Epidemiological and Whole-Genome Sequencing Analysis of a Gastroenteritis Outbreak Caused by a New Emerging Serotype of Vibrio parahaemolyticus in China.

Vibrio parahaemolyticus is an important foodborne pathogen with diverse serotypes. In May 2021, we investigated a gastroenteritis outbreak that occurred in China, caused by V. parahaemolyticus O10:K4 infection. Based on the epidemiological curve, this outbreak was identified as a homologous exposure event. A case-control study demonstrated that emperor crab with mashed garlic (odds ratio [OR] = 4.60, p = 0.030; 95% confidence interval [95% CI]: 1.11-19.14), goose liver geoduck (OR = 4.50, p = 0.029; 95% CI: 1.12-18.13), shrimp (OR = 4.89, p = 0.021; 95% CI: 1.22-19.65), and sea cucumber (OR = 7.36, p = 0.005; 95% CI: 1.68-32.26) were the potential sources of the food poisoning. V. parahaemolyticus isolates from 18 laboratory-confirmed cases were all serotyped O10:K4, and determined to be sequence type ST3 via multilocus sequence typing. Pulsed field gel electrophoresis and whole-genome sequencing analysis revealed the identical pattern and 0-2 single nucleotide variation among these isolates. tdh was positive in all isolates, while trh and Orf8 were absent. Seven essential base positions in toxRS for pandemic clone identification were identical between the O10:K4 and O3:K6 pandemic clones. Phylogenetic analysis with 45 additional genomes of 13 different serotypes showed the closest genetic relationship between O10:K4 and O1: KUT. O10:K4 was thought to evolve from the O3:K6 pandemic clone. The new serovariant of O3:K6 poses a challenge for the prevention and control of V. parahaemolyticus disease outbreaks, or even epidemics, in the future.

Mini-laparoscopic pyeloplasty to treat UPJO in infants.

PURPOSE: The aim of this study was to investigate the safety and clinical efficacy of mini-laparoscopic pyeloplasty in treating ureteropelvic junction obstruction (UPJO) in infants. MATERIAL AND METHODS: We retrospectively analysed the clinical data of 66 infants with UPJO from January 2013 to August 2018 at our hospital. They were divided into the laparoscopic surgery group (group A) and the open surgery group (group B), depending on the surgical method. RESULTS: The bleeding volume, analgesia duration, postoperative hospitalization duration, and incision length in group A were significantly less than those in group B (p < .05). The incidence of incision dehiscence was 0% in group A and 11.7% in group B (p = .045). At the postoperative follow-up, the incidence of anastomotic stenosis was 6.2% in group A and 5.9% in group B (p = .719). The anteroposterior diameter and glomerular filtration rate were significantly improved at the one-year follow-up, but there was no significant difference between the groups (p > .05). CONCLUSIONS: Mini-laparoscopic pyeloplasty to treat UPJO in infants has the same early clinical efficacy and safety as open surgery, and this procedure has the advantages of fewer incisions, less pain, quicker recovery, and better cosmetic outcomes.

Single-port laparoscopic percutaneous closure of the internal ring for scarless repair of inguinal hernias in girls.

PURPOSE: The purpose of this study was to summarize the clinical experience with laparoscopic percutaneous extraperitoneal closure of the internal ring using an epidural needle for inguinal hernias in girls. MATERIAL AND METHODS: A total of 462 girls with inguinal hernias participated in this study from January 2013 to June 2019. Laparoscopic percutaneous extraperitoneal closure of the internal ring via an epidural needle was used to treat these patients. RESULTS: All 462 girls with an inguinal hernia successfully underwent laparoscopic surgery. The operative times for unilateral and bilateral inguinal hernias were 15 (11-25) minutes and 23 (18-33) minutes, respectively. All patients were discharged 1-2 days after the operations. During the hospitalization and follow-up periods, none of the following complications were observed: hernia recurrence, umbilical hernia, abdominal wall vascular injury, intestinal injury or bladder injury. However, there were six patients with complications: two cases of poor healing of the umbilical incision, three cases of suture granulomas and one case of groin traction pain and discomfort. CONCLUSION: Laparoscopic percutaneous extraperitoneal closure of the internal ring using an epidural needle is a safe and feasible method for the treatment of inguinal hernias in girls. This method has the advantages of limited trauma, no scarring and a good cosmetic effect.

