Exacerbated lung inflammation in offspring with high maternal antibody levels following secondary RSV exposure

Respiratory syncytial virus (RSV) is the primary cause of bronchiolitis-related hospitalizations among children under 5 years of age, with reinfection being common throughout life. Maternal vaccination has emerged as a promising strategy, delivering elevated antibody levels to newborns for immediate protection. However, limited research has explored the protective efficacy of maternal antibodies (matAbs) against secondary RSV infections in offspring. To address this gap, we employed a mouse model of maternal RSV vaccination and secondary infection of offspring to evaluate lung pathology following RSV reinfection in mice with varying levels of maternal antibody (matAb). Additionally, we aimed to investigate the potential causes of exacerbated lung inflammation in offspring with high matAb levels following secondary RSV exposure. Our findings revealed that offspring with elevated levels of maternal pre-F antibody demonstrated effective protection against lung pathology following the initial RSV infection. However, this protection was compromised upon reinfection, manifesting as heightened weight loss, exacerbated lung pathology, increased expression of RSV-A N genes, eosinophilia, enhanced IL-5, IL-13, MUC5AC, and eosinophils Major Basic Protein (MBP) production in lung tissue compared to offspring lacking matAbs. Importantly, these unexpected outcomes were not attributed to antibody-dependent enhancement (ADE) resulting from declining matAb levels over time. Notably, our findings showed a decline in secretory IgA (sIgA), mucosal IgA, and mucosal IgG levels in offspring with high matAb levels post-primary RSV challenge. We propose that this decline may be a critical factor contributing to the ineffective protection observed during secondary RSV exposure. Overall, these findings offer valuable insights into maternal vaccination against RSV, contributing to a comprehensive understanding and mitigation of potential risks associated with maternal RSV vaccination.

Patterns of antibiotic administration in Chinese neonates: results from a multi-center, point prevalence survey

OBJECTIVES

In this study, we describe the patterns of antibiotic prescription for neonates based on World Health Organization's (WHO) Essential Medicines List Access, Watch, and Reserve (AWaRe), and the Management of Antibiotic Classification (MAC) Guidelines in China.

METHODS

One-day point-prevalence surveys (PPS) on antimicrobial prescriptions were conducted on behalf of hospitalized neonates in China from September 1 and November 30, annually from 2017 to 2019.

RESULTS

Data was collected for a total of 2674 neonatal patients from 15 hospitals in 9 provinces across China of which 1520 were newborns who received at least one antibiotic agent. A total of 1943 antibiotic prescriptions were included in the analysis. The most commonly prescribed antibiotic was meropenem (11.8%). The most common reason for prescribing antibiotic to neonates was pneumonia (44.2%). There were 419 (21.6%), 1343 (69.1%) and 6 (0.3%) antibiotic prescriptions in the Access, Watch and Reserve groups, respectively. According to MAC Guidelines in China, there were 1090 (56.1%) antibiotic agents in the Restricted and 414 (21.3%) in the Special group.

CONCLUSION

Broad-spectrum antibiotics included in the Watch and Special groups were likely to be overused in Chinese neonates.

Panax notoginseng saponin R1 improves glucocorticoid-inhibited airway epithelium repair via glucocorticoid receptor β

BACKGROUND

Panax notoginseng saponin R1(PNS-R1), derived from Panax notoginseng roots, promotes wound repair, whereas glucocorticoids can inhibit the repair of airway epithelial damage in asthma.

OBJECTIVE

This study investigated whether PNS-R1 counteracts the inhibitory effects of glucocorticoids on the repair of airway epithelial damage in asthma.

METHODS

In vivo, female C57BL/6 mice were sensitized, challenged with house dust mites (HDM), and treated with dexamethasone, PNS-R1, and/or adenovirus GRβ-shRNA. Airway epithelium damage was examined using pathological sections of the trachea and bronchi, markers of airway inflammation, epithelial cells in bronchoalveolar lavage fluid, and expression of the E-cadherin protein. In vitro, we treated 16HBE cells with dexamethasone, PNS-R1, and/or GRβ-siRNA and detected cell proliferation and migration. The expression of GRβ and key components of MKP-1 and Erk1/2 were detected by western blotting.

RESULTS

In vivo, PNS-R1 reduced airway inflammation, hyperresponsiveness, and mucus hypersecretion; the combination of PNS-R1 and dexamethasone promoted airway epithelial integrity and reduced cell detachment. In vitro, PNS-R1 alleviated the inhibition of bronchial epithelial cell growth, migration, and proliferation by dexamethasone; PNS-R1 promoted GRβ expression, inhibited MKP-1 protein expression, and activated MAPK signaling, thereby promoting airway epithelial cell proliferation and repair.

