Field evaluation of a simple and rapid diagnostic test, RLDT to detect Shigella and enterotoxigenic E. coli in Indian children

The diagnostic assays currently used to detect Shigella spp. (Shigella) and enterotoxigenic Escherichia coli (ETEC) are complex or elaborate which make them difficult to apply in resource poor settings where these diseases are endemic. The simple and rapid nucleic acid amplification-based assay "Rapid LAMP-based Diagnostic Test (RLDT)" was evaluated to detect Shigella spp (Shigella) and enterotoxigenic Escherichia coli (ETEC) and determine the epidemiology of these pathogens in Kolkata, India. Stool samples (n = 405) from children under five years old with diarrhea seeking care at the hospitals were tested, and 85(21%) and 68(17%) by RLDT, 91(23%) and 58(14%) by quantitative PCR (qPCR) and 35(9%) and 15(4%) by culture, were positive for Shigella and ETEC, respectively. The RLDT showed almost perfect agreement with qPCR, Kappa 0.96 and 0.89; sensitivity 93% and 98%; specificity 100% and 97% for Shigella and ETEC, respectively. While RLDT detected additional 12% Shigella and 13% ETEC than culture, all culture positives for Shigella and ETEC except one each were also positive by the RLDT, sensitivity 97% and 93% respectively. RLDT is a simple, sensitive, and rapid assay that could be implemented with minimum training in the endemic regions to strengthen the disease surveillance system and rapid outbreak detection.

Proteo-metabolomic Dissection of Extracellular Matrix Reveals Alterations in Cell Wall Integrity and Calcium Signaling Governs Wall-Associated Susceptibility during Stem Rot Disease in Jute

The plant surveillance system confers specificity to disease and immune states by activating distinct molecular pathways linked to cellular functionality. The extracellular matrix (ECM), a preformed passive barrier, is dynamically remodeled at sites of interaction with pathogenic microbes. Stem rot, caused by Macrophomina phaseolina, adversely affects fiber production in jute. However, how wall related susceptibility affects the ECM proteome and metabolome remains undetermined in bast fiber crops. Here, stem rot responsive quantitative temporal ECM proteome and metabolome were developed in jute upon M. phaseolina infection. Morpho-histological examination revealed that leaf shredding was accompanied by reactive oxygen species production in patho-stressed jute. Electron microscopy showed disease progression and ECM architecture remodeling due to necrosis in the later phase of fungal attack. Using isobaric tags for relative and absolute quantitative proteomics and liquid chromatography-tandem mass spectrometry, we identified 415 disease-responsive proteins involved in wall integrity, acidification, proteostasis, hydration, and redox homeostasis. The disease-related correlation network identified functional hubs centered on α-galactosidase, pectinesterase, and thaumatin. Gas chromatography-mass spectrometry analysis pointed toward enrichment of disease-responsive metabolites associated with the glutathione pathway, TCA cycle, and cutin, suberin, and wax metabolism. Data demonstrated that wall-degrading enzymes, structural carbohydrates, and calcium signaling govern rot responsive wall-susceptibility. Proteomics data were deposited in Pride (PXD046937; PXD046939).

Validation of a Human Challenge Model Using an LT-Expressing Enterotoxigenic E. coli Strain (LSN03-016011) and Characterization of Potential Amelioration of Disease by an Investigational Oral Vaccine Candidate (VLA1701)

Controlled human infection models are important tools for the evaluation of vaccines against diseases where an appropriate correlate of protection has not been identified. Enterotoxigenic Escherichia coli (ETEC) strain LSN03-016011/A (LSN03) is an LT enterotoxin and CS17-expressing ETEC strain useful for evaluating vaccine candidates targeting LT-expressing strains. We sought to confirm the ability of the LSN03 strain to induce moderate-to-severe diarrhea in a healthy American adult population, as well as the impact of immunization with an investigational cholera/ETEC vaccine (VLA-1701) on disease outcomes. A randomized, double-blinded pilot study was conducted in which participants received two doses of VLA1701 or placebo orally, one week apart; eight days after the second vaccination, 30 participants (15 vaccinees and 15 placebo recipients) were challenged with approximately 5 × 109 colony-forming units of LSN03. The vaccine was well tolerated, with no significant adverse events. The vaccine also induced serum IgA and IgG responses to LT. After challenge, 11 of the placebo recipients (73.3%; 95%CI: 48.0-89.1) and 7 of the VLA1701 recipients (46.7%; 95%CI: 24.8-68.8) had moderate-to-severe diarrhea (p = 0.26), while 14 placebo recipients (93%) and 8 vaccine recipients (53.3%) experienced diarrhea of any severity, resulting in a protective efficacy of 42.9% (p = 0.035). In addition, the vaccine also appeared to provide protection against more severe diarrhea (p = 0.054). Vaccinees also tended to shed lower levels of the LSN03 challenge strain compared to placebo recipients (p = 0.056). In addition, the disease severity score was lower for the vaccinees than for the placebo recipients (p = 0.046). In summary, the LSN03 ETEC challenge strain induced moderate-to-severe diarrhea in 73.3% of placebo recipients. VLA1701 vaccination ameliorated disease severity, as observed by several parameters, including the percentage of participants experiencing diarrhea, as well as stool frequency and ETEC severity scores. These data highlight the potential value of LSN03 as a suitable ETEC challenge strain to evaluate LT-based vaccine targets (NCT03576183).

Impact of Rotaviral Diarrhea on Child Growth in Sub-Saharan Africa and South Asia in the Global Enteric Multicenter Study

Rotavirus is the leading cause of dehydrating diarrhea among children in developing countries. The impact of rotaviral diarrhea on nutritional status is not well understood. We aimed to determine the association between rotavirus-positive moderate-to-severe diarrhea and nutrition in children under 5 years of age. We analyzed data from the Global Enteric Multicenter Study on children 0-59 months old from South Asia and sub-Saharan Africa. The relationships between explanatory variables and outcome variables were assessed using multiple linear regression; the explanatory variable was the presence of rotavirus in the stool sample, and the outcome variables were z scores [length/height-for-age (LAZ/HAZ), weight-for-age (WAZ), and weight-for-length/height (WLZ/WHZ)] at follow-up (∼60 days). The prevalence of rotaviral diarrhea was 17.3% (905/5,219) in South Asia and 19.95% (842/4,220) in sub-Saharan Africa. Rotavirus was associated with higher LAZ/HAZ (β: 0.19; 95% CI: 0.12, 0.26; P <0.001) and WAZ (β: 0.15; 95% CI: 0.79, 0.22; P <0.001) in sub-Saharan Africa and with lower WLZ/WHZ (β coefficient: -0.08; 95% CI: -0.15, -0.009; P = 0.027) in South Asia. Our study indicates that rotaviral diarrhea is positively associated with nutritional status in sub-Saharan Africa and is negatively associated with nutritional status in South Asia. An expedited implementation policy of ongoing preventive and control strategies, including vaccination against rotavirus, is necessary to reduce the burden of rotaviral diarrhea, which may further help to reduce the potential nutritional ramifications.

Epidemiology of enterotoxigenic Escherichia coli and impact on the growth of children in the first two years of life in Lima, Peru

Background

Enterotoxigenic E. coli (ETEC) is a leading cause of diarrheal morbidity and mortality in children, although the data on disease burden, epidemiology, and impact on health at the community level are limited.

Methods

In a longitudinal birth cohort study of 345 children followed until 24 months of age in Lima, Peru, we measured ETEC burden in diarrheal and non-diarrheal samples using quantitative PCR (LT, STh, and STp toxin genes), studied epidemiology and measured anthropometry in children.

Results

About 70% of children suffered from one or more ETEC diarrhea episodes. Overall, the ETEC incidence rate (IR) was 73 per 100 child-years. ETEC infections began early after birth causing 10% (8.9-11.1) ETEC-attributable diarrheal burden at the population level (PAF) in neonates and most of the infections (58%) were attributed to ST-ETEC [PAF 7.9% (1.9-13.5)] and LT + ST-ETEC (29%) of which all the episodes were associated with diarrhea. ETEC infections increased with age, peaking at 17% PAF (4.6-27.7%; p = 0.026) at 21 to 24 months. ST-ETEC was the most prevalent type (IR 32.1) with frequent serial infections in a child. The common colonization factors in ETEC diarrhea cases were CFA/I, CS12, CS21, CS3, and CS6, while in asymptomatic ETEC cases were CS12, CS6 and CS21. Only few (5.7%) children had repeated infections with the same combination of ETEC toxin(s) and CFs, suggested genotype-specific immunity from each infection. For an average ETEC diarrhea episode of 5 days, reductions of 0.060 weight-for-length z-score (0.007 to 0.114; p = 0.027) and 0.061 weight-for-age z-score (0.015 to 0.108; p = 0.009) were noted in the following 30 days.

Conclusion

This study showed that ETEC is a significant pathogen in Peruvian children who experience serial infections with multiple age-specific pathotypes, resulting in transitory growth impairment.

The 2022 Vaccines Against Shigella and Enterotoxigenic Escherichia coli (VASE) Conference: Summary of abstract-based presentations

The global nonprofit organization PATH hosted the third Vaccines Against Shigella and Enterotoxigenic Escherichia coli (VASE) Conference in Washington, DC, on November 29 to December 1, 2022. With a combination of plenary sessions and posters, keynote presentations, and breakout workshops, the 2022 VASE Conference featured key updates on research related to the development of vaccines against neglected diarrheal pathogens including Shigella, enterotoxigenic Escherichia coli (ETEC), Campylobacter, and Salmonella. The presentations and discussions highlighted the significant impact of these diarrheal pathogens, particularly on the health of infants and young children in low- and middle-income countries, reflecting the urgent need for the development and licensure of new enteric vaccines. Oral and poster presentations at the VASE Conference explored a range of topics, including: the global burden and clinical presentation of disease, epidemiology, and the impact of interventions; the assessment of the value of vaccines against enteric pathogens; preclinical evaluations of vaccine candidates and models of enteric diseases; vaccine candidates in clinical trials and human challenge models; host parameters and genomics that predict responses to infection and disease; the application of new omics technologies for characterization of emerging pathogens and host responses; novel adjuvants, vaccine delivery platforms, and immunization strategies; and strategies for combination/co-administered vaccines. The conference agenda also featured ten breakout workshop sessions on topics of importance to the enteric vaccine field, which are summarized separately. This article reviews key points and highlighted research presented in each of the plenary conference sessions and poster presentations at the 2022 VASE Conference.

