Objective To investigate the effect of postoperative reduction quality in femoral neck fracture internal fixation on mechanical properties of the femoral head from the perspective of trabecular bone biomechanics.Methods From patients who underwent hip replacement surgery for femoral neck fractures,a total of 26 femoral head slice specimens were obtained.The central axis of the primary compressive trabeculae was defined as the 0° group,with the intersection point of the primary compressive trabeculae and the femoral calcar serving as the center.By rotating the specimens to simulate different reduction angles,the cut femoral head slice specimens were randomly divided into five groups:-10°,-5°,0°,5°,and 10°,representing femoral heads with varying reduction qualities.The specimens were subjected to single compression load tests and fatigue load tests.The load was set from 70 N to 1 400 N,at a frequency of 1 Hz,with 10 000 cycles.Axial stiffness,displacement,and the number of collapse cycles were measured,to compare the biomechanical properties of femoral head specimens under different reduction qualities.Results There were differences in the axial stiffness,displacement,and number of collapse cycles among the femoral head specimens in different groups.Under 800 N load,the axial stiffness of 0° group was significantly greater than that of±10° groups(P＜0.05).The axial stiffness of 0° group was also greater than that of the±5° groups,but the differences were not statistically significant(P＞0.05).The axial stiffness of±5° groups was greater than that of±10° groups(P＜0.05).0° group had a lower displacement than±5° groups and±10° groups.However,the differences in displacement between 0° group and±5° groups were not statistically significant(P＞0.05),while the differences between the 0° group and±10° groups were statistically significant(P＜0.05).The differences in displacement between±5° groups and±10° groups were also statistically significant(P＜0.05).0° group had a significantly higher number of collapse cycles than±10° groups(P＜0.05).The number of collapse cycles in 0° group was also higher than that in±5° groups,but the differences were not statistically significant(P＞0.05).The number of collapse cycles in±5° groups was significantly higher than that±10° groups(P＜0.05).Conclusions The quality of reduction after internal fixation of femoral neck fractures significantly affects the biomechanical properties of the femoral head.This study provides a scientific basis for optimizing treatment and postoperative management,aiming to improve clinical outcomes and patients' quality of life.

Objective To investigate the effect of postoperative reduction quality in femoral neck fracture internal fixation on mechanical properties of the femoral head from the perspective of trabecular bone biomechanics.Methods From patients who underwent hip replacement surgery for femoral neck fractures,a total of 26 femoral head slice specimens were obtained.The central axis of the primary compressive trabeculae was defined as the 0° group,with the intersection point of the primary compressive trabeculae and the femoral calcar serving as the center.By rotating the specimens to simulate different reduction angles,the cut femoral head slice specimens were randomly divided into five groups:-10°,-5°,0°,5°,and 10°,representing femoral heads with varying reduction qualities.The specimens were subjected to single compression load tests and fatigue load tests.The load was set from 70 N to 1 400 N,at a frequency of 1 Hz,with 10 000 cycles.Axial stiffness,displacement,and the number of collapse cycles were measured,to compare the biomechanical properties of femoral head specimens under different reduction qualities.Results There were differences in the axial stiffness,displacement,and number of collapse cycles among the femoral head specimens in different groups.Under 800 N load,the axial stiffness of 0° group was significantly greater than that of±10° groups(P＜0.05).The axial stiffness of 0° group was also greater than that of the±5° groups,but the differences were not statistically significant(P＞0.05).The axial stiffness of±5° groups was greater than that of±10° groups(P＜0.05).0° group had a lower displacement than±5° groups and±10° groups.However,the differences in displacement between 0° group and±5° groups were not statistically significant(P＞0.05),while the differences between the 0° group and±10° groups were statistically significant(P＜0.05).The differences in displacement between±5° groups and±10° groups were also statistically significant(P＜0.05).0° group had a significantly higher number of collapse cycles than±10° groups(P＜0.05).The number of collapse cycles in 0° group was also higher than that in±5° groups,but the differences were not statistically significant(P＞0.05).The number of collapse cycles in±5° groups was significantly higher than that±10° groups(P＜0.05).Conclusions The quality of reduction after internal fixation of femoral neck fractures significantly affects the biomechanical properties of the femoral head.This study provides a scientific basis for optimizing treatment and postoperative management,aiming to improve clinical outcomes and patients' quality of life.

