This study explored the antibiotic resistance and resistance gene carriage of 140 Salmonella strains isolated from environmental sewage in Guangzhou city between March 1,2022,and November 30,2022.The micro broth dilution method was used to select 17 antibiotics for susceptibility testing.According to whole genome sequencing results,the CARD resistance database was used to obtain corresponding resistance genes.High antimicrobial resistance rates above 80％were observed a-gainst ampicillin,tetracycline,streptomycin,chloramphenicol,and cotrimoxazole.The intermediation rate of polymyxin E and ciprofloxacin exceeded 60％.The multiple drug resistance status was severe,and the rate of multiple drug resistance was as high as 92.86％.The strains carried multiple types of resistance genes,particularly for aminoglycosides,with a carriage rate as high as 92.68％.The resistance of Salmonella in environmental wastewater in Guangzhou to one or more drugs was severe,and the overall multi-drug resistance rate gradually increased over time.The resistance spectrum was diverse,and the resistance mechanism,mediated by mobile genetic elements such as re-sistance genes,was found to be the main cause of resistance to one or more drugs.

The regulatory requirements of 3D printing products were introduced.The risks during the production of 3D printed navigational template for orthopedic surgery were summarized in terms of data acquisition,medical-industrial intera-ction design,3D printing,post-processing and sterilization.Some quality control measures were proposed from the aspects of quality control of raw materials,validation of data and software,verification of printing process parameters,post-processing method and verification,sterilization verification and testing of semi-finished and final products,so as to enhance the safety and effectiveness of 3D printed navigational template for orthopedic surgery.[Chinese Medical Equipment Journal,2024,45(5):80-85]

Glyceryl phenylbutyrate(GPB)serves as a long-term management medication for Ornithine transcarbamylase deficiency(OTCD),effectively controlling hyperammonemia,but there is a lack of experience in using this medicine in China.This article retrospectively analyzes the case of a child diagnosed with OTCD at Shanghai Children's Medical Center,Shanghai Jiao Tong University School of Medicine,including a review of related literature.After diagnosis,the patient was treated with GPB,followed by efficacy follow-up and pharmacological monitoring.The 6-year and 6-month-old male patient exhibited poor speech development,disobedience,temper tantrums,and aggressive behavior.Blood ammonia levels peaked at 327 μmol/L;urine organic acid analysis indicated elevated uracil levels;cranial MRI showed extensive abnormal signals in both cerebral hemispheres.Genetic testing revealed de novo mutation in the OTC gene(c.241T＞C,p.S81P).Blood ammonia levels were approximately 43,80,and 56 μmol/L at 1,2,and 3 months after starting GPB treatment,respectively.During treatment,blood ammonia was well-controlled without drug-related adverse effects.The patient showed improvement in developmental delays,obedience,temperament,and absence of aggressive behavior.

