Cinnamaldehyde: an effective component of Cinnamomum cassia inhibiting Helicobacter pylori.

ETHNOPHARMACOLOGICAL RELEVANCE: Cinnamomum cassia Presl (Cinnamomum cassia) is a common traditional Chinese medicine, which can promote the secretion and digestion of gastric juice, improve the function of gastrointestinal tract. Cinnamaldehyde (CA) is a synthetic food flavoring in the Chinese Pharmacopoeia. AIM OF THE STUDY: This study aimed to search for the active ingredient (CA) of inhibiting H. pylori from Cinnamomum cassia, and elucidate mechanism of action, so as to provide the experimental basis for the treatment of H. pylori infection with Cinnamomum cassia. MATERIALS AND METHODS: It's in vitro and in vivo pharmacological properties were evaluated based on minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), and an acute gastric inflammation model in mice infected with H. pylori. Drug safety was evaluated using the CCK8 method and high-dose administration in mice. The advantageous characteristics of CA in inhibiting H. pylori were confirmed using acidic conditions and in combination with the antibiotics. The mechanism underlying the action of CA on H. pylori was explored using scanning electron microscopy (SEM), adhesion experiments, biofilm inhibition tests, ATP and ROS release experiments, and drug affinity responsive target stability (DARTS) screening of target proteins. The protein function and target genes were verified by molecular docking and Real-Time quantitative reverse transcription PCR (qRT-PCR). RESULTS: The results demonstrated that CA was found to be the main active ingredient against H. pylori in Cinnamomum cassia in-vitro tests, with a MIC of 8-16 µg/mL. Moreover, CA effectively inhibited both sensitive and resistant H. pylori strains. The dual therapy of PPI + CA exhibited remarkable in vivo efficacy in the acute gastritis mouse model, superior to the standard triple therapy. DARTS, molecular docking, and qRT-PCR results suggested that the target sites of action were closely associated with GyrA, GyrB, AtpA, and TopA, which made DNA replication and transcription impossible, then leading to inhibition of bacterial adhesion and colonization, suppression of biofilm formation, and inhibition ATP and enhancing ROS. CONCLUSIONS: This study demonstrated the suitability of CA as a promising lead drug against H. pylori, The main mechanisms can target GyrA ect, leading to reduce ATP and produce ROS, which induces the apoptosis of bacterial.

Endovascular Repair and Prognosis of Patients with Brucella abortus Infection-Induced Aorto-Iliac Aneurysm.

Objective: To establish the endovascular repair and prognosis of patients with aorto-iliac aneurysm and Brucella abortus infection. Methods: From September 2018 to September 2021, seven cases of Brucella abortus infection with aorto-iliac aneurysm were treated by the endovascular aneurysm repair (EVAR) procedure. Clinical and imaging data were collected to evaluate the therapeutic results, including body temperature, blood culture, imaging manifestations, stent patency and endoleak during the postoperative and follow-up periods. Results: Except for one patient who died of acute hematemesis and hematochezia just after the admission, seven patients were treated successfully. The aneurysms were completely excluded, and all stent grafts were patent. Patients were followed up for 12-32 months, with an average follow-up of 18.5 ± 9.1 months. There were no cases of endoleak, infection recurrence, gluteal muscle ischemia or spinal cord ischemia during the follow-up period. Conclusion: It is feasible to treat Brucella abortus-infected aneurysms with the EVAR procedure. The results were optimistic in the short and medium-term. The application of sensitive antibiotics before and after the operation is the cornerstone of endovascular therapy. However, the long-term results require further follow-up.

Dalbavancin for Acute Bacterial Skin and Skin Structure Infections in Pediatrics: Insights from Continuation Therapy Experience.

Acute Bacterial Skin and Skin Structure Infections (ABSSSI) are marked by substantial morbidity, frequent need for hospitalization, and long courses of intravenous antibiotic therapy. Herein, we report four cases of pediatric patients admitted for ABSSSI and managed with a combination antibiotic regimen incorporating dalbavancin: a second-generation lipoglycopeptide active against Gram-positive bacteria, including methicillin-resistant Staphylococcus aureus. In our experience, particularly in a setting with a high methicillin-resistance rate, dalbavancin demonstrated safety and efficacy, simplifying ABSSSI management in childhood. Its prolonged half-life enables a single-dose administration regimen, offering potential solutions to numerous challenges encountered in pediatric care, such as extended hospital stays, difficulties in securing and maintaining vascular access, lack of pediatric-specific drug indications, and limited availability of suitable oral formulations.