Prevalence and Population Analysis of Vibrio parahaemolyticus Isolated from Freshwater Fish in Zhejiang Province, China.

Objectives: The previous researches revealed that Vibrio parahaemolyticus has been detected in freshwater fish samples. However, the molecular characteristics of V. parahaemolyticus isolated from freshwater fish, including pathogenic and pandemic strains, are still unknown. This study aims to characterize and identify molecular properties of the bacterium. In addition, it identifies the source of V. parahaemolyticus from freshwater fish samples in Zhejiang Province, China. Methods: Four hundred and twenty-one freshwater fish samples (from fishing farms, retail markets, and restaurants) and 212 seafood samples (from retail markets) were collected in 10 cities of Zhejiang Province. V. parahaemolyticus strains were isolated from these samples and comparatively analyzed by multilocus sequence typing, serotyping, antimicrobial susceptibility test, and polymerase chain reaction, targeting common toxin genes (tdh, trh) and markers for pandemic strains (orf8, toxRS/new). Results: Sixty-eight V. parahaemolyticus strains were isolated from the 421 freshwater fish samples, and 89 V. parahaemolyticus isolates were identified out of 212 seafood samples. The detection rate of V. parahaemolyticus was significantly different (p < 0.05) between the fishing farms, the retail markets, and the restaurants. The isolates from freshwater fish samples were divided into eight O serotypes with three O3:K6 isolates, which contain three pandemic complexes (tdh+, orf8+, toxRS/new+). A total of 53 different sequence types (STs) were identified among the 68 isolates, including 28 novel STs. Antimicrobial susceptibility results indicated that 76.5% of the strains were resistant to ampicillin. A third (3/9) of the isolates from fishing farm sources shared the same STs with their counterparts from retail markets. Compared with the isolates from the seafood samples collected in the same sampling sites, 13.2% (9/68) freshwater fish isolates overlapped with seafood isolates. Conclusions: Our study showed that V. parahaemolyticus population in freshwater fish is genetically diverse. The V. parahaemolyticus contaminates might have come from both fishing farm sources and cross-contamination from seafood in the closed area at the markets. Freshwater fish may work as a reservoir of pathogenic and pandemic V. parahaemolyticus isolates, indicating potential public health and food safety risks associated with the consumption of freshwater fish.

Epidemiological and Whole Genomic Sequencing Analysis of a Campylobacter jejuni Outbreak in Zhejiang Province, China, May 2019.

Campylobacter is well recognized as the leading cause of bacterial foodborne diarrheal disease worldwide with a very low outbreak reported in China. In May 2019, we investigated an outbreak of Campylobacter jejuni infections among students in a junior high school in Eastern China. Cases were interviewed to identify a common source of contamination. As cases were identified in the same school during a period of time, menus were reviewed and food items included in the questionnaire. Rectal swabs from school kitchen staff and suspected food items (raw chicken) from a local market from where the school food came were examined for C. jejuni. Pulsed-field gel electrophoresis and whole genome sequencing were performed to determine the relatedness of the isolates. To identify the source of the contamination, a case-control study was conducted. Forty-five cases were reported with diarrhea among 1696 students and staff. Stool samples for 10 of the 45 and 5 tested positive for C. jejuni. WGS analysis revealed a 0-4 single nucleotide variation in case-patient isolates. Although we were unable to identify the specific food item, a specific menu was identified as the potential source of the contamination (odds ratios = 20.82; 95% confidence interval = 6.472-66.957). In this menu, chicken was served. A food isolate collected from chicken in Zhejiang province in 2018 was positive for the same identical strain (5-7 single nucleotide polymorphisms). This is one of the few reports in China about outbreak caused by C. jejuni. This investigation illustrates the potential risk of outbreaks caused by Chinese cold dishes of chicken.

Transscrotal transverse incision for the treatment of middle and low cryptorchidism in children: experience from 796 cases.

