OBJECTIVE: To investigate the biomechanical characteristics of retrograde tibial nailing (RTN) and distal tibial L-shaped plating in the internal fixation of distal tibial fractures. METHODS: Fourteen fresh adult tibia specimens were selected, comprising 7 males and 7 females aged from 34 to 55 years old. The specimens were randomly divided into experimental group and control group by numerical table method with 7 specimens in each group. RTN was used for internal fixation of distal tibial fractures in the experimental group, and L-shaped plate was used for internal fixation of distal tibial fractures in the control group. The axial compression properties of the two groups of specimens were tested under the pressure of 100, 200, 300, 400, and 500 N after operation, and torsional resistance at torque levels of 1.0, 2.0, 3.0, 4.0, 5.0 N·m. The anti-fatigue performance of the specimens was tested at 500 N pressure for 3 000 and 10 000 cycles. X-ray fluoroscopy was performed to observe whether the the internal fixator was deformed and whether the screw was loosened or broken. RESULTS: When the pressure was 400 N and 500 N, the axial compression displacement of the experimental group was (1.11±0.06) mm and (1.24±0.05) mm, which were smaller than those of the control group (1.21±0.08) mm and (1.37±0.11) mm, and the differences were statistically signific (P<0.05). Under the pressure of 500 N, the axial compression stiffness of the experimental group was (389.24±17.79) N·mm^-1, which was significantly higher than that of the control group (362.37±14.44) N·mm^-1(P<0.05). When the torque was 4 and 5 N·m, the torsion angles of the experimental group were (2.97±0.23) ° and (3.41±0.17) °, which were smaller than those of the control group (3.31±0.28) ° and (3.76±0.20) °, and the differences were statistically significant (P<0.05). When the torque was 5 N·m, the torsional stiffness of the experimental group was (1.48±0.07) N·m per degree, which was higher than that of the control group (1.36±0.06) N·m per degree, and the difference was statistically significant (P<0.05). For the intragroup comparison of fatigue resistance, the differences in axial compression displacement between the two groups were not statistically significant at 3 000 and 10 000 cycles (all P>0.05). When 3 000 times and 10 000 times of compression, the axial compression displacement of the experimental group was (1.38±0.08), (1.43±0.07) mm, which was smaller than that of the control group (1.51±0.10), (1.54±0.08) mm, the differences were statistically significant (P<0.05). In the experimental group, no screw loosening, fracture or internal fixation deformation was found, while in the control group, locking screw loosening occurred in 2 models after 10 000 pressures. CONCLUSION The biomechanical performance of RTN is obviously better than that of the distal tibial L-shaped plate, which provides biomechanical data support for the clinical application of RTN.
Humans ; Female ; Male ; Adult ; Tibial Fractures/physiopathology* ; Middle Aged ; Biomechanical Phenomena ; Bone Plates ; Fracture Fixation, Internal/instrumentation* ; Bone Nails ; Tibia/surgery*

Testicular histology based on testicular biopsy is an important factor for determining appropriate testicular sperm extraction surgery and predicting sperm retrieval outcomes in patients with azoospermia. Therefore, we developed a deep learning (DL) model to establish the associations between testicular grayscale ultrasound images and testicular histology. We retrospectively included two-dimensional testicular grayscale ultrasound from patients with azoospermia (353 men with 4357 images between July 2017 and December 2021 in The First Affiliated Hospital of Sun Yat-sen University, Guangzhou, China) to develop a DL model. We obtained testicular histology during conventional testicular sperm extraction. Our DL model was trained based on ultrasound images or fusion data (ultrasound images fused with the corresponding testicular volume) to distinguish spermatozoa presence in pathology (SPP) and spermatozoa absence in pathology (SAP) and to classify maturation arrest (MA) and Sertoli cell-only syndrome (SCOS) in patients with SAP. Areas under the receiver operating characteristic curve (AUCs), accuracy, sensitivity, and specificity were used to analyze model performance. DL based on images achieved an AUC of 0.922 (95% confidence interval [CI]: 0.908-0.935), a sensitivity of 80.9%, a specificity of 84.6%, and an accuracy of 83.5% in predicting SPP (including normal spermatogenesis and hypospermatogenesis) and SAP (including MA and SCOS). In the identification of SCOS and MA, DL on fusion data yielded better diagnostic performance with an AUC of 0.979 (95% CI: 0.969-0.989), a sensitivity of 89.7%, a specificity of 97.1%, and an accuracy of 92.1%. Our study provides a noninvasive method to predict testicular histology for patients with azoospermia, which would avoid unnecessary testicular biopsy.
Humans ; Male ; Azoospermia/diagnostic imaging* ; Deep Learning ; Testis/pathology* ; Retrospective Studies ; Adult ; Ultrasonography/methods* ; Sperm Retrieval ; Sertoli Cell-Only Syndrome/diagnostic imaging*

