This study was aimed at identifying the pathogenic bacteria responsible for the death of a young tiger at the Fujian Meihua Mountain South China Tiger Breeding Research Institute.Tissue samples from the lungs,liver,and intestines of the deceased tiger were collected,and the bacteria were cultured inasterile environment.The bacterial strains were characterized according to their morphological and molecular biological properties,including assessment of virulence genes and antibiotic resistance genes,mouse lethality tests,and antibiotic susceptibility evaluations.A predominant bacterial strain isolated from the liver of the deceased tiger was identified as enterotoxigenic Escherichia coli(ETEC)strain Tiger22513F.Phylogenetic analysis of the 16S rRNA gene revealed that the Tiger22513F strain exhibited close genetic similarity to the reference strain ETEC(MF919609.1),with 99.9%nucleotide similarity,and resided on the same evolutionary branch.The Tiger22513F strain contained 11 antibiotic resistance genes(tetA,sul1,sul3,cmlA,floR,blaTEM,blaSHV,blaCMY-2,qnrA,qnrS,and qnrD)along with five virulence genes(VT1,fyuA,tsh,iucD,and ST).Mouse lethality tests indicated significant pathogenicity toward mice,affecting primarily the lungs,liver,and intestines.Antibiotic susceptibility testing demonstrated that this strain exhibited resistance to various classes of beta-lactam antibiotics,as well as quinolones and aminoglycosides.This investigation successfully isolated a multi-drug resistant enterotoxigenic Escherichia coli strain with pronounced pathogenicity from the liver of a deceased tiger;thus providing valuable scientific insights for clinical diagnosis,as well as prevention and control measures,against ETEC infections in South China tigers.

The phase changes and quantity-quality transfer of 17 batches of Ostreae Concha(Ostrea rivularis) during the raw material-calcined decoction pieces-standard decoction process were analyzed. The content of calcium carbonate(CaCO_3), the main component, was determined by chemical titration, and the extract yield and transfer rate were calculated. The CaCO_3 content in the raw material, calcined decoction pieces, and standard decoction was 94.39%-98.80%, 95.03%-99.22%, and 84.58%-90.47%, respectively. The process of raw material to calcined decoction pieces showed the yield range of 96.85% to 98.55% and the CaCO_3 transfer rate range of 96.92% to 99.27%. The process of calcined decoction pieces to standard decoction showed the extract yield range of 2.86% to 5.48% and the CaCO_3 transfer rate range of 2.59% to 5.13%. The results of X-ray fluorescence(XRF) assay showed that the raw material, calcined decoction pieces, and standard decoction mainly contained Ca, Na, Mg, Si, Br, Cl, Al, Fe, Cr, Mn, and K. The chemometric results showed an increase in the relative content of Cr, Fe, and Si from raw material to calcined decoction pieces and an increase in the relative content of Mg, Al, Br, K, Cl, and Na from calcined decoction pieces to standard decoction. X-ray diffraction(XRD) was employed to establish XRD characteristic patterns of the raw material, calcined decoction pieces, and standard decoction. The XRD results showed that the main phase of all three was calcite, and no transformation of crystalline form or generation of new phase was observed. Fourier transform infrared spectroscopy(FTIR) was employed to establish the FTIR characteristic spectra of the raw material, calcined decoction pieces, and standard decoction. The FTIR results showed that the raw material had internal vibrations of O-H, C-H, C=O, C-O, and CO■ groups. Due to the loss of organic matter components after calcination, no information about the vibrations of C-H, C=O, and C-O groups was observed in the spectra of calcined decoction pieces and standard decoction. In summary, this study elucidated the quantity-quality transfer and phase changes in the raw material-calcined decoction pieces-standard decoction process by determining the CaCO_3 content, calculating the extract yield and transfer rate, and comparing the element changes, FTIR characteristic spectra, and XRD characteristic pattern. The results were reasonable and reliable, laying a foundation for the subsequent process research and quality control of the formula granules of calcined Ostreae Concha(O. rivularis Gould), and providing ideas and methods for the quality control of the whole process of raw material-decoction pieces-standard decoction-formula granules of Ostreae Concha and other testacean traditional Chinese medicine.
Drugs, Chinese Herbal/isolation & purification* ; Calcium Carbonate/analysis* ; Quality Control

