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1.
Proc Natl Acad Sci U S A ; 120(33): e2305465120, 2023 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-37549252

RESUMO

Microbes evolve rapidly by modifying their genomes through mutations or through the horizontal acquisition of mobile genetic elements (MGEs) linked with fitness traits such as antimicrobial resistance (AMR), virulence, and metabolic functions. We conducted a multicentric study in India and collected different clinical samples for decoding the genome sequences of bacterial pathogens associated with sepsis, urinary tract infections, and respiratory infections to understand the functional potency associated with AMR and its dynamics. Genomic analysis identified several acquired AMR genes (ARGs) that have a pathogen-specific signature. We observed that blaCTX-M-15, blaCMY-42, blaNDM-5, and aadA(2) were prevalent in Escherichia coli, and blaTEM-1B, blaOXA-232, blaNDM-1, rmtB, and rmtC were dominant in Klebsiella pneumoniae. In contrast, Pseudomonas aeruginosa and Acinetobacter baumannii harbored blaVEB, blaVIM-2, aph(3'), strA/B, blaOXA-23, aph(3') variants, and amrA, respectively. Regardless of the type of ARG, the MGEs linked with ARGs were also pathogen-specific. The sequence type of these pathogens was identified as high-risk international clones, with only a few lineages being predominant and region-specific. Whole-cell proteome analysis of extensively drug-resistant K. pneumoniae, A. baumannii, E. coli, and P. aeruginosa strains revealed differential abundances of resistance-associated proteins in the presence and absence of different classes of antibiotics. The pathogen-specific resistance signatures and differential abundance of AMR-associated proteins identified in this study should add value to AMR diagnostics and the choice of appropriate drug combinations for successful antimicrobial therapy.


Assuntos
Antibacterianos , Escherichia coli , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Escherichia coli/genética , beta-Lactamases/genética , beta-Lactamases/farmacologia , Proteômica , Farmacorresistência Bacteriana , Farmacorresistência Bacteriana Múltipla/genética , Klebsiella pneumoniae , Testes de Sensibilidade Microbiana
2.
Indian J Med Res ; 159(1): 91-101, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38344919

RESUMO

BACKGROUND OBJECTIVES: The clinical course of COVID-19 and its prognosis are influenced by both viral and host factors. The objectives of this study were to develop a nationwide platform to investigate the molecular epidemiology of SARS-CoV-2 (Severe acute respiratory syndrome Corona virus 2) and correlate the severity and clinical outcomes of COVID-19 with virus variants. METHODS: A nationwide, longitudinal, prospective cohort study was conducted from September 2021 to December 2022 at 14 hospitals across the country that were linked to a viral sequencing laboratory under the Indian SARS-CoV-2 Genomics Consortium. All participants (18 yr and above) who attended the hospital with a suspicion of SARS-CoV-2 infection and tested positive by the reverse transcription-PCR method were included. The participant population consisted of both hospitalized as well as outpatients. Their clinical course and outcomes were studied prospectively. Nasopharyngeal samples collected were subjected to whole genome sequencing to detect SARS-CoV-2 variants. RESULTS: Of the 4972 participants enrolled, 3397 provided samples for viral sequencing and 2723 samples were successfully sequenced. From this, the evolution of virus variants of concern including Omicron subvariants which emerged over time was observed and the same reported here. The mean age of the study participants was 41 yr and overall 49.3 per cent were female. The common symptoms were fever and cough and 32.5 per cent had comorbidities. Infection with the Delta variant evidently increased the risk of severe COVID-19 (adjusted odds ratio: 2.53, 95% confidence interval: 1.52, 4.2), while Omicron was milder independent of vaccination status. The independent risk factors for mortality were age >65 yr, presence of comorbidities and no vaccination. INTERPRETATION CONCLUSIONS: The authors believe that this is a first-of-its-kind study in the country that provides real-time data of virus evolution from a pan-India network of hospitals closely linked to the genome sequencing laboratories. The severity of COVID-19 could be correlated with virus variants with Omicron being the milder variant.