BACKGROUND: The purpose of this study was to summarize our clinical experience with transscrotal transverse incision in the treatment of low and middle cryptorchidism in children. METHODS: A total of 796 children with low or middle cryptorchidism participated in this study from March 2012 to May 2018. Transscrotal transverse incision was used to treat low and middle cryptorchidism. Symptoms and signs were followed up at 1 week, 1 month, 3months and every six to 12 months thereafter. RESULTS: Testicular descent fixation through transverse scrotal incision was successfully performed in all 796 children. All patients were discharged 1-2 days after the operation. During hospitalization and follow-up, 35 patients had complications, including 7 cases of cryptorchidism recurrence, 5 cases of poor scrotal incision healing, and 23 cases of scrotal haematoma. There were no complications, such as bladder injury, testicular atrophy, inguinal hernia or hydrocele. CONCLUSION: Transscrotal transverse incision is a safe and feasible method for the treatment of middle and low cryptorchidism. It has the advantages of less trauma and an aesthetic scar after operation.

Laparoscopic Disconnected Pyeloplasty to Treat Ureteropelvic Junction Obstruction (UPJO) in Children.

BACKGROUND The aim of this study was to assess the safety and clinical effectiveness of laparoscopic disconnected pyeloplasty in treating ureteropelvic junction obstruction (UPJO) in children. MATERIAL AND METHODS We retrospectively analyzed the clinical data of 122 young children with UPJO treated from February 2015 to February 2018 at our hospital. According to the surgery type, the patients were divided into 2 groups: a laparoscopic surgery group (group A, n=69) and a traditional open surgery group (group B, n=53). RESULTS The success rate of laparoscopic disconnected pyeloplasty was 100%, and none of the patients were converted to open surgery. The mean duration of use of painkillers was 27.6±11.3 h in group A and 58.2±18.2 h in group B (p=0.012), the postoperative hospital stay was 7.8±1.5 days in group A and 11.5±2.6 days in group B (p=0.041), and the length of the incision was 1.5±0.4 cm in group A and 5.2±1.1 cm in group B (p=0.007). The incidence rate of poor surgical wound healing was 0% in group A and 7.5% in group B (p=0.020). The incidence rate of ureteral stricture was 4.3% in group A and 3.8% in group B (p=0.874) during follow-up. The 1-year follow-up showed that both the anterior and posterior diameters and glomerular filtration rate were significantly improved from the preoperation period. CONCLUSIONS Laparoscopic disconnected pyeloplasty to treat UPJO in young children has the same early clinical effectiveness and safety as open surgery, and this procedure has the advantages of minimal trauma, quick recovery, and good cosmetic effect.

Early complications after laparoscopic resection of choledochal cyst.

PURPOSE: To investigate the causes and treatments of early complications involving laparoscopic radical resection of choledochal cyst and summarize the experience. METHODS: Children with choledochal cyst treated by laparoscopy in the Department of Pediatric Surgery, Fujian Provincial Maternity and Children's Hospital, and Guangzhou Women and Children's Medical Centre, from March 2016 to May 2018, were retrospectively analysed. Demographics, causes and treatments of early complications, liver function analysis and ultrasonography were collected. RESULTS: In total, 231 cases were included; 204 were Type I (156 Type Ia and 46 Type Ic) and 27 were Type IV. No mortality was observed, and 224 cases were successfully laparoscopically operated, while 7 cases were converted to open surgery. Fifteen cases of postoperative developed biliary fistula. There were jejunal Roux loop obstruction in 2 cases and multiple intussusception, anastomotic stenosis after hepaticojejunostomy, residual of choledochal cyst and pancreatic fistula in one each. Patients were followed up ranging from 4 months to 48 months (12.6 ± 0.3 months on average). Postoperative ALT, AST, GGT, TBIL and DBIL all returned to normal during this time. Ultrasonography indicated 5 cases of widened Glisson's sheath and 1 case of intrahepatic hyperdense shadow. CONCLUSION: Early complications of laparoscopic radical resection of choledochal cyst can be minimized by properly managing preoperative indications and contraindications, carefully interpreting the magnetic resonance cholangiopancreatography results and accumulating experience by the surgeons.

Multilocus sequence type profiles of Bacillus cereus isolates from infant formula in China.

