0
selected
-
1.
Transcriptional profiling of Pseudomonas aeruginosa PAO1 in response to anti-biofilm and anti-infection agent exopolysaccharide EPS273.
Wu, Z, Zheng, R, Zhang, J, Wu, S
Journal of applied microbiology. 2021;(1):265-277
Abstract
AIMS: Relatively, few anti-biofilm polysaccharides against Pseudomonas aeruginosa were done to investigate the underlying molecular mechanism. Exopolysaccharide EPS273 can clearly reduce biofilm formation and infection of P. aeruginosa. This study aims to investigate its anti-biofilm and anti-infection mechanism on transcriptional level. METHODS AND RESULTS Herein, we used an RNA-Seq transcriptomic approach to investigate the underlying anti-biofilm and anti-infection mechanism of EPS273. The expression levels of a large number of genes were changed after P. aeruginosa PAO1 was treated with EPS273. Especially, the genes related to biofilm formation, such as gene involved in production of extracellular matrix and virulence factor, genes involved in flagella and cell motility and genes involved in iron acquisition. Notably, the expression levels of genes involved in regulatory and signal transduction were markedly downregulated, such as two-component system PhoP-PhoQ and quorum sensing (QS) system LasI/LasR and RhlI/RhlR. Furthermore, when genes phoP and phoQ were disrupted, respectively, the reduction of biofilm formation and cell motility in mutant △phoP or △phoQ was also detected. CONCLUSION EPS273 may exert its anti-biofilm and anti-infection function by downregulating gene expression of two-component system PhoP-PhoQ and QS systems LasI/LasR and RhlI/RhlR of P. aeruginosa, which further regulated expression of genes involved in biofilm formation. SIGNIFICANCE AND IMPACT OF THE STUDY Our data will expand understanding of anti-biofilm mechanisms of polysaccharides on transcriptomic level.
-
2.
Probiotics, prebiotics, antibiotic, Chinese herbal medicine, and fecal microbiota transplantation in irritable bowel syndrome: Protocol for a systematic review and network meta-analysis.
He, Y, Xu, R, Wang, W, Zhang, J, Hu, X
Medicine. 2020;(32):e21502
-
-
Free full text
-
Abstract
BACKGROUND Irritable bowel syndrome (IBS) is a functional gastrointestinal disease, with a high global incidence, which seriously influences the quality of life and work efficiency of patients. Extensive research showed that IBS is related to changes in the intestinal microenvironment. The novel treatment strategy targeting the gut microbiota is being actively implemented. Probiotics, antibiotics, prebiotics, fecal microbiota transplantation, and Chinese Herbal Medicine have been proven to be effective in the treatment of IBS, and all have an impact on the intestinal flora of patients. However, these 5 treatments have their own pros and cons and have not been systematically evaluated and compared. Therefore, this study will indirectly compare the safety and effectiveness of these 5 methods in the treatment of IBS through network meta-analysis. METHODS The following databases including Embase, Pubmed, Cochrane Central Register of Controlled Trials, Chinese Biomedical Literature Database, WHO International Clinical Trials Registry Platform and ClinicalTrials.gov will be retrieved from inception to June 2020 without language restrictions. Literature selection, data extraction, and bias analysis will be done by 2 researchers. The primary outcome is global symptoms improvement. The secondary outcomes will include individual IBS symptom scores, emotional response, and adverse events. The conventional pair-wise meta-analysis will be performed using Stata V.14.0 and be pooled using a random-effects model. We will use WinBUGS V.1.4.3 (Cambridge, United Kingdom) with a Bayesian hierarchical random-effects model to conduct the network meta-analysis. RESULTS This study will provide systematic reviews and indirect network comparison results about treatments of IBS. CONCLUSIONS This study will systematically evaluate and compare 5 intestinal flora-related therapies for IBS and to provide an evidence-based medical decision-making basis for clinicians. TRIAL REGISTRATION NUMBER INPLASY202050047.
-
3.
Vancomycin in peritoneal dialysis: Clinical pharmacology considerations in therapy.
