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1.
Microb Pathog ; : 106781, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38969187

RESUMO

Leptospirosis is a zoonotic disease of global significance, contributing to morbidity and mortality worldwide. It is endemic to tropical regions, with outbreaks during monsoons. The disease manifestations are similar to that of other febrile illness such as dengue, malaria hence often misdiagnosed and underreported. The zoonoses if undetected, progresses to cause severe life-threatening complications also known as Weil's disease. Routine diagnostic tests are based on the detection of antibodies in patient serum and are not accurate during the initial phase of the infection. Therefore, it is necessary to detect novel biomarkers that can be used in early detection of leptospirosis. Circulating miRNAs are known to be promising biomarkers for various diseases including cancer, tuberculosis, influenza; hence in this study the potential of miRNAs as biomarkers for leptospirosis was evaluated. A total of 30 leptospirosis cases were screened for the differential expression of 10 miRNA by RT-qPCR assay. The differential expression was calculated by relative quantification using healthy individuals as controls. Among the 10 miRNA,3 miRNA, miR-28-5p, miR-302c-3p and miR-302a-3p were reported to exhibit a significant trend of upregulation. Further their role in immune pathways and biological processes was investigated by KEGG analysis and Gene Ontology. The 3 miRNAs were observed to target various immune response pathways, thus confirming their role in host immune response. Based on the results obtained in this study, miR-28-5p, miR-302c-3p and miR-302a-3p can be considered as potential biomarkers for the detection of leptospirosis.

2.
Am J Trop Med Hyg ; 110(6): 1230-1236, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38579700

RESUMO

Leptospirosis is a reemerging zoonotic disease of worldwide significance, endemic to the southern region of India, with clinical manifestations similar to other febrile illnesses; hence, it is often misdiagnosed and underreported. Inadequate information about the disease burden and the regional circulating serogroups contributes to its neglected disease status. This study aimed to identify the infecting Leptospira serogroup in the coastal region of Mangaluru and study the clinical symptoms and outcome among leptospirosis patients. Serum samples were collected from 30 patients with confirmed leptospirosis admitted to a tertiary care center in Mangaluru and screened by microscopic agglutination test (MAT) for the infecting serogroup. The clinical profile of these cases was reviewed, and data regarding epidemiological factors such as age, sex, complications, and mortality were recorded. The MAT identified a higher occurrence of serogroup Bataviae (n = 7, 43.75%) and serogroup Australis (n = 5, 31.25%) compared with other serogroups screened in this study population. Patients were aged 16 to 65 years, with a predominance of males. The clinical presentation of leptospirosis ranged from a mild febrile illness to multiorgan failure. Fever (n = 29, 96%) was the common clinical presentation, followed by myalgia, nausea, and abdominal pain. Acute kidney injury, acute respiratory distress syndrome, and multiple organ dysfunction syndrome were the common complications observed. Determining the circulating serogroup is necessary to understand the epidemiology and diversity of Leptospira serogroups among animals and humans to strategize appropriate preventive measures.


Assuntos
Leptospira , Leptospirose , Sorogrupo , Humanos , Leptospirose/epidemiologia , Leptospirose/diagnóstico , Leptospirose/microbiologia , Índia/epidemiologia , Masculino , Adulto , Pessoa de Meia-Idade , Feminino , Leptospira/classificação , Leptospira/isolamento & purificação , Adolescente , Idoso , Adulto Jovem , Estudos Prospectivos , Testes de Aglutinação
3.
J Oral Biosci ; 66(2): 272-280, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38508491

RESUMO

BACKGROUND: Pulpitis primarily arises from the pulp space infection by oral microbiota. Vital pulp therapy is a minimally invasive approach that relies on assessing the severity of pulpal inflammation to facilitate repair. However, the current evaluation methods prescribed by the American Association of Endodontics are subjective, leading to ambiguity in assessment. Therefore, this review aims to explore molecular strategies for evaluating the severity of pulpal inflammation to accurately predict the success of pulp vitality preservation in clinical settings. METHODOLOGY: This review was conducted by searching relevant keywords, such as irreversible pulpitis, pulpitis biomarkers, molecular diagnosis, inflammation, and genomic strategies, in databases such as PubMed, Web of Science, and Scopus to address the subjective nature of diagnosis. The data included in this review were collected up to April 2023. The literature search revealed well-documented limitations in clinically assessing the pulp inflammatory. Molecular approaches that aid in clinical differentiation between irreversible and reversible pulpitis may potentially enhance favorable outcomes in vital pulp therapy. Non-invasive diagnostic methods for pulpal assessment would also be valuable for determining whether the inflamed pulp is reversible, irreversible, or necrotic. CONCLUSION: The present review examines the various molecular diagnostic approaches that have revolutionized the medical field and are considered the most promising empirical methodologies for the proactive detection of pulpal diseases. It also provides comprehensive insights into the current diagnostic methods, associated challenges, next-generation strategies, and future directions for diagnosing the severity of pulp inflammation.