Bacillus cereus sensu stricto is an opportunistic foodborne pathogen. The multilocus sequence type (MLST) of 74 B. cereus isolated from 513 non-random infant formula in China was analyzed. Of 64 sequence types (STs) detected, 50 STs and 6 alleles were newly found in PubMLST database. All isolates except for one singleton (ST-1049), were classified into 7 clonal complexes (CC) by BURST (n-4), in which CC1 with core ancestral clone ST-26 was the largest group including 86% isolates, and CC2, 3, 9, 10 and 13 were first reported in China. MLST profiles of the isolates from 8 infant formula brands were compared. It was found the brands might be potentially tracked by the variety of STs, such as ST-1049 of singleton and ST-1062 of isolate from goat milk source, though they could not be easily tracked just by clonal complex types of the isolates.

Quantitative Prevalence, Phenotypic and Genotypic Characteristics of Bacillus cereus Isolated from Retail Infant Foods in China.

Bacillus cereus is an important foodborne pathogen, which can cause severe food poisoning. The aim of this study was (i) to evaluate the quantitative prevalence of B. cereus in retail prepackaged infant formula and ready-to-eat rice flour in China and (ii) to gain the basic information on pheno- and genotypic characteristics of B. cereus isolates. We found that 40 out of the 587 samples were positive for B. cereus. B. cereus in 3.5% of infant formula samples and 1.0% of rice flour samples outnumbered 100 Colony-Forming Units (CFU)/g. B. cereus level even attained 103-104 CFU/g in four infant formula samples and one rice flour sample. Furthermore, we identified the distribution patterns of toxin genes in B. cereus isolates. The results showed that 97.5% of B. cereus isolates harbored at least one enterotoxin gene. Antibiotic susceptibility tests revealed that all isolated B. cereus strains were resistant to penicillin and 50% of them were multidrug resistant. Thirteen new sequence types (STs) and four new alleles were identified via multilocus sequence typing. Clonal Complex (CC) ST-205 and CC ST-142 were predominant clonal complexes. Interestingly, we revealed the special relationship between STs of B. cereus isolates and the geographical distributions of infant food manufacturers for the first time. The data implied that B. cereus of different STs might have a distinct ecological niche in China. In view of relatively high contamination level of enterotoxin- producing B. cereus in a proportion of infant foods, especially in those suitable for the ≤6-month-old infant group, appropriate safety criteria and hygienic control measures for infant foods should be drafted in China to prevent B. cereus infection.

Effects of functional correction training on movement patterns and physical fitness in male college students.

The objective of this study is to investigate the effects of functional corrective training and static stretching on the quality of movement patterns and physical fitness in college students. The study was conducted with 30 male college students from a university in Guangzhou, China. The participants were randomly assigned to either the functional corrective training group (FCT, n = 15, age = 20.93 ± 0.85, BMI = 22.07 ± 2.33) or the static stretching group (SS, n = 13, age = 20.85 ± 0.86, BMI = 21.98 ± 1.80). Two participants from the SS group dropped out due to personal reasons, leaving 13 subjects in that group. Both groups underwent a 6-week training intervention, with sessions held twice a week. The FCT group participated in flexibility training, and/or static motor control training, and/or dynamic motor control training for 10-15 min. The SS group performed static stretching exercises targeting five specific muscles, with 30 s per side and two sets. The Functional Movement Screen (FMS), body composition, sit-and-reach, standing long jump, and pull-ups were assessed before and after the intervention. Differences in FMS outcomes were analyzed using two samples of the Mann-Whitney U test. Physical fitness outcomes were analyzed using a repeated measures analysis of variance (ANOVA) with a 2 (group) × 2 (time) design. After 6 weeks of intervention, the FCT group showed statistically significant improvements in the hurdle step (Z = -2.449, p = 0.014), inline lunge (Z = -2.000, p = 0.046), rotary stability (Z = -2.309, p = 0.021), and composite scores (Z = -3.316, p = 0.001). Comparisons between groups indicated that BMI (FCT, ES = 0.04; SS, ES = -0.11), 30-m sprint (FCT, ES = 0.12; SS, ES = 0.28), body fat percentage (BF%) (FCT, ES = -0.25; SS, ES = -0.07), and sit-and-reach (FCT, ES = 0.17; SS, ES = 0.06) were not statistically significant in both the pre- and post-tests. The effect sizes of all physical fitness indicators were greater in the FCT group than in the SS group. The FCT, consisting of two sessions per week for 6 weeks, has been proven to be effective in improving the quality of movement patterns by improved stability and advanced movements. However, the improvements in physical fitness did not reach statistical significance. FMS and FCT are generally affordable and accessible for college students. College students have the opportunity to employ the FMS tool to assess potential injury risks and address them, thereby reducing the risk of injuries.

