Development of gut microbiota along with its metabolites of preschool children.

BACKGROUND: To reveal the changes of intestinal microbial abundance and composition, as well as the microbiota metabolic levels of bile acids and short chain fatty acids of healthy preschool children during their growth. METHODS: Feces of 120 healthy newborns and 150 healthy children aged 6 months to 6 years were collected. Then the composition of intestinal flora was analyzed by 16S rRNA, and the contents of bile acids and short chain fatty acids in feces were detected by LC-MS and GS methods, respectively. RESULTS: The composition and function of intestinal microflora were not stable in neonatal period but significantly improved at 6 months after birth, and gradually stabilized and tended to adult-like formation after 2-3 years old. The levels of short chain fatty acids and secondary bile acids were consistent with the development of gut microbiota. CONCLUSION: The age of 6 months may be a critical period for the development of intestinal microflora in children.

Integration of a pure moving bed biofilm reactor process into a large micro-polluted water treatment plant.

The pure-MBBR process was applied to remove ammonia in a full-scale micro-polluted-water treatment plant with a daily treatment capacity of 260 × 104 m3/d, Guangdong, China. The relationship between treatment efficiency, physical and chemical properties and microbial diversity in the process of biofilm growth was explored, and the oxygen transfer model of biofilm was established. The results show that the effluent of two-stage pure MBBR process is stable and up to standard after 10 days' incubation. The nitrification loads of two-stage biofilm was stable on the 14th day. The biomass and biofilm thickness lagged behind the nitrification load, and reached a relatively stable level on the 28th day. The species richness of biofilm basically reached a stable level on the 21st day, and the microbial diversity of primary biofilm was higher. In the primary and secondary stage at different periods, the relative abundance of dominant nitrifying bacteria Nitrospira reaches 8.48-13.60%, 6.48-9.27%, and Nitrosomonas reaches 2.89-5.64%, 0.00-3.48%. The pure MBBR system mainly adopts perforated aeration. Through the cutting and blocking of bubbles by suspended carriers, the oxygen transfer rate of the system was greatly improved.

Osteoarthritic infrapatellar fat pad aggravates cartilage degradation via activation of p38MAPK and ERK1/2 pathways.

OBJECTIVE: This study aimed to investigate the biochemical effects of osteoarthritic infrapatellar fat pad (IPFP) on cartilage and the underlying mechanisms. METHODS: Human IPFP and articular cartilage were collected from end-stage osteoarthritis (OA) patients during total knee arthroplasty. IPFP-derived fat-conditioned medium (FCM) was used to stimulate human primary chondrocytes and cartilage explants. Functional effect of osteoarthritic IPFP was explored in human primary chondrocytes and articular cartilage in vitro and ex vivo. Activation of relative pathways and its effects on chondrocytes were assessed through immunoblotting and inhibition experiments, respectively. Neutralization test was performed to identify the main factors and their associated pathways responsible for the effects of IPFP. RESULTS: Osteoarthritic IPFP-derived FCM significantly induced extracellular matrix (ECM) degradation in both human primary chondrocytes and cartilage explants. Several pathways, such as NF-κB, mTORC1, p38MAPK, JNK, and ERK1/2 signaling, were significantly activated in human chondrocytes with osteoarthritic IPFP-derived FCM stimulation. Interestingly, inhibition of p38MAPK and ERK1/2 signaling pathway could alleviate the detrimental effects of FCM on chondrocytes, while inhibition of other signaling pathways had no similar results. In addition, IL-1ß and TNF-α instead of IL-6 in osteoarthritic IPFP-derived FCM played key roles in cartilage degradation via activating p38MAPK rather than ERK1/2 signaling pathway. CONCLUSION: Osteoarthritic IPFP induces the degradation and inflammation of cartilage via activation of p38MAPK and ERK1/2 pathways, in which IL-1ß and TNF-α act as the key factors. Our study suggests that modulating the effects of IPFP on cartilage may be a promising strategy for knee OA intervention.

