Membrane Lipids Augment Cell Envelope Stress Signaling via the MadRS System to Defend Against Antimicrobial Peptides and Antibiotics in Enterococcus faecalis.

Enterococci have evolved resistance mechanisms to protect their cell envelopes against bacteriocins and host cationic antimicrobial peptides (CAMPs) produced in the gastrointestinal environment. Activation of the membrane stress response has also been tied to resistance to the lipopeptide antibiotic daptomycin. However, the actual effectors mediating resistance have not been elucidated. Here, we show that the MadRS (formerly YxdJK) membrane antimicrobial peptide defense system controls a network of genes, including a previously uncharacterized three gene operon (madEFG) that protects the E. faecalis cell envelope from antimicrobial peptides. Constitutive activation of the system confers protection against CAMPs and daptomycin in the absence of a functional LiaFSR system and leads to persistence of cardiac microlesions in vivo. Moreover, changes in the lipid cell membrane environment alter CAMP susceptibility and expression of the MadRS system. Thus, we provide a framework supporting a multilayered envelope defense mechanism for resistance and survival coupled to virulence.

Optimization of the antifungal properties of the bacterial peptide EntV by variant analysis.

Fungal resistance to commonly used medicines is a growing public health threat, and there is a dire need to develop new classes of antifungals. We previously described a peptide produced by Enterococcus faecalis, EntV, that restricts Candida albicans to a benign form rather than having direct fungicidal activity. Moreover, we showed that one 12-amino acid (aa) alpha helix of this peptide retained full activity, with partial activity down to the 10aa alpha helix. Using these peptides as a starting point, the current investigation sought to identify the critical features necessary for antifungal activity and to screen for new variants with enhanced activity using both biofilm and C. elegans infection assays. First, the short peptides were screened for residues with critical activity by generating alanine substitutions. Based on this information, we used synthetic molecular evolution (SME) to rationally vary the specific residues of the 10aa variant in combination to generate a library that was screened to identify variants with more potent antifungal activity than the parent template. Five gain-of-function peptides were identified. Additionally, chemical modifications to the peptides to increase stability, including substitutions of D-amino acids and hydrocarbon stapling, were investigated. The most promising peptides were additionally tested in mouse models of oropharyngeal and systemic candidiasis where their efficacy in preventing infection was demonstrated. The expectation is that these discoveries will contribute to the development of new therapeutics in the fight against antimicrobial resistant fungi. IMPORTANCE: Since the early 1980s, the incidence of disseminated life-threatening fungal infections has been on the rise. Worldwide, Candida and Cryptococcus species are among the most common agents causing these infections. Simultaneously, with this rise of clinical incidence, there has also been an increased prevalence of antifungal resistance, making treatment of these infections very difficult. For example, there are now strains of Candida auris that are resistant to all three classes of currently used antifungal drugs. In this study, we report on a strategy that allows for the development of novel antifungal agents by using synthetic molecular evolution. These discoveries demonstrate that the enhancement of antifungal activity from naturally occurring peptides is possible and can result in clinically relevant agents that have efficacy in multiple in vivo models as well as the potential for broad-spectrum activity.

Membrane Lipids Augment Cell Envelope Stress Signaling and Resistance to Antibiotics and Antimicrobial Peptides in Enterococcus faecalis.

Enterococci have evolved resistance mechanisms to protect their cell envelopes against bacteriocins and host cationic antimicrobial peptides (CAMPs) produced in the gastrointestinal environment. Activation of the membrane stress response has also been tied to resistance to the lipopeptide antibiotic daptomycin. However, the actual effectors mediating resistance have not been elucidated. Here, we show that the MadRS (formerly YxdJK) membrane antimicrobial peptide defense system controls a network of genes, including a previously uncharacterized three gene operon (madEFG) that protects the E. faecalis cell envelope from antimicrobial peptides. Constitutive activation of the system confers protection against CAMPs and daptomycin in the absence of a functional LiaFSR system and leads to persistence of cardiac microlesions in vivo. Moreover, changes in the lipid cell membrane environment alter CAMP susceptibility and expression of the MadRS system. Thus, we provide a framework supporting a multilayered envelope defense mechanism for resistance and survival coupled to virulence.