Objective To observe the effects of melatonin on autophagy in cortical neurons of neonatal rats with hypoxic-ischemic brain damage(HIBD)and to explore its mechanisms via the PI3K/AKT signaling pathway,aiming to provide a basis for the clinical application of melatonin.Methods Seven-day-old Sprague-Dawley neonatal rats were randomly divided into a sham operation group,an HIBD group,and a melatonin group(n=9 each).The neonatal rat HIBD model was established using the classic Rice-Vannucci method.Neuronal morphology in the neonatal rat cerebral cortex was observed with hematoxylin-eosin staining and Nissl staining.Autophagy-related protein levels of microtubule-associated protein 1 light chain 3(LC3)and Beclin-1 were detected by immunofluorescence staining and Western blot analysis.Phosphorylated phosphoinositide 3-kinase(p-PI3K)and phosphorylated protein kinase B(p-AKT)protein expression levels were measured by immunohistochemistry and Western blot.The correlation between autophagy and the PI3K pathway in the melatonin group and the HIBD group was analyzed using Pearson correlation analysis.Results Twenty-four hours post-modeling,neurons in the sham operation group displayed normal size and orderly arrangement.In contrast,neurons in the HIBD group showed swelling and disorderly arrangement,while those in the melatonin group had relatively normal morphology and more orderly arrangement.Nissl bodies were normal in the sham operation group but distorted in the HIBD group;however,they remained relatively intact in the melatonin group.The average fluorescence intensity of LC3 and Beclin-1 was higher in the HIBD group compared to the sham operation group,but was reduced in the melatonin group compared to the HIBD group(P<0.05).The number of p-PI3K+and p-AKT+cells decreased in the HIBD group compared to the sham operation group but increased in the melatonin group compared to the HIBD group(P<0.05).LC3 and Beclin-1 protein expression levels were higher,and p-PI3K and p-AKT levels were lower in the HIBD group compared to the sham operation group(P<0.05);however,in the melatonin group,LC3 and Beclin-1 levels decreased,and p-PI3K and p-AKT increased compared to the HIBD group(P<0.05).The correlation analysis results showed that the difference of the mean fluorescence intensity of LC3 and Beclin-1 protein in the injured cerebral cortex between the melatonin and HIBD groups was negatively correlated with the difference of the number of p-PI3K+and p-AKT+cells between the two groups(P<0.05).Conclusions Melatonin can inhibit excessive autophagy in cortical neurons of neonatal rats with HIBD,thereby alleviating HIBD.This mechanism is associated with the PI3K/AKT pathway.

Acute liver injury (ALI) is one of the common severe diseases in clinic, which is characterized by redox imbalance and inflammatory storm. Untimely treatment can easily lead to liver failure and even death. Rosmarinic acid (RA) has been proved to have anti-inflammatory and antioxidant activity, but it is not clear how to protect ALI through antioxidation and inhibition of inflammation. Therefore, this study explored the therapeutic effect and molecular mechanism of RA on ALI through in vitro and in vivo experiments. In the mouse ALI model, the effects of RA on liver function and inflammatory indexes were studied, the pathological changes of liver were observed by HE, the effect of RA on reactive oxygen species in liver was detected by fluorescence method, and the level of F4/80 in liver tissue was detected by immunohistochemical method. The levels of thioredoxin interacting protein (TXNIP), NOD-like receptor protein 3 (NLRP3) and cysteinyl aspartate specific proteinase-1 (CASPASE-1) in liver tissue were measured by Western blot. All animal welfare and experimental procedures follow the rules of the Animal Ethics Committee of Southwest Minzu University. In vitro, human hepatoma cell line HepG2 was used to establish the model of oxidative damage induced by H₂O₂. The cell viability was detected by CCK-8 method. The level of interleukin-1β (IL-1β) in the supernatant was detected by enzyme linked immunosorbent assay (ELISA), the activity of lactatede hydrogenase (LDH) was detected by LDH kit, and the level of ROS was detected by fluorescence probe DCFH-DA labeling. The mRNA expression of Txnip, Nlrp3, Caspase 1, Il1β was detected by real-time fluorescence quantitative PCR (qPCR), and the protein levels of nuclear factor erythroid-2 related factor 2 (NRF2), TXNIP, NLRP3 and CASPASE-1 were measured by Western blot. The results showed that compared with the model group, the degree of liver swelling, tissue injury, liver function index in RA group were significantly lower than those in model group. And RA significantly attenuated the increases of ROS in liver tissue. The expression levels of TXNIP, NLRP3 and CASPASE-1 in liver tissue were significantly lower than those in model group. Additionally, RA inhibited the expressions of F4/80 and IL-1β. In vitro experiment, compared with model group, RA effectively inhibited the secretion of IL-1β and LDH. The level of ROS also decreased significantly. RA inhibited the mRNA expressions of Txnip, Caspase 1, Il1β. Furthermore, RA significantly increased the expression level of NRF2 protein in nucleus, and decreased the expression level of TXNIP and NLRP3 protein. Specifically, with the addition of ML385, the effect of RA on NRF2, TXNIP, NLRP3, CASPASE-1 protein expression was reversed. Collectively, these findings suggested that RA may inhibit the production of ROS by promoting NRF2 nuclear transfer, and then reduce the activation of NLRP3 inflammatory bodies by TXNIP, reduce cell death and inflammatory response to prevent the liver injury.

