Association and temporal sequence of pneumonia and gastrointestinal bleeding after acute ischemic stroke.

BACKGROUND: Stroke-associated pneumonia (SAP) and gastrointestinal bleeding (GIB) are common medical complications after stroke. The previous study suggested a strong association between SAP and GIB after stroke. However, little is known about the time sequence of SAP and GIB. In the present study, we aimed to verify the association and clarify the temporal sequence of SAP and GIB after ischemic stroke. METHODS: Patients with ischemic stroke from in-hospital Medical Complication after Acute Stroke study were analyzed. Data on occurrences of SAP and GIB during hospitalization and the intervals from stroke onset to diagnosis of SAP and GIB were collected. Multiple logistic regression was used to evaluate the association between SAP and GIB. Kruskal-Wallis test was used to compare the time intervals from stroke onset to diagnosis of SAP and GIB. RESULTS: A total of 1129 patients with ischemic stroke were included. The median length of hospitalization was 14 days. Overall, 86 patients (7.6%; 95% CI, 6.1-9.2%) developed SAP and 47 patients (4.3%; 95% CI, 3.0-5.3%) developed GIB during hospitalization. After adjusting potential confounders, SAP was significantly associated with the development of GIB after ischemic stroke (OR = 5.13; 95% CI, 2.02-13.00; P < 0.001). The median time from stroke onset to diagnosis of SAP was shorter than that of GIB after ischemic stroke (4 days vs. 5 days; P = 0.039). CONCLUSIONS: SAP was associated with GIB after ischemic stroke, and the onset time of SAP was earlier than that of GIB. It is imperative to take precautions to prevent GIB in stroke patients with SAP.

The impact of physical therapy intervention of dysphagia on preventing pneumonia in acute stroke patients: A randomized controlled trial.

BACKGROUND AND OBJECTIVES: Dysphagia is a common complication following stroke. It corresponds to the development of pneumonia, which is always associated with bad prognosis, longer hospital stays and increased mortality. The aim of the study was to assess the impact of physical therapy intervention of dysphagia on preventing pneumonia in acute stroke patients. METHODS: A single-blind randomized controlled trial was carried out on 70 ischemic stroke patients with oropharyngeal dysphagia, age ranged from 49 to 65 years. They were randomly assigned to two groups (control and study) of equal number. Patients in the control group received oral care and nasogastric tube feeding, while patients in the study group received the same program in addition to the designed physical therapy program (exercises and neuromuscular electrical stimulation). The intervention program was applied for 40 min/session, 1 session/day, and 5 days/week for 4 weeks. Gugging swallowing screen (GUSS), and stroke associated pneumonia (SAP) control and prevention criteria were used to assess dysphagia and incidence of pneumonia at baseline, after two and 4 weeks of intervention for both groups. RESULTS: Before treatment, all patients were susceptible to pneumonia after two and 4 weeks of intervention; there were a significant increase in GUSS score in both groups with more improvement in favor of the study group (p < 0.05) and a statistically significant increase in incidence of SAP after 2 weeks of intervention only in the control group (p < 0.05). The results also showed a significant negative correlation between GUSS score and SAP (r = - 0.3662, p = 0.0018) IMPLICATIONS FOR PHYSIOTHERAPY PRACTICE: adding physical therapy (exercise therapy and neuromuscular electrical stimulation) to oral care and nasogastric tube feeding is effective in improving oropharyngeal dysphagia and decreasing the incidence of aspiration pneumonia in acute ischemic stroke patients.

Endogenous LXR signaling controls pulmonary surfactant homeostasis and prevents lung inflammation.

