Antimicrobial resistance (AMR) is a global threat driven mainly by horizontal gene transfer (HGT) mechanisms through mobile genetic elements (MGEs) including integrons. The variable region (VR) of an ...integron can acquire or excise gene cassettes (GCs) that confer resistance to antibiotics based on the selection pressure. Escherichia coli plays a significant role in the genetic transfer of resistance determinants to other Gram-negative bacteria. Current study is aimed to detect and compare integron-mediated resistance in clinical isolates of E. coli. Unique isolates of E. coli from urine or blood cultures were studied for their antimicrobial resistance patterns and integrons were detected using polymerase chain reaction assays followed by Sanger sequencing of GCs.
During the study period, a total of 470 E. coli isolates were obtained, 361 (76.8%) from urinary and 109 (23.1%) from bacteremic sources. Class 1 integrons were detected in 66 (18.2%) and 26 (23.8%) isolates respectively. Urinary isolates of E. coli harbouring Class 1 integrons demonstrated significantly higher rates of resistance (p < 0.05) for most antibiotics (12/16, 75%) compared to integron negative isolates. Although not statistically significant, similar differences were observed in bacteremic isolates. Among the urinary isolates, 27 (40.9%) had a VR, in which the most common GC array detected was DfrA17-AadA5 (n = 14), followed by DfrA5 (n = 4) and DfrA12 (n = 3). Among bacteremic isolates, only 4 (15.3%) had a VR, all of which were carrying DfrA17. The detected GC array correlated with the respective isolates' phenotypic resistance patterns.
We found a strong correlation between integron positivity and trimethoprim resistance among E. coli from urinary sources. Although higher rates of resistance were observed in bacteremic isolates, they mostly carried empty integrons.
Hepatitis E virus (HEV) usually causes self-limiting acute hepatitis, but the disease can become chronic in immunocompromised individuals. HEV infection in pregnant women is reported to cause up to ...30% mortality, especially in the third trimester. Additionally, extrahepatic manifestations like neuronal and renal diseases and pancreatitis are also reported during the course of HEV infection. The mechanism of HEV pathogenesis remains poorly understood. Innate immunity is the first line of defense triggered within minutes to hours after the first pathogenic insult. Growing evidence based on reverse genetics systems, in vitro cell culture models, and representative studies in animal models including non-human primates, has implicated the role of the host’s innate immune response during HEV infection. HEV persists in presence of interferons (IFNs) plausibly by evading cellular antiviral defense. This review summarizes our current understanding of recognizing HEV-associated molecular patterns by host cell Pattern Recognition Receptors (PRRs) in eliciting innate immune response during HEV infection as well as mechanisms of virus-mediated immune evasion.
The Gram-negative soil dwelling bacterium Burkholderia pseudomallei is the etiological agent of melioidosis. The disease is endemic in most parts of Southeast Asia and northern Australia. Over last ...few years, there has been an increase in number of melioidosis cases from India; however the disease epidemiology is less clearly understood. Multi-locus sequence typing (MLST) is a powerful genotypic method used to characterize the genetic diversity of B. Pseudomallei both within and across the geographic regions.
In this study, MLST analysis was performed on 64 B. pseudomallei clinical isolates. These isolates were obtained between 2008-2014 from southwestern coastal region of India. Broad population patterns of Indian B. pseudomallei isolates in context with isolates of Southeast Asia or global collection was determined using in silico phylogenetic tools.
A total of 32 Sequence types (STs) were reported among these isolates of which 17 STs (53%) were found to be novel. ST1368 was found as group founder and the most predominant genotype (n = 11, 17%). Most of the B. pseudomallei isolates reported in this study (or other Indian isolates available in MLST database) clustered in one major group suggesting clonality in Indian isolates; however, there were a few outliers. When analyzed by measure of genetic differentiation (FST) and other phylogenetic tools (e.g. PHYLOViZ), Indian STs were found closer to Southeast Asian isolates than Australian isolates. The phylogenetic analysis further revealed that within Asian clade, Indian isolates grouped more closely with isolates from Sri Lanka, Vietnam, Bangladesh and Thailand.