Developmental Patterns of Fecal Bile Acids in Healthy Neonates and Children.

BACKGROUND Normal profiles of FBAs in healthy neonates and children in Kunming city and surrounding areas in China have not been previously determined. The objective of this study was to determine a developmental pattern of fecal bile acids (FBAs) in healthy neonates and children. MATERIAL AND METHODS A cross-sectional study was performed on 238 healthy neonates and children recruited in the First Affiliated Hospital of Kunming Medical University, China from October 2015 to September 2016. Secreted primary and secondary FBAs in fresh feces were quantitated by liquid chromatography mass spectrometry (LC-MS). Amounts of FBAs in feces were compared among various age groups. RESULTS Trace amounts of cholic acid and chenodiol acid of primary FBAs were detectable at day 3 after birth, with a significant increase from day 3 to day 7. The primary FBAs gradually decreased from day 25 to the age of 6 years old. In contrast, a significant amount of glycochenodeoxycholic acid was detected on day 3 but decreased to a trace amount by day 7 and onwards. Primary FBAs appeared to maintain a high level, accounting for 98% of total FBAs, with no significant changes from day 7 to day 25 after birth. They gradually decreased from 90% to 10% from age 6 months to 6 years old. While the secondary FBAs were barely detected in neonates, only accounting for 2% of total FBAs, they were gradually elevated to 90% of total FBAs from age 6 months to 6 years old. CONCLUSIONS The liver can effectively synthesize primary bile acids 7 days after birth, and fecal primary bile acids tend to be stable after the neonate stage. Secondary bile acids continuously increase along with the maturation of intestinal flora, which reaches a relatively stable level at around 3 years old.

Epidemiology and genetic diversity of group A rotavirus in acute diarrhea patients in pre-vaccination era in southwest China.

Group A rotavirus (RVA) is one of the leading cause of acute diarrhea worldwide, the RVA-related disease burden and the genotypes of RVA is important reference to introduce RVA variance to national immunisation programmes, 1,121 diarrhea cases and 319 healthy controls were recruited from four sentinel hospital outpatient from July 2014 to June 2015. The prevalence of RVA was 244 (21.8%) in gastroenteritis cases and in 12 (3.8%) in healthy controls across all age group (OR = 7.12, 95%CI = 3.93-12.89); the detection rate of RVA in diarrhea patients under 5 years was more higher than in diarrhea cases over 5 years (26.1%, 222/850; 8.1%, 22/271, respectively, P = 0.000). Of 244 RVA strains isolated from acute diarrhea cases, G9 (66.4%) was predominant G genotype, followed by G3 (18.7%), G1 (8.9%), and G1G3 (3.8%); P[8] was the overwhelming prevalence P genotype, followed by P[4] (4.7%); G9P[8] (54.9%) was most common G and P Combination, followed by G3P[8] (17.6%) and G1[8] (8.6%). The conclusion of the study was important to provide reference for introducing the RVA vaccine to prevent and control RVA-associated disease burden. J. Med. Virol. 89:71-78, 2017. © 2016 Wiley Periodicals, Inc.

Emergence of human caliciviruses among diarrhea cases in southwest China.