Host-derived reactive oxygen species trigger activation of the Candida albicans transcription regulator Rtg1/3.

The signals that denote mammalian host environments and dictate the activation of signaling pathways in human-associated microorganisms are often unknown. The transcription regulator Rtg1/3 in the human fungal pathogen Candida albicans is a crucial determinant of host colonization and pathogenicity. Rtg1/3's activity is controlled, in part, by shuttling the regulator between the cytoplasm and nucleus of the fungus. The host signal(s) that Rtg1/3 respond(s) to, however, have remained unclear. Here we report that neutrophil-derived reactive oxygen species (ROS) direct the subcellular localization of this C. albicans transcription regulator. Upon engulfment of Candida cells by human or mouse neutrophils, the regulator shuttles to the fungal nucleus. Using genetic and chemical approaches to disrupt the neutrophils' oxidative burst, we establish that the oxidants produced by the NOX2 complex-but not the oxidants generated by myeloperoxidase-trigger Rtg1/3's migration to the nucleus. Furthermore, screening a collection of C. albicans kinase deletion mutants, we implicate the MKC1 signaling pathway in the ROS-dependent regulation of Rtg1/3 in this fungus. Finally, we show that Rtg1/3 contributes to C. albicans virulence in the nematode Caenorhabditis elegans in an ROS-dependent manner as the rtg1 and rtg3 mutants display virulence defects in wild-type but not in ROS deficient worms. Our findings establish NOX2-derived ROS as a key signal that directs the activity of the pleiotropic fungal regulator Rtg1/3.

Body composition and functional capacity in patients with Crohn's disease using Infliximab / Composição corporal e capacidade funcional de pacientes com doença de Crohn em uso de Infliximabe

Rationale: the use of anti-TNFα therapy, such as Infliximab (IFX), in patients with Chron's disease (CD) can lead to changes in body composition. Objective: to evaluate the body composition and functional capacity of patients with CD. Method: Cross-sectional study with patients with CD in clinical remission using IFX. For anthropometric evaluation, it was measured: weight, height and waist circumference; functional capacity by the hand grip strength test and body composition by bioelectric impedance. After that, the fat-free mass index and body fat index were calculated. Continouns variables were analyzed by Pearson or Spearman coefficient. For the multiple linear regression model, the time of use of IFX was used as a dependent variable and waist circumference, fat-free mass index, phase angle and handgrip strength were used as independent variables. Results: forty-three patients were evaluated, with an average of 43.1± 13.5 years of age. Of the total, 44.2% were overweight and 44.2% had increased waist circumference, 58.1% were classified with high to very high fat-free mass, 30.2% were below the adequacy parameter for fat-free mass index and 11.6% had reduced functional capacity. Conclusion: overweight, as well as increased waist circumference and body fat, is common in CD patients in clinical remission using Infliximab. Most patients had preserved functional capacity, however there wasn't association with time of use of IFX.

Introdução: o uso de terapia anti-TNFα, como o Infliximabe (IFX), em pacientes com doença de Chron (DC) pode levar a alterações na composição corporal. Objetivo: avaliar a composição corporal e capacidade funcional de pacientes com DC. Metodologia: estudo transversal com pacientes com DC em remissão clínica, em uso de IFX. Foi realizada avaliação antropométrica (peso, estatura e circunferência da cintura); avaliação de capacidade funcional (teste de força de pressão manual); e avaliação de composição corporal (impedância bioelétrica) com cálculo do índice de massa livre de gordura e índice de gordura corporal. Variáveis contínuas foram analisadas pelo coeficiente de correlação de Pearson ou Spearman. Para o modelo de regressão linear múltipla, o tempo de uso do IFX foi utilizado como variável dependente e circunferência da cintura, índice de massa magra, ângulo de fase e força de preensão manual foram utilizados como variáveis independentes. Resultados: foram avaliados 43 pacientes, com média de idade de 43,1± 13,5 anos. 44,2% estavam acima do peso e 44,2% possuíam circunferência da cintura aumentada, 58,1% foram classificados com índice de gordura corporal de alto a muito alto, 30,2% estavam abaixo do parâmetro de adequação para o índice de massa livre de gordura e 11,6% apresentaram capacidade funcional reduzida. Conclusão: o excesso de peso e o aumento de circunferência da cintura e gordura corporal é frequente em pacientes com DC em remissão clínica e em uso de IFX. A maioria dos pacientes apresentou capacidade funcional preservada, porém não houve associação com o tempo de uso do IFX.

