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 epidemiological and clinical characteristics of RSV among patients aged ≥60 years in Beijing from 2015 to 2023.Methods:Based on the respiratory pathogen surveillance system, samples of upper respiratory tract infections (URTI), non-severe community-acquired pneumonia (nsCAP) and severe community-acquired pneumonia (sCAP) among people aged ≥60 years were collected from 28 sentinel hospitals in 16 districts of Beijing from January 2015 to December 2023. Swab samples were collected from URTI within one week, and lower respiratory tract samples from nsCAP and sCAP were collected. Demographic and epidemiological data were also collected. Various respiratory pathogens including RSV were detected.Results:From January 2015 to December 2023, a total of 20 349 cases of acute respiratory infections aged ≥60 years were included, with the RSV-positive rate of 1.54% (313/20 349, 95% CI: 1.39%-1.68%). Among them, the total RSV-positive rates of older people during the pre-pandemic, pandemic, and post-pandemic periods of COVID-19 were 1.59% (207/13 006, 95% CI: 1.38%-1.81%), 0.82% (38/4 650, 95% CI: 0.56%-1.08%) and 2.53% (68/2 693, 95% CI: 1.93%-3.12%), respectively. The difference in RSV-positive rate was statistically significant ( P<0.001). Based on the sampling time of cases, the RSV epidemic season for older people in Beijing was from October to March of the following year, with a peak period in December or January of the following year. In the post COVID-19 pandemic, there were very few RSV-positive cases detected in the elderly from April to June 2023, with only one positive case detected in May and one in June. The RSV-positive rate of older people increased significantly from October to December, reaching 11.75% (51/383) in December. Among 263 RSV-positive cases in the elderly, RSV-A, RSV-B and unclassified type accounted for 43.35% (114/263), 29.28% (77/263) and 27.38% (72/263), respectively. Since 2020, there has been a subtype conversion, with RSV-B being the main focus. Among 197 elderly cases that have complete clinical data, the main symptoms were cough (86.8%, 171/197), sputum (80.2%, 158/197) and fever (73.60%, 145/197). About 24.87% (49/197) of elderly cases experienced complications. The hospitalization mortality rate was 4.57% (9/197), and the hospitalization rate was 78.68% (155/197). The ICU occupancy rate was 1.99% (36/197). The mechanical ventilation usage rate was 13.32% (33/197), and the length of hospital stay [ M ( Q1, Q3)] was 12 (9, 16) days. Conclusion:In Beijing, the RSV infection rate is relatively low during the COVID-19 pandemic, and the prevalence of COVID-19 is relatively high. In 2023, there was no out-of-season outbreak of RSV infection among the elderly. Elderly RSV infection cases have multiple complications, severe diseases, and poor prognosis.

The application of lasers in urology has expanded due to the development and application of various wavelengths of lasers and improvements in optical fiber performance. Particularly in the areas of benign prostatic hyperplasia, bladder tumors, and urinary calculus, lasers have gradually replaced traditional surgical tools to become standard surgical equipment. Upper urological tract tumors and urinary tract stenosis are two other rapidly developing applications for lasers. An overview of the state of laser application in urology, some clinical issues, and future directions are provided in this review.

BACKGROUND:Intervertebral disc degeneration is clinically considered to be the main cause of low back pain,but due to the unclear pathogenesis of intervertebral disc degeneration,there is still a lack of effective means to delay the progression of the disease.Single-cell RNA sequencing technology can amplify and sequence mRNA at the single-cell level,reveal the gene expression intensity of a single cell,discover different cell subsets in tissues according to the heterogeneity of cells,study the pathogenesis of intervertebral disc degeneration at the molecular level,and provide a new theoretical basis for its early diagnosis and treatment. OBJECTIVE:To introduce the basic principles of single-cell RNA sequencing technology and review the research progress of single-cell RNA sequencing technology in intervertebral disc degeneration in recent years. METHODS:A computer was used to search PubMed,Web of Science,CNKI and WanFang databases for the literature published from 2012 to 2022.Key words were"single-cell RNA sequencing,intervertebral disc degeneration,sequencing Technology"in Chinese and English.Duplicate,poor-quality and irrelevant articles were excluded;a total of 70 articles were eventually included. RESULTS AND CONCLUSION:(1)We identified new cell subsets such as homeostatic chondrocytes,hypertrophy chondrocyte-like nucleus pulposus cells and fibrous nucleus pulposus cells,identified the marker genes and transcription factors of these cell subsets,and described the functions,differentiation paths and cell fate of these cell subsets during the development and progression of intervertebral disc degeneration,and proposed the concept of progenitor nucleus pulposus cells.A cell subpopulation with progenitor nucleus pulposus cells properties was identified and its effectiveness in treating intervertebral disc degeneration was verified in mice.(2)Fibro chondrocyte-like annulus fibrosus cells and annulus fibrosus stem cells with both cartilage and fiber properties were identified,and a new type of composite hydrogel was prepared by combining fibrous cartilage inducers silk fibroin and hyaluronic acid in vitro.Experiments in mice demonstrated that this hydrogel could repair both annulus fibrosus tissue and cartilage matrix,and was remarkably effective in the treatment of intervertebral disc degeneration.(3)Regulatory chondrocytes were found in endplate cartilage.Two distinct fates in the progression of intervertebral disc degeneration were analyzed and the differential genes in the two fates were identified.Intercellular communication analysis indicated that regulatory chondrocytes interact with endothelial cells to promote angiogenesis.(4)Immune cells such as macrophages,T cells,myeloid progenitor cells and neutrophils were identified in the degenerated intervertebral disc tissues,demonstrating the existence of immune response during intervertebral disc degeneration.It was found that apolipoprotein induced the polarization of macrophages M1 and M2 subtypes,and this polarization process affected the activity of progenitor nucleus pulposus cells by amplifying the inflammatory response through the MIF signaling pathway.