Based on the genomic information of Emericella sp. 1454, in conjunction with literature analysis of its secondary metabolite emestrin, this study identified the biosynthetic precursors of emestrin and enhanced its production by supplementing the culture medium with these precursors. In this study, it was found for the first time that the addition of biosynthetic precursor, reduced glutathione, to the culture medium significantly increased emestrin yield. By incorporating 1.5 g of reduced glutathione into 50 g of rice culture medium and fermenting for 15 days, a yield of 30.82 mg of emestrin was obtained, which marked an 11.71-fold increase compared to the original fermentation approach. The method is both simple and cost-effective, establishing a solid foundation for the efficient synthesis of emestrin and similar compounds. Additionally, it serves as an important reference for enhancing the production of other epipolythiodioxopiperazine compounds.

Objective This study aimed to understand the epidemic status and phylogenetic relationships of rotavirus group A(RVA)in the Pearl River Delta region of Guangdong Province,China. Methods This study included individuals aged 28 days-85 years.A total of 706 stool samples from patients with acute gastroenteritis collected between January 2019 and January 2020 were analyzed for 17 causative pathogens,including RVA,using a Gastrointestinal Pathogen Panel,followed by genotyping,virus isolation,and complete sequencing to assess the genetic diversity of RVA. Results The overall RVA infection rate was 14.59%(103/706),with an irregular epidemiological pattern.The proportion of co-infection with RVA and other pathogens was 39.81%(41/103).Acute gastroenteritis is highly prevalent in young children aged 0-1 year,and RVA is the key pathogen circulating in patients 6-10 months of age with diarrhea.G9P[8](58.25%,60/103)was found to be the predominant genotype in the RVA strains,and the 41 RVA-positive strains that were successfully sequenced belonged to three different RVA genotypes in the phylogenetic analysis.Recombination analysis showed that gene reassortment events,selection pressure,codon usage bias,gene polymorphism,and post-translational modifications(PTMs)occurred in the G9P[8]and G3P[8]strains. Conclusion This study provides molecular evidence of RVA prevalence in the Pearl River Delta region of China,further enriching the existing information on its genetics and evolutionary characteristics and suggesting the emergence of genetic diversity.Strengthening the surveillance of genotypic changes and gene reassortment in RVA strains is essential for further research and a better understanding of strain variations for further vaccine development.

Objective: To understand the current situation and trends of anemia among kindergarten children in urban area of Suzhou from 2018 to 2022, so as to provide a theoretical basis for prevention and intervention in anemia among kindergarten children. Methods: From March 2023, a total of 24 178 person times of children from 59 kindergartens selected by random number table method were enrolled, and their physical examination data from 2018 to 2022 were collected, including hemoglobin (Hb), height, gender, weight. The period of 2018-2019 was defined as before the COVID-19 epidemic, and period of 2020-2022 was defined as the COVID-19 epidemic. Data were analyzed using the Mann Whitney U test, χ 2 test and Spearman s correlation analysis. Results: From 2018 to 2019, the M ( P 25 ， P 75 ) of Hb levels of children in nursery, middle, and senior class were 118 (112, 129), 120 (112, 132) and 122 (113, 134)g/L, respectively, which were higher than that of during 2020-2022 [116(110, 123), 117(111, 124) , 119(112, 126)g/L, Z =-10.7, -12.7, -12.9, P <0.05]. A total of 4 584 person times of children were anemic, with a detection rate of 19.0%. The overall anemia detection rate of kindergarten children during 2018-2019 was lower than that in 2020-2022 (15.3% vs 20.7%, χ 2=100.8, P <0.05). The anemia detection rate of kindergarten children in 2022 (24.5%) was higher than that in 2020 (20.6%) and in 2021 (17.0%) ( χ 2=93.9, P <0.05). The anemia prevalence of children in the nursery, middle, and senior class were 13.9%, 14.7% and 17.1% during 2018-2019, 19.3%, 15.9% and 26.6% during 2020-2022, and 17.6%, 15.5% and 23.6% during 2018-2022, respectively ( χ 2=10.7, 204.6, 186.8, P <0.01). There was no statistically significant correlation between Hb values and body mass index (BMI) in boys and girls with anemia, and all children in kindergarten ( r=0.03, 0.03, 0.09, P ＞0.05). Conclusion The prevalence of anemia among kindergarten children in the urban area of Suzhou is relatively high. The COVID-19 pandemic may have increased the risk of anemia among children.

