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1.
Int J Dent Hyg ; 22(1): 106-115, 2024 Feb.
Article in English | MEDLINE | ID: mdl-37793081

ABSTRACT

INTRODUCTION: The world's population is in a demographic transition with a rising ageing population. Tooth loss is frequent among older people resulting in the replacement of natural teeth using complete or partial dentures. YouTube™ is the second most popular website in the world and is being increasingly used to access health care information. The aim of this study is to evaluate the usefulness and reliability of the information in YouTube™ videos regarding denture care. METHODS: The YouTube™ website was used to systematically search for videos using the keyword 'denture care'. Videos meeting the eligibility criteria were assessed separately by two independent researchers. The usefulness of the videos was assessed using the Global Quality Assessment Scale and a customized usefulness scoring scheme. Based on these scores, the usefulness of the videos was categorized as low, medium and high. A modified DISCERN tool (mDISCERN) was used for assessing reliability with scores ranging from 0 to 5. Other video characteristics like source/ownership of the videos, duration, views, likes, dislikes, number of days posted, like ratio, view ratio, interaction index and Video Power Index were also obtained. Statistical analysis was carried out using the Kruskal-Wallis test, Spearman correlation test and multiple linear regression analysis. RESULTS: A total of 120 videos were included. Based on the usefulness score, the usefulness of 65.8% of videos were classified as low, 32.5% were medium and 1.6% had high usefulness. The mDISCERN score for 74.2% of videos was 2 or below 2 indicating that the majority of videos had low reliability. Video characteristics did not differ significantly according to the usefulness of videos. Videos uploaded by dentists or dental hygienists had significantly higher usefulness scores (p < 0.001) in comparison to videos uploaded by other sources. However, reliability scores did not differ based on the sources of the videos. Video reliability was found to have a significant (B = 2.08, p < 0.001) positive association with video usefulness. CONCLUSION: YouTube™ cannot be recommended as the only source of information for denture care as most videos received low usefulness and reliability ratings in our study. Dentists and dental health professionals could take an active part in enhancing denture care-related content on YouTube™ and enable patients to have adequate and reliable knowledge of denture hygiene practices.


Subject(s)
Social Media , Humans , Aged , Reproducibility of Results , Video Recording , Emotions , Dentures
2.
J Hum Reprod Sci ; 16(1): 29-35, 2023.
Article in English | MEDLINE | ID: mdl-37305773

ABSTRACT

Background: Serum anti-Mullerian hormone (AMH) is a significant determinant of ovarian reserve. It is still not clear about the rate at which AMH declines with age and varies across populations. Aim: The present study examined the AMH levels specific to the North and South Indian populations and attempted to establish an age-dependent reference parametrically. Settings and Design: This was a prospective study in a tertiary centre. Materials and Methods: Serum samples were collected apparently from 650 infertile women (327 from North and 323 from South Indians). AMH was measured using an electrochemiluminescent technique. Statistical Analysis Used: Comparison of the AMH data between North and South regions was done by independent t-test. For each age, seven empirical percentiles (3rd, 10th, 25th, 50th, 75th, 90th and 95th) were applied. AMH nomograms for the 3rd, 10th, 25th, 50th, 75th, 85th, 90th and 95th percentiles were produced using the lambda-mu-sigma method. Results: AMH levels remarkably decreased with increasing age in the North Indian population, but in the South Indian population, they did not decline beyond 1.5 ng/mL. Further, in the North Indian population, AMH levels were significantly higher in the age group of 22-30 years (4.4 ng/mL) than in the South Indian population (2.04 ng/mL). Conclusion: The present study suggests a major geographical difference in mean AMH levels according to their age and ethnic background, regardless of their subjacent pathologies.

3.
J Family Med Prim Care ; 11(7): 3459-3464, 2022 Jul.
Article in English | MEDLINE | ID: mdl-36387737

ABSTRACT

The present study aimed to assess the knowledge and attitude of female schoolteachers toward cervical cancer. Materials and Method: A cross-sectional study was conducted among 256 Government female schoolteachers aged 22-60 years in Salem city, Tamil Nadu. A self-administered questionnaire which assessed the levels of knowledge (6 items) and attitude (4 items) regarding cervical cancer was employed and responses were recorded on a three-point Likert scale. Data were analysed using Statistical Package for Social Sciences (SPSS) software version 20.0. Results: Overall adequate knowledge and good attitude regards to cervical cancer was observed among 60% and 66.8% of schoolteachers, respectively. Participants in the age range of 31-45 years (p = 0.007), primary schoolteachers (p = 0.004) and Hindus (p = 0.001) displayed significantly adequate levels of knowledge compared to their respective counterpart. Likewise, based on attitude subjects possessing postgraduation (p = 0.001) and middle schoolteachers (p = 0.009) had significant good attitude scores. Significant linear correlation was observed knowledge with class teacher (r = 0.136, P = 0.03) and religion (r = 0.208, P = 0.001) whereas attitude with qualification (r = 0.165, P = 0.008) and class teacher (r = 0.206, P = 0.001) which are positive predictors. Moreover, knowledge had a significant positive correlation with attitude (r = 1.000, P = 0.000). Conclusion: Primary care physicians partnering network with schoolteachers having adequate knowledge and good attitude acts as a workforce to support cervical cancer screening and human papillomavirus vaccination.