Combining extracellular matrix proteome and phosphoproteome of chickpea and meta-analysis reveal novel proteoforms and evolutionary significance of clade-specific wall-associated events in plant

Extracellular matrix (ECM) plays central roles in cell architecture, innate defense and cell wall integrity (CWI) signaling. During transition to multicellularity, modular domain structures of ECM proteins and proteoforms have evolved due to continuous adaptation across taxonomic clades under different ecological niche. Although this incredible diversity has to some extent been investigated at protein level, extracellular phosphorylation events and molecular evolution of ECM proteoform families remains unexplored. We developed matrisome proteoform atlas in a grain legume, chickpea and performed meta-analyses of 74 plant matrisomes. MS/MS analysis identified 1,424 proteins and 315 phosphoproteins involved in diverse functions. Cross-species ECM protein network identified proteoforms associated with CWI maintenance system. Phylogenetic characterization of eighteen matrix protein families highlighted the role of taxon-specific paralogs and orthologs. Novel information was acquired on gene expansion and loss, co-divergence, sub functionalization and neofunctionalization during evolution. Modular networks of matrix protein families and hub proteins showed higher diversity across taxonomic clades than among organs. Furthermore, protein families differ in nonsynonymous to synonymous substitution rates. Our study pointed towards the matrix proteoform functionality, sequence divergence variation, interactions between wall remodelers and molecular evolution using a phylogenetic framework. This is the first report on comprehensive matrisome proteoform network illustrating presence of CWI signaling proteins in land plants.

Assessing knowledge gaps and empowering Extension workers in Illinois with information on ticks and tickborne diseases through KAP surveys

Tickborne diseases (TBDs) are increasingly prevalent in Illinois and the Upper Midwest region. People who work in occupations that require time outdoors in agricultural or natural settings, such as some Extension workers, are at risk of tick bites and TBDs. Additionally, Extension workers are often a primary source of information about ticks and TBDs in rural communities. However, there is limited information on the level of awareness about ticks and TBDs in the Extension community. The goals of this study were to sequentially i) determine the baseline awareness of Extension workers in Illinois about ticks and TBDs using a knowledge, attitudes, and practices (KAP) survey tool, ii) provide comprehensive training on ticks and TBDs to this demographic, and iii) measure the uptake of knowledge after the training intervention through a post-training survey. The study period was from June 2022 until May 2023. We received 233 pre-training and 93 paired post-training survey responses. Most survey respondents were Extension volunteers, identified as women, and were over 50 years old. Knowledge about ticks and TBDs varied. We identified several gaps in their current tick awareness, most importantly, in tick prevention measures, tick identification, and TBDs in general. TBD knowledge, attitude, and practice scores all significantly improved after training (p < 0.001), with a mean difference of 10.47, 1.49, and 2.64 points, respectively. Additionally, both Extension professionals (79.2 %) and Extension volunteers (66.7 %) were more likely to feel confident in engaging with their stakeholders on ticks and TBDs after participating in training. Poisson models revealed that higher attitude and practice scores and greater self-reported knowledge were the factors most significantly associated with higher TBD knowledge. We found that greater concern for ticks and TBD (attitudes) and adherence to science-based prevention and management methods (practices) were also associated with higher knowledge scores. To our knowledge, this is the first study in Illinois to capture Extension workers' awareness of ticks and TBDs. The results highlight Extension workers' interest in filling knowledge gaps through learning, and the importance of training Extension workers to disseminate reliable and updated information on ticks and TBDs to their constituents, a critical step in preventing TBDs.

Epidemiology of Enterotoxigenic Escherichia coli among Children and Adults Seeking Care at Hospitals in Two Geographically Distinct Rural Areas in Bangladesh

Enterotoxigenic Escherichia coli (ETEC) infections undeniably continue to have substantial morbidity and mortality in younger children; however, limited data are available on the disease burden of older children and adults and on ETEC epidemiology by geographical location at the subnational level. Facility-based surveillance over the years was established to identify patients with ETEC diarrhea in two geographically distinct areas in rural Bangladesh, Chhatak in the north and Mathbaria in the southern coastal area. ETEC was highly prevalent in both areas, while the proportions, toxin types and colonization factors varied by location, season and age groups. Children < 5 years old and adults between 20 and 60 years old were at the highest risk of ETEC diarrhea which required urgent care. This study underscores the importance of capturing subnational and seasonal variations in ETEC epidemiology. ETEC vaccine developers and public health stakeholders may need to target adults between 20 and 60 years of age in addition to young children as new vaccines currently under development become licensed and introduction begins.

Dehydration-responsive cytoskeleton proteome of rice reveals reprograming of key molecular pathways to mediate metabolic adaptation and cell survival

The plant cytoskeletal proteins play a key role that control cytoskeleton dynamics, contributing to crucial biological processes such as cell wall morphogenesis, stomatal conductance and abscisic acid accumulation in repercussion to water-deficit stress or dehydration. Yet, it is still completely unknown which specific biochemical processes and regulatory mechanisms the cytoskeleton uses to drive dehydration tolerance. To better understand the role of cytoskeleton, we developed the dehydration-responsive cytoskeletal proteome map of a resilient rice cultivar. Initially, four-week-old rice plants were exposed to progressive dehydration, and the magnitude of dehydration-induced compensatory physiological responses was monitored in terms of physicochemical indices. The organelle fractionation in conjunction with label-free quantitative proteome analysis led to the identification of 955 dehydration-responsive cytoskeletal proteins (DRCPs). To our knowledge, this is the first report of a stress-responsive plant cytoskeletal proteome, representing the largest inventory of cytoskeleton and cytoskeleton-associated proteins. The DRCPs were apparently involved in a wide array of intra-cellular molecules transportation, organelles positioning, cytoskeleton organization followed by different metabolic processes including amino acid metabolism. These findings presented open a unique view on global regulation of plant cytoskeletal proteome is intimately linked to cellular metabolic rewiring of adaptive responses, and potentially confer dehydration tolerance, especially in rice, and other crop species, in general.

The Antimicrobial Resistance of Enterotoxigenic Escherichia coli from Diarrheal Patients and the Environment in Two Geographically Distinct Rural Areas in Bangladesh over the Years

Antimicrobial resistance (AMR) is an unprecedented global health challenge, involving the transfer of bacteria and genes between humans and the environment. We simultaneously and longitudinally determined the AMR of enterotoxigenic Escherichia coli (ETEC) strains isolated from diarrheal patients and an aquatic environment over two years from two geographically distinct locations, Coastal Mathbaria and Northern Chhatak in Bangladesh. A total of 60% and 72% of ETEC strains from the patients in Mathbaria and Chhatak, respectively, were multi-drug resistant (MDR) with a high proportion of ETEC resistant to nalidixic acid (80.7%), macrolides (49.1-89.7%), ampicillin (57.9-69%), and trimethoprim/sulfamethoxazole (55.2%). From the surface water, 68.8% and 30% of ETEC were MDR in Mathbaria and Chhatak, respectively, with a high proportion of ETEC strains resistant to macrolides (87.5-100%), ampicillin (50-75%), ceftriaxone (62.5%), and nalidixic acid (40%). Notably, 80-100% of the ETEC strains were susceptible to tetracycline and quinolones (ciprofloxacin and norfloxacin), both in clinical and aquatic ETEC. The AMR varied by the ETEC toxin types. The patterns of excessive or limited consumption of drugs to treat diarrhea over time in Bangladesh were reflected in the ETEC AMR from the patients and the environment. The high prevalence of MDR-ETEC strains in humans and the environment is of concern, which calls for vaccines and other preventative measures against ETEC.

Effects of breastfeeding on children's gut colonization with multidrug-resistant Enterobacterales in peri-urban Lima, Peru

Children living in low-resource settings are frequently gut-colonized with multidrug-resistant bacteria. We explored whether breastfeeding may protect against children's incident gut colonization with extended-spectrum beta-lactamase-producing Escherichia coli (ESBL-Ec) and Klebsiella, Enterobacter, or Citrobacter spp. (ESBL-KEC). We screened 937 monthly stool samples collected from 112 children aged 1-16 months during a 2016-19 prospective cohort study of enteric infections in peri-urban Lima. We used 52,816 daily surveys to examine how exposures to breastfeeding in the 30 days prior to a stool sample were associated with children's risks of incident gut-colonization, controlling for antibiotic use and other covariates. We sequenced 78 ESBL-Ec from 47 children to explore their diversity. Gut-colonization with ESBL-Ec was increasingly prevalent as children aged, approaching 75% by 16 months, while ESBL-KEC prevalence fluctuated between 18% and 36%. Through 6 months of age, exclusively providing human milk in the 30 days prior to a stool sample did not reduce children's risk of incident gut-colonization with ESBL-Ec or ESBL-KEC. From 6 to 16 months of age, every 3 additional days of breastfeeding in the prior 30 days was associated with 6% lower risk of incident ESBL-Ec gut-colonization (95% CI: 0.90, 0.98, p = .003). No effects were observed on incident ESBL-KEC colonization. We detected highly diverse ESBL-Ec among children and few differences between children who were predominantly breastfed (mean age: 4.1 months) versus older children (10.8 months). Continued breastfeeding after 6 months conferred protection against children's incident gut colonization with ESBL-Ec in this setting. Policies supporting continued breastfeeding should be considered in efforts to combat antibiotic resistance.

