Pathways of exposure to Vibrio Cholerae in an urban informal settlement in Nairobi, Kenya.

Cholera is a diarrhoeal disease caused by Vibrio cholerae (V. cholerae) bacterium, with strains belonging to serogroups 01 and 0139 causing a huge proportion of the disease. V. cholerae can contaminate drinking water sources and food through poor sanitation and hygiene. This study aimed to identify environmental routes of exposure to V. cholerae within Mukuru informal settlement in Nairobi. We collected nine types of environmental samples (drinking water, flood water, open drains, surface water, shaved ice, raw produce, street food, soil, and public latrine swabs) over 12 months. All samples were analysed for V. cholerae by culture and qPCR, then qPCR-positive samples were quantified using a V. cholerae DNA standard. Data about the frequency of contact with the environment was collected using behavioural surveys. Of the 803 samples collected, 28.5% were positive for V. cholerae by qPCR. However, none were positive for V. cholerae by culture. V. cholerae genes were detected in majority of the environmental water samples (79.3%), including open drains, flood water, and surface water, but were only detected in small proportions of other sample types. Vibrio-positive environmental water samples had higher mean V. cholerae concentrations [2490-3469 genome copies (gc) per millilitre (mL)] compared to drinking water samples (25.6 gc/mL). Combined with the behavioural data, exposure assessment showed that contact with surface water had the highest contribution to the total V. cholerae exposure among children while ingestion of municipal drinking water and street food and contact with surface water made substantial contributions to the total V. cholerae exposure for adults. Detection of V. cholerae in street food and drinking water indicates possible risk of exposure to toxigenic V. cholerae in this community. Exposure to V. cholerae through multiple pathways highlights the need to improve water and sanitation infrastructure, strengthen food hygiene practices, and roll out cholera vaccination.

Targeting Metabolic-Redox Nexus to Regulate Drug Resistance: From Mechanism to Tumor Therapy.

Drug resistance is currently one of the biggest challenges in cancer treatment. With the deepening understanding of drug resistance, various mechanisms have been revealed, including metabolic reprogramming and alterations of redox balance. Notably, metabolic reprogramming mediates the survival of tumor cells in harsh environments, thereby promoting the development of drug resistance. In addition, the changes during metabolic pattern shift trigger reactive oxygen species (ROS) production, which in turn regulates cellular metabolism, DNA repair, cell death, and drug metabolism in direct or indirect ways to influence the sensitivity of tumors to therapies. Therefore, the intersection of metabolism and ROS profoundly affects tumor drug resistance, and clarifying the entangled mechanisms may be beneficial for developing drugs and treatment methods to thwart drug resistance. In this review, we will summarize the regulatory mechanism of redox and metabolism on tumor drug resistance and highlight recent therapeutic strategies targeting metabolic-redox circuits, including dietary interventions, novel chemosynthetic drugs, drug combination regimens, and novel drug delivery systems.

Characterization of three non-canonical N-glycosylation motifs indicates Nglyco-A reduces DNA N6-methyladenine and Nglyco-D alters G/F actin ratio in Phytophthora sojae.

Asparagine (Asn, N)-linked glycosylation is an abundant post-translational modification in which Asn, typically in Nglyco-X-S/T; X ≠ P motifs, are modified with N-glycans. It has essential regulatory roles in multicellular organisms. In this study, we systematically investigate the function of three N-glycosylation motifs (Nglyco-A, Nglyco-D and Nglyco-S) previously identified in Phytophthora sojae, through site-directed mutagenesis and functional assays. In P. sojae expressing glycosylation-dead variants pre-PsDMAP1N70A (Nglyco-A motif) or PsADFN64A (Nglyco-D motif), zoospore release or cyst germination is impaired. In particular, the pre-PsDMAP1N70A mutant reduces DNA methylation levels, and the PsADFN64A mutant disrupts the actin forms, which could explain the decrease in pathogenicity after N-glycosylation is destroyed. Similarly, P. sojae expressing PsNRXN132A (Nglyco-S motif) shows increased sensitivity to H2O2 and heat. Through autophagy or 26S proteasome pathway inhibition assays, we found that unglycosylated pre-PsDMAP1N70A and PsADFN64A are degraded via the 26S proteasome pathway, while the autophagy pathway is responsible for PsNRXN132A clearance. These findings demonstrate that glycosylation of these motifs regulates the stability and function of glycoproteins necessary for P. sojae growth, reproduction and pathogenicity, which expands the scope of known N-glycosylation regulatory functions in oomycetes.