CONCLUSIONS

Panax notoginseng saponin R1 alleviated the inhibitory effect of dexamethasone on the repair of airway epithelial damage in asthmatic mice, likely by promoting the proliferation of airway epithelial cells by stimulating GRβ expression and activating the MAPK pathway.

The impact of probiotics on gut microbiota in the eradication of Helicobacter pylori infection: a systematic review

OBJECTIVE

The effect of probiotics supplementation on the gut microbiota in Helicobacter pylori (H. pylori) eradication therapy is controversial. Therefore, this review aimed to illustrate changes in the gut microbiota after standard eradication therapy with probiotics supplements.

MATERIALS AND METHODS

A computerized literature search in PubMed, Cochrane Library, Web of Science, and Embase database was performed up to February 1st, 2022, with English language restriction. The extracted outcomes were analyzed, including gut microbiota, adverse effects, and eradication rate.

RESULTS

13 studies reported data on 777 participants who were finally eligible for this systematic review. All of them are randomized controlled trials investigating the effect of H. pylori eradication with probiotics supplementation therapy on gut microbiota. Probiotics supplementation seems to play a positive role in restoring the gut microbiota during H. pylori eradication therapy. However, the changes in the gut microbiota are still controversial. The included studies had significant heterogeneity in the study population, diagnostic methods of H. pylori infection, and detection techniques of the gut microbiota and probiotics species.

CONCLUSIONS

The results provided a basis for the rational selection of probiotics in the H. pylori eradication process. Probiotic supplementation might keep the balance of gut microbiota and reduce the gastrointestinal adverse effects of antibiotics, but whether it could improve the eradication rate or not is a debatable point. Therefore, more research is needed to provide evidence.

Global research status and trends of bronchiectasis in children from 2003 to 2022: A 20-year bibliometric analysis

Background

This study aims to analyze the research hotspots, evolution, and developing trends in pediatric bronchiectasis over the past 20 years using bibliometric analysis and visualization tools to identify potential new research directions.

Methods

Publications related to bronchiectasis in children were retrieved from the Web of Science Core Collection (WoSCC) database from 2003 to 2022. Knowledge maps were performed through VOSviewer1.6.18 and CiteSpace6.1 R2.

Results

A total of 2,133 publications were searched, while only 1,351 original articles written in English between 2003 and 2022 were incorporated. After removing duplicates, we finally included 1,350 articles published by 6,593 authors from 1,865 institutions in 80 countries/regions in 384 different academic journals with an average citation frequency of 24.91 times. The number of publications shows an extremely obvious binomial growth trend. The majority of publications originated from the United States, Australia, and England. The institutes in Australia, especially Charles Darwin University, published the most articles associated with pediatric bronchiectasis. In addition, Pediatric Pulmonology was the most published journal. In terms of authors, Chang AB was the most productive author, while Gangell CL had the highest average citation frequency. The five keywords that have appeared most frequently during the last two decades were "children," "cystic fibrosis," "bronchiectasis," "ct," and "pulmonary-function." According to keyword analysis, early diagnosis and intervention and optimal long-term pediatric-specific management were the most concerned topics for researchers.

Conclusion

This bibliometric analysis indicates that bronchiectasis in children has drawn increasing attention in the last two decades as its recognition continues to rise, providing scholars in the field with significant information on current topical issues and research frontiers.

Epidemiological characteristics of respiratory viruses in hospitalized children during the COVID-19 pandemic in southwestern China

Background

Multinational studies have reported that the implementation of nonpharmaceutical interventions (NPIs) to control severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) transmission coincided with the decline of other respiratory viruses, such as influenza viruses and respiratory syncytial virus.

Objective

To investigate the prevalence of common respiratory viruses during the coronavirus disease 2019 (COVID-19) pandemic.

Methods

Respiratory specimens of children with lower respiratory tract infections (LRTIs) hospitalized at the Children's Hospital of Chongqing Medical University from January 1, 2018 to December 31, 2021 were collected. Seven common pathogens, including respiratory syncytial virus (RSV), adenovirus (ADV), influenza virus A and B (Flu A, Flu B), and parainfluenza virus types 1-3 (PIV1-3), were detected by a multiplex direct immunofluorescence assay (DFA). Demographic data and laboratory test results were analyzed.