Lam, E, Lien, YTK, Kraft, WK, Piraino, B, Vozmediano, V, Schmidt, S, Zhang, J
Peritoneal dialysis international : journal of the International Society for Peritoneal Dialysis. 2020;(4):384-393
-
-
Free full text
-
Abstract
Intraperitoneal vancomycin is the first-line therapy in the management of peritoneal dialysis (PD)-related peritonitis. However, due to the paucity of data, vancomycin dosing for peritonitis in patients on automated peritoneal dialysis (APD) is empiric and based on clinical experience rather than evidence. Studies in continuous ambulatory peritoneal dialysis (CAPD) patients have been used to provide guidelines for dosing and are often extrapolated for APD use, but it is unclear whether this is appropriate. This review summarizes the available pharmacokinetic data used to inform optimal dosing in patients on CAPD or APD. The determinants of vancomycin disposition and pharmacodynamic effects are critically summarized, knowledge gaps explored, and a vancomycin dosing algorithm in PD patients is proposed.
-
4.
Efficacy of proprietary Lactobacillus casei for anti-tuberculosis associated gastrointestinal adverse reactions in adult patients: a randomized, open-label, dose-response trial.
Lin, S, Zhao, S, Liu, J, Zhang, J, Zhang, C, Hao, H, Sun, Y, Cai, J, Yang, Y, Ma, Y, et al
Food & function. 2020;(1):370-377
Abstract
Anti-tuberculosis (TB) drugs can induce a series of gastrointestinal adverse events, which can seriously affect patients' quality of life and may lead to treatment failure. Studies have shown that probiotics treatments can improve antibiotic-induced gastrointestinal symptoms. In this randomized, open-label, dose-response clinical trial, we investigated the preventive effects of Lactobacillus casei on anti-TB-induced gastrointestinal adverse events. In total, 429 adult patients who underwent intensive-phase anti-TB therapy were included and randomly assigned to consume one bottle of L. casei of per day (low-dose group, n = 142), two bottles of L. casei per day (high-dose group, n = 143), or no intervention (control group, n = 144) for 2 months. Each bottle of L. casei contained 10 billion colony-forming units of live L. casei. Patients' daily gastrointestinal symptoms were recorded during the intervention period. After 2 months of L. casei consumption, 397 patients had completed the intervention. Both the high and low dose L. casei groups (37.6% and 29.4%, respectively) had lower incidences of anti-TB-associated total gastrointestinal adverse events than the control group (50.0%). The high and low dose L. casei groups (3.5 d and 5.8 d, respectively) also had shorter duration anti-TB-associated adverse gastrointestinal symptoms than the control group (6.2 d). Regarding individual symptoms, the higher L. casei dose resulted in a lower incidence of vomiting and appetite loss. Similar dose-dependent protective effects of L. casei were observed regarding the duration of vomiting and appetite loss. These findings indicated that daily L. casei consumption prevented anti-TB-associated gastrointestinal adverse events. This trial was registered at the Chinese Clinical Trial Register (ChiCTR-IOR-17013210).
-
5.
Whole-genome sequencing reveals the mechanisms for evolution of streptomycin resistance in Lactobacillus plantarum.
Zhang, F, Gao, J, Wang, B, Huo, D, Wang, Z, Zhang, J, Shao, Y
Journal of dairy science. 2018;(4):2867-2874
Abstract
In this research, we investigated the evolution of streptomycin resistance in Lactobacillus plantarum ATCC14917, which was passaged in medium containing a gradually increasing concentration of streptomycin. After 25 d, the minimum inhibitory concentration (MIC) of L. plantarum ATCC14917 had reached 131,072 µg/mL, which was 8,192-fold higher than the MIC of the original parent isolate. The highly resistant L. plantarum ATCC14917 isolate was then passaged in antibiotic-free medium to determine the stability of resistance. The MIC value of the L. plantarum ATCC14917 isolate decreased to 2,048 µg/mL after 35 d but remained constant thereafter, indicating that resistance was irreversible even in the absence of selection pressure. Whole-genome sequencing of parent isolates, control isolates, and isolates following passage was used to study the resistance mechanism of L. plantarum ATCC14917 to streptomycin and adaptation in the presence and absence of selection pressure. Five mutated genes (single nucleotide polymorphisms and structural variants) were verified in highly resistant L. plantarum ATCC14917 isolates, which were related to ribosomal protein S12, LPXTG-motif cell wall anchor domain protein, LrgA family protein, Ser/Thr phosphatase family protein, and a hypothetical protein that may correlate with resistance to streptomycin. After passage in streptomycin-free medium, only the mutant gene encoding ribosomal protein S12 remained; the other 4 mutant genes had reverted to the wild type as found in the parent isolate. Although the MIC value of L. plantarum ATCC14917 was reduced in the absence of selection pressure, it remained 128-fold higher than the MIC value of the parent isolate, indicating that ribosomal protein S12 may play an important role in streptomycin resistance. Using the mobile elements database, we demonstrated that streptomycin resistance-related genes in L. plantarum ATCC14917 were not located on mobile elements. This research offers a way of combining laboratory evolution techniques and whole-genome sequencing for evaluating antibiotic resistance in probiotics.