Semi-automated protocol to quantify and characterize fluorescent three-dimensional vascular images.

The microvasculature facilitates gas exchange, provides nutrients to cells, and regulates blood flow in response to stimuli. Vascular abnormalities are an indicator of pathology for various conditions, such as compromised vessel integrity in small vessel disease and angiogenesis in tumors. Traditional immunohistochemistry enables the visualization of tissue cross-sections containing exogenously labeled vasculature. Although this approach can be utilized to quantify vascular changes within small fields of view, it is not a practical way to study the vasculature on the scale of whole organs. Three-dimensional (3D) imaging presents a more appropriate method to visualize the vascular architecture in tissue. Here we describe the complete protocol that we use to characterize the vasculature of different organs in mice encompassing the methods to fluorescently label vessels, optically clear tissue, collect 3D vascular images, and quantify these vascular images with a semi-automated approach. To validate the automated segmentation of vascular images, one user manually segmented one hundred random regions of interest across different vascular images. The automated segmentation results had an average sensitivity of 83±11% and an average specificity of 91±6% when compared to manual segmentation. Applying this procedure of image analysis presents a method to reliably quantify and characterize vascular networks in a timely fashion. This procedure is also applicable to other methods of tissue clearing and vascular labels that generate 3D images of microvasculature.

Targeting CD8+ T cells with natural products for tumor therapy: Revealing insights into the mechanisms.

BACKGROUND: Despite significant advances in cancer immunotherapy over the past decades, such as T cell-engaging chimeric antigen receptor (CAR)-T cell therapy and immune checkpoint blockade (ICB), therapeutic failure resulting from various factors remains prevalent. Therefore, developing combinational immunotherapeutic strategies is of great significance for improving the clinical outcome of cancer immunotherapy. Natural products are substances that naturally exist in various living organisms with multiple pharmacological or biological activities, and some of them have been found to have anti-tumor potential. Notably, emerging evidences have suggested that several natural compounds may boost the anti-tumor effects through activating immune response of hosts, in which CD8+ T cells play a pivotal role. METHODS: The data of this review come from PubMed, Web of Science, Google Scholar, and ClinicalTrials (https://clinicaltrials.gov/) with the keywords "CD8+ T cell", "anti-tumor", "immunity", "signal 1", "signal 2", "signal 3", "natural products", "T cell receptor (TCR)", "co-stimulation", "co-inhibition", "immune checkpoint", "inflammatory cytokine", "hesperidin", "ginsenoside", "quercetin", "curcumin", "apigenin", "dendrobium officinale polysaccharides (DOPS)", "luteolin", "shikonin", "licochalcone A", "erianin", "resveratrol", "procyanidin", "berberine", "usnic acid", "naringenin", "6-gingerol", "ganoderma lucidum polysaccharide (GL-PS)", "neem leaf glycoprotein (NLGP)", "paclitaxel", "source", "pharmacological activities", and "toxicity". These literatures were published between 1993 and 2023. RESULTS: Natural products have considerable advantages as anti-tumor drugs based on the various species, wide distribution, low price, and few side effects. This review summarized the effects and mechanisms of some natural products that exhibit anti-tumor effects via targeting CD8+ T cells, mainly focused on the three signals that activate CD8+ T cells: TCR, co-stimulation, and inflammatory cytokines. CONCLUSION: Clarifying the role and underlying mechanism of natural products in cancer immunotherapy may provide more options for combinational treatment strategies and benefit cancer therapy, to shed light on identifying potential natural compounds for improving the clinical outcome in cancer immunotherapy.

Correlation of SARS-CoV-2 in Wastewater and Individual Testing Results in a Jail, Atlanta, Georgia, USA.