Overall, the results of this study suggest that the Indian B. pseudomallei isolates are closely related with lesser heterogeneity among them and cluster in one major group suggesting clonality of the isolates. However, it appears that there are a few outliers which are distantly related to the majority of Indian STs. Phylogenetic analysis suggest that Indian isolates are closely related to isolates from Southeast Asia, particularly from South Asia.
The risk of mortality increases further if the patient has underlying noncommunicable diseases notably diabetes, hypertension, and chronic kidney diseases among others. Since the beginning of 2020, ...Coronavirus Disease 2019 (COVID-19) has been an important differential diagnosis in patients presenting with AFI with or without respiratory complaints 3. Simultaneously, in view of prominent broncho-vascular markings, nasopharyngeal and throat swabs were sent for real-time reverse transcriptase-polymerase chain reaction (rRT-PCR) to rule out infection by Severe Acute Respiratory Syndrome-Associated Coronavirus 2 (SARS-CoV-2). The isolate tested positive by monoclonal antibody-based latex agglutination test (Mahidol University, Bangkok, Thailand), Active Melioidosis detect lateral flow immunoassay (InBios International, Seattle, United States of America) and real-time PCR targeting T3SS1 gene, confirming its identity as B. pseudomallei. The isolate from blood culture was identified as B. pseudomallei by VITEK-2 Compact system, typical reactions on conventional biochemical tests and triple disk test (sensitive to amoxicillin-clavulanate and resistant to gentamicin and polymyxin B).
In 2019, Burkholderia pseudomallei was isolated from the backyard of 2 siblings with melioidosis in Kerala, India. This finding highlights the value of healthcare providers being aware of risk for ...melioidosis in febrile patients, of residents taking precautions when outside, and of increasing environmental surveillance for B. pseudomallei in this region.
Several reports of chloroquine treatment failure and resistance in Plasmodium vivax malaria from Southeast Asian countries have been published. Present study was undertaken to assess the efficacy of ...chloroquine-primaquine (CQ-PQ) combined regimen for the treatment of P. vivax malaria patients who were catered by the selected primary health centres (PHCs) of Udupi taluk, Udupi district, Karnataka, India.
Five PHCs were selected within Udupi taluk based on probability proportional to size. In-vivo therapeutic efficacy assessment of CQ (1500 mg over three days) plus PQ (210 mg over 14 days) regimen was carried out in accordance with the World Health Organization's protocol of 28 days follow-up among microscopically diagnosed monoinfection P. vivax cohort.
In total, 161 participants were recruited in the study of which, 155 (96.3%) participants completed till day 28 follow-up, fully complied with the treatment regimen and showed adequate clinical and parasitological response. Loss to follow up was noted with 5 (3.1%) participants and non-compliance with treatment regimen occurred with one participant (0.6%). Glucose-6-phosphate dehydrogenase deficiency (G6PDd, <30% of normal mean activity) was noted among 5 (3.1%) participants and one of them did develop PQ induced dark-brown urination which subsided after PQ discontinuation. G6PDd patients were treated with PQ 45 mg/week for eight weeks while PQ was discontinued in one case with G6PD 1.4 U/g Hb due to complaint of reddish-brown coloured urine by 48 hours of PQ initiation. Nested polymerase chain reaction test revealed 45 (28%) cases as mixed (vivax and falciparum) malaria.
The CQ-PQ combined regimen remains outstandingly effective to treat uncomplicated P. vivax malaria in Udupi taluk and thus it should continue as first line regimen. For all P. vivax cases, G6PD screening before PQ administration must be mandatory and made available in all PHCs.
