Go de Proteínas de Ligação ao GTP/metabolismo , Células de Sertoli/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Animais , Animais Recém-Nascidos , Células Cultivadas , Colforsina/farmacologia , Hormônio Foliculoestimulante/metabolismo , Subunidades alfa Gi-Go de Proteínas de Ligação ao GTP/genética , Regulação da Expressão Gênica/efeitos dos fármacos , Masculino , Toxina Pertussis/farmacologia , Ligação Proteica , Ratos Wistar , Receptores do FSH/genética , Receptores do FSH/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células de Sertoli/citologia , Células de Sertoli/metabolismo , Maturidade Sexual/fisiologia , Espermatogênese/efeitos dos fármacos , Espermatogênese/genéticaRESUMO
To understand bacterial community dynamics during the vermicomposting of lignin-rich coconut leaves using an indigenous isolate of an epigeic earthworm, Eudrilus sp., we employed amplicon-based pyrosequencing of the V1 to V3 region of the 16S rRNA genes. Total community DNA was isolated from two separate vermicomposting tanks in triplicate at four different stages of the process: pre-decomposition (15th day), initial vermicomposting (45th day), 50-70% vermicomposting (75th day) and mature vermicompost (105th day). Alpha diversity measurements revealed an increase in bacterial diversity till the 75th day, which then declined in the mature vermicompost. Beta diversity comparisons showed formation of distinct, stage-specific communities. In terms of relative abundance, the Acidobacteria, Actinobacteria, Chloroflexi, Gemmatimonadetes, Nitrospirae, Planctomycetes, TM7 and WS3 groups increased until the 50-70% vermicomposting stage (p = 0.05). During the same time, the abundance of Bacteroidetes and Proteobacteria decreased. In contrast, the levels of Firmicutes increased throughout the 105-day vermicomposting process. The distribution of the most abundant OTUs revealed that each stage of the vermicomposting process possessed its own unique microbiome. Predictions based on the OTUs present by PICRUSt suggested a functional shift in the microbiome during vermicomposting. Enzymes and pathways of lipid and lignin metabolism were predicted to be initially abundant, but by the end of the process, biosynthesis of secondary metabolites and plant beneficial properties were enriched. The study revealed that bacterial communities undergo a continuous change throughout the vermicomposting process and that certain OTUs associated with specific stages could be targets for further improvements in the process.
Assuntos
Biodiversidade , Cocos , Compostagem , Microbiota , Oligoquetos/metabolismo , Folhas de Planta/metabolismo , Microbiologia do Solo , Animais , Bactérias/classificação , Bactérias/genética , Proteínas de Bactérias/metabolismo , DNA Bacteriano/genética , Metagenômica/métodos , Oligoquetos/microbiologia , RNA Ribossômico 16S/genética , Reprodutibilidade dos Testes , Solo/químicaRESUMO
UNLABELLED: Deinococcus radiodurans and Escherichia coli expressing either PhoN, a periplasmic acid phosphatase, or PhoK, an extracellular alkaline phosphatase, were evaluated for uranium (U) bioprecipitation under two specific geochemical conditions (GCs): (i) a carbonate-deficient condition at near-neutral pH (GC1), and (ii) a carbonate-abundant condition at alkaline pH (GC2). Transmission electron microscopy revealed that recombinant cells expressing PhoN/PhoK formed cell-associated uranyl phosphate precipitate under GC1, whereas the same cells displayed extracellular precipitation under GC2. These results implied that the cell-bound or extracellular location of the precipitate was governed by the uranyl species prevalent at that particular GC, rather than the location of phosphatase. MINTEQ modeling predicted the formation of predominantly positively charged uranium hydroxide ions under GC1 and negatively charged uranyl carbonate-hydroxide complexes under GC2. Both microbes adsorbed 6- to 10-fold more U under GC1 than under GC2, suggesting that higher biosorption of U to the bacterial cell surface under GC1 may lead to cell-associated U precipitation. In contrast, at alkaline pH and in the presence of excess carbonate under GC2, poor biosorption of negatively charged uranyl carbonate complexes on the cell surface might have