Institution-level wastewater-based surveillance was implemented during the COVID-19 pandemic, including in carceral facilities. We examined the relationship between COVID-19 diagnostic test results of residents in a jail in Atlanta, Georgia, USA (average population ≈2,700), and quantitative reverse transcription PCR signal for SARS-CoV-2 in weekly wastewater samples collected during October 2021‒May 2022. The jail offered residents rapid antigen testing at entry and periodic mass screenings by reverse transcription PCR of self-collected nasal swab specimens. We aggregated individual test data, calculated the Spearman correlation coefficient, and performed logistic regression to examine the relationship between strength of SARS-CoV-2 PCR signal (cycle threshold value) in wastewater and percentage of jail population that tested positive for COVID-19. Of 13,745 nasal specimens collected, 3.9% were COVID-positive (range 0%-29.5% per week). We observed a strong inverse correlation between diagnostic test positivity and cycle threshold value (r = -0.67; p<0.01). Wastewater-based surveillance represents an effective strategy for jailwide surveillance of COVID-19.

Intravital imaging of splenic classical monocytes modifying the hepatic CX3CR1+ cells motility to exacerbate liver fibrosis via spleen-liver axis.

CX3CR1+ cells play a crucial role in liver fibrosis progression. However, changes in the migratory behavior and spatial distribution of spleen-derived and hepatic CX3CR1+ cells in the fibrotic liver as well as their influence on the liver fibrosis remain unclear. METHODS: The CX3CR1GFP/+ transgenic mice and CX3CR1-KikGR transgenic mice were used to establish the CCl4-induced liver fibrosis model. Splenectomy, adoptive transfusion of splenocytes, in vivo photoconversion of splenic CX3CR1+ cells and intravital imaging were performed to study the spatial distribution, migration and movement behavior, and regulatory function of CX3CR1+ cells in liver fibrosis. RESULTS: Intravital imaging revealed that the CX3CR1GFP cells accumulated into the fibrotic liver and tended to accumulate towards the central vein (CV) in the hepatic lobules. Two subtypes of hepatic CX3CR1+ cells existed in the fibrotic liver. The first subtype was the interacting CX3CR1GFP cells, most of which were observed to distribute in the liver parenchyma and had a higher process velocity; the second subtype was mobile CX3CR1GFP cells, most of which were present in the hepatic vessels with a faster moving speed. Splenectomy ameliorated liver fibrosis and decreased the number of CX3CR1+ cells in the fibrotic liver. Moreover, splenectomy rearranged CX3CR1GFP cells to the boundary of the hepatic lobule, reduced the process velocity of interacting CX3CR1GFP cells and decreased the number and mobility of mobile CX3CR1GFP cells in the fibrotic liver. Transfusion of spleen-derived classical monocytes increased the process velocity and mobility of hepatic endogenous CX3CR1GFP cells and facilitated liver fibrosis progression via the production of proinflammatory and profibrotic cytokines. The photoconverted splenic CX3CR1+ KikRed+ cells were observed to leave the spleen, accumulate into the fibrotic liver and contact with hepatic CX3CR1+ KikGreen+ cells during hepatic fibrosis. CONCLUSION: The splenic CX3CR1+ monocytes with classical phenotype migrated from the spleen to the fibrotic liver, modifying the migratory behavior of hepatic endogenous CX3CR1GFP cells and exacerbating liver fibrosis via the secretion of cytokines. This study reveals that splenic CX3CR1+ classical monocytes are a key driver of liver fibrosis via the spleen-liver axis and may be potential candidate targets for the treatment of chronic liver fibrosis.

Acute toxicology on Danio rerio embryo and adult from Chinese traditional medicine preparation Danggui Shaoyao san.