Assuntos
COVID-19 , Feminino , Humanos , Masculino , Progressão da Doença , Hospitais , Estudos Prospectivos , SARS-CoV-2/genética , Adulto , Adolescente , Idoso , Pessoa de Meia-Idade
3.
Langmuir ; 39(48): 17201-17215, 2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-37991461

RESUMO

Solid lubricant coatings play a critical role in enhancing the tribological properties of engineering materials, particularly in aerospace and biomedical applications. Ti6Al4V is widely used in aerospace and defense industries due to its excellent mechanical properties and high strength-to-weight ratio. In this regard, a solid lubricant metal matrix composite (MMC) clad was successfully fabricated over Ti6Al4V. A full factorial (L16) was successfully implemented to investigate the interaction of process parameters for laser power and scanning speed with response outputs, such as the clad layer thickness and microhardness. The microstructural study of the clad confirmed the presence of dark and bright phases of the microstructure with cylindrical, elliptical, and lamellar structures. This showed the presence of molybdenum and sulfide phases (MoS2, TiS, CuS) and the presence of a nickel phase (TiNi, NiS, CuNi), confirmed through X-ray diffraction (XRD) analysis and energy-dispersive X-ray (EDX) spectroscopy; these phases bestowed hardness as well as solid lubricating properties on the clad. The microhardness of the clad was found to be 2-3 times that of the substrate material. The wear behavior of the clad was studied in the load range of 5-15 N; the coefficient of friction (0.33 for clad and 0.5 for base), wear track depth profile, and wear mechanism revealed that the cladded sample has higher wear resistance as compared to the substrate material. The worn morphology showed that microcutting and microplowing are the major phenomena of wear occurrence. Further, X-ray photoelectron spectroscopy (XPS) analysis was performed to determine the binding energy of the compound formed at the clad zone, which can predict the most significant phase for the alteration of the mechanical behavior of the solid lubrication clad.

4.
Genomics ; 113(6): 3951-3966, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34619341

RESUMO

Microbes evolve rapidly by modifying their genome through mutations or acquisition of genetic elements. Antimicrobial resistance in Helicobacter pylori is increasingly prevalent in India. However, limited information is available about the genome of resistant H. pylori isolated from India. Our pan- and core-genome based analyses of 54 Indian H. pylori strains revealed plasticity of its genome. H. pylori is highly heterogenous both in terms of the genomic content and DNA sequence homology of ARGs and virulence factors. We observed that the H. pylori strains are clustered according to their geographical locations. The presence of point mutations in the ARGs and absence of acquired genetic elements linked with ARGs suggest target modifications are the primary mechanism of its antibiotic resistance. The findings of the present study would help in better understanding the emergence of drug-resistant H. pylori and controlling gastric disorders by advancing clinical guidance on selected treatment regimens.


Assuntos
Infecções por Helicobacter , Helicobacter pylori , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Farmacorresistência Bacteriana/genética , Genômica , Infecções por Helicobacter/tratamento farmacológico , Infecções por Helicobacter/genética , Helicobacter pylori/genética , Humanos , Virulência/genética
6.
World J Microbiol Biotechnol ; 33(10): 178, 2017 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-28932951

RESUMO

On screening of endolithic actinobacteria from a granite rock sample of Meghalaya for antibacterial compound, a novel antibacterial compound CCp1 was isolated from the fermentation broth of Actinomadura sp. AL2. On purification of the compound based on chromatographic techniques followed by characterization with FT-IR, UV-visible, 1H NMR, 13C NMR and mass spectrometry, the molecular formula of the compound was generated as C20H17N3O2, a furopyrimidine derivative. In vitro antibacterial activity of the compound was evaluated against both Gram positive and negative bacteria by agar well diffusion assay. The compound had lowest MIC (2.00 µg/ml) for Bacillus subtilis and highest MIC (> 64 µg/ml) for Staphylococcus epidermidis and Pseudomonas aeruginosa. The study revealed that the compound has potential antibacterial activity. The mode of action of the antibacterial compound was evaluated through in silico studies for its ability to bind DNA gyrase, 30S RNA molecules, OmpF porins and N-Acetylglucosamine-1-phosphate uridyltransferase (GlmU). The antibacterial compound demonstrated more favorable docking with DNA gyrase, 30S RNA molecules and OmpF porins than GlmU which support the antibacterial compound CCp1 can be as a promising broad spectrum antibiotic agent with "multitarget" characteristics.