Lung type 2 pneumocytes (T2Ps) and alveolar macrophages (AMs) play crucial roles in the synthesis, recycling and catabolism of surfactant material, a lipid/protein fluid essential for respiratory function. The liver X receptors (LXR), LXRα and LXRß, are transcription factors important for lipid metabolism and inflammation. While LXR activation exerts anti-inflammatory actions in lung injury caused by lipopolysaccharide (LPS) and other inflammatory stimuli, the full extent of the endogenous LXR transcriptional activity in pulmonary homeostasis is incompletely understood. Here, using mice lacking LXRα and LXRß as experimental models, we describe how the loss of LXRs causes pulmonary lipidosis, pulmonary congestion, fibrosis and chronic inflammation due to defective de novo synthesis and recycling of surfactant material by T2Ps and defective phagocytosis and degradation of excess surfactant by AMs. LXR-deficient T2Ps display aberrant lamellar bodies and decreased expression of genes encoding for surfactant proteins and enzymes involved in cholesterol, fatty acids, and phospholipid metabolism. Moreover, LXR-deficient lungs accumulate foamy AMs with aberrant expression of cholesterol and phospholipid metabolism genes. Using a house dust mite aeroallergen-induced mouse model of asthma, we show that LXR-deficient mice exhibit a more pronounced airway reactivity to a methacholine challenge and greater pulmonary infiltration, indicating an altered physiology of LXR-deficient lungs. Moreover, pretreatment with LXR agonists ameliorated the airway reactivity in WT mice sensitized to house dust mite extracts, confirming that LXR plays an important role in lung physiology and suggesting that agonist pharmacology could be used to treat inflammatory lung diseases.

Loss-of-function/gain-of-function polymorphisms of the ATP sensitive P2X7R influence sepsis, septic shock, pneumonia, and survival outcomes.

Introduction: Extracellular ATP (eATP) released from damaged cells activates the P2X7 receptor (P2X7R) ion channel on the surface of surrounding cells, resulting in calcium influx, potassium efflux and inflammasome activation. Inherited changes in the P2X7R gene (P2RX7) influence eATP induced responses. Single nucleotide polymorphisms (SNPs) of P2RX7 influence both function and signaling of the receptor, that in addition to ion flux includes pathogen control and immunity. Methods: Subjects (n = 105) were admitted to the ICU at the University Hospital Ulm, Germany between June 2018 and August 2019. Of these, subjects with a diagnosis of sepsis (n = 75), were also diagnosed with septic shock (n = 24), and/or pneumonia (n = 42). Subjects with pneumonia (n = 43) included those without sepsis (n = 1), sepsis without shock (n = 29) and pneumonia with septic shock (n = 13). Out of the 75 sepsis/septic shock patients, 33 patients were not diagnosed with pneumonia. Controls (n = 30) were recruited to the study from trauma patients and surgical patients without sepsis, septic shock, or pneumonia. SNP frequencies were determined for 16 P2RX7 SNPs known to affect P2X7R function, and association studies were performed between frequencies of these SNPs in sepsis, septic shock, and pneumonia compared to controls. Results: The loss-of-function (LOF) SNP rs17525809 (T253C) was found more frequently in patients with septic shock, and non-septic trauma patients when compared to sepsis. The LOF SNP rs2230911 (C1096G) was found to be more frequent in patients with sepsis and septic shock than in non-septic trauma patients. The frequencies of these SNPs were even higher in sepsis and septic patients with pneumonia. The current study also confirmed a previous study by our group that showed a five SNP combination that included the GOF SNPs rs208294 (C489T) and rs2230912 (Q460R) that was designated #21211 was associated with increased odds of survival in severe sepsis. Discussion: The results found an association between expression of LOF P2RX7 SNPs and presentation to the ICU with sepsis, and septic shock compared to control ICU patients. Furthermore, frequencies of LOF SNPs were found to be higher in sepsis patients with pneumonia compared to those without pneumonia. In addition, a five SNP GOF combination was associated with increased odds of survival in severe sepsis. These results suggest that P2RX7 is required to control infection in pneumonia and that inheritance of LOF variants increases the risk of sepsis when associated with pneumonia. This study confirms that P2RX7 genotyping in pneumonia may identify patients at risk of developing sepsis. The study also identifies P2X7R as a target in sepsis associated with an excessive immune response in subjects with GOF SNP combinations.

Analysis of com plication s af te r out-of-ho sp i ta l cardiac a rr est of tar ge t temperat ure management.