ObjectiveTo explore the intervention effect and molecular mechanism of Dabufei decoction in Dunhuang formula combined with cisplatin on Lewis lung adenocarcinoma-bearing mice. MethodFifty C57BL/6J mice were used， with 10 randomly assigned to the blank group （without modeling）， and 40 subcutaneously inoculated with Lewis cells to establish a Lewis lung adenocarcinoma-bearing mouse model. These 40 mice were randomly divided into the following four groups （with 10 mice in each group）： Model group （equal volume of physiological saline）， cisplatin group （5 mg·kg^-1）， Dabufei decoction group （14.35 g·kg^-1·d^-1）， and Dabufei decoction combined with cisplatin group （Dabufei decoction 14.35 g·kg^-1·d^-1 + cisplatin 5 mg·kg^-1）. Each group was treated continuously for 14 days. The general condition of the mice was observed， body weight changes were recorded， and the tumor inhibition rate， spleen index， and thymus index were calculated. Peripheral blood white blood cell （WBC）， platelet （PLT）， and hemoglobin （HGB） were detected by routine blood tests. Flow cytometry was used to detect the expression of CD4⁺CD25⁺FoxP3⁺ regulatory T cells （Treg） and natural killer （NK） cells in the spleen. Western blot and real-time quantitative polymerase chain reaction （Real-time PCR） were used to determine the expression of proteins and mRNA related to the phosphatidylinositol 3-kinase （PI3K）/protein kinase B （Akt）/mammalian target of rapamycin （mTOR） signaling pathway in tumor tissues. ResultCompared with the blank group， the model group showed decreased body weight （P<0.05）， spleen index， and thymus index （P<0.05）， decreased percentage of NK cells in the spleen （P<0.05）， increased percentage of Treg cells （P<0.05）， and decreased counts of WBC， PLT， and HGB （P<0.05）. Compared with the model group， the Dabufei decoction group exhibited significant tumor growth inhibition， increased body weight， and reduced tumor weight （P<0.05）， increased percentage of NK cells （P<0.05）， decreased proportion of Treg cells （P<0.05）， and increased counts of WBC， PLT， and HGB （P<0.05）. In the cisplatin group， tumor growth was significantly inhibited， body weight significantly decreased （P<0.05）， and tumor weight significantly reduced （P<0.05）. The spleen index and thymus index decreased （P<0.05）， and the percentage of Treg cells significantly decreased （P<0.05）. The counts of WBC， PLT， and HGB significantly decreased （P<0.05）. In the Dabufei decoction combined with cisplatin group， tumor growth was significantly inhibited， and tumor weight significantly reduced （P<0.05）. The levels of phosphorylated PI3K， Akt， and mTOR proteins and mRNA in tumor tissues were significantly reduced in all medication groups （P<0.05）. Compared with the cisplatin group， the Dabufei decoction combined with cisplatin group showed significantly inhibited tumor growth， reduced tumor weight （P<0.05）， increased body weight （P<0.05）， increased spleen index and thymus index （P<0.05）， increased percentage of NK cells （P<0.05）， decreased percentage of Treg cells （P<0.05）， significantly increased counts of WBC， PLT， and HGB （P<0.05）， and reduced levels of phosphorylated PI3K， Akt， and mTOR and their mRNA （P<0.05）. ConclusionDabufei decoction combined with cisplatin has a synergistic effect with reduced toxicity， effectively regulating immune function， increasing the proportion of NK cells， reducing the proportion of Treg cells， improving bone marrow suppression， and downregulating the PI3K/Akt/mTOR signaling pathway to inhibit tumor growth in Lewis lung adenocarcinoma-bearing mice.