4.
J Pharm Bioallied Sci ; 14(Suppl 1): S1030-S1032, 2022 Jul.
Article in English | MEDLINE | ID: mdl-36110812

ABSTRACT

Rehabilitation of distal extension cases is one of the common challenges in dentistry as fabrication of fixed prosthesis is impossible. For the prosthetic rehabilitation of distal extension, implant-supported prosthesis, cast partial denture, and precision attachment prosthesis can be used. Precision attachment helps in the distribution of masticatory forces, minimizes trauma to abutments and soft tissues, improves the esthetics, and retains proprioception and thus better comfort to the patient. This case report presents the fabrication of precision attachment to retain maxillary and mandibular partial dentures.

5.
J Infect Dis ; 224(12 Suppl 2): S876-S882, 2021 12 20.
Article in English | MEDLINE | ID: mdl-34550361

ABSTRACT

Genomics-driven molecular epidemiology of pathogenic bacteria has largely been carried out through functionally neutral/inert sequences, mostly entailing polymorphic gene loci or repetitive tracts. However, it is very important to harness phenotypically relevant markers to assign a valid functional epidemiological context to tracking of pathogens. These should include microbial acumen to acquire multiple drug resistance (MDR), their physiological coordinates with reference to clinical or community-level dynamics of incidence/transmission, and their response or refractoriness to the activated immune system. We propose that multidimensional and multicentric approaches, based on diverse data integration coupled with comparative genomics and functional molecular infection epidemiology, would likely be successful in tracking the emergence and spread of MDR pathogens and thereby guiding the global infection control strategies in a highly informed manner.


Subject(s)
Anti-Bacterial Agents/pharmacology , Bacteria/drug effects , Bacteria/genetics , Drug Resistance, Multiple, Bacterial/genetics , Bacteria/isolation & purification , Bangladesh , Drug Resistance, Multiple, Bacterial/drug effects , Evolution, Molecular , Genetic Variation , Genome, Bacterial , Genomics/methods , Genotype , India , Infection Control , Microbial Sensitivity Tests , Molecular Epidemiology , Phylogeny , Whole Genome Sequencing/methods
6.
mBio ; 12(1)2021 03 02.
Article in English | MEDLINE | ID: mdl-33653937

ABSTRACT

The genotoxin colibactin is a secondary metabolite produced by the polyketide synthase (pks) island harbored by extraintestinal pathogenic E. coli (ExPEC) and other members of the Enterobacteriaceae that has been increasingly reported to have critical implications in human health. The present study entails a high-throughput whole-genome comparison and phylogenetic analysis of such pathogenic E. coli isolates to gain insights into the patterns of distribution, horizontal transmission, and evolution of the island. For the current study, 23 pks-positive ExPEC genomes were newly sequenced, and their virulome and resistome profiles indicated a preponderance of virulence encoding genes and a reduced number of genes for antimicrobial resistance. In addition, 4,090 E. coli genomes from the public domain were also analyzed for large-scale screening for pks-positive genomes, out of which a total of 530 pks-positive genomes were studied to understand the subtype-based distribution pattern(s). The pks island showed a significant association with the B2 phylogroup (82.2%) and a high prevalence in sequence type 73 (ST73; n = 179) and ST95 (n = 110) and the O6:H1 (n = 110) serotype. Maximum-likelihood (ML) phylogeny of the core genome and intergenic regions (IGRs) of the ST95 model data set, which was selected because it had both pks-positive and pks-negative genomes, displayed clustering in relation to their carriage of the pks island. Prevalence patterns of genes encoding RM systems in the pks-positive and pks-negative genomes were also analyzed to determine their potential role in pks island acquisition and the maintenance capability of the genomes. Further, the maximum-likelihood phylogeny based on the core genome and pks island sequences from 247 genomes with an intact pks island demonstrated horizontal gene transfer of the island across sequence types and serotypes, with few exceptions. This study vitally contributes to understanding of the lineages and subtypes that have a higher propensity to harbor the pks island-encoded genotoxin with possible clinical implications.IMPORTANCE Extraintestinal pathologies caused by highly virulent strains of E. coli amount to clinical implications with high morbidity and mortality rates. Pathogenic E. coli strains are evolving with the horizontal acquisition of mobile genetic elements, including pathogenicity islands such as the pks island, which produces the genotoxin colibactin, resulting in severe clinical outcomes, including colorectal cancer progression. The current study encompasses high-throughput comparative genomics and phylogenetic analyses to address the questions pertaining to the acquisition and evolution pattern of the genomic island in different E. coli subtypes. It is crucial to gain insights into the distribution, transfer, and maintenance of pathogenic islands, as they harbor multiple virulence genes involved in pathogenesis and clinical implications of the infection.