Assuntos
Actinobacteria/crescimento & desenvolvimento , Antibacterianos/química , Furanos/química , Pirimidinas/química , Actinobacteria/metabolismo , Antibacterianos/isolamento & purificação , Antibacterianos/farmacologia , Bacillus subtilis/efeitos dos fármacos , Simulação por Computador , Fermentação , Furanos/isolamento & purificação , Furanos/farmacologia , Espectroscopia de Ressonância Magnética , Testes de Sensibilidade Microbiana , Modelos Moleculares , Simulação de Acoplamento Molecular , Pseudomonas aeruginosa/efeitos dos fármacos , Pirimidinas/isolamento & purificação , Pirimidinas/farmacologia , Espectroscopia de Infravermelho com Transformada de Fourier , Staphylococcus epidermidis/efeitos dos fármacos
7.
iScience ; 27(2): 108764, 2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38313048

RESUMO

Non-alcoholic fatty liver disease (NAFLD) is an emerging global health problem and a potential risk factor for metabolic diseases. The bidirectional interactions between liver and gut made dysbiotic gut microbiome one of the key risk factors for NAFLD. In this study, we reported an increased abundance of Collinsella aerofaciens in the gut of obese and NASH patients living in India. We isolated C. aerofaciens from the fecal samples of biopsy-proven NASH patients and observed that their genome is enriched with carbohydrate metabolism, fatty acid biosynthesis, and pro-inflammatory functions and have the potency to increase ethanol level in blood. An animal study indicated that mice supplemented with C. aerofaciens had increased levels of circulatory ethanol, high levels of hepatic hydroxyproline, triglyceride, and inflammation in the liver. The present findings indicate that perturbation in the gut microbiome composition is a key risk factor for NAFLD.

8.
Mol Cancer ; 12: 147, 2013 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-24261856

RESUMO

BACKGROUND: VEGF receptor 2 (VEGFR2) inhibitors, as efficient antiangiogenesis agents, have been applied in the cancer treatment. However, recently, most of these anticancer drugs have some adverse effects. Discovery of novel VEGFR2 inhibitors as anticancer drug candidates is still needed. METHODS: We used α-santalol and analyzed its inhibitory effects on human umbilical vein endothelial cells (HUVECs) and Prostate tumor cells (PC-3 or LNCaP) in vitro. Tumor xenografts in nude mice were used to examine the in vivo activity of α-santalol. RESULTS: α-santalol significantly inhibits HUVEC proliferation, migration, invasion, and tube formation. Western blot analysis indicated that α-santalol inhibited VEGF-induced phosphorylation of VEGFR2 kinase and the downstream protein kinases including AKT, ERK, FAK, Src, mTOR, and pS6K in HUVEC, PC-3 and LNCaP cells. α-santalol treatment inhibited ex vivo and in vivo angiogenesis as evident by rat aortic and sponge implant angiogenesis assay. α-santalol significantly reduced the volume and the weight of solid tumors in prostate xenograft mouse model. The antiangiogenic effect by CD31 immunohistochemical staining indicated that α-santalol inhibited tumorigenesis by targeting angiogenesis. Furthermore, α-santalol reduced the cell viability and induced apoptosis in PC-3 cells, which were correlated with the downregulation of AKT, mTOR and P70S6K expressions. Molecular docking simulation indicated that α-santalol form hydrogen bonds and aromatic interactions within the ATP-binding region of the VEGFR2 kinase unit. CONCLUSION: α-santalol inhibits angiogenesis by targeting VEGFR2 regulated AKT/mTOR/P70S6K signaling pathway, and could be used as a potential drug candidate for cancer therapy.


Assuntos
Inibidores da Angiogênese/farmacologia , Neovascularização Patológica/tratamento farmacológico , Neoplasias da Próstata/tratamento farmacológico , Proteínas Proto-Oncogênicas c-akt/metabolismo , Sesquiterpenos/farmacologia , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/antagonistas & inibidores , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica , Células Endoteliais da Veia Umbilical Humana , Humanos , Masculino , Camundongos , Camundongos Nus , Modelos Moleculares , Simulação de Acoplamento Molecular , Terapia de Alvo Molecular , Sesquiterpenos Policíclicos , Próstata/metabolismo , Próstata/patologia , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Proteínas Proto-Oncogênicas c-akt/genética , Ratos , Transdução de Sinais/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
9.
Mol Cancer ; 12: 82, 2013 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-23895055