BACKGROUND: Acute diarrhea is one of the most serious problems in global public health that causes considerable morbidity and mortality worldwide. Human caliciviruses (HuCV) including norovirus (NoV, genogroup GI and GII) and sapovirus (SaV), is a leading cause of acute sporadic diarrhea in individuals across all age groups. However, few studies had been conducted clarifying the characteristics of HuCV in diarrhea cases across all age groups in China. Our study was aimed at assessing the HuCV-related diarrhea burden and NoV genotypes distribution in southwest China. METHODS: The study was conducted in four hospitals in Kunming city, Yunnan province, from June 2014 to July 2015. Stool specimens were collected from 1,121 diarrhea cases and 319 healthy controls in outpatient departments. Reverse transcription polymerase chain reaction (RT-PCR) was used to detect NoV (GI, GII) and SaV. Sequencing was applied to confirm the three viral infections and phylogenetic analysis was performed to determine their genotypes. A structured questionnaire was used to record the demographic information and clinical symptoms of subjects. RESULTS: HuCV was detected at an 11.0 % infection rate in 1,121 diarrhea cases and at 3.4 % rate in 319 non-diarrhea subjects (p < 0.0001, OR = 3.5, 95 % CI 1.8-6.5). The prevalence of the NoV genogroup GII and genotype GII.4 in diarrhea cases was significantly higher than that found in healthy controls (p < 0.0001, p = 0.018, respectively). NoV GII (n = 118, 10.5 %) was the most common HuCV subtype in diarrhea cases, followed by SaV (n = 3, 0.3 %) and NoV GI (n = 2, 0.2 %). Of 118 NoV GII strains isolated from diarrhea patients. GII.4 (n = 55, 46.6 %) was the predominant strain, followed by GII.3 (n = 28, 23.7 %), GII.12 (n = 25, 21.2 %), GII.17 (n = 8, 6.8 %), and GII.5 (n = 2, 1.7 %). Of the 55 GII.4 strains, the GII.4 Sydney 2012 variant had absolutely predominant prevalence (n = 52, 94.5 %), followed by the NoV GII.4-2006b variant (n = 3, 5.5 %). The GII.4 Orleans 2009 variant was not found in diarrhea cases of the study. CONCLUSIONS: NoV GII was the major genogroup and GII.4 was the most predominant strain detected in diarrhea patients. The GII.17 is an emergent variant in sporadic diarrhea and might become the predominant strain in diarrhea cases in the near future. Rapid, accurate detection kits need to be developed to help us find and treat NoV-associated diarrhea in clinical settings in a timely manner.

Application Effect of Different Concentrations of Platelet-Rich Plasma Combined with Quadriceps Training on Cartilage Repair of Knee Osteoarthritis.

We investigated the application effect of different concentrations of platelet-rich plasma (PRP) combined with quadriceps training on cartilage repair of knee osteoarthritis. Data of 37 patients with knee osteoarthritis (KOA) treated in our hospital (November 2019-February 2021) were retrospectively analyzed and the patients were divided into low concentration group (LCG) (n = 12), medium concentration group (MCG) (n = 12), and high concentration group (HCG) (n = 13) according to the order of admission. All patients received quadriceps training. Three groups above received knee injection of PRP, and the platelet concentrations were 1000-1400 × 109/L, 1400-1800 × 109/L, and 1800-2100 × 109/L, respectively. Articular cartilage thickness of the medial and lateral femur, knee joint function scores, inflammatory factor levels, and matrix metalloproteinases (MMPs) levels were compared. After treatment, compared with the MCG and HCG, articular cartilage thickness of the medial and lateral femur of the diseased side in the LCG was obviously lower (P < 0.05). At 2 months after treatment (T 3), compared with the HCG, articular cartilage thickness of the medial and lateral femur of the diseased side in the MCG was obviously higher (P < 0.05), without remarkable difference in articular cartilage thickness of the medial and lateral femur of the healthy side among three groups (P > 0.05). After treatment, compared with the LCG, knee joint function scores of the MCG and HCG were obviously better (P < 0.001). Compared with the HCG, the knee function score at T 3 in the MCG was obviously better (P < 0.001). After treatment, compared with the LCG, inflammatory factor levels and levels of MMPs in the MCG and HCG were obviously lower (P < 0.05). Compared with the HCG, inflammatory factor levels and levels of MMPs at T 3 in the MCG were obviously lower (P < 0.05). PRP combined with quadriceps training can accelerate cartilage repair of patients with KOA and reduce inflammatory factor levels and levels of MMPs, but the treatment effect of PRP depends on platelet concentration, with the best range of 1400-1800 × 109/L. Too high or too low platelet concentrations will affect recovery of knee function.

Antibiotic resistance and genomic features of Clostridioides difficile in southwest China.

