M2 macrophages participate in ILC2 activation induced by Helicobacter pylori infection.

Helicobacter pylori (H. pylori) causes a diversity of gastric diseases. The host immune response evoked by H. pylori infection is complicated and can influence the development and progression of diseases. We have reported that the Group 2 innate lymphocytes (ILC2) were promoted and took part in building type-2 immunity in H. pylori infection-related gastric diseases. Therefore, in the present study, we aim to clarify how H. pylori infection induces the activation of ILC2. It was found that macrophages were necessary for activating ILC2 in H. pylori infection. Mechanistically, H. pylori infection up-regulated the expression of indoleamine 2,3-dioxygenase (IDO) in macrophages to induce M2 polarization, and the latter secreted the alarmin cytokine Thymic Stromal Lymphopoietin (TSLP) to arouse ILC2.

Ling-Gui-Zhu-Gan decoction ameliorates nonalcoholic fatty liver disease via modulating the gut microbiota.

Numerous studies have supported that nonalcoholic fatty liver disease (NAFLD) is highly associated with gut microbiota dysbiosis. Ling-Gui-Zhu-Gan decoction (LG) has been clinically used to treat NAFLD, but the underlying mechanism remains unknown. This study investigated the therapeutic effect and mechanisms of LG in mice with NAFLD induced by a high-fat diet (HD). An HD-induced NAFLD mice model was established to evaluate the efficacy of LG followed by biochemical and histopathological analysis. Metagenomics, metabolomics, and transcriptomics were used to explore the structure and metabolism of the gut microbiota. LG significantly improved hepatic function and decreased lipid droplet accumulation in HD-induced NAFLD mice. LG reversed the structure of the gut microbiota that is damaged by HD and improved intestinal barrier function. Meanwhile, the LG group showed a lower total blood bile acids (BAs) concentration, a shifted BAs composition, and a higher fecal short-chain fatty acids (SCFAs) concentration. Furthermore, LG could regulate the hepatic expression of genes associated with the primary BAs biosynthesis pathway and peroxisome proliferator-activated receptor (PPAR) signaling pathway. Our study suggested that LG could ameliorate NAFLD by altering the structure and metabolism of gut microbiota, while BAs and SCFAs are considered possible mediating substances. IMPORTANCE: Until now, there has still been no study on the gut microbiota and metabolomics of Ling-Gui-Zhu-Gan decoction (LG) in nonalcoholic fatty liver disease (NAFLD) mouse models. Our study is the first to report on the reshaping of the structure and metabolism of the gut microbiota by LG, as well as explore the potential mechanism underlying the improvement of NAFLD. Specifically, our study demonstrates the potential of gut microbial-derived short-chain fatty acids (SCFAs) and blood bile acids (BAs) as mediators of LG therapy for NAFLD in animal models. Based on the results of transcriptomics, we further verified that LG attenuates NAFLD by restoring the metabolic disorder of BAs via the up-regulation of Fgf15/FXR in the ileum and down-regulation of CYP7A1/FXR in the liver. LG also reduces lipogenesis in NAFLD mice by mediating the peroxisome proliferator-activated receptor (PPAR) signaling pathway, which then contributes to reducing hepatic inflammation and improving intestinal barrier function to treat NAFLD.

Unveiling the functional diversity of ionotropic glutamate receptors in the Pacific oyster (Crassostrea gigas) by systematic studies.

Ionotropic glutamate receptors (iGluRs), pivotal in mediating excitatory neurosignals within the central nervous system, are instrumental in environmental stress responses. In this investigation, 12 iGluRs identified in the Pacific oyster are herein designated as CgiGluRs, and further categorized into three distinct subfamilies based on their transmembrane domains. Cross-species evolutionary analysis unveiled a high degree of conservation in the sequence and structural attributes of these CgiGluRs. These receptors are ubiquitously distributed across various tissues, with pronounced expression in the oyster's mantle, labial palps, and gills, underlining their integral role in the oyster's environmental sensing mechanisms. Post the D-shaped larval stage, a marked upward trend in CgiGluRs expression was observed, denoting their critical involvement in oyster development beyond this phase. Exposure to five metals-cadmium (Cd), copper (Cu), zinc (Zn), mercury (Hg), and lead (Pb)-elicited a significant upregulation of CgGRIA4 expression, indicating a robust response to metal stress. A KEGG enrichment analysis on 142 genes, exhibiting parallel expression trends with CgGRIA4 under metal stress, suggests that CgGRIA4 could augment excitatory signal transmission by activating glutamatergic and dopaminergic synapses, thereby contributing to the metal stress response in the oyster. This inquiry not only bolsters our comprehension of the iGluRs gene family in metal stress response but also paves the way for future exploration of its cardinal role in cellular signaling and environmental adaptability.

