Alveolar Fluid Research Articles

Impact of the elderly lung mucosa on Mycobacterium tuberculosis transcriptional adaptation during infection of alveolar epithelial cells.

Tuberculosis is one of the leading causes of death due to a single infectious agent. Upon infection, Mycobacterium tuberculosis (M.tb) is deposited in the alveoli and encounters the lung mucosa or alveolar lining fluid (ALF). We previously showed that, as we age, ALF presents a higher degree of oxidation and inflammatory mediators, which favors M.tb replication in human macrophages and alveolar epithelial cells (ATs). Here, we define the transcriptional profile of M.tb when exposed to healthy ALF from adult (A-ALF) or elderly (E-ALF) humans before and during infection of ATs. Prior to infection, M.tb exposure to E-ALF upregulated genes essential for bacterial host adaptation directly involved in M.tb pathogenesis. During infection of ATs, E-ALF exposed M.tb further upregulated genes involved in its ability to escape into the AT cytosol bypassing critical host defense mechanisms, as well as genes associated with defense against oxidative stress. These findings demonstrate how alterations in human ALF during the aging process can impact the metabolic status of M.tb, potentially enabling a greater adaptation and survival within host cells. Importantly, we present the first transcriptomic analysis on the impact of the elderly lung mucosa on M.tb pathogenesis during intracellular replication in ATs.IMPORTANCETuberculosis is one of the leading causes of death due to a single infectious agent. Upon infection, Mycobacterium tuberculosis (M.tb) is deposited in the alveoli and comes in contact with the alveolar lining fluid (ALF). We previously showed that elderly ALF favors M.tb replication in human macrophages and alveolar epithelial cells (ATs). Here we define the transcriptional profile of when exposed to healthy ALF from adult (A-ALF) or elderly (E-ALF) humans before and during infection of ATs. Prior to infection, exposure to E-ALF upregulates genes essential for bacterial host adaptation and pathogenesis. During infection of ATs, E-ALF further upregulates M.tb genes involved in its ability to escape into the AT cytosol, as well as genes for defense against oxidative stress. These findings demonstrate how alterations in human ALF during the aging process can impact the metabolic status of M.tb, potentially enabling a greater adaptation and survival within host cells.

Oxidative stress in the alveolar lavage fluid of children with Mycoplasma pneumoniae pneumonia.

To investigate the correlation between oxidative stress in the bronchoalveolar lavage fluid (BALF) of children with Mycoplasma pneumoniae pneumonia (MPP) and the clinical characteristics of severe MPP (SMPP) and refractory MPP (RMPP). Clinical and BALF-related data were collected from 83 patients with MPP, of which 29 had SMPP and 54 had general MPP (GMPP); 37 patients were in the RMPP group and 46 in the non-RMPP group. The levels of malondialdehyde (MDA) and advanced oxidation protein products (AOPP) as well as the activity levels of superoxide dismutase (SOD) and glutathione peroxidase (GSH-PX) in BALF were detected. Logistic regression analyses were performed on MDA, AOPP, SOD, GSH-PX, gender, heat peak, neutrophil percentage, C-reactive protein, lactate dehydrogenase, d-dimer, lung consolidation, sputum embolus, and pleural effusion. The levels of MDA and AOPP in the BALF of the MPP group were significantly higher than those in the control group (p < .05), whereas SOD and GSH-PX levels were lower than those in the control group (p < .05). The BALF AOPP levels in the RMPP group were higher than those in the non-RMPP group, and the SOD and GSH-PX levels in the BALF were lower than those in the non-RMPP group; the difference was statistically significant (p < .05). The levels of MDA and AOPP in the BALF of children in the SMPP group were higher than those in the GMPP group, and the levels of SOD and GSH-PX were lower than those in the GMPP group, with statistically significant differences (p < .05). The C-index of the logistic regression model was 0.960 (95% confidence interval 0.958-0.963), which indicates that the model has good predictive ability. Advanced oxidation protein products may be a marker for predicting the conditions of SMPP and RMPP, and the prediction model can assess the risk of progression in children to RMPP, which is conducive to clinical diagnosis and treatment.

Non-inferiority trial in veal calves on the efficacy of oxytetracycline and florfenicol treatment for pneumonia guided by quick thoracic ultrasound