RESUMO

BACKGROUND: Anti-angiogenesis targeting VEGFR2 has been considered as an important strategy for cancer therapy. Tylophorine is known to possess anti-inflammatory and antitumor activity, but its roles in tumor angiogenesis, the key step involved in tumor growth and metastasis, and the involved molecular mechanism is still unknown. Therefore, we examined its anti-angiogenic effects and mechanisms in vitro and in vivo. METHODS: We used tylophorine and analyzed its inhibitory effects on human umbilical vein endothelial cells (HUVEC) in vitro and Ehrlich ascites carcinoma (EAC) tumor in vivo. RESULTS: Tylophorine significantly inhibited a series of VEGF-induced angiogenesis processes including proliferation, migration, and tube formation of endothelial cells. Besides, it directly inhibited VEGFR2 tyrosine kinase activity and its downstream signaling pathways including Akt, Erk and ROS in endothelial cells. Using HUVECs we demonstrated that tylophorine inhibited VEGF-stimulated inflammatory responses including IL-6, IL-8, TNF-α, IFN-γ, MMP-2 and NO secretion. Tylophorine significantly inhibited neovascularization in sponge implant angiogenesis assay and also inhibited tumor angiogenesis and tumor growth in vivo. Molecular docking simulation indicated that tylophorine could form hydrogen bonds and aromatic interactions within the ATP-binding region of the VEGFR2 kinase unit. CONCLUSION: Tylophorine exerts anti-angiogenesis effects via VEGFR2 signaling pathway thus, may be a viable drug candidate in anti-angiogenesis and anti-cancer therapies.


Assuntos
Alcaloides/farmacologia , Inibidores da Angiogênese/farmacologia , Antineoplásicos Fitogênicos/farmacologia , Indolizinas/farmacologia , Neovascularização Fisiológica/efeitos dos fármacos , Fenantrenos/farmacologia , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/antagonistas & inibidores , Alcaloides/administração & dosagem , Alcaloides/química , Inibidores da Angiogênese/administração & dosagem , Inibidores da Angiogênese/química , Animais , Antineoplásicos Fitogênicos/administração & dosagem , Antineoplásicos Fitogênicos/química , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Citocinas/metabolismo , Modelos Animais de Doenças , Feminino , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Indolizinas/administração & dosagem , Indolizinas/química , Masculino , Metaloproteinase 2 da Matriz/metabolismo , Camundongos , Conformação Molecular , Simulação de Acoplamento Molecular , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Neoplasias/mortalidade , Neoplasias/patologia , Óxido Nítrico/metabolismo , Fenantrenos/administração & dosagem , Fenantrenos/química , Ligação Proteica/efeitos dos fármacos , Domínios e Motivos de Interação entre Proteínas , Transdução de Sinais/efeitos dos fármacos , Carga Tumoral/efeitos dos fármacos , Tylophora/química , Fator A de Crescimento do Endotélio Vascular/metabolismo , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/química , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
10.
Ann Indian Acad Neurol ; 26(6): 936-942, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38229619

RESUMO

Objective: One or more inexcitable motor (IM) nerves are common during electrodiagnostic (EDx) study in Guillain-Barré syndrome (GBS). This study assessed the dose-effect relationship of IM nerves on outcome in patients with acute inflammatory demyelinating polyneuropathy (AIDP) and acute motor and/or sensory axonal neuropathy (AMAN and AMSAN). Materials and Methods: Eighty-eight GBS patients admitted during May 2018-June 2023 underwent detailed clinical evaluation and EDx study. Admission and follow-up disability were assessed on a 0-10 Clinical Grading Scale (CGS). Outcome was recovery at 6 months, defined as good (CGS <3) and poor (CGS ≥3). Binary multivariate logistic regression with backward elimination was used to calculate independent predictors of outcome. Results: Proportion of patients with complete recovery decreased significantly with increasing numbers of IM nerves (P < 0.01). Seventy-six patients were followed for 6 months. Among patients with IM nerves (n = 28), complete recovery was similar between AIDP and axonal GBS (70% vs. 50%, respectively; P = 0.40). However, in patients with recordable compound muscle action potentials (CMAPs) in all the motor nerves (n = 26), axonal GBS had significantly poor recovery compared to AIDP (75% vs. 9.1%; P = 0.01). Among patients receiving intravenous immunoglobulin (IVIg; n = 42), poor recovery was seen in 53.6% with IM nerves compared to 35.7% without (P = 0.28), while it was 37.5% versus 5.6% (P = 0.04), respectively, in those who did not receive IVIg (n = 34). However, only admission disability (odds ratio [OR] 0.88, 95% confidence interval [CI] 0.81-0.97; P = 0.007) was found to be an independent predictor of outcome. Conclusion: Although increasing numbers of IM nerves were associated with poor outcome on univariate analysis, they did not predict 6 months' outcome independently. Outcome did not differ between axonal GBS and AIDP among those with IM nerves. IVIg improved outcome in patients with IM nerves.

