ObjectiveTo establish and characterize an inducible， CD4+ T cell-specific ablation mouse model （CD4-iDTR） using the Cre-loxP and diphtheria toxin receptor （DTR） systems， and to evaluate its depletion efficacy and specificity. MethodsCD4-iDTR mice were generated through cross-breeding， with genotypes confirmed via PCR-based screening. Mice were categorized into an untreated （control） group and a diphtheria toxin （DT） induction group. Flow cytometry was employed to compare the baseline distribution of CD4⁺ T cells between untreated CD4-iDTR and wild-type C57BL/6 mice.In the DT group， CD4⁺ T cell ablation was induced by subcutaneous DT administration. The depletion efficiency in skin tissues and skin-draining lymph nodes （sdLNs） was quantified at 24 h and 1 week post-injection. Furthermore， the proportions of neutrophils， macrophages， dendritic cells， and other CD11b⁺ immune cell subsets in the skin were monitored to assess the model specificity. ResultsGenomic profiling confirmed the successful generation of the CD4-iDTR line. Under steady-state conditions， no significant differences were observed in the frequency or absolute number of CD4⁺ T cells in the skin and sdLNs between CD4-iDTR and C57BL/6 mice （P>0.05）. Following DT induction， the CD4⁺ T cell population in the skin exhibited decline within 24 h and 1 week （P<0.05）， whereas the CD4⁺ T cell counts in sdLNs remained stable. The percentages of cutaneous neutrophils， macrophages， and other CD11b⁺ myeloid populations were not significantly altered following DT treatment （P>0.05）. ConclusionThe CD4-iDTR mouse model is successfully established and bred， achieving efficient， specific， and inducible ablation of cutaneous CD4⁺ T cells without significant interference with the skin immune microenvironment. This model serves as an ideal experimental tool for investigating skin-specific immunological mechanisms.

Objective:To analyze the epidemiological characteristics and delay in detection of reported brucellosis cases in Nangang District of Harbin City, Heilongjiang Province, in order to provide a basis for improving targeted measures for brucellosis prevention and control.Methods:Data on brucellosis reported in Nangang District of Harbin City between 2018 and 2022 were obtained from the China Disease Prevention and Control Information System. A descriptive analysis was conducted to outline the epidemiological status, epidemiological features, and sources of cases. Seasonal patterns of brucellosis were assessed using the concentration degree and seasonal index methods. Joinpoint regression model was used to analyze the trend of delay in detection.Results:From 2018 to 2022, a total of 4 428 cases of brucellosis were reported in Nangang District, with 1 183 cases (26.72%) reported in 2018 and 528 cases (11.92%) reported in 2022. The gender ratio of the cases was 2.80 ∶ 1.00 (3 264 ∶ 1 164). Most cases occurred in individuals aged 30 to 59 years (73.19%, 3 241/4 428). Occupationally, farmers comprised the majority of cases (88.73%, 3 929/4 428), followed by homemakers/unemployed individuals (3.73%, 165/4 428), and students (2.03%, 90/4 428). Regarding case origin, 31.48% (1 394/4 428) were from Harbin City, while 64.97% (2 877/4 428) originated from other cities within Heilongjiang Province, predominantly from Suihua City (38.89%, 1 722/4 428). Additionally, 157 cases (3.55%, 157/4 428) were reported from outside Heilongjiang Province, all of which were from Inner Mongolia Autonomous Region and Jilin Province. Brucellosis incidence showed weak seasonality ( M = 0.230), with the epidemic period spanning from March to August. During this period, seasonal indices C exceeded 100%, peaking in July (168.02%). From 2018 to 2022, the average annual delay rate in case detection was 20.14% (892/4 428). The delayed detection rates of brucellosis cases in each year were 30.68% (363/1 183), 17.86% (200/1 120), 17.23% (117/679), 12.75% (117/918), and 17.99% (95/528), respectively (average annual percentage change = - 17.52%, P = 0.090). Conclusions:Brucellosis in Nangang District of Harbin Citydemonstrates weak seasonality, with peak incidence occurring from March to August. Detection delays remain a concern, highlighting the need for sustained surveillance and the implementation of integrated, multi-sectoral prevention and control measures.