ETHNOPHARMACOLOGICAL RELEVANCE: Although the Traditional Chinese Medicine (TCM) prescription of Danggui Shaoyao San (DSS) presents substantial clinical efficacy and promising clinical prospects, the safety of DSS and its extracts have been inadequately investigated. The larva-adult duality of the zebrafish model offers a more efficient approach for evaluating the safety of herbal preparations in the fields of toxicology and pharmacology. AIM OF THE STUDY: To investigate the acute toxicity of the extract derived from Danggui Shaoyao San, a traditional Chinese medicine preparation, on both Danio rerio embryos and adult organisms. MATERIALS AND METHODS: The components of DSS were identified using liquid chromatography-tandem mass spectrometry (LC-MS/MS). The hatching rate of Danio rerio juveniles with different concentrations of DSS was calculated and the morphological changes of juveniles after administration were observed through a microscope. The behavioral trajectory of the adult fish was recorded by the observation tower of the automated Danio rerio analysis system, and DSS's effects on the behavior was analyzed. The pathological changes of Danio rerio gills, livers, kidneys, intestines and spermaries were examined using HE staining. RESULTS: Compared with the control group, 25, 50 and 100 mg/L of DSS did not elicit any significant impacts on the hatching rate and morphology. Both 200 mg/L and the propylene glycol 2% reduced the hatching rate and caused the morphological teratogenic changes of the juvenile fish. The dosage of DSS below 100 mg/L had no discernible effect on the behavior of the adult fish, whereas the application of propylene glycol 2% was found to stimulate the adult fish, resulting in a notable increase in high-speed movement distance. 100 mg/L DSS group was not observed to cause any noticeable damage to the gills, livers, intestines and spermaries of Danio rerio, only mild nephrotoxicity was detected. The propylene glycol 2% group was found to result in pathological changes such as hyperplasia of epithelial cells on secondary lamellae, liver cell outline loss or atypia, tubal disorganization, goblet cell hypertrophy and irregularly arranged spermatozoa. CONCLUSION: A viable approach for conducting toxicological studies on TCM preparations was developed and tested in this research. The findings showed that Danggui Shaoyao San has minimal acute toxicity to embryos and adult organisms at concentrations up to 100 mg/L. These results indicate that Danggui Shaoyao San is a safe TCM preparation.

Intravital imaging of the functions of immune cells in the tumor microenvironment during immunotherapy.

Cancer immunotherapy has developed rapidly in recent years and stands as one of the most promising techniques for combating cancer. To develop and optimize cancer immunotherapy, it is crucial to comprehend the interactions between immune cells and tumor cells in the tumor microenvironment (TME). The TME is complex, with the distribution and function of immune cells undergoing dynamic changes. There are several research techniques to study the TME, and intravital imaging emerges as a powerful tool for capturing the spatiotemporal dynamics, especially the movement behavior and the immune function of various immune cells in real physiological state. Intravital imaging has several advantages, such as high spatio-temporal resolution, multicolor, dynamic and 4D detection, making it an invaluable tool for visualizing the dynamic processes in the TME. This review summarizes the workflow for intravital imaging technology, multi-color labeling methods, optical imaging windows, methods of imaging data analysis and the latest research in visualizing the spatio-temporal dynamics and function of immune cells in the TME. It is essential to investigate the role played by immune cells in the tumor immune response through intravital imaging. The review deepens our understanding of the unique contribution of intravital imaging to improve the efficiency of cancer immunotherapy.

Danggui Shaoyao San ameliorates the lipid metabolism via the PPAR signaling pathway in a Danio rerio (zebrafish) model of hyperlipidemia.

The escalating prevalence of hyperlipidemia has a profound impact on individuals' daily physiological well-being. The traditional Chinese medicine (TCM) prescription Danggui Shaoyao San (DSS) has demonstrated significant clinical efficacy and promising prospects for clinical application. Leveraging network pharmacology and bioinformatics, we hypothesize that DSS can ameliorate lipid metabolic disorders in hyperlipidemia by modulating the PPAR signaling pathway. In this study, we employed a zebrafish model to investigate the impact of DSS on lipid metabolism in hyperlipidemia. Body weight alterations were monitored by pre- and postmodeling weight measurements. Behavioral assessments and quantification of liver biochemical markers were conducted using relevant assay kits. Pathways associated with lipid metabolism were identified through network pharmacology and GEO analysis, while PCR was utilized to assess genes linked to lipid metabolism. Western blotting was employed to analyze protein expression levels, and liver tissue underwent Oil Red O and immunofluorescence staining to evaluate liver lipid deposition. Our findings demonstrate that DSS effectively impedes weight gain and reduces liver lipid accumulation in zebrafish models with elevated lipid levels. The therapeutic effects of DSS on lipid metabolism are mediated through its modulation of the PPAR signaling pathway, resulting in a significant reduction in lipid accumulation within the body and alleviation of certain hyperlipidemia-associated symptoms.