Microalgae-assisted heterotrophic nitrification-aerobic denitrification process for cost-effective nitrogen and phosphorus removal from high-salinity wastewater: Performance, mechanism, and bacterial community.

A microalgae-assisted heterotrophic nitrification-aerobic denitrification (HNAD) system for efficient nutrient removal from high-salinity wastewater was constructed for the first time as a cost-effective process in the present study. Excellent nutrient removal (∼100.0 %) was achieved through the symbiotic system. The biological removal process, biologically induced phosphate precipitation (BIPP), microalgae uptake, and ammonia stripping worked together for nutrient removal. Furthermore, the biological removal process achieved by biofilm contributed to approximately 55.3-71.8 % of nitrogen removal. BIPP undertook approximately 45.6-51.8 % of phosphorus removal. Batch activity tests confirmed that HNAD fulfilled an extremely critical role in nitrogen removal. Microalgal metabolism drove BIPP to achieve efficient phosphorus removal. Moreover, as the main HNAD bacteria, OLB13 and Thauera were enriched. The preliminary energy flow analysis demonstrated that the symbiotic system could achieve energy neutrality, theoretically. The findings provide novel insights into strategies of low-carbon and efficient nutrient removal from high-salinity wastewater.

Helicobacter pylori infection selectively attenuates endothelial function in male mice via exosomes-mediated ROS production.

Background: Substantial sex differences exist in atherosclerosis. Excessive reactive oxygen species (ROS) formation could lead to endothelial dysfunction which is critical to atherosclerosis development and progression. Helicobacter pylori (H. pylori) infection has been shown to attenuate endothelial function via exosomes-mediated ROS formation. We have demonstrated that H. pylori infection selectively increases atherosclerosis risk in males with unknown mechanism(s). The present study was to test the hypothesis that H. pylori infection impaired endothelial function selectively in male mice through exosome-mediated ROS formation. Methods and results: Age-matched male and female C57BL/6 mice were infected with CagA+ H. pylori to investigate sex differences in H. pylori infection-induced endothelial dysfunction. H. pylori infection attenuated acetylcholine (ACh)-induced endothelium-dependent aortic relaxation without changing nitroglycerine-induced endothelium-independent relaxation in male but not female mice, associated with increased ROS formation in aorta compared with controls, which could be reversed by N-acetylcysteine treatment. Treatment of cultured mouse brain microvascular endothelial cells with exosomes from H. pylori infected male, not female, mice significantly increased intracellular ROS production and impaired endothelial function with decreased migration, tube formation, and proliferation, which could be prevented with N-acetylcysteine treatment. Conclusions: H. pylori infection selectively impairs endothelial function in male mice due to exosome-mediated ROS formation.

Hydrogen sulfide alleviates beryllium sulfate-induced ferroptosis and ferritinophagy in 16HBE cells.

Beryllium sulfate (BeSO4 ) can result to lung injuries, such as leading to lipid peroxidation and autophagy, and the treatment of beryllium disease has not been well improved. Ferroptosis is a regulated cell death process driven by iron-dependent and lipid peroxidation, while ferritinophagy is a process mediated by nuclear receptor coactivator 4 (NCOA4), combined with ferritin heavy chain 1 (FTH1) degradation and release Fe2+ , which regulated intracellular iron metabolism and ferroptosis. Hydrogen sulfide (H2 S) has the effects of antioxidant, antiautophagy, and antiferroptosis. This study aimed to investigate the effect of H2 S on BeSO4 -induced ferroptosis and ferritinophagy in 16HBE cells and the underlying mechanism. In this study, BeSO4 -induced 16HBE cell injury model was established based on cellular level and pretreated with deferoxamine (DFO, a ferroptosis inhibitor), sodium hydrosulfide (NaHS, a H2 S donor), or NCOA4 siRNA and, subsequently, performed to detect the levels of lipid peroxidation and Fe2+ and the biomarkers of ferroptosis and ferritinophagy. More importantly, our research found that DFO, NaHS, or NCOA4 siRNA alleviated BeSO4 -induced ferroptosis and ferritinophagy by decreasing the accumulation of Fe2+ and lipid peroxides. Furthermore, the relationship between ferroptosis, ferritinophagy, H2 S, and beryllium disease is not well defined; therefore, our research is innovative. Overall, our results provided a new theoretical basis for the prevention and treatment of beryllium disease and suggested that the application of H2 S, blocking ferroptosis, and ferritinophagy may be a potential therapeutic direction for the prevention and treatment of beryllium disease.