Synthesis and preclinical evaluation of novel 18F-vancomycin-based tracers for the detection of bacterial infections using positron emission tomography.

INTRODUCTION: Bacterial infections are a major problem in medicine, and the rapid and accurate detection of such infections is essential for optimal patient outcome. Bacterial infections can be diagnosed by nuclear imaging, but most currently available modalities are unable to discriminate infection from sterile inflammation. Bacteria-targeted positron emission tomography (PET) tracers have the potential to overcome this hurdle. In the present study, we compared three 18F-labelled PET tracers based on the clinically applied antibiotic vancomycin for targeted imaging of Gram-positive bacteria. METHODS: [18F]FB-NHS and [18F]BODIPY-FL-NHS were conjugated to vancomycin. The resulting conjugates, together with our previously developed [18F]PQ-VE1-vancomycin, were tested for stability, lipophilicity, selective binding to Gram-positive bacteria, antimicrobial activity and biodistribution. For the first time, the pharmacokinetic properties of all three tracers were compared in healthy animals to identify potential binding sites. RESULTS: [18F]FB-vancomycin, [18F]BODIPY-FL-vancomycin, and [18F]PQ-VE1-vancomycin were successfully synthesized with radiochemical yields of 11.7%, 2.6%, and 0.8%, respectively. [18F]FB-vancomycin exhibited poor in vitro and in vivo stability and, accordingly, no bacterial binding. In contrast, [18F]BODIPY-FL-vancomycin and [18F]PQ-VE1-vancomycin showed strong and specific binding to Gram-positive bacteria, including methicillin-resistant Staphylococcus aureus (MRSA), which was outcompeted by unlabeled vancomycin only at concentrations exceeding clinically relevant vancomycin blood levels. Biodistribution showed renal clearance of [18F]PQ-VE1-vancomycin and [18F]BODIPY-FL-vancomycin with low non-specific accumulation in muscles, fat and bones. CONCLUSION: Here we present the synthesis and first evaluation of the vancomycin-based PET tracers [18F]BODIPY-FL-vancomycin and [18F]PQ-VE1-vancomycin for image-guided detection of Gram-positive bacteria. Our study paves the way towards real-time bacteria-targeted diagnosis of soft tissue and implant-associated infections that are oftentimes caused by Gram-positive bacteria, even after prophylactic treatment with vancomycin.

Efficacy and safety of generic cefoperazone/sulbactam versus branded cefoperazone/sulbactam in the treatment of bacterial infections: a systematic review and meta-analysis.

This study aim to assess the clinical efficacy and safety of generic cefoperazone/sulbactam compared to the branded cefoperazone/sulbactam (Sulperazon) in treating bacterial infections through a meta-analysis. Searches were conducted across PubMed, Embase, Cochrane Library, CNKI, WanFang, VIP databases, and Clinical Trials database, resulting in the inclusion of 11 studies comprising 7 randomized controlled trials (RCTs) and 4 retrospective cohort studies (RCSs). Meta-analysis of the RCTs indicated no statistical differences in clinical success rates, clinical cure rates, microbiological eradication rates, and incidence of adverse reactions between the generic cefoperazone/sulbactam and the branded version. Findings from the RCSs aligned with those from the RCTs, demonstrating that generic versions of cefoperazone/sulbactam are equivalent in efficacy and safety to their branded counterparts in treating bacterial infections.

Efficacy and Safety of Oral and IV Levonadifloxacin Therapy in Management of Bacterial Infections: Findings of a Prospective, Observational, Multi-center, Post-marketing Surveillance Study.