Objective:To explore the optimal index of rotational displacement of femoral neck fractures by modeling the axial rotational displacement of femoral neck fractures after reduction and based on X-ray projections.Methods:Six dry human femur specimens, comprising 2 males and 4 females, were utilized in the study. Design and manufacture a proximal femur ortholateral and oblique X-ray casting jigs and mounts. The femoral neck fracture was modeled on the femoral specimen, with Pauwells 30°, 50°, and 70° models (2 each) made according to Pauwells typing. The fractures were manually repositioned with residual anterior 20°, 40° and 60° axial rotational displacements. Each fracture model was projected at different angles (pedicled 40°, pedicled 20°, vertical 0°, cephalad 20°, and cephalad 40°), and the trabecular angle and Garden's alignment index of the model were measured to observe the imaging characteristics of the fracture line on the medial oblique and lateral oblique radiographs.Results:In the presence of a 20° and 40° anterior rotational displacement following reduction of a femoral neck fracture, the trabecular angle in the rotationally displaced group was not significantly different from that of the anatomically repositioned group in various projection positions. However, when a residual rotational displacement of 60° was present, the trabeculae appeared blurred at most projection angles in the Pauwells 30° and 50° models, failing to measure trabecular angles. In the Pauwells 70° fracture model, the trabecular angle in the rotational displacement group was significantly different from that in the anatomical reduction group. In anteroposterior radiographs, when the anterior rotation displacement was 60° in the Pauwells 70° group, Garden's contralateral index showed an unsatisfactory restoration (150°, 142°), whereas all rotationally displaced models in the Pauwells 30° and Pauwells 50° groups had a Garden's contralateral index of >155°, which achieved an acceptable restoration. In lateral radiographs, all rotational displacement models with Garden's alignment index>180° failed to achieve acceptable repositioning, and the larger the Pauwells angle the greater the Garden's alignment index at the same rotational displacement. In the internal oblique position with a bias towards the foot side, the image showed partial overlap between the femoral head and the shaft, making it difficult to assess the quality of the reduction. Conversely, when projected cephalad, the femoral neck appeared longer, particularly at a projection angle of 40° cephalad, allowing for clear observation of the fracture line and the anatomy of the proximal femur. The trabeculae were not well visualized in the external oblique position.Conclusion:There are limitations in applying the trabecular angle to assess the axial rotational displacement of the femoral head after reduction of femoral neck fractures. The Pauwells 70° with residual rotational anterior displacement of 60° was the only way to detect axial rotational displacement of the femoral head on anteroposterior radiographs Garden's alignment index. For the determination of axial rotational displacement of the femoral head, the Garden's alignment index on lateral radiographs provides higher reliability.

Objective To investigate the incidence and the types of gene mutations of α-thalassemia in the child-bearing pop-ulation of Conghua District,Guangzhou.Methods Blood samples from 24 083 people of childbearing age were screened by blood cell analysis and hemoglobin electrophoresis,α-globin gene variation was detected by GAP-PCR and PCR reverse dot blot in the positive cases,and 17 common β-globin gene mutations were detected by PCR reverse Dot blot.Results A total of 2 596 cases of α-thalassemia gene abnormality were detected by gene identification,and the abnormal rate was 10.78%.A sum of 170 cases(0.71%)had a compound mutation of α-β gene.There were 2 550 cases(98.23%)of deletion and 46 cases(1.77%)of non-deletion in the mutant genes.There were 14 types of gene mutation,including 5 types of HbH disease(with--SEA/-α3.7 primarily),4 mild types(with 68.61%of--SEA/αα genotype),and 5 quiescent types(the top two genotypes were-α3.7/αα and-α4.2/αα).A total of 23 types of αβ complex gene mutation were detected,and the top six types were--SEA/βCD41-42,-α3.7/βCD41-42,--SEA/β654,--SEA/-28,-α3.7/β654 and-α3.7/βCD17,which accounted for 75.27%of all the complex types.Conclusion The gene abnormality rate of α-thalassemia in Conghua District of Guangzhou City was high.The gene mutation type and constitu-ent ratio,which have their own characteristics,is a special region of α-thalassemia.