Contribution of the Rapid LAMP-Based Diagnostic Test (RLDT) to the Evaluation of Enterotoxigenic Escherichia coli (ETEC) and Shigella in Childhood Diarrhea in the Peri-Urban Area of Ouagadougou, Burkina Faso

The estimates of enterotoxigenic Escherichia coli (ETEC) and Shigella burden in developing countries are limited by the lack of rapid, accessible, and sensitive diagnostics and surveillance tools. We used a "Rapid LAMP based Diagnostic Test (RLDT)" to detect ETEC and Shigella in diarrheal and non-diarrheal stool samples from a 12-month longitudinal cohort of children under five years of age in a peri-urban area of Ouagadougou in Burkina Faso (West Africa). To allow comparison with the RLDT-Shigella results, conventional culture methods were used to identify Shigella strains in the stool samples. As conventional culture alone cannot detect ETEC cases, a subset of E. coli-like colonies was tested using conventional PCR to detect ETEC toxins genes. Of the 165 stool samples analyzed for ETEC, 24.9% were positive when using RLDT against 4.2% when using culture followed by PCR. ETEC toxin distribution when using RLDT was STp 17.6% (29/165), LT 11.5% (19/165), and STh 8.5% (14/165). Of the 263 specimens tested for Shigella, 44.8% were positive when using RLDT against 23.2% when using culture. The sensitivity and specificity of the RLDT compared to culture (followed by PCR for ETEC) were 93.44% and 69.8% for Shigella and 83.7% and 77.9% for ETEC, respectively. This study indicates that both Shigella and ETEC are substantially underdiagnosed when using conventional culture and highlights the potential contribution of the new RLDT method to improve enteric disease burden estimation and to guide future efforts to prevent and control bacterial enteric infection and disease.

ARTIFICIAL INTELLIGENCE: CREATING NEW PARADIGMS IN THE MANAGEMENT OF NON-COMMUNICABLE DISEASES

The role of Artificial Intelligence (AI) in medical science is growing immensely. Since AI contains features that can address both preventive and therapeutic aspects of non-communicable diseases (NCDs), it can potentially lessen the massive burden of morbidity and mortality associated with NCDs. AI can help in various ways in NCDs including predicting disease occurrence, monitoring, ensuring treatment and follow-up of patients. Low- and middle-income countries can harness the benefit of AI for the management of chronic diseases and effectively address challenges like manpower shortage, accessibility to health care, etc. However, AI needs to be used responsibly and rationally in NCDs for its maximum benefit.

Field evaluation of a simple and rapid diagnostic test, RLDT to detect Shigella and enterotoxigenic E. coli in Indian children

The diagnostic assays currently used to detect Shigella spp. (Shigella) and enterotoxigenic Escherichia coli (ETEC) are complex or elaborate which make them difficult to apply in resource poor settings where these diseases are endemic. The simple and rapid nucleic acid amplification-based assay "Rapid LAMP-based Diagnostic Test (RLDT)" was evaluated to detect Shigella spp (Shigella) and enterotoxigenic Escherichia coli (ETEC) and determine the epidemiology of these pathogens in Kolkata, India. Stool samples (n = 405) from children under five years old with diarrhea seeking care at the hospitals were tested, and 85(21%) and 68(17%) by RLDT, 91(23%) and 58(14%) by quantitative PCR (qPCR) and 35(9%) and 15(4%) by culture, were positive for Shigella and ETEC, respectively. The RLDT showed almost perfect agreement with qPCR, Kappa 0.96 and 0.89; sensitivity 93% and 98%; specificity 100% and 97% for Shigella and ETEC, respectively. While RLDT detected 12% more Shigella and 13% more ETEC than culture, all culture positives for Shigella and ETEC except one each were also positive by the RLDT, sensitivity 97% and 93% respectively. RLDT is a simple, sensitive, and rapid assay that could be implemented with minimum training in the endemic regions to strengthen the disease surveillance system and rapid outbreak detection.

Differential expression of genes during recovery of Nicotiana tabacum from tomato leaf curl Gujarat virus infection

MAIN CONCLUSION

Nicotiana tabacum exhibits recovery response towards tomato leaf curl Gujarat virus. Transcriptome analysis revealed the differential expression of defense-related genes. Genes encoding for cysteine protease inhibitor, hormonal- and stress-related to DNA repair mechanism are found to be involved in the recovery process. Elucidating the role of host factors in response to viral infection is crucial in understanding the plant host-virus interaction. Begomovirus, a genus in the family Geminiviridae, is reported throughout the globe and is known to cause serious crop diseases. Tomato leaf curl Gujarat virus (ToLCGV) infection in Nicotiana tabacum resulted in initial symptom expression followed by a quick recovery in the systemic leaves. Transcriptome analysis using next-generation sequencing (NGS) revealed a large number of differentially expressed genes both in symptomatic as well as recovered leaves when compared to mock-inoculated plants. The virus infected N. tabacum results in alteration of various metabolic pathways, phytohormone signaling pathway, defense related protein, protease inhibitor, and DNA repair pathway. RT-qPCR results indicated that Germin-like protein subfamily T member 2 (NtGLPST), Cysteine protease inhibitor 1-like (NtCPI), Thaumatin-like protein (NtTLP), Kirola-like (NtKL), and Ethylene-responsive transcription factor ERF109-like (NtERTFL) were down-regulated in symptomatic leaves when compared to recovered leaves of ToLCGV-infected plants. In contrast, the Auxin-responsive protein SAUR71-like (NtARPSL) was found to be differentially down-regulated in recovered leaves when compared to symptomatic leaves and the mock-inoculated plants. Lastly, Histone 2X protein like (NtHH2L) gene was found to be down-regulated, whereas Uncharacterized (NtUNCD) was up-regulated in both symptomatic as well as recovered leaves compared to the mock-inoculated plants. Taken together, the present study suggests potential roles of the differentially expressed genes that might govern tobacco's susceptibility and/or recovery response towards ToLCGV infection.

Fabrication of thin Molybdenum backed target using rolling method

A successful attempt was made to fabricate a thin foil of natural Mo target on a thick Au backing with Indium in between to improve adhesion between the foils. Rolling at elevated temperature was considered to fabricate Mo foil while gold foil was fabricated employing conventional rolling technique. The heating of Mo foil under natural environment lead to the oxidation or carbonization on foil surface which was confirmed through Energy Dispersive X-ray Spectroscopy (EDS) measurements. Indium of thickness ∼86μg/cm² was evaporated on Mo foil to improve adhesion between Mo and Au foils. The characterization of fabricated thin Mo foil was done using the Energy Dispersive X-ray Spectroscopy (EDS) and the Scanning Electron microscope (SEM) techniques. Thickness measurement of the target (Mo-Au) was done using Energy Dispersive X-ray Fluorescence (EDXRF) technique, in the measurements the thickness of the Mo foil and of gold backing are found out to be 1.3 mg/cm² and 9 mg/cm² respectively.

Development of a simple, rapid, and sensitive molecular diagnostic assay for cholera

Cholera continues to inflict high rates of morbidity and mortality. Prompt identification of cholera cases facilitates rapid outbreak responses in the short term while providing reliable surveillance data to guide long-term policies and interventions. Microbiological stool culture, the current recognized gold standard for diagnosing cholera, has significant limitations. Rapid diagnostic tests (RDTs) represent promising alternatives for diagnosing cholera in areas with limited laboratory infrastructure. However, studies conducted with the current cholera RDTs demonstrated wide variations in sensitivity and specificity. To address this gap in the diagnosis of cholera, we developed a simple, rapid, and sensitive diagnostic assay, "Rapid LAMP based Diagnostic Test (RLDT)." With a novel, simple sample preparation method directly from the fecal samples along with lyophilized reaction strips and using established Loop-mediated Isothermal Amplification (LAMP) platform, cholera toxin gene (ctxA) and O1 (O1rfb) gene could be detected in less than an hour. Cholera RLDT assay is cold chain and electricity-free. To avoid any end-user bias, a battery-operated, handheld reader was used to read the RLDT results. The performance specifications of the cholera RLDT assay, including analytical sensitivity and specificity, were evaluated using direct fecal samples, dried fecal samples on filter paper, and environmental water samples spiked with cholera strain. The limit of detection (LOD) was ~104 CFU/gm of stool for both ctxA and O1 genes, corresponding to about 1 CFU of Vibrio cholerae per reaction within 40 minutes. The LOD was 10 bacteria per ml of environmental water when tested with RLDT directly, without enrichment. Being simple, RLDT has the potential to be applied in resource-poor endemic settings for rapid, sensitive, and reliable diagnosis of cholera.

The plant cytoskeleton takes center stage in abiotic stress responses and resilience

Stress resilience behaviours in plants are defensive mechanisms that develop under adverse environmental conditions to promote growth, development and yield. Over the past decades, improving stress resilience, especially in crop species, has been a focus of intense research for global food security and economic growth. Plants have evolved specific mechanisms to sense external stress and transmit information to the cell interior and generate appropriate responses. Plant cytoskeleton, comprising microtubules and actin filaments, takes a center stage in stress-induced signalling pathways, either as a direct target or as a signal transducer. In the past few years, it has become apparent that the function of the plant cytoskeleton and other associated proteins are not merely limited to elementary processes of cell growth and proliferation, but they also function in stress response and resilience. This review summarizes recent advances in the role of plant cytoskeleton and associated proteins in abiotic stress management. We provide a thorough overview of the mechanisms that plant cells employ to withstand different abiotic stimuli such as hypersalinity, dehydration, high temperature and cold, among others. We also discuss the crucial role of the plant cytoskeleton in organellar positioning under the influence of high light intensity.