Objective To investigate the effect and mechanism of hypericin on osteoporosis(OP)in rats with chronic obstructive pulmonary disease(COPD).Methods COPD combined with OP rat model was established by cigarette combined with bacteria.The rats were randomly divided into control group,model group(COPD combined with OP model was constructed),experimental-L group(50 mg·kg-1 hypericin was given by intragastric administration after constructing COPD combined with OP model),experimental-H group(100 mg·kg-1 hypericin was given intragastric administration after constructing COPD combined with OP model),positive group(subcutaneous injection of 16 U·kg-1 salmon calcitonin after constructing COPD combined with OP model);each group was given 12 rats for 90 days.The lung function of rats was detected by pulmonary function apparatus;bone mineral density(BMD)was detected by micro-computed tomography(CT);serum bone metabolism and inflammatory factors were detected by enzyme-linked immunosorbent assay(ELISA);Western blot assay was used to detect the relevant indicators of the pathway.Results The levels of forced vital capacity(FVC)in control group,model group,experimental-H group and positive group were(10.42±1.40),(4.10±0.60),(6.75±0.37),(4.18±0.33)mL,respectively;BMD levels were(0.31±0.04),(0.12±0.02),(0.28±0.03),(0.29±0.04)g·mm-3,respectively;bone alkaline phosphatase(BALP)levels were(200.04±20.03),(80.80±6.00),(148.16±14.23),(173.97±23.55)U·L1,respectively;interleukin-1β(IL-1β)levels were(122.60±8.70),(695.59±74.84),(422.41±44.86),(527.90±39.36)pg·mL-1,respectively;phosphorylated p38 mitogen-activated protein kinase(p-P38)protein expression levels were 0.99±0.11,0.36±0.05,0.79±0.08,0.36±0.04,respectively.Compared with the control group,the above indexes in the model group had statistical significance(all P＜0.05);the above indexes in experimental-H group were significantly different from those in model group(all P＜0.05).Conclusion Hypericin can inhibit inflammatory response,improve bone metabolism and biomechanics.

Objective To analyze the effects of different anastomotic methods on flap survival rate and wound healing factors of patients with transplantation of superficial branch perforator flap of superficial circumflex iliac artery(SCIA).Methods A total of 100 patients with skin defects of limbs admitted to our hospital from January 2019 to August 2022 were selected and divided into end-to-end anastomosis group(56 cases)and end-to-side anastomosis group(44 cases)according to different anastomosis methods.In the end-to-end anastomosis group,the end of the flap artery was anastomosed with the end of the aortic branch in the affected area.In the end-to-side anastomosis group,the end of recipient flap artery was anastomosed with the side of aorta.Patients in both groups were followed up for 6 to 12 months,the arterial caliber,lateral caliber and anastomosis time were compared between the two groups.The survival of the flap,the occurrence of venous crisis,the shape and function of the flap and donor area were observed.Results There was no statistically significant difference in the arterial caliber or lateral caliber of patients between the two groups(P>0.05).The anastomosis time of patients in the end-to-end anastomosis group was significantly shorter than that in the end-to-side anastomosis group(P<0.05).All 56 cases in the end-to-end anastomosis group survived.In the end-to-side anastomosis group,venous crisis occurred in 4 cases,with venous thrombosis,2 cases survived after re-anastomosis,2 cases were changed to abdominal pedicled flap when venous crisis occurred again,the appearance and function of the flap and donor area were satisfactory 6 months to 1 year after surgery(P<0.05).There was no significant difference in color,thickness,vascular distribution or flexibility of donor area of patients between the two groups(P>0.05).There was no significant difference in pain,appearance,vitality and recreation of recipient area of patients between the two groups(P>0.05).Conclusion The application of different arterial anastomosis methods in the transplantation of superficial branch perforator flap of SCIA for the treatment of skin and soft tissue defects of limbs is safe and reliable,the postoperative survival of the flap is good,the healing is not affected by the anastomosis method,and the appearance of the affected area is satisfactory,which is worthy of clinical promotion.