Objective:To investigate the role of multiparameter flow cytometry (MFC) in detecting non-neoplastic abnormal phenotypes, including monoclonal gammopathy of undetermined significance (MGUS), monoclonal B-cell lymphocytosis (MBL), Fcγ receptor Ⅲb (FcγRⅢB), and CD36 deficiencies.Methods:A retrospective and observational study was conducted on a total of 24 864 patients who underwent one-step screening for leukemia/lymphoma at Hebei Yanda Ludaopei Hospital from January 3, 2020, to March 31, 2024. Clinical data and MFC results of the patients were collected. Patients were grouped by age, group of <45 years (11 495 cases), group of 45-<60 years (5 322 cases), group of ≥60 years (7 081 cases) and disease nature, benign group (8 336 cases), malignant group (15 562), and other diseases group (966 cases). The incidence of non-neoplastic abnormal phenotypes was analyzed across groups.Results:The incidence rates of MGUS, MBL, FcγRⅢB, and CD36 deficiencies were 0.072% (18/24 864), 0.511% (127/24 864), 0.221% (55/24 864), and 0.004% (1/24 864), respectively. MBL incidence was lower in the malignant group than in the benign group ( P<0.001), while MGUS incidence was higher in the malignant group than in the benign group ( P=0.034). The incidence rate of MBL among subtypes within the benign group varied significantly ( P<0.001 ), with the highest incidence in patients with pancytopenia at 2.72% (48/1 765). In the malignant group, the incidence of MBL differed significantly across various disease types ( P<0.001), among which MDS/MPN exhibited the highest incidence at 1.95% (3/154) and 1.30% (2/154). Conclusion:Utility of multiparameter flow cytometry method for one-step screening of leukemia and lymphoma shows variety in detecting non-neoplastic abnormal phenotypes, facilitating the identification of diseases.

Objective:To explore and screen the immunophenotypic characteristics of acute promyelocytic leukemia (APL) by multiparameter flow cytometry (MFC).Methods:A retrospective and descriptive study. A total of 130 acute myeloid leukemia (AML) patients who registrated in Hebei Yanda Lu Daopei Hospital were studied, among which there were 44 classical APL (cAPL), 24 microgranular variant of APL (APLv) and 62 non-APL patients (including NPM1 mut AML and AML with KMT2A rearrangement). MFC immunotyping was used to analyze and compare the median expression intensity (MEI) of side scatter (SSC), along with the ratio of the MEI on leukemic cells with those on lymphocytes (T/L MEIR), the median fluorescence intensity (MDFI) of CD34, myeloperoxidase (MPO), CD64 and CD9 on leukemic cells, as well as the ratios of these MDFIs on leukemic cells with those on lymphocytes (T/L MDFIR). Receiver operating characteristic (ROC) curve was drawn to evaluate the diagnostic efficiency of the multiparameters model for distinguishing cAPL and non-APL, APLv and non-APL. Results:The MEI and T/L MEIR of SSC in the cAPL group were higher than those in the APLv and non-APL groups ( P<0.05), and these two parameters in APLv group were higher than those in the non-APL group, respectively ( P<0.05). The MDFIs of CD34 in cAPL and APLv groups were higher than those in the non-APL group ( P<0.05), and the T/L MDFIR of CD34 was higher in APLv group than non-APL group ( P<0.05). The MDFIs of MPO and CD9, as well as the T/L MDFIRs in cAPL and APLv groups were both higher than those in the non-APL group, respectively ( P<0.05). The MDFI and T/L MDFIR of CD64 in the cAPL group were higher than those in non-APL group, respectively ( P<0.05). ROC curve results showed that the area under the curve (AUC) of MEI of SSC, the MDFI of CD64 and CD9, as well as the T/L MEIR of SSC and T/L MDFIR of CD9 were 0.932, 0.816, 0.893, 0.960 and 0.894 for diagnosing cAPL, respectively, and the AUC of these parameters were 0.725, 0.737, 0.791, 0.729 and 0.736 for diagnosis APLv, respectively ( P<0.05). Conclusion:MFC method can analyze and screen the immunophenotypic characteristics of APL for differential diagnosis of cAPL, APLv and non-APL patients.