Aerobic electrotrophic denitrification coupled with biologically induced phosphate precipitation for nitrogen and phosphorus removal from high-salinity wastewater: Performance, mechanism, and microbial community.

Electrotrophic denitrification (ED) is a promising nitrogen removal technique; however, the potential of ED coupled with biologically induced phosphate precipitation (BIPP) has not been fully explored. In this study, the performances, mechanisms, and microbial communities of the coupled system were investigated. The results showed that excellent nitrogen and phosphorus removal (both exceeding 92 %) was achieved in the salinity range of 20-60 g/L. ED contributed to approximately 83.4 % of nitrogen removal. BIPP removed approximately 63.5 % of the phosphorus. Batch activity tests confirmed that aerobic/anoxic bio-electrochemical and autotrophic/heterotrophic denitrification worked together for nitrate removal. Sulfate reduction had a negative impact on denitrification. Moreover, phosphorus removal was controlled by ED and calcium ions. The alkaline solution environment created by denitrification may greatly promote the formation of hydroxyapatite. Microbial community analyses indicated that the key bacteria involved in aerobic ED was Arcobacter. These findings will aid in the advanced treatment of high-salinity wastewater.

Corticotropin-releasing factor is involved in acute stress-induced analgesia and antipruritus.

BACKGROUND: Under the condition of stress, the hypothalamic-pituitary-adrenal axis (HPA axis) is activated and causes the secretion of corticotropin-releasing factor (CRF). Previous studies have demonstrated that CRF is involved in the regulation of pain and itch. Thus, it remains worthy to explore whether the desensitization of pain and itch under high-intensity acute stress (such as high fear and tension) is related to the sharp increase of CRF. METHODS: Forced swimming was used to simulate acute stress. ELISA and pharmacological methods were conducted to observe the effects of forced swimming on acute pain or itch and the relationship between blood CRF content and itch or pain behavior. Intracerebroventricular (ICV) administration of CRF was conducted to examine the effects of CRF on acute pain or itch. Intrathecal administration of CRF receptor agonist or antagonist was conducted to examine the receptor mechanisms of the regulatory role of CRF in pain and itch. RESULTS: ELISA experiment showed that the serum CRF in mice reached its peak within 5-10 min after acute stress (forced swimming). Behavioral data showed that the scratching behavior induced by itch agents decreased after acute swimming, while the mechanical pain threshold increased significantly. The inhibitory effect of acute stress on pain and itch is mediated by CRF receptor2 (CRFR2). Then, ICV injection of CRF was used to simulate the massive release of CRF under acute stress, and we observed that the scratching behavior induced by histamine or chloroquine was significantly inhibited after ICV injection of CRF. The above effects of CRF are mainly mediated by CRFR2. These results suggest that 5-10 min after acute stress, a large amount of CRF is released into the blood from the hypothalamus, which significantly inhibits acute pain and itch by acting on CRFR2. ICV injection of CRF can replicate the antipruritus effects of acute stress. CONCLUSIONS: The present study investigated the mechanism of acute stress-induced analgesia and antipruritus and provided theoretical support for the treatment of pain and itch.

Identification of a Five-mRNA Signature as a Novel Potential Prognostic Biomarker for Glioblastoma by Integrative Analysis.