Importance of hospital environment in patient-care has been recognized widely in infection prevention and control. Inappropriate antibiotic use led to emergence of resistant strains that are ...difficult to treat with the available antibiotics. Progress in nanotechnology led to enhancement of nanoparticles with physicochemical characteristics and functionality that overcomes the constraints of common antimicrobials. Aim was to investigate effective antimicrobial role of Silver nanoparticle (Ag-NPs) against clinically important bacterial strains and observe effects of varying storage temperatures on Ag-NPs antimicrobial activity. Different concentrations of Ag-NPs were tested against Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa and Acinetobacter baumannii using diffusion method. Zone of inhibition (ZOI) for each organism was directly proportional to concentration of Ag-NPs used. Mean ZOI values at different concentrations were significantly different for all organisms with p-value <0.001 for E. coli, S. aureus, P. aeruginosa and 0.004 for A. baumannii. Variation in storage temperature hardly showed any effects on the antimicrobial property of the Ag-NPs. Scanning electron microscopy (SEM) showed morphological and size variations in Ag-NPs exposed cells when compared to control strains, especially for S. aureus, E. coli and P. aeruginosa. Damaged cell membrane areas can be clearly distinguished in E. coli and P. aeruginosa thus suggesting bacterial membrane disruption. These finding can help design a larger study where Ag-NPs can be used in various medical instruments which are usually kept at room temperatures. Also, outcomes of this study may help in designing proper implants, prosthesis and equipment coated with minimum concentration of nanoparticles that might be considered safe for medical applications.
•Temporal analysis of the daily viral load and cytokine levels in hospitalized dengue patients identified the pattern of cytokine dynamics.•Elevated IL-8, IL-10, IL-6, GM-CSF, MCP-1, IL-13, and IL-4 ...and decreased IL-12, MIP-1β on the third day after symptom onset is predictive of severe dengue.•The imbalanced cytokine signature may inform clinical decision-making in treating severe dengue infections.
The immunopathogenesis of dengue severity is convoluted. The primary objective of the research was to examine the dynamics of cytokine storm and its correlation with disease development in individuals affected by DENV infection. Additionally, the study aimed to discover potential biomarkers that could indicate severe dengue infection and determine the most suitable timeframe for predicting the severity of these biomarkers during the acute stage of dengue infections. We conducted a temporal analysis of the daily viral load and cytokine levels in 60 hospitalized dengue patients until discharge. Our findings reveal a distinct cytokine profile (elevated IL-8, IL-10, IL-6, GM-CSF, MCP-1, IL-13, and IL-4 and decreased IL-12, MIP-1β) on the third day after symptom onset is predictive of severe dengue in secondary dengue infection. The imbalanced cytokine signature may inform clinical decision-making in treating severe dengue infections.
Introduction: Dengue virus (DENV) infection is a significant global public health problem, caused by four antigenically distinct serotypes of DENV, namely, DENV-1, DENV-2, DENV-3, and DENV-4. The ...disease manifestations range from asymptomatic or mild undifferentiated fever to severe diseases such as dengue hemorrhagic fever and dengue shock syndrome. Extensive research has been done on pathogenesis of DENV infection and the factors responsible for its severe manifestations. However, there is no ideal prognostic biomarker available yet. In various studies, it has been observed that DENV nonstructural-1 (NS1) protein plays a crucial role in pathogenesis. DENV NS1 protein acts by various mechanisms such as direct effect on vascular endothelium and activation of alternate complement pathway, which causes the release of inflammatory cytokines, leading to plasma leakage. It has also been observed that DENV NS1 levels correlate with disease severity. Until the present date, no commercial quantitative DENV NS1 ELISA is available for quantifying DENV NS1 levels in patients of DENV infection. Aim: Standardization of quantitative DENV NS1 ELISA. Methods: This study utilizes an already available NS1 ELISA kit and known concentrations of recombinant DENV NS1 protein to standardize quantitative DENV NS1 ELISA to estimate the NS1 concentration in human sera. Conclusion: Commercially available DENV NS1 detection kits can be standardized for quantification of DENV NS1 in human sera and use this data to find the association between NS1 concentration and disease severity.
Nosocomial infections, termed hospital-acquired infections (HAIs), are acquired from a healthcare or hospital setting. HAI is mainly caused by bacteria, such as
,
,
,
spp., Methicillin-resistant
...(MRSA), and many more. Due to growing antibacterial resistance, nanotechnology has paved the way for more potent and sensitive methods of detecting and treating bacterial infections. Nanoparticles have been used with molecular beacons for identifying bactericidal activities, targeting drug delivery, and anti-fouling coatings, etc. This review addresses the looming threat of nosocomial infections, with a focus on the Indian scenario, and major initiatives taken by medical bodies and hospitals in spreading awareness and training. Further, this review focuses on the potential role nanotechnology can play in combating the spread of these infections.
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