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Background: The use of silver is rapidly rising in wound care and silver-containing dressings are widely used along with other antibiotics, particularly β-lactams. Consequently, concerns are being raised regarding the emergence of silver-resistance and cross-resistance to β-lactams. Therefore, this study aimed to determine the phenotypic and genotypic profiles of silver-resistance and extended-spectrum β-lactamases in isolates from chronic wounds., Methods: 317 wound swab specimens were collected from tertiary hospitals of Dhaka city and analysed for the microbial identification. The antibiotic resistance/susceptibility profiles were determined and phenotypes of silver resistant isolates were examined. The presence of silver-resistance ( sil ) genes ( silE, silP, and silS ) and extended-spectrum β-lactamases (ESBL) ( CTX-M-1, NDM-1, KPC, OXA-48, and VIM-1 ) were explored in isolated microorganisms., Results: A total of 501 strains were isolated with Staphylococcus aureus (24%) as the predominant organism. In 29% of the samples, polymicrobial infections were observed. A large proportion of Enterobacterales (59%) was resistant to carbapenems and a significantly high multiple antibiotic-resistance indexes (>0.2) were seen for 53% of organisms (P < 0.001). According to molecular analysis, the most prevalent types of ESBL and sil gene were CTX-M-1 (47%) and silE (42%), respectively. Furthermore, phenotypic silver-nitrate susceptibility testing showed significant minimum-inhibitory-concentration patterns between sil -negative and sil -positive isolates. We further observed co-occurrence of silver-resistance determinants and ESBLs (65%)., Conclusions: Notably, this is the first-time detection of silver-resistance along with its co-detection with ESBLs in Bangladesh. This research highlights the need for selecting appropriate treatment strategies and developing new alternative therapies to minimize microbial infection in wounds., Competing Interests: The author declares that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research reported., (© 2023 The Authors.)

Serological analysis is an integral part of laboratory practice nowadays. The present study was aimed to develop and validate a modified Enzyme linked Immunosorbent Assay (ELISA) for determination of IgG antibody against Hepatitis E Virus (HEV) using dried blood spots (DBS) and corresponding plasma samples. A total of 65 samples (45 HEV patients, 20 healthy controls) were analyzed. DBS and plasma samples demonstrated equivalent optical densities for detecting anti-HEV IgG. A highly significant correlation was observed between plasma and DBS sample absorbances (R 2  = 0.98; p < 0.001) at dilution 1:200, indicating true agreement between the two procedures. The assay exhibited decent linearity and showed no effect of physiological hematocrit on assay performance. Data suggested recommendable promise in using DBS as a suitable alternative to plasma samples to determine HEV IgG antibody evidenced by significant correlation with plasma results. Therefore, identical method for processing DBS specimens including it's proper storage is recommended for implementation of a modified ELISA in different settings., Competing Interests: Declaration of competing interest All authors: No reported conflicts. All authors have submitted the ICMJE Form for Disclosure of Potential Conflicts of Interest. Conflicts that the editors consider relevant to the content of the manuscript have been disclosed., (Copyright © 2021 The Authors. Published by Elsevier Masson SAS.. All rights reserved.)

Objectives: To determine IgG immune responses and hepatitis E virus (HEV) viral load, and to explore the associations with pregnancy., Methods: A total of 121 HEV-infected women (57 pregnant, 64 non-pregnant) were analysed. Quantitative reverse transcription PCR (RT-qPCR) was done for 78 HEV IgM-positive patients to determine viral load, and Sanger sequencing was performed for 62 HEV-RNA-positive patients to confirm genotyping. ELISA was conducted to determine HEV antibody and avidity indices., Results: The HEV genotype was identified as variant 1. Significant negative correlations were observed between log HEV copy number and log hepatitis E virus IgG antibody index in the late acute phase of jaundice for both pregnant women (r = -0.7971, p = 0.0002) and non-pregnant women (r = -0.9117, p = 0.0002). Pregnant women had significantly higher serum log viral copy numbers and lower IgG antibody indices than non-pregnant women in the late acute phase of HEV-induced jaundice (p = 0.0196 and p = 0.0303, respectively). Moreover, pregnant women with acute HEV hepatitis had higher cross-reactive IgG antibodies compared to the non-pregnant women (p = 0.0017). Five patients with HEV hepatitis died, of whom four were pregnant., Conclusions: Pregnancy might be associated with higher viral loads and a lower IgG response in the HEV-induced late acute phase of jaundice., (Copyright © 2021 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

