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ABSTRACT Currently, whole-genome sequencing (WGS) data have not shown strong concordance with Escherichia coli susceptibility profiles to the commonly used β-lactam/β-lactamase inhibitor (BL/BLI) combinations: ampicillin-sulbactam (SAM), amoxicillin-clavulanate (AMC), and piperacillin-tazobactam (TZP). Progressive resistance to these BL/BLIs in the absence of cephalosporin resistance, also known as extended-spectrum resistance to BL/BLI (ESRI), has been suggested to primarily result from increased copy numbers of bla TEM variants, which is not routinely assessed in WGS data. We sought to determine whether addition of gene amplification could improve genotype-phenotype associations through WGS analysis of 147 E. coli bacteremia isolates with increasing categories of BL/BLI non-susceptibility ranging from ampicillin (AMP) susceptibility to being fully resistant to all three BL/BLIs. Consistent with a key role of bla TEM in ESRI, 112/134 strains (84%) with at least ampicillin non-susceptibility encoded bla TEM. Evidence of bla TEM amplification (i.e., bla TEM gene copy number estimates > 2×) was present in 40/112 (36%) strains. There were positive correlations between bla TEM copy numbers with minimum inhibitory concentrations of AMC and TZP (P < 0.05) but not for SAM (P = 0.09). The diversity of β-lactam resistance mechanisms, including non-ceftriaxone hydrolyzing bla CTX-M variants, bla OXA-1, and ampC and bla TEM strong promoter mutations, was greater in AMC- and TZP-non-susceptible strains but rarely observed within SAM- and AMP-non-susceptible isolates. Our study indicates that comprehensive analysis of WGS data, including β-lactamase-encoding gene amplification, can help categorize E. coli with AMC or TZP non-susceptibility but that discerning the transition from SAM susceptibility to SAM non-susceptibility using genetic data requires further refinement. IMPORTANCE The increased feasibility of whole-genome sequencing has generated significant interest in using such molecular diagnostic approaches to characterize difficult-to-treat, antimicrobial-resistant (AMR) infections. Nevertheless, there are current limitations in the accurate prediction of AMR phenotypes based on existing AMR gene database approaches, which primarily correlate a phenotype with the presence/absence of a single AMR gene. Our study utilized a large cohort of cephalosporin-susceptible Escherichia coli bacteremia samples to determine how increasing the dosage of narrow-spectrum β-lactamase-encoding genes in conjunction with other diverse β-lactam/β-lactamase inhibitor (BL/BLI) genetic determinants contributes to progressively more severe BL/BLI phenotypes. We were able to characterize the complexity of the genetic mechanisms underlying progressive BL/BLI resistance including the critical role of β-lactamase encoding gene amplification. For the diverse array of AMR phenotypes with complex mechanisms involving multiple genomic factors, our study provides an example of how composite risk scores may improve understanding of AMR genotype/phenotype correlations.

Interferon alpha (IFNα) gene therapy is emerging as a new treatment option for patients with non-muscle invasive bladder cancer (NMIBC). Adenoviral vectors expressing IFNα have shown clinical efficacy treating bacillus Calmette-Guerin (BCG)-unresponsive bladder cancer (BLCA). However, transient transgene expression and adenoviral immunogenicity may limit therapeutic activity. Lentiviral vectors can achieve stable transgene expression and are less immunogenic. In this study, we evaluated lentiviral vectors expressing murine IFNα (LV-IFNα) and demonstrate IFNα expression by transduced murine BLCA cell lines, bladder urothelium, and within the urine following intravesical instillation. Murine BLCA cell lines (MB49 and UPPL1541) were sensitive to IFN-mediated cell death after LV-IFNα, whereas BBN975 was inherently resistant. Upregulation of interleukin-6 (IL-6) predicted sensitivity to IFN-mediated cell death mediated by caspase signaling, which when inhibited abrogated IFN-mediated cell killing. Intravesical therapy with LV-IFNα/Syn3 in a syngeneic BLCA model significantly improved survival, and molecular analysis of treated tumors revealed upregulation of apoptotic and immune-cell-mediated death pathways. In particular, biomarker discovery analysis identified three clinically actionable targets, PD-L1, epidermal growth factor receptor (EGFR), and ALDHA1A, in murine tumors treated with LV-IFNα/Syn3. Our findings warrant the comparison of adenoviral and LV-IFNα and the study of novel combination strategies with IFNα gene therapy for the BLCA treatment.

