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BMJ Open May 2024This study aimed to describe the clinical characteristics of adults with suspected acute community-acquired pneumonia (CAP) on hospitalisation, evaluate their prediction...
Community-acquired pneumonia: use of clinical characteristics of acutely admitted patients for the development of a diagnostic model - a cross-sectional multicentre study.
OBJECTIVES
This study aimed to describe the clinical characteristics of adults with suspected acute community-acquired pneumonia (CAP) on hospitalisation, evaluate their prediction performance for CAP and compare the performance of the model to the initial assessment of the physician.
DESIGN
Cross-sectional, multicentre study.
SETTING
The data originated from the INfectious DisEases in Emergency Departments study and were collected prospectively from patient interviews and medical records. The study included four Danish medical emergency departments (EDs) and was conducted between 1 March 2021 and 28 February 2022.
PARTICIPANTS
A total of 954 patients admitted with suspected infection were included in the study.
PRIMARY AND SECONDARY OUTCOME
The primary outcome was CAP diagnosis assessed by an expert panel.
RESULTS
According to expert evaluation, CAP had a 28% prevalence. 13 diagnostic predictors were identified using least absolute shrinkage and selection operator regression to build the prediction model: dyspnoea, expectoration, cough, common cold, malaise, chest pain, respiratory rate (>20 breaths/min), oxygen saturation (<96%), abnormal chest auscultation, leucocytes (<3.5×10/L or >8.8×10/L) and neutrophils (>7.5×10/L). C reactive protein (<20 mg/L) and having no previous event of CAP contributed negatively to the final model. The predictors yielded good prediction performance for CAP with an area under the receiver-operator characteristic curve (AUC) of 0.85 (CI 0.77 to 0.92). However, the initial diagnosis made by the ED physician performed better, with an AUC of 0.86 (CI 84% to 89%).
CONCLUSION
Typical respiratory symptoms combined with abnormal vital signs and elevated infection biomarkers were predictors for CAP on admission to an ED. The clinical value of the prediction model is questionable in our setting as it does not outperform the clinician's assessment. Further studies that add novel diagnostic tools and use imaging or serological markers are needed to improve a model that would help diagnose CAP in an ED setting more accurately.
TRIAL REGISTRATION NUMBER
NCT04681963.
Topics: Humans; Community-Acquired Infections; Cross-Sectional Studies; Male; Female; Middle Aged; Aged; Pneumonia; Emergency Service, Hospital; Hospitalization; Denmark; Adult; ROC Curve; Prospective Studies; C-Reactive Protein
PubMed: 38816044
DOI: 10.1136/bmjopen-2023-079123 -
Cellular and Molecular Gastroenterology... May 2024Type 2 innate lymphoid cells (ILC2s) and interleukin-13 (IL-13) promote the onset of spasmolytic polypeptide-expressing metaplasia (SPEM) cells. However, little is known...
BACKGROUND & AIMS
Type 2 innate lymphoid cells (ILC2s) and interleukin-13 (IL-13) promote the onset of spasmolytic polypeptide-expressing metaplasia (SPEM) cells. However, little is known about molecular effects of IL-13 in SPEM cells. We now sought to establish a reliable organoid model, Meta1 gastroids, to model SPEM cells in vitro. We evaluated cellular and molecular effects of ILC2s and IL-13 on maturation and proliferation of SPEM cells.
METHODS
We performed single-cell RNA sequencing to characterize Meta1 gastroids, which were derived from stomachs of Mist1-Kras transgenic mice that displayed pyloric metaplasia. Cell sorting was used to isolate activated ILC2s from stomachs of IL-13-tdTomato reporter mice treated with L635. Three-dimensional co-culture was used to determine the effects of ILC2s on Meta1 gastroids. Mouse normal or metaplastic (Meta1) and human metaplastic gastroids were cultured with IL-13 to evaluate cell responses. Air-Liquid Interface culture was performed to test long-term culture effects of IL-13. In silico analysis determined possible STAT6-binding sites in gene promoter regions. STAT6 inhibition was performed to corroborate STAT6 role in SPEM cells maturation.