Despite the availability of advanced multimodal therapy, the prognosis of patients suffering from glioblastoma (GBM) remains poor. We conducted a genome-wide integrative analysis of mRNA expression profiles in 302 GBM tissues and 209 normal brain tissues from the Gene Expression Omnibus (GEO), The Cancer Genome Atlas (TCGA), and the Genotype-Tissue Expression (GTEx) project to examine the prognostic and predictive value of specific mRNAs in GBM. A total of 26 mRNAs were identified to be closely related to GBM patients' OS (p < 0.05). Utilizing survival analysis and the Cox regression model, we discovered a set of five mRNAs (PTPRN, ABCC3, MDK, NMB, and RALYL) from these 26 mRNAs that displayed the capacity to stratify patients into high- and low-risk groups with statistically different overall survival in the training set. The model of the five-mRNA biomarker signature was successfully verified on a testing set and independent sets. Moreover, multivariate Cox regression analysis revealed that the five-mRNA biomarker signature was a prognostic factor for the survival of patients with GBM independent of clinical characteristics and molecular features (p < 0.05). Gene set enrichment analysis indicated that the five-mRNA biomarker signature might be implicated in the incidence and development of GBM through its roles in known cancer-related pathways, signaling molecules, and the immune system. Moreover, consistent with the bioinformatics analysis, NMB, ABCC3, and MDK mRNA expression was considerably higher in four human GBM cells, and the expression of PTPRN and RALYL was decreased in GBM cells (p < 0.05). Our study developed a novel candidate model that provides new prospective prognostic biomarkers for GBM.

N-Acetylcysteine Enhances the Recovery of Ischemic Limb in Type-2 Diabetic Mice.

Critical limb ischemia (CLI) is a severe complication of diabetes mellitus that occurs without effective therapy. Excessive reactive oxygen species (ROS) production and oxidative stress play critical roles in the development of diabetic cardiovascular complications. N-acetylcysteine (NAC) reduces ischemia-induced ROS production. The present study aimed to investigate the effect of NAC on the recovery of ischemic limb in an experimental model of type-2 diabetes. TALLYHO/JngJ diabetic and SWR/J non-diabetic mice were used for developing a CLI model. For NAC treatment, mice received NAC (1 mg/mL) in their drinking water for 24 h before initiating CLI, and continuously for the duration of the experiment. Blood flow, mechanical function, histology, expression of antioxidant enzymes including superoxide dismutase (SOD)-1, SOD-3, glutathione peroxidase (Gpx)-1, catalase, and phosphorylated insulin receptor substrate (IRS)-1, Akt, and eNOS in ischemic limb were evaluated in vivo or ex vivo. Body weight, blood glucose, plasma advanced glycation end-products (AGEs), plasma insulin, insulin resistance index, and plasma TNF-a were also evaluated during the experiment. NAC treatment effectively attenuated ROS production with preserved expressions of SOD-1, Gpx-1, catalase, phosphorylated Akt, and eNOS, and enhanced the recovery of blood flow and function of the diabetic ischemic limb. NAC treatment also significantly decreased the levels of phosphorylated IRS-1 (Ser307) expression and plasma TNF-α in diabetic mice without significant changes in blood glucose and AGEs levels. In conclusion, NAC treatment enhanced the recovery of blood flow and mechanical function in ischemic limbs in T2D mice in association with improved tissue redox/inflammatory status and insulin resistance.

CagA+ Helicobacter pylori, Not CagA- Helicobacter pylori, Infection Impairs Endothelial Function Through Exosomes-Mediated ROS Formation.

Background: Helicobacter pylori (H. pylori) infection increases the risk for atherosclerosis, and ROS are critical to endothelial dysfunction and atherosclerosis. CagA is a major H. pylori virulence factor associated with atherosclerosis. The present study aimed to test the hypothesis that CagA+ H. pylori effectively colonizes gastric mucosa, and CagA+ H. pylori, but not CagA- H. pylori, infection impairs endothelial function through exosomes-mediated ROS formation. Methods: C57BL/6 were used to determine the colonization ability of CagA+ H. pylori and CagA- H. pylori. ROS production, endothelial function of thoracic aorta and atherosclerosis were measured in CagA+ H. pylori and CagA- H. pylori infected mice. Exosomes from CagA+ H. pylori and CagA- H. pylori or without H. pylori infected mouse serum or GES-1 were isolated and co-cultured with bEND.3 and HUVECs to determine how CagA+ H. pylori infection impairs endothelial function. Further, GW4869 was used to determine if CagA+ H. pylori infection could lead to endothelial dysfunction and atherosclerosis through an exosomes-mediated mechanism. Results: CagA+ H. pylori colonized gastric mucosa more effectively than CagA- H. pylori in mice. CagA+ H. pylori, not CagA- H. pylori, infection significantly increased aortic ROS production, decreased ACh-induced aortic relaxation, and enhanced early atherosclerosis formation, which were prevented with N-acetylcysteine treatment. Treatment with CagA-containing exosomes significantly increased intracellular ROS production in endothelial cells and impaired their function. Inhibition of exosomes secretion with GW4869 effectively prevented excessive aortic ROS production, endothelial dysfunction, and atherosclerosis in mice with CagA+ H. pylori infection. Conclusion: These data suggest that CagA+ H. pylori effectively colonizes gastric mucosa, impairs endothelial function, and enhances atherosclerosis via exosomes-mediated ROS formation in mice.