Background: Clostridioides difficile infection (CDI) caused by toxigenic strains leads to antibiotic-related diarrhea, colitis, or even fatal pseudomembranous enteritis. Previously, we conducted a cross-sectional study on prevalence of CDI in southwest China. However, the antibiotics resistance and characteristics of genomes of these isolates are still unknown. Methods: Antibiotic susceptibility testing with E-test strips and whole genome sequence analysis were used to characterize the features of these C. difficile isolates. Results: Forty-nine strains of C. difficile were used in this study. Five isolates were non-toxigenic and the rest carried toxigenic genes. We have previously reported that ST35/RT046, ST3/RT001 and ST3/RT009 were the mostly distributed genotypes of strains in the children group. In this study, all the C. difficile isolates were sensitive to metronidazole, meropenem, amoxicillin/clavulanic acid and vancomycin. Most of the strains were resistant to erythromycin, gentamicin and clindamycin. The annotated resistant genes, such as macB, vanRA, vanRG, vanRM, arlR, and efrB were mostly identified related to macrolide, glycopeptide, and fluoroquinolone resistance. Interestingly, 77.55% of the strains were considered as multi-drug resistant (MDR). Phylogenetic analysis based on core genome of bacteria revealed all the strains were divided into clade 1 and clade 4. The characteristics of genome diversity for clade 1 could be found. None of the isolates showed 18-bp deletion of tcdC as RT027 strain as described before, and polymorphism of tcdB showed a high degree of conservation than tcdA gene. Conclusions: Most of the C. difficile isolates in this study were resistant to macrolide and aminoglycoside antibiotics. Moreover, the MDR strains were commonly found. All the isolates belonged to clade 1 and clade 4 according to phylogenetic analysis of bacterial genome, and highly genomic diversity of clade 1 was identified for these strains.

The Emerging Roles of the RNA Binding Protein QKI in Cardiovascular Development and Function.

RNA binding proteins (RBPs) have a broad biological and physiological function and are critical in regulating pre-mRNA posttranscriptional processing, intracellular migration, and mRNA stability. QKI, also known as Quaking, is a member of the signal transduction and activation of RNA (STAR) family, which also belongs to the heterogeneous nuclear ribonucleoprotein K- (hnRNP K-) homology domain protein family. There are three major alternatively spliced isoforms, QKI-5, QKI-6, and QKI-7, differing in carboxy-terminal domains. They share a common RNA binding property, but each isoform can regulate pre-mRNA splicing, transportation or stability differently in a unique cell type-specific manner. Previously, QKI has been known for its important role in contributing to neurological disorders. A series of recent work has further demonstrated that QKI has important roles in much broader biological systems, such as cardiovascular development, monocyte to macrophage differentiation, bone metabolism, and cancer progression. In this mini-review, we will focus on discussing the emerging roles of QKI in regulating cardiac and vascular development and function and its potential link to cardiovascular pathophysiology.

Expression level of miRNA in the peripheral blood of patients with multiple myeloma and its clinical significance.

OBJECTIVE: To investigate the expression level of serum miRNA-192-5p and its clinical value in the diagnosis and care of patients with multiple myeloma (MM). METHODS: Eighty-eight patients with MM admitted to our hospital from June 2017 to April 2020 were selected as the observation group. In addition, 70 patients who received osteoporosis testing in our hospital in the corresponding period but were excluded from having MM and haematological malignancy were selected as the control group. The relative expression level of serum miRNA-192-5p was detected. The expression level of serum miRNA and its correlation with patient-related clinical parameters were compared and analyzed. The ROC curve was used to analyze its diagnostic efficacy for MM. RESULTS: The relative expression level of serum miRNA-192-5p in MM patients was remarkably lower than that in the control group (P < 0.05); the AUC area of serum miRNA-192-5p in patients with a diagnosis of MM was 0.853, with a cutoff value of 0.72, the sensitivity of 86.30%, and the specificity of 81.20%, P = 0.030. The relative expression level of miRNA-192-5p in the serum of patients with high ß2-MG and creatinine levels was markedly reduced compared to that in patients with low ß2-MG levels (P < 0.05); the relative expression level of miRNA-192-5p in the serum of patients with low hemoglobin and albumin levels was markedly reduced compared to that in patients with normal hemoglobin and albumin (P < 0.05); and there was significantly negative correlation between the relative expression level of miRNA-192-5p in the serum of MM patients and IgG and IgA levels, respectively (P < 0.05). CONCLUSION: miRNA-192-5p may serve as an auxiliary diagnostic tool in the diagnosis of MM. Furthermore, because there is certain correlation between serum miRNA-192-5p and MM progression and prognosis, it may be regarded as a novel marker for MM monitoring.