RESULTS
Meta1 gastroids showed the characteristics of SPEM cell lineages in vitro even after several passages. We demonstrated that co-culture with ILC2s or IL-13 treatment can induce phosphorylation of STAT6 in Meta1 and normal gastroids and promote the maturation and proliferation of SPEM cell lineages. IL-13 upregulated expression of mucin-related proteins in human metaplastic gastroids. Inhibition of STAT6 blocked SPEM-related gene expression in Meta1 gastroids and maturation of SPEM in both normal and Meta1 gastroids.
CONCLUSIONS
IL-13 promotes the maturation and proliferation of SPEM cells consistent with gastric mucosal regeneration.
PubMed: 38815928
DOI: 10.1016/j.jcmgh.2024.101366 -
The Journal of Biological Chemistry May 2024Infiltration of monocyte-derived cells to sites of infection and injury is greater in males than in females, due in part, to increased chemotaxis, the process of...
Infiltration of monocyte-derived cells to sites of infection and injury is greater in males than in females, due in part, to increased chemotaxis, the process of directed cell movement toward a chemical signal. The mechanisms governing sexual dimorphism in chemotaxis are not known. We hypothesized a role for the store-operated calcium entry (SOCE) pathway in regulating chemotaxis by modulating leading and trailing edge membrane dynamics. We measured the chemotactic response of bone marrow derived macrophages (BMDMs) migrating towards complement component 5a (C5a). Chemotactic ability was dependent on sex and inflammatory phenotype (M0, M1, M2), and correlated with SOCE. Notably, females exhibited a significantly lower magnitude of SOCE than males. When we knocked out the SOCE gene, stromal interaction molecule 1 (STIM1), it eliminated SOCE and equalized chemotaxis across both sexes. Analysis of membrane dynamics at the leading and trailing edges showed that STIM1 influences chemotaxis by facilitating retraction of the trailing edge. Using BTP2 to pharmacologically inhibit SOCE mirrored the effects of STIM1 knockout, demonstrating a central role of STIM/Orai-mediated calcium signaling. Importantly, by monitoring the recruitment of adoptively transferred monocytes in an in vivo model of peritonitis, we show that increased infiltration of male monocytes during infection is dependent on STIM1. These data support a model in which STIM1-dependent SOCE is necessary and sufficient for mediating the sex difference in monocyte recruitment and macrophage chemotactic ability by regulating trailing edge dynamics.
PubMed: 38815866
DOI: 10.1016/j.jbc.2024.107422 -
Redox Biology May 2024Cysteine, the rate-controlling amino acid in cellular glutathione synthesis is imported as cystine, by the cystine/glutamate antiporter, xCT, and subsequently reduced to...
Cysteine, the rate-controlling amino acid in cellular glutathione synthesis is imported as cystine, by the cystine/glutamate antiporter, xCT, and subsequently reduced to cysteine. As glutathione redox is important in muscle regeneration in aging, we hypothesized that xCT exerts upstream control over skeletal muscle glutathione redox, metabolism and regeneration. Bioinformatic analyses of publicly available datasets revealed that expression levels of xCT and GSH-related genes are inversely correlated with myogenic differentiation genes. Muscle satellite cells (MuSCs) isolated from Slc7a11 mice, which harbour a mutation in the Slc7a11 gene encoding xCT, required media supplementation with 2-mercaptoethanol to support cell proliferation but not myotube differentiation, despite persistently lower GSH. Slc7a11 primary myotubes were larger compared to WT myotubes, and also exhibited higher glucose uptake and cellular oxidative capacities. Immunostaining of myogenic markers (Pax7, MyoD, and myogenin) in cardiotoxin-damaged tibialis anterior muscle fibres revealed greater MuSC activation and commitment to differentiation in Slc7a11 muscle compared to WT mice, culminating in larger myofiber cross-sectional areas at 21 days post-injury. Slc7a11 mice subjected to a 5-week exercise training protocol demonstrated enhanced insulin tolerance compared to WT mice, but blunted muscle mitochondrial biogenesis and respiration in response to exercise training. Our results demonstrate that the absence of xCT inhibits cell proliferation but promotes myotube differentiation by regulating cellular metabolism and glutathione redox. Altogether, these results support the notion that myogenesis is a redox-regulated process and may help inform novel therapeutic approaches for muscle wasting and dysfunction in aging and disease.