Results

1) A total of 31,113 children with LRTIs were enrolled, including 8141 in 2018, 8681 in 2019, 6252 in 2020, and 8059 in 2021.The overall detection rates decreased in 2020 and 2021 (P < 0.001). The detection rates of RSV, ADV, Flu A, PIV-1, and PIV-3 decreased when NPIs were active from February to August 2020, with Flu A decreasing most predominantly, from 2.7% to 0.3% (P < 0.05). The detection rates of RSV and PIV-1 resurged and even surpassed the historical level of 2018-2019, while Flu A continued decreasing when NPIs were lifted (P < 0.05). 2) Seasonal patterns of Flu A completely disappeared in 2020 and 2021. The Flu B epidemic was observed until October 2021 after a long period of low detection in 2020. RSV decreased sharply after January 2020 and stayed in a nearly dormant state during the next seven months. Nevertheless, the detection rates of RSV were abnormally higher than 10% in the summer of 2021. PIV-3 decreased significantly after the COVID-19 pandemic; however, it atypically surged from August to November 2020.

Conclusion

The NPIs implemented during the COVID-19 pandemic affected the prevalence and seasonal patterns of certain viruses such as RSV, PIV-3, and influenza viruses. We recommend continuous surveillance of the epidemiological and evolutionary dynamics of multiple respiratory pathogens, especially when NPIs are no longer necessary.

Total arterial revascularization is associated with long-term survival benefit in coronary artery bypass grafting: systematic review with meta-analysis

Importance

Total arterial revascularization (TAR), the complete avoidance of saphenous vein grafting (SVG) in coronary artery bypass grafting (CABG), is advocated based on the superior conduit durability and resistance against atherosclerosis. However, the low adoption rate of TAR indicates a high level of controversy.

Objective

To compare long-term survival between TAR and conventional CABG involving SVG.

Data sources

A comprehensive literature search was conducted through digital databases including MEDLINE, Embase, and Cochrane Central Register of Controlled Trials from the inception to May 2021.

Study selection

The inclusion criteria were randomized clinical trials, or propensity-score balanced or multivariable-adjusted observational studies with a sample size of at least 100 patients in each arm, isolated CABG, comparing TAR (SVG=0) vs. non-TAR (SVG≥1), and inclusion of all-cause mortality.

Data extraction and synthesis

Two reviewers performed independent extraction following Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines. Pooled hazard ratios (HR) and 95% confidence intervals (CI) were estimated with random-effect and fixed-effect models using generic inverse variance weighting. Individual patient time-to-event data were reconstructed to create an overall Kaplan-Meier survival function for matched studies. Sensitivity analyses were performed according to the risk of bias, matching status, and source of HR.

Main outcomes and measures

The primary endpoint was all-cause mortality.

Results

A total of 23 studies (100,314 patients), all with a retrospective observational design, were identified. The weighted mean follow-up time was 8.8 years post-operatively. Total arterial revascularization was associated with greater freedom from all-cause mortality than non-TAR (HR, 0.77, 95% CI, 0.71 to 0.84, p&lt;0.001). There was evidence of low heterogeneity (I2=45%) across studies. Low publication bias was observed. Leave-one-out influence analysis and sensitivity analyses produced consistent results. Cochrane Collaboration signaling domains showed no critical risk of bias.

Conclusions and relevance

This meta-analysis found superior late survival associated with total arterial revascularization. Further randomized clinical trials are needed.

Funding Acknowledgement

Type of funding sources: None.

[Long-term outcomes of 328 patients with of autism spectrum disorder after fecal microbiota transplantation]