OBJECTIVE: To analyse the preva lence of complications related to out-of-hospital cardiac arrest patients achieving target temperature management within 360 minutes compared to those taking more than 360 minutes. METHODS: The retrospective study was conducted at a medical centre in Taiwan, and comprised data from Januar y 1, 2014, to December 31, 2020. Data was retrieved using the International Classification of Diseases version 10 codes I46.2, I46.8 and I46.9 related to adult patients of either gender presenting to the Emergenc y Medicine department with out-of-hospital cardiac arrest. Data included gender, age, medical histor y, body mass index, acute physiology and chronic health evaluation II score, blood glucose levels, electrocardiogram results, and complications occurring within the target temperature management timeframe. Data was divided into group A having patients who achieved target temperature management within 360 minutes, and group B having patients with delayed TTM of more than 360 minutes. Data was analysed using SPSS 22. RESULTS: Of the 127 patients, 76(59%) were males, 51(41%) were females,, 47(37%) were aged >75 years, and 13(10.3%) were aged <50 years. Of the total, 65(51.2%) patients were in group A, and 62(48.8%) were in group B. Pneumonia, urinary tract infection, septic shock and gastrointestinal bleeding had lower incidence rates in group A than group B (p<0.05). The odds of death were 2.879 times high er in group B patients than group A (95% confidence interval: 1.908-8.916). CONCLUSIONS: Hypothermia tre atment should be sta rted as soon as pos sible to achieve target temp erature management within 360 minutes to reduce the risk of complications and mortality.

Comparison of NEWS2 and PSI as mortality predictors in patients with community acquired pneumonia.

In the West, National Early Warning Score 2 (NEWS2) is commonly applied to predict the severity of illness using only bedside variables unlike the extensive Pneumonia Severity Index (PSI). The objective of this study was to compare these scores as mortality predictors in patients admitted with community acquired pneumonia (CAP). This cross-sectional study was conducted in Jinnah Postgraduate Medical Centre, Karachi, Pakistan, for six months in 2020 on 116 patients presenting with CAP. Cases of aspiration pneumonia, hospital acquired pneumonia, pulmonary tuberculosis, pulmonary embolism, and pulmonary oedema were excluded. In-hospital mortality was taken as the outcome of this study. The mean age of the participants was 46.9±20.5 years. The in-hospital mortalities were 45(38.8%). NEWS2 was 97.8% sensitive but only 15.5% specific in predicting the outcome, whereas PSI was less sensitive (68.9%) but more specific (50.7%), which showed that in comparison with PSI, NEWS2 is a more sensitive mortality predicting score among hospitalised CAP patients.

Differences in the risk of immune-related pneumonitis between PD-1 and PD-L1 inhibitors: a meta-analysis according to the new mirror-principle and PRISMA guidelines.

PURPOSE: To compare the risk of immune-associated pneumonitis between PD-1 and PD-L1 inhibitors, the meta-analysis was designed. METHOD: The difference in risk of immune-associated pneumonitis between PD-1 and PD-L1 inhibitors was assessed by two different meta-analysis methods, the Mirror-pairing and the PRISMA guidelines. RESULTS: A total of eighty-eight reports were used for meta-analysis, while thirty-two studies were used for the Mirror-pairing. Both PD-1 and PD-L1 inhibitors (used alone or combined with chemotherapy) increased the risk of developing immune-related pneumonitis (P < 0.00001; P < 0.00001). Based on indirect analyses results (subgroup analyses), the risk of PD-L1-induced pneumonitis was weaker than that of PD-1 inhibitors when the control group was chemotherapy (OR = 3.33 vs. 5.43) or placebo (OR = 2.53 vs. 3.19), while no obvious significant differences were found (P = 0.17; P = 0.53). For the Mirror-pairing-based meta-analysis, the risk of PD-1-induced pneumonitis was significantly higher than that of PD-L1 inhibitors (OR = 1.46, 95%CI [1.08, 1.98], I2 = 0%, Z = 2.47 (P = 0.01)). However, this difference was not significant, when they were combined with chemotherapy (OR = 1.05, 95%CI [0.68, 1.60], I2 = 38%, Z = 0.21 (P = 0.84)). CONCLUSION: Both PD-1 and PD-L1 inhibitors increased the risk of immune-related pneumonitis, while the risk of PD-1-induced pneumonitis was significantly higher than that of PD-L1 inhibitors.

Lymphocyte-Directed Immunomodulation Remits Thymoma-Associated Autoimmune Pneumonitis.