PubMed: 38815331
DOI: 10.1016/j.redox.2024.103213 -
PLoS Pathogens May 2024The influenza A virus (IAV) consists of 8 single-stranded, negative-sense viral RNA (vRNA) segments. After infection, vRNA is transcribed, replicated, and wrapped by...
The influenza A virus (IAV) consists of 8 single-stranded, negative-sense viral RNA (vRNA) segments. After infection, vRNA is transcribed, replicated, and wrapped by viral nucleoprotein (NP) to form viral ribonucleoprotein (vRNP). The transcription, replication, and nuclear export of the viral genome are regulated by the IAV protein, NS2, which is translated from spliced mRNA transcribed from viral NS vRNA. This splicing is inefficient, explaining why NS2 is present in low abundance after IAV infection. The levels of NS2 and its subsequent accumulation are thought to influence viral RNA replication and vRNP nuclear export. Here we show that NS2 is ubiquitinated at the K64 and K88 residues by K48-linked and K63-linked polyubiquitin (polyUb) chains, leading to the degradation of NS2 by the proteasome. Additionally, we show that a host deubiquitinase, OTUB1, can remove polyUb chains conjugated to NS2, thereby stabilizing NS2. Accordingly, knock down of OTUB1 by siRNA reduces the nuclear export of vRNP, and reduces the overall production of IAV. These results collectively demonstrate that the levels of NS2 in IAV-infected cells are regulated by a ubiquitination-deubiquitination system involving OTUB1 that is necessary for optimal IAV replication.
PubMed: 38814988
DOI: 10.1371/journal.ppat.1012279 -
PLoS Pathogens May 2024Toxoplasma gondii is a foodborne pathogen that can cause severe and life-threatening infections in fetuses and immunocompromised patients. Felids are its only definitive...
Toxoplasma gondii is a foodborne pathogen that can cause severe and life-threatening infections in fetuses and immunocompromised patients. Felids are its only definitive hosts, and a wide range of animals, including humans, serve as intermediate hosts. When the transmissible bradyzoite stage is orally ingested by felids, they transform into merozoites that expand asexually, ultimately generating millions of gametes for the parasite sexual cycle. However, bradyzoites in intermediate hosts differentiate exclusively to disease-causing tachyzoites, which rapidly disseminate throughout the host. Though tachyzoites are well-studied, the molecular mechanisms governing transitioning between developmental stages are poorly understood. Each parasite stage can be distinguished by a characteristic transcriptional signature, with one signature being repressed during the other stages. Switching between stages require substantial changes in the proteome, which is achieved in part by ubiquitination. F-box proteins mediate protein poly-ubiquitination by recruiting substrates to SKP1, Cullin-1, F-Box protein E3 ubiquitin ligase (SCF-E3) complexes. We have identified an F-box protein named Toxoplasma gondii F-Box Protein L2 (TgFBXL2), which localizes to distinct perinucleolar sites. TgFBXL2 is stably engaged in an SCF-E3 complex that is surprisingly also associated with a COP9 signalosome complex that negatively regulates SCF-E3 function. At the cellular level, TgFBXL2-depleted parasites are severely defective in centrosome replication and daughter cell development. Most remarkable, RNAseq data show that TgFBXL2 conditional depletion induces the expression of stage-specific genes including a a large cohort of genes necessary for sexual commitment. Together, these data suggest that TgFBXL2 is a latent guardian of stage specific gene expression in Toxoplasma and poised to remove conflicting proteins in response to an unknown trigger of development.
PubMed: 38814984
DOI: 10.1371/journal.ppat.1012269 -
PloS One 2024After its emergence in China, the coronavirus SARS-CoV-2 has swept the world, leading to global health crises with millions of deaths. COVID-19 clinical manifestations...