COVID-19 impacts on household solid waste generation in six Latin American countries: a participatory approach.

The COVID-19 pandemic has greatly impacted the Americas, the continent with the highest number of COVID-related deaths according to WHO statistics. In Latin America, strict confinement conditions at the beginning of the pandemic put recycling activity to a halt and augmented the consumption of plastic as a barrier to stop the spread of the virus. The lack of data to understand waste management dynamics complicates waste management strategy adjustments aimed at coping with COVID-19. As a novel contribution to the waste management data gap for Latin America, this study uses a virtual and participatory methodology that collects and generates information on household solid waste generation and composition. Data was collected between June and November 2021 in six countries in Latin America, with a total of 503 participants. Participants indicated that the pandemic motivated them to initiate or increase waste reduction (41%), waste separation (40%), and waste recovery (33%) activities. Forty-three percent of participants perceived an increase in total volume of their waste; however, the quantitative data showed a decrease in household waste generation in Peru (-31%), Honduras (-25%), and Venezuela (-82%). No changes in waste composition were observed. Despite the limited sample size, this data provides a much-needed approximation of household waste generation and composition in the pandemic situation during 2021.

Structural and functional analysis of EntV reveals a 12 amino acid fragment protective against fungal infections.

Fungal pathogens are a continuing challenge due to few effective antifungals and a rise in resistance. In previous work, we described the inhibition of Candida albicans virulence following exposure to the 68 amino acid bacteriocin, EntV, secreted by Enterococcus faecalis. Here, to optimize EntV as a potential therapeutic and better understand its antifungal features, an X-ray structure is obtained. The structure consists of six alpha helices enclosing a seventh 16 amino acid helix (α7). The individual helices are tested for antifungal activity using in vitro and nematode infection assays. Interestingly, α7 retains antifungal, but not antibacterial activity and is also effective against Candida auris and Cryptococcus neoformans. Further reduction of α7 to 12 amino acids retains full antifungal activity, and excellent efficacy is observed in rodent models of C. albicans oropharyngeal, systemic, and venous catheter infections. Together, these results showcase EntV-derived peptides as promising candidates for antifungal therapeutic development.

An Open-Access Data Platform: Global Nutrition and Health Atlas (GNHA).

The rapid development of nutrition science is embracing digital transformation to generate large amounts of data. Precision nutrition and "Big Data" place increasing demand for data repositories and visualization, which enhances the digital transformation. We defined the need for an integrated nutrition data platform as a web-based platform that can collect, store, track, analyze, monitor, and visually display key metrics in nutrition and health while allowing users to interact with visuals and download data provided in the platform. Interactive dashboards create new opportunities for scholars and practitioners to generate and test hypotheses. We present the development and implementation of the Global Nutrition and Health Atlas (GNHA; https://sites.tufts.edu/gnha/), an open-access online platform covering nutrition and health data with 26 themes and 500+ indicators from 190+ countries up to 30 y. We view GNHA as an interactive tool aiming to share information and perspectives and foster collaborations and innovations.

Food and Nutrition Systems Dashboards: A Systematic Review.