11.
Microbiol Resour Announc ; 12(11): e0064523, 2023 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-37819118

RESUMO

We report complete genome sequence of Lactiplantibacillus plantarum BBC32B, which was isolated from human feces sample and submitted to Microbial-Type Culture Collection (MTCC), India with deposition number MTCC 25432. The bacteria from Lactobacillaceae family contained 3,411,152 bp; 3,425 protein coding genes, sharing 69.67% average nucleotide identity with closest species of Lactobacillus brevis ATCC367.

12.
J Hum Lact ; 39(2): 343-352, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-34581614

RESUMO

BACKGROUND: The composition of the human milk microbiome is highly variable and multifactorial. Milk microbiota from various countries show striking differences. There is a paucity of data from healthy lactating Indian mothers. RESEARCH AIM: To describe the milk microbiota of healthy North Indian women, using a culture-independent, targeted metagenomic approach. METHODS: We recruited exclusively breastfeeding mothers (N = 22) who had vaginally delivered full-term singleton infants in a tertiary care hospital less than 1 week previously and had not recently consumed systemic antibiotics. Milk samples (5 ml) were collected aseptically, and microbial deoxyribonucleic acid was extracted. Microbial composition and diversity were determined using a 454-pyrosequencing platform. Core genera were identified, and their relative abundances ranked. Heatmaps showing the variation of the ranked abundances and Shannon index were obtained using R. RESULTS: Participants (all exclusively vegetarian) had a mean (SD) age of 27.2 (3.4) years, postnatal age of 3.9 (1.6) days and gestation 38 (1.2) weeks. The dominant phylum was Proteobacterium (relative abundance 84%) and dominant genus Pseudomonas (relative abundance 61.78%). Eleven species of Pseudomonas were identified, all generally considered nonpathogenic. Based on abundance patterns of the core genera, the milk samples could be grouped: (a) dominated by Pseudomonas with low diversity; (b) less Pseudomonas and high diversity; and (c) dominated by Pseudomonas but high diversity. All neonates were healthy and gaining weight well at 1 month of age. CONCLUSIONS: Healthy, lactating, vegetarian, North Indian women who deliver at term gestation and have no recent exposure to antibiotics, have a unique milk microbiome dominated by Pseudomonas.


Assuntos
Microbiota , Leite Humano , Lactente , Recém-Nascido , Feminino , Humanos , Adulto , Leite Humano/microbiologia , Lactação , Aleitamento Materno , Mães
13.
Nat Commun ; 14(1): 4060, 2023 07 10.
Artigo em Inglês | MEDLINE | ID: mdl-37429848

RESUMO

SARS-CoV-2 infection is known for causing broncho-alveolar inflammation. Interleukin 9 (IL-9) induces airway inflammation and bronchial hyper responsiveness in respiratory viral illnesses and allergic inflammation, however, IL-9 has not been assigned a pathologic role in COVID-19. Here we show, in a K18-hACE2 transgenic (ACE2.Tg) mouse model, that IL-9 contributes to and exacerbates viral spread and airway inflammation caused by SARS-CoV-2 infection. ACE2.Tg mice with CD4+ T cell-specific deficiency of the transcription factor Forkhead Box Protein O1 (Foxo1) produce significantly less IL-9 upon SARS-CoV-2 infection than the wild type controls and they are resistant to the severe inflammatory disease that characterises the control mice. Exogenous IL-9 increases airway inflammation in Foxo1-deficient mice, while IL-9 blockade reduces and suppresses airway inflammation in SARS-CoV-2 infection, providing further evidence for a Foxo1-Il-9 mediated Th cell-specific pathway playing a role in COVID-19. Collectively, our study provides mechanistic insight into an important inflammatory pathway in SARS-CoV-2 infection, and thus represents proof of principle for the development of host-directed therapeutics to mitigate disease severity.