BACKGROUND
After its emergence in China, the coronavirus SARS-CoV-2 has swept the world, leading to global health crises with millions of deaths. COVID-19 clinical manifestations differ in severity, ranging from mild symptoms to severe disease. Although perturbation of metabolism has been reported as a part of the host response to COVID-19 infection, scarce data exist that describe stage-specific changes in host metabolites during the infection and how this could stratify patients based on severity.
METHODS
Given this knowledge gap, we performed targeted metabolomics profiling and then used machine learning models and biostatistics to characterize the alteration patterns of 50 metabolites and 17 blood parameters measured in a cohort of 295 human subjects. They were categorized into healthy controls, non-severe, severe and critical groups with their outcomes. Subject's demographic and clinical data were also used in the analyses to provide more robust predictive models.
RESULTS
The non-severe and severe COVID-19 patients experienced the strongest changes in metabolite repertoire, whereas less intense changes occur during the critical phase. Panels of 15, 14, 2 and 2 key metabolites were identified as predictors for non-severe, severe, critical and dead patients, respectively. Specifically, arginine and malonyl methylmalonyl succinylcarnitine were significant biomarkers for the onset of COVID-19 infection and tauroursodeoxycholic acid were potential biomarkers for disease progression. Measuring blood parameters enhanced the predictive power of metabolic signatures during critical illness.
CONCLUSIONS
Metabolomic signatures are distinctive for each stage of COVID-19 infection. This has great translation potential as it opens new therapeutic and diagnostic prospective based on key metabolites.
Topics: Humans; COVID-19; Machine Learning; Male; Female; Biomarkers; Middle Aged; Metabolomics; Adult; Severity of Illness Index; SARS-CoV-2; Aged; Metabolome
PubMed: 38814977
DOI: 10.1371/journal.pone.0302977 -
PloS One 2024Women living with HIV (WLWH) have high risk of developing cervical cancer. High- risk Human papillomavirus (hrHPV) is the single most important cause of cervical cancer....
BACKGROUND
Women living with HIV (WLWH) have high risk of developing cervical cancer. High- risk Human papillomavirus (hrHPV) is the single most important cause of cervical cancer. Vaccination for and early detection of pre-malignant cervical changes, through cervical cancer screening contributes to prevention of cervical cancer. This study sought to determine the prevalence of HPV among WLWH, genotypes present and the risk factors associated with cervical cancer development.
METHODS AND FINDINGS
An analytical cross-sectional study of 250 sexually active women aged 18 years and above, attending HIV clinic at a tertiary health facility in Accra. Demographic data collection and risk factor assessments were done using interviewer-administered questionnaire, and patient records. Cervical swabs were collected and tested for HPV using real-time PCR assays. Genotype analysis was performed on 92 samples. Descriptive statistics and logistic regression analysis were used to establish associations between hrHPV and risk factors among WLWH. Approximately 60% of study participants tested positive for HPV. The prevalence of hr-HPV among WLH was 44.4%. Factors identified to be protective of hrHPV were employment (AOR = 0.19, 95% CI = 0.06, 0.56, p = 0.003) and highly active antiretroviral therapy (HAART) Tenofovir-Lamivudine-Ritonavir-Lopinavir (TLRL) (AOR = 0.30, 95% CI = 0.09, 0.95, p = 0.04). Women with HIV diagnosis within 6 to10 years (AOR = 4.89, 95% CI = 1.05, 22.70, p = 0.043) and diagnosis >10 years (AOR = 8.25, 95% CI = 1.24, 54.84, p = 0.029) had higher odds of hrHPV. Approximately 25% of samples analysed tested positive for hr-HPV group 1 (genotypes 16, 18, 31, 33, 35, 39, 45,51, 52, 56, 58, 69) and 46.8% for multiple HPV genotypes.
CONCLUSION
A high prevalence of genotypes that include high risk genotypes 16 and 18 and multiple HPV infections was found among WLWH. Almost half of the women screened had high-risk HPV and were prone to cervical cancer without their knowledge. Regular HPV screening is recommended for high-risk patient groups.