This study investigated the potential pathogenicity and genetic characteristics of ST314 Salmonella Kentucky(S.Ken-tucky)isolates from a broiler slaughterhouse.Antimicrobial susceptibility testing and whole-genome sequencing(WGS)were used to determine antimicrobial resistance,virulence factors,and the presence of antimicrobial resistance genes(ARGs)and mobile genetic elements(MGEs)among the isolates.The three multidrug resistant(MDR)isolates exhibited high resistance to multiple antimicrobial agents.The F4-2S strain exhibited resistance to 14 drugs across seven categories,whereas the F4T strain showed resistance to 13 drugs in the same number of categories.In contrast,the Y23 strain was resistant to nine drugs in six categories.Notably,F4-2S dem-onstrated high homology with F4T:both possessed 13 ARGs distributed across nine categories,in addition to a wide range of virulence factors,including secretion systems and effector proteins.The presence of IncR and IncX1 plasmids significantly enhanced both the antimicrobial resistance and pathogenicity of the isolates.The genome map of Y23 revealed a chromosome alongside two plasmids.The chromosome containedonly one resistance gene but several virulence factors,including the type III secretion system(T3SS),which is crucial for bacterial invasion.The plasmid pY23-1 contained eight types of 19 ARGs.Comparative analysis indicated that pY23-1 ex-hibited high homology with pZ1323SSL0055 and pSAL-045,all of which contained multiple ARGs,thus suggesting critical roles of these genes in the evolution of bacterial resistance.In conclusion,ST314 S.Kentucky demonstrated a complex mechanism of resis-tance coupled with significant pathogenic potential.The ARGs and MGEs in the plasmid contributed to the emergence and dissemina-tion of antimicrobial resistance.The multiple virulence factors present in the chromosome may be key factors driving the increasing virulence of ST314 S.Kentucky.

This study was aimed at identifying the pathogenic bacteria responsible for the death of a young tiger at the Fujian Meihua Mountain South China Tiger Breeding Research Institute.Tissue samples from the lungs,liver,and intestines of the deceased tiger were collected,and the bacteria were cultured inasterile environment.The bacterial strains were characterized according to their morphological and molecular biological properties,including assessment of virulence genes and antibiotic resistance genes,mouse lethality tests,and antibiotic susceptibility evaluations.A predominant bacterial strain isolated from the liver of the deceased tiger was identified as enterotoxigenic Escherichia coli(ETEC)strain Tiger22513F.Phylogenetic analysis of the 16S rRNA gene revealed that the Tiger22513F strain exhibited close genetic similarity to the reference strain ETEC(MF919609.1),with 99.9%nucleotide similarity,and resided on the same evolutionary branch.The Tiger22513F strain contained 11 antibiotic resistance genes(tetA,sul1,sul3,cmlA,floR,blaTEM,blaSHV,blaCMY-2,qnrA,qnrS,and qnrD)along with five virulence genes(VT1,fyuA,tsh,iucD,and ST).Mouse lethality tests indicated significant pathogenicity toward mice,affecting primarily the lungs,liver,and intestines.Antibiotic susceptibility testing demonstrated that this strain exhibited resistance to various classes of beta-lactam antibiotics,as well as quinolones and aminoglycosides.This investigation successfully isolated a multi-drug resistant enterotoxigenic Escherichia coli strain with pronounced pathogenicity from the liver of a deceased tiger;thus providing valuable scientific insights for clinical diagnosis,as well as prevention and control measures,against ETEC infections in South China tigers.

This study investigated the potential pathogenicity and genetic characteristics of ST314 Salmonella Kentucky(S.Ken-tucky)isolates from a broiler slaughterhouse.Antimicrobial susceptibility testing and whole-genome sequencing(WGS)were used to determine antimicrobial resistance,virulence factors,and the presence of antimicrobial resistance genes(ARGs)and mobile genetic elements(MGEs)among the isolates.The three multidrug resistant(MDR)isolates exhibited high resistance to multiple antimicrobial agents.The F4-2S strain exhibited resistance to 14 drugs across seven categories,whereas the F4T strain showed resistance to 13 drugs in the same number of categories.In contrast,the Y23 strain was resistant to nine drugs in six categories.Notably,F4-2S dem-onstrated high homology with F4T:both possessed 13 ARGs distributed across nine categories,in addition to a wide range of virulence factors,including secretion systems and effector proteins.The presence of IncR and IncX1 plasmids significantly enhanced both the antimicrobial resistance and pathogenicity of the isolates.The genome map of Y23 revealed a chromosome alongside two plasmids.The chromosome containedonly one resistance gene but several virulence factors,including the type III secretion system(T3SS),which is crucial for bacterial invasion.The plasmid pY23-1 contained eight types of 19 ARGs.Comparative analysis indicated that pY23-1 ex-hibited high homology with pZ1323SSL0055 and pSAL-045,all of which contained multiple ARGs,thus suggesting critical roles of these genes in the evolution of bacterial resistance.In conclusion,ST314 S.Kentucky demonstrated a complex mechanism of resis-tance coupled with significant pathogenic potential.The ARGs and MGEs in the plasmid contributed to the emergence and dissemina-tion of antimicrobial resistance.The multiple virulence factors present in the chromosome may be key factors driving the increasing virulence of ST314 S.Kentucky.

