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Surface water plays a vital role in the spread of infectious diseases. Information on the spatial and temporal dynamics of surface water availability is thus critical to understanding, monitoring and forecasting disease outbreaks. Before the launch of Sentinel-1 Synthetic Aperture Radar (SAR) missions, surface water availability has been captured at various spatial scales through approaches based on optical remote sensing data. A critical drawback of the latter is data loss due to cloud cover, however few studies have quantified this. This study evaluated data loss due to clouds in three Western Ghats (India) districts. These forest-agricultural mosaic landscapes, where water-related diseases are prevalent, experience the Indian monsoon. We compared surface water areas mapped by thresholding 10m Sentinel-1A SAR data with the optical 30m Landsat-derived Joint Research Centre (JRC) Global Surface Water product, currently the only globally available long-term monthly surface water data product. Backscatter thresholds were identified manually, and our Bayesian algorithm found these thresholds were very likely (>97%). While the Sentinel-1 SAR-based and JRC's optical-based approach mapped surface water extent with high overall accuracy (> 98%) when the cloud cover was low, the unmapped surface water area was substantial in the JRC product during the monsoon months. Across the districts, the average cloud cover in the July-August period was 92% or 90% for 2017 and 2018 respectively, resulting in 25% or 23% of the surface water area being unmapped. Also, the more detailed 10m resolution of Sentinel-1A SAR helped detect the many small water features missed by 30m JRC. Thus, for predicting water-related disease risks linked to small water features or monsoon rainfall, Sentinel-1A SAR is more effective. Finally, automatic backscatter thresholding for unvegetated surface water mapping can be effective if threshold values are adapted to regional-specific backscatter spatial and temporal variations. [ABSTRACT FROM AUTHOR]

Background: Kyasanur forest disease virus (KFDV) is a tick-borne flavivirus causing debilitating and potentially fatal disease in people in the Western Ghats region of India. The transmission cycle is complex, involving multiple vector and host species, but there are significant gaps in ecological knowledge. Empirical data on pathogen-vector-host interactions and incrimination have not been updated since the last century, despite significant local changes in land use and the expansion of KFD to new areas. Mathematical models predict that transovarial transmission, whereby adult female ticks pass KFDV infections to their offspring, plays an important role in the persistence of KFD, but this has not been shown in the wild. Here we set out to establish whether transovarial transmission of KFDV was occurring under natural field conditions by assessing whether host-seeking larvae were positive for KFDV. Methods: Ticks were sampled by dragging and flagging across a broad range of habitats within the agro-forest matrix at 49 sites in two districts: Shivamogga, Karnataka and Wayanad, Kerala (September 2018-March 2019), and larvae were tested for KFDV by PCR. Results: In total, larval ticks from 7 of the 49 sites sampled tested positive for KFDV, indicating that transovarial transmission is occurring. Of the 13 KFDV-positive larval samples, 3 came from around houses and gardens, 5 from crops (3 from harvested rice paddy and 2 from areca plantation), 1 from teak plantation and 4 (2 from 1 transect) from forests. Five different tick species were found to have KFDV-positive larvae: Haemaphysalis spinigera, H. bispinosa, Rhipicephalus annulatus, R. microplus and an unidentifiable species of Haemaphysalis (no close match in GenBank). Conclusions: Our empirical confirmation of transovarial transmission has important implications for understanding and predicting KFD dynamics, suggesting that ticks may act as a reservoir for KFDV. Moreover, small mammals and cattle may play crucial roles in transmission if small mammals are the main hosts for larvae infected via transovarial transmission, and cattle support large numbers of infected female adult ticks. This first report of transovarial transmission of KFDV, and within a hitherto undescribed range of vectors and habitats, will help disease managers improve KFD surveillance and mitigation strategies, ultimately leading to communities becoming more resilient to the risk of this tick-transmitted disease. [ABSTRACT FROM AUTHOR]