Assuntos
COVID-19 , Interleucina-9 , Animais , Camundongos , Interleucina-9/genética , Enzima de Conversão de Angiotensina 2 , SARS-CoV-2 , Inflamação
14.
Future Microbiol ; 18: 173-186, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36916516

RESUMO

Aim: To characterize extensively drug-resistant Pseudomonas aeruginosa from a patient with diarrhea. Materials & methods: Antimicrobial susceptibility was tested by the disk diffusion method. The P. aeruginosa genome was sequenced to identify virulence, antibiotic resistance and prophages encoding genes. Results: P. aeruginosa had a wide spectrum of resistance to antibiotics. Genomic analysis of P. aeruginosa revealed 76 genes associated with antimicrobial resistance, xenobiotic degradation and the type three secretion system. Conclusion: This is the first report on diarrhea associated with P. aeruginosa. Since no other organism was identified, the authors assume that the patient had dysbiosis due to antibiotic exposure, leading to antibiotic-associated diarrhea. The in vivo toxicity expressed by the pathogen may be associated with T3SS.


Assuntos
Infecções por Pseudomonas , Pseudomonas aeruginosa , Humanos , Pseudomonas aeruginosa/metabolismo , Antibacterianos/farmacologia , Antibacterianos/metabolismo , Genômica , Virulência/genética , Diarreia , Infecções por Pseudomonas/tratamento farmacológico , Infecções por Pseudomonas/metabolismo , Farmacorresistência Bacteriana Múltipla/genética , Testes de Sensibilidade Microbiana
15.
BMC Bioinformatics ; 13 Suppl 17: S26, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23282079

RESUMO

BACKGROUND: The Nymphaeales (waterlilly and relatives) lineage has diverged as the second branch of basal angiosperms and comprises of two families: Cabombaceae and Nymphaceae. The classification of Nymphaeales and phylogeny within the flowering plants are quite intriguing as several systems (Thorne system, Dahlgren system, Cronquist system, Takhtajan system and APG III system (Angiosperm Phylogeny Group III system) have attempted to redefine the Nymphaeales taxonomy. There have been also fossil records consisting especially of seeds, pollen, stems, leaves and flowers as early as the lower Cretaceous. Here we present an in silico study of the order Nymphaeales taking maturaseK (matK) and internal transcribed spacer (ITS2) as biomarkers for phylogeny reconstruction (using character-based methods and Bayesian approach) and identification of motifs for DNA barcoding. RESULTS: The Maximum Likelihood (ML) and Bayesian approach yielded congruent fully resolved and well-supported trees using a concatenated (ITS2+ matK) supermatrix aligned dataset. The taxon sampling corroborates the monophyly of Cabombaceae. Nuphar emerges as a monophyletic clade in the family Nymphaeaceae while there are slight discrepancies in the monophyletic nature of the genera Nymphaea owing to Victoria-Euryale and Ondinea grouping in the same node of Nymphaeaceae. ITS2 secondary structures alignment corroborate the primary sequence analysis. Hydatellaceae emerged as a sister clade to Nymphaeaceae and had a basal lineage amongst the water lilly clades. Species from Cycas and Ginkgo were taken as outgroups and were rooted in the overall tree topology from various methods. CONCLUSIONS: MatK genes are fast evolving highly variant regions of plant chloroplast DNA that can serve as potential biomarkers for DNA barcoding and also in generating primers for angiosperms with identification of unique motif regions. We have reported unique genus specific motif regions in the Order Nymphaeles from matK dataset which can be further validated for barcoding and designing of PCR primers. Our analysis using a novel approach of sequence-structure alignment and phylogenetic reconstruction using molecular morphometrics congrue with the current placement of Hydatellaceae within the early-divergent angiosperm order Nymphaeales. The results underscore the fact that more diverse genera, if not fully resolved to be monophyletic, should be represented by all major lineages.


Assuntos
Código de Barras de DNA Taxonômico/métodos , Endorribonucleases/genética , Nucleotidiltransferases/genética , Nymphaeaceae/classificação , Teorema de Bayes , Cloroplastos/genética , Simulação por Computador , Código de Barras de DNA Taxonômico/estatística & dados numéricos , DNA de Cloroplastos/genética , DNA Intergênico/genética , DNA de Plantas/genética , Endorribonucleases/química , Fósseis , Marcadores Genéticos , Funções Verossimilhança , Conformação de Ácido Nucleico , Nucleotidiltransferases/química , Nymphaeaceae/genética , Filogenia , Estrutura Secundária de Proteína , Alinhamento de Sequência
16.
J Biomol Struct Dyn ; 40(20): 10454-10469, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34229570