Assuntos
Pulpite , Humanos , Pulpite/diagnóstico , Biomarcadores/análise , Biomarcadores/metabolismo , Polpa Dentária/microbiologia , Polpa Dentária/patologia
4.
Acta Microbiol Immunol Hung ; 70(4): 272-277, 2023 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-37975913

RESUMO

Atherosclerosis is a progressive disease marked by the accumulation of lipids and fibrous components in the large arteries. It is one of the primary causes of heart disease and stroke. Periodontal diseases encompass conditions like gingivitis and periodontitis, which are multifactorial diseases associated with dysbiotic plaque biofilms that trigger an immune-inflammatory host response, eventually resulting in the destruction of periodontal tissues. Links between periodontal disease and atherosclerosis may be based on direct invasion of periodontal pathogens or inflammatory mechanisms triggered by bacteria related to periodontal lesions, locally or systemically, that may impact the initiation of the atherosclerotic lesion. The presence of periodontal pathogens within an atheromatous lesion implies hematogenous dissemination. The invasion of atheroma by periodontal pathogens results in changes in the proatherogenic and proinflammatory properties of endothelial cells, leading to endothelial dysfunction, which is a hallmark of atherosclerosis. Clinical and epidemiological studies have offered sufficient evidence of periodontitis having an adverse effect on systemic health, including atherosclerosis; however, a direct causal effect has not yet been proved. This review aims to analyse scientific results regarding the mechanism by which periodontal pathogens may cause atherosclerosis as well as to describe the role of Porphyromonas gingivalis in atherosclerotic plaque development and progression.


Assuntos
Aterosclerose , Periodontite , Placa Aterosclerótica , Humanos , Placa Aterosclerótica/complicações , Placa Aterosclerótica/microbiologia , Placa Aterosclerótica/patologia , Células Endoteliais/patologia , Aterosclerose/complicações , Aterosclerose/microbiologia , Aterosclerose/patologia , Periodontite/complicações , Periodontite/microbiologia , Porphyromonas gingivalis
5.
Indian J Microbiol ; 63(3): 281-290, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37781016

RESUMO

The role of periodontal pathogens in the initiation and progression of atherosclerosis has been extensively researched, yet a precise causal mechanism has not been established. The subgingival microbiota may be a source of dissemination and may contribute to the development of atherosclerosis; hence this study attempted to characterize and compare the subgingival and atherosclerotic plaques. Plaque samples were subjected to 16S rRNA-based metagenomics to study microbiota associated with subgingival and atherosclerotic plaques collected from patients with coronary artery disease. The PCoA analysis showed that the microbiomes of subgingival plaques were highly scattered and showed a diverse microbial composition, unlike the atherosclerotic plaques that did not show evident variability in the microbial composition and formed a close distinct group. The abundance of various genera in the subgingival plaques revealed Fusobacterium (11%), Acinetobacter (13%), Veillonella (9%), and Prevotella (11%) among the top ten genera. The atherosclerotic plaques contained Acinetobacter (39%), Chryseobacterium (9%), Rhizobium (5%), and Staphylococcus (4%). All the patients examined in this study had either generalized or localized periodontitis with varying degrees of severity. The community microbiota analysis revealed that 22 bacterial genera were shared between two different plaques, with Acinetobacter being dominant. Based on the Human Oral Microbiome Database, 55% of the shared microbiota in this study have been listed as periodontal microbiota, with some of them found in increased proportions in patients with periodontitis suggesting the translocation of bacteria from the periodontal pockets into the circulation. This study provides valuable insights into the possible relationship between periodontal pathogens and atherosclerotic cardiovascular disease.