BACKGROUND: Thymoma presents with several autoimmune manifestations and is associated with secondary autoimmune regulator (AIRE) deficiency. Pneumonitis has recently been described as an autoimmune manifestation associated with thymoma presenting with similar clinical, radiographic, histological, and autoantibody features as seen in patients with inherited AIRE deficiency who suffer from Autoimmune PolyEndocrinopathy-Candidiasis-Ectodermal Dystrophy (APECED) syndrome. OBJECTIVES: To treat two patients with biopsy-proven thymoma-associated pneumonitis with lymphocyte-directed immunomodulation. METHODS: Two patients with thymoma were enrolled on IRB-approved protocols at the NIH Clinical Center. We performed history and physical examination; laboratory, radiographic, histologic and pulmonary function evaluations; and measurement of the lung-directed autoantibodies KCNRG and BPIFB1 prior to and at 1- and 6-months following initiation of lymphocyte-directed immunomodulation with azathioprine with or without rituximab. RESULTS: Combination T- and B-lymphocyte-directed immunomodulation resulted in improvement of clinical, functional, and radiographic parameters at 6-month follow-up evaluations in both patients with sustained remission up to 12-36 months following treatment initiation. CONCLUSION: Lymphocyte-directed immunomodulation remitted autoimmune pneumonitis in two patients with thymoma.

Impact of Toll-like receptor 2 (rs5743708) gene polymorphism in pediatric pneumonia: risk and severity.

Pediatric pneumonia is a common respiratory infection that affects children and is thought to be a major source of mortality and morbidity worldwide, particularly in low- and middle-income nations. Toll-like receptor2 (TLR2) is an important receptor involved in the recognition of bacterial pathogens and the activation of the immune response. Genetic variability in TLR2 may partially explain individual differences in susceptibility to infections. The purpose of this study was to investigate the possible contribution of the TLR2 (rs5743708) variant to the risk and severity of pediatric pneumonia infection. The study included 100 pediatric patients diagnosed with pneumonia and 100 normal controls who were age and gender matched. Real-time polymerase chain reaction (PCR) was used to genotype participants for the TLR2 (rs5743708) variant. The analysis revealed that children with the TLR2 (rs5743708) (G/A) genotype showed a 2.52-fold greater risk of having pneumonia (OR: 2.52; 95% CI: 1.32-4.79; p = 0.005) in comparison with patients who have wild homozygous genotypes. Furthermore, we observed that the TLR2 (rs5743708) (A) allele is connected to a greater risk of pneumonia infection in children (OR: 1.612; 95% CI: 1.07-2.43; p = 0.023) but did not significantly influence infection severity. In conclusion, children with the TLR2 (rs5743708) mutant (G/A) genotype and (A) allele had a significantly higher risk of having pneumonia, but they were not at high risk for the severity of the infection.

COVID-19 and Pneumonia detection and web deployment from CT scan and X-ray images using deep learning.

During the COVID-19 pandemic, pneumonia was the leading cause of respiratory failure and death. In addition to SARS-COV-2, it can be caused by several other bacterial and viral agents. Even today, variants of SARS-COV-2 are endemic and COVID-19 cases are common in many places. The symptoms of COVID-19 are highly diverse and robust, ranging from invisible to severe respiratory failure. Current detection methods for the disease are time-consuming and expensive with low accuracy and precision. To address such situations, we have designed a framework for COVID-19 and Pneumonia detection using multiple deep learning algorithms further accompanied by a deployment scheme. In this study, we have utilized four prominent deep learning models, which are VGG-19, ResNet-50, Inception V3 and Xception, on two separate datasets of CT scan and X-ray images (COVID/Non-COVID) to identify the best models for the detection of COVID-19. We achieved accuracies ranging from 86% to 99% depending on the model and dataset. To further validate our findings, we have applied the four distinct models on two more supplementary datasets of X-ray images of bacterial pneumonia and viral pneumonia. Additionally, we have implemented a flask app to visualize the outcome of our framework to show the identified COVID and Non-COVID images. The findings of this study will be helpful to develop an AI-driven automated tool for the cost effective and faster detection and better management of COVID-19 patients.

Clinical application of targeted next-generation sequencing in severe pneumonia: a retrospective review.