BACKGROUND:There is an internal relationship between hyperhomocysteinemia and vascular calcification.However,the pathogenesis of hyperhomocysteinemia promoting vascular calcification is still unclear. OBJECTIVE:To investigate the role of bone morphogenetic protein-2 in hyperhomocysteinemia-induced vascular calcification. METHODS:Human carotid wax samples were divided into a calcified group(n=29)and a non-calcified group(n=13)according to the presence or absence of calcified plaque.Sixteen ApoE-/-mice were randomly divided into a control group and a hyperhomocysteinemia group,with 8 mice in each group.Bone morphogenetic protein-2 vector was used to transfect rat thoracic artery smooth muscle A7r5 cells,and gradient concentration of homocysteine(50,100,200,and 400 μmol/L)was utilized to treat A7r5 cells.Calcification was detected by alizarin red staining and hematoxylin-eosin staining.The interaction of bone morphogenetic protein 2 with Runt-related transcription factor 2 was detected by immunofluorescence,and the expressions of bone morphogenetic protein 2,Runt-related transcription factor 2,and α-smooth muscle actin were detected by immunohistochemistry and western blot assay. RESULTS AND CONCLUSION:(1)Human carotid artery tissue staining revealed that compared with the non-calcification group,inflammatory cells increased and calcification positive rate increased in the calcification group(P<0.05).Compared with the non-calcification group,the expressions of bone morphogenetic protein-2 and Runt-related transcription factor 2 were up-regulated,and the expression of α-smooth muscle actin was decreased in the calcification group(all P<0.05).(2)The staining of mouse arterial specimens exhibited that,the positive rate of calcified area in the hyperhomocysteinemia group was significantly higher than that in the control group(P<0.05);serum homocysteine level in the hyperhomocysteinemia group was significantly higher than that in the control group(P<0.05).Compared with the control group,the expressions of bone morphogenetic protein-2 and Runt-related transcription factor 2 were up-regulated,and the expression of α-smooth muscle actin was decreased in the hyperhomocysteinemia group(all P<0.05).(3)A7r5 cell culture analysis demonstrated that with the increase of homocysteine concentration gradient,the degree of calcification,the content of bone morphogenetic protein-2 and Runt-related transcription factor 2 protein in A7r5 cells increased(P<0.05),and the content of α-smooth muscle actin protein decreased(P<0.05).(4)The A7r5 cell culture analysis of overexpressed bone morphogenetic protein 2 showed that the calcification degree of the overexpressed bone morphogenetic protein 2 group was increased compared with the corresponding control group,the β-sodium glycerophosphate group,and the homocysteine group.RUNt-related transcription factor 2 expression up-regulated(P<0.05)and α-smooth muscle actin expression down-regulated(P<0.05).(5)The expression of bone morphogenetic protein 2 increased in A7r5 cells cultured with homocysteine in calcified medium,and the expression of Runt-related transcription factor 2 increased with the increase of bone morphogenetic protein 2 expression.(6)The results confirm that bone morphogenetic protein-2 is a key target gene in the regulation of smooth muscle cell phenotypic transformation resulting in vascular calcification by hyperhomocysteinemia.Targeted regulation of bone morphogenetic protein-2 reduces hyperhomocysteinemia-induced vascular calcification.

Objective:To assess the impact of exposure to particulate matter with aerodynamic diameter ≤2.5 μm(PM2.5)on non-accidental mortality under different apparent temperature levels and to further explore the modification effect of apparent temperature.Methods:This study used time-series design.Tianjin and Ningbo from China,Bangkok and Chiang Mai from Thailand were selected as the re-search sites,and the apparent temperature was applied as the exposure index.Through the quantitative estimation of the threshold temperature,the corresponding pollutant concentration was divided into high and low levels,and the generalized Poisson additive model was used to evaluate the association between PM2.5 exposure and non-accidental death of residents at different temperature levels.Results:The ave-rage concentrations of PM2.5 in Tianjin,Ningbo,Bangkok,and Chiang Mai during the study period were(73.6±35.6),(48.0±32.1),(33.5±28.4)and(32.6±28.6)μg/m3,respectively;the average daily non-accidental death counts were 148,57,28,and 8.The analysis of the generalized Poisson addi-tive model showed that the daily non-accidental death counts increased by 0.43％(95％CI:0.33％-0.54％)per 10 μg/m3 increase of PM2.5 in lag 0 day in Tianjin of China;0.27％(95％CI:0.08％-0.46％)per 10 μg/m3 increase of PM2.5 in lag 2 days in Ningbo of China.The effect was magnified in high temperature levels in Tianjin and in low temperatures in Ningbo and Bangkok.The mortality effect of PM2 5 in various temperature levels stayed still in co-pollutant regression models.Conclusion:Exposure to fine particulate matter had an adverse effect on non-accidental mortality,which reminded us to give further attention to the pollution control.The findings also indicated that apparent temperature might modify mortality effects of PM2 .5 and the modification effect varied in different regions.Protective policies due to regional differences should be made and more scientific and social attention on mutual effect of air pollution and climate change needs to be appealed.

