Objective: To understand current state of physical health levels of first year students in different body mass index (BMI) categories in Ningxia universities, and to explore the correlation between BMI and physical fitness index (PFI), so as to provide a reference for enhancing physical health levels of university students. Methods: In November 2024, physical fitness test data from 16 631 first year students across four universities in Yinchuan City, Ningxia from 2019 to 2023 were collected by adopting convenience and stratified cluster random sampling methods. The PFI was calculated using the Z score of the physical fitness test results, and a nonlinear quadratic model was established via least squares regression to examine the relationship between BMI and PFI among university students. Results: The BMI for males was (21.69±3.53)kg/m 2, while for females was (20.78±2.94)kg/m 2. The composite score for males physical fitness (69.86±9.25) was lower than that for females (72.24± 8.15 ), with a statistically significant difference ( t =-17.54, P <0.01). Moreover, the failure rates of various physical fitness indicators (vital capacity, sit and reach, standing long jump, pull ups/1 minute sit ups, 1 000 m/800 m run) were higher among males than females ( χ 2=103.48, 72.45, 14.38, 5 134.85, 188.89, all P <0.01). Comparisons across BMI categories revealed that among males, the normal weight group outperformed other groups in the 50 m sprint, standing long jump, 1 000 m sprint, composite score, and PFI ( F =89.17, 113.90, 179.02, 573.35, 593.08); among female students, the normal weight group outperformed other groups in the 50 m sprint, sit and reach, 800 m run, composite score, and PFI ( F =10.67, 19.58 , 96.45, 294.05, 183.45) (all P <0.01). The relationship between BMI and PFI among first year students exhibited a parabolic change trend, students with a moderate BMI demonstrated higher PFI, and as BMI increased, PFI decreased (all P <0.01). Conclusions The physical health level of male students in Ningxia universities is lower than that of female students. There is a correlation between BMI classification and PFI. Tailored intervention measures should be implemented according to the physical characteristics of students across different genders and BMI classifications to enhance university students physical health.

Pure red cell aplasia (PRCA) is a well-recognized complication of ABO major mismatched allogeneic hematopoietic stem cell transplantation (allo-HSCT), with a reported incidence of 10%-20% (Zhidong et al., 2012; Busca et al., 2018). It is clinically characterized by anemia, reticulocytopenia, and the absence of erythroblasts in a normal-appearing bone marrow biopsy (Shahan and Hildebrandt, 2015). The mechanism for PRCA has been presumed to be persistence of recipient isoagglutinins, produced by residual host B lymphocytes or plasma cells, which can interfere with the engraftment of donor erythroid cells (Zhidong et al., 2012). Several risk factors of PRCA at presentation are known, such as presence of anti-A isoagglutinins before transplantation, reduced intensity conditioning, absence of acute graft-versus-host disease (GVHD), sibling donors, and cyclosporin A (CsA) as GVHD prophylaxis (Hirokawa et al., 2013). PRCA is not considered to be a barrier to HSCT, as some patients can recover spontaneously or benefit from various approaches including high-dose steroids, erythropoietin (EPO), plasma exchange, immunoadsorption, donor lymphocyte infusion (DLI), treatment with rituximab, bortezomib, or daratumumab, and tapering or discontinuation of immunosuppression (Hirokawa et al., 2013; Bathini et al., 2019). However, there are still some patients who fail to respond even to aggressive treatment; they become red cell transfusion-dependent and iron-overloaded, and their life quality is impaired.

OBJECTIVE： To optimize the proteolytic enzymes for enzymolysis technology of degreasing ointment from Periplaneta americana， and to improve the extraction rate and activity of anti-liver fibrosis active part from P. americana. METHODS： Using degreasing ointment of P. americana as control， ninhydrin method and folin-ciocalteu method were used to investigate the hydrolysis degree of trypsin （TR）， pepsin （PE）， alkaline protease （AL）， papain （PA） and neutral protease （NE） to the degreasing ointment. Macroporous resin isolation and purification method was used to investigate the yield of elution part from hydrolyzate， with 50％， 60％， 70％， 95％ ethanol as eluting solvents. Inhibition test in vitro of rat hepatic stellate cells HSC-T6 was performed， and anti-liver fibrosis activity of elution part from hydrolyzate was investigated. RESULTS： The hydrolysis degree of PA and NE were 14.15％ and 15.70％， showing strong enzymatic hydrolysis ability. The yield of 95％ ethanol elution part from PA， NE and AL hydrolyzate were （0.73±0.04）％，（0.65±0.01）％ and（0.64±0.05）％， improving 30.36％， 16.07％， 14.29％ compared with degreasing ointment without enzyme. Results of inhibition test in vitro showed that inhibitory rate of 50％， 60％， 70％ ethanol elution parts isolated and  purified from hydrolyzate had a low inhibition rate or a growth-promoting effect on HSC-T6 cells. Inhibition rates of 95％ ethanol elution parts to HSC-T6 cells were all more than 20％. IC50 of 95％ ethanol elution part isolated and purified from PA and NE hydrolyzate for 24-72 h were 94.5-112.3 and 117.1-120.0 μg/mL， which were lower than that （116.1-123.0 μg/mL） of degreasing ointment without enzyme. CONCLUSIONS： PA is the best hydrolyzate for enzymolysis technology of active parts against liver fibrosis in degreasing ointment from P. americana， followed by NE and AL； PE and TR， which have poor effect， are not suitable for the enzymatic hydrolysis technology.