BACKGROUND: The precise identification of the underlying causes of infectious diseases, such as severe pneumonia, is essential, and the development of next-generation sequencing (NGS) has enhanced the effectiveness of pathogen detection. However, there is limited information on the systematic assessment of the clinical use of targeted next-generation sequencing (tNGS) in cases of severe pneumonia. METHODS: A retrospective analysis was conducted on 130 patients with severe pneumonia treated in the ICU from June 2022 to June 2023. The consistency of the results of tNGS, metagenomics next-generation sequencing (mNGS), and culture with the clinical diagnosis was evaluated. Additionally, the results for pathogens detected by tNGS were compared with those of culture, mNGS, and quantitative reverse transcription PCR (RT-qPCR). To evaluate the efficacy of monitoring severe pneumonia, five patients with complicated infections were selected for tNGS microbiological surveillance. The tNGS and culture drug sensitisation results were then compared. RESULTS: The tNGS results for the analysis of the 130 patients showed a concordance rate of over 70% with clinical diagnostic results. The detection of pathogenic microorganisms using tNGS was in agreement with the results of culture, mNGS, and RT-qPCR. Furthermore, the tNGS results for pathogens in the five patients monitored for complicated infections of severe pneumonia were consistent with the culture and imaging test results during treatment. The tNGS drug resistance results were in line with the drug sensitivity results in approximately 65% of the cases. CONCLUSIONS: The application of tNGS highlights its promise and significance in assessing the effectiveness of clinical interventions and providing guidance for anti-infection therapies for severe pneumonia.

[Prediction of risk of in-hospital death in patients with chronic heart failure complicated by lung infections using interpretable machine learning].

OBJECTIVE: To predict the risk of in-hospital death in patients with chronic heart failure (CHF) complicated by lung infections using interpretable machine learning. METHODS: The clinical data of 1415 patients diagnosed with CHF complicated by lung infections were obtained from the MIMIC-IV database. According to the pathogen type, the patients were categorized into bacterial pneumonia and non-bacterial pneumonia groups, and their risks of in-hospital death were compared using Kaplan-Meier survival curves. Univariate analysis and LASSO regression were used to select the features for constructing LR, AdaBoost, XGBoost, and LightGBM models, and their performance was compared in terms of accuracy, precision, F1 value, and AUC. External validation of the models was performed using the data from eICU-CRD database. SHAP algorithm was applied for interpretive analysis of XGBoost model. RESULTS: Among the 4 constructed models, the XGBoost model showed the highest accuracy and F1 value for predicting the risk of in-hospital death in CHF patients with lung infections in the training set. In the external test set, the XGBoost model had an AUC of 0.691 (95% CI: 0.654-0.720) in bacterial pneumonia group and an AUC of 0.725 (95% CI: 0.577-0.782) in non-bacterial pneumonia group, and showed better predictive ability and stability than the other models. CONCLUSION: The overall performance of the XGBoost model is superior to the other 3 models for predicting the risk of in-hospital death in CHF patients with lung infections. The SHAP algorithm provides a clear interpretation of the model to facilitate decision-making in clinical settings.

Two-year survival after scheduled extubation in patients with pneumonia or ARDS: a prospective observational study.

PURPOSE: To report two-year survival after scheduled extubation in patients with pneumonia or acute respiratory distress syndrome (ARDS). METHODS: This was a prospective observational study performed in a respiratory ICU of a teaching hospital. Pneumonia or ARDS patients who successfully completed a spontaneous breathing trial were enrolled. Data were collected before extubation. Patients were followed up to two years by phone every 3 months. RESULTS: A total of 230 patients were enrolled in final analysis. One-, 3-, 6-, 12-, and 24-month survival was 77.4%, 63.8%, 61.3%, 57.8%, and 47.8%, respectively. Cox regression shows that Charlson comorbidity index (hazard ratio: 1.20, 95% confidence interval: 1.10-1.32), APACHE II score before extubation (1.11, 1.05-1.17), cough peak flow before extubation (0.993, 0.986-0.999), and extubation failure (3.96, 2.51-6.24) were associated with two-year mortality. To predict death within two years, the area under the curve of receiver operating characteristic was 0.79 tested by Charlson comorbidity index, 0.75 tested by APACHE II score, and 0.75 tested by cough peak flow. Two-year survival was 31% and 77% in patients with Charlson comorbidity index ≥ 1 and < 1, 28% and 62% in patients with APACHE II score ≥ 12 and < 12, and 64% and 17% in patients with cough peak flow > 58 and ≤ 58 L/min, respectively. CONCLUSIONS: Comorbidity, disease severity, weak cough and extubation failure were associated with increased two-year mortality in pneumonia or ARDS patients who experienced scheduled extubation. It provides objective information to caregivers to improve decision-making process during hospitalization and post discharge.

