1.Isolation and Identification of Staphylococcus xylosus in Nude Mice with Squamous Skin Scurfs
Zhihao KONG ; Xiaofeng WEI ; Lingzhi YU ; Liping FENG ; Qi ZHU ; Guojun SHI ; Chen WANG
Laboratory Animal and Comparative Medicine 2025;45(3):368-375
Objective To isolate pathogenic bacteria from the skin of a nude mouse exhibiting squamous skin scurfs, and perform bacterial identification, traceability analysis, and pathogenicity studies to provide a new approach for the diagnosis of pathogens in nude mice with squamous skin scurfs. MethodsSkin swab samples were collected from a nude mouse exhibiting squamous skin scurfs for nucleic acid testing, bacterial isolation and culture, biochemical identification, 16S rDNA gene amplification and sequencing, and whole genome sequencing to construct a phylogenetic tree. Fifteen BALB/c nude mice were randomized into a saline-treated control group, a high-concentration group treated with 1.8×10⁸ CFU/mL of the isolated bacterial suspension, and a low-concentration group treated with 1.8×10⁷ CFU/mL of the isolated bacterial suspension. Pathogenicity was assessed by animal infection experiments and observation of histopathological changes in skin tissue using HE staining. Results The nucleic acid test for Corynebacterium bovis was negative, excluding infection by this organism. The pathogen isolated on mannitol salt agar and blood agar, combined with Gram staining, suggested a Gram-positive Staphylococcus species. The isolated strain was identified by 16S rDNA sequencing and a fully automated microbial identification system as Staphylococcus xylosus. Phylogenetic tree analysis based on whole genome sequencing showed that the strain was most closely related to an isolate from leafy vegetables in South Korea (GenBank GCA_00207825.1). In the high-concentration group, squamous skin scurfs appeared on the head, neck, and back of nude mice on the 17th day post-infection, while in the low concentration group, similar symptoms appeared on the 20th day post-infection and gradually spread to other areas. The scaling symptoms were transient, lasting for 7 days in the high-concentration group and 3 days in the low-concentration group, after which the skin returned to normal. The infection rate was 33.33% in both the high- and low-concentration groups. No significant pathological changes were observed in the skin tissues of infected mice compared to the control group, indicating marked individual differences in the pathogenicity of the strain in nude mice. Conclusion A strain of Staphylococcus xylosus was isolated from the skin of a nude mouse exhibiting squamous skin scurfs. The strain is an opportunistic pathogen that causes transient squamous skin scurfs without significant histopathological changes, and there are individual differences in the sensitivity of nude mice to this strain. These findings can provide valuable data for pathogen identification in immunodeficient or gene knockout mice.
2.Isolation and Identification of Staphylococcus xylosus in Nude Mice with Squamous Skin Scurfs
Zhihao KONG ; Xiaofeng WEI ; Lingzhi YU ; Liping FENG ; Qi ZHU ; Guojun SHI ; Chen WANG
Laboratory Animal and Comparative Medicine 2025;45(3):368-375
Objective To isolate pathogenic bacteria from the skin of a nude mouse exhibiting squamous skin scurfs, and perform bacterial identification, traceability analysis, and pathogenicity studies to provide a new approach for the diagnosis of pathogens in nude mice with squamous skin scurfs. MethodsSkin swab samples were collected from a nude mouse exhibiting squamous skin scurfs for nucleic acid testing, bacterial isolation and culture, biochemical identification, 16S rDNA gene amplification and sequencing, and whole genome sequencing to construct a phylogenetic tree. Fifteen BALB/c nude mice were randomized into a saline-treated control group, a high-concentration group treated with 1.8×10⁸ CFU/mL of the isolated bacterial suspension, and a low-concentration group treated with 1.8×10⁷ CFU/mL of the isolated bacterial suspension. Pathogenicity was assessed by animal infection experiments and observation of histopathological changes in skin tissue using HE staining. Results The nucleic acid test for Corynebacterium bovis was negative, excluding infection by this organism. The pathogen