Purchase dependent calf rearing systems, such as the white veal industry, systematically rely on antimicrobial mass medication (metaphylaxis) to counter respiratory tract infections. Despite mounting criticism, the industry fears that without metaphylaxis, mortality would drastically increase. This randomized clinical trial aimed to compare the efficacy of a quick thoracic ultrasonography (qTUS) individualized treatment length between oxytetracycline (OTC) and florfenicol (FF). Regression of maximum consolidation depth < 1cm was used as a criterion for cure and to stop antimicrobial treatment. Additionally, the study assessed the associations of consolidation depth at treatment initiation with cure and treatment duration. The trial involved 320 veal calves, randomly assigned into one of 2 groups: one receiving OTC (n = 160) and the other FF (n = 160) on d 1 (2-d metaphylaxis). Clinical scoring and qTUS were done on d 1 and every 48 h for a 10-d period. After d 1, only calves with consolidations ≥ 1cm were given further treatment. On each time point, maximum consolidation depth was used to categorize calves into 4 qTUS categories: healthy (no consolidation), mild pneumonia (consolidation < 1cm), moderate pneumonia (consolidation 1-3cm) and severe pneumonia (consolidation ≥ 3cm). Cure, treatment duration and the number of antimicrobial dosages (NAD) were compared between treatment groups. In addition, pathogen identification and antimicrobial susceptibility testing was performed on isolates from non-endoscopic broncho alveolar lavage fluid. On d 1, 30.0% (96/320) of the calves had consolidation ≥ 1cm, which increased to 50.9% (162/318) by d 9. After single metaphylactic treatment, cure was 20.9% (9/43) and 20.9% (9/43) in the OTC and FF group, respectively. Calves with severe pneumonia had lower odds to be cured after first treatment than calves with moderate pneumonia (Odds ratio (OR) = 0.17; 95% Confidence interval (CI): 0.04 - 0.63). By d 9, final cure of the initial cases was 27.9% in both the OTC- and FF-group. both groups, cure was similar at all observation points (P > 0.05). Overall, final cure of all calves with either moderate or severe pneumonia during the trial was 41.2% (52/102) and 19.0% (12/63), respectively (P = 0.004). Median treatment duration was 4 d (Interquartile range (IQR) = 2-6; Minimum (Min) = 2; Maximum (Max) = 8) and was similar in both treatment groups (P = 0.59). Treatment duration for calves with moderate pneumonia (Med = 6; IQR = 4-6; Min = 2; Max = 8) was lower than the median treatment duration of calves with severe pneumonia (Med = 8; IQR = 4-8; Min = 2; Max = 8) (P = 0.004). When compared with calves with mild pneumonia on d 1, calves with moderate (P = 0.01) and severe pneumonia (P < 0.001) had significantly longer treatment durations. In this study, cure was low and not different between both antimicrobials. Categorizing calves based on consolidation depth appears useful as both cure and treatment duration were different for the mild, moderate and severe group.

Occludin Is Essential to Maintain Normal Alveolar Barrier Integrity and Its Protective Role During ARDS Progression.

Acute respiratory distress syndrome (ARDS) is a severe lung condition without targeted therapy that is characterized by the disruption of epithelial and endothelial barriers. The role of the tight junction protein occludin in the pathogenesis of this disease is unknown, although it has previously been deemed redundant in some tissues. The aim of the present study is to determine whether occludin is required for lung function by controlling alveolar barrier integrity in mouse models. Immunofluorescence staining of lungs from ARDS patients revealed a significant decrease in occludin expression compared to controls. Gene delivery of shRNA against occludin in the mouse lung reduced occludin levels and induced lung injury, as assessed by wet-to-dry-ratio, histology, and cellularity and protein content of bronchial alveolar lavage fluid. Conversely, gene delivery of an occludin-expressing plasmid increased occludin expression and dampened endotoxin-induced lung injury. In primary rat alveolar epithelial cells, occludin levels were positively correlated with barrier integrity, as well as membrane localization of claudin-18, another tight junction protein. Collectively, our data demonstrate that occludin plays a significant role in alveolar barrier function and that targeting occludin may provide a new therapeutic approach for ARDS.

Severe co-infection caused by difficult-to-diagnose hypermucoviscous Klebsiella pneumoniae K1-ST82 in a patient with COVID-19: a case report