Abdominal Aortic Endothelial Dysfunction Occurs in Female Mice With Dextran Sodium Sulfate-Induced Chronic Colitis Independently of Reactive Oxygen Species Formation.

Background and Objective: Inflammatory bowel disease (IBD) produces significant local and systemic inflammation with increased reactive oxygen species (ROS) formation. IBD Patients are at an increased risk for developing endothelial dysfunction and cardiovascular diseases. The present study tested the hypothesis that IBD impairs aortic endothelial function via ROS formation and investigate potential sex-related differences. Methods and Results: Acute and chronic colitis models were induced in male and female C57BL/6 mice with dextran sodium sulfate (DSS) treatment. Aortic wall stiffness, endothelial function, and ROS levels, as well as serum levels of pro-inflammatory cytokines were evaluated. Acetylcholine (Ach)-induced endothelium-dependent relaxation of abdominal aorta without perivascular adipose tissue (PVAT) was significantly reduced in female mice, not males, with chronic colitis without a change in nitroglycerin-induced endothelium-independent relaxation. PVAT effectively preserved Ach-induced relaxation in abdominal aorta of female mice with chronic colitis. Aortic peak velocity, maximal intraluminal diameters, pulse wave velocity, distensibility and radial strain were preserved in mice with both acute and chronic colitis. Although pro-inflammatory cytokines levels were increased in mice with acute and chronic colitis, aortic ROS levels were not increased. Conclusion: The data demonstrate that abdominal aortic endothelial function was attenuated selectively in female mice with chronic colitis independent of ROS formation. Further, PVAT played an important role in preserving endothelial function in female mice with chronic colitis.

Optimal Frequency for Changing Single-Use Enteral Delivery Sets in Infants after Congenital Heart Surgery: A Randomized Controlled Trial.

Objective We aimed to assess the optimal frequency for changing single-use enteral delivery sets during postoperative enteral feeding in infants with congenital heart disease (CHD).Methods We enrolled 120 CHD infants who were fed using an enteral nutrition pump directly connected to a milk bottle with a single-use enteral delivery set in a four-arm randomized controlled trial (ChiCTR2000039544). Patients were randomized into four groups based on the replacement frequency of the enteral delivery set (6 h, 12 h, 18 h, and 24 h groups). The primary outcome was the percentage of contaminated enteral delivery sets (overgrowth of microbiota and colonization of pathogenic bacteria). Secondary outcomes included evidence of infection, gastrointestinal tolerance, intestinal microflora dysbiosis, and healthcare costs.Results The percentages of microbial overgrowth detected in the 6 h, 12 h, 18 h, and 24 h groups were 6.7%, 30.0%, 46.7%, and 80%, respectively (P < 0.001). Significant differences were observed between the 6 h and 18 h groups (P < 0.001), the 6 h and 24 h groups (P < 0.001), and the 18 h and 24 h groups (P = 0.007). Meanwhile, pathogenic bacterial colonization was detected in 0, 4, 6, and 11 delivery sets in the 6 h, 12 h, 18 h, and 24 h groups, respectively (P = 0.002). No difference in clinical symptoms was found among the four groups. The total cost per patient in the 12 h group and the 18 h group was 340.2 RMB and 226.8 RMB, respectively.Conclusion Taking into consideration both microbial overgrowth and cost-effectiveness, the results of this study indicate that for children receiving continuous enteral feeding following CHD surgery, the optimal frequency for changing the single-use enteral delivery set when formula reconstituted from powder is used is 18 hours.

Explainable machine learning model for predicting the occurrence of postoperative malnutrition in children with congenital heart disease.