isolated on mannitol salt agar and blood agar, combined with Gram staining, suggested a Gram-positive Staphylococcus species. The isolated strain was identified by 16S rDNA sequencing and a fully automated microbial identification system as Staphylococcus xylosus. Phylogenetic tree analysis based on whole genome sequencing showed that the strain was most closely related to an isolate from leafy vegetables in South Korea (GenBank GCA_00207825.1). In the high-concentration group, squamous skin scurfs appeared on the head, neck, and back of nude mice on the 17th day post-infection, while in the low concentration group, similar symptoms appeared on the 20th day post-infection and gradually spread to other areas. The scaling symptoms were transient, lasting for 7 days in the high-concentration group and 3 days in the low-concentration group, after which the skin returned to normal. The infection rate was 33.33% in both the high- and low-concentration groups. No significant pathological changes were observed in the skin tissues of infected mice compared to the control group, indicating marked individual differences in the pathogenicity of the strain in nude mice. Conclusion A strain of Staphylococcus xylosus was isolated from the skin of a nude mouse exhibiting squamous skin scurfs. The strain is an opportunistic pathogen that causes transient squamous skin scurfs without significant histopathological changes, and there are individual differences in the sensitivity of nude mice to this strain. These findings can provide valuable data for pathogen identification in immunodeficient or gene knockout mice.
3.Evaluation of molecular point-of-care testing for rapid diagnosis of influenza A virus and influenza B virus
Xiaodong SONG ; Guojun CAO ; Min ZHU ; Yu CHEN ; Kun CHEN ; Jin XIANG ; Meijuan LU
International Journal of Laboratory Medicine 2024;45(2):146-149,154
Objective To evaluate the performance of two molecular point-of-care testing(POCT)prod-ucts in the diagnosis of influenza A virus(Flu A)and influenza B virus(Flu B)of clinical samples,and pre-liminarily evaluate the clinical diagnostic value of the changes of infection-related indicators in peripheral blood.Methods A total of 491 oropharyngeal swabs from patients with influenza-like symptoms who were treated in the hospital were recruited into this study from November 1,2019 to June 30,2023.These swabs were collected using reverse transcription real-time quantitative fluorescent polymerase chain reaction(RT-qPCR),and two POCT molecular products,XpertTM Xpress Flu/RSV and EasyNAT? Flu Assay,respectively.The diagnostic performance of two POCT molecular products was analyzed using RT-qPCR reaction as a standard.According to the results of RT-qPCR method,the subjects were divided into Flu A positive group,Flu B positive group and negative group(both Flu A and Flu B were negative).The levels of indicators in pe-ripheral blood of the three groups were compared to evaluate the value of these indicators in the clinical diag-nosis of Flu A and Flu B.Results Among the 491 patient specimens,the XpertTM Xpress Flu/RSV assay showed the sensitivity for Flu A was 96.88%,and the specificity was 99.75%,and the sensitivity for Flu B was 100.00%,and the specificity was 100.00%.EasyNAT? Flu Assay assay showed the sensitivity for Flu A was 94.79%,and the specificity was 96.81%,and the sensitivity for Flu B was 100.00%,and the specificity was 100.00%.And two POCT molecular methods performed well consistency(Kappa value was 0.974).There was no significant difference in the levels of C-reactive protein and serum amyloid A among the negative group,Flu A positive group,and Flu B positive group(P>0.05).But the levels of white blood cell count in the negative group were higher than those in the Flu A positive group and Flu B positive group(P<0.01).Conclusion In this paper,two typical molecular POCT products are studied.Their sensitivity and specificity are highly consistent with the results of RT-qPCR.Molecular POCT products have the advantages of flexibil-ity and rapidity,which are of great value for the improvement of clinical diagnosis and treatment.Molecular detection combined with peripheral blood infection related indicators is helpful for the early diagnosis of influ-enza virus infectious diseases.