Isolation and characterization of Chlamydia felis and its pathogenesis in cats.

Feline upper respiratory tract disease (URTD) is a common but complicated disease that occurs in domestic cats, worldwide. 396 cats in Guangxi Province, China were screened for URTD-associated pathogens from March 2022 to August 2023. Mycoplasma felis was found to be the most prevalent infectious agent with a positivity rate of 24.75 %, followed by feline calicivirus (FCV), Chlamydia felis, feline herpesvirus 1 (FHV-1) and feline influenza A virus (FeIAV) with rates of 15.91, 11.62, 5.56 and 1.52 %, respectively. In particular, C. felis and M. felis were found in 13 of 55 co-infected cats. Of the 46 C. felis-positive samples, one strain, named as GXNN36, was successfully isolated using chicken embryos and it was characterized both in vivo and in vitro. For the cat studies, both high- and low-dose challenged groups showed severe conjunctivitis, accompanied by transient fever and respiratory symptoms. C. felis replicated well in turbinate, trachea and lung tissues with high copy numbers and the infection subsequently spread to the livers, spleens, pancreas, kidneys, hearts and intestines. These findings will help our understanding of the role of C. felis in feline URTD and provide a valuable model to evaluate the efficacy of vaccines and therapeutic remedies in the future.

Age-effects of sport education model on basic psychological needs and intrinsic motivation of adolescent students: A systematic review and meta-analysis.

OBJECTIVE: This study explores the age effects of the sport education model(SEM) on the impact of basic psychological needs (autonomy, competence, relatedness) and intrinsic motivation (interest, enjoyment, satisfaction) among adolescent students. METHOD: Retrieval of relevant literature from PubMed, Web of Science, Scopus, and China National Knowledge Infrastructure (CNKI). The search period ranged from the starting year to January 7, 2024. Subsequently, literature screening, data extraction, and quality assessment will be conducted, and data analysis will be performed using "Review Manager 5.4" software. RESULT: Overall, SEM has a positive and statistically significant impact on the basic psychological needs (MD = 0.36,95% CI [0.22, 0.50]) and intrinsic motivation (MD = 0.75, 95% CI [0.58, 0.93]) of adolescent students (P<0.01). Subgroup analysis revealed age effects on the impact of SEM on the basic psychological needs of adolescent students: pre-peak height velocity (PRE-PHV) (MD = 0.39, 95% CI [0.23, 0.56], I2 = 45%, P<0.01), mid-peak height velocity (MID-PHV) (MD = 0.22, 95% CI [0.01, 0.42], I2 = 82%, P<0.05), post-peak height velocity (POST-PHV) (MD = 1.27, 95% CI [0.79, 1.74], I2 = 0%, P<0.01). Similarly, age effects were found for intrinsic motivation: MID-PHV (MD = 0.86, 95% CI [0.62, 1.11], I2 = 68%, P<0.01), POST-PHV (MD = 0.56, 95% CI [0.40, 0.72], I2 = 0%, P<0.01). CONCLUSION: The SEM is an effective approach to enhancing the basic psychological needs and intrinsic motivation of adolescent students. However, it exhibits age effects among students at different developmental stages. Specifically, in terms of enhancing basic psychological needs, the model has the greatest impact on POST-PHV students, followed by PRE-PHV students, while the improvement effect is relatively lower for MID-PHV students. The enhancement effect on intrinsic motivation diminishes with increasing age.

Synergistic HA and NS mutations enhanced the virulence of a mouse-adapted H1N1 influenza A virus.