Objective To establish and evaluate a method for rapid and sensitive S.xylosus detection using qPCR(real-time quantitative PCR).Methods A gehM gene fragment was selected as the target for S.xylosus.A set of specific primers was synthesized and a qPCR method was established to detect S.xylosus.A S.xylosus standard strain and other non-target strains were chosen for analysis.DNA of S.xylosus was diluted 10-fold to determine its sensitivity.Clinical samples were tested,and positive products were sequenced.The result were compared with those of bacterial culture.Results S.xylosus had a specific amplification curve,whereas other non-S.xylosus species did not,indicating that the primers were specific for S.xylosus.Sensitivity was 100 fg/μL DNA.Repeatability within and between groups was less than 3％.A total of 60 clinical samples were analyzed,of which five samples had a typical S curve.qPCR products were sequenced and BLAST searched.The similarity of the gene sequences was 99.63％,indicating that the sample was positive for the S.xylosus gehM gene with a positivity rate of 8.3％.However,the positivity rate of bacterial culture was 6.7％.The positivity rate of qPCR was slightly higher than that of the culture.Conclusions The established qPCR method is rapid with high sensitivity and specificity,and can be used to detect S.xylosus.

Objective:To examine the burden and trends of acute viral hepatitis in Guangdong Province from 1990 to 2019, and provide reference evidences for hepatitis prevention and control in the province.Methods:Data on acute viral hepatitis (hepatitis A, B, C, and E) in Guangdong from 1990 to 2019 were extracted from the Global Burden of Disease Study 2019 database. The incidence, prevalence, mortality, and disability-adjusted life years (DALY) data were analyzed by age and gender, and the estimated annual percentage change (EAPC) was calculated to describe the changing trends in disease burden.Results:From 1999 to 2019, the standardized incidence, prevalence, mortality, and DALY of acute viral hepatitis in Guangdong were higher than the national averages. In 2019, 51.43% (2 245 087/4 365 221) of acute viral hepatitis cases in Guangdong Province were mainly attributed to hepatitis B, and 77.18% (106/138) of deaths were due to acute hepatitis B. In different age groups, except for acute hepatitis B, which was more common in adults, the incidence rates of other types of viral hepatitis such as hepatitis A, B, and E showed an overall decreasing trend with age. The mortality rates of different types of acute viral hepatitis, except for the <5 age group, increased with age. The overall incidence and mortality rates of acute viral hepatitis were higher in men than in women.Conclusions:The overall burden of acute viral hepatitis in Guangdong declined in 2019, but remained higher than the national level. Further efforts are needed to strengthen hepatitis prevention and screening in different population in Guangdong Province, especially in children and the elderly.

Objective:To investigate the epidemiological and clinical characteristics of RSV among patients aged ≥60 years in Beijing from 2015 to 2023.Methods:Based on the respiratory pathogen surveillance system, samples of upper respiratory tract infections (URTI), non-severe community-acquired pneumonia (nsCAP) and severe community-acquired pneumonia (sCAP) among people aged ≥60 years were collected from 28 sentinel hospitals in 16 districts of Beijing from January 2015 to December 2023. Swab samples were collected from URTI within one week, and lower respiratory tract samples from nsCAP and sCAP were collected. Demographic and epidemiological data were also collected. Various respiratory pathogens including RSV were detected.Results:From January 2015 to December 2023, a total of 20 349 cases of acute respiratory infections aged ≥60 years were included, with the RSV-positive rate of 1.54% (313/20 349, 95% CI: 1.39%-1.68%). Among them, the total RSV-positive rates of older people during the pre-pandemic, pandemic, and post-pandemic periods of COVID-19 were 1.59% (207/13 006, 95% CI: 1.38%-1.81%), 0.82% (38/4 650, 95% CI: 0.56%-1.08%) and 2.53% (68/2 693, 95% CI: 1.93%-3.12%), respectively. The difference in RSV-positive rate was statistically significant ( P<0.001). Based on the sampling time of cases, the RSV epidemic season for older people in Beijing was from October to March of the following year, with a peak period in December or January of the following year. In the post COVID-19 pandemic, there were very few RSV-positive cases detected in the elderly from April to June 2023, with only one positive case detected in May and one in June. The RSV-positive rate of older people increased significantly from October to December, reaching 11.75% (51/383) in December. Among 263 RSV-positive cases in the elderly, RSV-A, RSV-B and unclassified type accounted for 43.35% (114/263), 29.28% (77/263) and 27.38% (72/263), respectively. Since 2020, there has been a subtype conversion, with RSV-B being the main focus. Among 197 elderly cases that have complete clinical data, the main symptoms were cough (86.8%, 171/197), sputum (80.2%, 158/197) and fever (73.60%, 145/197). About 24.87% (49/197) of elderly cases experienced complications. The hospitalization mortality rate was 4.57% (9/197), and the hospitalization rate was 78.68% (155/197). The ICU occupancy rate was 1.99% (36/197). The mechanical ventilation usage rate was 13.32% (33/197), and the length of hospital stay [ M ( Q1, Q3)] was 12 (9, 16) days. Conclusion:In Beijing, the RSV infection rate is relatively low during the COVID-19 pandemic, and the prevalence of COVID-19 is relatively high. In 2023, there was no out-of-season outbreak of RSV infection among the elderly. Elderly RSV infection cases have multiple complications, severe diseases, and poor prognosis.