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.

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.

OBJECTIVE: To investigate the potential mechanism by which electroacupuncture (EA) induces macrophage polarization to promote muscle satellite cell proliferation and differentiation, accelerating the repair of acute skeletal muscle injury. METHODS: Forty-two SPF-grade SD rats were randomly divided into three groups: a blank group (n=6), a model group (n=18), and an EA group (n=18). The model and EA groups established acute blunt contusion model of the right gastrocnemius muscle using a self-made striking device. From day 1 after modeling, rats in the EA group received EA at "Chengshan" (BL57) and "Yanglingquan" (GB34) on the right side, using disperse-dense wave with a frequency of 2 Hz/100 Hz and a current of approximately 2 mA. The EA treatment was administered once daily for 30 minutes for 3, 7, or 14 days based on the designated sampling time points. Gait analysis was performed using the Cat Walk XT^TM system. Hematoxylin-eosin (HE) staining was used to observe the morphological changes in the gastrocnemius muscle. Masson staining was applied to evaluate collagen fiber content. Immunofluorescence was used to detect the expression of proliferating cell nuclear antigen (PCNA) in muscle satellite cells. Immunohistochemistry was used to assess the expression levels of CD68 and CD206, markers of macrophages. Serum levels of pro-inflammatory cytokines (TNF-α, IL-1β) and anti-inflammatory cytokines (IL-10, IL-13) were detected using ELISA. RESULTS: Compared with the blank group, the model group showed a significant reduction in average movement speed on days 3 and 7 after modeling (P<0.05), and a decrease in the right hind limb stride length on day 3 (P<0.05). Compared with the model group, the EA group showed increased average movement speed and right hind limb stride length on day 7 (P<0.05). In the blank group, the gastrocnemius muscle on the right side showed uniform and consistent inter-fiber spacing, with neatly and regularly arranged muscle cells. In contrast, the model group exhibited enlarged inter-fiber spacing, edema, and significant infiltration of red blood cells and inflammatory cells, with progressively increasing fibrosis over time. By day 14 after modeling, the EA group showed a return to baseline levels of inflammatory cell infiltration, and the degree of fibrosis was significantly lower than that observed in the model group. Compared with the blank group, the ratio of collagen fibers in the gastrocnemius muscle of the model group increased significantly on days 3, 7, and 14 after modeling (P<0.05). Compared with the model group, the EA group exhibited a lower collagen fiber ratio on days 3, 7, and 14 (P<0.05). Compared with the blank group, PCNA positive expression in the gastrocnemius muscle of the model group was significantly increased on days 3, 7, and 14 after modeling (P<0.05). Compared with the model group, the EA group exhibited significantly higher PCNA positive expression on days 3 and 7 (P<0.05). Compared with the blank group, the model group showed a significant increase in CD68-positive macrophage expression in the gastrocnemius muscle on day 3 after modeling (P<0.05), while CD206-positive macrophage expression increased on days 3, 7, and 14 (P<0.05). Compared with the model group, CD68 expression was significantly lower in the EA group on day 3 (P<0.05), whereas CD206 expression was significantly higher on days 3 and 7 (P<0.05), peaking on day 7 with CD206 expression. Compared with the blank group, serum TNF-α levels were significantly elevated in the model group on days 3 and 7 after modeling (P<0.05), while serum IL-1β levels were increased on days 3, 7, and 14 (P<0.05). Serum IL-10 and IL-13 levels were significantly higher on day 7 after modeling (P<0.05). Compared with the model group, the EA group exhibited lower serum TNF-α level on day 3 (P<0.05) and reduced serum IL-1β levels on days 3 and 7 (P<0.05), while serum IL-10 and IL-13 levels were significantly increased on day 7 (P<0.05). CONCLUSION EA could promote the repair of acute blunt contusion-induced gastrocnemius muscle injury by regulating the proliferation and differentiation of muscle satellite cells. This process is closely related to macrophage polarization.
Animals ; Electroacupuncture ; Rats, Sprague-Dawley ; Rats ; Macrophages/immunology* ; Muscle, Skeletal/immunology* ; Male ; Humans ; Female ; Tumor Necrosis Factor-alpha/immunology* ; Cell Proliferation

BACKGROUND: Telesurgery has the potential to overcome spatial limitations for surgeons, which depends on surgical robot and the quality of network communication. However, the influence of network latency and bandwidth on telesurgery is not well understood. METHODS: A telesurgery system capable of dynamically adjusting image compression ratios in response to bandwidth changes was established between Beijing and Sanya (Hainan province), covering a distance of 3000 km. In total, 108 animal operations, including 12 surgical procedures, were performed. Total latency ranging from 170 ms to 320 ms and bandwidth from 15-20 Mbps to less than 1 Mbps were explored using designed surgical tasks and hemostasis models for renal vein and internal iliac artery rupture bleeding. Network latency, jitter, frame loss, and bit rate code were systemically measured during these operations. National Aeronautics and Space Administration Task Load Index (NASA-TLX) and a self-designed scale measured the workload and subjective perception of surgeons. RESULTS: All 108 animal telesurgeries, conducted from January 2023 to June 2023, were performed effectively over a total duration of 3866 min. The operations were completed with latency up to 320 ms and bandwidths as low as 1-5 Mbps. Hemostasis for vein and artery rupture bleeding models was effectively achieved under these low bandwidth conditions. The NASA-TLX results indicated that latency significantly impacted surgical performance more than bandwidth and image clarity reductions. CONCLUSIONS This telesurgery system demonstrated safety and reliability. A total of 320 ms latency is acceptable for telesurgery operations. Reducing image clarity can effectively mitigate the potential latency increase caused by decreased bandwidth, offering a new method to reduce the impact of latency on telesurgery.
Animals ; Robotic Surgical Procedures/methods* ; Laparoscopy/methods*

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.

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.

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.

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.

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.

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.