Objective:To analyze the epidemiological characteristics and delay in detection of reported brucellosis cases in Nangang District of Harbin City, Heilongjiang Province, in order to provide a basis for improving targeted measures for brucellosis prevention and control.Methods:Data on brucellosis reported in Nangang District of Harbin City between 2018 and 2022 were obtained from the China Disease Prevention and Control Information System. A descriptive analysis was conducted to outline the epidemiological status, epidemiological features, and sources of cases. Seasonal patterns of brucellosis were assessed using the concentration degree and seasonal index methods. Joinpoint regression model was used to analyze the trend of delay in detection.Results:From 2018 to 2022, a total of 4 428 cases of brucellosis were reported in Nangang District, with 1 183 cases (26.72%) reported in 2018 and 528 cases (11.92%) reported in 2022. The gender ratio of the cases was 2.80 ∶ 1.00 (3 264 ∶ 1 164). Most cases occurred in individuals aged 30 to 59 years (73.19%, 3 241/4 428). Occupationally, farmers comprised the majority of cases (88.73%, 3 929/4 428), followed by homemakers/unemployed individuals (3.73%, 165/4 428), and students (2.03%, 90/4 428). Regarding case origin, 31.48% (1 394/4 428) were from Harbin City, while 64.97% (2 877/4 428) originated from other cities within Heilongjiang Province, predominantly from Suihua City (38.89%, 1 722/4 428). Additionally, 157 cases (3.55%, 157/4 428) were reported from outside Heilongjiang Province, all of which were from Inner Mongolia Autonomous Region and Jilin Province. Brucellosis incidence showed weak seasonality ( M = 0.230), with the epidemic period spanning from March to August. During this period, seasonal indices C exceeded 100%, peaking in July (168.02%). From 2018 to 2022, the average annual delay rate in case detection was 20.14% (892/4 428). The delayed detection rates of brucellosis cases in each year were 30.68% (363/1 183), 17.86% (200/1 120), 17.23% (117/679), 12.75% (117/918), and 17.99% (95/528), respectively (average annual percentage change = - 17.52%, P = 0.090). Conclusions:Brucellosis in Nangang District of Harbin Citydemonstrates weak seasonality, with peak incidence occurring from March to August. Detection delays remain a concern, highlighting the need for sustained surveillance and the implementation of integrated, multi-sectoral prevention and control measures.

Acute pancreatitis-associated ascites fluid (PAAF) is a common complication in patients with acute pancreatitis (AP) and is closely associated with the severity of AP, the development of local and systemic complications, and prognosis. PAAF may originate from the leakage of abdominal blood vessels, lymphatic vessels, and pancreatic duct. Recent studies have found that early removal of PAAF by abdominal paracentesis drainage can help to reduce systemic inflammation and alleviate pancreatitis-associated organ injury, thereby improving the conditions of patients with severe AP and reducing mortality. However, it is still not completely clear how PAAF aggravates systemic inflammatory response, participates in pancreatic injury and damage of distal organs, and leads to the aggravation of disease conditions in patients with AP. Therefore, this article gives an overview of PAAF and summarizes related studies in recent years, so as to provide directions for exploring the pathophysiological process and treatment of AP.

OBJECTIVE： To establish a method for simultaneous determination of 10 isoflavones in Belamcanda chinensis， and to evaluate the differences of active ingredient content of B. chinensis from different areas. METHODS： UPLC method was adopted. The determination was performed on Waters ACQUITY UPLC BEH C18 column with mobile phase consisted of 0.5 ％ methyl-β-cyclodextrin and 0.1％ phosphate as water phase， acetonitrile as organic phase （gradient elution） at the flow rate of 0.2 mL/min. The column temperature was set at 35 ℃， and the detection wavelength was set at 265 nm. The sample size was 2 μL， and analysis time was 20 min. The contents of 10 isoflavones in 26 samples from 8 provinces， including tectoridin， iristectorin A， iristectorin B， iridin， tectorigenin， iristectorigenin B， iristectorigenin A， irigenin， irisflorentin， dichotomitin， were determined. RESULTS： The linear ranges of tectoridin， iristectorin A， iristectorin B， iridin， tectorigenin， iristectorigenin B， iristectorigenin A， irigenin， irisflorentin， dichotomitin were 8.569 5-342.78， 0.643-25.72， 1.119 8-44.79， 2.187 8-87.51， 0.770 3-30.81， 0.421 3- 16.85， 0.288 5-11.54， 1.795 3-71.81， 0.560 8-22.43， 0.086-3.44 μg/mL（all r≥0.999 6）. The limits of quantitation were 0.015， 0.102， 0.096， 0.013， 0.036， 0.088， 0.102， 0.019， 0.067， 0.092 μg/mL. RSDs of precision， stability（24 h）and reproducibility tests were lower than 2.00％ （n＝6）. The recoveries ranged 95.30％-103.30％ （all RSD≤2.33％， n＝6）. Among 26 samples of B. chinensis， the content of tectoridin was the highest （3.66％-57.79％）， and the content of dichotomitin was the lowest （0.09％- 0.59％）， the contents of irisflorentin were 0.29-2.80 mg/g. The contents of isoflavones in B. chinensis from different areas were different greatly.  CONCLUSIONS： The established method is sensitive， with short analysis time and good repeatability， and can be used to determine the content of 10 isoflavones and evaluate the content difference of each component.