Gut Microbiota Dysbiosis Associated with Bile Acid Metabolism in Neonatal Cholestasis Disease.

Neonatal cholestasis disease (NCD) is a complex and easily mis-diagnosed condition. We analyzed microbiota community structure in feces and measured short-chain fatty acids, bile acids (BAs) and liver function of 12 healthy, 13 NCD, and 13 treated infants after diagnosis. Based on 16S rRNA gene amplicon sequencing and gas-chromatographic-mass-spectrometric analysis of secondary BAs, we identified microbial genera and metabolites that associate with abnormal bile secretion. Streptococcus gallolyticus and Parabacteroides distasonis, and Lactobacillus gasseri had higher relative abundance in healthy and NCD infants respectively. Compared to NCD patients, healthy infants had higher LCA, CDCA and GCDCA fecal concentrations. The three microbial species and three secondary bile acids were selected as potential non-invasive combined biomarkers to diagnose NCD. We propose that microbiota-metabolite combined biomarkers could be used for diagnosis of NCD, and this may contribute to improved early clinical diagnosis of NCD in the future.

Molecular functions of FSTL1 in the osteoarthritis.

Follistatin-like protein 1 (FSTL1) showed overexpression in the inflammatory synovial pannus, serum, and synovial tissues of osteoarthritis (OA) patients. However, FSTL1 knock out (KO) embryos exhibited reduced vertebral cartilage cellularity, extensive skeleton defects and reduced MSCs proliferation. Thus, the role of FSTL1 in chondrocyte proliferation is not completely understood. In vitro studies revealed that Human recombinant FSTL1 (hFSTL1) promoted chondrogenic signals in the MSCs and cell viability only at low concentrations. Recent reports suggest that high levels of FSTL-1 are proposed to enhance inflammatory signals which suppress chondrogenesis leading to cartilage destruction. Altogether, FSTL1 has the potential to promote MSC proliferation and chondrogenic differentiation in a low concentration-dependent manner. However, the mechanism by which FSTL-1 affects MSCs chondrogenic differentiation and chondrogenesis remains unknown. Therefore, this review introduces a deep discussion of FSTL1's molecular functions in the OA pathophysiology, which will contribute to the deep understanding of FSTL1 molecular activity in the OA pathogenesis.

Biomechanical Study of Screw Fixation and Plate Fixation of a Posterior Malleolar Fracture in a Simulation of the Normal Gait Cycle.

BACKGROUND: Fixation of posterior malleolar fractures with plates or screws is under debate. A fatigue loading system and a spatial motion capture system were used in this study to evaluate a posterior malleolar fracture model. METHODS: Thirty-six below-knee specimens with a single posterolateral fragment (Haraguchi I) type posterior malleolar fracture models were randomly divided into 2 groups. Two parallel-placed 3.5-mm partially threaded titanium alloy screws were used in Group A to fix the fractures, while anatomical plates were used in Group B. According to the ratio (S) of the area between the fracture and the total articular surface, each group was subdivided into 3 subgroups. In group A1 and B1, S=1/4; in A2 and B2, S=1/3; and in A3 and B3, S=1/2. To simulate the gait cycle, each specimen was subjected to mechanical loading in 4 different ankle positions. A fatigue loading system was used for repeated loading. A spatial motion capture system was used to measure the displacement in the final loading stage. RESULTS: Despite the limited sample size and relatively low power, no significant difference was observed between A1 and B1, A2 and B2, and A3 and B3 in all 4 ankle positions after repeated loading. CONCLUSION: For a Haraguchi type I posterior malleolar fracture with an average height of 19 mm, fixation with a posterior malleolar anatomical plate failed to demonstrate a stronger strength than 2 parallel-placed 3.5-mm partially threaded screws, which indicates that plates may not be absolutely necessary for standard rehabilitation after posterior malleolar internal fixation. CLINICAL RELEVANCE: These findings may help guide surgeons with regard to fixation requirements for posterior malleolar fractures.