OBJECTIVE: To clarify the preparation methods of four rat models of liver ischemia/reperfusion injury (IRI) and to determine a liver IRI animal model that is consistent with clinical conditions, has stable pathological and physiological injury, and is easy to operate. METHODS: A total of 160 male Sprague-Dawley (SD) rats were randomly divided into four groups using an interval grouping method: 70% IRI (group A), 100% IRI (group B), 70% IRI with 30% hepatectomy (group C), and 100% IRI with 30% hepatectomy (group D), with 40 rats in each group. Each model was further divided into sham operation group (S group) and ischemia groups of 30, 60, and 90 minutes, with 10 rats in each group. After surgery, the survival status and awakening time of the rats were observed, and the liver lobectomy weight, bleeding volume, and hemostasis time of groups C and D were recorded. Blood samples were collected by cardiac puncture after 6 hours of reperfusion for determination the levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP), blood urea nitrogen (BUN), serum creatinine (SCr), and γ-glutamyl transpeptidase (γ-GT) in the serum to assess liver and kidney function. Hematoxylin-eosin (HE) staining and immunohistochemical staining of macrophages were performed to analyze the liver tissue structure damage from a pathological perspective. RESULTS: Rats in group A exhibited earlier awakening and acceptable mental status, while rats in the other groups showed delayed awakening and poor mental status. The hemostasis time in group D was approximately 1 second longer than that in group C. The mortality of rats subjected to 60 minutes of 70% hepatic ischemia was 0. Compared to the sham operation group, rats in each experimental group showed significant increases in serum levels of AST, ALT, ALP, BUN, SCr, and γ-GT, indicating impaired liver and kidney function in the rat models of liver IRI. In groups A, B, and C, the 90-minute ischemia subgroup exhibited more pronounced elevation in AST, ALT, ALP, BUN, SCr, and γ-GT levels compared to the 30-minute ischemia subgroup [AST (U/L): group A, 834.94±56.73 vs. 258.74±18.33; group B, 547.63±217.40 vs. 277.67±57.92; group C, 930.38±75.48 vs. 640.51±194.20; ALT (U/L): group A, 346.78±25.47 vs. 156.58±13.25; group B, 408.40±138.25 vs. 196.80±58.60; group C, 596.41±193.32 vs. 173.76±72.43; ALP (U/L): group A, 431.21±34.30 vs. 315.95±15.64; group B, 525.88±62.13 vs. 215.63±17.31; group C, 487.53±112.37 vs. 272.46±92.33; BUN (U/L): group A, 18.35±5.63 vs. 14.32±2.30; group B, 30.21±4.55 vs. 17.41±8.14; group C, 20.50±3.64 vs. 15.93±3.22; SCr (U/L): group A, 27.47±8.91 vs. 22.37±5.66; group B, 43.60±15.57 vs. 36.80±7.95; group C, 63.81±20.24 vs. 42.47±7.03; γ-GT (U/L): group A, 15.64±3.57 vs. 6.82±1.48; group B, 9.28±1.91 vs. 5.62±1.21; group C, 10.98±3.18 vs. 5.67±1.10; all P < 0.05]. The 100% IRI 90-minute group and 100% IRI 90-minute group with 30% hepatectomy exhibited more pronounced increases in the above-mentioned indicators compared to the corresponding 70% IRI control group, indicating increased liver and kidney damage in rats subjected to combined blood flow occlusion and hepatectomy. HE staining showed clear liver tissue structure with intact and orderly arranged cells in the sham operation group, while the experimental groups exhibited cell structure damage, including cell rupture or collapse, cell swelling, nuclear pyknosis, deep cytoplasm staining, cell shedding, and necrosis. The interstitium showed infiltration of inflammatory