4.Study on the mechanism of electroacupuncture stimulation to activate the acupoint effect and promote skeletal muscle repair
Yuting HUANG ; Jun LIAO ; Tianyu RAO ; Kezhi LIU ; Jia LIN ; Yuye LIN ; Chufan ZENG ; Guojun ZHANG ; Xia ZHANG ; Xiubing TONG ; Jingyu ZHANG ; Yu KAN ; Yanping FANG ; Xianghong JING ; Xuan WANG
Journal of Beijing University of Traditional Chinese Medicine 2024;47(8):1160-1170
Objective To investigate the mechanism of inducing macrophage polarization induced by acupoint effect of electroacupuncture to promote the repair of acute skeletal muscle injury.Methods 45 SD rats were randomly divided into blank group,model group,electroacupuncture group(EA group),sodium chrominate group (DSCG group) and electroacupuncture+sodium chrominate group (hereinafter referred to as EA+DSCG group),with 9 rats in each group. The rats in the EA group and the EA+DSCG group were subjected to EA intervention at the right "Chengshan" (BL57) and "Yanglingquan"(GB34),with a frequency of 2 Hz/100 Hz. The gait changes of rats were recorded by animal gait analyzer. The morphological changes of the right gastrocnemius were observed by HE staining. The changes of mast cell aggregation and degranulation in local skin muscles of "chengshan" point were observed by toluidine blue staining. The expressions of Pax7,MyoD and skin mast cells and 5-HT in the right gastrocnemius were detected by immunofluorescence method. The positive expressions of CD68 and CD206 in right gastrocnemius macrophage was observed by immunohistochemical staining.Results Compared with blank group,the wiggle time of the right hind leg in model group and DSCG group increased,stride length decreased,HE staining showed inflammatory cell infiltration,myocyte enlargement,degeneration and necrosis. The degranulation rate of local skin mast cells in "Chengshan" (BL57) area increased,and the expressions of mast cell tryptase,5-HT,Pax7,MyoD,CD68 and CD206 increased (P<0.05). Compared with model group,the wiggle time of the right hind leg in EA group and EA+DSCG group decreased,stride length increased,HE staining showed that inflammatory cell infiltration was reduced,muscle cells were uniform in size and arranged neatly. Mast cell degranulation rate increased significantly in EA group,and the expressions of mast cell tryptase,5-HT,Pax7,MyoD and CD206 increased (P<0.05),while CD68 expression decreased (P<0.05). Compared with EA+DSCG group,the degranulation rate of mast cells and the expressions of mast cell tryptase,5-HT,Pax7,MyoD and CD206 increased (P<0.05),while CD68 expression decreased in EA group (P<0.05). Conclusion EA "Chengshan" (BL57) and "Yanglingquan" (GB34) can stimulate acupuncture points to locally induce mast cell degranulation,promote the polarization of macrophages,and then activate muscle satellite cells to play the regulatory process of repairing skeletal muscle injury.
5.Epidemiological characteristics of human respiratory syncytial virus in Hubei Province from 2016 to 2023
Qiangling YIN ; Xiao YU ; Xiang LI ; Bin FANG ; Xiaolu ZHANG ; Mingwei PENG ; Guojun YE ; Linlin LIU
Chinese Journal of Preventive Medicine 2024;58(8):1129-1134
Objective:To analyze the epidemiological characteristics of human respiratory syncytial virus (HRSV) in patients with acute respiratory infection (ARIs) in sentinel hospitals of the Hubei influenza surveillance network from 2016 to 2023.Methods:ARIs samples [including influenza-like cases (ILI) and severe acute respiratory infection (SARI)] were collected from influenza surveillance sentinel hospitals in Hubei Province from 2016 to 2023, and case information was collected. HRSV virus nucleic acid typing was performed by fluorescence quantitative PCR method, and the data were collated, plotted and analyzed.Results:From 2016 to 2023, 12 779 cases of ILI and 9 166 cases of SARI were collected. The positive rate of HRSV was the highest in<5 years of age group [15.77% (168/1 065)], among which the positive rate was the highest in 2 to 5 years of age group of ILI cases [13.60% (31/228)], and the positive rate was the highest in 0 to 2 years of age group of SARI cases [25.97% (60/231)] (all P values<0.001). The positive rate of HRSV in SARI cases was 2.31%-25.97%, higher than that in ILI cases (0-13.60%) ( P=0.016). HRSV was prevalent in autumn and winter from 2016 to 2020 and in spring in 2023. Alternating epidemics of HRSV virus type A and B in Hubei Province from 2016 to 2023 (dominant epidemics of type B in 2016 and 2020; dominant epidemics of type A in 2017-2019 and 2023). Conclusion:SARI and ILI patients under five years old are the main infection groups of HRSV. The seasonal prevalence characteristics of HRSV in Hubei Province from 2016 to 2023 shift from autumn and winter to spring.