H1N1 reassortants between the swine Eurasian avian-like (EA) and H1N1 2009 pandemic (H1N1 pdm/09) viruses have been circulating stably in pig populations for more than ten years, and they may have contributed to increased human infections. Whether these H1N1 viruses acquire adaptive mutations to increase their pathogenicity towards a new host is unknown. To address this problem, mouse-adapted (MA) variants of swine-origin EA H1N1 influenza virus isolated from dogs (A/canine/Guangxi/LZ57/2015[LZ57-MA]) were generated by serial lung-to-lung passages in BALB/c mice. These exhibited greater virulence and replication capability than the wild-type virus (LZ57-WT). Of the six adaptive mutations, two were mapped to the ribonucleoprotein (RNP) complex (PB2-E578D and PA-T97I), two to hemagglutinin (HA-N198D and HA-A227E) and two to the non-structural protein 1 (NS1) and nuclear export protein (NS1-A53D and NEP-R42K, respectively). Reverse genetic substitution of the viral genes and mutation experiments demonstrated that the mutations in PA-T97I could enhance the polymerase activity, but a significant downregulation of activity was seen with PB2-E578D, which was consistent with a decrease in virulence. However, HA and NS, which are genes that act synergistically, were found to be determinants of virulence in mice. The reassortant viruses bearing HA mutations (N198D and A227E) were acquired during adaptation enhanced early-stage viral replication in mammalian cells. The single-point mutations in the NS genes had limited effects on virulence. Furthermore, a combination of HA (N198D and A227E) with NS(A53D) in the rLZ57-WT backbone resulted in efficient replication and a significant increase in virulence. The results suggest that these substitutions could compensate for the polymerase function and contribute to enhanced virulence, which highlights a major role for mutations in the HA and NS genes.

Prevalence and antimicrobial-resistant characterization of Bacillus cereus isolated from ready-to-eat rice products in Eastern China.

Bacillus cereus is a major food-borne bacterial pathogen in the world, which can cause diarrhea and emetic syndrome. This study aimed to reveal the quantitative prevalence of B. cereus in ready-to-eat (RTE) rice products in Eastern China and to gain essential information on the characteristics of B. cereus isolates. A total of 91 out of the 1071 samples were positive for B. cereus. The contamination level of B. cereus in 0.5 % of RTE rice product samples outnumbered 103 CFU/g. The number of B. cereus attained 105-106 CFU/g in one sample. The distribution patterns of virulence genes in B. cereus isolates were identified. 84.6% of the B. cereus isolates had at least one enterotoxin or emetic toxin gene. The predominant pattern was XXV. 9.9% of isolates belonged to it and possessed one enterotoxin gene entFM. The occurrence rate of hblACD and nheABC was 36.3% and 47.3%, respectively. Antimicrobial susceptibility tests revealed a high resistance rate toward penicillin, and 23.1% of the isolates were multi-drug resistant. B. cereus isolates were genotyped by using ERIC-PCR. 89 genotypes were determined. The Hunter Gaston Discriminatory Index (HGDI) attained 0.9995. Relationships analysis revealed that Group A B. cereus isolates tended to carry hblA, hblC, hblD, nheA, nheB, and show resistance to penicillin/trimethoprim/sulfamethoxazole. This study was useful for updating the knowledge of the contamination status of B. cereus in RTE rice products in China.

Antimicrobial resistance and genomic investigation of non-typhoidal Salmonella isolated from outpatients in Shaoxing city, China.