BACKGROUND & AIMS: Malnutrition is persistent in 50%-75% of children with congenital heart disease (CHD) after surgery, and early prediction is crucial for nutritional intervention. The aim of this study was to develop and validate machine learning (ML) models to predict the malnutrition status of children with CHD. We used explainable ML methods to provide insight into the model's predictions and outcomes. METHODS: This prospective cohort study included consecutive children with CHD admitted to the hospital from December 2017 to May 2020. The cohort data were divided into the training and test data sets based on the follow-up time. The outcome of the study was CHD child malnutrition 1 year after surgery, the primary outcome was an underweight status, and the secondary outcomes were stunted and wasting status. We used five ML algorithms with multiple features to construct prediction models, and the performance of these ML models was measured by an area under the receiver operating characteristic curve (AUC) analysis. We also used the permutation importance and SHapley Additive exPlanations (SHAP) to determine the importance of the selected features and interpret the ML models. RESULTS: We enrolled 536 children with CHD who underwent complete repair. The proportions of children with an underweight, stunted, or wasting status 1 year after surgery were 18.1% (97/536), 12.1% (65/536), and 17.5% (94/536), respectively. All patients contributed to the generation of 115 useable features, which allowed us to build models to predict malnutrition. Five prediction algorithms were used, and the XGBoost model achieved the greatest AUC in all outcomes. The results obtained from the permutation importance and SHAP analyses showed that the 1-month postoperative WAZ-score, discharge WAZ score and preoperative WAZ score were the top 3 important features in predicting an underweight status in the XGBoost algorithm. Regarding the stunted status, the top 3 important features were the 1-month postoperative HAZ score, discharge HAZ score, and aortic clamping time. Regarding the wasting status, the top 3 important features were the hospital length of stay, formula intake, and discharge WHZ-score. We also used a narrative case report as an example to describe the clinical manifestations and predicted the primary outcomes of two children. CONCLUSIONS: We developed an ML model (XGBoost) that provides accurate early predictions of malnutrition 1-year postoperatively in children with CHD. Because the ML model is explainable, it may better enable clinicians to better understand the reasoning underlying the outcome. Our study could aid in determining individual treatment and nutritional follow-up strategies for children with CHD.

Structural and Functional Modulation of Gut Microbiota by Jiangzhi Granules during the Amelioration of Nonalcoholic Fatty Liver Disease.

Recently, accumulating evidence revealed that nonalcoholic fatty liver disease (NAFLD) is highly associated with the dysbiosis of gut microbiota. Jiang Zhi Granule (JZG), which is composed of five widely used Chinese herbs, has shown hypolipidemic effect, while whether such effect is mediated by gut microbiota is still unclear. Here, we found that both low and high doses of JZG (LJZ and HJZ) could improve hepatic steatosis and function, as well as insulin resistance in NAFLD mice. 16S rRNA gene sequencing revealed that JZG treatment could reverse the dysbiosis of intestinal flora in NAFLD mice, exhibiting a dose-dependent effect. Notably, HJZ could significantly reduce the relative abundance of Desulfovibrionaceae, while increasing the relative abundance of such as S24_7 and Lachnospiraceae. PICRUSt analysis showed that HJZ could significantly alter the functional profile of gut microbiota, including the reduction of the lipopolysaccharide biosynthesis and sulfur metabolism pathway, which is verified by the decreased levels of fecal hydrogen sulfide (H2S) and serum lipopolysaccharide binding protein (LBP). In addition, hepatic mRNA sequencing further indicated that the HJZ group can regulate the peroxisome proliferator-activated receptor (PPAR) pathway and inflammatory signaling pathway, as validated by RT-PCR and Western blot. We also found that different doses of JZG may regulate lipid metabolism through differentiated pathways, as LJZ mainly through the promotion of hepatic lipid hydrolysis, while HJZ mainly through the improvement of hepatic lipid oxidation. Taken together, JZG could modulate gut dysbiosis with dose-effect, alleviate inflammation level, and regulate hepatic lipid metabolism, which may subsequently contribute to the improvement of NAFLD. Our study revealed the underlying mechanisms in the improvement of NAFLD by a Chinese herbal compound, providing future guidance for clinical usage.

Mutations in the regulatory regions result in increased streptomycin resistance and keratinase synthesis in Bacillus thuringiensis.