BackgroundCo-infection with Klebsiella pneumoniae presents a significant concern in hospitalized patients with coronavirus disease (COVID-19), increasing the risk of severe disease progression. Hypervirulent (hv) and hypermucoviscous (hm) K. pneumoniae (Kp) has gained prominence in Asia due to its capacity to cause invasive community-acquired infections. However, recognition of hvKp/hmKp co-infections in the context of COVID-19 remains limited. We report a severe case of rapidly progressing co-infection with hmKp exhibiting “difficult-to-diagnose” phenotypes in a hospitalized patient with COVID-19.Case presentationA 61-year-old woman with COVID-19 initially exhibited mild symptoms resembling the common cold. However, her condition rapidly deteriorated over 7 days, leading to hospital admission with the development of dyspnea. The patient required supplemental oxygen, antibiotic treatment, and mechanical ventilation. Gram-negative bacteria with atypical phenotypes were isolated from alveolar lavage fluid and blood cultures. Both strains formed small, glossy, non-lactose-fermenting colonies on clinically relevant media and were susceptible to ampicillin. Conventional biochemical tests failed to identify the Enterobacteriales strains owing to the urease-negative phenotype. Consequently, the identification of K. pneumoniae was difficult until matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) analysis was performed. A positive string test indicated mucoviscosity, but with variability in the material used for stretching colonies. Whole-genome sequencing performed on the MiSeq and GridION platforms revealed the blood-derived strain JARB-RN-0063 as belonging to serotype K1 and sequence type (ST) 82. The hvKp-associated genes rmpA and iroCD were located on a 5.0-Mb chromosome, and iucABCD-iutA was identified on a 217.9-kb IncFIB(K)/IncR-type plasmid. Therefore, JARB-RN-0063 was genetically classified as hvKp with a Kleborate virulence score of 3. The intrinsic penicillinase gene blaSHV was defective owing to an IS1F element insertion, resulting in the strain being atypically susceptible to ampicillin.ConclusionsThis is the first case of severe COVID-19-associated co-infection with a difficult-to-diagnose K. penummoniae strain. Notably, co-infection by the hmKp K1-ST82 clone exhibited atypical phenotypes, including stunted growth, non-lactose fermentation, urease-negative reaction, ampicillin susceptibility, and abnormal mucoviscosity, posing diagnostic challenges for clinical laboratories and impedes the identification of hvKp/hmKp. Delayed identification may worsen patient outcomes, highlighting the need for increased clinical awareness of such difficult-to-diagnose clones to prevent deterioration.

Fatal invasive Aspergillus infection in an elderly patient with hepatitis E: A case report and literature review.

Elderly patients with acute liver failure are highly susceptible to severe complications, such as invasive fungal infections, due to weakened immune systems and altered gut microbiota. A thorough understanding of liver failure and opportunistic infections is crucial for effective management. An 84-year-old male with acute liver failure from hepatitis E experienced worsening jaundice despite standard treatments. He also developed respiratory symptoms, including blood-streaked sputum, raising concerns about a potential fungal infection. The patient was diagnosed with acute liver failure secondary to hepatitis E and an invasive fungal infection caused by Aspergillus fumigatus. Initial treatments included artificial liver plasma exchange and antifungal prophylaxis. Further diagnostics, including bronchoscopy and next-generation sequencing of alveolar lavage fluid, confirmed the Aspergillus infection. Elderly liver failure patients are particularly prone to opportunistic infections, underscoring the need for vigilant monitoring and early intervention. Despite aggressive treatments, including antifungal therapy and artificial liver support, prognosis remains poor, highlighting the importance of prompt diagnosis and comprehensive management to enhance patient outcomes.

Mesenchymal Stem Cell Therapy Mitigates Acute and Chronic Lung Damages of Sulfur Mustard Analog Exposure

Sulfur mustard (SM) is an established chemical weapon that can result in severe damage to parts of the body. Currently, there are no effective treatments available for SM-caused damage. We aimed to investigate the therapeutic potential of adipose-derived mesenchymal stromal cells (AD-MSCs) and conditioned medium (CM-MSCs) in acute and chronic pulmonary mouse models caused by 2-chloroethyl ethyl sulfide (CEES), an SM analog. The mice were divided into 4 experimental groups:(1) CEES+AD-MSCs, (2) CEES+CM-MSCs, (3) CEES, and (4) control. The model observation time was divided into 7 days for the short and 6 months for the long term. AD-MSCs were injected into mice via intraperitoneal injection 24 hours after CEES exposure. The therapeutic effects of AD-MSCs on pulmonary tissue damage were assessed using a histopathologic assay, measuring the neutrophil count, and bronchial alveolar lavage fluid (BALF) protein level. The levels of inflammatory and anti-inflammatory cytokines were evaluated using the enzyme-linked immunosorbent assay as the outcomes of interest. Lung damage progression was reduced by AD-MSC treatment in mice after CEES injection into the peritoneum. The proportion of CD11b+F4/80+ macrophages in the peritoneum was significantly lowered by AD-MSC treatment following CEES exposure. AD-MSC administration also reduced the level of pro-inflammatory cytokines, BALF protein, and nitric oxide levels in the peritoneal cavity. By reducing inflammation and enhancing tissue healing, AD-MSCs and CM-MSC help prevent acute lung damage caused by CEES. The current study supports the use of a mouse model as a solid experimental foundation and indicates potential use for future cell treatment.

Characteristics of different pathogenic bacterial infections and their effects on prognosis in adult patients with bronchiectasis.