Background Antimicrobial resistance by bacteria poses a substantial threat to morbidity and mortality worldwide, and treatment of resistant infections is a challenge for the treating clinician. Levonadifloxacin is a novel broad-spectrum agent belonging to the benzoquinolizine subclass of quinolone, which can be used by both oral and intravenous administration for the treatment of infections caused by gram-positive organisms, including methicillin-resistant Staphylococcus aureus (MRSA). Patients and methods This prescription event monitoring study captured data from 1266 patients receiving levonadifloxacin (oral and/or IV) in a real-world setting to assess the safety and efficacy in the treatment of various bacterial infections. The duration of the study was 18 months. Study outcomes were clinical success and microbial success at the end of therapy. Global assessments were done for safety and efficacy at the end of therapy using a 5-point Likert scale (excellent, very good, good, satisfactory, and poor). Results The mean (median) duration of therapy was 7.2 (7.0) days, with a median time to clinical improvement of four days. Oral therapy was administered to 224 patients; 940 received IV, and 102 received IV followed by oral therapy. Patients were prescribed levonadifloxacin for gram-positive infections, skin and soft tissue infections, diabetic foot infections, septicemia, catheter-related blood-stream infections, bone and joint infections, febrile neutropenia, and respiratory infections, including COVID-19 pneumonia. The clinical cure on the eighth day was 95.7%, whereas the microbial success on the eighth day was 93.3% (n=60). For different types of infections, the clinical success rates ranged from 85.2% to 100%. There were only 30 treatment-emergent adverse events reported in 29 patients. Overall, about 95.6% of patients rated the efficacy as good to excellent, whereas only 3.8% of patients rated it satisfactory; for safety, 95.7% of patients rated it as good to excellent, with only 3.9% of patients rated it as satisfactory. Conclusions The excellent safety and efficacy profile of levonadifloxacin, when administered as an oral or intravenous therapy, makes it a desirable treatment modality for the management of various bacterial infections, including those caused by resistant pathogens such as MRSA and quinolone-resistant Staphylococcus aureus (QRSA). Features of levonadifloxacin, such as availability in both IV and oral form, minimal drug-drug interactions, lack of the need to adjust dosages in renal and hepatically impaired patients along with a broad spectrum of coverage, make it a suitable agent that meets several unmet clinical needs of physicians.

16S rRNA seq-identified Corynebacterium promotes pyroptosis to aggravate diabetic foot ulcer.

BACKGROUND: Diabetic foot ulcer (DFU) is one of the main chronic complications caused by diabetes, leading to amputation in severe cases. Bacterial infection affects the wound healing in DFU. METHODS: DFU patients who met the criteria were selected, and the clinical data were recorded in detail. The pus exudate from the patient's foot wound and venous blood were collected for biochemical analysis. The distribution of bacterial flora in pus exudates of patients was analyzed by 16S rRNA sequencing, and the correlation between DFU and pathogenic variables, pyroptosis and immunity was analyzed by statistical analysis. Then, the effects of key bacteria on the inflammation, proliferation, apoptosis, and pyroptosis of polymorphonuclear leukocytes were investigated by ELISA, CCK-8, flow cytometry, RT-qPCR and western blot. RESULTS: Clinical data analysis showed that Wagner score was positively correlated with the level of inflammatory factors, and there was high CD3+, CD4+, and low CD8+ levels in DFU patients with high Wagner score. Through alpha, beta diversity analysis and species composition analysis, Corynebacterium accounted for a large proportion in DFU. Logistics regression model and Person correlation analysis demonstrated that mixed bacterial infections could aggravate foot ulcer, and the number of bacteria was closely related to inflammatory factors PCT, PRT, immune cells CD8+, and pyroptosis-related proteins GSDMD and NLRP3. Through in vitro experiments, Corynebacterium inhibited cell proliferation, promoted inflammation (TNF-α, PCT, CRP), apoptosis and pyroptosis (IL-1ß, LDH, IL-18, GSDMD, NLRP3, and caspase-3). CONCLUSION: Mixed bacterial infections exacerbate DFU progression with a high predominance of Corynebacterium, and Corynebacterium promotes inflammation, apoptosis and pyroptosis to inhibit DFU healing.

Pseudomonas putida infection induces immune-antioxidant, hepato-renal, ethological, and histopathological/immunohistochemical disruptions in Oreochromis niloticus: the palliative role of titanium dioxide nanogel.