OBJECTIVES: To investigate the risk factors for neonatal asphyxia in Hubei Enshi Tujia and Miao Autonomous Prefecture and establish a nomogram model for predicting the risk of neonatal asphyxia. METHODS: A retrospective study was conducted with 613 cases of neonatal asphyxia treated in 20 cooperative hospitals in Enshi Tujia and Miao Autonomous Prefecture from January to December 2019 as the asphyxia group, and 988 randomly selected non-asphyxia neonates born and admitted to the neonatology department of these hospitals during the same period as the control group. Univariate and multivariate analyses were used to identify risk factors for neonatal asphyxia. R software (4.2.2) was used to establish a nomogram model. Receiver operator characteristic curve, calibration curve, and decision curve analysis were used to assess the discrimination, calibration, and clinical usefulness of the model for predicting the risk of neonatal asphyxia, respectively. RESULTS: Multivariate logistic regression analysis showed that minority (Tujia), male sex, premature birth, congenital malformations, abnormal fetal position, intrauterine distress, maternal occupation as a farmer, education level below high school, fewer than 9 prenatal check-ups, threatened abortion, abnormal umbilical cord, abnormal amniotic fluid, placenta previa, abruptio placentae, emergency caesarean section, and assisted delivery were independent risk factors for neonatal asphyxia (P<0.05). The area under the curve of the model for predicting the risk of neonatal asphyxia based on these risk factors was 0.748 (95%CI: 0.723-0.772). The calibration curve indicated high accuracy of the model for predicting the risk of neonatal asphyxia. The decision curve analysis showed that the model could provide a higher net benefit for neonates at risk of asphyxia. CONCLUSIONS The risk factors for neonatal asphyxia in Hubei Enshi Tujia and Miao Autonomous Prefecture are multifactorial, and the nomogram model based on these factors has good value in predicting the risk of neonatal asphyxia, which can help clinicians identify neonates at high risk of asphyxia early, and reduce the incidence of neonatal asphyxia.
Infant, Newborn ; Humans ; Male ; Pregnancy ; Female ; Nomograms ; Retrospective Studies ; Cesarean Section ; Risk Factors ; Asphyxia Neonatorum/etiology*

OBJECTIVES: To explore the association between assisted reproductive technology (ART) and birth weight discordance in twins (BWDT). METHODS: A retrospective analysis was conducted on twin infants born between January 2011 and December 2020 at the Third Affiliated Hospital of Guangzhou Medical University, with complete basic birth data. The impact of ART on the occurrence of BWDT was identified by the multivariate logistic regression analysis. RESULTS: A total of 3 974 pairs of twins were included, with 1 431 conceived naturally and 2 543 through ART. Neonates in the ART group had higher birth weights than those in the naturally conceived group (P<0.001). The incidence of BWDT was lower in the ART group compared to the naturally conceived group (16.17% vs 21.09%, P<0.001). The multivariate logistic regression analysis, adjusting for confounding factors such as maternal age, parity, pre-pregnancy body mass index, gestational diabetes, hypothyroidism, gestational age, and chorionic properties, showed no significant difference in the risk of BWDT between the ART and naturally conceived groups (P>0.05). CONCLUSIONS ART is not associated with the risk of BWDT.
Pregnancy ; Infant, Newborn ; Female ; Humans ; Birth Weight ; Pregnancy Outcome ; Infant, Premature ; Infant, Low Birth Weight ; Pregnancy, Multiple ; Premature Birth/epidemiology* ; Retrospective Studies ; Population Surveillance ; Reproductive Techniques, Assisted/adverse effects* ; Pregnancy Complications