The rapid expansion of food and nutrition information requires new ways of data sharing and dissemination. Interactive platforms integrating data portals and visualization dashboards have been effectively utilized to describe, monitor, and track information related to food and nutrition; however, a comprehensive evaluation of emerging interactive systems is lacking. We conducted a systematic review on publicly available dashboards using a set of 48 evaluation metrics for data integrity, completeness, granularity, visualization quality, and interactivity based on 4 major principles: evidence, efficiency, emphasis, and ethics. We evaluated 13 dashboards, summarized their characteristics, strengths, and limitations, and provided guidelines for developing nutrition dashboards. We applied mixed effects models to summarize evaluation results adjusted for interrater variability. The proposed metrics and evaluation principles help to improve data standardization and harmonization, dashboard performance and usability, broaden information and knowledge sharing among researchers, practitioners, and decision makers in the field of food and nutrition, and accelerate data literacy and communication.

HOW IS THE DIET QUALITY OF PATIENTS WITH CROHN'S DISEASE IN CLINICAL REMISSION USING INFLIXIMAB?

BACKGROUND: A healthy diet is recommended for patients with Crohn's disease (CD) in remission. OBJECTIVE: To evaluate the diet quality of patients with CD. METHODS: Cross-sectional study with patients with CD and clinical remission using the biological agent infliximab. The diet quality was assessed using the Diet Quality Index-Revised (DQI-R). DQI-R was calculated based on 24-hour dietary recalls (24HR), being classified as "inadequate diet" (≤40 points), "diet requiring modifications" (41 to 64 points) and "healthy diet" (≥65 points). Weight, height and waist circumference (WC) of patients were assessed. For comparison between groups, Student's t-test or Mann-Whitney was used. For correlation between continuous variables, Pearson or Spearman coefficient was used. Values of P<0.05 indicated statistical significance. RESULTS: A total of 43 patients participated in the study. The final DQI-R score was 49.1 points - "diet requiring modifications". No patient received the classification of "healthy diet" (maximum score =59.7), 55.8% presented "diet requiring modifications" and 44.2% "inadequate diet". When comparing the "inadequate diet" and "diet requiring modifications" groups, a lower mean age was observed in the "inadequate diet" group (37.6±14.8 versus 47.4±10.5 y, P=0.02). It was found that 44.2% of the patients were overweight (body mass index [BMI] ≥25 kg/m²) and had increased WC (women: WC ≥80 cm and men: WC ≥94 cm). A positive correlation was found between the final DQI-R score and BMI (P=0.046; r=0.346). CONCLUSION: Patients with CD in clinical remission using infliximab are not adopting a diet considered healthy, which points to the need for an individualized nutritional approach.

Como está a qualidade da dieta de pacientes com doença de Crohn em remissão clínica e em uso de infliximabe? / How is the diet quality of patients with crohn's disease in clinical remission using infliximab?

ABSTRACT BACKGROUND: A healthy diet is recommended for patients with Crohn's disease (CD) in remission. OBJECTIVE: To evaluate the diet quality of patients with CD. METHODS: Cross-sectional study with patients with CD and clinical remission using the biological agent infliximab. The diet quality was assessed using the Diet Quality Index-Revised (DQI-R). DQI-R was calculated based on 24-hour dietary recalls (24HR), being classified as "inadequate diet" (≤40 points), "diet requiring modifications" (41 to 64 points) and "healthy diet" (≥65 points). Weight, height and waist circumference (WC) of patients were assessed. For comparison between groups, Student's t-test or Mann-Whitney was used. For correlation between continuous variables, Pearson or Spearman coefficient was used. Values of P<0.05 indicated statistical significance. RESULTS: A total of 43 patients participated in the study. The final DQI-R score was 49.1 points - "diet requiring modifications". No patient received the classification of "healthy diet" (maximum score =59.7), 55.8% presented "diet requiring modifications" and 44.2% "inadequate diet". When comparing the "inadequate diet" and "diet requiring modifications" groups, a lower mean age was observed in the "inadequate diet" group (37.6±14.8 versus 47.4±10.5 y, P=0.02). It was found that 44.2% of the patients were overweight (body mass index [BMI] ≥25 kg/m²) and had increased WC (women: WC ≥80 cm and men: WC ≥94 cm). A positive correlation was found between the final DQI-R score and BMI (P=0.046; r=0.346). CONCLUSION: Patients with CD in clinical remission using infliximab are not adopting a diet considered healthy, which points to the need for an individualized nutritional approach.