6.
Acta Microbiol Immunol Hung ; 70(3): 177-186, 2023 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-37505986

RESUMO

Irreversible pulpitis is an inflammation of the tooth pulp caused by an opportunity-driven invasion of the pulp space by oral microbiota typically prevalent in the oral cavity. Microbial organisms are extensively recognised to be the fundamental cause of endodontic infections and treatment failures. Previously, bacterial species responsible for these infections were largely recognised using conventional microbial culture techniques, lending credence to the widely held belief that anaerobic Gram-negative bacteria frequently enter the pulp space and trigger endodontic infections. The advent of novel technologies grants the advantage of detecting and studying microbial populations via an amalgamation of the modern "Omics" techniques and meticulous bioinformatics analysis, additionally detecting the metatranscriptome, metaproteome and metabolome along with the metagenome. Amongst these analytical strategies, metagenomic analyses are essentially pragmatic for investigating the oral microbiome. Metagenomics favor not only assessment of microbial composition in diseased conditions, but also contributes to detection of novel, potentially pathogenic species inclusive of non-viable bacteria. The present review describes current knowledge of root canal microbiome, including its composition and functional attributes, the novel strategies available for detection of microbiome as well as challenges associated and provides some crucial pointers for areas of future research.


Assuntos
Microbiota , Pulpite , Humanos , Pulpite/microbiologia , Bactérias/genética , Inflamação
7.
Acta Microbiol Immunol Hung ; 69(4): 332-344, 2022 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-36370369

RESUMO

In this study we report the whole genome sequencing (WGS) based analysis of blood-borne Campylobacter fetus subsp. fetus MMM01 isolated from a diabetic patient to obtain deeper insights in to the virulence and host adaptability. The sequenced genome of C. fetus subsp. fetus MMM01 along with reference genomes retrieved from NCBI was subjected to various in-silico analysis including JSpecies, MLST server, PATRIC server, VFanalyzer, CARD, PHASTER to understand their phylogenetic relation, virulence and antimicrobial resistance profile. The genome had a size of 1,788,790 bp, with a GC content of 33.09%, nearly identical to the reference strain C. fetus subsp. fetus 82-40. The MLST based phylogenetic tree constructed revealed the polyphyletic branching and MMM01 (ST25) was found to be closely related to ST11, both belong to the sap-A serotype which are more common in human infections. VFanalyzer identified 88 protein-coding genes coding for several virulence factors including Campylobacter adhesion to fibronectin, flagellar apparatus, cytolethal distending toxin operons and Campylobacter invasion antigen proteins which enhance the virulence of bacteria along with resistance genes against antibiotics including fluoroquinolone, chloramphenicol, tetracycline, and aminoglycoside in MMM01, which points to enhanced survival and pathogenicity of this zoonotic pathogen. It was interesting to find that MMM01 lacked FGI-II island found in most of the clinical isolates, which encoded CRISPR Cas and prophage II regions. More details about the complexity and evolution of this zoonotic pathogen could be learned from future studies that concentrate on comparative genome analysis using larger genome datasets.


Assuntos
Campylobacter fetus , Fatores de Virulência , Humanos , Campylobacter fetus/genética , Filogenia , Tipagem de Sequências Multilocus , Índia , Fatores de Virulência/genética
8.
Microb Pathog ; 172: 105767, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36096457

RESUMO

The emergence of highly virulent multidrug-resistant P. aeruginosa has become increasingly evident among hospital-acquired infections and has raised the need for alternative therapies. Phage therapy can be one such alternative to antibiotic therapy to combat multidrug-resistant pathogenic bacteria, but this requires the availability of phages with a broad host range. In this study, isolation and molecular characterisation of P. aeruginosa specific phages were carried out. A total of 17 phages isolated showed different spectra of activity and efficiency of lysis against 82 isolates of P. aeruginosa obtained from clinical samples (n = 13), hospital effluent (n = 46) and fish processing plant effluent (n = 23). Antibiotic susceptibility test results revealed multi-drug resistance in 61 of the total 82 isolates. Three new jumbo lytic P. aeruginosa specific broad host range phages were isolated and characterised in this present study belonged to the family Myoviridae (order Caudovirales). The genetic analysis of ɸU5 revealed that phage has a genome size of 282.6 kbp with 373 putative open reading frames (ORFs), and its genetic architecture is similar to phiKZ like jumbo phages infecting P. aeruginosa. The bacteriophages isolated in this study had lytic ability against biofilm-forming and multidrug-resistant P. aeruginosa and could be candidates for further studies towards phage therapy.