Objective: To evaluate the efficacy and safety of fecal microbiota transplantation (FMT) in the treatment of autism spectrum disorder (ASD). Methods: A longitudinal study was conducted. Clinical data from ASD patients with gastrointestinal symptoms and who underwent FMT in the Tenth People's Hospital affiliated to Tongji University or Jinling Hospital between May 2012 to May 2021 were retrospectively collected. Scores derived from the autism behavior checklist (ABC), the childhood autism rating scale (CARS), the Bristol stool form scale (BSFS), and the gastrointestinal symptom rating scale (GSRS) were analyzed at baseline and at the 1st, 3rd, 6th, 12th, 24th, 36th, 48th and 60th month after FMT. Records of any adverse reactions were collected. Generalized estimating equations were used for analysis of data on time points before and after FMT. Results: A total of 328 patients met the inclusion criteria for this study. Their mean age was 6.1±3.4 years old. The cohort included 271 boys and 57 girls. The percentage of patients remaining in the study for post-treatment follow-up at the 1st, 3rd, 12th, 24th, 36th, 48th and 60th month were as follows: 303 (92.4%), 284 (86.7%), 213 (64.9%), 190 (57.9%), 143 (43.6%), 79 (24.1%), 46 (14.0%), 31 (9.5%). After FMT, the average ABC score was significantly improved in the first 36 months and remained improved at the 48th month. However, the average score was not significantly different from baseline by the 60th month (1st-36th month, P<0.001; 48th month, P=0.008; 60th month, P=0.108). The average CARS score improved significantly during the first 48 months and remained improved at the 60th month (1st-48th month, P<0.001; 60th month, P=0.010). The average BSFS score was also significantly improved in the first 36 months (with an accompanying stool morphology that resembled type 4). This improvement was maintained at the 48th month. However, the average score was similar to baseline at the 60th month (1st-36th month, P<0.001; 48th month, P=0.008; 60th month, P=0.109). The average GSRS score was significantly improved during the first 24 months, but not afterwards (1st-24th month, P<0.001; 36th month, P=0.209; 48th month, P=0.996; 60th month, P=0.668). The adverse events recorded during treatment included abdominal distension in 21 cases (6.4%), nausea in 14 cases (4.3%), vomiting in 9 cases (2.7%), abdominal pain in 15 cases (4.6%), diarrhea in 18 cases (5.5%), fever in 13 cases (4.0%), and excitement in 24 cases (7.3%). All adverse reactions were mild to moderate and improved immediately after suspension of FMT or on treatment of symptoms. No serious adverse reactions occurred. Conclusion: FMT has satisfactory long-term efficacy and safety for the treatment of ASD with gastrointestinal symptoms.

Antimicrobial prescribing for children in China: data from point prevalence surveys in 18 tertiary centres in China in 2016-2017

OBJECTIVES

The reports on evaluating the classification of antibiotic agents prescribed for Chinese children by combining WHO's and China's administrative categories were rare. This study aimed to investigate the pattern of antimicrobial agents prescribing for Chinese children in 2016.

SETTINGS

18 tertiary centres from nine provinces located in northern, southern, eastern and western China.

PARTICIPANTS

The antimicrobial prescribing data from the children admitted in medical wards, surgical wards and intensive care units were collected and analysed. A total of 3680 antibiotic prescriptions for Chinese children were included in the analysis.

PRIMARY AND SECONDARY OUTCOME MEASURES

One-day point-prevalence surveys (PPSs) on antimicrobial prescribing were conducted among hospitalised children in China between 1 February 2016 and 28 February 2017. Five hospitals participated in the first PPS, 13 hospitals in the second PPS, 17 hospitals in the third PPS and 18 hospitals in the fourth PPS. Patterns of antibiotic use with a drug utilisation of 90%, Anatomical Therapeutical Chemical Classification, WHO Access, Watch and Reserve (AWaRe) (version 2019) and antibiotic classification in China were described retrospectively.

RESULTS

A total of 4442 children and 3680 antibiotic prescriptions for Chinese children were included in the analysis. 2900 (65.3%) children received at least one ongoing antibiotic during the survey days. On the basis of WHO AWaRe classification, the proportion of antibiotics in the Watch group was 76.5% (2814/3680). According to the Management of Antibiotic Classification in China, 56.8% (2089/3680) and 16.1% (594/3680) of antibiotic prescriptions in the Restricted group and the Special group, respectively, were included into broad-spectrum antibiotics. The most common indication for antibiotics was bacterial lower respiratory tract infection (2044/3680, 55.5%).

CONCLUSIONS

The use of broad-spectrum antibiotics was frequent and excessive in hospitalised children in China in 2016.

Pharmacological inhibition of eIF2alpha phosphorylation by integrated stress response inhibitor (ISRIB) ameliorates vascular calcification in rats

Vascular calcification (VC) is an independent risk factor for cardiovascular events and all-cause mortality with the absence of current treatment. This study aimed to investigate whether eIF2alpha phosphorylation inhibition could ameliorate VC. VC in rats was induced by administration of vitamin D3 (3×10(5) IU/kg, intramuscularly) plus nicotine (25 mg/kg, intragastrically). ISRIB (0.25 mg/kg·week), an inhibitor of eIF2alpha phosphorylation, ameliorated the elevation of calcium deposition and ALP activity in calcified rat aortas, accompanied by amelioration of increased SBP, PP, and PWV. The decreased protein levels of calponin and SM22alpha, and the increased levels of RUNX2 and BMP2 in calcified aorta were all rescued by ISRIB, while the increased levels of the GRP78, GRP94, and C/EBP homologous proteins in rats with VC were also attenuated. Moreover, ISRIB could prevent the elevation of eIF2alpha phosphorylation and ATF4, and partially inhibit PERK phosphorylation in the calcified aorta. These results suggested that an eIF2alpha phosphorylation inhibitor could ameliorate VC pathogenesis by blocking eIF2alpha/ATF4 signaling, which may provide a new target for VC prevention and treatment.