-
6.
Direct Genetic and Enzymatic Evidence for Oxidative Cyclization in Hygromycin B Biosynthesis.
Li, S, Zhang, J, Liu, Y, Sun, G, Deng, Z, Sun, Y
ACS chemical biology. 2018;(8):2203-2210
Abstract
Hygromycin B is an aminoglycoside antibiotic with a structurally distinctive orthoester linkage. Despite its long history of use in industry and in the laboratory, its biosynthesis remains poorly understood. We show here, by in-frame gene deletion in vivo and detailed enzyme characterization in vitro, that formation of the unique orthoester moiety is catalyzed by the α-ketoglutarate- and non-heme iron-dependent oxygenase HygX. In addition, we identify HygF as a glycosyltransferase adding UDP-hexose to 2-deoxystreptamine, HygM as a methyltransferase responsible for N-3 methylation, and HygK as an epimerase. These experimental results and bioinformatic analyses allow a detailed pathway for hygromycin B biosynthesis to be proposed, including the key oxidative cyclization reactions.
-
7.
Ciprofloxacin inhibits advanced glycation end products-induced adhesion molecule expression on human monocytes.
Mori, S, Takahashi, HK, Liu, K, Wake, H, Zhang, J, Liu, R, Yoshino, T, Nishibori, M
British journal of pharmacology. 2010;(1):229-40
-
-
Free full text
-
Abstract
BACKGROUND AND PURPOSE Advanced glycation end products (AGEs) subtypes, proteins or lipids that become glycated after exposure to sugars, can induce complications in diabetes. Among the various AGE subtypes, glyceraldehyde-derived AGE (AGE-2) and glycolaldehyde-derived AGE (AGE-3) are involved in inflammation in diabetic patients; monocytes are activated by these AGEs. Ciprofloxacin (CIP), a fluorinated 4-quinolone, is often used clinically to treat infections associated with diabetis due to its antibacterial properties. It also modulates immune responses in human peripheral blood mononuclear cells (PBMC) therefore we investigated the involvement of AGEs in these effects. EXPERIMENTAL APPROACH Expression of intercellular adhesion molecule (ICAM)-1, B7.1, B7.2 and CD40 was examined by flow cytometry. The production of tumour necrosis factor (TNF)-alpha, interferon (IFN)-gamma, prostaglandin E(2) (PGE(2)) and cAMP were determined by enzyme-linked immunosorbent assay. Cyclooxygenase (COX)-2 expression was determined by Western blot analysis. Lymphocyte proliferation was determined by [(3)H]-thymidine uptake. KEY RESULTS CIP induced PGE(2) production in monocytes, irrespective of the presence of AGE-2 and AGE-3, by enhancing COX-2 expression; this led to an elevation of intracellular cAMP in monocytes. Non-selective and selective COX-2 inhibitors, indomethacin and NS398, inhibited CIP-induced PGE(2) and cAMP production. In addition, CIP inhibited AGE-2- and AGE-3-induced expressions of ICAM-1, B7.1, B7.2 and CD40 in monocytes, the production of TNF-alpha and IFN-gamma and lymphocyte proliferation in PBMC. Indomethacin, NS398 and a protein kinase A inhibitor, H89, inhibited the actions of CIP. CONCLUSIONS AND IMPLICATIONS CIP exerts immunomodulatory activity via PGE(2), implying therapeutic potential of CIP for the treatment of AGE-2- and AGE-3-induced inflammatory responses.