RESUMO CONTEXTO: É recomendado alimentação saudável para pacientes com doença de Crohn (DC) em remissão. OBJETIVO: Avaliar a qualidade da dieta de pacientes com DC. MÉTODOS: Estudo transversal com pacientes com DC em remissão clínica e em uso do imunobiológico infliximabe. A qualidade da dieta foi avaliada pelo índice de qualidade da dieta revisado (IQD-R). O IQD-R foi calculado a partir do recordatório 24 horas, sendo classificado em "dieta inadequada" (≤40 pontos), "dieta que requer modificações" (41 a 64 pontos) e "dieta saudável" (≥65 pontos). Os pacientes foram avaliados quanto ao peso, altura e circunferência da cintura (CC). Para comparação entre grupos foi utilizado o test-t de Student ou Mann-Whitney. Para correlação entre variáveis contínuas foi utilizado o coeficiente de Pearson ou Spearman. Valores de P<0,05 indicaram significância estatística. RESULTADOS: Participaram do estudo 43 pacientes. A pontuação final do IQD-R foi de 49,1 pontos - "dieta que requer modificações". Nenhum paciente recebeu a classificação de "dieta saudável" (pontuação máxima =59,7), 55,8% apresentaram "dieta que requer modificações" e 44,2% "dieta inadequada". Ao comparar os grupos "dieta inadequada" e "dieta que requer modificações", foi observado menor média de idade no grupo "dieta inadequada" (37,6±14,8 versus 47,4±10,5 anos, P=0,02). Verificou-se que 44,2% dos pacientes estavam acima do peso (índice de massa corporal (IMC) ≥25 kg/m²) e possuíam CC aumentada (mulheres: CC ≥80 cm e homens: CC ≥94 cm). Foi encontrada correlação positiva entre a pontuação final do IQD-R e o IMC (P=0,046; r=0,346). CONCLUSÃO: Os pacientes com DC em remissão clínica e em uso de infliximabe não estão adotando dieta com qualidade considerada saudável o que aponta a necessidade de abordagem nutricional individualizada.

Ribonuclease J-Mediated mRNA Turnover Modulates Cell Shape, Metabolism and Virulence in Corynebacterium diphtheriae.

Controlled RNA degradation is a crucial process in bacterial cell biology for maintaining proper transcriptome homeostasis and adaptation to changing environments. mRNA turnover in many Gram-positive bacteria involves a specialized ribonuclease called RNase J (RnJ). To date, however, nothing is known about this process in the diphtheria-causative pathogen Corynebacterium diphtheriae, nor is known the identity of this ribonuclease in this organism. Here, we report that C. diphtheriae DIP1463 encodes a predicted RnJ homolog, comprised of a conserved N-terminal ß-lactamase domain, followed by ß-CASP and C-terminal domains. A recombinant protein encompassing the ß-lactamase domain alone displays 5'-exoribonuclease activity, which is abolished by alanine-substitution of the conserved catalytic residues His186 and His188. Intriguingly, deletion of DIP1463/rnj in C. diphtheriae reduces bacterial growth and generates cell shape abnormality with markedly augmented cell width. Comparative RNA-seq analysis revealed that RnJ controls a large regulon encoding many factors predicted to be involved in biosynthesis, regulation, transport, and iron acquisition. One upregulated gene in the ∆rnj mutant is ftsH, coding for a membrane protease (FtsH) involved in cell division, whose overexpression in the wild-type strain also caused cell-width augmentation. Critically, the ∆rnj mutant is severely attenuated in virulence in a Caenorhabditis elegans model of infection, while the FtsH-overexpressing and toxin-less strains exhibit full virulence as the wild-type strain. Evidently, RNase J is a key ribonuclease in C. diphtheriae that post-transcriptionally influences the expression of numerous factors vital to corynebacterial cell physiology and virulence. Our findings have significant implications for basic biological processes and mechanisms of corynebacterial pathogenesis.