Assuntos
Bacteriófagos , Fagos de Pseudomonas , Pseudomonas aeruginosa/genética , Fagos de Pseudomonas/genética , Bacteriófagos/genética , Genoma Viral , Antibacterianos/farmacologia
9.
J Microbiol Methods ; 195: 106438, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35248601

RESUMO

Leptospirosis is a re-emerging anthropo-zoonotic infection of worldwide significance caused by the pathogenic spirochete (Leptospira interrogans) of the genus Leptospira, predominant in tropical/temperate regions and endemic to areas receiving heavy rainfall and flooding. Clinical presentation is similar to that of other febrile illnesses exhibiting mild symptoms which are often self-limiting. Hence, Leptospirosis is often mis-diagnosed and remains untreated progressing to Weil's Disease which is fatal. As only 30% of cases are diagnosed in endemic countries, Leptospirosis remains as a neglected zoonotic disease of tropical regions, due to poor diagnostic facilities and mild, asymptomatic disease manifestations which are often neglected. As this zoonosis is reported to cause periodical outbreaks, it is a major public health concern. Although diagnostic facilities are available, they are not accessible in technology-limited settings and are limited to certain hospitals and reference laboratories. This review is about the various methods used for the detection of Leptospirosis and their significance. It highlights the need for an appropriate diagnostic test for the rapid detection of leptospirosis in order to initiate immediate antibiotic therapy.


Assuntos
Leptospira interrogans , Leptospira , Leptospirose , Animais , Surtos de Doenças , Leptospirose/diagnóstico , Zoonoses/diagnóstico
10.
Antibiotics (Basel) ; 11(2)2022 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-35203804

RESUMO

Antibiotic resistance, and, in a broader perspective, antimicrobial resistance (AMR), continues to evolve and spread beyond all boundaries. As a result, infectious diseases have become more challenging or even impossible to treat, leading to an increase in morbidity and mortality. Despite the failure of conventional, traditional antimicrobial therapy, in the past two decades, no novel class of antibiotics has been introduced. Consequently, several novel alternative strategies to combat these (multi-) drug-resistant infectious microorganisms have been identified. The purpose of this review is to gather and consider the strategies that are being applied or proposed as potential alternatives to traditional antibiotics. These strategies include combination therapy, techniques that target the enzymes or proteins responsible for antimicrobial resistance, resistant bacteria, drug delivery systems, physicochemical methods, and unconventional techniques, including the CRISPR-Cas system. These alternative strategies may have the potential to change the treatment of multi-drug-resistant pathogens in human clinical settings.

11.
Indian Heart J ; 73(2): 218-220, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33865522

RESUMO

Links between periodontitis and atherosclerosis can be predicted based on inflammatory mechanisms initiated by bacteria associated with periodontal lesions, which then influence the initiation or propagation of the atherosclerotic lesion. This study aimed to detect the presence of three periodontal pathogens, in atheromatous plaques of patients with coronary artery disease. Subgingival and atherosclerotic plaque samples were obtained from 80 patients scheduled for CABG or angioplasty. A nested PCR was done for the detection of the pathogens in the plaque samples. Porphyromonas gingivalis, Tanarella forsythia, and Treponema denticola were detected in 10%, 12.5%, and 1.3% of the atherosclerotic plaque samples respectively. It was also observed that patients whose atherosclerotic plaques tested positive for one or more of the pathogens had chronic periodontitis.


Assuntos
Doença da Artéria Coronariana , Placa Aterosclerótica , Doença da Artéria Coronariana/diagnóstico , DNA Bacteriano/genética , Humanos , Porphyromonas gingivalis/genética , Treponema denticola/genética
12.
Infect Genet Evol ; 92: 104880, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33905893