Treatment of Medial Malleolus or Pure Deltoid Ligament Injury in Patients with Supination-External Rotation Type IV Ankle Fractures.

OBJECTIVE: To investigate the effect of internal fixation on postoperative ankle function in patients with supination-external rotation type IV ankle fractures, including medial malleolus fractures and deltoid ligament injury. METHODS: Between January 2012 and June 2014, patients with medial structure injuries were enrolled in this study and assigned to the medial malleolus fracture group or the deltoid ligament group. The surgical procedures for the two groups were documented. The follow-up endpoint was the time point when the steel plate or screw was removed from the lateral ankle. The Olerud-Molander ankle scoring system was used to assess ankle function. RESULTS: A total of 84 patients with supination-external rotation type IV ankle fractures had complete medical records and were included in this study. The average age of the patients was 44.16 years (range, 15-75). The patient sample included 39 males and 45 females. Overall, 49 patients (19 males and 30 females) suffered a medial malleolus fracture. The average age of these patients was 40.20 years (range, 15-75). Patients with a posterior malleolar fracture fragment >25% of the articular surface accounted for 81.6% (40 patients) of these patients. Overall, 35 patients (20 males and 15 females) experienced a deltoid ligament injury. The average age of these patients was 44.21 years (range, 17-73). Patients with a posterior malleolar fracture fragment >25% of the articular surface accounted for 11.5% (four patients) of these patients. Open reduction was performed in patients with medial malleolus fractures, and two 4.0-mm cannulated screws were used to fixate the posterior malleolus and the medial malleolus. The suture-anchor technique was used to repair the ligaments in patients with deltoid ligament injuries. The follow-up endpoint was the time point when the steel plate and screws were removed from the lateral ankle in patients. The average follow-up period was 13.4 months (range, 11-17). The Olerud-Molander ankle scoring system was used to assess postoperative ankle function. The average score for the patients in the medial malleolus fracture group was 90.3 points (range, 85-95). The average score for the patients in the deltoid ligament injury group was 87.7 points (range, 80-95). No significant differences were found in the scores between the two groups. CONCLUSION: Medial malleolus fracture and deltoid ligament injury are two different presentations of supination-external rotation type IV ankle fractures. Anatomic reduction of the articular surface concurrent with restoration of ankle stability can achieve favorable results for these two injuries.

Impact of co-infections with enteric pathogens on children suffering from acute diarrhea in southwest China.