Transcriptome analysis of Caenorhabditis elegans lacking heme peroxidase SKPO-1 reveals an altered response to Enterococcus faecalis.

The nematode Caenorhabditis elegans is commonly used as a model organism in studies of the host immune response. The worm encodes twelve peroxidase-cyclooxygenase superfamily members, making it an attractive model in which to study the functions of heme peroxidases. In previous work, loss of one of these peroxidases, SKPO-1 (ShkT-containing peroxidase), rendered C. elegans more sensitive to the human, Gram-positive pathogen Enterococcus faecalis. SKPO-1 was localized to the hypodermis of the animals where it also affected cuticle development as indicated by a morphological phenotype called "dumpy." In this work, a better understanding of how loss of skpo-1 impacts both sensitivity to pathogen as well as cuticle development was sought by subjecting a deletion mutant of skpo-1 to transcriptome analysis using RNA sequencing following exposure to control (Escherichia coli) and pathogenic (E. faecalis) feeding conditions. Loss of skpo-1 caused a general upregulation of genes encoding collagens and other proteins related to cuticle development. On E. faecalis, these animals also failed to upregulate guanylyl cyclases that are often involved in environmental sensing. Hoechst straining revealed increased permeability of the cuticle and atomic force microscopy exposed the misalignment of the cuticular annuli and furrows. These findings provide a basis for better understanding of the morphological as well as the pathogen sensitivity phenotypes associated with loss of SKPO-1 function.

Cardiac Microlesions Form During Severe Bacteremic Enterococcus faecalis Infection.

Enterococcus  faecalis is a significant cause of hospital-acquired bacteremia. Herein, the discovery is reported that cardiac microlesions form during severe bacteremic E. faecalis infection in mice. The cardiac microlesions were identical in appearance to those formed by Streptococcus pneumoniae during invasive pneumococcal disease. However, E. faecalis does not encode the virulence determinants implicated in pneumococcal microlesion formation. Rather, disulfide bond forming protein A (DsbA) was found to be required for E. faecalis virulence in a Caenorhabditis elegans model and was necessary for efficient cardiac microlesion formation. Furthermore, E. faecalis promoted cardiomyocyte apoptotic and necroptotic cell death at sites of microlesion formation. Additionally, loss of DsbA caused an increase in proinflammatory cytokines, unlike the wild-type strain, which suppressed the immune response. In conclusion, we establish that E. faecalis is capable of forming cardiac microlesions and identify features of both the bacterium and the host response that are mechanistically involved.

Can oral nutritional supplements increase energy and protein intake among hospitalized patients? / ¿Los suplementos nutricionales orales pueden aumentar la energía y la proteína en pacientes hospitalizados?

ABSTRACT Background: Oral nutritional supplements aim at offsetting dietary deficits and helping to meet energy and protein targets. Due to the absence of data about their role in food intake, it is necessary to evaluate the contribution of these products to the estimated needs of hospitalized patients. Methods: This is a prospective longitudinal study with hospitalized patients over 18 years of age, admitted to a public university hospital, who were given oral nutritional supplements, according to clinical guidelines. Food intake was quantified throughout the period such products were prescribed. Results: 805-day food intake follow-up and record of 128 patients, who took supplements for 6.4 days on average. The use of nutritional supplements demonstrated a significant contribution to the input of both energy (1576 kcal/day versus 1263 kcal/day, p<0.001) and protein (68.7 g/day versus 50.3 g/day, p<0.001). Conclusions: Nutritional supplements help increase food intake and achieve nutritional goals when prescribed in a hospital setting.