BACKGROUND: Pseudomonas putida is a pathogenic bacterium that induces great losses in fishes, including Nile tilapia (Oreochromis niloticus). Currently, the application of nanomaterials in aquaculture practices has gained more success as it endows promising results in therapies compared to traditional protocols. OBJECTIVE: Therefore, the current perspective is considered the first report to assess the anti-bacterial efficacy of titanium dioxide nanogel (TDNG) against Pseudomonas putida (P. putida) in Nile tilapia. METHODS: The fish (n = 200; average body weight: 47.50±1.32 g) were allocated into four random groups (control, TDNG, P. putida, and TDNG + P. putida), where 0.9 mg/L of TDNG was applied as bath treatment for ten days. RESULTS: Outcomes revealed that P. putida infection caused ethological alterations (surfacing, abnormal movement, and aggression) and depression of immune-antioxidant variables (complement 3, lysozyme activity, total antioxidant capacity, superoxide dismutase, and reduced glutathione content). Additionally, a substantial elevation in hepatorenal biomarkers (aspartate and alanine aminotransferases and creatinine) with clear histopathological changes and immuno-histochemical alterations (very weak BCL-2 and potent caspase-3 immuno-expressions) were seen. Surprisingly, treating P. putida-infected fish with TDNG improved these variables and obvious restoration of the tissue architectures. CONCLUSION: Overall, this report encompasses the key role of TDNG as an anti-bacterial agent for controlling P. putida infection and improving the health status of Nile tilapia.

Mitochondrial electron transport chain in macrophage reprogramming: Potential role in antibacterial immune response.

Macrophages restrain microbial infection and reinstate tissue homeostasis. The mitochondria govern macrophage metabolism and serve as pivot in innate immunity, thus acting as immunometabolic regulon. Metabolic pathways produce electron flows that end up in mitochondrial electron transport chain (mtETC), made of super-complexes regulating multitude of molecular and biochemical processes. Cell-intrinsic and extrinsic factors influence mtETC structure and function, impacting several aspects of macrophage immunity. These factors provide the macrophages with alternate fuel sources and metabolites, critical to gain functional competence and overcoming pathogenic stress. Mitochondrial reactive oxygen species (mtROS) and oxidative phosphorylation (OXPHOS) generated through the mtETC are important innate immune attributes, which help macrophages in mounting antibacterial responses. Recent studies have demonstrated the role of mtETC in governing mitochondrial dynamics and macrophage polarization (M1/M2). M1 macrophages are important for containing bacterial pathogens and M2 macrophages promote tissue repair and wound healing. Thus, mitochondrial bioenergetics and metabolism are intimately coupled with innate immunity. In this review, we have addressed mtETC function as innate rheostats that regulate macrophage reprogramming and innate immune responses. Advancement in this field encourages further exploration and provides potential novel macrophage-based therapeutic targets to control unsolicited inflammation.

Retrospective study of the incidence, risk factors, treatment outcomes of bacterial infections at uncommon sites in cirrhotic patients.

BACKGROUND: Bacterial infections (BI) negatively affect the natural course of cirrhosis. The most frequent BI are urinary tract infections (UTI), pneumonia, and spontaneous-bacterial peritonitis (SBP). AIM: To assess the relevance of bacterial infections beyond the commonly recognized types in patients with cirrhosis and to investigate their relationship with other clinical variables. METHODS: We retrospectively analyzed patients with cirrhosis and BI treated between 2015 and 2018 at our tertiary care center. BIs were classified as typical and atypical, and clinical as well as laboratory parameters were compared between the two groups. RESULTS: In a cohort of 488 patients with cirrhosis, we identified 225 typical BI (95 UTI, 73 SBP, 72 pulmonary infections) and 74 atypical BIs, predominantly cholangitis and soft tissue infections (21 each), followed by intra-abdominal BIs (n = 9), cholecystitis (n = 6), head/throat BIs (n = 6), osteoarticular BIs (n = 5), and endocarditis (n = 3). We did not observe differences concerning age, sex, or etiology of cirrhosis in patients with typical vs atypical BI. Atypical BIs were more common in patients with more advanced cirrhosis, as evidenced by Model of End Stage Liver Disease (15.1 ± 7.4 vs 12.9 ± 5.1; P = 0.005) and Child-Pugh scores (8.6 ± 2.5 vs 8.0 ± 2; P = 0.05). CONCLUSION: Atypical BIs in cirrhosis patients exhibit a distinct spectrum and are associated with more advanced stages of the disease. Hence, the work-up of cirrhosis patients with suspected BI requires detailed work-up to elucidate whether typical BI can be identified.

Disease burden of main bacterial infections in Japan, 2015-2020: A population-level study.