cells. Immunohistochemical staining revealed a higher number of macrophages in the experimental groups compared to the sham operation group. CONCLUSIONS Four models of liver IRI in rat were successfully established. As the duration and severity of hepatic ischemia increased, liver cell ischemia worsened, leading to increased hepatocellular necrosis and exhibiting characteristic features of liver IRI. These models can effectively simulate liver IRI following liver trauma, with the group subjected to 100% ischemia and 30% hepatectomy showing the most severe liver injury. The designed models are reasonable, easy to perform, and exhibit good reproducibility. They can be used for investigating the mechanisms, therapeutic efficacy, and diagnostic methods related to clinical liver IRI.
Rats ; Male ; Animals ; Reproducibility of Results ; Rats, Sprague-Dawley ; Liver ; Reperfusion Injury/drug therapy* ; Ischemia ; Disease Models, Animal ; Necrosis

Objective:To investigate the significance of multicolor flow cytometry (MFC) monitoring of minimal residual disease (MRD) in the course of allogeneic hematopoietic stem cell transplantation (allo-HSCT) after CD19-chimeric antigen receptor(CAR)-T cell immunotherapy for patients with refractory, relapsed B-cell acute lymphoblastic leukemia (r/r B-ALL).Methods:37 patients with r/r B-ALL admitted to Hebei Yanda Lu Daopei Hospital from January to July 2019, aged 15 (6, 19) years old, including 24 males and 13 females, were treated with CD19-CAR-T cell immunotherapy bridging allo-HSCT. MFC with cytoplasmic CD79a antibody to set up B-cell gates was used to monitor patients′ bone marrow (BM), cerebrospinal fluid (CSF), and tissue samples on day 0 (prior to the CAR-T cell immunotherapy), day 15, day 28 post CAR-T cell immunotherapy, and post transplantation.The MRD values of these samples were analyzed to evaluate the residual tumor cells and metastasis. The killing effect of the CAR-T cells was evaluated by the recovery of CD19+B cells before transplantation and the period between the timepoint when CD19+B cells was recovered and the timepoint when CAR-T cells were infused. Peripheral blood CAR-T cells were counted at different time points. Statistic analysis was performed by Kaplan-Meie assay and Log-rank test to analyze the difference of univariate cumulative survival.Results:(1)Among the 37 patients, 8 died and 29 survived. 5 patients relapsed after transplantation, of which 4 relapsed patients died and 1 survived. (2)MFC MRD negative remission rate of the death group was lower than that of the survival group at the following time points: post-CAR-T therapy and prior to transplantation (5/8 vs. 28/29, χ 2=7.540, P=0.006); day 15 of the CAR-T cell reinfusion (3/8 vs. 24/29, χ 2=6.512, P=0.011); day 28 of the reinfusion (3/8 vs. 276/29, χ 2=10.065, P=0.002). The probability of extramedullary MFC MRD positive tumor infiltration in the death group was higher than that in the survival group(7/8 vs. 14/29, χ 2=3.931, P=0.047). After CAR-T cell immunotherapy, the recovery period of CD19-positive cells in the death group, or the time for CAR-T cells to kill CD19-positive cells, was shorter than that in the survival group [42.00 days(30.00,49.00) vs. 55.00 days(41.50,73.50), Z=0.022, P=0.020]. Conclusion:The positive results of MRD by MFC at the following timepoints may predict unfavorable outcomes, such as post-CAR-T therapy and prior to transplantation, day 15 and 28 of the CAR-T cell immunotherapy, which may provide some guidance for clinical management.