Objective:To assess the clinical value of helium-free magnetocardiography(MCG) in the diagnosis of coronary artery disease(CAD).Methods:A total of 213 patients with suspected CAD undergoing MCG in Beijing Anzhen Hospital were enrolled in the study. All patients underwent coronary CT angiography/invasive coronary angiography(CCTA/ICA) within 48 hours after MCG scanning. The parameters of MCG, including magnetic field multipolarization, magnetic field unipolarization, T-wave flattened, change in magnetic field distribution at TT segment, abnormal T-peak amplitude ration of maximum to minimum, significant movement of poles, magnetic field angle deviation and abnormal distribution of positive pole were used for the evaluation of the stenosis of coronary arteries.Results:Among 213 patients, MCG scanning was completed in 193 cases(90.6%), while 20 cases were excluded for various reasons. The CCTA/ICA results were taken as gold standard, the total coincidence rate of MCG with the degree of stenosis was 88.60%(95% CI: 83.25%-92.72%), the sensitivity and specificity of MCG in the diagnosis of CAD was 89.63%(95% CI: 83.21%-94.21%) and 88.23%(95% CI:78.12%-94.78%), respectively; the positive and negative predictive value were 93.80%(95% CI:88.72%-96.68%) and 81.08%(95% CI:72.15%-87.64%), respectively. Conclusion:MCG is highly accurate in the diagnosis of CAD, it may be widely used clinically as an non-invasive method free of radiation or contrast agent.

OBJECTIVE To establish characteristic HPLC chromatograms for Jubei mixture, and to simultaneous determine its six components by HPLC-ELSD. METHODS An HPLC specific chromatogram of the Jubei mixture was established. The chromatographic column was Agilent ZORBAX-C18(250 mm×4.6 mm, 5 μm), gradient elution was conducted with acetonitrile(A)-0.1% phosphoric acid aqueous solution(B) as the mobile phase, the flow rate was 1.0 mL·min-1, and the column temperature was 30℃, the detection wavelength was 250 nm. An HPLC-ELSD method was established and the chromatography was accomplished on a Waters T3 C18(250 mm×4.6 mm, 5 μm) column, the mobile phase consisted of acetonitrile(A)-1% acetic acid aqueous solution(B) in a gradient mode, the flow rate was 1.0 mL·min-1, the column temperature was set at 30℃. RESULTS The characteristic chromatograms of the HPLC with baicalin as the reference peak was established, and eight common peaks were defined. The linear ranges of amygdalin, liquiritin, peimine, peiminine, platycodin D and ophiopogonin D were good within their own ranges(r ≥ 0.999). The average recovery were 99.1%, 98.6%, 100.9%, 97.7%, 98.9% and 98.0%, RSD were 0.4%, 1.0%, 1.1%, 1.2%, 0.7% and 1.3%, respectively. CONCLUSION The established methods can be used to qualitative identification and quantitative determination of Jubei mixture, can effectively used for evaluation and quality control of Jubei mixture.

COVID-19 has been prevalent for three years. The virulence of SARS-CoV-2 is weaken as it mutates continuously. However, elderly patients, especially those with underlying diseases, are still at high risk of developing severe infections. With the continuous study of the molecular structure and pathogenic mechanism of SARS-CoV-2, antiviral drugs for COVID-19 have been successively marketed, and these anti-SARS-CoV-2 drugs can effectively reduce the severe rate and mortality of elderly patients. This article reviews the mechanism, clinical medication regimens, drug interactions and adverse reactions of five small molecule antiviral drugs currently approved for marketing in China, so as to provide advice for the clinical rational use of anti-SARS-CoV-2 in the elderly.

Objective: To investigate the association between the urinary arsenic level and serum total testosterone in Chinese men aged 18 to 79 years. Methods: A total of 5 048 male participants aged 18 to 79 years were recruited from the China National Human Biomonitoring (CNHBM) from 2017 to 2018. Questionnaires and physical examinations were used to collect information on demographic characteristics, lifestyle, food intake frequency and health status. Venous blood and urine samples were collected to detect the level of serum total testosterone, urinary arsenic and urinary creatinine. Participants were divided into three groups (low, middle, and high) based on the tertiles of creatinine-adjusted urinary arsenic concentration. Weighted multiple linear regression was fitted to analyze the association of urinary arsenic with serum total testosterone. Results: The weighted average age of 5 048 Chinese men was (46.72±0.40) years. Geometric mean concentration (95%CI) of urinary arsenic, creatinine-adjusted urinary arsenic and serum testosterone was 22.46 (20.08, 25.12) μg/L, 19.36 (16.92, 22.15) μg/g·Cr and 18.13 (17.42, 18.85) nmol/L, respectively. After controlling for covariates, compared with the low-level urinary arsenic group, the testosterone level of the participants in the middle-level group and the high-level group decreased gradually. The percentile ratio (95%CI) was -5.17% (-13.14%, 3.54%) and -10.33% (-15.68%, -4.63). The subgroup analysis showed that the association between the urinary arsenic level and testosterone level was more obvious in the group with BMI<24 kg/m² group (P_interaction=0.023). Conclusion: There is a negative association between the urinary arsenic level and serum total testosterone in Chinese men aged 18 to 79 years.
Humans ; Male ; Arsenic/urine* ; Creatinine ; East Asian People ; Testosterone/blood* ; Urinalysis ; Adolescent ; Young Adult ; Adult ; Middle Aged ; Aged