ABSTRACT Extended-spectrum cephalosporin-resistant Escherichia coli (ESC-R-Ec) is an urgent public health threat with sequence type clonal complex 131 (STc131), phylogroup B2 strains being particularly concerning as the dominant cause of ESC-R-Ec infections. To address the paucity of recent ESC-R-Ec molecular epidemiology data in the United States, we used whole-genome sequencing (WGS) to fully characterize a large cohort of invasive ESC-R-Ec at a tertiary care cancer center in Houston, Texas, collected from 2016 to 2020. During the study time frame, there were 1,154 index E. coli bloodstream infections (BSIs) of which 389 (33.7%) were ESC-R-Ec. Using time series analyses, we identified a temporal dynamic of ESC-R-Ec distinct from ESC-susceptible E. coli (ESC-S-Ec), with cases peaking in the last 6 months of the calendar year. WGS of 297 ESC-R-Ec strains revealed that while STc131 strains accounted for ~45% of total BSIs, the proportion of STc131 strains remained stable across the study time frame with infection peaks driven by genetically heterogeneous ESC-R-Ec clonal complexes. blaCTX-M variants accounted for most β-lactamases conferring the ESC-R phenotype (89%; 220/248 index ESC-R-Ec), and amplification of blaCTX-M genes was widely detected in ESC-R-Ec strains, particularly in carbapenem non-susceptible, recurrent BSI strains. BlaCTX-M-55 was significantly enriched within phylogroup A strains, and we identified blaCTX-M-55 plasmid-to-chromosome transmission occurring across non-B2 strains. Our data provide important information regarding the current molecular epidemiology of invasive ESC-R-Ec infections at a large tertiary care cancer center and provide novel insights into the genetic basis of observed temporal variability for these clinically important pathogens. IMPORTANCE Given that E. coli is the leading cause of worldwide ESC-R Enterobacterales infections, we sought to assess the current molecular epidemiology of ESC-R-Ec using a WGS analysis of many BSIs over a 5-year period. We identified fluctuating temporal dynamics of ESC-R-Ec infections, which have also recently been identified in other geographical regions such as Israel. Our WGS data allowed us to visualize the stable nature of STc131 over the study period and demonstrate a limited but genetically diverse group of ESC-R-Ec clonal complexes are detected during infection peaks. Additionally, we provide a widespread assessment of β-lactamase gene copy number in ESC-R-Ec infections and delineate mechanisms by which such amplifications are achieved in a diverse array of ESC-R-Ec strains. These data suggest that serious ESC-R-Ec infections are driven by a diverse array of strains in our cohort and impacted by environmental factors suggesting that community-based monitoring could inform novel preventative measures.

ABSTRACT Group A streptococcal (GAS) strains causing severe, invasive infections often have mutations in the control of virulence two-component regulatory system (CovRS) which represses capsule production, and high-level capsule production is considered critical to the GAS hypervirulent phenotype. Additionally, based on studies in emm1 GAS, hyperencapsulation is thought to limit transmission of CovRS-mutated strains by reducing GAS adherence to mucosal surfaces. It has recently been identified that about 30% of invasive GAS strains lacks capsule, but there are limited data regarding the impact of CovS inactivation in such acapsular strains. Using publicly available complete genomes (n = 2,455) of invasive GAS strains, we identified similar rates of CovRS inactivation and limited evidence for transmission of CovRS-mutated isolates for both encapsulated and acapsular emm types. Relative to encapsulated GAS, CovS transcriptomes of the prevalent acapsular emm types emm28, emm87, and emm89 revealed unique impacts such as increased transcript levels of genes in the emm/mga region along with decreased transcript levels of pilus operon-encoding genes and the streptokinase-encoding gene ska. CovS inactivation in emm87 and emm89 strains, but not emm28, increased GAS survival in human blood. Moreover, CovS inactivation in acapsular GAS reduced adherence to host epithelial cells. These data suggest that the hypervirulence induced by CovS inactivation in acapsular GAS follows distinct pathways from the better studied encapsulated strains and that factors other than hyperencapsulation may account for the lack of transmission of CovRS-mutated strains. IMPORTANCE Devastating infections due to group A streptococci (GAS) tend to occur sporadically and are often caused by strains that contain mutations in the control of virulence regulatory system (CovRS). In well-studied emm1 GAS, the increased production of capsule induced by CovRS mutation is considered key to both hypervirulence and limited transmissibility by interfering with proteins that mediate attachment to eukaryotic cells. Herein, we show that the rates of covRS mutations and genetic clustering of CovRS-mutated isolates are independent of capsule status. Moreover, we found that CovS inactivation in multiple acapsular GAS emm types results in dramatically altered transcript levels of a diverse array of cell-surface protein-encoding genes and a unique transcriptome relative to encapsulated GAS. These data provide new insights into how a major human pathogen achieves hypervirulence and indicate that factors other than hyperencapsulation likely account for the sporadic nature of the severe GAS disease.