Subject(s)
Enteropathogenic Escherichia coli/genetics , Escherichia coli Infections/microbiology , Evolution, Molecular , Genome, Bacterial , Genomic Islands , Genomics , Computational Biology/methods , DNA, Intergenic , Enteropathogenic Escherichia coli/classification , Enteropathogenic Escherichia coli/pathogenicity , Escherichia coli Infections/epidemiology , Genome-Wide Association Study , Phenotype , Phylogeny , Prevalence , Virulence/genetics , Virulence Factors/genetics
7.
mBio ; 13(1): e0379621, 2021 02 22.
Article in English | MEDLINE | ID: mdl-35164570

ABSTRACT

Escherichia coli, a ubiquitous commensal/pathogenic member from the Enterobacteriaceae family, accounts for high infection burden, morbidity, and mortality throughout the world. With emerging multidrug resistance (MDR) on a massive scale, E. coli has been listed as one of the Global Antimicrobial Resistance and Use Surveillance System (GLASS) priority pathogens. Understanding the resistance mechanisms and underlying genomic features appears to be of utmost importance to tackle further spread of these multidrug-resistant superbugs. While a few of the globally prevalent sequence types (STs) of E. coli, such as ST131, ST69, ST405, and ST648, have been previously reported to be highly virulent and harboring MDR, there is no clarity if certain ST lineages have a greater propensity to acquire MDR. In this study, large-scale comparative genomics of a total of 5,653 E. coli genomes from 19 ST lineages revealed ST-wide prevalence patterns of genomic features, such as antimicrobial resistance (AMR)-encoding genes/mutations, virulence genes, integrons, and transposons. Interpretation of the importance of these features using a Random Forest Classifier trained with 11,988 genomic features from whole-genome sequence data identified ST-specific or phylogroup-specific signature proteins mostly belonging to different protein superfamilies, including the toxin-antitoxin systems. Our study provides a comprehensive understanding of a myriad of genomic features, ST-specific proteins, and resistance mechanisms entailing different lineages of E. coli at the level of genomes; this could be of significant downstream importance in understanding the mechanisms of AMR, in clinical discovery, in epidemiology, and in devising control strategies. IMPORTANCE With the leap in whole-genome data being generated, the application of relevant methods to mine biologically significant information from microbial genomes is of utmost importance to public health genomics. Machine-learning methods have been used not only to mine, curate, or classify the data but also to identify the relevant features that could be linked to a particular class/target. This is perhaps one of the pioneering studies that has attempted to classify a large repertoire of E. coli genome data sets (5,653 genomes) belonging to 19 different STs (including well-studied as well as understudied STs) using machine learning approaches. Important features identified by these approaches have revealed ST-specific signature proteins, which could be further studied to predict possible associations with the phenotypic profiles, thereby providing a better understanding of virulence and the resistance mechanisms among different clonal lineages of E. coli.


Subject(s)
Escherichia coli Infections , Escherichia coli , Humans , Escherichia coli/genetics , Virulence/genetics , Anti-Bacterial Agents/pharmacology , Escherichia coli Infections/epidemiology , Virulence Factors/genetics , Drug Resistance, Multiple, Bacterial/genetics , Drug Resistance, Bacterial/genetics , Informatics , Machine Learning , Phylogeny
8.
Front Microbiol ; 10: 2766, 2019.
Article in English | MEDLINE | ID: mdl-31849903

ABSTRACT

Extended-spectrum ß-lactamases (ESBLs) form the most important resistance determinants prevalent worldwide. Data on ESBL-producing Escherichia coli from poultry and livestock are scarce in India. We present data on the functional and genomic characterization of ESBL-producing E. coli obtained from poultry in India. The whole genome sequences of 28 ESBL-producing E. coli were analyzed comprising of 12 broiler chicken E. coli isolates, 11 free-range chicken E. coli isolates, and 5 human extraintestinal pathogenic E. coli. All of the 28 ESBL-producing E. coli isolates were tested for antibiotic susceptibilities, in vitro conjugation, and virulence-associated phenotypic characteristics. A total of 13 sequence types were identified from the poultry E. coli, which included globally successful sequence types such as ST117 (9%), ST131 (4.3%), and ST10 (4.3%). The most common ESBL gene detected in poultry E. coli genomes was bla CTX-M-15 (17%). Also, FIB (73%) and FII (73%) were the most common plasmid replicons identified. Conjugation experiments demonstrated 54 (7/13), 30 (3/10), and 40% (2/5) of broiler, free-range, and human ExPEC E. coli to be able to transfer their ESBL genes, respectively. The in vitro virulence-associated phenotypic tests revealed the broiler, free-range, and human ExPEC isolates to be comparable in biofilm formation, resistance to serum bactericidal activity, adherence, and invasion capabilities. Our overall results showed prevalence of virulence phenotypes among the diverse ESBL-producing E. coli from poultry; while certain E. coli clones from broiler-poultry may indeed have the potential to cause infection in humans.