Keratinases are a group of proteases of great industrial significance. To take full advantage of Bacillus species as an inherent superior microbial producer of proteases, we performed the ribosome engineering to improve the keratinase synthesis capacity of the wild-type Bacillus thuringiensis by inducing streptomycin resistance. Mutant Bt(Str-O) was identified as a stable keratinase overproducer. Comparative characterization of the two strains revealed that, although the resistance to Streptomycin increased by eight-fold in MIC, the mutant's resistance to other commonly used antibiotics was not affected. Furthermore, the mutant exhibited an enhanced keratinase synthesis (1.5-fold) when cultured in a liquid LB medium. In the whole feather degradation experiment, the mutant could secret twofold keratinase into the medium, reaching 640 U/mL per 107 CFU. By contrast, no significant differences were found in the scanning electron microscopic analysis and spore formation experiment. To understand the genetic factors causing these phenotypic changes, we cloned and analyzed the rpsL gene. No mutation was observed. We subsequently determined the genome sequences of the two strains. Comparing the rpsL gene revealed that the emergence of streptomycin resistance was not necessarily dependent on the mutation(s) in the generally recognized "hotspot." Genome-wide analysis showed that the phenotypic changes of the mutant were the collective consequence of the genetic variations occurring in the regulatory regions and the non-coding RNA genes. This study demonstrated the importance of genetic changes in regulatory regions and the effectiveness of irrational ribosome engineering in creating prokaryotic microbial mutants without sufficient genetic information.

Helicobacter pylori Infection Acts as an Independent Risk Factor for Intracranial Atherosclerosis in Women Less Than 60 Years Old.

Background: Studies show inconsistent results regarding the relationship between Helicobacter pylori (H. pylori) infection and stroke. The present study assessed a potential association between H. pylori infection and an important risk factor for stroke, intracranial atherosclerosis. Methods: In total, 15,798 subjects with transcranial Doppler (TCD) and 13C-urea breath test (13C-UBT) were enrolled from March 2012 to March 2017. Intracranial atherosclerosis was further measured using intracranial carotid artery calcification (ICAC) on past or recent head CT, and 14,084 subjects were ultimately included in the study. Baseline demographics, atherosclerosis risk factors, and laboratory results were investigated. Since endothelial dysfunction is critical to the development of atherosclerosis, the role of H. pylori in migration, tube formation, and proliferation of human brain microvascular endothelial cells (HBMECs) was assessed in vitro. Results: The intracranial atherosclerosis group had a higher proportion of women and a greater rate of H. pylori infection than those without intracranial atherosclerosis. H. pylori infection was significantly more common in women with intracranial atherosclerosis than males. In addition, the incidence of intracranial atherosclerosis was significantly higher in women with H. pylori infection than uninfected women (53.8 vs. 46.4%, p < 0.001). In an adjusted model, H. pylori was shown to be an independent risk factor for intracranial atherosclerosis in women ≤ 60 years of age [odds ratio (OR) = 2.261, 95% CI = 1.839-2.780, p < 0.001]. Serum exosomes from patients with H. pylori infection had significantly reduced brain endothelial cell migration, tube formation, and proliferation in vitro. Conclusion: Helicobacter pylori infection may be an important independent risk factor for intracranial atherosclerosis in women ≤ 60 years of age.

Early Growth Trajectory of Infants With Simple Congenital Heart Disease and Complex Congenital Heart Disease Undergoing Cardiac Repair: A Prospective Cohort Study in China.

BACKGROUND: We aimed to evaluate the growth trajectory of infants with congenital heart disease (CHD) and to analyze the effects of disease classification on their growth trajectory. METHODS: A prospective cohort of infants with CHD was enrolled and divided into 2 groups: simple CHD (SC) and complex CHD (CC) groups. All patients were followed up for 6 months after CHD surgery. Weight for age (WAZ), length for age (LAZ), weight for length (WLZ), and head circumference for age were compared between the 2 groups using mixed-effects linear regression. RESULT: Between September 2018 and November 2019, 801 patients had data collected. The z-score trend decreased (e.g., ΔWAZ: 1.29±1.44) and then increased (e.g., ΔWAZ: 1.06±1.13), and all z-scores were below 0 from birth to 6 months postoperatively. Mixed-effects linear regression models indicated that the postoperative WAZ and WLZ scores of the CC group were lower than those of the SC group after adjustment (WAZ: ß = -0.72; 95% confidence interval [CI], -1.37 to -0.07; P = .03) (WLZ: ß = -0.93, 95% CI, -1.67 to -0.19; P = .01). The models also showed an interaction effect between disease classification and preoperative growth status on infant growth outcome (WAZ: interaction ß = -0.48; 95% CI, -0.88 to -0.07; P = .02) (WLZ: interaction ß = -0.36; 95% CI, -0.60 to -0.12; P = .004) (LAZ: interaction ß = -0.29; 95% CI, -0.56 to -0.02; P = .04). CONCLUSIONS: Compared with SC children, CC children have deficits in their early growth trajectories. The type of disease and preoperative growth status synergistically affect the early postoperative growth trajectory.