RESUMEN Antecedentes: los suplementos nutricionales orales tienen como objetivo compensar los déficits dietéticos y ayudar a cumplir los objetivos de energía y proteínas. Debido a la ausencia de datos sobre su papel en la ingesta de alimentos, es necesario evaluar la contribución de estos productos a las necesidades estimadas de los pacientes hospitalizados. Métodos: Este es un estudio longitudinal prospectivo con pacientes hospitalizados mayores de 18 años, ingresados en un hospital universitario público, que recibieron suplementos nutricionales orales, según la derivación clínica. La ingesta de alimentos se cuantificó durante todo el período en que se prescribieron dichos productos. Resultados: seguimiento de la ingesta alimentaria de 805 días y registro de 128 pacientes, que tomaron suplementos durante 6,4 días en promedio. El uso de suplementos nutricionales demostró una contribución significativa al aporte de energía (1576 kcal/día versus 1263 kcal/día, p< 0,001) y proteína (68,7 g/día versus 50,3 g/día, p<0,001). Conclusiones: los suplementos nutricionales ayudan a aumentar la ingesta de alimentos y alcanzar objetivos nutricionales cuando se prescriben en un entorno hospitalario.

Antimicrobial sensing coupled with cell membrane remodeling mediates antibiotic resistance and virulence in Enterococcus faecalis.

Bacteria have developed several evolutionary strategies to protect their cell membranes (CMs) from the attack of antibiotics and antimicrobial peptides (AMPs) produced by the innate immune system, including remodeling of phospholipid content and localization. Multidrug-resistant Enterococcus faecalis, an opportunistic human pathogen, evolves resistance to the lipopeptide daptomycin and AMPs by diverting the antibiotic away from critical septal targets using CM anionic phospholipid redistribution. The LiaFSR stress response system regulates this CM remodeling via the LiaR response regulator by a previously unknown mechanism. Here, we characterize a LiaR-regulated protein, LiaX, that senses daptomycin or AMPs and triggers protective CM remodeling. LiaX is surface exposed, and in daptomycin-resistant clinical strains, both LiaX and the N-terminal domain alone are released into the extracellular milieu. The N-terminal domain of LiaX binds daptomycin and AMPs (such as human LL-37) and functions as an extracellular sentinel that activates the cell envelope stress response. The C-terminal domain of LiaX plays a role in inhibiting the LiaFSR system, and when this domain is absent, it leads to activation of anionic phospholipid redistribution. Strains that exhibit LiaX-mediated CM remodeling and AMP resistance show enhanced virulence in the Caenorhabditis elegans model, an effect that is abolished in animals lacking an innate immune pathway crucial for producing AMPs. In conclusion, we report a mechanism of antibiotic and AMP resistance that couples bacterial stress sensing to major changes in CM architecture, ultimately also affecting host-pathogen interactions.

Spatiotemporal Patterns of Cholera Hospitalization in Vellore, India.

Systematically collected hospitalization records provide valuable insight into disease patterns and support comprehensive national infectious disease surveillance networks. Hospitalization records detailing patient's place of residence (PoR) can be utilized to better understand a hospital's case load and strengthen surveillance among mobile populations. This study examined geographic patterns of patients treated for cholera at a major hospital in south India. We abstracted 1401 laboratory-confirmed cases of cholera between 2000-2014 from logbooks and electronic health records (EHRs) maintained by the Christian Medical College (CMC) in Vellore, Tamil Nadu, India. We constructed spatial trend models and identified two distinct clusters of patient residence-one around Vellore (836 records (61.2%)) and one in Bengal (294 records (21.5%)). We further characterized differences in peak timing and disease trend among these clusters to identify differences in cholera exposure among local and visiting populations. We found that the two clusters differ by their patient profiles, with patients in the Bengal cluster being most likely older males traveling to Vellore. Both clusters show well-aligned seasonal peaks in mid-July, only one week apart, with similar downward trend and proportion of predominant O1 serotype. Large hospitals can thus harness EHRs for surveillance by utilizing patients' PoRs to study disease patterns among resident and visitor populations.

Spatiotemporal and Demographic Trends and Disparities in Cardiovascular Disease Among Older Adults in the United States Based on 181 Million Hospitalization Records.