9.
Front Microbiol ; 9: 2631, 2018.
Article in English | MEDLINE | ID: mdl-30498477

ABSTRACT

Colibactin, a genotoxin, encoded by the pks pathogenicity island of Escherichia coli belonging to the B2 phylogroup has been reported as a determinant of bacterial pathogenicity. The present study was carried out to detect the pks pathogenicity island in extraintestinal pathogenic E. coli (ExPEC) isolated from a tertiary hospital in Pune, India. Of 462 isolates analyzed, the pks genomic island was detected in 35 (7.6%) isolates, which predominantly belonged to pathogenic phylogroup B2 (97%), and harbored virulence genes such as fimH, sfaD/E, and usp. Biofilm formation assay revealed 21 of the 35 pks-carrying isolates to be strong (SBF > 1.0), 10 isolates to be moderate (SBF = 0.5-1.0), and 4 as weak (SBF < 0.5) biofilm formers. All of the pks-carrying isolates proved resistant against bactericidal activity of human serum. Assays carried out to detect antimicrobial susceptibility revealed 11% of these isolates to be multidrug resistant, 37% producing ESBL and 25% were positive for bla CTX-M-15. The observed prevalence of multidrug resistance and colibactin producing characteristics among pathogenic E. coli belonging to phylogenetic group B2 advocate urgent need for broader surveillance in order to understand and prevent transmission of these ExPEC in community and hospital settings.

10.
Front Microbiol ; 8: 2120, 2017.
Article in English | MEDLINE | ID: mdl-29180984

ABSTRACT

Multidrug-resistant Escherichia coli infections are a growing public health concern. This study analyzed the possibility of contamination of commercial poultry meat (broiler and free-range) with pathogenic and or multi-resistant E. coli in retail chain poultry meat markets in India. We analyzed 168 E. coli isolates from broiler and free-range retail poultry (meat/ceca) sampled over a wide geographical area, for their antimicrobial sensitivity, phylogenetic groupings, virulence determinants, extended-spectrum-ß-lactamase (ESBL) genotypes, fingerprinting by Enterobacterial Repetitive Intergenic Consensus (ERIC) PCR and genetic relatedness to human pathogenic E. coli using whole genome sequencing (WGS). The prevalence rates of ESBL producing E. coli among broiler chicken were: meat 46%; ceca 40%. Whereas, those for free range chicken were: meat 15%; ceca 30%. E. coli from broiler and free-range chicken exhibited varied prevalence rates for multi-drug resistance (meat 68%; ceca 64% and meat 8%; ceca 26%, respectively) and extraintestinal pathogenic E. coli (ExPEC) contamination (5 and 0%, respectively). WGS analysis confirmed two globally emergent human pathogenic lineages of E. coli, namely the ST131 (H30-Rx subclone) and ST117 among our poultry E. coli isolates. These results suggest that commercial poultry meat is not only an indirect public health risk by being a possible carrier of non-pathogenic multi-drug resistant (MDR)-E. coli, but could as well be the carrier of human E. coli pathotypes. Further, the free-range chicken appears to carry low risk of contamination with antimicrobial resistant and extraintestinal pathogenic E. coli (ExPEC). Overall, these observations reinforce the understanding that poultry meat in the retail chain could possibly be contaminated by MDR and/or pathogenic E. coli.

11.
mBio ; 8(5)2017 10 24.
Article in English | MEDLINE | ID: mdl-29066550

ABSTRACT

Escherichia coli sequence type 131 (ST131), a pandemic clone responsible for the high incidence of extraintestinal pathogenic E. coli (ExPEC) infections, has been known widely for its contribution to the worldwide dissemination of multidrug resistance. Although other ExPEC-associated and extended-spectrum-ß-lactamase (ESBL)-producing E. coli clones, such as ST38, ST405, and ST648 have been studied widely, no comparative genomic data with respect to other genotypes exist for ST131. In this study, comparative genomic analysis was performed for 99 ST131 E. coli strains with 40 genomes from three other STs, including ST38 (n = 12), ST405 (n = 10), and ST648 (n = 18), and functional studies were performed on five in-house strains corresponding to the four STs. Phylogenomic analysis results from this study corroborated with the sequence type-specific clonality. Results from the genome-wide resistance profiling confirmed that all strains were inherently multidrug resistant. ST131 genomes showed unique virulence profiles, and analysis of mobile genetic elements and their associated methyltransferases (MTases) has revealed that several of them were missing from the majority of the non-ST131 strains. Despite the fact that non-ST131 strains lacked few essential genes belonging to the serum resistome, the in-house strains representing all four STs demonstrated similar resistance levels to serum antibactericidal activity. Core genome analysis data revealed that non-ST131 strains usually lacked several ST131-defined genomic coordinates, and a significant number of genes were missing from the core of the ST131 genomes. Data from this study reinforce adaptive diversification of E. coli strains belonging to the ST131 lineage and provide new insights into the molecular mechanisms underlying clonal diversification of the ST131 lineage.IMPORTANCEE. coli, particularly the ST131 extraintestinal pathogenic E. coli (ExPEC) lineage, is an important cause of community- and hospital-acquired infections, such as urinary tract infections, surgical site infections, bloodstream infections, and sepsis. The treatment of infections caused by ExPEC has become very challenging due to the emergence of resistance to the first-line as well as the last-resort antibiotics. This study analyzes E. coli ST131 against three other important and globally distributed ExPEC lineages (ST38, ST405, and ST648) that also produced extended-spectrum ß-lactamase (ESBL). This is perhaps the first study that employs the high-throughput whole-genome sequence-based approach to compare and study the genomic features of these four ExPEC lineages in relation to their functional properties. Findings from this study highlight the differences in the genomic coordinates of ST131 with respect to the other STs considered here. Results from this comparative genomics study can help in advancing the understanding of ST131 evolution and also offer a framework towards future developments in pathogen identification and targeted therapeutics to prevent diseases caused by this pandemic E. coli ST131 clone.