Causal associations between sleep traits and brain structure: a bidirectional Mendelian randomization study.

BACKGROUND: Emerging evidence suggests bidirectional causal relationships between sleep disturbance and psychiatric disorders, but the underlying mechanisms remain unclear. Understanding the bidirectional causality between sleep traits and brain imaging-derived phenotypes (IDPs) will help elucidate the mechanisms. Although previous studies have identified a range of structural differences in the brains of individuals with sleep disorders, it is still uncertain whether grey matter (GM) volume alterations precede or rather follow from the development of sleep disorders. RESULTS: After Bonferroni correction, the forward MR analysis showed that insomnia complaint remained positively associated with the surface area (SA) of medial orbitofrontal cortex (ß, 0.26; 95% CI, 0.15-0.37; P = 5.27 × 10-6). In the inverse MR analysis, higher global cortical SA predisposed individuals less prone to suffering insomnia complaint (OR, 0.89; 95%CI, 0.85-0.94; P = 1.51 × 10-5) and short sleep (≤ 6 h; OR, 0.98; 95%CI, 0.97-0.99; P = 1.51 × 10-5), while higher SA in posterior cingulate cortex resulted in a vulnerability to shorter sleep durations (ß, - 0.09; 95%CI, - 0.13 to - 0.05; P = 1.21 × 10-5). CONCLUSIONS: Sleep habits not only result from but also contribute to alterations in brain structure, which may shed light on the possible mechanisms linking sleep behaviours with neuropsychiatric disorders, and offer new strategies for prevention and intervention in psychiatric disorders and sleep disturbance.

Estimating seroconversion rates accounting for repeated infections by approximate Bayesian computation.

This study presents a novel approach for inferring the incidence of infections by employing a quantitative model of the serum antibody response. Current methodologies often overlook the cumulative effect of an individual's infection history, making it challenging to obtain a marginal distribution for antibody concentrations. Our proposed approach leverages approximate Bayesian computation to simulate cross-sectional antibody responses and compare these to observed data, factoring in the impact of repeated infections. We then assess the empirical distribution functions of the simulated and observed antibody data utilizing Kolmogorov deviance, thereby incorporating a goodness-of-fit check. This new method not only matches the computational efficiency of preceding likelihood-based analyses but also facilitates the joint estimation of antibody noise parameters. The results affirm that the predictions generated by our within-host model closely align with the observed distributions from cross-sectional samples of a well-characterized population. Our findings mirror those of likelihood-based methodologies in scenarios of low infection pressure, such as the transmission of pertussis in Europe. However, our simulations reveal that in settings of higher infection pressure, likelihood-based approaches tend to underestimate the force of infection. Thus, our novel methodology presents significant advancements in estimating infection incidence, thereby enhancing our understanding of disease dynamics in the field of epidemiology.

Ring1a protects against colitis through regulating mucosal immune system and colonic microbial ecology.

Inflammatory bowel disease (IBD) represents a prominent chronic immune-mediated inflammatory disorder, yet its etiology remains poorly comprehended, encompassing intricate interactions between genetics, immunity, and the gut microbiome. This study uncovers a novel colitis-associated risk gene, namely Ring1a, which regulates the mucosal immune response and intestinal microbiota. Ring1a deficiency exacerbates colitis by impairing the immune system. Concomitantly, Ring1a deficiency led to a Prevotella genus-dominated pathogenic microenvironment, which can be horizontally transmitted to co-housed wild type (WT) mice, consequently intensifying dextran sodium sulfate (DSS)-induced colitis. Furthermore, we identified a potential mechanism linking the altered microbiota in Ring1aKO mice to decreased levels of IgA, and we demonstrated that metronidazole administration could ameliorate colitis progression in Ring1aKO mice, likely by reducing the abundance of the Prevotella genus. We also elucidated the immune landscape of DSS colitis and revealed the disruption of intestinal immune homeostasis associated with Ring1a deficiency. Collectively, these findings highlight Ring1a as a prospective candidate risk gene for colitis and suggest metronidazole as a potential therapeutic option for clinically managing Prevotella genus-dominated colitis.