Background The US population is aging, with concurrent increases in cardiovascular disease (CVD) burdens; however, spatiotemporal and demographic trends in CVD incidence in the US elderly have not been investigated in detail. This study aims to characterize trends from 1991 to 2014 in CVD hospitalizations among US Medicare beneficiaries, aged 65+ years, by single year of age/sex/race/state using records from the US Centers for Medicare & Medicaid, covering 98% of older Americans. Methods and Results We abstracted 181 202 758 US Centers for Medicare & Medicaid hospitalization records indicating CVD in any of 10 diagnosis codes; tabulated total cases of CVD by sex, age, race, state, and calendar year (1991-2014); and normalized hospitalization counts to standardize over data batches. Stratum-specific hospitalization rates were calculated using US Centers for Medicare & Medicaid records and US Census population counts; a cubic polynomial function was fit to year-specific distributions of rates by single year of age. Nationwide, CVD-related hospitalization rates increased from 1991 to 2014. Differences between hospitalization rates at age 65 and 66 years, representing magnitude of healthcare deferral until Medicare onset, increased by 7.49 per 100 people 1991 to 2006 overall, and were largest among blacks and Native Americans. Rates of CVD hospitalizations were consistently highest in the Midwest/Deep South. Evidence of misclassification of race/ethnicity in US Centers for Medicare & Medicaid hospitalization records in the 1990s was noted. Conclusions Trends in CVD-related hospitalization rates among older Americans highlight the essential need for targeted policies to reduce CVD burdens, to improve reporting of race/ethnicity in large administrative databases, and to enhance access to affordable healthcare.

Antifungal Activity of the Enterococcus faecalis Peptide EntV Requires Protease Cleavage and Disulfide Bond Formation.

Enterococcus faecalis, a Gram-positive bacterium, and Candida albicans, a polymorphic fungus, are common constituents of the microbiome as well as increasingly problematic causes of infections. Interestingly, we previously showed that these two species antagonize each other's virulence and that E. faecalis inhibition of C. albicans was specifically mediated by EntV. EntV is a bacteriocin encoded by the entV (ef1097) locus that reduces C. albicans virulence and biofilm formation by inhibiting hyphal morphogenesis. In this report, we studied the posttranslational modifications necessary for EntV antifungal activity. First, we show that the E. faecalis secreted enzyme gelatinase (GelE) is responsible for cleaving EntV into its 68-amino-acid, active form and that this process does not require the serine protease SprE. Furthermore, we demonstrate that a disulfide bond that forms within EntV is necessary for antifungal activity. Abrogating this bond by chemical treatment or genetic modification rendered EntV inactive against C. albicans Moreover, we identified the likely catalyst of this disulfide bond, a previously uncharacterized thioredoxin within the E. faecalis genome called DsbA. Loss of DsbA, or disruption of its redox-active cysteines, resulted in loss of EntV antifungal activity. Finally, we show that disulfide bond formation is not a prerequisite for cleavage; EntV cleavage proceeded normally in the absence of DsbA. In conclusion, we present a model in which following secretion, EntV undergoes disulfide bond formation by DsbA and cleavage by GelE in order to generate a peptide capable of inhibiting C. albicansIMPORTANCEEnterococcus faecalis and Candida albicans are among the most important and problematic pathobionts, organisms that normally are harmless commensals but can cause dangerous infections in immunocompromised hosts. In fact, both organisms are listed by the Centers for Disease Control and Prevention as serious global public health threats stemming from the increased prevalence of antimicrobial resistance. The rise in antifungal resistance is of particular concern considering the small arsenal of currently available therapeutics. EntV is a peptide with antifungal properties, and it, or a similar compound, could be developed into a therapeutic alternative, either alone or in combination with existing agents. However, to do so requires understanding what properties of EntV are necessary for its antifungal activity. In this work, we studied the posttranslational processing of EntV and what modifications are necessary for inhibition of C. albicans in order to fill this gap in knowledge.