Subject(s)
Escherichia coli Infections/microbiology , Escherichia coli/genetics , Extraintestinal Pathogenic Escherichia coli/genetics , Genome, Bacterial , Anti-Bacterial Agents/pharmacology , Comparative Genomic Hybridization , Cross Infection/microbiology , Drug Resistance, Multiple, Bacterial/genetics , Evolution, Molecular , Extraintestinal Pathogenic Escherichia coli/classification , Extraintestinal Pathogenic Escherichia coli/isolation & purification , Genomics/methods , Genotype , High-Throughput Nucleotide Sequencing/methods , Humans , Microbial Sensitivity Tests , Multilocus Sequence Typing , Virulence/genetics , Virulence Factors/genetics , beta-Lactamases/genetics
12.
mBio ; 8(4)2017 08 15.
Article in English | MEDLINE | ID: mdl-28811343

ABSTRACT

Escherichia coli, an intestinal Gram-negative bacterium, has been shown to be associated with a variety of diseases in addition to intestinal infections, such as urinary tract infections (UTIs), meningitis in neonates, septicemia, skin and soft tissue infections (SSTIs), and colisepticemia. Thus, for nonintestinal infections, it is categorized as extraintestinal pathogenic E. coli (ExPEC). It is also an opportunistic pathogen, causing cross infections, notably as an agent of zoonotic diseases. However, comparative genomic data providing functional and genetic coordinates for ExPEC strains associated with these different types of infections have not proven conclusive. In the study reported here, ExPEC E. coli isolated from SSTIs was characterized, including virulence and drug resistance profiles, and compared with isolates from patients suffering either pyelonephritis or septicemia. Results revealed that the majority of the isolates belonged to two pathogenic phylogroups, B2 and D. Approximately 67% of the isolates were multidrug resistant (MDR), with 85% producing extended-spectrum beta-lactamase (ESBL) and 6% producing metallo-beta-lactamase (MBL). The blaCTX-M-15 genotype was observed in at least 70% of the E. coli isolates in each category, conferring resistance to an extended range of beta-lactam antibiotics. Whole-genome sequencing and comparative genomics of the ExPEC isolates revealed that two of the four isolates from SSTIs, NA633 and NA643, belong to pandemic sequence type ST131, whereas functional characteristics of three of the ExPEC pathotypes revealed that they had equal capabilities to form biofilm and were resistant to human serum. Overall, the isolates from a variety of ExPEC infections demonstrated similar resistomes and virulomes and did not display any disease-specific functional or genetic coordinates.IMPORTANCE Infections caused by extraintestinal pathogenic E. coli (ExPEC) are of global concern as they result in significant costs to health care facilities management. The recent emergence of a multidrug-resistant pandemic clone, Escherichia coli ST131, is of primary concern as a global threat. In developing countries, such as India, skin and soft tissue infections (SSTIs) associated with E. coli are marginally addressed. In this study, we employed both genomic analysis and phenotypic assays to determine relationships, if any, among the ExPEC pathotypes. Similarity between antibiotic resistance and virulence profiles was observed, ST131 isolates from SSTIs were reported, and genomic similarities among strains isolated from different disease conditions were detected. This study provides functional molecular infection epidemiology insight into SSTI-associated E. coli compared with ExPEC pathotypes.