Comparative study of allicin-containing quadruple therapy vs. bismuth-containing quadruple therapy for the treatment of Helicobacter pylori infection: a prospective randomized study.

BACKGROUND: Bismuth has antimicrobial activity and can improve the efficacy of triple Helicobacter pylori (H. pylori) therapy. Allicin added to conventional therapy for H. pylori infection also improves H. pylori eradication rates. Thus, this study aims to evaluate and compare the efficacy, safety and tolerability of allicin-containing quadruple therapy and bismuth-containing quadruple therapy and to investigate the factors that affect the eradication rates. METHODS: Two hundred twenty H. pylori-infected patients were included and randomly (1:1) assigned to 14-day quadruple therapy: ilaprazole (5 mg bid), doxycycline (100 mg bid), and furazolidone (100 mg bid) with an allicin soft capsule (40 mg of DATS tid) (IDFA) or colloidal bismuth tartrate (220 mg of elemental bismuth bid) (IDFB). Eradication was confirmed by urea breath tests. Symptom improvement, adverse events, and adherence were assessed by a questionnaire. RESULTS: In the intention-to-treat and per-protocol analysis, the eradication rates for IDFA and IDFB groups were 87.5% (70/80) vs. 86.3% (69/80, P = 0.815) and 91.9% (68/74) vs. 91.8% (67/73, P = 0.980) as first-line therapies; 83.3% (25/30) vs. 83.3% (25/30, P = 1) and 89.3% (25/28) vs. 88.9% (24/27, P = 1) as second-line therapies. Symptom improvement rates were 96.1% and 97.0% for IDFA and IDFB (P = 1). The adverse event rates were 10.9% in IDFA and 14.5% in IDFB groups (P = 0.418). Nausea occurred frequently in IDFB than IDFA (1.8% vs. 8.2%, P = 0.030). Smoking and sharing utensils significantly affected the efficacy. CONCLUSION: Allicin-containing quadruple therapy might be regarded as a promising alternative to bismuth-containing quadruple therapy in H. pylori eradication.

Secreted Peptide PIP1 Induces Stomatal Closure by Activation of Guard Cell Anion Channels in Arabidopsis.

Plant stomata which consist of a pair of guard cells, are not only finely controlled to balance water loss as transpiration and CO2 absorption for photosynthesis, but also serve as the major sites to defend against pathogen attack, thus allowing plants to respond appropriately to abiotic and biotic stress conditions. The regulatory signaling network for stomatal movement is complex in nature, and plant peptides have been shown to be involved in signaling processes. Arabidopsis secreted peptide PIP1 was previously identified as an endogenous elicitor, which induced immune response through its receptor, RLK7. PIP1-RLK7 can activate stomatal immunity against the bacterial strain Pst DC3118. However, the molecular mechanism of PIP1 in stomatal regulation is still unclear and additional new factors need to be discovered. In this study, we further clarified that PIP1 could function as an important regulator in the induction of stomatal closure. The results showed that PIP1 could promote stomata to close in a certain range of concentrations and response time. In addition, we uncovered that PIP1-RLK7 signaling regulated stomatal response by activating S-type anion channel SLAC1. PIP1-induced stomatal closure was impaired in bak1, mpk3, and mpk6 mutants, indicating that BAK1 and MPK3/MPK6 were required for PIP1-regulated stomatal movement. Our research further deciphered that OST1 which acts as an essential ABA-signaling component, also played a role in PIP1-induced stomatal closure. In addition, ROS participated in PIP1-induced stomatal closure and PIP1 could activate Ca2+ permeable channels. In conclusion, we reveal the role of peptide PIP1 in triggering stomatal closure and the possible mechanism of PIP1 in the regulation of stomatal apertures. Our findings improve the understanding of the role of PIP1 in stomatal regulation and immune response.