INTRODUCTION: Comprehensive evidence about the burden of infectious diseases in the Western Pacific Region is scarce. We thus examined the disease burden of infectious diseases in Japan in terms of disability-adjusted life years (DALYs). METHODS: We extracted national claims data from Japan's universal health insurance system to estimate the burden of disease for selected infections between 2015 and 2020 using DALYs. The mortality rate, disability duration and severity weight of each disease were estimated based on national data and literature reviews. RESULTS: Disease burden per 100,000 population was 1,307.0 in 2015 and 972.1 in 2020 for bloodstream infections (BSI), 796.5 DALYs in 2015 and 498.9 DALYs in 2020 for pneumonia, 171.5 in 2015 and 149.4 in 2020 for meningitis and 11.6 in 2015 and 11.4 in 2020 for urinary tract infections (UTI). Only surgical site infections (SSI) showed a slightly increasing trend over the 5-year period, from 2.2 in 2015 to 2.8 in 2020. CONCLUSIONS: Our results showed that the disease burden of the five major infectious diseases was higher in Japan than in other countries. However, while the burden of SSI increased, the burden of pneumonia, meningitis, BSI and UTI gradually decreased year on year. The possible causes of the decreased morbidity should be examined in future work.

[Urinary tract infection and overactive bladder. Is there an association?]

A discussion of key research findings dedicated to the relationship between urinary tract infection (UTI) and overactive bladder (OAB) is presented in the article. The results of the publications support the concept that UTI may be an underappreciated contributor to the development of OAB in some patients and vice versa. This information raises a number of questions regarding the treatment and diagnosis of OAB and UTI. The main question is the potential use of antibiotics, anti-inflammatory drugs, and other drugs in the treatment of patients with OAB, as well as the rationale for the use of therapy that normalize lower urinary tract (LUT) function in the presence of chronic recurrent UTI.

The use of faecal microbiota transplant as treatment for recurrent or refractory Clostridioides difficile infection and other potential indications: second edition of joint British Society of Gastroenterology (BSG) and Healthcare Infection Society (HIS) guidelines.

The first British Society of Gastroenterology (BSG) and Healthcare Infection Society (HIS)-endorsed faecal microbiota transplant (FMT) guidelines were published in 2018. Over the past 5 years, there has been considerable growth in the evidence base (including publication of outcomes from large national FMT registries), necessitating an updated critical review of the literature and a second edition of the BSG/HIS FMT guidelines. These have been produced in accordance with National Institute for Health and Care Excellence-accredited methodology, thus have particular relevance for UK-based clinicians, but are intended to be of pertinence internationally. This second edition of the guidelines have been divided into recommendations, good practice points and recommendations against certain practices. With respect to FMT for Clostridioides difficile infection (CDI), key focus areas centred around timing of administration, increasing clinical experience of encapsulated FMT preparations and optimising donor screening. The latter topic is of particular relevance given the COVID-19 pandemic, and cases of patient morbidity and mortality resulting from FMT-related pathogen transmission. The guidelines also considered emergent literature on the use of FMT in non-CDI settings (including both gastrointestinal and non-gastrointestinal indications), reviewing relevant randomised controlled trials. Recommendations are provided regarding special areas (including compassionate FMT use), and considerations regarding the evolving landscape of FMT and microbiome therapeutics.

The use of faecal microbiota transplant as treatment for recurrent or refractory Clostridioides difficile infection and other potential indications: second edition of joint British Society of Gastroenterology (BSG) and Healthcare Infection Society (HIS) guidelines.

The first British Society of Gastroenterology (BSG) and Healthcare Infection Society (HIS)-endorsed faecal microbiota transplant (FMT) guidelines were published in 2018. Over the past 5 years, there has been considerable growth in the evidence base (including publication of outcomes from large national FMT registries), necessitating an updated critical review of the literature and a second edition of the BSG/HIS FMT guidelines. These have been produced in accordance with National Institute for Health and Care Excellence-accredited methodology, thus have particular relevance for UK-based clinicians, but are intended to be of pertinence internationally. This second edition of the guidelines have been divided into recommendations, good practice points and recommendations against certain practices. With respect to FMT for Clostridioides difficile infection (CDI), key focus areas centred around timing of administration, increasing clinical experience of encapsulated FMT preparations and optimising donor screening. The latter topic is of particular relevance given the COVID-19 pandemic, and cases of patient morbidity and mortality resulting from FMT-related pathogen transmission. The guidelines also considered emergent literature on the use of FMT in non-CDI settings (including both gastrointestinal and non-gastrointestinal indications), reviewing relevant randomised controlled trials. Recommendations are provided regarding special areas (including compassionate FMT use), and considerations regarding the evolving landscape of FMT and microbiome therapeutics.