Clinical and genetic features of primary ciliary dyskinesia in a cohort of consecutive clinically suspect children in western China

BACKGROUND

Primary ciliary dyskinesia (PCD) is a rare, inherited disorder of the motile cilia that exhibits genetic and clinical heterogeneity among different populations. PCD diagnosis remains challenging owing to the heterogeneity of associated clinical features and lack of a gold standard diagnostic test.

OBJECTIVE

The aim of this study was to analyze the clinical and genetic characteristics of a group of children with clinically suspected PCD in one region of China, with the goal of providing a more robust knowledge base regarding the genetic stratification underlying this disease in Chinese populations.

METHODS

We retrospectively analyzed the data from 38 patients with clinically suspected PCD who had undergone next-generation sequencing (NGS) between November 2016 and March 2021 in the respiratory department of a tertiary Children's hospital in Western China. The genetic features of the confirmed cases were summarized by reviewing data associated with other cohorts of Chinese children.

RESULTS

Overall, 16 patients were ultimately diagnosed with PCD with a median age of 8.5 years. All patients presented with a chronic wet cough, 93.75% exhibited chronic or recurrent sinusitis/rhinitis, 43.75% experienced recurrent wheezing, 56.25% reported respiratory symptoms present since infancy, 31.25% had a history of neonatal respiratory distress (NRD), and 25% exhibited otitis media. Only 18.75% of these patients exhibited laterality defects. High frequencies of DNAH11 mutations were detected by integrating data from PCD patient cohorts in China.

CONCLUSION

The high frequency of DNAH11 mutations may limit the utility of transmission electron microscopy (TEM) as a first-line approach to diagnosing PCD in China in the absence of other indicators.

Reassessing the role of tracheobronchomalacia in persistent wheezing

BACKGROUND

Tracheobronchomalacia (TBM) is often manifested as wheezing. Reassessing the role of TBM in persistent wheezing in children is essential.

METHODS

We selected children who were diagnosed with TBM by bronchoscopy and who underwent bronchoscopic reexamination for persistent wheezing or chronic cough between January 2009 and July 2019. The clinical and bronchoscopy data were collected and retrospectively reviewed. For statistical analysis, we used the Kaplan-Meier method, Kruskal-Wallis test, and Fisher exact test.

RESULTS

A total of 79 patients (57 males and 22 females) were included. The median age of the first TBM diagnosis was 7 (interquartile [IQR] 4-11) months. The median age of the first wheezing episode was 4 (IQR 3-7) months. During the time interval between the two bronchoscopies, malacia lesions resolved in 50 patients (63.3%), improvement was seen in 14 patients (17.7%), no change was observed in 11 patients (13.9%), and the condition was aggravated in 4 patients (5.1%). The malacia lesions in 37 patients resolved before 2 years of age. Among the 50 resolved patients, 22 patients (44.0%) reported wheezing three times or more between bronchoscopy evaluations, and 13 of these 22 patients (59.1%) with atopy or family history of allergic diseases were ultimately diagnosed with bronchial asthma.

CONCLUSIONS

In children with persistent wheezing, the role of TBM should be reassessed, especially in those with atopy or family history of allergic diseases, and bronchial asthma should be considered early.

ZEB1 recruit Brg1 to regulate airway remodeling epithelial-mesenchymal transition in asthma