RESUMO

One major obstacle in designing a successful therapeutic regimen to combat COVID-19 pandemic is the frequent occurrence of mutations in the SARS-CoV-2 resulting in patient to patient variations. Out of the four structural proteins of SARS-CoV-2 namely, spike, envelope, nucleocapsid and membrane, envelope protein governs the virus pathogenicity and induction of acute-respiratory-distress-syndrome which is the major cause of death in COVID-19 patients. These effects are facilitated by the viroporin (ion-channel) like activities of the envelope protein. Our current work reports metagenomic analysis of envelope protein at the amino acid sequence level through mining all the available SARS-CoV-2 genomes from the GISAID and coronapp servers. We found majority of mutations in envelope protein were localized at or near PDZ binding motif. Our analysis also demonstrates that the acquired mutations might have important implications on its structure and ion-channel activity. A statistical correlation between specific mutations (e.g. F4F, R69I, P71L, L73F) with patient mortalities were also observed, based on the patient data available for 18,691 SARS-CoV-2-genomes in the GISAID database till 30 April 2021. Albeit, whether these mutations exist as the cause or the effect of co-infections and/or co-morbid disorders within COVID-19 patients is still unclear. Moreover, most of the current vaccine and therapeutic interventions are revolving around spike protein. However, emphasizing on envelope protein's (1) conserved epitopes, (2) pathogenicity attenuating mutations, and (3) mutations present in the deceased patients, as reported in our present study, new directions to the ongoing efforts of therapeutic developments against COVID-19 can be achieved by targeting envelope viroporin.


Assuntos
COVID-19 , SARS-CoV-2 , Proteínas Viroporinas , Humanos , COVID-19/mortalidade , COVID-19/virologia , Mutação , SARS-CoV-2/genética , Proteínas Viroporinas/genética
17.
Gene ; 847: 146857, 2022 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-36100116

RESUMO

Helicobacter pylori is a ubiquitous bacterium and contributes significantly to the burden of chronic gastritis, peptic ulcers, and gastric cancer across the world. Adaptive phenotypes and virulence factors in H. pylori are heterogeneous and dynamic. However, limited information is available about the molecular nature of antimicrobial resistance phenotypes and virulence factors of H. pylori strains circulating in India. In the present study, we analyzed the whole genome sequences of 143 H. pylori strains, of which 32 are isolated from two different regions (eastern and southern) of India. Genomic repertoires of individual strains show distinct region-specific signatures. We observed lower resistance phenotypes and genotypes in the East Indian (Kolkata) H. pylori isolates against amoxicillin and furazolidone antibiotics, whereas higher resistance phenotypes to metronidazole and clarithromycin. Also, at molecular level, a greater number of AMR genes were observed in the east Indian H. pylori isolates as compared to the southern Indian isolates. From our findings, we suggest that metronidazole and clarithromycin antibiotics should be used judicially in the eastern India. However, no horizontally acquired antimicrobial resistance gene was observed in the current H. pylori strains. The comparative genome analysis shows that the number of genes involved in virulence, disease and resistance of H. pylori isolated from two different regions of India is significantly different. Single-nucleotide polymorphisms (SNPs) based phylogenetic analysis distinguished H. pylori strains into different clades according to their geographical locations. Conditionally beneficial functions including antibiotic resistance phenotypes that are linked with faster evolution rates in the Indian isolates.


Assuntos
Anti-Infecciosos , Infecções por Helicobacter , Helicobacter pylori , Humanos , Amoxicilina , Antibacterianos/farmacologia , Claritromicina/farmacologia , Farmacorresistência Bacteriana/genética , Furazolidona , Genômica , Infecções por Helicobacter/tratamento farmacológico , Infecções por Helicobacter/microbiologia , Helicobacter pylori/genética , Metronidazol , Testes de Sensibilidade Microbiana , Filogenia , Fatores de Virulência , Polimorfismo de Nucleotídeo Único
18.
Sci Adv ; 7(37): eabg5016, 2021 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-34516769

RESUMO

High-salt diet (HSD) modulates effector and regulatory T cell functions and promotes tissue inflammation in autoimmune diseases. However, effects of HSD and its association with gut microbiota in tumor immunity remain undefined. Here, we report that HSD induces natural killer (NK) cell­mediated tumor immunity by inhibiting PD-1 expression while enhancing IFNγ and serum hippurate. Salt enhanced tumor immunity when combined with a suboptimal dose of anti-PD1 antibody. While HSD-induced tumor immunity was blunted upon gut microbiota depletion, fecal microbiota transplantation (FMT) from HSD mice restored the tumor immunity associated with NK cell functions. HSD increased the abundance of Bifidobacterium and caused increased gut permeability leading to intratumor localization of Bifidobacterium, which enhanced NK cell functions and tumor regression. Intratumoral injections of Bifidobacterium activated NK cells, which inhibited tumor growth. These results indicate that HSD modulates gut microbiome that induces NK cell­dependent tumor immunity with a potential translational perspective.