Performance of risk scores in predicting mortality at 3, 6, and 12 months in patients diagnosed with community-acquired pneumonia.

BACKGROUND: Risk scores (RS) evaluate the likelihood of short-term mortality in patients diagnosed with community-acquired pneumonia (CAP). However, there is a scarcity of evidence to determine the risk of long-term mortality. This article aims to compare the effectiveness of 16 scores in predicting mortality at three, six, and twelve months in adult patients with CAP. METHODS: A retrospective cohort study on individuals diagnosed with CAP was conducted across two hospitals in Colombia. Receiver Operating Characteristic (ROC) curves were constructed at 3, 6, and 12 months to assess the predictive ability of death for the following scoring systems: CURB-65, CRB-65, SCAP, CORB, ADROP, NEWS, Pneumonia Shock, REA-ICU, PSI, SMART-COP, SMRT-CO, SOAR, qSOFA, SIRS, CAPSI, and Charlson Comorbidity Index (CCI). RESULTS: A total of 3688 patients were included in the final analysis. Mortality at 3, 6, and 12 months was 5.2%, 8.3%, and 16.3% respectively. At 3 months, PSI, CCI, and CRB-65 scores showed ROC curves of 0.74 (95% CI: 0.71-0.77), 0.71 (95% CI: 0.67-0.74), and 0.70 (95% CI: 0.66-0.74). At 6 months, PSI and CCI scores showed performances of 0.74 (95% CI: 0.72-0.77) and 0.72 (95% CI: 0.69-0.74), respectively. Finally at 12 months, all evaluated scores showed poor discriminatory capacity, including PSI, which decreased from acceptable to poor with an ROC curve of 0.64 (95% CI: 0.61-0.66). CONCLUSION: When predicting mortality in patients with CAP, at 3 months, PSI, CCI, and CRB-65 showed acceptable predictive performances. At 6 months, only PSI and CCI maintained acceptable levels of accuracy. For the 12-month period, all evaluated scores exhibited very limited discriminatory ability, ranging from poor to almost negligible.

An assessment of the value of deep neural networks in genetic risk prediction for surgically relevant outcomes.

INTRODUCTION: Postoperative complications affect up to 15% of surgical patients constituting a major part of the overall disease burden in a modern healthcare system. While several surgical risk calculators have been developed, none have so far been shown to decrease the associated mortality and morbidity. Combining deep neural networks and genomics with the already established clinical predictors may hold promise for improvement. METHODS: The UK Biobank was utilized to build linear and deep learning models for the prediction of surgery relevant outcomes. An initial GWAS for the relevant outcomes was initially conducted to select the Single Nucleotide Polymorphisms for inclusion in the models. Model performance was assessed with Receiver Operator Characteristics of the Area Under the Curve and optimum precision and recall. Feature importance was assessed with SHapley Additive exPlanations. RESULTS: Models were generated for atrial fibrillation, venous thromboembolism and pneumonia as genetics only, clinical features only and a combined model. For venous thromboembolism, the ROC-AUCs were 60.1% [59.6%-60.4%], 63.4% [63.2%-63.4%] and 66.6% [66.2%-66.9%] for the linear models and 51.5% [49.4%-53.4%], 63.2% [61.2%-65.0%] and 62.6% [60.7%-64.5%] for the deep learning SNP, clinical and combined models, respectively. For atrial fibrillation, the ROC-AUCs were 60.3% [60.0%-60.4%], 78.7% [78.7%-78.7%] and 80.0% [79.9%-80.0%] for the linear models and 59.4% [58.2%-60.9%], 78.8% [77.8%-79.8%] and 79.8% [78.8%-80.9%] for the deep learning SNP, clinical and combined models, respectively. For pneumonia, the ROC-AUCs were 50.1% [49.6%-50.6%], 69.2% [69.1%-69.2%] and 68.4% [68.0%-68.5%] for the linear models and 51.0% [49.7%-52.4%], 69.7% [.5%-70.8%] and 69.7% [68.6%-70.8%] for the deep learning SNP, clinical and combined models, respectively. CONCLUSION: In this report we presented linear and deep learning predictive models for surgery relevant outcomes. Overall, predictability was similar between linear and deep learning models and inclusion of genetics seemed to improve accuracy.