Introduction: Inflammatory bowel disease (IBD), including ulcerative colitis, is marked by intestinal barrier disruptions, immune system dysregulation, and an imbalance in the gut microbiota. The golden chanterelle mushroom, Cantharellus cibarius Fr., a popular edible mushroom, has shown potential therapeutic benefits. This study examines the therapeutic potential of a crude polysaccharide extract obtained from C. cibarius Fr. (CCP) on intestinal barrier integrity, inflammatory cytokine levels, and gut microbiota composition in a murine model of colitis induced by dextran sulfate sodium (DSS). Methods: To induce colitis BALB/c mice were provided to consume autoclaved water with 3% DSS for 7 days, followed by 14 days of CCP supplementation. To assess the effects of CCP, histological analysis of colon tissue was performed, gene expression, inflammatory responses, tight junction proteins expression, gut barrier integrity, and cytokines levels were measured and analyzed and 16S rRNA sequencing were evaluated. Results and Discussion: CCP treatment alleviates colitis symptoms by improving body weight, and enhancing intestinal integrity through increased mucin-2 and tight junction protein expression. Additionally, CCP administration regulates the altered immune response by mitigating the expression of pro-inflammatory cytokines and upregulating anti-inflammatory cytokines. Furthermore, CCP supplementation effectively modulates DSS-induced dysbiosis as demonstrated by 16S rRNA sequencing results. These findings suggest that crude polysaccharides from the golden chanterelle mushroom, C. cibarius Fr., hold promise for treating colitis, via strengthening the intestinal barrier, regulating inflammatory responses, and reshaping the gut dysbiosis in a DSS-induced colitis model. CCP offers a novel approach for managing colitis, as a chronic inflammatory condition. [ABSTRACT FROM AUTHOR]

Inflammatory bowel disease (IBD) is a chronic inflammatory condition of the gastrointestinal tract. Sea conch peptide hydrolysate (CPH) was produced by enzymatic digestion of fresh conch meat with trypsin enzyme. To analyze the molecular composition, functional groups, and structural morphology of the hydrolysate, we employed liquid chromatography–mass spectrometry (LC–MS), Fourier‐transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM). Results confirmed that crude protein could be effectively digested by enzymes to generate peptides. In this study, we evaluated the bioactivities of CPH on dextran sulfate solution (DSS)‐induced colitis in mice. The findings demonstrated that CPH supplementation improved body weight, food and water intake, and colon length. The therapeutic efficacy and immunoregulatory effect of CPH were further determined. Our results exhibited that CPH treatment significantly ameliorated pathological symptoms by enhancing intestinal integrity, mucin production, and goblet cell count. Moreover, the immunoregulatory effect of CPH on mRNA expression levels of different pro‐ and anti‐inflammatory cytokines was determined. Results exhibited a decrease in the expression of pro‐inflammatory cytokines and an increase in anti‐inflammatory cytokines in the colon. Additionally, the CPH administration modulates the nuclear factor kappa B (NF‐κB) pathway, preventing DNA damage and cell death. Assays for apoptosis and DNA damage revealed that CPH reduced oxidative DNA damage and apoptosis. These findings highlight the immunomodulatory and treatment amelioration effect of CPH in reducing the severity of colitis. [ABSTRACT FROM AUTHOR]

Bioconvection in hybrid nanofluids refers to the phenomenon where biological microorganisms such as algae or bacteria exhibit collective movement or pattern formation in a suspension containing nanoparticles. This phenomenon has significance in various fields, including biology, nanotechnology, and engineering. The current investigation emphasizes the bioconvective flow of a water (H2O)−ethylene glycol (C2H6O2)-based hybrid nanofluid flow by a curved stretched sheet. Copper (Cu) and silver (Ag) nanoparticles are suspended in the base fluid. The thermal field is analyzed in the presence of heat generation, dissipation, Joule heating, and the impact of thermal radiation. Binary reactions associated with Arrhenius energy are accounted in the modeling of mass concentration. The phenomenon of bioconvection is considered to regulate the random movement of tiny solid particles within the flow. Boundary layer constraints are implemented to eliminate ineffective terms from modeling. The transformation procedure is adopted to obtain the flow governing system of ODEs. The built-in code of Mathematica (NDSolve) is implemented to obtain the graphical and numerical results. The results show that the velocity field decreases with increasing porosity variable and Hartmann number. An opposite impression of the Eckert number and Schmidt variable on the thermal field is noticed. Bioconvection Peclet and Lewis numbers have a direct relationship with motile density. [ABSTRACT FROM AUTHOR]