resulted in extracellular precipitation. The toxicity of U observed under GC1 being higher than that under GC2 could also be attributed to the preferential adsorption of U on cell surfaces under GC1. This work provides a vivid description of the interaction of U complexes with bacterial cells. The findings have implications for the toxicity of various U species and for developing biological aqueous effluent waste treatment strategies. IMPORTANCE: The present study provides illustrative insights into the interaction of uranium (U) complexes with recombinant bacterial cells overexpressing phosphatases. This work demonstrates the effects of aqueous speciation of U on the biosorption of U and the localization pattern of uranyl phosphate precipitated as a result of phosphatase action. Transmission electron microscopy revealed that location of uranyl phosphate (cell associated or extracellular) was primarily influenced by aqueous uranyl species present under the given geochemical conditions. The data would be useful for understanding the toxicity of U under different geochemical conditions. Since cell-associated precipitation of metal facilitates easy downstream processing by simple gravity-based settling down of metal-loaded cells, compared to cumbersome separation techniques, the results from this study are of considerable relevance to effluent treatment using such cells.
Assuntos
Deinococcus/fisiologia , Escherichia coli/fisiologia , Fosfatos/metabolismo , Compostos de Urânio/metabolismo , Urânio/metabolismo , Deinococcus/ultraestrutura , Escherichia coli/ultraestrutura , Concentração de Íons de Hidrogênio , Microscopia Eletrônica de TransmissãoRESUMO
OBJECTIVE: Present research work was aimed at formulation and evaluation of antifungal activity of miconazole nitrate (MN) vesicles vs C. albicans spp.
METHODS: Miconazole loaded vesicles were prepared by coacervation phase separation technique using nonionic surfactants and stabilizers. The antimycological activity of vesicles was performed using agar disc diffusion technique.
RESULTS: The miconazole nitrate lipid vesicles F5A and F5B showed maximum activity with higher zones of inhibition ie, 13.95+1.54 mm and 13.64+0.65 mm, respectively, after 3 days (For all comparisons, P<.05 was considered significant).
CONCLUSION: The findings of this study suggest antifungal potential of a novel preparation of miconazole nitrate vesicles vs Candida albicans in the treatment of mycoses in dermatological practice.
J Drugs Dermatol. 2016;15(6):734-737.
Assuntos
Antifúngicos/administração & dosagem , Candida albicans/efeitos dos fármacos , Portadores de Fármacos/administração & dosagem , Miconazol/administração & dosagem , Nanopartículas/administração & dosagem , Antifúngicos/química , Candida albicans/fisiologia , Portadores de Fármacos/química , Composição de Medicamentos , Humanos , Miconazol/química , Nanopartículas/químicaRESUMO
Oxidative stress resistant Deinococcus radiodurans surprisingly exhibited moderate sensitivity to tellurite induced oxidative stress (LD50 = 40 µM tellurite, 40 min exposure). The organism reduced 70% of 40 µM potassium tellurite within 5 h. Tellurite exposure significantly modulated cellular redox status. The level of ROS and protein carbonyl contents increased while the cellular reduction potential substantially decreased following tellurite exposure. Cellular thiols levels initially increased (within 30 min) of tellurite exposure but decreased at later time points. At proteome level, tellurite resistance proteins (TerB and TerD), tellurite reducing enzymes (pyruvate dehydrogense subunits E1 and E3), ROS detoxification enzymes (superoxide dismutase and thioredoxin reductase), and protein folding chaperones (DnaK, EF-Ts, and PPIase) displayed increased abundance in tellurite-stressed cells. However, remarkably decreased levels of key metabolic enzymes (aconitase, transketolase, 3-hydroxy acyl-CoA dehydrogenase, acyl-CoA dehydrogenase, electron transfer flavoprotein alpha, and beta) involved in carbon and energy metabolism were observed upon tellurite stress. The results demonstrate that depletion of reduction potential in intensive tellurite reduction with impaired energy metabolism lead to tellurite toxicity in D. radiodurans.