RESUMO

The growing incidence of dengue outbreaks in the state of Karnataka prompted us to study the circulating dengue virus (DENV) and their proportion among the suspected cases of dengue patients during the disease outbreak at Mysuru district of Southern India. The presence of the DENV in a patient's serum sample was identified by RT-PCR using previously published primer pairs targeting CprM gene. DENV serotyping was carried out by semi-nested multiplex PCR using serotype-specific primers and nucleotide sequencing. Three hundred fifty-five samples of serum from suspected dengue cases were collected, and 203 samples (57.18%) were found positives. In 2016, DENV-4 (97.87%) was found to be the most dominant DENV serotype either alone or as co-infection, followed by DENV-2 (8.51%) and DENV-3 (4.25%). In 47 positive cases, co-infection with more than one serotype was detected in 4 cases (8.51%). The analysis of the dengue cases in 2017, DENV-4 was dominating serotype (33.97%), followed by the emergence of DENV-2 (32.05%), DENV-3 (25.64%), and DENV-1 (25.00%). Our study also reports the circulation of all four DENV serotypes in the Mysuru district of Southern India, with concurrent infections rate of 16.66% in 2017. The present study provides information regarding the genetic variation among the circulating DENV serotype in an Indian state of Karnataka. The need for the studying genetic diversity of DENV will be useful during the continuous monitoring for disease burden as well as the development of appropriate prophylactic measures to control the spread of dengue infection.


Assuntos
Coinfecção/epidemiologia , Dengue/epidemiologia , Surtos de Doenças , Sorogrupo , Adolescente , Adulto , Idoso , Criança , Coinfecção/virologia , Dengue/virologia , Vírus da Dengue/genética , Feminino , Humanos , Índia/epidemiologia , Masculino , Pessoa de Meia-Idade , Prevalência , Adulto Jovem
13.
Arch Microbiol ; 203(6): 2925-2939, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33770232

RESUMO

An auxotrophic mutant of nontyphoidal Salmonella (NTS) strain (Salmonella Oslo) was phenotypically characterized in this study. The characterization was based on phenotype, morphology, motility, biofilm forming ability, growth kinetics, etc. The phenotypic results from the above experiments determined that the mutant showed variation in phenotypic characters from that of wild-type strain. Subsequently, mutant and wild-type NTS were subjected to epithelial cell invasion and intracellular replication assays. The real-time PCR analysis was also performed to analyse expression of tumor inhibiting cytokine genes and virulence genes post-bacterial infection in cell lines. The mutant showed highest invasion potential than wild-type NTS whereas the replication of mutant was slower in both the cell lines. Similar to the wild-type strain, the mutant also retained the cytotoxic potential when analysed in vitro. Furthermore, the expression of proinflammatory cytokine genes such as TNF-α and IL-1ß was upsurged with the downregulation of anti-inflammatory cytokine genes like TGF-ß, IL-6 and IL-10 post-infection of the mutant strain in cell lines. In addition, virulence genes of Salmonella pathogenicity island one and two of mutant were downregulated in vitro except invA in HeLa cell line. Therefore, the auxotrophic mutant showed positive attributes of a potential antitumor agent in terms of expressing tumor inhibiting cytokine genes when assessed in vitro. Though the study did not check the tumor inhibitory effect of NTS strain directly, findings of the study emphasizes on the development of a novel strain of NTS with less virulence and more immunogenic traits to inhibit tumor cells.


Assuntos
Citocinas/genética , Salmonella/genética , Animais , Células HEK293 , Células HeLa , Humanos , Fenótipo , Salmonella/patogenicidade , Virulência/genética
14.
Appl Microbiol Biotechnol ; 105(2): 441-455, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33394144

RESUMO

COVID-19 is a disease caused by SARS-CoV-2 capable of causing mild to severe infections in humans. Since its first appearance in China in December 2019, the pandemic has spread rapidly throughout the world. Despite considerable efforts made to contain the disease, the virus has continued its prevalence in many countries with varying degrees of clinical manifestations. To contain this pandemic, collaborative approach involving accurate diagnosis, epidemiology, surveillance, and prophylaxis is essential. However, proper diagnosis using rapid technologies plays a crucial role. With increasing incidence of COVID-19 cases, the accurate and early detection of the SARS-CoV-2 is need of the hour for effective prevention and management of COVID-19 cases as well as to curb its spread. RT-qPCR assay is considered to be the gold standard for the early detection of virus, but this protocol has limited application to use as bedside test because of its technical complexity. To address these challenges, several POC assays have been developed to facilitate the COVID-19 diagnosis outside the centralized testing laboratories as well to accelerate the clinical decision making with a least turnaround time. Hence, in this report, we review different nucleic acid-based and serological techniques available for the diagnosis and effective prevention of COVID-19. KEY POINTS : • Provides comprehensive information on the different diagnostic tools available for COVID-19 • Nucleic acid based tests or antigen detection tests are used for diagnostic purpose • Accurate diagnosis is essential for the efficient management of COVID-19.