What is the central question of this study? The aim was to investigate the function of Brg1 in airway remodeling epithelial-mesenchymal transition (EMT) of asthma and identify the transcription factor (TF) of Brg1 which bind to the protomer of E-cadherin. What is the main finding and its importance? This study highlighted an important molecular mechanism involving chromatin remodeling factor Brahma-related gene-1 (Brg1) that played a critical role in airway remodeling EMT of asthma and demonstrated ZEB1 was the key TF recruiting Brg1. This finding might offer new insights into gene-based therapy for asthma. ABSTRACT: Epithelial-mesenchymal transition (EMT) of airway remodeling happens in children with asthma. Reduction of epithelial marker E-cadherin is reported to be one of the initiating factors of EMT. Our previous study shows that chromatin remodeling factor Brahma-related gene-1 (Brg1) could regulate the expression of E-cadherin indirectly, but the transcription factor (TF) involved in the recruitment of Brg1 in asthma is unknown. Here, we studied the function of Brg1 in an ovalbumin (OVA)-induced asthma model (lung-specific conditional Brg1 (Brg1^-/- ) knockdown mice) and human bronchial epithelial 16HBE cells stably expressing Brg1 shRNA. Our results showed that Brg1 was involved in epithelial-mesenchymal transition in asthmatic mice by detecting the expression of EMT markers. Meanwhile, we identified that Brg1 participated in the TGF-β induced EMT of 16HBE cells. We observed that Zinc Finger E-Box Binding Homeobox 1 (ZEB1) and Brg1 colocalized in the EMT of TGF-β induced 16HBE cells. Further results revealed that ZEB1 recruited Brg1 and bound to the promoter region (+3563/3715) to regulate E-cadherin expression. Thus, ZEB1 might be the key TF to recruit Brg1 in airway remodeling EMT of asthma and might be a novel therapeutic target. This article is protected by copyright. All rights reserved.

Pattern of Antibiotic Prescriptions in Chinese Children, A Cross-Sectional Survey From 17 Hospitals Located Across 10 Provinces of China

Objectives

Use of Broad-spectrum antibiotics is related closely to increasing antimicrobial resistance. Reports on antibiotic prescriptions for Chinese children were rare. We described the prescribing patterns of antibiotic prescriptions for Chinese children from 2017 to 2019 based on the Anatomical Therapeutic Chemical Classification (ATC classification); the Access, Watch, and Reserve (AWaRe) classification from the World Health Organization (WHO), and the Management of Antibiotic Classification in China.

Methods

A 1-day point-prevalence survey (PPSs) on antibiotics prescribing for Chinese children was conducted in hospitalized children from 17 centers in 10 Chinese provinces from 1 September 2017 to 30 November 2019.

Results

A total of 4,982 antibiotic prescriptions for Chinese children were included in the analysis. There were 76 types of antibiotic agents in total, 22 (28.9%) of which accounted for 90% of all antibiotic prescriptions. The top-three antibiotics prescribed for children were azithromycin (684, 13.7%), ceftriaxone (508, 10.2%) and latamoxef (403, 8.1%). Third-generation cephalosporins (1,913, 38.4%) were the most commonly prescribed antibiotic classes. On the basis of the AWaRe classification, the Watch group antibiotics accounted for 76.3% and Access group antibiotics accounted for 12.1% of all antibiotic prescriptions. On the basis of the China classification, we showed that 26.5% of antibiotic prescriptions were in the Unrestricted group, 53.6% in the Restricted group, and 14.5% in the Special group.

Conclusion

The proportion of antibiotics included in the Watch group and the Special group was high in children in China. The AWaRe classification and China classification for antibiotic prescriptions could be used to supply detailed data for antibiotic stewardship as a simple metric.

Novel AVPR2 mutations and clinical characteristics in 28 Chinese families with congenital nephrogenic diabetes insipidus

AIMS

To investigate genotype and phenotype of congenital nephrogenic diabetes insipidus caused by AVPR2 mutations, which is rare and limitedly studied in Chinese population.

METHODS

88 subjects from 28 families with NDI in a department (Beijing, PUMCH) were screened for AVPR2 mutations. Medical records were retrospectively reviewed and characterized. Genotype and phenotype analysis was performed.

RESULTS

23 AVPR2 mutations were identified, including six novel mutations (p.Y117D, p.W208R, p.L313R, p.S127del, p.V162Sfs*30 and p.G251Pfs*96). The onset-age ranged from 1 week to 3 years. Common presentations were polydipsia and polyuria (100%) and intermittent fever (57%). 21% and 14% of patients had short stature and mental impairment. Urine SG and osmolality were decreased, while serum osmolality and sodium were high. Urological ultrasonography results showed hydronephrosis of the kidney (52%), dilation of the ureter (48%), and thickened bladder wall or increased residual urine (32%), led to intermittent urethral catheterization (7%), cystostomy (11%) and binary nephrostomy (4%). Urological defects were developed in older patients. Genotype and phenotype analysis revealed patients with non-missense mutations had higher levels of serum sodium than missense mutations.