19.
Front Cell Infect Microbiol ; 11: 622474, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34094994

RESUMO

Background: The incidence of preterm birth (PTB) in India is around 13%. Specific bacterial communities or individual taxon living in the vaginal milieu of pregnant women is a potential risk factor for PTB and may play an important role in its pathophysiology. Besides, bacterial taxa associated with PTB vary across populations. Objective: Conduct a comparative analysis of vaginal microbiome composition and microbial genomic repertoires of women who enrolled in the Interdisciplinary Group for Advanced Research on Birth Outcomes - A DBT India Initiative (GARBH-Ini) pregnancy cohort to identify bacterial taxa associated with term birth (TB) and PTB in Indian women. Methods: Vaginal swabs were collected during all three trimesters from 38 pregnant Indian women who delivered spontaneous term (n=20) and preterm (n=18) neonates. Paired-end sequencing of V3-V4 region of 16S rRNA gene was performed using the metagenomic DNA isolated from vaginal swabs (n=115). Whole genome sequencing of bacterial species associated with birth outcomes was carried out by shotgun method. Lactobacillus species were grown anaerobically in the De Man, Rogosa and Sharpe (MRS) agar culture medium for isolation of genomic DNA and whole genome sequencing. Results: Vaginal microbiome of both term and preterm samples reveals similar alpha diversity indices. However, significantly higher abundance of Lactobacillus iners (p-value All_Trimesters<0.02), Megasphaera sp (p-value1st_Trimester <0.05), Gardnerella vaginalis (p-value2nd_Trimester= 0.01) and Sneathia sanguinegens (p-value2nd_Trimester <0.0001) were identified in preterm samples whereas higher abundance of L. gasseri (p-value3rd_Trimester =0.010) was observed in term samples by Wilcoxon rank-sum test. The relative abundance of L. iners, and Megasphaera sp. were found to be significantly different over time between term and preterm mothers. Analyses of the representative genomes of L. crispatus and L. gasseri indicate presence of secretory transcriptional regulator and several ribosomally synthesized antimicrobial peptides correlated with anti-inflammatory condition in the vagina. These findings indicate protective role of L. crispatus and L. gasseri in reducing the risk of PTB. Conclusion: Our findings indicate that the dominance of specific Lactobacillus species and few other facultative anaerobes are associated with birth outcomes.


Assuntos
Nascimento Prematuro , Feminino , Fusobactérias , Humanos , Índia , Recém-Nascido , Lactobacillus , Gravidez , Nascimento Prematuro/epidemiologia , RNA Ribossômico 16S/genética , Vagina
20.
Gene ; 805: 145908, 2021 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-34411649

RESUMO

Transcriptome profiling of Vrindavani and Tharparkar cattle (n = 5 each) revealed that more numbers of genes were dysregulated in Vrindavani than in Tharparkar. A contrast in gene expression was observed with 18.9 % of upregulated genes in Vrindavani downregulated in Tharparkar and 17.8% upregulated genes in Tharparkar downregulated in Vrindavani. Functional annotation of genes differentially expressed in Tharparkar and Vrindavani revealed that the systems biology in Tharparkar is moving towards counteracting the effects due to heat stress. Unlike Vrindavani, Tharparkar is not only endowed with higher expression of the scavengers (UBE2G1, UBE2S, and UBE2H) of misfolded proteins but also with protectors (VCP, Serp1, and CALR) of naïve unfolded proteins. Further, higher expression of the antioxidants in Tharparkar enables it to cope up with higher levels of free radicals generated as a result of heat stress. In this study, we found relevant genes dysregulated in Tharparkar in the direction that can counter heat stress.


Assuntos
Resposta ao Choque Térmico/genética , Resposta ao Choque Térmico/fisiologia , Animais , Bovinos/genética , Expressão Gênica/genética , Perfilação da Expressão Gênica/métodos , Regulação da Expressão Gênica/genética , Índia , Biologia de Sistemas/métodos , Transcriptoma/genética
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