BACKGROUND: Acute diarrhea is a global health problem, resulting in high morbidity and mortality in children. It has been suggested that enteric pathogen co-infections play an important role in gastroenteritis, but most research efforts have only focused on a small range of species belonging to a few pathogen groups. This study aimed to assess the impact of co-infections with a broad range of enteric pathogens on children aged below five years who suffer from acute diarrhea in southwest China. METHOD: A total of 1020 subjects (850 diarrhea cases and 170 healthy controls) were selected from four sentinel hospitals in Kunming, Yunnan province, southwest China, from June 2014 to July 2015. Stool specimens were collected to detect five virus (rotavirus group A, RVA; norovirus, NoV; Sapovirus, SaV; astrovirus, As; and adenovirus, Ad), seven bacterial (diarrheagenic Escherichia coli, DEC; non-typhoidal Salmonella, NTS; Shigella spp.; Vibrio cholera; Vibrio parahaemolyticus; Aeromonas spp.; and Plesiomonas spp.), and three protozoan (Cryptosporidium spp., Giardia lamblia, and Blastocystis hominis, B. hominis) species using standard microbiologic and molecular methods. Data were analyzed using the partial least square regression technique and chi-square test. RESULTS: At least one enteric pathogen was detected in 46.7 % (n = 397) of acute gastroenteritis cases and 13.5 % (n = 23) of healthy controls (χ(2) = 64.4, P < 0.05). Single infection with RVA was associated with acute diarrhea (26.5 % vs. 5.8 %, P < 0.05). The prevalence of a single infection with B. hominis in diarrhea cases was higher than in healthy controls (3.1 % vs. 0.5 %, OR = 4.7, 95 % CI: 1.01-112.0). Single infection with NoV GII was not associated with diarrhea (4.4 % vs. 3.5 %, OR = 1.2, 95 % CI: 0.5-3.3). Single infections with bacterial species were not observed. The prevalence of co-infections with two enteric pathogens in diarrhea cases was higher than in asymptomatic children (20.1 % vs. 5.3 %, P < 0.05). RVA-NoV GII was the most common co-infection in symptomatic children (4.4 %), with it aggravating the severity of diarrhea. CONCLUSIONS: Although it is clear that RVA has an overwhelming impact on diarrhea illnesses in children, co-infection with other enteric pathogens appears to also aggravate diarrhea severity. These findings should serve as evidence for public health services when planning and developing intervention programs.

Molecular characteristics of Salmonella enterica Paratyphi A in Yunnan Province, southwest China.

Previously, the prevalence of Salmonella enterica Paratyphi A in Yunnan was high; and recently Yunnan was the predominant endemic province in China. To identify the molecular epidemiology, antibiotic resistance profile and genotypic diversity of the S. Paratyphi A isolates from 1995 to 2013 in Yunnan, we performed the study. Antibiotic susceptibility tests, pulse-field gel electrophoresis (PFGE) and multilocus sequence typing (MLST) were used to identify the characteristics of the bacterial isolates. The results showed from 1995 to 2013, 366 S. Paratyphi A were isolated: 295 isolates (80.6%) from Yuxi and 68 isolates (18.58%) from Honghe. All of the strains were resistant to nalidixic acid, and some were resistant to ampicillin and trimethoprim/sulfamethoxazole in different years. All the isolates were sensitive to cefotaxime and ciprofloxacin. Identical PFGE with two enzyme digestion patterns were found for 339 isolates. Some environmental isolates in different years were homologous with the strains isolated from food and patients. MLST showed 349 strains were ST85, only 17 isolates were ST129. S. Paratyphi A isolates from Yunnan showed a high similarity, and we found the pathogen isolated from patients, the environment and food had the close epidemiological relationship, forming a transmission circulation. These findings have important implications for paratyphoid-control strategies.

Characterization of Vibrio cholerae from 1986 to 2012 in Yunnan Province, southwest China bordering Myanmar.

Vibrio cholerae is an important infectious pathogen causing serious human diarrhea. We analyzed 568 V. cholerae strains isolated from 1986 to 2012 in Yunnan province, southwest China bordering Myanmar. Polymerase chain reactions for detecting virulence genes, antibiotic susceptibility tests and pulse-field gel electrophoresis (PFGE) were performed. The results showed all the strains were El Tor biotype from 1986. The ctxB subunit sequence analysis for all strains have shown that cholera between 1986 and 1995 was associated with mixed infections with El Tor and El Tor variants, while infections after 1996 were all caused by El Tor variant strains. All of the strains were sensitive to aminoglycosides and quinolone antibiotics while resistant to ß-lactamase and carbapenem antibiotics increased gradually. 568 V. cholerae were divided into 218 PFGE-NotI patterns, and the isolates before 2001 and after 2011 were separated into two groups according to PFGE results. The strains isolated before 2001 were mainly referred to native cholera in Yunnan, and after 2011 were primarily referred to as imported strains from Myanmar, which showed the variation of V. cholerae in this area. The molecular characteristics of V. cholerae indicated regularity in bacterial variation and evolution in Yunnan province.