Human brain banks use a standardized protocol to collect,process and store post-mortem human brains and related tissues,along with relevant clinical information,and to provide the tissue samples and data as a resource to foster neuroscience research according to a standardized operating protocols(SOP).Human brain bank serves as the foundation for neuroscience research and the diagnosis of neurological disorders,highlighting the crucial rule of ensuring the consistency of standardized quality for brain tissue samples.The first version of SOP in 2017 was published by the China Human Brain Bank Consortium.As members increases from different regions in China,a revised SOP was drafted by experts from the China Human Brain Bank Consortium to meet the growing demands for neuroscience research.The revised SOP places a strong emphasis on ethical standards,incorporates neuropathological evaluation of brain regions,and provides clarity on spinal cord sampling and pathological assessment.Notable enhancements in this updated version of the SOP include reinforced ethical guidelines,inclusion of matching controls in recruitment,and expansion of brain regions to be sampled for neuropathological evaluation.

Objective:Exploring the dilemmas faced by adolescents with type 1 diabetes mellitus in self-management during the transition to adult healthcare, to inform healthcare professionals in the delivery of transitional care interventions.Methods:Using descriptive qualitative research methods, in-depth interviews were conducted from August to December 2023 to adolescents with type 1 diabetes mellitus (selected by objective sampling) who met the inclusion and exclusion criteria in the Department of Endocrinology of the First Affiliated Hospital of Guangzhou University of Traditional Chinese Medicine and the Shenzhen Children′s Hospital, and the data were analysed inductively using directed content analysis.Results:A total of 12 adolescents with type 1 diabetes mellitus were included for interview, 6 males and 6 females, aged 12-18 years. The self-management dilemmas for adolescents with type 1 diabetes in the transition to adult healthcare can be summarised into 4 themes and 10 sub-themes: disease management dilemmas (weak awareness of disease management, insufficient disease-related knowledge and competence, low adherence to disease management, and restriction of daily activities), role adaptation difficulties (lack of perceived transition to the healthcare role, difficulty in transitioning to the family role, and maladaptation to the social role), negative emotions Inadequate social support system (lack of school support, limited accessibility of social organisations, insufficient socio-economic support).Conclusions:Adolescents with type 1 diabetes mellitus face multiple dilemmas in disease self-management during the transition to adult healthcare, and healthcare professionals should pay attention to transition self-management education, improve patients′ awareness of transition self-management and their ability to participate in it, formulate a transition preparation plan, build an emotional support network, and improve the social security system, so as to help juvenile patients with type 1 diabetes master the method of self-management and make a successful transition to adulthood.

Objective To investigate the incidence rate,clinical characteristics,and prognosis of neonatal stroke in Shenzhen,China.Methods Led by Shenzhen Children's Hospital,the Shenzhen Neonatal Data Collaboration Network organized 21 institutions to collect 36 cases of neonatal stroke from January 2020 to December 2022.The incidence,clinical characteristics,treatment,and prognosis of neonatal stroke in Shenzhen were analyzed.Results The incidence rate of neonatal stroke in 21 hospitals from 2020 to 2022 was 1/15 137,1/6 060,and 1/7 704,respectively.Ischemic stroke accounted for 75％(27/36);boys accounted for 64％(23/36).Among the 36 neonates,31(86％)had disease onset within 3 days after birth,and 19(53％)had convulsion as the initial presentation.Cerebral MRI showed that 22 neonates(61％)had left cerebral infarction and 13(36％)had basal ganglia infarction.Magnetic resonance angiography was performed for 12 neonates,among whom 9(75％)had involvement of the middle cerebral artery.Electroencephalography was performed for 29 neonates,with sharp waves in 21 neonates(72％)and seizures in 10 neonates(34％).Symptomatic/supportive treatment varied across different hospitals.Neonatal Behavioral Neurological Assessment was performed for 12 neonates(33％,12/36),with a mean score of(32±4)points.The prognosis of 27 neonates was followed up to around 12 months of age,with 44％(12/27)of the neonates having a good prognosis.Conclusions Ischemic stroke is the main type of neonatal stroke,often with convulsions as the initial presentation,involvement of the middle cerebral artery,sharp waves on electroencephalography,and a relatively low neurodevelopment score.Symptomatic/supportive treatment is the main treatment method,and some neonates tend to have a poor prognosis.