MMP-3 mediates copper oxide nanoparticle-induced pulmonary inflammation and fibrosis.

BACKGROUND: The increasing production and usage of copper oxide nanoparticles (Nano-CuO) raise human health concerns. Previous studies have demonstrated that exposure to Nano-CuO could induce lung inflammation, injury, and fibrosis. However, the potential underlying mechanisms are still unclear. Here, we proposed that matrix metalloproteinase-3 (MMP-3) might play an important role in Nano-CuO-induced lung inflammation, injury, and fibrosis. RESULTS: Exposure of mice to Nano-CuO caused acute lung inflammation and injury in a dose-dependent manner, which was reflected by increased total cell number, neutrophil count, macrophage count, lactate dehydrogenase (LDH) activity, and CXCL1/KC level in bronchoalveolar lavage fluid (BALF) obtained on day 3 post-exposure. The time-response study showed that Nano-CuO-induced acute lung inflammation and injury appeared as early as day 1 after exposure, peaked on day 3, and ameliorated over time. However, even on day 42 post-exposure, the LDH activity and macrophage count were still higher than those in the control group, suggesting that Nano-CuO caused chronic lung inflammation. The Nano-CuO-induced pulmonary inflammation was further confirmed by H&E staining of lung sections. Trichrome staining showed that Nano-CuO exposure caused pulmonary fibrosis from day 14 to day 42 post-exposure with an increasing tendency over time. Increased hydroxyproline content and expression levels of fibrosis-associated proteins in mouse lungs were also observed. In addition, Nano-CuO exposure induced MMP-3 overexpression and increased MMP-3 secretion in mouse lungs. Knocking down MMP-3 in mouse lungs significantly attenuated Nano-CuO-induced acute and chronic lung inflammation and fibrosis. Moreover, Nano-CuO exposure caused sustained production of cleaved osteopontin (OPN) in mouse lungs, which was also significantly decreased by knocking down MMP-3. CONCLUSIONS: Our results demonstrated that short-term Nano-CuO exposure caused acute lung inflammation and injury, while long-term exposure induced chronic pulmonary inflammation and fibrosis. Knocking down MMP-3 significantly ameliorated Nano-CuO-induced pulmonary inflammation, injury, and fibrosis, and also attenuated Nano-CuO-induced cleaved OPN level. Our study suggests that MMP-3 may play important roles in Nano-CuO-induced pulmonary inflammation and fibrosis via cleavage of OPN and may provide a further understanding of the mechanisms underlying Nano-CuO-induced pulmonary toxicity.

Alveolar fibroblast lineage orchestrates lung inflammation and fibrosis.

Fibroblasts are present throughout the body and function to maintain tissue homeostasis. Recent studies have identified diverse fibroblast subsets in healthy and injured tissues1,2, but the origins and functional roles of injury-induced fibroblast lineages remain unclear. Here we show that lung-specialized alveolar fibroblasts take on multiple molecular states with distinct roles in facilitating responses to fibrotic lung injury. We generate a genetic tool that uniquely targets alveolar fibroblasts to demonstrate their role in providing niches for alveolar stem cells in homeostasis and show that loss of this niche leads to exaggerated responses to acute lung injury. Lineage tracing identifies alveolar fibroblasts as the dominant origin for multiple emergent fibroblast subsets sequentially driven by inflammatory and pro-fibrotic signals after injury. We identify similar, but not completely identical, fibroblast lineages in human pulmonary fibrosis. TGFß negatively regulates an inflammatory fibroblast subset that emerges early after injury and stimulates the differentiation into fibrotic fibroblasts to elicit intra-alveolar fibrosis. Blocking the induction of fibrotic fibroblasts in the alveolar fibroblast lineage abrogates fibrosis but exacerbates lung inflammation. These results demonstrate the multifaceted roles of the alveolar fibroblast lineage in maintaining normal alveolar homeostasis and orchestrating sequential responses to lung injury.