Wilson's disease - a tricky diagnosis on the acute take

Wilson's disease is a rare genetic disorder that affects copper metabolism in the body, leading to excess copper accumulation in various organs, including the liver and brain. It often presents to both primary and secondary care, with a combination of liver disease and neurological or psychiatric symptoms, but the presentation can be highly variable. Early recognition and treatment of Wilson's disease is important to prevent critical hepatic and neurological complications. In this case report, we describe the presentation of an 18-year-old male university student with a combination of dysphagia, tremors, and slurred speech, which progressed over several months. Through a series of investigations, the patient was diagnosed with Wilson's disease and received appropriate treatment. This report highlights the importance of considering Wilson's disease in patients with a wide range of symptoms and the need for a pragmatic approach to diagnosis, including routine and additional testing as necessary.

Intense chorus waves are the cause of flux-limiting in the heart of the outer radiation belt

Chorus waves play a key role in outer Van Allen electron belt dynamics through cyclotron resonance. Here, we use Van Allen Probes data to reveal a new and distinct population of intense chorus waves excited in the heart of the radiation belt during the main phase of geomagnetic storms. The power of the waves is typically ~ 2-3 orders of magnitude greater than pre-storm levels, and are generated when fluxes of ~ 10-100 keV electrons approach or exceed the Kennel-Petschek limit. These intense chorus waves rapidly scatter electrons into the loss cone, capping the electron flux to a value close to the limit predicted by Kennel and Petschek over 50 years ago. Our results are crucial for understanding the limits to radiation belt fluxes, with accurate models likely requiring the inclusion of this chorus wave-driven flux-limiting process, that is independent of the acceleration mechanism or source responsible for enhancing the flux.

Migrated and Impacted Foreign Body of Retropharyngeal Space: A Case Report

Foreign body upper aerodigestive tract is a common presentation but foreign body migrating into retropharyngeal space is not only uncommon, but its management also differs and is challenging too. Here we present a case of a foreign body migrating into the retropharyngeal space which was removed intraorally. A 28- year old male patient presented with complaints of pain while swallowing following consumption of sausage and pork two days earlier to the onset of symptoms. X-Ray Neck AP and lateral view were done which revealed a thin metallic foreign body at the level of the T4 vertebra. Upper gastrointestinal endoscopy and rigid esophagoscopy were done in which a foreign body was not visualized in the esophageal lumen. NCCT neck was done which gave precise location and was removed intraorally with the patient in Rose position. A repeat x-ray was done on the 5th day which revealed no foreign body, the patient was discharged on the 7th day. Although the upper aerodigestive tract foreign body is common, foreign body migrating to the posterior pharyngeal wall or into the retropharyngeal space is not common and it is difficult to remove a migrated foreign body many cases requiring open procedures, thoracoscopy, thoracotomy.

Incidence of in-hospital all-cause mortality, resource utilization and complications in patients with adult congenital heart disease undergoing TAVR-a national inpatient sample study

Background

The prevalence of congenital heart disease (CHD) in adults in the United States is approximately 1.4 million. (1) With the advancement in diagnostic modalities and advanced treatments, including minimally invasive techniques, the life expectancy of individuals with CHD has greatly improved. (2) As these patients enter the 8th decade of their lives, the risk of calcification and aortic stenosis increases like the population without CHD. Current evidence supports transcatheter aortic valve replacement (TAVR) over surgical aortic valve replacement in individuals with moderate to high surgical risk. (3) Adults with acyanotic CHD (ACHD) with a higher risk for surgical complications are candidates for consideration of TAVR. There are sparse data about the cardiovascular outcome in these patients.

Purpose

With this National inpatient sample (NIS) study, the authors have shown the incidence of in-hospital all-cause mortality, resource utilization, and complications in adult patients with ACHD undergoing TAVR.

Methods

NIS 2016–2018 were utilized to conduct the study. Analyses were performed using STATA, version 16.0. Using appropriate ICD-10-PCS codes, authors identified adult patients with ACHD undergoing TAVR. The primary outcome of the study is to identify the impact of ACHD on all-cause in-hospital mortality and complications. Secondary outcomes of interest were resource utilization.

Results

134,170 patients were identified who had TAVR done between 2016–2018. Patients aged ≤18 years were excluded (N=25). Out of 134,170 patients that underwent TAVR, 1,170 (0.87%) were noted to have ACHD. Using the greedy algorithm, 1,115 matched pairs were generated. The ACHD group had a higher burden of co-morbidities including atrial fibrillation (46.2% vs. 38.8%, p=0.016), pulmonary hypertension (27.4% vs. 17.5%, p&lt;0.001), metabolic syndrome (1.3% vs. 0.3%, p=0.005), peripheral vascular disease (29.5% vs. 24.1%, p=0.049), alcohol use disorder (3.0% vs. 1.3%, p=0.018), coagulation disorder (22.7% vs. 12.8%, p&lt;0.001), drug abuse (1.3% vs. 0.4%, p=0.043), liver disease (7.3% vs. 3.1%, p&lt;0.001) and electrolyte disturbances (20.5% vs. 14.9%, p=0.017). We also noted a possible trend towards higher complication odds (cardiac complications such as the need for pericardial drain or cardiac implantable electronic device and cardiac arrest) in patients with ACHD undergoing TAVR without statistical significance based on multivariate analysis. On propensity matching, no difference was found in the incidence of overall cardiac complications between patients with ACHD and patients without ACHD, except STEMI (OR 4.16, 95% CI, 1.08–16.00, p=0.038).

Conclusion(s)

The study points towards the possible safety of pursuing TAVR in ACHD patients provided adequate technical support and operator competency.

Funding Acknowledgement

Type of funding sources: None.

Same-day discharge following transcatheter aortic valve replacement: a propensity-matched analysis from national readmission database

Background

The length of hospital stay following transcatheter aortic valve replacement (TAVR) has decreased in recent years, and next-day discharge strategy is being increasingly adopted in some centers. Whether it is safe to further expedite discharge post-TAVR in selected patients by allowing discharge on the same day as the procedure remains unknown. In addition to potentially decreasing hospitalization costs, it could also limit the inpatient footprint and strain on healthcare resources.

Purpose

The purpose of our study was to compare the 30-day readmission rate in patients receiving TAVR who were discharged the same day (same-day discharge or SDD group) with those who were discharged on a different day (different-day discharge or DDD group). Additionally, we aimed to identify risk factors for readmission after TAVR.

Methods

We used the United States Nationwide Readmission Database to identify all adults who underwent elective TAVR in the years 2015–2019. The primary outcome of this study was all-cause 30-day readmission rate. The secondary outcomes were total hospital costs for the index admission, and risk factors for 30-day readmission. Propensity score matching was conducted to compare the SDD and DDD groups. Independent risk factors of 30-day readmission were identified using multivariate Cox proportional hazards regression analysis of the unmatched cohort.

Results

Of the 196,618 patients who received TAVR (mean age 79.5±8.4 years, 45.0% females), 245 (0.12%) patients were discharged on the same day they received TAVR (SDD group), and the remaining 196,373 were discharged on a different day (DDD group). In the DDD group, the median length of hospital stay was 2 days (interquartile range 1–4 days). A 1:3 propensity score analysis generated a matched cohort including 245 and 889 patients in the SDD and DDD groups, respectively. The 30-day readmission rate was similar between the SDD and DDD groups (11.0% versus 10.8%, hazard ratio [HR] 1.01, 95% confidence interval [CI] 0.59–1.71, p=0.989). Hospitalization costs were significantly lower in the SDD group than the DDD group ($37,811±18,029 versus $49,130±27,007, p&lt;0.001) (see Picture 1). Age, female gender, history of diabetes, chronic kidney disease, chronic pulmonary disease, oxygen use, prior stroke, peripheral vascular disease, anemia, liver disease, and cancer were found to be independent risk factors for 30-day readmission after TAVR (see Picture 2).

Conclusion

In this large nationwide database analysis, patients receiving uncomplicated TAVR who were discharged on the same day as the procedure had a similar all-cause 30-day readmission rate and significantly lower hospital costs compared to those discharged on a different day. These results indicate that same-day discharge after TAVR may be a safe and feasible option in carefully selected patients.

Funding Acknowledgement

Type of funding sources: None.

Suspension cell secretome of the grain legume Lathyrus sativus (grasspea) reveals roles in plant development and defense responses

Plant secretomics has been especially important in understanding the molecular basis of plant development, stress resistance and biomarker discovery. In addition to sharing a similar role in maintaining cell metabolism and biogenesis with the animal secretome, plant-secreted proteins actively participate in signaling events crucial for cellular homeostasis during stress adaptation. However, investigation of the plant secretome remains largely overlooked, particularly in pulse crops, demanding urgent attention. To better understand the complexity of the secretome, we developed a reference map of a stress-resilient orphan legume, Lathyrus sativus (grasspea), which can be utilized as a potential proteomic resource. Secretome analysis of L. sativus led to the identification of 741 nonredundant proteins belonging to a myriad of functional classes, including antimicrobial, antioxidative and redox potential. Computational prediction of the secretome revealed that ∼29% of constituents are predicted to follow unconventional protein secretion (UPS) routes. We conducted additional in planta analysis to determine the localization of two secreted proteins, recognized as cell surface residents. Sequence-based homology comparison revealed that L. sativus shares ∼40% of the constituents reported thus far from in vitro and in planta secretome analysis in model and crop species. Significantly, we identified 571 unique proteins secreted from L. sativus involved in cell-to-cell communication, organ development, kinase-mediated signaling, and stress perception, among other critical roles. Conclusively, the grasspea secretome participates in putative crosstalk between genetic circuits that regulate developmental processes and stress resilience.