Assuntos
Teste de Ácido Nucleico para COVID-19/métodos , Teste Sorológico para COVID-19/métodos , COVID-19/diagnóstico , COVID-19/prevenção & controle , Anticorpos Antivirais/sangue , COVID-19/virologia , Teste de Ácido Nucleico para COVID-19/tendências , Teste Sorológico para COVID-19/tendências , Humanos , RNA Viral/genética , SARS-CoV-2/genética , Sensibilidade e Especificidade
15.
Virus Res ; 291: 198222, 2021 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-33166565

RESUMO

The envelope glycoprotein (E) is the smallest structural component of SARS-CoVs; plays an essential role in the viral replication starting from envelope formation to assembly. The in silico analysis of 2086 whole genome sequences from India performed in this study provides the first observation on the extensive deletion of amino acid residues in the C-terminal region of the envelope glycoprotein in 34 Indian SARS-CoV-2 genomes. These amino acid deletions map to the homopentameric interface and PDZ binding motif (PBM) present in the C-terminal region of E protein as well as immediately after the reverse primer binding region as per Charité protocol in 26 of these genomes, hence, their detection through RT-qPCR may not be hampered and therefore E gene-based RT-qPCR would still detect these isolates. Eight genomes from the State of Odisha had deletion even in the primer binding site. It is possible that the deletions in the C-terminal region of E protein of these genomes are a result of adapting to a newer geographical area and host. The information on the clinical status was available only for 9 out of 34 cases and these were asymptomatic. However, further studies are indispensable to understand the functional consequences of amino acid deletion in the C terminal region of SARS-CoV-2 envelope protein in the viral pathogenesis and host adaptation.


Assuntos
Proteínas do Envelope de Coronavírus/genética , SARS-CoV-2/genética , Adulto , Sequência de Aminoácidos , Simulação por Computador , Proteínas do Envelope de Coronavírus/imunologia , Epitopos de Linfócito B , Feminino , Deleção de Genes , Genoma Viral , Humanos , Índia , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase em Tempo Real , SARS-CoV-2/isolamento & purificação
16.
Microorganisms ; 8(7)2020 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-32635463

RESUMO

It has been observed that not all strains of Vibrio vulnificus are virulent. Determining the virulence of strains that are frequently present in seafood is of significance for ensuring seafood safety. This study is an attempt to predict the virulence of seafood-borne V. vulnificus isolated along the Mangaluru Coast, India. The isolates tested possessed a vcgC gene sequence with high similarity to that in the clinical strain. Transcriptional analysis of core virulence genes in seafood isolate E4010 showed the phenomenon of contact-mediated expression of rtxA1 which correlated well with the actin disintegration and cytotoxicity. These results suggest that the seafood isolates tested in this study possess a functional RtxA1 which could help in initiating the infection. However, other putative virulence genes such as vvpE encoding an extracellular protease, vvhA encoding hemolysin, flp encoding tad pilin and ompU encoding fibronectin-binding protein were also constitutively expressed. Virulence-associated attributes such as cytotoxicity and adherence matched the response of the clinical strain (p > 0.05). On the other hand, the environmental strains showed higher serum sensitivity compared with the clinical strain. These findings show that the part of virulence attributes required for the disease process might be intact in these isolates.

17.
J Genomics ; 8: 7-10, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31892994

RESUMO

In recent years, the concept of bacteria-mediated cancer therapy has gained significant attention as an alternative to conventional therapy. The focus has been on non-typhoidal Salmonella (NTS), particularly S. Typhimurium, for its anti-cancer properties, however, other NTS serovars such as Salmonella Oslo, which are associated with foodborne illnesses could potentially be effective anti-cancer agents. Here, we report the draft genome sequence of Salmonella Oslo isolated from seafood and its laboratory generated auxotrophic mutant.