Assuntos
Deinococcus/efeitos dos fármacos , Deinococcus/enzimologia , Telúrio/toxicidade , Proteínas de Bactérias/metabolismo , Deinococcus/metabolismo , Metabolismo Energético , Oxirredução , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Compostos de Sulfidrila/metabolismoRESUMO
Narrow dentoalveolar ridges remain a serious challenge for the successful placement of endosseous implants. Several techniques for this procedure may be considered, such as guided bone regeneration, bone block grafting, and ridge splitting for bone expansion. The ridge split procedure provides a quicker method wherein an atrophic ridge can be predictably expanded and grafted with bone allograft or allograft, eliminating the need for second surgical site. Traditionally, osseous surgery has been performed by either manual or motor-driven instruments. Piezosurgery is a relatively new technique for osteotomy and osteoplasty that utilizes ultrasonic vibration which allows clean cutting with precise incisions. This case series describes reports of 2 such cases in which narrow mandibular ridge splitting was carried by mean of piezotome with immediate placement of implants in the osteotomy site. Five months later, the implants were uncovered followed by impression and restored with impant- supported porcelain-fused-to-metal crowns.
RESUMO
Two unicellular cyanobacteria Synechocystis sp. PCC 6803 and Synechococcus elongatus PCC 7942 showed contrasting responses to chromate stress with EC50 of 12 ± 2 and 150 ± 15 µM potassium dichromate respectively. There was no depletion of chromate in growth medium in both the cases. Using labeled chromate, very low accumulation (<1 nmol/10(8) cells) was observed in Synechocystis after incubation for 24 h in light. No accumulation of chromate could be observed in Synechococcus under these conditions. Chromate oxyanion is known to enter the cells using sulfate uptake channels. Therefore, inhibition of sulfate uptake caused by chromate was monitored using (35)S labeled sulfate. IC50 values of chromate for (35)sulfate uptake were higher in Synechococcus as compared to Synechocystis. The results suggested that the sulfate transporters in Synechococcus have lower affinity to chromate than those from Synechocystis possibly due to differences in affinity of sulfate receptors for chromate. Bioinformatic analyses revealed presence of sulfate and chromate transporters with considerable similarity; however, minor differences in these may play a role in their differential response to chromate. In both cases the IC50 values decreased when sulfate concentration was reduced in the medium indicating competitive inhibition of sulfate uptake by chromate. Interestingly, Synechococcus showed stimulation of growth at concentrations of chromate less than 100 µM, which affected its cell size without disturbing the ultrastructure and thylakoid organization. In Synechocystis, growth with 12 µM potassium dichromate damaged the ultrastructure and thylakoid organization with slight elongation of the cells. The results suggested that Synechococcus possesses efficient strategies to prevent entry and to remove chromate from the cell as compared to Synechocystis. This is the first time a differential response of Synechococcus 7942 and Synechocystis 6803 to chromate is reported. The contrasting characteristics observed in the two cyanobacteria will be useful in understanding the basis of resistance or susceptibility to chromate.