Remote working in India during the COVID-19 crisis

India has been reeling from the effects of the COVID-19 pandemic and has enforced a nationwide lockdown to ensure the spread is contained, and the situation is under control. This has paved the way for corporate across the length and breadth of the country to embrace remote working as the only feasible option to continue their business. Earlier, it used to be the IT sector employees and a handful of employees from other industries who had the privilege of working remotely. Now, with remote working becoming the norm, we aim to capture how it has affected people’s working style and if interactions with family at home during work hours affect their work. We also aim to find out whether performance takes a hit due to the absence of co-workers.A questionnaire was filled up by employees working from home that sought out details about their working style, daily routine, interactions with other people (family member or colleague), and their thoughts on the remote working lifestyle. The major factors were measured on a five-point Likert scale.People work for a longer time when working from home, due to distractions caused by interactions with family members or other people and also the absence of colleagues causes problems to be solved at a slower pace. Women work longer hours when compared to men, additionally due to household chores. The absence of colleagues coupled with distractions at home cause people to prefer working from the office rather than from home. This study would help identify what sort of impact remote working has on an employee’s performance and how it can affect the working style.The paper analyses the effect of remote working and the presence of family at home on an employee’s performance.

Field evaluation of a novel, rapid diagnostic assay, and molecular epidemiology of enterotoxigenic E. coli among Zambian children presenting with diarrhea

Background

Enterotoxigenic Escherichia coli (ETEC) is one of the top aetiologic agents of diarrhea in children under the age of 5 in low-middle income countries (LMICs). The lack of point of care diagnostic tools for routine ETEC diagnosis results in limited data regarding the actual burden and epidemiology in the endemic areas. We evaluated performance of the novel Rapid LAMP based Diagnostic Test (RLDT) for detection of ETEC in stool as a point of care diagnostic assay in a resource-limited setting.

Methods

We conducted a cross-sectional study of 324 randomly selected stool samples from children under 5 presenting with moderate to severe diarrhea (MSD). The samples were collected between November 2012 to September 2013 at selected health facilities in Zambia. The RLDT was evaluated by targeting three ETEC toxin genes [heat labile toxin (LT) and heat stable toxins (STh and STp)]. Quantitative PCR was used as the “gold standard” to evaluate the diagnostic sensitivity and specificity of RLDT for detection of ETEC. We additionally described the prevalence and seasonality of ETEC.

Results

The study included 324 participants, 50.6% of which were female. The overall prevalence of ETEC was 19.8% by qPCR and 19.4% by RLDT. The children between 12 to 59 months had the highest prevalence of 22%. The study determined ETEC toxin distribution was LT 28/321(9%), ST 18/321(6%) and LT/ST 16/321(5%). The sensitivity and specificity of the RLDT compared to qPCR using a Ct 35 as the cut-off, were 90.7% and 97.5% for LT, 85.2% and 99.3% for STh and 100% and 99.7% for STp, respectively.

Conclusion

The results of this study suggest that RLDT is sufficiently sensitive and specific and easy to implement in the endemic countries. Being rapid and simple, the RLDT also presents as an attractive tool for point-of-care testing at the health facilities and laboratories in the resource-limited settings.

ETEC is one of the top causes of diarrheal diseases in low and middle income countries. The advancement of molecular diagnosis has made it possible to accurately detect ETEC in endemic areas. However, the complexity, infrastructure and cost implication of these tests has made it a challenge to routinely incorporate them in health facilities in endemic settings. The ETEC RLDT is a simple and cost-effective molecular tool that can be used to screen for ETEC in resource limited settings. Here, we described the performance of the RLDT against a qPCR as the gold standard. Our findings showed that the ETEC RLDT performs comparable to the qPCR and would be a suitable screening tool in health facilities in recourse limited settings.

Use of geographical information systems (GIS) in assessing ecological profile, fish community structure and production of a large reservoir of Himachal Pradesh

The present study demonstrates the spatial analysis and mapping of fish and different measures of environmental parameters and fish diversity of Pong reservoir, Himachal Pradesh, using Kriging spatial interpolation methods for geographical information system mapping. Seasonal data on environmental parameters, potential fish habitat and fish diversity was collected from lentic (dam), lentic (reservoir), transitional and lotic zone of the reservoir.. Important environmental parameters like water temperature, dissolved oxygen, electrical conductivity, water depth and transparency showed variations across the different zones of the reservoir. The sediment of the reservoir was sandy clay loam in nature as per texture analysis. Fish species richness, Shannon index and evenness index showed a similarity of the lotic and lentic (reservoir) zones of the reservoir. Six potential fish breeding grounds were identified in the reservoir indicating high conservation significance. The analysis of data showed a declining trend in fish production from 456.9 tonnes during the decade 1976-1987 to 347.91 tonnes during 2009-2020. The factors like anthropogenic climate change, predation of a stocked fish juvenile by water birds, undersized fish stocking and unscientific management are the probable reasons for the decreasing fish production. The spatial variation pattern of the water spread area, environmental parameters, fish catch and potential fish breeding grounds depicted in the GIS platform can be used as an important information base by the policy makers for fisheries management. The stocking of large size fish as a stocking material and adequate protection of the potential fish breeding grounds are the key advisories for the sustainable enhancement of fisheries as well as conservation.

Driving Influences of the Doppler Flash Observed by SuperDARN HF Radars in Response to Solar Flares

Sudden enhancement in high-frequency absorption is a well-known impact of solar flare-driven Short-Wave Fadeout (SWF). Less understood, is a perturbation of the radio wave frequency as it traverses the ionosphere in the early stages of SWF, also known as the Doppler flash. Investigations have suggested two possible sources that might contribute to it's manifestation: first, enhancements of plasma density in the D-and lower E-regions; second, the lowering of the F-region reflection point. Our recent work investigated a solar flare event using first principles modeling and Super Dual Auroral Radar Network (SuperDARN) HF radar observations and found that change in the F-region refractive index is the primary driver of the Doppler flash. This study analyzes multiple solar flare events observed across different SuperDARN HF radars to determine how flare characteristics, properties of the traveling radio wave, and geophysical conditions impact the Doppler flash. In addition, we use incoherent scatter radar data and first-principles modeling to investigate physical mechanisms that drive the lowering of the F-region reflection points. We found, (a) on average, the change in E- and F-region refractive index is the primary driver of the Doppler flash, (b) solar zenith angle, ray's elevation angle, operating frequency, and location of the solar flare on the solar disk can alter the ionospheric regions of maximum contribution to the Doppler flash, (c) increased ionospheric Hall and Pedersen conductance causes a reduction of the daytime eastward electric field, and consequently reduces the vertical ion-drift in the lower and middle latitude ionosphere, which results in lowering of the F-region ray reflection point.

Elevated 5‐hydroxytryptamine in COVID‐19 Stimulates ANO1 Mediated Cl Secretion in Lung & Intestinal Epithelial Cells

Earlier studies demonstrated that blood 5‐hydroxytryptamine (5‐HT) is elevated in patients with COVID‐19‐associated diarrhea with higher severity of symptoms. We hypothesize that disruption of vectorial Cl transport by 5‐HT may be critical in determining the alveolar flooding and abnormalities in intestinal Cl secretion through stimulation of anoctamin 1(ANO1) Cl channel. Using western blot, immunostaining, and electrophysiology, we characterized the localization of human ANO1 and its stimulation by 5‐HT on Cl secretion in lung and intestinal epithelium. Because calcium‐activated chloride current in human intestinal epithelia remains controversial, we examined the localization of ANO1 in the human terminal ileum and colonic tissue using confocal microscopy. Our results indicated that ANO1 was localized predominantly at the brush‐border membrane and co‐localized with the brush‐border membrane marker villin. ANO1 is not present in goblet cells. The anti‐ANO1 antibody recognized a protein of appropriate size in human colonic tissue. The specificity of the ANO1 antibody was tested by immunoblot analysis of lysates from human colorectal cancer tissues, where it displayed amplified ANO1 protein expression. We next confirmed ANO1‐currents activated by 5‐HT in the Caco‐2 cells by patch‐clamp measurements of whole‐cell current. The application of 100 nM 5‐HT produced a typical outward rectification. CaCCinh‐A01, a specific ANO1 blocker, inhibited the currents. The half‐maximal effective concentration value for the effects of 5‐HT was estimated at 21.8 ± 13.7 nM with a Hill coefficient of 0.89 ± 0.16. These results indicated that 5‐HT evoked calcium‐activated Cl currents through ANO1 channels. ANO1 is expressed in Calu 3 cells. We next confirmed the presence of ANO1 currents activated by 5‐HT in Calu‐3 cells by the Ussing chamber experiments. Serosal addition of 5‐HT produced an immediate and significant increase in I_sc in Calu‐3 cells that was inhibited by the ANO1 selective inhibitor T16Ainh‐A01. Finally, we demonstrate that SARS‐CoV2 infection led to enterochromaffin cell hyperplasia in the intestinal epithelium of Syrian Hamster with a possible elevation of 5‐HT, which could explain the severity of symptoms in COVID‐19 associated diarrheal patients.

In conclusion, SARS‐CoV2 infection resulted in intestinal enterochromaffin cells hyperplasia that could elevate 5‐HT. Elevated 5‐HT activates luminal ANO1 CaCC in the intestinal and lung epithelium by a mechanism that appears to involve the rise of [Ca²⁺]_i. Our data suggest that 5‐HT may be a critical determinant of the COVID‐19 associated diarrhea and flooding of alveoli that have considerable implications for COVID‐19 therapy.

Effect of telephone-monitored home-based cardiac rehabilitation exercise on functional capacity and quality of life in heart failure patients in a lower-middle-income country

Funding Acknowledgements

Type of funding sources: None.

Introduction

Chronic heart failure (CHF) prevails as one of the major cardiovascular diseases in lower-middle-income countries (LMICs) like Bangladesh. Home-Based Cardiac Rehabilitation (HBCR) is a cost-effective method of secondary prevention of chronic heart failure which, if provided, might not only improve the health status of the patients but might also reduce the financial and hospitalization burden on the health care system of these countries. The study aims to assess the scope and benefits of HBCR in such low resource settings.

Purpose

The study evaluates the effect of telephone-monitored HBCR exercise programme in improving the functional capacity and quality of life (QoL) in patients of CHF with reduced ejection fraction due to ischemic heart disease (IHD).