The present study aimed to analyse the types of pathogens infecting adults with bronchiectasis and the effects of different pathogens on the number of acute exacerbations and the length of hospitalization for 1 year in patients with severe bronchiectasis. A total of 522 patients with bronchiectasis admitted to the Department of Respiratory and Critical Care Medicine at the Second Hospital of Jiaxing (Zhejiang, China) between January 2019 and December 2022 were retrospectively analysed. The patients were divided into a mild to moderate group and a severe group according to the bronchiectasis severity index criteria. The basic and clinical information of all the patients was collected. The patients were followed up for 1 year after the day when the sputum or alveolar lavage fluid samples tested positive for pathogens. The follow-up information included the exacerbation of cough symptoms, the number of hospitalizations and the number of days of antibiotic use in patients with bronchiectasis. A total of 522 patients with bronchiectasis were positive for pathogens, including 192 patients with Pseudomonas aeruginosa (P. aeruginosa; 36.8%), 60 patients with Klebsiella pneumoniae (K. pneumoniae; 11.5%), 48 patients with mixed pathogens (≥2 pathogens at the same time; 9.2%), 36 patients with Staphylococcus aureus (6.9%), 33 patients with Aspergillus fumigatus (6.3%), 30 patients with Haemophilus influenzae (5.7%), 15 patients with Acinetobacter baumannii (A. baumannii; 2.9%) and 108 patients with other pathogens (20.7%). Compared with patients with mild to moderate bronchiectasis, patients with severe bronchiectasis were more likely to have P. aeruginosa but less likely to have K. pneumoniae and other pathogens. The length of hospitalization and duration of antibiotic use in the severe group of patients with bronchiectasis caused by P. aeruginosa, A. fumigatus, or A. baumannii were significantly longer than those in the mild to moderate group. During the 1-year follow-up, the number of acute exacerbations and hospitalizations of patients with severe bronchiectasis caused by A. baumannii and P. aeruginosa were significantly greater than those of patients with severe bronchiectasis caused by other pathogens. According to logistic regression analysis, A. baumannii and P. aeruginosa were independent risk factors for acute exacerbation of severe bronchiectasis in the following year. In patients with severe bronchiectasis, the pathogens A. baumannii, P. aeruginosa and A. fumigatus were independent risk factors for future acute exacerbations and increased risk of hospitalization.

Inhalation of Microplastics Induces Inflammatory Injuries in Multiple Murine Organs via the Toll-like Receptor Pathway.

Previous studies have detected microplastics (MPs) in human biological samples, such as lungs, alveolar lavage fluid, and thrombus. However, whether MPs induce health effects after inhalation are unclear. In this study, fluorescent polystyrene microplastics (PS-MPs) were found in the thymus, spleen, testes, liver, kidneys, and brain on day 1 or day 3 after one intratracheal instillation. Furthermore, mice showed inflammation in multiple organs, manifested as obvious infiltration of neutrophils and macrophages, increased Toll-like receptors (TLRs), myeloid differentiation primary response protein 88 (MyD88) and nuclear factor-κB (NF-κB), as well as proinflammatory cytokines (tumor necrosis factor (TNF)-α and interleukin (IL)-1β) in the lungs, thymus, spleen, liver, and kidneys after four intratracheal instillations of PS-MPs at once every 2 weeks. Hepatic and renal function indexes were also increased. Subsequently, the inflammatory response in multiple murine organs was significantly alleviated by TLR2 and TLR4 inhibitors. Unexpectedly, we did not find any elevated secretion of monocyte chemotactic protein (MCP)-1 or TNF-α by RAW264.7 macrophages in vitro. Thus, PS-MPs induced inflammatory injuries in multiple murine organs via the TLRs/MyD88/NF-κB pathway in vivo, but not macrophages in vitro. These results may provide theoretical support for healthy protection against PS-MPs and their environmental risk assessment.

The Thyroid Hormone Analog GC-1 Mitigates Acute Lung Injury by Inhibiting M1 Macrophage Polarization.

Acute lung injury (ALI)/acute respiratory distress syndrome (ARDS) is a life-threatening condition with a high mortality rate of ≈40%. Thyroid hormones (THs) play crucial roles in maintaining homeostasis of the cellular microenvironment under stress. The previous studies confirmed that the clinical-stage TH analog GC-1 significantly alleviates pulmonary fibrosis by improving the function of mitochondria in epithelial cells. However, the effects of GC-1 on macrophages in lung injury and the related mechanisms remain unclear. This study evaluated the therapeutic effects of GC-1 in two murine models of lipopolysaccharide (LPS)- or hydrochloric acid (HCl)-induced ALI. Additionally, mouse alveolar macrophages (AMs) and human THP-1-derived macrophages are utilized to investigate the impact of GC-1 on macrophage polarization. GC-1 effectively reduces the inflammatory response and lung injury in ALI mice, as evidenced by neutrophil infiltration, cytokine levels, alveolar fluid clearance, and pulmonary pathology. Notably, GC-1 selectively inhibits M1 macrophage polarization, which may be achieved by impeding NF-κB signaling activation through the DNMT3b-PPARγ-NF-κB pathway in a TH receptor β1 (TRβ1)-dependent manner, consequently suppressing the polarization of macrophages toward the M1 phenotype and overproduction of inflammatory cytokines. Overall, these findings highlight the immunomodulatory property of GC-1 as an anti-inflammatory strategy for ALI/ARDS and inflammation-related diseases.