Assuntos
Cromatos/farmacologia , Erros Inatos do Metabolismo/genética , Synechococcus/efeitos dos fármacos , Synechocystis/efeitos dos fármacos , Cromatos/toxicidade , Regulação Bacteriana da Expressão Gênica/efeitos dos fármacos , Concentração Inibidora 50 , Microscopia Eletrônica de Transmissão , Alinhamento de Sequência , Sulfatos/metabolismo , Synechococcus/genética , Synechocystis/genéticaRESUMO
Two plant growth promoting bacteria designated as KiSII and RNF 267 isolated from the rhizosphere of coconut palms were identified as Serratia marcescens and Enterobacter sp. based on their phenotypic features, BIOLOG studies and 16S rRNA gene sequence analysis. Both bacteria exhibited phosphate solubilization, ammonification, and production of indole acetic acid, ß-1, 3 glucanase activities and 1-aminocyclopropane-1-carboxylate-deaminase activity. They could also tolerate a range of pH conditions, low temperature and salinity (NaCl). In addition, S. marcescens KiSII exhibited N- fixation potential, chitinase activity, siderophore production and antibiotics production. Seed bacterization with these bacteria increased the growth parameters of test plants such as paddy and cowpea over uninoculated control in green house assay. In coconut seedlings, significant increase in growth and nutrient uptake accompanied with higher populations of plant beneficial microorganisms in their rhizospheres were recorded on inoculation with both the PGPRs. The present study clearly revealed that PGPRs can aid in production of healthy and vigorous seedlings of coconut palm which are hardy perennial crops. They offer a scope to be developed into novel PGPR based bioinoculants for production of elite seedlings that can benefit the coconut farming community and the coconut based ecology.
Assuntos
Cocos/crescimento & desenvolvimento , Cocos/microbiologia , Enterobacter/isolamento & purificação , Enterobacter/fisiologia , Serratia marcescens/isolamento & purificação , Serratia marcescens/fisiologia , Cocos/metabolismo , Concentração de Íons de Hidrogênio , Fosfatos/metabolismo , Desenvolvimento Vegetal/fisiologia , Reguladores de Crescimento de Plantas , Rizosfera , Plântula/crescimento & desenvolvimento , Plântula/metabolismo , Plântula/microbiologia , Sementes/crescimento & desenvolvimento , Sementes/metabolismo , Sementes/microbiologia , Cloreto de Sódio/metabolismo , TemperaturaRESUMO
PURPOSE: Carbapenemases are the enzymes that can hydrolyze carbapenems and other ß-lactam antibiotics. These enzymes confer resistance to multiple antibiotics and act as a stumbling block in the treatment of infections caused by gram-negative bacteria. Therefore, rapid and specific detection of these enzymes is crucial for deciding the course of treatment and better clinical outcomes. MATERIAL AND METHODS: This study was conducted to compare various phenotypic and PCR based methods for the detection of carbapenemases in carbapenem- and colistin-resistant Klebsiella pneumoniae. One hundred clinical isolates of extensively resistant Klebsiella pneumoniae were included in the study. Phenotypic detection for carbapenemases was performed by Rapidec® Carba NP (Biomerieux), modified carbapenem inactivation method (mCIM), imipenem-ethylenediaminetetraacetic acid disk synergy (EDS), double disk synergy test using mercaptopropionic acid (DDST-MPA), and combined disk method (CD) and for colistin by microbroth dilution method. Genotypic detection for carbapenemases and colistin resistance was performed by targeted PCR. RESULTS: The sensitivity of Carba NP test and mCIM were positive in 95% and 96% respectively and specificity was 100% for both methods. The sensitivity of EDS, DDST-MPA, and CD were 55.6%, 88.9% and 54.5% respectively. Among the carbapenem resistance genes, blaOXA-48 (82%) genes were the most prevalent. Among metallo-beta lactamases, blaVIM (56%) was most common followed by blaNDM (54%) and blaIMP (20%). The mcr-1 gene for colistin resistance was not detected in any isolate. CONCLUSION: Among the five phenotypic assays analyzed, the mCIM is the most simple, inexpensive, accurate and reproducible method for carbapenemase detection in Klebsiella pneumoniae. The DDST-MPA test provides the best sensitivity for the detection of carbapenemases, although specificity is low. These tests, when applied in a clinical laboratory and assessed by the microbiologist, can help in guiding the course of treatment.