6.Effects of agaric polysaccharides on antioxidant capacity,serum immune indexes and intestinal flora of calves
Qiru WANG ; Yu ZHANG ; Guojun JIANG ; Haiyan LIU ; Xin HE ; Xinchao SHI ; Xing-Hua ZHAO
Chinese Journal of Veterinary Science 2024;44(6):1290-1298
This experiment was conducted to investigate the effects of agaric polysaccharides on an-tioxidant capacity,immune function,and intestinal flora of calves.Twenty-four healthy Holstein calves of(30±3)days of age and with the similar body weight at(55.33±1.86)kg were selected and randomly divided into two groups:the control group(group C)and test group(group T)with 12 replicates in each group and one calves in each replicate.Group C was fed starter and milk repla-cer,and group T was fed starter and milk replacer with 10 g of agaric polysaccharides to each calve for 10 d.Serum antioxidant,immune indexes and intestinal flora were tested.The results showed as follows:compared with group C,the enzyme activities of SOD and GSH-Px in serum of calves in group T were significantly increased(P<0.05),and were increased by 29.09%and 15.35%,re-spectively;compared with group C,IgA,IL-2 and TNF-α were significantly increased in T group(P<0.05).Adding agaric polysaccharides significantly increased the relative abundance of Firmi-cutes(P<0.05)and decreased the relative abundance of Proteobacteria in feces of calf(P>0.05);the relative abundance of Lactobalillus and Faecalibacterium were increased(P<0.05);the relative abundance of Butyricoccus-pullicaecorum was increased(P<0.05).LEfSe analysis results showed that there were 11 marker species in group T,such as Firmicutes and Lactobacillus,and 9 marker species in group C,such as Proteobacteria.The results showed that agaric polysaccharides could improve the antioxidant capacity and immune function of calves,and also could improve the structure of intestinal flora.
7.Isolation and identification of feline calicivirus and preparation of its inactivated vaccine
Yanmei YANG ; Junnan KE ; Yu QI ; Honglin REN ; Guojun ZHANG ; Zengshan LIU ; Liheng ZHANG ; Zhaozhe WANG ; Xianfeng LIU
Chinese Journal of Veterinary Science 2024;44(9):1892-1897
A virus was successfully isolated from a sick cat exhibiting clinical signs such as oral mu-cosal ulceration,nasal mucosal redness,and increased nasal secretions utilizing F81 cells.Through a comprehensive analysis as such PCR amplication,sequencing,morphology,serology,and animal re-gression tests,the virus was identified as a feline calicivirus and named FCV-BJ,an inactivated vac-cine was developed from this isolated strain its safety and efficacy were assessed.The results re-vealed that the isolated FCV-BJ strain exhibited characteristic serological and morphological fea-tures consistent with caliciviruses.Furthermore,inoculation of cats with the FCV-BJ demonstrated the strain is highly virulent and the cats manifested the clinical signs of feline calicivirus infection.For the vaccination trial,domestic cats were immunized with inactivated fifth-generation virus cell culture at varying dilutions,followed by a booster immunization after 21 days.Fourteen days after the challenge with the virus,cats immunized with 107.0 TCID50/mL or higher remained largely healthy,while all cats in the control group developed clinical signs of FCV.These findings suggest that the inactivated vaccine derived from the FCV-BJ isolate exhibits strong immunogenicity and protective efficacy at a minimum immunization dose of 107.0 TCID50/mL.This strain holds promise as a candidate for vaccine production,providing a valuable reference and foundation for future re-search and development of feline calicivirus vaccines.