B-204 A Real-time Probe-based PCR Assay for Detection of Pneumocystis Pneumonia

Abstract Background Pneumocystis jirovecii is an atypical opportunistic fungus with lung tropism and worldwide distribution that continues to be one of the major opportunistic pathogens causing severe Pneumocystis pneumonia (PcP) in individuals with acquired immune deficiency syndrome (AIDS) and patients with immunosuppression due to other causes. Widespread prophylaxis and treatment for P. jirovecii with sulfa drugs have decreased the incidence of PcP, but concerns have been raised about the possible emergence of P. jirovecii isolates resistant to these drugs. Point mutations in this gene have been associated with prior exposure to sulfa drugs in other microorganisms, the polymorphic positions 165 and 171, which lead to an amino acid change at positions 55 (Thr55Ala) and 57 (Pro57Ser) of the polypeptide chain, respectively. Fluorescent PCR technology can detect the nucleic acid fragments of P. jirovecii in patients' serum, alveolar perfusion fluid (BALF) and tissue samples, and further identify drug-resistant mutations, which is of great significance for early clinical and accurate initiation of antifungal therapy. MycoMDx Pneumocystis Jirovecii PCR Assay is the use of PCR-fluorescence probe method, combined with other methods to achieve the auxiliary diagnosis of P. jirovecii infection and resistance to sulfonamides (Fig. 1). Methods In this study, we did a performance evaluation of the MycoMDx Pneumocystis Jirovecii PCR Assay (CE-approved), including diagnostic sensitivity and specificity, the limit of detection (LoD), precision and stability. The above PCR assay reagents were developed and produced by Dynamiker Biotechnology (Tianjin) Co., Ltd. Results The sensitivity and specificity of the PCR assay reagents were above 90%, the LoD was 1000 copies/mL, and the precision and stability were in accordance with the requirements (CV≤5%). Conclusions The MycoMDx Pneumocystis Jirovecii PCR Assay has great clinical value by providing a rapid and reliable test to aid in early diagnosis.

Curcumin Alleviates Airway Inflammation in Cough-Variant Asthmatic Rats by Modulating M1/M2 Macrophage Polarization.

With the increase of environmental pollution and atypical pathogen infections, the incidence of cough variant asthma (CVA) has been increasing annually, making it a pressing issue of the medical community. This study aims to observe the ameliorative effect of curcumin on a rat model of cough variant asthma. A rat model of cough variant asthma was induced by sensitization with ovalbumin combined with aluminum hydroxide (Al(OH)3), followed by repeated excitations. The drug was administered on the day of the initial nebulized attack, and gavage was administered for 14 d. Pathological changes in the lung tissues were observed, along with the assessment of cough susceptibility and airway resistance. The number of inflammatory cell eosinophils and leukocytes were determined in alveolar lavage fluid. Additionally, serum inflammatory factors and lung tissues Matrix Metalloproteinase-9 (MMP-9) protein were assessed. The level of M1/M2 macrophages was also detected. Following the administration of curcumin, there was reduced inflammatory infiltration, less disordered arrangement of the lung tissue, and decreased abnormal proliferation of lung tissues in cough variant asthma rats compared to the model group. Curcumin treatment led toa notable reduction in cough frequency, a significant decrease in pro-inflammatory factor concentration levels in serum and inflammatory cell counts in the alveolar lavage fluid, and a marked increase in anti-inflammatory factor levels (p < 0.05). Additionally, curcumin administration led to a significant increase in M2-type macrophage levels, while simultaneously decreasing the levels of M1-type macrophages (p < 0.05). The administration of curcumin effectively ameliorates ovalbumin-induced airway inflammation in cough-variant asthma rats. This effect is attributed to modulating macrophage polarization towards the anti-inflammatory M2 phenotype, thereby reducing airway inflammation, airway hyperresponsiveness, and lung tissue injury.

Flow topology and mixing in alveolar edema: Unsteady flow in interconnected cavities with moving walls

The study of alveolar fluid mechanics is critical for comprehending respiratory function and lung diseases, particularly in cases of alveolar lesions that result in significant structural and fluid dynamic changes. This study investigates the flow topology and chaotic mixing within both normal and edematous alveoli, where the alveoli in the edematous model are interconnected by pores. To numerically simulate alveolar flow, a mathematical model is developed to ascertain the key parameters of Reynolds number (Re) and alveolar expansion ratio. Subsequently, the flow fields are analyzed to determine wall shear stress (WSS) and to identify WSS critical points and critical points of velocity vector, with a thorough presentation of the various flow topologies corresponding to these critical points. Moreover, a dynamic mode decomposition-based method is introduced to track particle trajectories, and the exploration of chaotic mixing is conducted through tracer advection, Poincare map, and the calculation of finite-time Lyapunov exponents. Results indicate that the edematous model exhibits a higher Re and higher WSS due to the fluid properties. Within the alveoli, high WSS is usually localized at the pores. The pores increase critical points and alter flow topologies, significantly changing chaotic mixing. Additionally, Re and alveolar locations also affect mixing patterns. These findings are crucial for understanding alveolar physiology and designing inhaled drugs for lung diseases, considering the role of chaos in particle transport in the lung acini.