Introduction: Treatment of mood disorders like Major Depressive Disorder (MDD) and anxiety etc., includes longterm use of antidepressants which alleviate the symptoms with proven efficacy and safety. Metabolic syndrome is a cluster of disorder which includes body weight gain, abdominal obesity, hypertriglyceridaemia, hypertension, and hyperglycaemia either individually or collectively. The link between metabolic adverse effects of antidepressants usage requires further elaboration. Aim: To evaluate the metabolic adverse effects of antidepressant drugs among the patients with mood disorders and also to compare with healthy controls. Materials and Methods: This case-control study was conducted in the Department of Pharmacology and Department of Psychiatry at a tertiary care teaching hospital, Puducherry, India from January 2018 to June 2018. A total of 66 participants following the inclusion criteria, were divided into two groups- group A: 33 age and sex matched healthy subjects were enrolled as control group and group B: 33 patients diagnosed to have MDD, anxiety and other mood disorders were the drug treated group. Metabolic profile was screened by body weight, Body Mass Index (BMI), Waist Circumference (WC), Fasting Blood Sugar (FBS) and lipid profile. Independent Student’s t-test was used to compare the lipid profile among groups and One way Analysis of Variance (ANOVA) followed by Dunnet’s t test was used to compare demographic data, lipid profile. Results: The mean age of the study participants was 42.0±13.0 years and 41.3±14.9 years in group A and group B respectively. In present study, male 38 (57.6%) outnumbered females 28 (42.4%). BMI in the groups A and B was 27.0±3.0 (kg/m2) and 29.4±0.9 (kg/m2) respectively (p

The image retrieval is the process of retrieving the relevant images to the query image with minimal searching time in internet. The problem of the conventional Content-Based Image Retrieval (CBIR) system is that they produce retrieval results for either colour images or grey scale images alone. Moreover, the CBIR system is more complex which consumes more time period for producing the significant retrieval results. These problems are overcome through the proposed methodologies stated in this work. In this paper, the General Image (GI) and Medical Image (MI) are retrieved using deep learning architecture. The proposed system is designed with feature computation module, Retrieval Convolutional Neural Network (RETCNN) module, and Distance computation algorithm. The distance computation algorithm is used to compute the distances between the query image and the images in the datasets and produces the retrieval results. The average precision and recall for the proposed RETCNN-based CBIRS is 98.98% and 99.15% respectively for GI category, and the average precision and recall for the proposed RETCNN-based CBIRS are 99.04% and 98.89% respectively for MI category. The significance of these experimental results is used to produce the higher image retrieval rate of the proposed system. [ABSTRACT FROM AUTHOR]

The supplementary function of organic manure in conjunction with chemical fertilizers plays a vital role in maintaining soil health, thereby potentially enhancing rice yield. A field trial was conducted in 2020 during the rice cultivation season in the kharif period at a farmer's field in Alwanneri village, Nanguneri Taluk, Tirunelveli district, Tamil Nadu. The study was designed following a Randomized Block Design (RBD) with seven treatments, three replications to assess various organic manures such as Farm Yard Manure (FYM), Vermicompost (VC), and Vegetable waste compost (VWC) at different combination and dosage levels of application (4.5 t ha-1,11.5 t ha-1, 17.5 t ha-1) in comparison to a control plot without any manure amendment. The study focused on the impact of plant spacing on rice variety TKM 9, analysing plant growth and yield. Seedlings age under 25 days were transplanted with 30x 20cm spacing for six treatment and control plot. Data on plant height, Number of tillers and leaf width were collected from 7 sampling plants in each plot. Results indicated significant effects of planting density and seedling age on plant height, number of tillers and grain yield. Soil samples were collected from random areas covering the entire area within each plot at (0-30cm) depth at before harvest and after harvest it is used for XRD soil morphology analysis. [ABSTRACT FROM AUTHOR]