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 In this study,inbred BALB/c mice infected with the pneumonia virus of mice(PVM)were used to establish an animal model of viral pneumonia,and the changes in the pro-inflammatory alarmin molecule,high mobility group box 1 protein(HMGB1),during PVM infection were observed,as well as the in vivo intervention effects of the HMGB1 inhibitor,glycyrrhizic acid(GA),on PVM-induced lung injury.Methods Three-week-old female BALB/c mice were randomly divided into three groups,each consisting of 6 mice.One group,uninfected by PVM,served as the control group(Control).The other two groups were inoculated intranasally with PVM at a dose of 1×104 50％tissue culture infective dose(TCID50)/25 μL,and subsequently treated with GA saline solution(GA group)or plain saline solution(normal saline,NS group)via gavage for 15 consecutive days.During this period,changes in body weight and appearance were monitored in each group.At the end of the experiment,lung tissue samples were collected from all groups.The distribution of PVM and HMGB1 proteins in the lung tissues was analyzed using hematoxylin-eosin staining and immunohistochemistry.The expression levels of HMGB1 and its Toll-like receptor 4(TLR-4),advanced glycosylation end-product-specific receptor(AGER),and inflammatory cytokines such as interleukin(IL)-1β,IL-2,and tumor necrosis factor-α(TNF-α)in lung tissues of mice were measured using real time fluorescence quantitative PCR.Results Compared with the Control group,the NS group showed a significant weight loss after 6 days(P＜0.05).Histopathological tests revealed pronounced inflammatory lesions in their lungs.Immunohistochemistry results showed that HMGB1 was released from the nucleus to the cytoplasm,and real time fluorescence quantitative PCR results indicated that the expression levels of HMGB1,IL-1β,and IL-2 were significantly upregulated(P＜0.05).In the GA group,there was no significant change in the clinical symptoms or body weight.However,compared with the NS group,the pathological damages of lung tissues in the GA group were significantly reduced,and the expression levels of HMGB1,IL-1 β,IL-2,and interferon-γ(IFN-γ)in lung tissues were also significantly decreased(P＜0.05),although the expression level of AGER was significantly increased(P＜0.05).Conclusion PVM infection can cause significant inflammatory pathological lung damages in mice,and GA can effectively alleviate the damages.Its therapeutic effect may be related to the activation of HMGB1 signaling pathway.

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 investigate the clinical features and therapeutic efficacy of patients with hereditary leiomyomatosis and renal cell carcinoma(RCC) syndrome-associated RCC (HLRCC-RCC) in China.Methods:The clinical data of 119 HLRCC-RCC patients with fumarate hydratase (FH) germline mutation confirmed by genetic diagnosis from 15 medical centers nationwide from January 2008 to December 2021 were retrospectively analyzed. Among them, 73 were male and 46 were female. The median age was 38(13, 74) years. The median tumor diameter was 6.5 (1.0, 20.5) cm. There were 38 cases (31.9%) in stage Ⅰ-Ⅱand 81 cases (68.1%) in stage Ⅲ-Ⅳ. In this group, only 11 of 119 HLRCC-RCC patients presented with skin smooth muscle tumors, and 44 of 46 female HLRCC-RCC patients had a history of uterine fibroids. The pathological characteristics, treatment methods, prognosis and survival of the patients were summarized.Results:A total of 86 patients underwent surgical treatment, including 70 cases of radical nephrectomy, 5 cases of partial nephrectomy, and 11 cases of reductive nephrectomy. The other 33 patients with newly diagnosed metastasis underwent renal puncture biopsy. The results of genetic testing showed that 94 patients had FH gene point mutation, 18 had FH gene insertion/deletion mutation, 4 had FH gene splicing mutation, 2 had FH gene large fragment deletion and 1 had FH gene copy number mutation. Immunohistochemical staining showed strong 2-succinocysteine (2-SC) positive and FH negative in 113 patients. A total of 102 patients received systematic treatment, including 44 newly diagnosed patients with metastasis and 58 patients with postoperative metastasis. Among them, 33 patients were treated with tyrosine kinase inhibitor (TKI) combined with immune checkpoint inhibitor (ICI), 8 patients were treated with bevacizumab combined with erlotinib, and 61 patients were treated with TKI monotherapy. Survival analysis showed that the median progression-free survival (PFS) of TKI combined with ICI was 18 (5, 38) months, and the median overall survival (OS) was not reached. The median PFS and OS were 12 (5, 14) months and 30 (10, 32) months in the bevacizumab combined with erlotinib treatment group, respectively. The median PFS and OS were 10 (3, 64) months and 44 (10, 74) months in the TKI monotherapy group, respectively. PFS ( P=0.009) and OS ( P=0.006) in TKI combined with ICI group were better than those in bevacizumab combined with erlotinib group. The median PFS ( P=0.003) and median OS ( P=0.028) in TKI combined with ICI group were better than those in TKI monotherapy group. Conclusions:HLRCC-RCC is rare but has a high degree of malignancy, poor prognosis and familial genetic characteristics. Immunohistochemical staining with strong positive 2-SC and negative FH can provide an important basis for clinical diagnosis. Genetic detection of FH gene germ line mutation can confirm the diagnosis. The preliminary study results confirmed that TKI combined with ICI had a good clinical effect, but it needs to be confirmed by the results of a large sample multi-center randomized controlled clinical study.