Objective: To identify the main metals involved in cognitive impairment in the Chinese oldest old, and explore the association between these metal exposures and cognitive impairment. Methods: A cross-sectional study was conducted on 1 568 participants aged 80 years and older from Healthy Aging and Biomarkers Cohort Study (2017 to 2018). Fasting venous blood was collected to measure the levels of nine metals (selenium, lead, cadmium, arsenic, antimony, chromium, manganese, mercury, and nickel). The cognitive function of these participants was evaluated by using the Chinese version of the Mini-Mental State Examination (CMMSE). The random forest (RF) was applied to independently identify the main metals that affected cognitive impairment. The multivariate logistic regression model and restricted cubic splines (RCS) model were used to further verify the association of the main metals with cognitive impairment. Results: The age of 1 568 study subjects was (91.8±7.6) years old, including 912 females (58.2%) and 465 individuals (29.7%) with cognitive function impairment. Based on the RF model (the out-of-bag error rate was 22.9%), the importance ranking of variables was conducted and the feature screening of five times ten-fold cross-validation was carried out. It was found that selenium was the metal that affected cognitive function impairment, and the other eight metals were not included in the model. After adjusting for covariates, the multivariate logistic regression model showed that with every increase of 10 μg/L of blood selenium levels, the risk of cognitive impairment decreased (OR=0.921, 95%CI: 0.889-0.954). Compared with the lowest quartile(Q₁) of blood selenium, the ORs (95%CI) of Q₃ and Q₄ blood selenium were 0.452 (0.304-0.669) and 0.419 (0.281-0.622) respectively. The RCS showed a linear dose-response relationship between blood selenium and cognitive impairment (P_nonlinear>0.05). Conclusion: Blood selenium is negatively associated with cognitive impairment in the Chinese oldest old.
Aged, 80 and over ; Female ; Humans ; Selenium ; Cohort Studies ; Cross-Sectional Studies ; Metals/analysis* ; Cognitive Dysfunction/epidemiology* ; China/epidemiology*

Objective: To evaluate the effectiveness of a risk-adapted colorectal cancer screening strategy constructed utilizing genetic and environmental risk score (ERS). Methods: A polygenic risk score (PRS) was constructed based on 20 previously published single nucleotide polymorphisms for colorectal cancer in East Asian populations, using 2 160 samples with MassARRAY test results from a multicenter randomized controlled trial of colorectal cancer screening in China. The ERS was calculated using the Asia-Pacific Colorectal Screening Score system. Logistic regression was used to analyze the association between PRS alone and PRS combined with ERS and colorectal neoplasms risk, respectively. We also designed a risk-adapted screening strategy based on PRS and ERS (high-risk participants undergo a single colonoscopy, low-risk participants undergo an annual fecal immunochemical test, and those with positive results undergo further diagnostic colonoscopy) and compared its effectiveness with the all-acceptance colonoscopy strategy. Results: The high PRS group had a 26% increased risk of colorectal neoplasms compared with the low PRS group (OR=1.26, 95%CI: 1.03-1.54, P=0.026). Participants with the highest PRS and ERS were 3.03 times more likely to develop advanced colorectal neoplasms than those with the lowest score (95%CI: 1.87-4.90, P<0.001). As the risk-adapted screening simulation reached the third round, the detection rate of the PRS combined with ERS strategy was not statistically different from the all-acceptance colonoscopy strategy (8.79% vs. 10.46%, P=0.075) and had a higher positive predictive value (14.11% vs. 10.46%, P<0.001) and lower number of colonoscopies per advanced neoplasms detected (7.1 vs. 9.6, P<0.001). Conclusion: The risk-adapted screening strategy combining PRS and ERS helps achieve population risk stratification and better effectiveness than the traditional colonoscopy-based screening strategy.
Humans ; Early Detection of Cancer ; Risk Factors ; Colorectal Neoplasms/genetics* ; Asia ; China/epidemiology*