Assuntos
Colistina , Klebsiella pneumoniae , Humanos , Colistina/farmacologia , Análise Custo-Benefício , Testes de Sensibilidade Microbiana , beta-Lactamases/genética , beta-Lactamases/análise , Proteínas de Bactérias/genética , Proteínas de Bactérias/análise , Antibacterianos/farmacologia , Carbapenêmicos/farmacologiaRESUMO
Aging is associated with changes in circulating levels of various molecules, some of which remain undefined. We find that concentrations of circulating taurine decline with aging in mice, monkeys, and humans. A reversal of this decline through taurine supplementation increased the health span (the period of healthy living) and life span in mice and health span in monkeys. Mechanistically, taurine reduced cellular senescence, protected against telomerase deficiency, suppressed mitochondrial dysfunction, decreased DNA damage, and attenuated inflammaging. In humans, lower taurine concentrations correlated with several age-related diseases and taurine concentrations increased after acute endurance exercise. Thus, taurine deficiency may be a driver of aging because its reversal increases health span in worms, rodents, and primates and life span in worms and rodents. Clinical trials in humans seem warranted to test whether taurine deficiency might drive aging in humans.
Assuntos
Envelhecimento , Taurina , Animais , Humanos , Camundongos , Envelhecimento/sangue , Envelhecimento/efeitos dos fármacos , Envelhecimento/metabolismo , Senescência Celular , Haplorrinos , Longevidade/efeitos dos fármacos , Longevidade/fisiologia , Taurina/sangue , Taurina/deficiência , Taurina/farmacologia , Suplementos Nutricionais , Dano ao DNA/efeitos dos fármacos , Telomerase/metabolismoRESUMO
CONTEXT: The search for newer compounds against pathogenic species continues unabated due to drug resistance. Traditionally, Tagetes erecta Linn. (Compositae) has been used for the treatment of various parasitic and microbial diseases. OBJECTIVE: To evaluate the antioxidant activity of the ethanol extract of Tagetes erecta roots and its cytotoxicity against prostate and HeLa cancer cell lines followed by activity-guided isolation. MATERIALS AND METHODS: The antioxidant screening was carried out using diphenylpicrylhydrazyl (DPPH) radical scavenging assay with serial concentrations ranging from 2 to 100 µg/mL, and cytotoxicity was evaluated against prostate (PC-3) and HeLa cell lines using microculture tetrazolium test (MTT) assay with concentrations ranging from 500 to 1.89 µg/mL. Isolation of the ethanol extract was carried out using column chromatography whereby 21 isolates were obtained (T1-T21), and the most active isolate was subjected for characterization using ultraviolet (UV), infrared (IR), nuclear magnetic resonance (NMR), and mass spectroscopic techniques. RESULTS: The ethanol extract scavenged DPPH free radicals thereby exhibiting antioxidant activity with an IC50 of 35.9 µg/mL. In addition, the extract conferred noticeable cytotoxicity against the HeLa (LD50 of 164.28 µg/mL) and PC-3 cell lines (LD50 of 407.3 µg/mL). Among all the isolates, T3 showed antioxidant activity with IC50 of 11.56 µg/mL and cytotoxicity with LD50 of 12.5 µg/mL against HeLa and 30.25 µg/mL against PC-3 cell lines and was characterized as 2-ethynyl-5-(thiophen-2-yl) thiophene. DISCUSSION: The new thienyl compound (T3) exhibited profound antioxidant activity and cytotoxicity at relatively lower concentrations than the extract. CONCLUSION: The observations provide support for the ethnobotanical use of the plant.