We found that PcG protein Ring1a could be a new risk gene for colitis. Ring1a deficiency causes aggravated colitis by regulating the mucosal immune system and colonic microbial ecology.

Functional connectomic profile correlates with effective anterior thalamic stimulation for refractory epilepsy.

BACKGROUND: Deep brain stimulation of the anterior nucleus of the thalamus (ANT-DBS) is an effective treatment for refractory epilepsy; however, seizure outcome varies among individuals. Identifying a reliable noninvasive biomarker to predict good responders would be helpful. OBJECTIVES: To test whether the functional connectivity between the ANT-DBS sites and the seizure foci correlates with effective seizure control in refractory epilepsy. METHODS: We performed a proof-of-concept pilot study of patients with focal refractory epilepsy receiving ANT-DBS. Using normative human connectome data derived from 1000 healthy participants, we investigated whether intrinsic functional connectivity between the seizure foci and the DBS site was associated with seizure outcome. We repeated this analysis controlling for the extent of seizure foci, distance between the seizure foci and DBS site, and using functional connectivity of the ANT instead of the DBS site to test the contribution of variance in DBS sites. RESULTS: Eighteen patients with two or more seizure foci were included. Greater functional connectivity between the seizure foci and the DBS site correlated with more favorable outcome. The degree of functional connectivity accounted for significant variance in clinical outcomes (DBS site: |r| = 0.773, p < 0.001 vs ANT-atlas: |r| = 0.715, p = 0.001), which remained significant when controlling for the extent of the seizure foci (|r| = 0.773, p < 0.001) and the distance between the seizure foci and DBS site (|r| = 0.777, p < 0.001). Significant correlations were independent of variance in the DBS sites (|r| = 0.148, p = 0.57). CONCLUSION: These findings suggest that functional connectomic profile is a potential reliable non-invasive biomarker to predict ANT-DBS outcomes. Accordingly, the identification of ANT responders could decrease the surgical risk for patients who may not benefit and optimize the cost-effective allocation of health care resources.

Human anterior thalamic stimulation evoked cortical potentials align with intrinsic functional connectivity.

Characterizing human thalamocortical network is fundamental for understanding a vast array of human behaviors since the thalamus plays a central role in cortico-subcortical communication. Over the past few decades, advances in functional magnetic resonance imaging have allowed for spatial mapping of intrinsic resting-state functional connectivity (RSFC) between both cortical regions and in cortico-subcortical networks. Despite these advances, identifying the electrophysiological basis of human thalamocortical network architecture remains challenging. By leveraging stereoelectroencephalography electrodes temporarily implanted into distributed cortical regions and the anterior nucleus of the thalamus (ANT) of 10 patients with refractory focal epilepsy, we tested whether ANT stimulation evoked cortical potentials align with RSFC from the stimulation site, derived from a normative functional connectome (n = 1000). Our study identifies spatial convergence of ANT stimulation evoked cortical potentials and normative RSFC. Other than connections to the Papez circuit, the ANT was found to be closely connected to several distinct higher-order association cortices, including the precuneus, angular gyrus, dorsal lateral prefrontal cortex, and anterior insula. Remarkably, we found that the spatial distribution and magnitude of cortical-evoked responses to single-pulse electrical stimulation of the ANT aligned with the spatial pattern and strength of normative RSFC of the stimulation site. The present study provides electrophysiological evidence that stimulation evoked electrical activity flows along intrinsic brain networks connected on a thalamocortical level.