Human non-typhoidal salmonellosis is among the leading cause of morbidity and mortality worldwide, resulting in huge economic losses and threatening the public health systems. To date, epidemiological characteristics of non-typhoidal Salmonella (NTS) implicated in human salmonellosis in China are still obscure. Herein, we investigate the antimicrobial resistance and genomic features of NTS isolated from outpatients in Shaoxing city in 2020. Eighty-seven Salmonella isolates were recovered and tested against 28 different antimicrobial agents, representing 12 categories. The results showed high resistance to cefazolin (86.21%), streptomycin (81.61%), ampicillin (77.01%), ampicillin-sulbactam (74.71%), doxycycline (72.41%), tetracycline (71.26%), and levofloxacin (70.11%). Moreover, 83.91% of isolates were resistant to ≥3 categories, which were considered multi-drug resistant (MDR). Whole-genome sequencing (WGS) combined with bioinformatic analysis was used to predict serovars, MLST types, plasmid replicons, antimicrobial resistance genes, and virulence genes, in addition to the construction of phylogenomic to determine the epidemiological relatedness between isolates. Fifteen serovars and 16 STs were identified, with the dominance of S. I 4, [5], 12:i:- ST34 (25.29%), S. Enteritidis ST11 (22.99%), and S. Typhimurium ST19. Additionally, 50 resistance genes representing ten categories were detected with a high prevalence of aac(6')-Iaa (100%), bla TEM-1B (65.52%), and tet(A) (52.87%), encoding resistance to aminoglycosides, ß-lactams, and tetracyclines, respectively; in addition to chromosomic mutations affecting gyrA gene. Moreover, we showed the detection of 18 different plasmids with the dominance of IncFIB(S) and IncFII(S) (39.08%). Interestingly, all isolates harbor the typical virulence genes implicated in the virulence mechanisms of Salmonella, while one isolate of S. Jangwani contains the cdtB gene encoding typhoid toxin production. Furthermore, the phylogenomic analysis showed that all isolates of the same serovar are very close to each other and clustered together in the same clade. Together, we showed a high incidence of MDR among the studied isolates which is alarming for public health services and is a major threat to the currently available treatments to deal with human salmonellosis; hence, efforts should be gathered to further introduce WGS in routinely monitoring of AMR Salmonella in the medical field in order to enhance the effectiveness of surveillance systems and to limit the spread of MDR clones.

Co-circulation and evolution of genogroups I and II of respiratory and enteric feline calicivirus isolates in cats.

Feline calicivirus (FCV) is a highly infectious pathogen that causes upper respiratory tract disease (URTD), but the enteric FCVs raise concerns regarding their role of an enteric pathogen. In this study, between 2019 and 2020, 101 clinical samples from domestic cats with symptoms of URTD, with or without enteritis, were collected for FCV-specific detection. The FCV-positive rate reached to 42.4% (28/66) in cats with respiratory symptoms. The rates were 11.1% (3/27) and 12.5% (1/8) when faeces and serum samples were measured using reverse transcription polymerase chain reaction (RT-PCR), respectively. Ten FCV strains were successfully isolated from respiratory and enteric sources in domestic cats from Guangxi. Phylogenetic analysis based on the genome sequences of 11 isolates (including GX01-13 isolated in 2013) indicated that the newly characterized FCV strains had two recombinant events in comparison with other FCVs and were of respiratory and enteric origins. These strains displayed high genetic diversity, and they were divided into two genogroups (I and II). Of these, the GXNN02-19 isolate was grouped with previously published Chinese isolates that were identified as genogroup II, which contained three specific amino acid residues (377K, 539V and 557S) in the VP1 protein. In addition, the three enteric viruses appeared genetically heterogeneous to each other. All isolates were found to be more sensitive when exposed to low pH conditions, but they were resistant to treatment with trypsin and bile salts. Furthermore, there were no significant differences between the respiratory and enteric FCVs. Our results showed that the genetically distinct FCV strains with genogroups I and II from respiratory and enteric origins were co-circulating in this geographical area. Also, it was revealed that the potential recombinant events between the enteric and respiratory FCVs suggested an important role of enteric FCV during the evolution.

Novel machine learning models to predict pneumonia events in supratentorial intracerebral hemorrhage populations: An analysis of the Risa-MIS-ICH study.

Background: Stroke-associated pneumonia (SAP) contributes to high mortality rates in spontaneous intracerebral hemorrhage (sICH) populations. Accurate prediction and early intervention of SAP are associated with prognosis. None of the previously developed predictive scoring systems are widely accepted. We aimed to derive and validate novel supervised machine learning (ML) models to predict SAP events in supratentorial sICH populations. Methods: The data of eligible supratentorial sICH individuals were extracted from the Risa-MIS-ICH database and split into training, internal validation, and external validation datasets. The primary outcome was SAP during hospitalization. Univariate and multivariate analyses were used for variable filtering, and logistic regression (LR), Gaussian naïve Bayes (GNB), random forest (RF), K-nearest neighbor (KNN), support vector machine (SVM), extreme gradient boosting (XGB), and ensemble soft voting model (ESVM) were adopted for ML model derivations. The accuracy, sensitivity, specificity, and area under the curve (AUC) were adopted to evaluate the predictive value of each model with internal/cross-/external validations. Results: A total of 468 individuals with sICH were included in this work. Six independent variables [nasogastric feeding, airway support, unconscious onset, surgery for external ventricular drainage (EVD), larger sICH volume, and intensive care unit (ICU) stay] for SAP were identified and selected for ML prediction model derivations and validations. The internal and cross-validations revealed the superior and robust performance of the GNB model with the highest AUC value (0.861, 95% CI: 0.793-0.930), while the LR model had the highest AUC value (0.867, 95% CI: 0.812-0.923) in external validation. The ESVM method combining the other six methods had moderate but robust abilities in both cross-validation and external validation and achieved an AUC of 0.843 (95% CI: 0.784-0.902) in external validation. Conclusion: The ML models could effectively predict SAP in sICH populations, and our novel ensemble model demonstrated reliable robust performance outcomes despite the populational and algorithmic differences. This attempt indicated that ML application may benefit in the early identification of SAP.