Research on ameliorating pulmonary fibrosis in silicosis mice of Cordyceps cicadae polysaccharides

Objective: A mouse silicosis model was constructed by injecting silicon dioxide (SiO(2)) particles into the trachea to explore the effect and mechanism of Cordyceps cicadae polysaccharides (CCP) on ameliorating pulmonary fibrosis in silicosis mice. Methods: In May 2023, CCP were extracted and isolated, the monosaccharide composition and functional group composition were analyzed by high performance liquid chromatography and Fourier transform infrared spectroscopy. C57BL/6J mice were injected with 50 μl 50 mg/ml SiO(2) suspension to construct silicosis mouse model, which were then randomly divided into model group, CCP intervention groups [low dose group (LCCP group), medium dose group (MCCP group) and high dose group (HCCP group) ], the control group was administered by physiological saline, 8 mice in each group. Mice in the CCP intervention groups received oral gavage administration once daily with CCP solution (100, 200 and 400 mg/kg), while control group and model group received physiological saline, lasted for 30 days. The body weight of mice was recorded and the lung coefficient was calculated. The pathomorphological changes of mouse lung tissue were determined by HE and Masson staining. The contents of fibrosis indexes [hydroxyproline acid (HYP), connective tissue growth factor (CTGF) and matrix metallopeptidase 2 (MMP-2) ] of lung tissue and the pro-inflammatory factors[tumor necrosis factor-alpha (TNF-α), interleukin-1 beta (IL-1β) and interleukin-6 (IL-6) ] of lung tissue and alveolar lavage fluid were determined by ELISA. The expression level of Collagen Ⅰ was determined by immunohistochemistry. The relative protein expression levels of transforming growth factor-β1 (TGF-β1), P-Smad2, α-smooth muscle actin (α-SMA), Toll-like receptor 4 (TLR4), nuclear factor kappa-B p65 (NF-κBp65) and myeloid differentiation primary response gene 88 (MyD88) in lung tissue were determined by Western blot. Results: The total sugar content of the CCP was 86.78%, composed of D-mannose, D-rhamnose, D-glucose and D-galactose, with a molar ratio of 12.71∶1.53∶1.00∶12.64. The infrared spectrum indicated the characteristic groups of its polysaccharides. Compared with the control group, the body weight of mice in the model group was decreased, lung coefficient was increased, the contents of HYP, CTGF and MMP-2 in lung tissue were increased, and the contents of TNF-α, IL-1β and IL-6 in lung tissue and alveolar lavage fluid were increased (P<0.05). The mice lung showed massive inflammatory cell infiltration and collagen fiber deposition, and the silicosis fibrosis was severe. The expression of CollagenⅠin lung tissue of model group was increased, and the proteins expression levels of TGF-β1, P-Smad2/Smad2, α-SMA, TLR4, NF-κBp65 and MyD88 were increased in mouse lung tissue (P<0.05). Compared with the model group, the body weights of mice in the MCCP and HCCP groups were increased, the lung coefficients were decreased, the contents of HYP, CTGF and MMP-2 in lung tissue were decreased, and the contents of TNF-α, IL-1β and IL-6 in lung tissue and alveolar lavage fluid were decreased (P<0.05). The inflammatory cell infiltration in the lung was reduced, and the degree of fibrosis was improved to varying degrees. The expression level of CollagenⅠwas down-regulated in the lung tissue of MCCP and HCCP groups, and the protein expression levels of TGF-β1, P-Smad2/Smad2, α-SMA, TLR4, NF-κBp65 and MyD88 were decreased in lung tissue (P<0.05) . Conclusion: The CCP could reduce the levels of fibrosis-related indicators and pro-inflammatory factors in lung tissue, ameliorating mouse lung inflammation and silicosis fibrosis caused by SiO(2) particles by inhibiting the activation of TGF-β1/Smad pathway and TLR4/nuclear factor kappa-B (NF-κB) pathway.