Respiratory syncytial virus-associated pneumonia in primary care in Malawi.

OBJECTIVE: To identify the prevalence of respiratory syncytial virus (RSV) in a cohort of children under 5 years of age with World Health Organization (WHO)-defined pneumonia and the factors associated with developing severe RSV-associated community-acquired pneumonia (CAP) in primary care in a single centre in Northern Malawi. METHODS: The BIOmarkers TO diagnose PnEumonia (BIOTOPE) study was a prospective cohort study conducted from March to June 2016 that took place in a primary care centre in Northern Malawi. Data from this study was used to identify the characteristics of children under 5 years of age who presented with RSV and WHO-defined CAP. Means, standard deviations, medians and ranges were calculated for continuous variables. A univariate logistic regression was performed to examine the potential predictor variables. RESULTS: Four hundred and ninety-four infants presented with CAP and were eligible for inclusion in the study; RSV infection was detected in 205 (41.6%) of the infants. Eight factors were associated with increased risk for RSV CAP in the univariate model: age, born at term, presenting for care in June, crowded living environment, not being exclusively breastfed, not having received zinc or vitamin A supplementation in the last six months. Infants with RSV were more likely to have an oxygen saturation ≤92% compared to infants with other causes of pneumonia and more likely to have severe pneumonia as defined by the WHO. CONCLUSION: This study supports that RSV-associated CAP is linked to modifiable and non-modifiable risk factors; further research is indicated to determine which interventions would be most impactful. Developing and implementing an infant or maternal vaccine could be a cost-effective way to prevent RSV-associated CAP and mortality in developing nations. More research is needed to understand seasonal patterns of CAP and research over extended periods can offer valuable insights on host, environmental and pathogen-specific factors that contribute to RSV-associated CAP.

Time to recovery and its predictors among under-five children admitted with severe pneumonia in East Wallaga Zone public hospitals, western Ethiopia, 2023; a retrospective cohort study.

BACKGROUND: Globally, pneumonia is one of the leading causes of morbidity and mortality as well as hospitalization burden for under-five children. Despite significant initiatives implemented to reduce morbidity and mortality from pneumonia in under-five children, little is known regarding the time to recovery and its predictors among under-five children admitted with severe pneumonia in Ethiopia. Hence, this study intended to estimate the median time to recovery and its predictors among under-five children admitted with severe pneumonia in East Wallaga zone public hospitals, western Ethiopia; 2023. METHODS: An institution-based retrospective cohort study was conducted among 383 under-five children who were admitted with severe pneumonia in East Wallaga zone public hospitals from January 2017 to December 2022. A systematic sampling method was used to select eligible medical records. EpiData Version 4.6 was used to enter the data and analyzed using STATA Version 17.0. Cox-proportional hazard assumption test and model fitness were checked. Variables with P-value ˂ 0.25 at bivariable Cox regression analysis were selected for the multivariable Cox proportional model. A multivariable Cox regression model with 95% CI and Adjusted Hazard Ratio (AHR) was used to identify a significant predictor of time to recovery from severe pneumonia at a P-value < 0.05. RESULTS: At the end of the follow-up, 356 observations were developed an event (recovered) with the median time to recovery of 4 days with IQR of 3-5 days. The overall incidence rate of recovery was 22.26 per 100 (95% CI: 20.07-24.70) person-days observations. Being rural residency (AHR: 0.75, 95% CI: 0.60-0.93), late presenters for seeking care (AHR = 0.70, 95% CI: 0.53-0.93), presence of danger sign at admission (AHR = 1.46, 95% CI: 1.15-1.83), and presence of comorbidity (AHR = 1.63, 95% CI, 1.31-2.04) were found to have a statistically significant association with prolonged recovery time. CONCLUSION: The median time to recovery from severe pneumonia was long, and factors such as Residence, co-morbidity, presence of danger signs, and duration prior to seeking care were statistically significant predictors of recovery time from severe pneumonia. Hence, due attention has to be given to increasing the community's health-seeking behavior to visit health facility early and especial attention should be given for children with danger signs and comorbidity.