Background: Lung cancer is the leading cancer killer. Early detection will reduce the related deaths. The objective of this study was to identify potential biomarkers for early-stage lung cancer in sputum supernatant., Materials and Methods: Using shotgun proteomics, we detected changes in protein profiles that were associated with lung cancer by analyzing sputum supernatants from 6 patients with early-stage lung cancer and 5 cancer-free controls. Using western blotting, we validated the proteomic results in 22 lung cancer cases and 22 controls. Using enzyme-linked immunosorbent assay (ELISA), we evaluated the diagnostic performance of the biomarker candidates in an independent set of 35 cases and 36 controls., Results: Proteomics identified 8 biomarker candidates for lung cancer. Western blotting validation of the candidates showed that enolase 1 (ENO1) displayed a higher expression level in patients with cancer than in cancer-free individuals (P = .015). ELISA revealed that the assessment of ENO1 expression in sputum supernatant had 58.33% sensitivity and 80.00% specificity in distinguishing patients with stage I lung cancer from cancer-free individuals., Conclusion: The analysis of protein biomarkers in sputum may provide a potential approach for the early detection of lung cancer. Future validation of all the candidates defined by shotgun proteomics in a large cohort study may help develop additional biomarkers that can be added to ENO1 to provide more diagnostic efficacy for lung cancer., (Copyright © 2014 Elsevier Inc. All rights reserved.)

Although it has been hypothesized that autoimmune-like phenomena may play a critical role in the protective immune responses to both human and animal malaria, there are still no evidence-based data to support this view. In this study we demonstrate that the majority of anti-single stranded (ss) DNA autoantibody secreting B cells were confined to B220(+)CD21(+)CD23(-) cells and that these cells expanded significantly in the spleen of C57BL/6 mice infected with Plasmodium yoelii 17X non-lethal (PyNL). To determine the role of ssDNA-binding autoantibody secreting B cell responses in murine malaria, we conjugated generation 6 (poly) amidoamine dendrimer nanoparticles with ssDNA to deplete ssDNA-binding autoreactive B cells in vivo. Our data revealed that 55.5% of mice died after DNA-coated nanoparticle-mediated in vivo depletion of ssDNA-specific autoreactive B cells and subsequent challenge using PyNL. Adoptive transfer of B cells with ssDNA specificity to mice, followed by PyNL infection, caused a later appearance and inhibition of parasitemia. The possible mechanism by which the ssDNA-binding autoantibody secreting B cells is involved in the protection against murine malaria has also been demonstrated., (Copyright © 2012 Elsevier GmbH. All rights reserved.)

Various subsets of T-cell receptor (TCR) γδ⁺ T cells expressing distinct TCR-Vγ chains are found in many different anatomical locations. These TCR γδ⁺ T cells perform multiple functions as an essential part of the immune system. In particular, protection against malaria infection by TCR γδ⁺ T cells is of special interest. In the present study, we confirmed that the Vγ7⁺ γδ T cells, which are an unconventional subset usually localized within the intestine, are recruited to the liver and spleen at the late stage of malaria infection, and contribute to protection against malaria infection via a multifunctional approach in apoptosis inhibitor-deficient mice., (Copyright © 2012 Elsevier Inc. All rights reserved.)

Mice were infected with Plasmodium (P.) yoelii blood-stage parasites. Both the liver and spleen were the sites of inflammation during malarial infection at the beginning of day 7. The major expanding cells were found to be NK1.1(-) intermediate alphabetaTCR (alphabetaTCR(int)) in the liver and spleen, although the population of NK1.1(+) alphabetaTCR(int) cells remained constant or slightly increased. These TCR(int) cells are of extrathymic origin or are generated by an alternative intrathymic pathway and are distinguished from conventional T cells of thymic origin. During malarial infection, the population of conventional T cells did not increase at all. TCR(int) cells purified from the liver of mice which had recovered from P. yoelii infection protected mice from malaria when they were transferred into 6.5-Gy-irradiated mice. Interestingly, the immunity against malaria seemed to disappear as a function of time after recovery, namely, mice which had recovered from malaria 1 year previously again became susceptible to malarial infection. The present results suggest that TCR(int) cells are intimately associated with protection against malarial infection and, therefore, that mice which had recovered from malaria 1 year previously lost such immunity., (Copyright 2001 Academic Press.)