Altered circular RNA expressions in extracellular vesicles from bronchoalveolar lavage fluids in mice after bacterial infections.

Circular RNAs (circRNAs) are a class of transcripts that often are generated by back-splicing that covalently connects the 3'end of the exon to the 5'end. CircRNAs are more resistant to nuclease and more stable than their linear counterparts. One of the well-recognized roles of circRNAs is the miRNA sponging effects that potentially lead to the regulation of downstream proteins. Despite that circRNAs have been reported to be involved in a wide range of human diseases, including cancers, cardiovascular, and neurological diseases, they have not been studied in inflammatory lung responses. Here, we analyzed the circRNA profiles detected in extracellular vesicles (EVs) obtained from the broncho-alveolar lavage fluids (BALF) in response to LPS or acid instillation in mice. Next, we validated two specific circRNAs in the BALF-EVs and BALF cells in response to endotoxin by RT-qPCR, using specific primers targeting the circular form of RNAs rather than the linear host RNAs. The expression of these selected circRNAs in the BALF inflammatory cells, alveolar macrophages (AMs), neutrophils, and lung tissue were analyzed. We further predicted the potential miRNAs that interact with these circRNAs. Our study is the first report to show that circRNAs are detectable in BALF EVs obtained from mice. The EV-cargo circRNAs are significantly altered by the noxious stimuli. The circRNAs identified using microarrays may be validated by RT-qPCR using primers specific to the circular but not the linear form. Future studies to investigate circRNA expression and function including miRNA sponging in lung inflammation potentially uncover novel strategies to develop diagnostic/therapeutic targets.

Customized Lanthanide Nanobiohybrids for Noninvasive Precise Phototheranostics of Pulmonary Biofilm Infection.

A noninvasive strategy for in situ diagnosis and precise treatment of bacterial biofilm infections is highly anticipated but still a great challenge. Currently, no in vivo biofilm-targeted theranostic agent is available. Herein, we fabricated intelligent theranostic alginate lyase (Aly)-NaNdF4 nanohybrids with a 220 nm sunflower-like structure (NaNdF4@DMS-Aly) through an enrichment-encapsulating strategy, which exhibited excellent photothermal conversion efficiency and the second near-infrared (NIR-II) luminescence. Benefiting from the site-specific targeting and biofilm-responsive Aly release from NaNdF4@DMS-Aly, we not only enabled noninvasive diagnosis but also realized Aly-photothermal synergistic therapy and real-time evaluation of therapeutic effect in mice models with Pseudomonas aeruginosa biofilm-induced pulmonary infection. Furthermore, such nanobiohybrids with a sheddable siliceous shell are capable of delaying the NaNdF4 dissolution and biodegradation upon accomplishing the therapy, which is highly beneficial for the biosafety of theranostic agents.

Lung mucosal immunity to NTHi vaccine antigens: Antibodies in sputum of chronic obstructive pulmonary disease patients.

Chronic obstructive pulmonary disease (COPD) is a common chronic respiratory illness in older adults. A major cause of COPD-related morbidity and mortality is acute exacerbation of COPD (AECOPD). Bacteria in the lungs play a role in exacerbation development, and the most common pathogen is non-typeable Haemophilus influenzae (NTHi). A vaccine to prevent AECOPD containing NTHi surface antigens was tested in a clinical trial. This study measured IgG and IgA against NTHi vaccine antigens in sputum. Sputum samples from 40 COPD patients vaccinated with the NTHi vaccine were collected at baseline and 30 days after the second dose. IgG and IgA antibodies against the target antigens and albumin were analyzed in the sputum. We compared antibody signals before and after vaccination, analyzed correlation with disease severity and between sputum and serum samples, and assessed transudation. Antigen-specific IgG were absent before vaccination and present with high titers after vaccination. Antigen-specific IgA before and after vaccination were low but significantly different for two antigens. IgG correlated between sputum and serum, and between sputum and disease severity. Sputum albumin was higher in patients with severe COPD than in those with moderate COPD, suggesting changes in transudation played a role. We demonstrated that immunization with the NTHi vaccine induces antigen-specific antibodies in sputum. The correlation between IgG from sputum and serum and the presence of albumin in the sputum of severe COPD patients suggested transudation of antibodies from the serum to the lungs, although local IgG production could not be excluded.Clinical Trial Registration: NCT02075541.