A SARS-CoV-2 variant with the 12-bp deletion at E gene.

The coronavirus disease 2019 (COVID-19) pandemic is still ongoing and has become an important public health threat. This disease is caused by a new coronavirus named severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection, and so far, little is known about this virus. In this study, by using plaque purification, we purified two SARS-CoV-2 virus strains from the same specimen, one named F8 containing a 12-bp deletion in the E gene and the other named 8X containing the wild-type E gene. There was no significant difference in the viral titer and infectivity of these two strains. The S protein content of the F8 viral culture was 0.39 µg/ml, much higher than that of 8X. An inactivated vaccine made from the F8 strain could trigger high levels of the IgG titer and neutralizing antibody titer, which could last for at least 6 weeks and were significantly higher than those from the 8X strain at 1 and 3 weeks post vaccination, respectively. In conclusion, we reported that both the E gene mutant and wild-type SARS-CoV-2 strains were isolated from the same clinical sample by plaque purification. A 12-bp deletion in the E gene was important for SARS-CoV-2 replication and immunogenicity.

Prevalence, Genotypic Characteristics and Antibiotic Resistance of Listeria monocytogenes From Retail Foods in Bulk in Zhejiang Province, China.

Listeria monocytogenes is an important foodborne pathogen causing public concern. A total of 3354 retail foods in bulk were sampled and screened for L. monocytogenes. Seventy-three (2.2%) samples including 21 ready-to-eat (RTE) foods and 52 raw foods were confirmed positive for L. monocytogenes. Sushi and salmon sashimi occupied the top two slots in RTE foods with relatively high presence rate of 12.9 and 6.9%, respectively. Meanwhile, L. monocytogenes was found to be distributed unequally in raw foods; the presence rates in raw meat (3.5%) and poultry (3.8%) were significantly higher than that in raw seafood (1.3%). Notably, L. monocytogenes was not detected in raw freshwater food. The L. monocytogenes isolates belonged to four serotypes, 1/2a, 1/2b, 1/2c, and 4b, with the most prevalent serotype being 1/2a (47.9%). Eighteen sequence types (STs) and eighteen virulence types (VTs) containing four newly assigned VTs (VT180, VT181, VT182, and VT183) were determined via multilocus sequence typing (MLST) and multi-virulence-locus sequence typing (MVLST). Among the 73 L. monocytogenes isolates, 23 (31.5%) belonged to epidemic clones (ECs) including ECI, ECIV, ECV, ECVI, ECVIII and ECXI among which ECV was predominant. Antibiotic susceptibility tests revealed a high resistance rate (11.0%) to tetracycline. Moreover, we identified the distribution patterns of virulence genes of four Listeria pathogenicity islands (LIPI) in L. monocytogenes isolates. prfA, hly, plcA, plcB, mpl, actA genes in LIPI-1 and inlA, inlB, inlC, inlJ genes in LIPI-2 were detected in approximately all L. monocytogenes isolates. The distribution of both LIPI-3 genes and LIPI-4 genes exhibited association with lineage and ST. LIPI-4 genes were present exclusively in ST87 isolates. Relatedness analysis revealed the absence of distinct association between STs, ECs, LIPI-3 and LIPI-4 distribution and specific food groups. This study provided fundamental data for Chinese food safety authorities to grasp the contamination status of L. monocytogenes in foods, assess the potential risk of this pathogen and further address the safety issue of retail foods in bulk in China.