Assuntos
Antineoplásicos Fitogênicos/farmacologia , Antioxidantes/farmacologia , Descoberta de Drogas , Neoplasias da Próstata/tratamento farmacológico , Tagetes/química , Tiofenos/farmacologia , Neoplasias do Colo do Útero/tratamento farmacológico , Antineoplásicos Fitogênicos/análise , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Antioxidantes/análise , Antioxidantes/química , Antioxidantes/isolamento & purificação , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Etnofarmacologia , Feminino , Sequestradores de Radicais Livres/análise , Sequestradores de Radicais Livres/química , Sequestradores de Radicais Livres/isolamento & purificação , Sequestradores de Radicais Livres/farmacologia , Células HeLa , Humanos , Índia , Concentração Inibidora 50 , Masculino , Estrutura Molecular , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/farmacologia , Raízes de Plantas/química , Tiofenos/análise , Tiofenos/química , Tiofenos/isolamento & purificaçãoRESUMO
Reconstruction of functional occlusion in case of a large surgical defect of the mandible involving partial mandibulectomy remains a significant challenge to the maxillofacial surgeon and prosthodontist. Removable appliances and the conventional implant-supported prosthesis are precluded in this case due to the absence of normal anatomical contours of the bone. In recent years, due to the advancement of technology, bone graft reconstruction with computer-guided rehabilitation of the functional occlusion has been advocated to reverse the debilitating effects of the hemimandibulectomy defect. This clinical report describes the prosthodontic management of fibular graft reconstructed mandible by computer-aided design-computer-aided manufacturing guided implant-supported prosthesis.
RESUMO
In this study, a multi-metal-tolerant natural bacterial isolate Providencia rettgeri strain KDM3 from an industrial effluent in Mumbai, India, showed high cadmium (Cd) tolerance. Providencia rettgeri grew in the presence of more than 100 ppm (880 µM) Cd (LD50 = 100 ppm) and accumulated Cd intracellularly. Following Cd exposure, a comparative proteome analysis revealed molecular mechanisms underlying Cd tolerance. Among a total of 69 differentially expressed proteins (DEPs) in Cd-exposed cells, de novo induction of ahpCF operon proteins and L-cysteine/L-cystine shuttle protein FliY was observed, while Dps and superoxide dismutase proteins were overexpressed, indicating upregulation of a robust oxidative stress defense. ENTRA1, a membrane transporter showing homology to heavy metal transporter, was also induced de novo. In addition, the protein disaggregation chaperone ClpB, trigger factor, and protease HslU were also overexpressed. Notably, 46 proteins from the major functional category of energy metabolism were found to be downregulated. Furthermore, the addition of P. rettgeri to Cd-spiked soil resulted in a significant reduction in the Cd content [roots (11%), shoot (50%), and grains (46%)] of the rice plants. Cd bioaccumulation of P. rettgeri improved plant growth and grain yield. We conclude that P. rettgeri, a highly Cd-tolerant bacterium, is an ideal candidate for in-situ bioremediation of Cd-contaminated agricultural soils.
RESUMO
BACKGROUND: The use of face masks has been associated with physiological changes in body. This study aims to know the changes in pulse rate and blood pressure components after wearing face masks during stairs climbing. METHODS: An experimental study was conducted among 60 apparently healthy young adults between 18-35 years of age. The pulse rate and blood pressure of the participants were recorded during rest at ground floor and after climbing the stairs till 5th floor at brisk and regular pace without wearing the face masks. The uniform KN95 masks were distributed and proper coverage of nose, mouth and chin were ensured. After 5 minutes interval, the pulse rate and blood pressure were recorded again at rest in ground floor and after climbing stairs with use of KN95 masks. RESULTS: At rest, the difference in mean pulse rate was statistically significant after wearing masks in participants between 21-25 years of age (86.46±14.59 bpm, p=0.014). After climbing the stairs, the mean pulse rate (131.16±18.48 bpm), mean systolic blood pressure (137.67±16.13 mmHg) and mean rate pressure product (182.87±41.70) were higher in participants (age group: 26-30 years) wearing masks and the difference was statistically significant (p=0.001; 0.013; 0.001respectively). During stairs climbing, the change in mean systolic blood pressure (32.66±16.73 mmHg), mean pulse pressure (43.77±24.64 mmHg) and mean rate pressure product (96.58±37.23) were higher in participants (age group: 26-30 years) and the difference was statistically significant (p=0.036; 0.047 and 0.009 respectively). CONCLUSIONS: The changes in systolic blood pressure, pulse pressure and rate pressure product are found to increase after wearing face masks during stairs climbing. It can be suggestive of increase workload to the heart by wearing face masks in addition to climbing the stairs.