What is the context? Chronic obstructive pulmonary disease (COPD) is the most common chronic respiratory illness in older adults and the third leading cause of death worldwide.One bacterium in the lungs, non-typeable Haemophilus influenzae (NTHi), is responsible for acute exacerbation of the disease, characterized by an increase in airway wall inflammation and symptoms, leading to high morbidity and mortality.A vaccine targeting NTHi was previously developed but did not show efficacy in reducing exacerbations in COPD patients, probably because the vaccine did not elicit an immune response in the lung mucosae, where the bacteria are located.What is the impact? Parenteral immunization with new vaccines targeting NTHi is able to elicit immune defense at the level of lung mucosae.Now that antibodies can be measured in sputum, new vaccines against COPD exacerbations or other lung infections can be tested for efficacy in the actual target tissue.Also, lung immunity against specific pathogens can now be tested.What is new? We determined that antigen-specific antibodies were present in the lungs after vaccination; these were assessed in sputum after vaccination with NTHi surface antigens.NTHi-specific IgG were present in the lungs and appeared to have arrived there primarily by transudation, a type of leakage from the serum to the lung mucosae.Transudation appeared to be stronger in severe than in moderate COPD patients.

Adhesin domains responsible for binding bacteria to surfaces they colonize project outwards from companion split domains.

Bacterial adhesins attach their hosts to surfaces that the bacteria will colonize. This surface adhesion occurs through specific ligand-binding domains located towards the distal end of the long adhesin molecules. However, recognizing which of the many adhesin domains are structural and which are ligand binding has been difficult up to now. Here we have used the protein structure modeling program AlphaFold2 to predict structures for these giant 0.2- to 1.5-megadalton proteins. Crystal structures previously solved for several adhesin regions are in good agreement with the models. Whereas most adhesin domains are linked in a linear fashion through their N- and C-terminal ends, ligand-binding domains can be recognized by budding out from a companion core domain so that their ligand-binding sites are projected away from the axis of the adhesin for maximal exposure to their targets. These companion domains are "split" in their continuity by projecting the ligand-binding domain outwards. The "split domains" are mostly ß-sandwich extender modules, but other domains like a ß-solenoid can serve the same function. Bioinformatic analyses of Gram-negative bacterial sequences revealed wide variety ligand-binding domains are used in their Repeats-in-Toxin adhesins. The ligands for many of these domains have yet to be identified but known ligands include various cell-surface glycans, proteins, and even ice. Recognizing the ligands to which the adhesins bind could lead to ways of blocking colonization by bacterial pathogens. Engineering different ligand-binding domains into an adhesin has the potential to change the surfaces to which bacteria bind.

Characteristics and Related Factors of Bacterial Infection Among Patients With Cirrhosis.

Background: Infection causes cirrhosis to decompensate, affecting liver function and resulting in several complications, including esophageal variceal hemorrhage, hepatic encephalopathy, and hepatorenal syndrome. Objective: This study aimed to identify the prevalence, essential features, and related factors of bacterial infection among patients with cirrhosis in Vietnam. Methods: This retrospective study included 317 patients diagnosed with cirrhosis, who were divided into two groups: group 1 including 125 patients with bacterial infection and group 2 including 192 patients without bacterial infection. Infection was diagnosed on the basis of its localization. Results: Spontaneous bacterial peritonitis (SBP; 31.2%) and pneumonia (28.8%) were the most common infections identified. The procalcitonin (PCT) level had a strong diagnostic value with an area under the curve value of 0.868. The most common type of gram-negative bacteria was Escherichia coli, while the gram-positive bacteria seen were Staphylococcus, Enterococcus, and Streptococcus among the patients with infection. In the logistic regression analysis, Child-Pugh class B and C (p<0.001, OR=4.14, CI=1.90-9.03; OR=4.76, CI=2.03-11.16, respectively) and the presence of acute kidney injury (p=0.009, OR=2.57, CI=1.27-5.22) and gastrointestinal hemorrhage (p=0.035, OR=0.39, CI=0.16-0.94) significantly differed between the groups. Conclusion: The most prevalent type of bacterial infection in patients with cirrhosis is SBP, with gram-negative bacteria being the most common cause. The PCT level is useful in identifying infection in patients with cirrhosis. Decompensated cirrhosis is linked to a higher risk of infection.