8.Epidemiological characteristics of human respiratory syncytial virus in Hubei Province from 2016 to 2023
Qiangling YIN ; Xiao YU ; Xiang LI ; Bin FANG ; Xiaolu ZHANG ; Mingwei PENG ; Guojun YE ; Linlin LIU
Chinese Journal of Preventive Medicine 2024;58(8):1129-1134
Objective:To analyze the epidemiological characteristics of human respiratory syncytial virus (HRSV) in patients with acute respiratory infection (ARIs) in sentinel hospitals of the Hubei influenza surveillance network from 2016 to 2023.Methods:ARIs samples [including influenza-like cases (ILI) and severe acute respiratory infection (SARI)] were collected from influenza surveillance sentinel hospitals in Hubei Province from 2016 to 2023, and case information was collected. HRSV virus nucleic acid typing was performed by fluorescence quantitative PCR method, and the data were collated, plotted and analyzed.Results:From 2016 to 2023, 12 779 cases of ILI and 9 166 cases of SARI were collected. The positive rate of HRSV was the highest in<5 years of age group [15.77% (168/1 065)], among which the positive rate was the highest in 2 to 5 years of age group of ILI cases [13.60% (31/228)], and the positive rate was the highest in 0 to 2 years of age group of SARI cases [25.97% (60/231)] (all P values<0.001). The positive rate of HRSV in SARI cases was 2.31%-25.97%, higher than that in ILI cases (0-13.60%) ( P=0.016). HRSV was prevalent in autumn and winter from 2016 to 2020 and in spring in 2023. Alternating epidemics of HRSV virus type A and B in Hubei Province from 2016 to 2023 (dominant epidemics of type B in 2016 and 2020; dominant epidemics of type A in 2017-2019 and 2023). Conclusion:SARI and ILI patients under five years old are the main infection groups of HRSV. The seasonal prevalence characteristics of HRSV in Hubei Province from 2016 to 2023 shift from autumn and winter to spring.
9.Correlation and consistency evaluation between electrochemiluminescence and direct chemiluminescence in detecting 12 tumor markers
Miao MA ; Jie LIU ; Ruimin MA ; Pingyan LI ; Jing LU ; Huiwen XU ; Danwei YU ; Guojun ZHANG
China Medical Equipment 2024;21(5):20-25
Objective:To assess the correlation and consistency of electrochemiluminescence and direct chemiluminescence in detecting 12 tumor markers.Methods:A total of 2426 serum specimens were selected from the physical examination in Beijing Tiantan Hospital,Capital Medical University from March to August 2023.These specimens included 446 cases for alpha fetoprotein(AFP),284 cases for carcinoembryonic antigen(CEA),289 cases for carbohydrate antigen 72-4(CA72-4),87 cases for carbohydrate antigen 19-9(CA19-9),205 cases for carbohydrate antigen 125(CA-125),216 cases for carbohydrate antigen 15-3(CA 15-3),292 cases for total prostate specific antigen(TPSA),292 cases for free prostate specific antigen(FPSA),84 cases for serum cytokeratin 19 fragment(Cyfra21-1),84 cases for neuron specific enolase(NSE),84 cases for squamous cell carcinoma associated antigen(SCC)and 63 cases for pro-gastrin-releasing peptide(PROGrp).The electrochemiluminescence and direct chemiluminescence methods were respectively used to detect the above 12 indexes,and then,the correlation and consistency between the two detection methods were analyzed.Results:The results of Pearson and Spearman correlation analysis showed that there were significantly positive correlations between electrochemiluminescence and direct chemiluminescence methods in detecting 12 tumor indexes(AFP,CEA,CA72-4,CA19-9,CA125,CA15-3,TPSA,FPSA,Cyfra21-1,NSE,SCC and