Topics: Humans; Female; Adult; Papillomavirus Infections; HIV Infections; Risk Factors; Prevalence; Ghana; Cross-Sectional Studies; Middle Aged; Young Adult; Uterine Cervical Neoplasms; Adolescent; Papillomaviridae; Tertiary Care Centers
PubMed: 38814956
DOI: 10.1371/journal.pone.0303535 -
PloS One 2024The pathogenesis of anal sacculitis has not been extensively investigated, although atopic dogs seem to be predisposed to the disease. The aim of this study was... (Comparative Study)
Comparative Study
The pathogenesis of anal sacculitis has not been extensively investigated, although atopic dogs seem to be predisposed to the disease. The aim of this study was therefore to characterize and compare the bacterial microbiota and pro-inflammatory cytokines in the anal sacs of dogs from three groups (healthy dogs, untreated atopic dogs and atopic dogs receiving antipruritic treatment or allergen-specific immunotherapy) in order to determine whether changes could be at the origin of anal sacculitis in atopic dogs. Bacterial populations of anal sac secretions from fifteen healthy dogs, fourteen untreated and six treated atopic dogs were characterized by sequencing the V4 region of the 16S rRNA gene using Illumina technology. Proinflammatory cytokines were analyzed with the Luminex multiplex test. Community membership and structure were significantly different between the anal sacs of healthy and untreated atopic dogs (P = 0.002 and P = 0.003, respectively) and between those of untreated and treated atopic dogs (P = 0.012 and P = 0.017, respectively). However, the community structure was similar in healthy and treated atopic dogs (P = 0.332). Among the proinflammatory cytokines assessed, there was no significant difference between groups, except for interleukin 8 which was higher in the anal sacs of untreated atopic dogs compared to treated atopic dogs (P = 0.02), and tumor necrosis factor-alpha which was lower in the anal sacs of healthy dogs compared to treated atopic dogs (P = 0.04). These results reveal a dysbiosis in the anal sacs of atopic dogs, which may partially explain the predisposition of atopic dogs to develop bacterial anal sacculitis. Treatments received by atopic dogs (oclacitinib, desloratadine and allergen-specific immunotherapy) shift the microbiota of the anal sacs towards that of healthy dogs. Further studies are required to identify significant cytokines contributing to anal sacculitis in atopic dogs.
Topics: Animals; Dogs; Cytokines; Dog Diseases; Anal Sacs; Male; Microbiota; Female; RNA, Ribosomal, 16S; Dermatitis, Atopic; Case-Control Studies; Bacteria
PubMed: 38814946
DOI: 10.1371/journal.pone.0298361 -
PLoS Neglected Tropical Diseases May 2024Haemophilus ducreyi was historically known as the causative agent of chancroid, a sexually-transmitted disease causing painful genital ulcers endemic in many...
Haemophilus ducreyi was historically known as the causative agent of chancroid, a sexually-transmitted disease causing painful genital ulcers endemic in many low/middle-income nations. In recent years the species has been implicated as the causative agent of nongenital cutaneous ulcers affecting children of the South Pacific Islands and West African countries. Much is still unknown about the mechanism of H. ducreyi transmission in these areas, and recent studies have identified local insect species, namely flies, as potential transmission vectors. H. ducreyi DNA has been detected on the surface and in homogenates of fly species sampled from Lihir Island, Papua New Guinea. The current study develops a model system using Musca domestica, the common house fly, as a model organism to demonstrate proof of concept that flies are a potential vector for the transmission of viable H. ducreyi. Utilizing a green fluorescent protein (GFP)-tagged strain of H. ducreyi and three separate exposure methods, we detected the transmission of viable H. ducreyi by 86.11% ± 22.53% of flies sampled. Additionally, the duration of H. ducreyi viability was found to be directly related to the bacterial concentration, and transmission of H. ducreyi was largely undetectable within one hour of initial exposure. Push testing, Gram staining, and PCR were used to confirm the identity and presence of GFP colonies as H. ducreyi. This study confirms that flies are capable of mechanically transmitting viable H. ducreyi, illuminating the importance of investigating insects as vectors of cutaneous ulcerative diseases.
Topics: Animals; Houseflies; Haemophilus ducreyi; Chancroid; Papua New Guinea; Insect Vectors; Female; Male
PubMed: 38814945
DOI: 10.1371/journal.pntd.0012194