CONCLUSION

In the first and largest case series of NDI caused by AVPR2 mutations in Chinese population, we established genetic profile and characterized clinical data, reporting six novel mutations. Further, we found genotype was associated with phenotype. This knowledge broadens genotype and phenotype spectrum of rare congenital NDI caused by AVPR2 mutations, and provides basis for studying molecular biology of AVPR2.

Manganese promoted wheat straw decomposition by regulating microbial communities and enzyme activities

AIMS

This study investigated the dose-effect of manganese (Mn) addition on wheat straw (WS) decomposition, and explored the potential mechanisms of Mn involved in the acceleration of WS decomposition in regards to the soil microbial communities and enzyme activities.

METHODS AND RESULTS

A 180-day incubation experiment was performed to examine the decomposition of WS under four Mn levels, that is, 0, 0.25, 1 and 2 mg g^-1 . The effects of microbial communities and enzyme activities were evaluated using control (0 mg g^-1 ) and Mn (0.25 mg g^-1 ) treatments. Our results revealed that Mn (0.25 mg g^-1 ) addition significantly increased WS decomposition, and enhanced the release of carbon and nitrogen. Optimal Mn addition (0.25 mg g^-1 ) also caused significant increases in the activity of neutral xylanase (NEX), laccase (Lac), manganese peroxidase (MnP) and lignin peroxidase (LiP) within the incubation period. Mn (0.25 mg g^-1 ) addition also enriched some operational taxonomic units (OTUs) that, in turn, had the potential ability to decompose crop straw, such as secreting lignocellulolytic enzymes.

CONCLUSIONS

Mn (0.25 mg g^-1 ) could promote WS decomposition through enrichment of the microbial species involved in biomass decomposition, which enhanced the lignocellulose-degrading enzyme activity.

SIGNIFICANCE AND IMPACT OF THE STUDY

This study provides evidence for Mn to promote WS biodegradation after Mn application, opening new windows to improve the utilization efficiency of crop residues.

GITRL on dendritic cells aggravates house dust mite-induced airway inflammation and airway hyperresponsiveness by modulating CD4+ T cell differentiation

Background

Glucocorticoid-induced tumor necrosis factor receptor family-related protein ligand (GITRL) plays an important role in tumors, autoimmunity and inflammation. However, GITRL is not known to modulate the pathogenesis of allergic asthma. In this study, we investigated whether regulating GITRL expressed on dendritic cells (DCs) can prevent asthma and to elucidate its mechanism of action.

Methods

In vivo, the role of GITRL in modulating house dust mite (HDM)-induced asthma was assessed in adeno-associated virus (AAV)-shGITRL mice. In vitro, the role of GITRL expression by DCs was evaluated in LV-shGITRL bone marrow dendritic cells (BMDCs) under HDM stimulation. And the direct effect of GITRL was observed by stimulating splenocytes with GITRL protein. The effect of regulating GITRL on CD4⁺ T cell differentiation was detected. Further, GITRL mRNA in the peripheral blood of asthmatic children was tested.

Results

GITRL was significantly increased in HDM-challenged mice. In GITRL knockdown mice, allergen-induced airway inflammation, serum total IgE levels and airway hyperresponsiveness (AHR) were reduced. In vitro, GITRL expression on BMDCs was increased after HDM stimulation. Further, knocking down GITRL on DCs partially restored the balance of Th1/Th2 and Th17/Treg cells. Moreover, GITRL stimulation in vitro inhibited Treg cell differentiation and promoted Th2 and Th17 cell differentiation. Similarly, GITRL mRNA expression was increased in the peripheral blood from asthmatic children.

Conclusions

This study identified a novel role for GITRL expressed by DCs as a positive regulator of CD4⁺ T cells responses in asthma, which implicates that GITRL inhibitors may be a potential immunotherapy for asthma.

Grynfeltt hernia repair using a Kugel patch

PURPOSE

To introduce a surgical technique for repairing Grynfeltt hernia using a Bard Kugel patch mesh.

METHOD

After incision and dissection, hernia was found behind the latissimus dorsi muscle. The retroperitoneal fat or sac was isolated from surrounding tissues and the retro muscular preperitoneal space was developed using blunt dissection at least 5 cm beyond the margins of defect in all directions. A proper size Kugel patch was placed into the place at least 3 cm beyond the muscular or rib edges. The defect was reduced and the mesh was fixed by interrupted sutures. Then the fibers of the latissimus dorsi muscle were reapproximated by loose absorbable suture. The skin was closed by continuous absorbable suture without any drainage.