PROGrp)(r=0.971,0.934,0.945,0.975,0.900,0.948,0.994,0.984,0.982,0.828,0.879,0.922,P<0.05),respectively.The total coincidence rates between the two methods were respectively 98.21%,98.24%,98.27%,98.85%,97.07%,99.54%,99.66%,99.32%,92.86%,92.86%,95.24%and 96.83%.There were consistencies between electrochemiluminescence and direct chemiluminescence methods for 10 indexes excepted CA15-3 and NSE that could not calculate Kappa values due to data reasons(Kappa=0.848,0.728,0.930,0.794,0.485,0.887,0.664,0.540,0.477,0.652,P<0.05),respectively.Conclusion:In the detections of electrochemiluminescence and direct chemiluminescence methods for tumor indexes,there are favorable correlations and consistencies between them in detecting AFP,CA72-4,CA19-9 and TPSA,and there are favorable correlations between them in detecting CEA,CA125,FPSA,Cyfra21-1,SCC and PROGrp but the consistencies between them are average in detecting these indexes,and there are favorable correlations between them in detecting CA15-3 and NSE.Clinical detection should pay attention to there may be differences in the results between different detection methods when the detection is conducted in reference laboratory.
10.A case of dilated cardiomyopathy caused by FHL2 gene variant and a literature review.
Chunrui YU ; Lijuan JIA ; Chanjuan HAO ; Bianjing ZUO ; Wei LI ; Fangjie WANG ; Jun GUO
Chinese Journal of Medical Genetics 2023;40(3):337-343
OBJECTIVE:
To explore the clinical phenotype and genetic features of a child with dilated cardiomyopathy (DCM).
METHODS:
Clinical data of the child who had presented at the Zhengzhou Children's Hospital on April 28, 2020 was collected. Trio-whole exome sequencing (trio-WES) was carried out for the child and her parents, and candidate variants were validated by Sanger sequencing. "FHL2" was taken as the key word to retrieve related literature from January 1, 1997 to October 31, 2021 in the PubMed database and was also searched in the ClinVar database as a supplement to analyze the correlation between genetic variants and clinical features.
RESULTS:
The patient was a 5-month-old female infant presented with left ventricular enlargement and reduced systolic function. A heterozygous missense variant c.391C>T (p.Arg131Cys) in FHL2 gene was identified through trio-WES. The same variant was not detected in either of her parents. A total of 10 patients with FHL2 gene variants have been reported in the literature, 6 of them had presented with DCM, 2 with hypertrophic cardiomyopathy (HCM), and 2 with sudden unexplained death (SUD). Phenotypic analysis revealed that patients with variants in the LIM 3 domain presented hypertrophic cardiomyopathy and those with variants of the LIM 0~2 and LIM 4 domains had mainly presented DCM. The c.391C>T (p.Arg131Cys) has been identified in a child with DCM, though it has not been validated among the patient's family members. Based on the guidelines of the American College of Medical Genetics and Genomics, the c.391C>T(p.Arg131Cys) variant was re-classified as likely pathogenic (PS2+PM2_Supporting+PP3+PP5).
CONCLUSION
The heterozygous missense variant of c.391C>T (p.Arg131Cys) in the FHL2 gene probably predisposed to the DCM in this child, which has highlighted the importance of WES in the clinical diagnosis and genetic counseling.
Female
;
Humans
;
Cardiomyopathy, Dilated/genetics*
;
Cardiomyopathy, Hypertrophic
;
Genetic Counseling
;
Genomics
;
Heterozygote
;
Muscle Proteins/genetics*
;
Transcription Factors
;
LIM-Homeodomain Proteins/genetics*

Result Analysis
Print
Save
E-mail