Different allergen-induced asthma and anaphylaxis show distinctive IgE pathway dependence

BackgroundThe pathogenesis of allergic asthma is classically understood to involve allergens crosslinking Immunoglobulin E (IgE) bound to mast cells, leading to the release of histamine and other inflammatory mediators. ObjectiveThis study aims to explore whether different allergens have distinct IgE-dependent mechanisms in mouse models of both asthma and anaphylaxis. MethodsWild type (WT) and IgE knockout (IgE KO) mice were used to generate asthma mouse models. Lung inflammation was assessed by histological analysis and inflammatory cells in Bronchial Alveolar Lavage Fluids (BALF). Passive Cutaneous Anaphylaxis (PCA) was conducted to quantify IgE, and Toluidine Blue staining was used to visualize mast cell recruitment. ResultsAll allergen-treated mice exhibited significant airway inflammation. Compared to WT mice, HDM-treated IgE KO mice showed an attenuated inflammatory profile, particularly with reduced eosinophils. These mice had lower serum levels of HDM-specific IgE and IgG1 as well as reduced levels of Th2 cytokines interleukin 4 (IL-4) and IL-5 in BALF. CRE-treated IgE KO mice also displayed a reduced inflammation, with significant differences only in eosinophils. Interestingly, no significant differences in airway inflammation were observed between OVA-treated IgE KO mice and WT mice. Furthermore, both HDM and CRE-induced PCA model showed significantly less Evan's blue dye leakage and mast cell recruitment in the ears of IgE KO mice compared to WT mice, with no differences for OVA-induced PCA and mast cell recruitment. ConclusionThe results highlight the variability in IgE pathway dependence among different allergens, emphasizing the need for further research to delineate the underlying mechanisms.

Development of a Rapid Fluorescence Probe for the Determination of Aqueous Hypochlorite

Chlorine interacts with aqueous environments, including the mucosa and alveolar fluid in the lungs, causing its the immediate transformation to hypochlorous acid (HClO) and hydrochloric acid (HCl) which induces cellular damage and may produce systemic toxicity. There are multiple techniques to monitor hypochlorite (HClO/ClO−) from various matrices, however, they each have significant disadvantages, including limited sensitivity, complexity, and slow response. In this study, we developed a water-soluble fluorescein-based probe, called fluorescein thioacid (FSH), for the rapid and sensitive detection of HClO/ClO− in aqueous solutions via oxidation of FSH to produce fluorescein. FSH was synthesized via a simple, one-step procedure and exhibited excellent selectivity for ClO−, maintaining 82% signal stability for 24 h. FSH performed well over a wide pH range (4–10; optimum pH of 4), produced a linear range from 1 to 100 µM, and had a detection limit of 100 nM. The probe was able to accurately quantify HClO/ClO− concentrations in tap water (13.8 μM) and swimming pool water (56.9 μM) samples. Overall, FSH is simple to synthesize, highly selective, highly sensitive, has excellent water solubility, and produces a fast response for monitoring of aqueous ClO− levels.

A case of necrotic pneumonia caused by Streptococcus pneumoniae was diagnosed using a pneumonia antigen test in BALF: A case report.

Streptococcus pneumoniae is a common cause of community-acquired pneumonia. Currently, it is believed that many cases of pulmonary infection with negative results on pathogenic testing are caused by S. pneumoniae. There have been no reports of the detection of S. pneumoniae antigen in lung lavage fluid. An elderly male patient with suboptimal fasting blood glucose control and a history of liver abscess. Chest computed tomography (CT) revealed inflammatory lesions in both lungs with consolidation in the middle lobe of the right lung. After admission, we collected alveolar lavage fluid in a timely manner and performed pneumococcal antigen detection and etiological testing. Prompt testing for pneumococcal antigen in bronchoalveolar lavage fluid yielded a positive clinical outcome. Subsequent analysis via bacterial culture of sputum and next-generation sequencing (mNGS) of BALF definitively identified S. pneumoniae as the etiological agent. Following the analysis of drug sensitivity test results from the identified pathogens, adjustments were made to the antibiotic regimen, and appropriate pus puncture drainage was performed. Subsequently, the patient's condition improved, leading to discharge. The identification of S. pneumoniae antigen in bronchoalveolar lavage fluid may facilitate earlier and more precise diagnosis of pneumonia attributed to S. pneumoniae.

Good syndrome combined with multiple microbial pulmonary infections: case report and review of the literature.

Good syndrome (GS), a rare acquired immunodeficiency disorder characterized by thymoma and hypogammaglobulinemia, predisposes individuals to recurrent infections. This study reports a case of a 37-year-old male GS with multiple pulmonary infections and reviews relevant literature. The patient, with a history of thymoma resection, experienced multiple hospitalizations due to lung infections and neutropenia. The alveolar lavage fluid was detected by macro-genomic sequencing (NGS) to detect multiple pathogens, and targeted anti-infective and immunity-enhancing treatments led to improved symptoms and normal neutrophil counts. A literature review of 98 case reports from 2000 to 2023 was conducted, summarizing the associated diseases and pathogens in GS patients. Regular immunoglobulin monitoring in thymoma patients is essential for early GS diagnosis. When empirical antimicrobial therapy fails, mNGS for pathogen detection and targeted therapy are crucial, and regular IVIG injections can reduce infection rates in GS patients.