RESULTS

The patients had a mean hospital stay of 3.22 days. The follow-up ranged from 4 months to 2 years and there were no recurrences or any other significant postoperative complications.

CONCLUSION

Repairing Grynfeltt hernias using a Kugel patch can be successfully performed with the posterior approach. This method of repair is easy, safe, and effective.

Human Umbilical Cord Mesenchymal Stem Cell-Derived Small Extracellular Vesicles Alleviate Lung Injury in Rat Model of Bronchopulmonary Dysplasia by Affecting Cell Survival and Angiogenesis

Bronchopulmonary dysplasia (BPD) is a serious chronic lung disease in premature newborns, with high morbidity and mortality rates. Mesenchymal stem cell (MSC) transplantation has developed into a promising approach to alleviate BPD. Small extracellular vesicles, which are an important therapeutic component of MSCs, have been reported to be effective in a mouse model of BPD. However, the affected cell types and detailed underlying mechanisms are unclear. In this study, we found that human umbilical cord mesenchymal stem cell-derived small extracellular vesicles (hucMSC-sEVs) were successfully absorbed by lung tissue after intratracheal administration, and remained in the lungs for at least 72 h. The results showed that hucMSC-sEVs restored alveolar structure and lung function, and ameliorated pulmonary hypertension in a rat model of BPD. The number of Ki-67-positive lung cells were improved, while the number of TUNEL-positive lung cells were reduced in our hucMSC-sEV-treated BPD model. Additionally, SP-C staining (a marker of type II alveolar epithelial cells, TIIAECs) and CD31 staining (a marker of pulmonary vascular endothelial cells, PVECs) were both increased in a hyperoxia-induced BPD model treated with hucMSC-sEVs. In vitro, under hyperoxic conditions, the tube-like structure formation was improved in human umbilical vein endothelial cells, and the proliferation was increased and the apoptosis was attenuated in MLE-12 cells treated with hucMSC-sEVs. Furthermore, we observed downregulated expression of PTEN and cleaved-caspase3, and upregulated expression of p-Akt and vascular endothelial growth factor-A in our hucMSC-sEV-treated BPD model. In conclusion, hucMSC-sEVs improved alveolarization and angiogenesis in a rat BPD model by protecting TIIAECs and PVECs, which were associated with the PTEN/Akt signaling pathway.

Low-Dose LPS Induces Tolerogenic Treg Skewing in Asthma

The mechanism(s) underlying endotoxin tolerance in asthma remain elusive. As the endotoxin lipopolysaccharide (LPS) affects the expression of the regulatory T-cell (Treg)-suppressive glucocorticoid-induced tumor necrosis factor receptor ligand (GITRL) on antigen-presenting dendritic cells (DCs), we hypothesized that LPS-induced changes in DC GITRL expression may impact Treg-mediated T-helper (Th) cell suppression and the induction of endotoxin tolerance. Here, we propose a novel mechanism by which low-dose LPS inhalation in neonatal mice induces endotoxin tolerance, thereby offering protection from later asthma development. Three-day old wild-type and Toll-like receptor 4 (TLR4)-deficient neonatal mice were exposed to low-dose LPS (1 μg) intranasally for 10 consecutive days prior to ovalbumin (OVA)-induced asthma to better understand the tolerogenic mechanism(s) of low-dose LPS pre-exposure. In vivo findings were validated using in vitro co-culturing studies of primary CD11c⁺ DCs and CD4⁺ T-cells with or without low-dose LPS pre-exposure before OVA stimulation. Low-dose LPS pre-exposure upregulated the Treg response and downregulated pathogenic Th2 and Th17 responses through promoting apoptosis of Th2 and Th17 cells. Low-dose LPS pre-exposure downregulated DC GITRL expression and T-cell GITR expression. Artificial DC GITRL expression abrogated the tolerogenic Treg-skewing effect of low-dose LPS pre-exposure. Low-dose LPS pre-exposure inhibited TRIF/IRF3/IFNβ signaling and upregulated expression of tolerogenic TRIF/IRF3/IFNβ negative regulators in a TLR4-dependent manner. This tolerogenic DC GITRL downregulation was attributable to TRIF/IRF3/IFNβ signaling inhibition. Low-dose LPS pre-exposure produces tolerogenic Treg skewing in neonatal asthmatic mice, a phenomenon attributable to TLR4-dependent TRIF/IRF3/IFNβ-mediated DC GITRL downregulation.