Subject(s)
Escherichia coli Infections/microbiology , Escherichia coli/genetics , Escherichia coli/isolation & purification , Extraintestinal Pathogenic Escherichia coli/genetics , Skin Diseases, Bacterial/microbiology , Soft Tissue Infections/microbiology , Anti-Bacterial Agents/pharmacology , Biofilms , Drug Resistance, Multiple, Bacterial/genetics , Escherichia coli/drug effects , Escherichia coli/pathogenicity , Genes, Bacterial , Genomics , Genotype , Humans , India/epidemiology , Phenotype , Phylogeny , Pyelonephritis/microbiology , Sepsis/microbiology , Sequence Analysis, DNA , Skin/microbiology , Virulence Factors , beta-Lactamases/genetics
13.
Appl Environ Microbiol ; 83(1)2017 01 01.
Article in English | MEDLINE | ID: mdl-27815276

ABSTRACT

Some life-threatening, foodborne, and zoonotic infections are transmitted through poultry birds. Inappropriate and indiscriminate use of antimicrobials in the livestock industry has led to an increased prevalence of multidrug-resistant bacteria with epidemic potential. Here, we present a functional molecular epidemiological analysis entailing the phenotypic and whole-genome sequence-based characterization of 11 H. pullorum isolates from broiler and free-range chickens sampled from retail wet markets in Hyderabad City, India. Antimicrobial susceptibility tests revealed all of the isolates to be resistant to multiple antibiotic classes such as fluoroquinolones, cephalosporins, sulfonamides, and macrolides. The isolates were also found to be extended-spectrum ß-lactamase producers and were even resistant to clavulanic acid. Whole-genome sequencing and comparative genomic analysis of these isolates revealed the presence of five or six well-characterized antimicrobial resistance genes, including those encoding a resistance-nodulation-division efflux pump(s). Phylogenetic analysis combined with pan-genome analysis revealed a remarkable degree of genetic diversity among the isolates from free-range chickens; in contrast, a high degree of genetic similarity was observed among broiler chicken isolates. Comparative genomic analysis of all publicly available H. pullorum genomes, including our isolates (n = 16), together with the genomes of 17 other Helicobacter species, revealed a high number (8,560) of H. pullorum-specific protein-encoding genes, with an average of 535 such genes per isolate. In silico virulence screening identified 182 important virulence genes and also revealed high strain-specific gene content in isolates from free-range chickens (average, 34) compared to broiler chicken isolates. A significant prevalence of prophages (ranging from 1 to 9) and a significant presence of genomic islands (0 to 4) were observed in free-range and broiler chicken isolates. Taken together, these observations provide significant baseline data for functional molecular infection epidemiology of nonpyloric Helicobacter species such as H. pullorum by unraveling their evolution in chickens and their possible zoonotic transmission to humans. IMPORTANCE: Globally, the poultry industry is expanding with an ever-growing consumer base for chicken meat. Given this, food-associated transmission of multidrug-resistant bacteria represents an important health care issue. Our study involves a critical baseline approach directed at genome sequence-based epidemiology and transmission dynamics of H. pullorum, a poultry pathogen having established zoonotic potential. We believe our studies would facilitate the development of surveillance systems that ensure the safety of food for humans and guide public health policies related to the use of antibiotics in animal feed in countries such as India. We sequenced 11 new genomes of H. pullorum as a part of this study. These genomes would provide much value in addition to the ongoing comparative genomic studies of helicobacters.


Subject(s)
Chickens/microbiology , DNA, Bacterial/genetics , Drug Resistance, Multiple, Bacterial , Genome, Bacterial , Helicobacter Infections/veterinary , Helicobacter/genetics , Poultry Diseases/microbiology , Animals , Anti-Bacterial Agents/pharmacology , Cephalosporins/pharmacology , Fluoroquinolones/pharmacology , Food Microbiology , Genomic Islands , Helicobacter/drug effects , Helicobacter/isolation & purification , Helicobacter Infections/epidemiology , Helicobacter Infections/microbiology , High-Throughput Nucleotide Sequencing , Humans , India/epidemiology , Microbial Sensitivity Tests , Molecular Epidemiology , Phylogeny , Poultry Diseases/epidemiology , Prophages/genetics , Prophages/isolation & purification , beta-Lactamases/biosynthesis , beta-Lactamases/genetics
14.
Antimicrob Agents Chemother ; 60(11): 6795-6805, 2016 11.
Article in English | MEDLINE | ID: mdl-27600040

ABSTRACT

The global dissemination and increasing incidence of carbapenem-resistant, Gram-negative organisms have resulted in acute public health concerns. Here, we present a retrospective multicenter study on molecular characterization of metallo-ß-lactamase (MBL)-producing clinical Escherichia coli isolates recovered from extraintestinal infections in two hospitals in Pune, India. We screened a large sample size of 510 E. coli isolates for MBL production wherein we profiled their molecular determinants, antimicrobial resistance phenotypes, functional virulence properties, genomic features, and transmission dynamics. Approximately 8% of these isolates were MBL producers, the majority of which were of the NDM-1 (69%) type, followed by NDM-5 (19%), NDM-4 (5.5%), and NDM-7 (5.5%). MBL producers were resistant to all antibiotics tested except for colistin, fosfomycin, and chloramphenicol, which were effective to various extents. Plasmids were found to be an effective means of dissemination of NDM genes and other resistance traits. All MBL producers adhered to and invaded bladder epithelial (T24) cells and demonstrated significant serum resistance. Genomic analysis of MBL-producing E. coli isolates revealed higher resistance but a moderate virulence gene repertoire. A subset of NDM-1-positive E. coli isolates was identified as dominant sequence type 101 (ST101) while two strains belonging to ST167 and ST405 harbored NDM-5. A majority of MBL-producing E. coli strains revealed unique genotypes, suggesting that they were clonally unrelated. Overall, the coexistence of virulence and carbapenem resistance in clinical E. coli isolates is of serious concern. Moreover, the emergence of NDM-1 among the globally dominant E. coli ST101 isolates warrants stringent surveillance and control measures.