Activation of trace LiNO3 additives by BF3 in high-concentration electrolytes towards stable lithium metal batteries.

The activation of trace LiNO3 additives in high-concentration electrolytes is achieved by BF3 due to its Lewis acidity. This advanced electrolyte can promote the decomposition of LiNO3 into Li3N, attaining enhanced cycle reversibility of lithium anodes, which broadens the application of LiNO3 additives.

When case reporting becomes untenable: Can sewer networks tell us where COVID-19 transmission occurs?

Monitoring SARS-CoV-2 in wastewater is a valuable approach to track COVID-19 transmission. Designing wastewater surveillance (WWS) with representative sampling sites and quantifiable results requires knowledge of the sewerage system and virus fate and transport. We developed a multi-level WWS system to track COVID-19 in Atlanta using an adaptive nested sampling strategy. From March 2021 to April 2022, 868 wastewater samples were collected from influent lines to wastewater treatment facilities and upstream community manholes. Variations in SARS-CoV-2 concentrations in influent line samples preceded similar variations in numbers of reported COVID-19 cases in the corresponding catchment areas. Community sites under nested sampling represented mutually-exclusive catchment areas. Community sites with high SARS-CoV-2 detection rates in wastewater covered high COVID-19 incidence areas, and adaptive sampling enabled identification and tracing of COVID-19 hotspots. This study demonstrates how a well-designed WWS provides actionable information including early warning of surges in cases and identification of disease hotspots.

Estimates of the cost to build a stand-alone environmental surveillance system for typhoid in low- and middle-income countries.

The typhoid conjugate vaccine is a safe and effective method for preventing Salmonella enterica serovar Typhi (typhoid) and the WHO's guidance supports its use in locations with ongoing transmission. However, many countries lack a robust clinical surveillance system, making it challenging to determine where to use the vaccine. Environmental surveillance is one alternative approach to identify ongoing transmission, but the cost to implement such a strategy is previously unknown. This paper estimated the cost of setting up and operating an environmental surveillance program for thirteen protocols that are in development, including thirteen cost components and twenty-seven pieces of equipment. Unit costs were obtained from research labs involved in protocol development and equipment information was obtained from manufacturers and the expert opinion of individuals in participating labs. We used Monte Carlo simulations to estimate the costs and the input parameters were modeled as distributions to incorporate the uncertainty. Total costs per sample including setup, overhead, and operational costs, range from $357-794 at a scale of 25 sites to $116-532 at 125 sites. Operational costs (ongoing expenditures) range from $218-584 per sample at a scale of 25 sites to $74-421 at 125 sites. Eleven of the thirteen protocols have operational costs below $200, at this higher scale. Protocols with higher up-front equipment costs benefit more from scale efficiencies and sensitivity analyses show that laboratory labor, processes, and consumables are the primary drivers of uncertainty. At scale, environmental surveillance for typhoid may be affordable (depending on the protocol, scale, and geographic context), though cost will need to be considered alongside future evaluations of test sensitivity. Opportunities to leverage existing infrastructure and multi-disease platforms may be necessary to further reduce costs.

Preparation of 2D Materials and Their Application in Oil-Water Separation.

The problems of environmental pollution are increasingly severe. Among them, industrial wastewater is one of the primary sources of pollution, so it is essential to deal with wastewater, especially oil and water mixtures. At present, biomimetic materials with special wettability have been proven to be effective in oil-water separation. Compared with three-dimensional (3D) materials, two-dimensional (2D) materials show unique advantages in the preparation of special wettable materials due to their high specific surface area, high porosity, controlled structure, and rich functional group rich on the surface. In this review, we first introduce oil-water mixtures and the common oil-water separation mechanism. Then, the research progress of 2D materials in oil-water separation is presented, including but not limited to their structure, types, preparation principles, and methods. In addition, it is still impossible to prepare 2D materials with large sizes because they are powder-like, which greatly limits the application in oil-water separation. Therefore, we provide here a review of several ways to transform 2D materials into 3D materials. In the end, the challenges encountered by 2D materials in separating oil-water are also clarified to promote future applications.