The rare-earth-elements-doped upconversion nanoparticles NaYF4:Yb3+,Er3+were synthesized by solvothermal method,and NaYF4:Yb3+,Er3+@SiO2 were prepared by coating SiO2 on the surface of NaYF4:Yb3+,Er3+by inverse microemulsion method in this work.Based on the fluorescence quenching principle between NaYF4∶Yb3+,Er3+@SiO2 and SQA-Fe3+,a NaYF4∶Yb3+,Er3+@SiO2-SQA-Fe3+fluorescence nanosensor was constructed for detection of trace hydrogen peroxide(H2O2).Under optimal conditions,the linear range of this method for detecting H2O2 was 1.8?84.0 μmol/L,with detection limit(3σ)of 0.47 μmol/L.The recoveries of H2O2 spiked in milk were 98.4%?99.7%.This method could be used for detection of H2O2 residue in milk samples,with advantages such as low detection limit,good stability and strong anti-interference ability.

Objective:To investigate the clinicopathological features, molecular genetic features, and differential diagnosis of intraductal carcinomas (IDC) of the salivary glands.Methods:Twenty-five cases of salivary gland IDC diagnosed at the Department of Oral Pathology, Shanghai Ninth People′s Hospital and two cases from Department of Pathology, Henan Provincial People′s Hospital, Zhengzhou, China from January 2008 to July 2023 were collected. Their clinical and pathological features were analyzed retrospectively. Fluorescence in situ hybridization and Sanger sequencing were performed. The patients were followed up and related literatures were reviewed.Results:There were 27 patients with IDC, including 15 males and 12 females, ranging in age from 20.0 to 80.0 years (mean 55.9 years). Clinically, the tumor often presented as a painless mass with a tumor diameter of 1.0-3.0 cm (mean 2.0 cm). All patients received surgical treatment. Twenty patients were followed up. One of them (1/20) died of lung cancer, while the rest survived without tumor recurrence. Histologically, IDC were classified as: intercalated (63.0%, 17/27), apocrine (25.9%, 7/27), oncocytic (7.4%, 2/27) and mixed (3.7%, 1/27) types. Intercalated tumors showed positive S-100 and negative androgen receptor (AR) immunoreactivity. Ki-67 proliferation index was low (about 1%-5%). Nine cases had the RET gene disruption, and 2 cases showed the BRAF V600E mutation. Apocrine tumors showed strong AR immunoreactivity but no S-100 immunoreactivity. Ki-67 proliferation index was high (about 10%-60%), and the RET gene rupture was detected in 1 case. Oncocytic tumors were similar to that of intercalated type in 2 cases, and RET gene disruption was detected in the both cases. Mixed tumors showed histologic features of oncocytic and apocrine patterns and harbored the RET gene disruption.Conclusions:IDC is a rare low-grade malignant tumor of the salivary gland and easily confused with other salivary gland tumors with similar morphology. Molecular testing is helpful for its differential diagnosis.

Ulcerative colitis(UC) is a recurrent, intractable inflammatory bowel disease. Coptidis Rhizoma and Bovis Calculus, serving as heat-clearing and toxin-removing drugs, have long been used in the treatment of UC. Berberine(BBR) and ursodeoxycholic acid(UDCA), the main active components of Coptidis Rhizoma and Bovis Calculus, respectively, were employed to obtain UDCA-BBR supramolecular nanoparticles by stimulated co-decocting process for enhancing the therapeutic effect on UC. As revealed by the characterization of supramolecular nanoparticles by field emission scanning electron microscopy(FE-SEM) and dynamic light scattering(DLS), the supramolecular nanoparticles were tetrahedral nanoparticles with an average particle size of 180 nm. The molecular structure was described by ultraviolet spectroscopy, fluorescence spectroscopy, infrared spectroscopy, high-resolution mass spectrometry, and hydrogen-nuclear magnetic resonance(H-NMR) spectroscopy. The results showed that the formation of the supramolecular nano-particle was attributed to the mutual electrostatic attraction and hydrophobic interaction between BBR and UDCA. Additionally, supramolecular nanoparticles were also characterized by sustained release and pH sensitivity. The acute UC model was induced by dextran sulfate sodium(DSS) in mice. It was found that supramolecular nanoparticles could effectively improve body mass reduction and colon shortening in mice with UC(P<0.001) and decrease disease activity index(DAI)(P<0.01). There were statistically significant differences between the supramolecular nanoparticles group and the mechanical mixture group(P<0.001, P<0.05). Enzyme-linked immunosorbent assay(ELISA) was used to detect the serum levels of tumor necrosis factor-α(TNF-α) and interleukin-6(IL-6), and the results showed that supramolecular nanoparticles could reduce serum TNF-α and IL-6 levels(P<0.001) and exhibited an obvious difference with the mechanical mixture group(P<0.01, P<0.05). Flow cytometry indicated that supramolecular nanoparticles could reduce the recruitment of neutrophils in the lamina propria of the colon(P<0.05), which was significantly different from the mechanical mixture group(P<0.05). These findings suggested that as compared with the mechanical mixture, the supramolecular nanoparticles could effectively improve the symptoms of acute UC in mice. The study provides a new research idea for the poor absorption of small molecules and the unsatisfactory therapeutic effect of traditional Chinese medicine and lays a foundation for the research on the nano-drug delivery system of traditional Chinese medicine.
Animals ; Mice ; Colitis, Ulcerative/drug therapy* ; Ursodeoxycholic Acid/adverse effects* ; Berberine/pharmacology* ; Interleukin-6 ; Tumor Necrosis Factor-alpha/pharmacology* ; Drugs, Chinese Herbal/pharmacology* ; Colon ; Nanoparticles ; Dextran Sulfate/adverse effects* ; Disease Models, Animal ; Colitis/chemically induced*