Objective:To explore the status and obstacle factors of exercise in elderly maintenance hemodialysis (MHD) patients, so as to provide a clinical evidence for exercise guidance and targeted intervention in elderly maintenance hemodialysispatients.Methods:A mixed method of consistent parallel design was adopted. A total of 180 elderly MHD patients in two ClassⅢ hospitals of Kunshan in December 2021 were enrolled using convenience sampling method and investigated by questionnaire. The statas of exercise and exercise self-efficacy were researched. Objective sampling method was used to interview 17 elderly MHD patients with semi-structured interviews. The obstacle factors of exercise were investigated.Results:A total of 180 valid questionnaires were collected in the quantitative study. The highest metabolicequivalent of leisure time physical activity was 1 188 MET-min/w, the lowest was 0 MET-min/w, and the median was 396 MET-min/w. Pearson correlation analysis showed that there was a positive correlation between exercise self-efficacy and physical activity in elderly MHD patients ( P<0.05). Qualitative study extracted 3 themes and 9 subthemes, including lack of exercise knowledge, low self-efficacy, family and social environment resource limitation. Conclusions:Elderly MHD patients lack ideal exercise state. In clinical practice, medical staff should popularize exercise knowledge, improve patients' exercise self-efficacy, carry out family support education, increase social support, and select suitable exercise methods and develop individualized exercise programs according to patients' disease characteristics, so as to improve their exercise status.

Objective:This study aims to analyze the counts (per kilogram of body weight) or percentages of transplanted lymphocyte subgroups in children with non-infectious pulmonary complications (NIPC) and air-leak syndrome (ALS) after allogeneic hematopoietic stem cell transplantation (allo-HSCT) and explore its significance in the progression of lung complications after transplantation.Methods:The patients with NIPC and ALS after allo-HSCT from January 2013 to December 2019 in Hebei Yanda Ludaopei Hospital were retrospectively studied and the influencing factors in the progress of NIPC after HSCT were statistically analyzed.Results:Of the 2026 children who received HSCT treatment, 59 patients (34 males and 25 females) developed NIPC, the probability was 2.9% (59/2 026), and the probability of combined ALS was 1.4% (28/206). The differences in the comparison between NIPC progressed to ALS group (ALS group) and failed to progress to ALS group (non-ALS group) in the patient′s age( P=0.028), disease condition before transplantation( P=0.022), NIPC onset time( P=0.004) were significant. The P values of the percentage of NKT-like cells in the bone marrow ( P=0.008) or peripheral stem cells ( P=0.003) accounted for the lymphocytes. CD4+CD25+dim cells in bone marrow ( P=0.029) or peripheral stem cells ( P=0.036) accounted for the CD4+lymphocytes and the ratio of CD4/CD8 in bone marrow( P=0.004) or peripheral stem cells ( P=0.020) were less than 0.05, which meant the differences in patients′ refusion cells were significant. In the binary logistic regression model, the percentage of bone marrow NKT-like cells to lymphocytes, the ratio of bone marrow CD4+/CD8+and the percentage of peripheral stem NK cells to lymphocytes were important risk factors for the progression of NIPC to ALS. The rest factors were excluded from the model (AUC=0.918, P<0.05). Conclusion:During allo-HSCT transplantation, a high proportion of NKT-like cell and NK cell levels, and a high CD4+/CD8+ratio in the infusion of donors with high immune tolerance have an important correlation with the progression of the NIPC.