Subject(s)
Drug Resistance, Multiple, Bacterial/genetics , Extraintestinal Pathogenic Escherichia coli/genetics , Extraintestinal Pathogenic Escherichia coli/metabolism , beta-Lactamases/metabolism , Escherichia coli Infections/microbiology , Extraintestinal Pathogenic Escherichia coli/pathogenicity , Genetic Variation , Genome, Bacterial , Humans , India , Microbial Sensitivity Tests , Molecular Epidemiology , Plasmids/genetics , beta-Lactamases/genetics
15.
J Clin Diagn Res ; 10(5): ZE13-7, 2016 May.
Article in English | MEDLINE | ID: mdl-27437378

ABSTRACT

Tobacco use is a major preventable cause of premature death and disease, currently leading to over five million deaths each year worldwide. Smoking or chewing tobacco can seriously affect general, as well as oral health. Oral health professionals play an important role in promoting tobacco free-lifestyles. They should counsel their patients not to smoke; and reinforce the anti-tobacco message and refer the patients to smoking cessation services. Dentists are in a unique position to educate and motivate patients concerning the hazards of tobacco to their oral and systemic health, and to provide intervention programs as a part of routine patient care. Tobacco cessation is necessary to reduce morbidity and mortality related to tobacco use. Strategies for tobacco cessation involves 5 A's and 5 R's approach, quit lines and pharmacotherapy. Additionally, tobacco cessation programs should be conducted at community, state and national levels. Various policies should be employed for better tobacco control. Governments should implement the tobacco control measures to reduce the prevalence of tobacco use and exposure to tobacco smoke. In addition, there should be availability of leaflets, brochures, continuing patient education materials regarding tobacco cessation.

16.
PLoS One ; 11(6): e0155459, 2016.
Article in English | MEDLINE | ID: mdl-27248146

ABSTRACT

A wide variety of genome sequencing platforms have emerged in the recent past. High-throughput platforms like Illumina and 454 are essentially adaptations of the shotgun approach generating millions of fragmented single or paired sequencing reads. To reconstruct whole genomes, the reads have to be assembled into contigs, which often require further downstream processing. The contigs can be directly ordered according to a reference, scaffolded based on paired read information, or assembled using a combination of the two approaches. While the reference-based approach appears to mask strain-specific information, scaffolding based on paired-end information suffers when repetitive elements longer than the size of the sequencing reads are present in the genome. Sequencing technologies that produce long reads can solve the problems associated with repetitive elements but are not necessarily easily available to researchers. The most common high-throughput technology currently used is the Illumina short read platform. To improve upon the shortcomings associated with the construction of draft genomes with Illumina paired-end sequencing, we developed Contig-Layout-Authenticator (CLA). The CLA pipeline can scaffold reference-sorted contigs based on paired reads, resulting in better assembled genomes. Moreover, CLA also hints at probable misassemblies and contaminations, for the users to cross-check before constructing the consensus draft. The CLA pipeline was designed and trained extensively on various bacterial genome datasets for the ordering and scaffolding of large repetitive contigs. The tool has been validated and compared favorably with other widely-used scaffolding and ordering tools using both simulated and real sequence datasets. CLA is a user friendly tool that requires a single command line input to generate ordered scaffolds.


Subject(s)
Genomics , Molecular Epidemiology
17.
3 Biotech ; 6(1): 35, 2016 Jun.
Article in English | MEDLINE | ID: mdl-28330105

ABSTRACT

Acne vulgaris (acne) is a chronic inflammatory disease prevalent among adolescents and adults, with significant psychological effects. The aetiology of acne is multifactorial. Several pathophysiological associations have been identified in which Propionibacterium acnes plays a major role. This bacteria primarily affects areas containing oil glands including the face, back and trunk, where it causes the formation of seborrhoea and inflammatory lesions. The treatment methods currently in place have side effects. A novel alternative method with no side effects is hence required. In this study, we report the synthesis of an exopolysaccharide (EPS)-producing bacterial-based nanoparticle as a stable biocompatible material for drug delivery. We then evaluated the effectiveness of EPS-based nanoparticle cream against P. acnes. Our results demonstrate that EPS nanoparticles have great potential as a safe and effective topical treatment for acne vulgaris and other associated infections.