Method

This self-controlled interventional study was conducted from August 2019 to July 2020 at a heart failure clinic, a tertiary healthcare centre in Bangladesh. A total of 115 patients of CHF with ejection fraction &lt;40% and in NYHA class II and III were included in the study according to selection criteria. The functional capacity of the patients was evaluated by NYHA classification and 6-minute walk test. The quality of life of the patients was evaluated by Minnesota Living with Heart Failure Questionnaire (MLHFQ). All patients were advised to perform HBCR exercise as per recommended guideline and were telephone-monitored 2-weekly. After the 3-months study period, the participants were divided into compliant and partial compliant groups based on their adherence to the guideline. Repeat evaluation of patients' condition was carried out. Results were then compared within the groups and data was analyzed through appropriate statistical methods.

Results

Significant improvement of NYHA class (p&lt;0.05), and 6-minute walk test distance (6MWTD) (1102.01±215.90 feet vs 1243.30±217.86 feet; p&lt;0.001) were noticed after the rehabilitation programme. Improvement of total MLHFQ score was also observed (35.53±14 vs 28.22±12.84; p&lt;0.001) at 3-months follow up. The functional capacity and quality of life of the patients in both the compliant and partially compliant groups showed significant improvement after the rehabilitation programme (p&lt;0.001); though no difference was found in the indicators when compared between compliant vs partially compliant groups after rehabilitation except for 6MWTD (1302.86±219.61 feet vs 1230.71±212.284 feet, p&lt;0.001).

Conclusion

From the results, it can be concluded that any amount of routine exercise tends to improve quality of life and symptoms in patients of chronic heart failure with reduced ejection fraction. However, to achieve the best effect in functional capacity and overall health status, the addition of a structured exercise programme like HBCR can be beneficial for proper rehabilitation in low resource settings. Further validation of the results is recommended through randomized control trials in larger study groups.

Monitoring COVID-19 Cases and Vaccination in Indian States and Union Territories Using Unsupervised Machine Learning Algorithm

The worldwide spread of the novel coronavirus originating from Wuhan, China led to an ongoing pandemic as COVID-19. The disease being a contagion transmitted rapidly in India through the people having travel histories to the affected countries, and their contacts that tested positive. Millions of people across all states and union territories (UT) were affected leading to serious respiratory illness and deaths. In the present study, two unsupervised clustering algorithms namely k-means clustering and hierarchical agglomerative clustering are applied on the COVID-19 dataset in order to group the Indian states/UTs based on the pandemic effect and the vaccination program from the period of March, 2020 to early June, 2021. The aim of the study is to observe the plight of each state and UT of India combating the novel coronavirus infection and to monitor their vaccination status. The research study will be helpful to the government and to the frontline workers coping to restrict the transmission of the virus in India. Also, the results of the study will provide a source of information for future research regarding the COVID-19 pandemic in India.

Impact of plasma glucose and duration of type 2 diabetes mellitus on SYNTAX Score II in patients suffering from non ST-elevation myocardial infarction

Aim    The objective was to assess the correlation of fasting plasma glucose (FPG), HbA1c, and the duration of type 2 diabetes mellitus (T2DM) with SYNTAX score (SS) II in patients with non-ST elevation myocardial infarction (NSTEMI).Material and methods    FPG and HbA1C were measured in 398 patients presenting with NSTEMI at admission. SS II was calculated using an online calculator. Patients were stratified according to SS II (≤21.5, 21.5-30.6, and ≥30.6), defined as SS II low, mid, and high, respectively.Results    37.7 % of subjects were diabetic. Correlations of FPG (R=0.402, R2=0.162, p&lt;0.001) and HbA1c (R=0.359, R2=0.129, p&lt;0.001) with SS II were weak in the overall population. Duration of T2DM showed very strong correlation with SS II (R=0.827, R2=0.347). For the prediction of high SS II in the study population, FPG≥98.5 mg / dl demonstrated a sensitivity of 58 % and a specificity of 60 %, and HbA1c ≥6.05 demonstrated a sensitivity of 63 % and a specificity of 69 %. Duration of T2DM (adjusted odds ratio (OR): 1.182; 95 % confidence interval (CI): 1.185-2.773) and FPG (OR: 0.987; 95 % CI: 0.976-0.9959) were significantly associated with high SS II after controlling for other risk factors. Duration of T2DM (Beta=0.439) contributed strongly to variance of SS II, whereas HbA1c (Beta=0.063) contributed weakly.Conclusion    Duration of T2DM is a very important risk factor for severity of coronary artery disease.

Molecular simulation of linear octacosane via a CG10 coarse grain scheme

Following our previous work on the united-atom simulation on octacosane (C₂₈H₅₈) (Dai et al., Phys. Chem. Chem. Phys., 2021, 23, 21262-21271), we developed a coarse grain scheme (CG10), which is able to reproduce the pivotal phase characteristics of octacosane with highly improved computational efficiency. The CG10 octacosane chain was composed of 10 consecutive beads, maintaining the fundamental zigzag chain morphology. When the potential functions were set up and the coefficients were parameterized, our CG10 models yielded solid phase diagrams and transitions during an annealing process. We also detected the melting point by various means: direct observation, bond order, density tracking, and an enthalpy plot. Furthermore, our CG10 successfully reproduced the liquid density with only 2% underestimation, indicating its applicability across the solid and liquid phases. Therefore, with the ability to reproduce critical structure and property characteristics, our CG10 scheme provides an effective means of numerically modelling octacosane with highly improved computational efficiency.

Dissection of grasspea (Lathyrus sativus L.) root exoproteome reveals critical insights and novel proteins

The plant exoproteome is crucial because its constituents greatly influence plant phenotype by regulating physiological characteristics to adapt to environmental stresses. The root exudates constitute a dynamic aspect of plant exoproteome, as its molecular composition ensures a beneficial rhizosphere in a species-specific manner. We investigated the root exoproteome of grasspea, a stress-resilient pulse and identified 2861 non-redundant proteins, belonging to a myriad of functional classes, including root development, rhizosphere augmentation as well as defense functions against soil-borne pathogens. Significantly, we identified 1986 novel exoproteome constituents of grasspea, potentially involved in cell-to-cell communication and root meristem maintenance, among other critical roles. Sequence-based comparison revealed that grasspea shares less than 30 % of its exoproteome with the reports so far from model plants as well as crop species. Further, the exoproteome revealed 65 % proteins to be extracellular in nature and of these, 37 % constituents were predicted to follow unconventional protein secretion (UPS) mode. We validated the UPS for four stress-responsive proteins, which were otherwise predicted to follow classical protein secretion (CPS). Conclusively, we recognized not only the highest number of root exudate proteins, but also pinpointed novel signatures of dicot root exoproteome.

Evaluation of a simple, rapid and field-adapted diagnostic assay for enterotoxigenic E. coli and Shigella

Understanding the global burden of enterotoxigenic E. coli (ETEC) and Shigella diarrhea as well as estimating the cost effectiveness of vaccines to control these two significant pathogens have been hindered by the lack of a diagnostic test that is rapid, simple, sensitive, and can be applied to the endemic countries. We previously developed a simple and rapid assay, Rapid Loop mediated isothermal amplification based Diagnostic Test (RLDT) for the detection of ETEC and Shigella spp. (Shigella). In this study, the RLDT assay was evaluated in comparison with quantitative PCR (qPCR), culture and conventional PCR for the detection of ETEC and Shigella. This validation was performed using previously collected stool samples from endemic countries, from the travelers to the endemic countries, as well as samples from a controlled human infection model study of ETEC. The performance of RLDT from dried stool spots was also validated. RLDT resulted in excellent sensitivity and specificity compared to qPCR (99% and 99.2% respectively) ranging from 92.3 to 100% for the individual toxin genes of ETEC and 100% for Shigella. Culture was less sensitive compared to RLDT. No significant differences were noted in the performance of RLDT using samples from various sources or stool samples from moderate to severe diarrhea or asymptomatic infections. RLDT performed equally well in detection of ETEC and Shigella from the dried stool samples on filter papers. This study established that RLDT is sufficiently sensitive and specific to be used as a simple and rapid diagnostic assay to detect ETEC and Shigella in endemic countries to determine disease burden of these pathogens in the national and subnational levels. This information will be important to guide public health and policy makers to prioritize resources for accelerating the development and introduction of effective preventative and/or treatment interventions against these enteric infections.

Enterotoxigenic E. coli (ETEC) and Shigella spp (Shigella) causes significant global morbidity and mortality, especially in low-and middle-income countries (LMICs). Since culture methods to detect Shigella are not sensitive, and the methods used to detect ETEC have not been feasible outside of specialized, well-equipped laboratories, the true burden of these pathogens at national and sub-national levels are mostly not available. Morbidity and mortality estimates, for these two pathogens are crucial to assess their relative public health importance in LMICs. We developed a simple and rapid diagnostic assay called the RLDT (Rapid Loop-mediated isothermal amplification based Diagnostic Test) for detection of ETEC and Shigella. In this study we evaluated RLDT compared to other currently available assays using previously collected stool samples. Our data showed that the RLDT assay exhibited high sensitivity and specificity for detection of ETEC and Shigella, with its result available within 50 minutes. The sensitivity of RLDT was higher than culture for these pathogens. We conclude that RLDT could be used as a rapid and simple diagnostic test to determine the burden of ETEC and Shigella in LMICs as well as in clinical vaccine trials of these pathogens.