With the advent of artificial intelligence (AI), machines are increasingly being used to complete complicated tasks, yielding remarkable results. Machine learning (ML) is the most relevant subset of AI in medicine, which will soon become an integral part of our everyday practice. Therefore, physicians should acquaint themselves with ML and AI, and their role as an enabler rather than a competitor. Herein, we introduce basic concepts and terms used in AI and ML, and aim to demystify commonly used AI/ML algorithms such as learning methods including neural networks/deep learning, decision tree and application domain in computer vision and natural language processing through specific examples. We discuss how machines are already being used to augment the physician's decision-making process, and postulate the potential impact of ML on medical practice and medical research based on its current capabilities and known limitations. Moreover, we discuss the feasibility of full machine autonomy in medicine.
Humans ; Artificial Intelligence ; Machine Learning ; Algorithms ; Neural Networks, Computer ; Medicine

Objective: To explore the clinical characteristics of various types of infected pancreatic necrosis(IPN) and the prognosis of different treatment methods in the imaging classification of IPN proposed. Methods: The clinical data of 126 patients with IPN admitted to the Department of Pancreatic and Biliary Surgery, the First Affiliated Hospital of Harbin Medical University from December 2018 to December 2021 were analyzed retrospectively. There were 70 males(55.6%) and 56 females(44.4%), with age(M(IQR)) of 44(17)years (range: 12 to 87 years). There were 67 cases(53.2%) of severe acute pancreatitis and 59 cases (46.8%) of moderately severe acute pancreatitis. All cases were based on the diagnostic criteria of IPN. All cases were divided into Type Ⅰ(central IPN)(n=21), Type Ⅱ(peripheral IPN)(n=23), Type Ⅲ(mixed IPN)(n=74) and Type Ⅳ(isolated IPN)(n=8) according to the different sites of infection and necrosis on CT.According to different treatment strategies,they were divided into Step-up group(n=109) and Step-jump group(n=17). The clinical indicators and prognosis of each group were observed and analyzed by ANOVA,t-test,χ² test or Fisher exact test,respectively. Results: There was no significant difference in mortality, complication rate and complication grade in each type of IPN(all P>0.05). Compared with other types of patients, the length of stay (69(40)days vs. 19(19)days) and hospitalization expenses(323 000(419 000)yuan vs. 60 000(78 000)yuan) were significantly increased in Type Ⅳ IPN(Z=-4.041, -3.972; both P<0.01). The incidence of postoperative residual infection of Type Ⅳ IPN was significantly higher than that of other types (χ²=16.350,P<0.01). There was no significant difference in the mortality of patients with different types of IPN between different treatment groups. The length of stay and hospitalization expenses of patients in the Step-up group were significantly less than those in the Step-jump group(19(20)days vs. 33(35)days, Z=-2.052, P=0.040;59 000(80 000)yuan vs. 122 000(109 000)yuan,Z=-2.317,P=0.020). Among the patients in Type Ⅳ IPN, the hospitalization expenses of Step-up group was significantly higher than that of Step-jump group(330 000(578 000)yuan vs. 141 000 yuan,Z=-2.000,P=0.046). The incidence of postoperative residual infection of Step-up group(17.4%(19/109)) was significantly lower than that of Step-jump group(10/17)(χ²=11.980, P=0.001). Conclusions: Type Ⅳ IPN is more serious than the other three types. It causes longer length of stay and more hospitalization expenses. The step-up approach is safe and effective in the treatment of IPN. However, for infected lesions which are deep in place,difficult to reach by conventional drainage methods, or mainly exhibit "dry necrosis", choosing the step-jump approach is a more positive choice.
Male ; Female ; Humans ; Retrospective Studies ; Pancreatitis, Acute Necrotizing/complications* ; Acute Disease ; Intraabdominal Infections/complications* ; Necrosis/complications* ; Treatment Outcome