18.
Antimicrob Agents Chemother ; 59(10): 6087-95, 2015 Oct.
Article in English | MEDLINE | ID: mdl-26195517

ABSTRACT

Escherichia coli sequence type 131 (ST131) is a pandemic clone associated with multidrug-resistant, extraintestinal infections, attributable to the presence of the CTX-M-15 extended-spectrum ß-lactamase gene and mutations entailing fluoroquinolone resistance. Studies on subclones within E. coli ST131 are critically required for targeting and implementation of successful control efforts. Our study comprehensively analyzed the genomic and functional attributes of the H30-Rx subclonal strains NA097 and NA114, belonging to the ST131 lineage. We carried out whole-genome sequencing, comparative analysis, phenotypic virulence assays, and profiling of the antibacterial responses of THP1 cells infected with these subclones. Phylogenomic analysis suggested that the strains were clonal in nature and confined entirely to a single clade. Comparative genomic analysis revealed that the virulence and resistance repertoires were comparable among the H30-Rx ST131 strains except for the commensal ST131 strain SE15. Similarly, seven phage-specific regions were found to be strongly associated with the H30-Rx strains but were largely absent in the genome of SE15. Phenotypic analysis confirmed the virulence and resistance similarities between the two strains. However, NA097 was found to be more robust than NA114 in terms of virulence gene carriage (dra operon), invasion ability (P < 0.05), and antimicrobial resistance (streptomycin resistance). RT(2) gene expression profiling revealed generic upregulation of key proinflammatory responses in THP1 cells, irrespective of ST131 lineage status. In conclusion, our study provides comprehensive, genome-inferred insights into the biology and immunological properties of ST131 strains and suggests clonal diversification of genomic and phenotypic features within the H30-Rx subclone of E. coli ST131.


Subject(s)
Escherichia coli/enzymology , beta-Lactamases/metabolism , Cell Line , Drug Resistance, Multiple, Bacterial/genetics , Escherichia coli/drug effects , Escherichia coli/genetics , Humans , Virulence/genetics , beta-Lactamases/genetics
19.
Nucleic Acids Res ; 43(1): 324-35, 2015 Jan.
Article in English | MEDLINE | ID: mdl-25452339

ABSTRACT

The discordant prevalence of Helicobacter pylori and its related diseases, for a long time, fostered certain enigmatic situations observed in the countries of the southern world. Variation in H. pylori infection rates and disease outcomes among different populations in multi-ethnic Malaysia provides a unique opportunity to understand dynamics of host-pathogen interaction and genome evolution. In this study, we extensively analyzed and compared genomes of 27 Malaysian H. pylori isolates and identified three major phylogeographic lineages: hspEastAsia, hpEurope and hpSouthIndia. The analysis of the virulence genes within the core genome, however, revealed a comparable pathogenic potential of the strains. In addition, we identified four genes limited to strains of East-Asian lineage. Our analyses identified a few strain-specific genes encoding restriction modification systems and outlined 311 core genes possibly under differential evolutionary constraints, among the strains representing different ethnic groups. The cagA and vacA genes also showed variations in accordance with the host genetic background of the strains. Moreover, restriction modification genes were found to be significantly enriched in East-Asian strains. An understanding of these variations in the genome content would provide significant insights into various adaptive and host modulation strategies harnessed by H. pylori to effectively persist in a host-specific manner.


Subject(s)
Genome, Bacterial , Helicobacter pylori/genetics , DNA Restriction-Modification Enzymes/genetics , Evolution, Molecular , Genes, Bacterial , Genomics , Helicobacter pylori/classification , Helicobacter pylori/isolation & purification , Helicobacter pylori/pathogenicity , Humans , Malaysia , Phylogeny , Phylogeography , Virulence
20.
Sci Rep ; 4: 7457, 2014 Dec 12.
Article in English | MEDLINE | ID: mdl-25504040

ABSTRACT

Typhoid fever poses significant burden on healthcare systems in Southeast Asia and other endemic countries. Several epidemiological and genomic studies have attributed pseudogenisation to be the major driving force for the evolution of Salmonella Typhi although its real potential remains elusive. In the present study, we analyzed genomes of S. Typhi from different parts of Southeast Asia and Oceania, comprising of isolates from outbreak, sporadic and carrier cases. The genomes showed high genetic relatedness with limited opportunity for gene acquisition as evident from pan-genome structure. Given that pseudogenisation is an active process in S. Typhi, we further investigated core and pan-genome profiles of functional and pseudogenes separately. We observed a decline in core functional gene content and a significant increase in accessory pseudogene content. Upon functional classification, genes encoding metabolic functions formed a major constituent of pseudogenes as well as core functional gene clusters with SNPs. Further, an in-depth analysis of accessory pseudogene content revealed the existence of heterogeneous complements of functional and pseudogenes among the strains. In addition, these polymorphic genes were also enriched in metabolism related functions. Thus, the study highlights the existence of heterogeneous strains in a population with varying metabolic potential and that S. Typhi possibly resorts to metabolic fine tuning for its adaptation.


Subject(s)
Salmonella typhi/genetics , Typhoid Fever/microbiology , Asia, Southeastern/epidemiology , Cluster Analysis , Endemic Diseases , Genome, Bacterial , Humans , Interspersed Repetitive Sequences , Phylogeny , Polymorphism, Single Nucleotide , Typhoid Fever/epidemiology
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