Changes of lung function and inflammatory factors in rat models of coal workers' pneumoconiosis

Objective: To observe the changes of lung function and inflammatory factors in rat models of coal workers' pneumoconiosis at different time points. Methods: In June 2021, 96 healthy male SD rats with SPF grade were divided into 1, 3, and 6-month control group and dust staining group (coal dust group, coal silica dust group, quartz group) according to random number table method, with 8 rats in each group. After one week of adaptive feeding, a one-time non-exposed tracheal perfusion method (1 ml/ piece) was used. The dust dyeing group was given 50 g/L coal dust, coal silica mixed dust and quartz dust suspension, respectively, and the control group was given 0.9% normal saline solution. At 1, 3 and 6 months after perfusion, lung function was detected by animal lung function apparatus, then all lung tissues and alveolar lavage fluid were killed, and lung histopathological morphological changes were observed by HE staining, and the contents of interleukin (IL-1β), IL-18, IL-4 and IL-10 in alveolar lavage fluid were detected by ELISA. One-way analysis of variance was used to compare groups. Two factors (inter-group treatment factor (4 levels) and observation time factor (3 levels) ) were used in the analysis of the effects of inter-group treatment and treatment time on related indicators. Results: HE staining results showed that coal spot appeared in the lung tissue of coal dust group, coal spot and coal silicon nodule appeared in the lung tissue of coal dust group, and silicon nodule appeared in the lung tissue of quartz group. Compared with the control group, the forced vital capacity (FVC) and forced expiratory volume at 0.2 second (FEV(0.2)) of rats in the dust staining group had interaction between the treatment and treatment time (P<0.05). With the increase of dust dyeing time, FVC and FEV(0.2) decreased significantly at 3-6 months of dust dyeing, and the maximum gas volume per minute (MVV) decreased significantly at 1-3 months of dust dyeing (P<0.05). The lowest lung function index was in quartz group, followed by coal-silica group and coal-dust group. There were statistically significant differences in the main effect and interaction effect of the pro-inflammatory factor IL-18 among all groups in treatment and treatment time (IL-18: F=70.79, 45.97, 5.90, P<0.001), and interaction existed. The highest content of inflammatory factors in alveolar lavage fluid of all dust groups was quartz group, followed by coal silica group and coal dust group. There were significant differences in the main effect and interaction effect of anti-inflammatory factors between groups and treatment time (IL-4: F=41.55, 33.01, 5.23, P<0.001, <0.001, <0.001; IL-10: F=7.46, 20.80, 2.91, P=0.002, <0.001, 0.024), and there was interaction. The highest content of anti-inflammatory factor was in quartz group, followed by coal silica group and coal dust group. Conclusion: Lung function decreased and levels of inflammatory fators increased in rat models of coal workers' pneumoconiosis, with the quartz group being the most severely damaged. Lung function is mainly impaired in thrid-six months, and the content of inflammatory factors begins to change in first-thrid months. MVV are the earliest and most obvious in lung function. IL-18 is suitable for monitoring changes in the pro-inflammatory response of coal workers' pneumoconiosis, and IL-10 is suitable for monitoring changes in anti-inflammatory response.

Pulmonary benign metastasizing leiomyoma presenting as acute hypoxemic respiratory failure: a case report

Pulmonary benign metastasizing leiomyoma is an uncommon condition, predominantly affecting women of childbearing age with a history of uterine smooth muscle tumors and uterine leiomyoma surgery for uterine leiomyoma. The progression of PBML is often unpredictable and depends on the extent of lung involvement. Generally, most patients remain asymptomatic, but a minority may experience coughing, wheezing, or shortness of breath, which are frequently misdiagnosed as pneumonia. consequently, this presents significant challenges in both treatment and nursing care before diagnosis. This paper reports the case of a 35-year-old woman primarily diagnosed with acute hypoxic respiratory failure who was transferred from the emergency room to the intensive care unit. The initial computed tomography scan of the patient’s lungs indicated diffuse interstitial pneumonia, but the sequencing of the alveolar lavage fluid pathogen macro did not detect any bacteria, fungi, or viruses. Moreover, the patient remained in a persistent hypoxic state before the definitive diagnosis. Therefore, our focus was on maintaining the airway patency of the patient, using prone ventilation, inhaling nitric oxide, monitoring electrical impedance tomography, and preventing ventilator-associated pneumonia to improve oxygenation, while awaiting immunohistochemical staining of the patient’s biopsied lung tissue. This would help us clarify the diagnosis and treat it based on etiology. After meticulous treatment and nursing care, the patient was weaned off the ventilator after 26 days and transferred to the respiratory ward after 40 days. This case study may serve as a reference for clinical practice and assist patients suffering from PBML.