Development of a simple, rapid, and sensitive diagnostic assay for enterotoxigenic E. coli and Shigella spp applicable to endemic countries

Enterotoxigenic E. coli (ETEC) and Shigella spp (Shigella) are complex pathogens. The diagnostic assays currently used to detect these pathogens are elaborate or complicated, which make them difficult to apply in resource poor settings where these diseases are endemic. The culture methods used to detect Shigella are not sensitive, and the methods used to detect ETEC are only available in a few research labs. To address this gap, we developed a rapid and simple diagnostic assay–"Rapid LAMP based Diagnostic Test (RLDT)." The six minutes sample preparation method directly from the fecal samples with lyophilized reaction strips and using established Loop-mediated Isothermal Amplification (LAMP) platform, ETEC [heat labile toxin (LT) and heat stable toxins (STh, and STp) genes] and Shigella (ipaH gene) detection was made simple, rapid (<50 minutes), and inexpensive. This assay is cold chain and electricity free. Moreover, RLDT requires minimal equipment. To avoid any end user’s bias, a battery-operated, handheld reader was used to read the RLDT results. The results can be read as positive/negative or as real time amplification depending on the end user’s need. The performance specifications of the RLDT assay, including analytical sensitivity and specificity, were evaluated using fecal samples spiked with ETEC and Shigella strains. The limit of detection was ~10⁵ CFU/gm of stool for LT, STh, and STp and ~10⁴ CFU/gm of stool for the ipaH gene, which corresponds to about 23 CFU and 1 CFU respectively for ETEC and Shigella per 25uL reaction within 40 minutes. The RLDT assay from stool collection to result is simple, and rapid and at the same time sufficiently sensitive. RLDT has the potential to be applied in resource poor endemic settings for the rapid diagnosis of ETEC and Shigella.

Enterotoxigenic E. coli and Shigella are the leading causes of moderate to severe diarrhea in the low-and middle-income countries (LMICs). A critical constraint to determine the ETEC and Shigella disease burden at the country or sub-national level, is the complex diagnostic methods currently required for detecting these pathogens. These methods are neither sufficiently sensitive nor standardized and are not feasible in the resource poor settings where these infections occur most commonly. We developed a simple and rapid diagnostic assay called "Rapid Loop-mediated isothermal amplification based Diagnostic Test (RLDT)" for the detection of these pathogens in low-resource settings. Using RLDT, ETEC and Shigella were detected directly from the stool, in less than 1 hour with minimal hands-on time. The assay does not require maintaining a cold chain and is electricity-free. Being rapid, simple, and sensitive, RLDT can be scaled up and is appropriate to apply in the LMICs where ETEC and Shigella diarrhea are endemic.

Proteomic dissection of rice cytoskeleton reveals the dominance of microtubule and microfilament proteins, and novel components in the cytoskeleton-bound polysome

The plant cytoskeleton persistently undergoes remodeling to achieve its roles in supporting cell division, differentiation, cell expansion and organelle transport. However, the links between cell metabolism and cytoskeletal networks, particularly how the proteinaceous components execute such processes remain poorly understood. We investigated the cytoskeletal proteome landscape of rice to gain better understanding of such events. Proteins were extracted from highly enriched cytoskeletal fraction of four-week-old rice seedlings, and the purity of the fraction was stringently monitored. A total of 2577 non-redundant proteins were identified using both gel-based and gel-free approaches, which constitutes the most comprehensive dataset, thus far, for plant cytoskeleton. The data set includes both microtubule and microfilament-associated proteins and their binding proteins comprising hypothetical as well as novel cytoskeletal proteins. Further, various in-silico analyses were performed, and the proteins were functionally classified on the basis of their gene ontology. The catalogued proteins were validated through their sequence analysis. Extensive comparative analysis of our dataset with the non-redundant set of cytoskeletal proteins across plant species affirms unique as well as overlapping candidates. Together, these findings unveil new insights of how cytoskeletons undergo dynamic remodeling in rice to drive seedling development processes in rapidly changing in planta environment.

Dehydration-responsive chickpea chloroplast protein, CaPDZ1, confers dehydration tolerance by improving photosynthesis

The screening of a dehydration-responsive chloroplast proteome of chickpea led us to identify and investigate the functional importance of an uncharacterized protein, designated CaPDZ1. In all, we identified 14 CaPDZs, and phylogenetic analysis revealed that these belong to photosynthetic eukaryotes. Sequence analyses of CaPDZs indicated that CaPDZ1 is a unique member, which harbours a TPR domain besides a PDZ domain. The global expression analysis showed that CaPDZs are intimately associated with various stresses such as dehydration and oxidative stress along with certain phytohormone responses. The CaPDZ1-overexpressing chickpea seedlings exhibited distinct phenotypic and molecular responses, particularly increased photosystem (PS) efficiency, ETR and qP that validated its participation in PSII complex assembly and/or repair. The investigation of CaPDZ1 interacting proteins through Y2H library screening and co-IP analysis revealed the interacting partners to be PSII associated CP43, CP47, D1, D2 and STN8. These findings supported the earlier hypothesis regarding the role of direct or indirect involvement of PDZ proteins in PS assembly or repair. Moreover, the GUS-promoter analysis demonstrated the preferential expression of CaPDZ1 specifically in photosynthetic tissues. We classified CaPDZ1 as a dehydration-responsive chloroplast intrinsic protein with multi-fold abundance under dehydration stress, which may participate synergistically with other chloroplast proteins in the maintenance of the photosystem.

Interacting Genetic Lesions of Melanoma in the Tumor Microenvironment: Defining a Viable Therapy

Melanoma is the most aggressive form of skin cancer with an estimated 106,110 newly diagnosed cases in the United States of America in 2021 leading to an approximated 7180 melanoma-induced deaths. Cancer typically arises from an accumulation of somatic mutations and can be associated with mutagenic or carcinogenic exposure. A key characteristic of melanoma is the extensive somatic mutation rate of 16.8 mutations/Mb, which is largely attributed to UV exposure. Bearing the highest mutational load, many of them occur in key driver pathways, most commonly the BRAFV600E in the mitogen-activated protein kinase (MAPK) pathway. This driver mutation is targeted clinically with FDA-approved therapies using small molecule inhibitors of oncogenic BRAFV600E and MEK, which has greatly expanded therapeutic intervention following a melanoma diagnosis. Up until 2011, therapeutic options for metastatic melanoma were limited, and treatment typically fell under the spectrum of surgery, radiotherapy, and chemotherapy.Attributed to the extensive mutation rate, as well as having the highest number of neoepitopes, melanoma is deemed to be extremely immunogenic. However, despite this highly immunogenic nature, melanoma is notorious for inducing an immunosuppressive microenvironment which can be relieved by checkpoint inhibitor therapy. The two molecules currently approved clinically are ipilimumab and nivolumab, which target the molecules CTLA-4 and PD-1, respectively.A plethora of immunomodulatory molecules exist, many with redundant functions. Additionally, these molecules are expressed not only by immune cells but also by tumor cells within the tumor microenvironment. Tumor profiling of these cell surface checkpoint molecules is necessary to optimize a clinical response. The presence of immunomodulatory molecules in melanoma, using data from The Cancer Genome Atlas and validation of expression in two model systems, human melanoma tissues and patient-derived melanoma cells, revealed that the expression levels of B and T lymphocyte attenuator (BTLA), TIM1, and CD226, concurrently with the BRAFV600E mutation status, significantly dictated overall survival in melanoma patients. These molecules, along with herpesvirus entry mediator (HVEM) and CD160, two molecules that are a part of the HVEM/BTLA/CD160 axis, had a higher expression in human melanoma tissues when compared to normal skin melanocytes and have unique roles to play in T cell activation. New links are being uncovered between the expression of immunomodulatory molecules and the BRAFV600E genetic lesion in melanoma. Small molecule inhibitors of the MAPK pathway regulate the surface expression of this multifaceted molecule, making BTLA a promising target for immuno-oncology to be targeted in combination with small molecule inhibitors, potentially alleviating T regulatory cell activation and improving patient prognosis.

The Controlled Human Infection Model for Enterotoxigenic Escherichia coli

The controlled human infection model (CHIM) for enterotoxigenic Escherichia coli (ETEC) has been instrumental in defining ETEC as a causative agent of acute watery diarrhea, providing insights into disease pathogenesis and resistance to illness, and enabling preliminary efficacy evaluations for numerous products including vaccines, immunoprophylactics, and drugs. Over a dozen strains have been evaluated to date, with a spectrum of clinical signs and symptoms that appear to replicate the clinical illness seen with naturally occurring ETEC. Recent advancements in the ETEC CHIM have enhanced the characterization of clinical, immunological, and microbiological outcomes. It is anticipated that omics-based technologies applied to ETEC CHIMs will continue to broaden our understanding of host-pathogen interactions and facilitate the development of primary and secondary prevention strategies.

Effect of thrombocytopenia in patients with infective endocarditis: an insight from the National Inpatient Sample database

Introduction

Infective endocarditis (IE) is one of the feared diseases in septic patients, and incidences are rising due to the intravenous drug abuse epidemic. Sepsis causes an escalation of the platelet destructions leading to thrombocytopenia (1). Few independent hospital-based studies have proposed increase mortality with thrombocytopenia in patients with IE (2–5). We aim to evaluate the significance of thrombocytopenia in IE subjects from the national inpatient sample (NIS) database.

Method

We analyzed the NIS database from Jan-2016 to Dec-2018 using Stata 16.0. NIS is the largest publicly available all-payer inpatient care database in the United States, containing data on more than seven million hospital stays per year. We identified patients with IE with or without thrombocytopenia using ICD-10 codes. The primary outcome of interest was in-hospital mortality comparison. We adjusted potential confounders (age, sex, diabetes, hypertension, etc.) with multivariate logistic regression analysis. Further analysis was done after balancing the population co-morbidity using a Greedy propensity match for accuracy.