18.
J Microbiol Methods ; 166: 105747, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31639359

RESUMO

A SYBR green based qPCR assay targeting a unique region of gyrB was developed for the detection of Vibrio vulnificus. The specificity of the assay was studied using V. vulnificus and other bacterial strains belonging to Vibrio and non-Vibrio species. The assay unambiguously distinguished V.vulnificus with a sensitivity of 101 CFU/mL in pure culture while 102CFU/g was detected in clam meat homogenate with an efficiency of ≥98%.The utility of the qPCR assay was validated with naturally incurred seafood samples, where 24 out of 59(40.67%) seafood samples tested positive for V. vulnificus after 6-8 h enrichment in APW-P broth. In contrast, conventional PCR could detect only 11 samples (18.64%). Our results showed that qPCR assay developed in this study could be used as a rapid method for screening seafood samples for the presence of V. vulnificus, as the assay can be completed within 9-12 h including the enrichment of seafood in APW-P broth. The gyrB targeted qPCR developed in this study can provide excellent results on the presence and load of V. vulnificus in naturally contaminated samples quickly and efficiently; thus it could find application as a routine test in the seafood industry for the analysis V. vulnificus.


Assuntos
Microbiologia de Alimentos/métodos , Reação em Cadeia da Polimerase/métodos , Reação em Cadeia da Polimerase em Tempo Real/métodos , Frutos do Mar/microbiologia , Vibrio vulnificus/isolamento & purificação , Benzotiazóis , DNA Girase/genética , Diaminas , Compostos Orgânicos/química , Quinolinas
19.
Can J Microbiol ; 65(9): 681-690, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31075207

RESUMO

Gastric acidity is one of the earliest host defences faced by ingested organisms, and successful pathogens need to overcome this hurdle. The objective of this study was the systematic assessment of acid-stress response of Vibrio vulnificus isolated from coastal regions of Mangaluru. Acid-shock experiments were carried out at pH 4.0 and pH 4.5, with different experimental conditions expected to produce a varied acid response. Exposure to mild acid before the acid shock was favourable to the bacteria but was dependent on cell population and pH of the media and was independent of the strains tested. Lysine-dependent acid response was demonstrated with reference to the previously identified lysine decarboxylase system. Additionally, the results showed that inoculation into oysters provided some level of protection against acid stress. Increased expression of lysine/cadaverine genes was observed upon the addition of ground oyster and was confirmed by quantitative real-time PCR. The potential role of ornithine was analyzed with regard to acid stress, but no change in the survival pattern was observed. These findings highlight the physiology of bacteria in acid stress.


Assuntos
Ostreidae/microbiologia , Estresse Fisiológico , Vibrio vulnificus/fisiologia , Ácidos , Animais , Proteínas de Bactérias/metabolismo , Carboxiliases/metabolismo , Meio Ambiente , Genótipo , Concentração de Íons de Hidrogênio , Índia , Vibrio vulnificus/enzimologia , Vibrio vulnificus/genética , Vibrio vulnificus/crescimento & desenvolvimento
20.
J Med Microbiol ; 68(4): 616-621, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30839251

RESUMO

We report the use of next generation sequencing (NGS) for investigating an outbreak of 13 cases of Serratia marcescens blood stream infections in a non-Neonatal Intensive Care Unit (non-NICU) setting in a tertiary care hospital in India over 5 months. Thirteen cases of sepsis due to S. marcescens were identified in various Intensive Care Units (ICUs) over 5 months. Environmental surveillance identified isolates in the adult ICU (AICU). Antibiogram did not correlate with timeline. Sequencing libraries were prepared using Nextera XT chemistry (Illumina). Based on NGS, two clusters were identified. Cluster 1 had environmental and clinical isolates from the AICU and cluster 2 were isolates from the Coronary Care Unit (CCU). NICU and Paediatric ICU isolates did not belong to any cluster. Polyclonal outbreaks best identified by NGS can occur simultaneously. Good infection prevention practices like hand hygiene for compounded medicines and surface cleaning helped end the outbreak.


Assuntos
Surtos de Doenças/estatística & dados numéricos , Infecções por Serratia/epidemiologia , Serratia marcescens/genética , Estudos de Casos e Controles , Infecção Hospitalar/epidemiologia , Infecção Hospitalar/microbiologia , Surtos de Doenças/prevenção & controle , Monitoramento Epidemiológico , Higiene das Mãos , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Índia/epidemiologia , Recém-Nascido , Controle de Infecções , Unidades de Terapia Intensiva Neonatal , Sepse/epidemiologia , Sepse/microbiologia , Infecções por Serratia/sangue , Centros de Atenção Terciária , Sequenciamento Completo do Genoma
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