Results

A total of 174,495 subjects were included in this study with a diagnosis of IE. Among these individuals, 33,285 patients had a concurrent diagnosis of thrombocytopenia. The mean ages were 53±19.5 years for the thrombocytopenia group and 55±19.8 years for others. Females were equally represented in both cohorts. There were 4,945 (14.86%) vs 2,835 (2.01%) mortalities reported in with and without thrombocytopenia group respectively. After propensity matching, there was a pronounced increase in mortality [Odds ratio (OR): 1.93 (1.72 – 2.15), p-value: &lt;0.001] in the group with thrombocytopenia comparing to others. Complications such as Major bleeding requiring blood transfusion [OR: 1.45 (1.35–1.57)], acute myocardial infarction [OR: 1.56 (1.35–1.70)], complete heart block [OR: 1.44 (1.16–1.53)], cardiac arrest [OR: 1.44 (1.25–1.72)], acute respiratory failure [OR: 1.51 (1.39–1.73)] and pressor support requirement [(OR: 1.73 (1.57–2.01)] were notably higher in the cohort of thrombocytopenia with statistically significant p-value (&lt;0.001). The difference in length of stay between both cohorts after propensity match wasn't statistically significant.

Conclusion

In conclusion, IE patients with thrombocytopenia have higher incidences of in-patient mortality and poor outcomes than cohort without thrombocytopenia. Some of the adverse consequences could be temporally explained by complications related to underlying thrombocytopenia. Further investigations are needed to delineate the outcome in this group of subjects.

Funding Acknowledgement

Type of funding sources: None.

Impact of atrial fibrillation in patients with colorectal cancer: a national inpatient sample database analysis

Background

Atrial fibrillation (AF) is the most common cardiac arrhythmia affecting approximately 1–2% overall population (1). Its causal relationship with colorectal cancer (CRC) is much for debate. According to one hypothesis, the presence of autoantibodies directed against ionic channels or acetylcholine receptors can predispose to the development of atrial fibrillation (2–3). Thus, AF may be regarded as an inflammatory complication in patients with colon cancer. Our study objective was to determine if AF impacts the outcome of patients with CRC.

Method

We analyzed the National Inpatient Sample (NIS) database from Oct-2015 to Dec 2018 using Stata 16.0. The NIS databases are released under the Healthcare Cost and Utilization Project, which includes inpatient admissions from the United States' participating hospitals. Total population with CRC were identified using their respective ICD-10 diagnostic codes then divided based on AF. To determine atrial fibrillation association with mortality and complications, we used multivariate logistic regression analysis using weights to generate nationally representative results. Later, a propensity-matched population analysis was done for the accuracy of the results.

Result

We found 245,305 patients admitted with CRC between Oct 2015 to Dec-2018 in the USA, out of which 28,170 (11.5%) were having AF. The mean age for the patients with AF was 77±10 compare to 65±14 years in those without AF. Patients with AF were associated with higher comorbidities and had a high population percentage with Carlson category three or above. There were 1,456 (5.2%) mortalities in the AF group compared to 5,689 (2.6%) in the other. The higher odds of mortality in patients with AF was present in multivariate logistic regression analysis in both non-propensity matched [1.71 (1.45–2.02), P-value: &lt;0.000] and propensity-matched [1.44 (1.18–1.75), P-value: &lt;0.001] cohorts. Patients with AF were hospitalized longer (9.20±7.8 vs. 6.85±7.0 days), leading to a high admission costs (US$ 25,875±22,875 vs. 20,087±19,314). Odds of complications such as need for blood transfusions [1.61 (1.05–1.29), P-value: 0.005], hemorrhage requiring blood transfusion [1.17 (1.05–1.29), P-value: 0.003], lower-GI bleed [1.31 (1.21–1.43), P-value: &lt;0.001], sepsis [1.45 (1.30–1.62), P-value: &lt;0.001], respiratory failure [1.39 (1.15–1.67), P-value: 0.001] etc. were also higher in group of patients with CRC and AF.

Conclusion

In our retrospective, propensity-matched national inpatient sample analyses of patients admitted with colorectal cancer, atrial fibrillation is associated with higher morbidity and mortality. AF was associated with a high burden of complications with prolonged hospital stay leading to increased health care expenditures.

Funding Acknowledgement

Type of funding sources: None.

Gender based outcome of IABP implantation in patients with acute coronary syndrome and cardiogenic shock: a national inpatient sample database analysis

Background

Intra-Aortic Balloon counter-pulsation is frequently used as a circulatory support device in patients requiring hemodynamic support - in cardiogenic shock and in patients at risk of hemodynamic decompensation during a high-risk coronary intervention. Impact of IABP in this patient population has been variable. Certain studies have shown a beneficial effect of IABP on selected populations having acute coronary syndrome with cardiogenic shock (1–3). Our objective was to compare the outcomes based on gender in the ACS population with cardiogenic shock and IABP placement.

Methods

We analyzed the National Inpatient Sample database from Oct-2015 to Dec-2017 released under Healthcare Cost utilization Project in the USA using Stata 16.0. The population was identified using respective ICD-10 codes. We excluded the population with sudden cardiac arrest, pulmonary embolism, and patients with anatomical post-MI complications. Multivariate logistic regression analysis was done to determine the difference in outcomes based on gender using clinically relevant variables. Later, propensity-matched cohort analysis was performed based on the regression variables.

Results

Of 36, 990 patients who met our inclusion criteria 25,670 (69%) were male and 11,320 (31%) were female. The average age for male and female populations was 66±11 and 69±12 years. Femnales were more likely to have higher Charlson co-morbidity index three or above. We found higher mortality in the female population [3,146 (27.79%)] compared to male [5,884 (22.92%)] in univariate analyses. Propensity-matched multivariate regression analysis showed no difference [OR: 1.06 (0.91–1.22) with P-value: 0.482] in mortality after adjusting for clinically relevant variables. Subgroup analysis in STEMI and NSTEMI populations did not show a difference. The average hospital stay was similar in both cohorts, with the male having a higher cost per stay. We found no difference in most of the complications included in our study except for higher coronary artery dissection [OR: 2.98 (1.73–5.13), P-value: &lt;0.001] and lower rates of AKI [OR: 0.72 (0.63–0.83), P-value: &lt;0.001], AKI requiring hemodialysis [OR: 0.74 (0.56–0.97), P-value:0.031] and ventricular tachycardia [OR: 0.73 (0.64–0.84), P-value: &lt;0.001] in the female population.

Conclusion

The inpatient population of ACS with Cardiogenic shock and IABP insertion showed no significant difference in mortality between males and females which was valid for subgroup analysis of NSTEMI and STEMI groups. Complications such as coronary artery dissection were higher, whereas AKI, AKI requiring hemodialysis, and ventricular tachycardias, were lower in females than males.

Funding Acknowledgement

Type of funding sources: None.

Interactions between poloxamer, PEOx-PPOy-PEOx, and non-ionic surfactant, sucrose monolaurate: A study on potential allergenic effect using model phospholipid membrane

Sugar-based surfactants are involved in skin related allergy cases in the past decade. Skin irritation starts with the interaction of the surfactant with the skin lipids leading to lipid emulsification and eventual barrier damage. Polymers or co-surfactants can be used to mitigate the allergenic effect but the mechanism of formulation mildness on skin remains unclear. We have used the quartz crystal microbalance (QCM) together with dissipative particle dynamics (DPD) simulation, small angle x-ray scattering (SAXS) as well as cell viability tests to decipher the interactions between poloxamers and sucrose monolaurate (SML), and how these interactions could prevent the disruption of a model supported phospholipid bilayer (SLB). Poloxamer addition to the SML solution can delay or totally prevent the disruption of the SLB depending on poloxamer type and concentration. Poloxamer P407 (Pluronic® F127) delays the onset of disruption while poloxamer P188 (Pluronic® F68) does not preserve the bilayer integrity even at high concentration of up to 15% w/w. Preservation of the SLB is likely due to the differences in the aggregates formation between SML-F127 and SML-F68 mixtures with corresponding retarded motion of SML micelles through the SML-F127 polymer matrix that improved cell viability.

Molecular dynamics simulation of octacosane for phase diagrams and properties via the united-atom scheme

We used the united-atom scheme to build three types of crystalline structures for octacosane (C₂₈H₅₈) and carried out molecular dynamics simulations to investigate their phase properties. By gradually heating the three polymorphs, we managed to reproduce the sequence of experimentally reported crystalline phases and rotator phases. By studying the system density, molecule morphology, chain tilt angle and cell anisotropy, we hypothesized three mechanisms behind the observed system deformations and phase transformations during the annealing process. Furthermore, our model successfully predicted the melting temperature and heat of fusion. We also reproduced the characteristics of the rotator phases and the liquid phase, validating the transferability of the united-atom scheme among the different condensed phases of octacosane. Our methodology represents an effective and efficient means of numerical study for octacosane and may be used for other members of the n-alkane family.

Linking inherent O-Linked Protein Glycosylation of YghJ to Increased Antigen Potential

Enterotoxigenic Escherichia coli (ETEC) is a WHO priority pathogen and vaccine target which causes infections in low-income and middle-income countries, travelers visiting endemic regions. The global urgent demand for an effective preventive intervention has become more pressing as ETEC strains have become increasingly multiple antibiotic resistant. However, the vaccine development pipeline has been slow to address this urgent need. To date, vaccine development has focused mainly on canonical antigens such as colonization factors and expressed toxins but due to genomic plasticity of this enteric pathogen, it has proven difficult to develop effective vaccines. In this study, we investigated the highly conserved non-canonical vaccine candidate YghJ/SsLE. Using the mass spectrometry-based method BEMAP, we demonstrate that YghJ is hyperglycosylated in ETEC and identify 54 O-linked Set/Thr residues within the 1519 amino acid primary sequence. The glycosylation sites are evenly distributed throughout the sequence and do not appear to affect the folding of the overall protein structure. Although the glycosylation sites only constitute a minor subpopulation of the available epitopes, we observed a notable difference in the immunogenicity of the glycosylated YghJ and the non-glycosylated protein variant. We can demonstrate by ELISA that serum from patients enrolled in an ETEC H10407 controlled infection study are significantly more reactive with glycosylated YghJ compared to the non-glycosylated variant. This study provides an important link between O-linked glycosylation and the relative immunogenicity of bacterial proteins and further highlights the importance of this observation in considering ETEC proteins for inclusion in future broad coverage subunit vaccine candidates.