OBJECTIVETo compare the effects of oral treatment with tetrandrine (TD) and N-acetylcys-teine (NAC) separately or jointly on silica-exposed rats.

METHODS40 sprague-Dawly (SD) rats were randomly divided into normal saline group, quartz group, TD treatment group (50 mg/kg), NAC treatment group (500 mg/kg) and combined treatment group (TD: 50 mg/kg + NAC: 500 mg/kg). Rats in normal saline group and other groups received intratracheal instillation of normal saline and quartz dust suspension respectively. Treatment groups were given TD, NAC separately or jointly via esophagus the next day after instillation, once a day and six times a week for 30 consecutive days. At the end of experiment, the pathological changes of lung tissues were evaluated by the methods of Foot, HE and Masson staining, the level of hydroxyproline (HYP), malondjalde-hyde (MDA), tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) in lung tissues were measured by alkaline hydrolysis method, the barbituric acid method and enzyme-linked immunosorbent assay (ELISA) respectively.

RESULTSCompared with the quartz group, lymph nodes/body coefficients in all treatment groups and lung/body coefficient in combined treatment group were significantly decreased (P < 0.05). Pathology results showed that the normal saline group demonstrated no obvious evidence of lung damage. The quartz group lungs silicotic lesions focused on II~III level, the TD treatment group was mainly with I level, the NAC treatment group was mainly with I~II level, and the combined treatment group only showed little silicotic nodule, no obvious fibrosis. HYP content in TD treatment group and combined treatment group were significantly lower than that in the quartz group (P < 0.05), while it showed no obvious change in NAC treatment group. MDA content in lung tissues of each treatment group (TD treatment group, NAC treatment group and combined treatment group) were 18.80 ± 2.94, 20.13 ± 4.01 and 17.05 ± 3.52 nmol/ml respectively, which lower than in the quartz group (23.99 ± 3.26 nmol/ml). The level of IL-6 in lung tissues of the quartz group were 89.57 ± 8.78 pg/ml. After TD and NAC monotherapy, the IL-6 content decreased to 79.22 ± 9.65 pg/ml and 81.63 ± 5.72 pg/ml, and it decreased more significantly after combined medication (74.37 ± 3.17 pg/ml). The level of TNF-α in the quartz group were 59.05 ± 4.48 pg/ml. After TD and NAC monotherapy, the TNF-α content decreased to 50.48 ± 2.76 pg/ml and 54.28 ± 4.30 pg/ml, and it decreased more significantly after combined medication (49.10 ± 4.98 pg/ml).

CONCLUSIONNAC and TD could reduce MDA, TNF-α and IL-6 levels in lung tissue, and alleviate SiO2-induced pulmonary fibrosis in rats. Combined treatment with TD and NAC was more effective than TD or NAC treatment separately.

Acetylcysteine ; pharmacology ; Animals ; Benzylisoquinolines ; pharmacology ; Disease Models, Animal ; Dust ; Hydroxyproline ; metabolism ; Interleukin-6 ; metabolism ; Lung ; pathology ; Malondialdehyde ; metabolism ; Pulmonary Fibrosis ; chemically induced ; drug therapy ; Quartz ; toxicity ; Rats ; Rats, Wistar ; Silicon Dioxide ; toxicity ; Silicosis ; drug therapy ; Tumor Necrosis Factor-alpha ; metabolism

Objective:To evaluate the efficacy of roxatidine and omeprazolein on preventing gastrointestinal bleeding in critically ill patients.Methods:A prospective cohort study was conducted in adult patients admitted to an intensive care unit (ICU), who had risk factors for stress related mucosal disease (SRMD), and had an estimated stay of no less than 5 days and mechanical ventilation for more than 48 h. Patients were randomized into the experiment group (Roxatidine 75 mg IV Q12 h) and control group (Omeprazole 40 mg IV Q12 h). Demographic data, acute physiology and chronic health score (APACHEⅡ) and SOFA score on day 1 were collected, intragastric pH values were tested every 2 hours for the first 5 days, the daily average of pH and proportion of patients with average pH≥4 were calculated. Stool occult blood were detected at day 1 and bacterial culture of gastric juice were performed before medication administration and on day 5 after medication administration. The implementation of enteral nutrition support, situation of gastrointestinal hemorrhage and adverse effects were analyzed. Furthermore, length of hospital stay and mortality in ICU and on the 28th day were acquired. SPSS 22.0 software was used for data analysis. Consecutive data were expressed as mean and standard deviation, categorical data were expressed as frequencies (percentage). Comparison of measurement data between groups was performed by analysis of variance or rank sum test. Comparison of count data between groups was performed by the Chi-square test. P<0.05 was regarded as statistically significant. Results:A total of 91 patients were recruited and randomly separated into experimental group ( n=46) and control group ( n=45) from October 2017 to March 2018. There were no statistical differences in gender, age, body mass index (BMI), enteral nutrition status, APACHEⅡ and SOFA score on day 1 between the two groups (all P>0.05). Roxatidine in the experiment group rapidly increased the intragastric pH to ≥4.0 and continued to stabilize at pH ≥4.0 during the monitoring period. Omeprazole increased and maintained intragastric pH≥5.0. The proportion of patients with average pH≥4.0 was 82.5% in the second 24 hours in the experiment group, and stably increased to 90% on day 5. There were no significant differences between groups in gastrointestinal bleeding, length of hospital stay, and mortality in ICU and on 28th day(all P> 0.05). No drug related adverse effects occurred during the study period. Logistic-regression analysis did not screen for risk factors of SRMD. Conclusions:Roxatidine acetate hydrochloride can rapidly elevate and maintain the gastric pH above 4.0, and has similar efficacy and safety as omeprazole in inhibiting gastric acid secretion and preventing SRMD with gastrointestinal bleeding.

Objective:To explore the early effects and safety of using a hybrid fixation strategy with 3D-printed porous tantalum metal augments to reconstruct substantial bone defects in complex primary total knee arthroplasty (TKA).Methods:A retrospective analysis was performed on the clinical data from August 2019 to September 2023, encompassing 20 patients (21 knees) with significant bone loss who underwent hybrid fixation with 3D-printed porous tantalum augments. The procedures were conducted at two medical centers: the First Affiliated Hospital, School of Medicine, Zhejiang University (11 cases) and Xiangya Hospital of Central South University (9 cases). The study cohort comprised 6 males (6 knees) and 14 females (15 knees), with a mean age of 61.05±11.23 years (range, 42-80 years). The distribution of cases was 7 on the left side and 14 on the right side. All cases were categorized as type 3 according to the Anderson Orthopaedic Research Institute (AORI) classification system. The cohort included 19 unilateral and 1 bilateral case, with 5 involving complex primary replacements (3 with Charcot arthropathy, 1 with syphilitic arthropathy, and 1 with severe valgus deformity) and 16 revision surgeries (13 for aseptic loosening and 3 for infection). Preoperative assessments included routine CT scans and digital three-dimensional reconstructions to identify large metaphyseal defects exceeding 50% of the metaphyseal area or those thicker than 10 mm. For such defects, 3D-printed standardized porous tantalum augments were implemented. In cases of extensive cavitary bone defects or severe metaphyseal defects where the medial and lateral defects collectively exceeded 80% of the metaphyseal region or where the residual bone stock was insufficient for screw fixation of standardized augments, 3D-printed personalized custom-made porous tantalum augments were employed for hybrid fixation and repair. Comparative analyses were conducted on pre- and postoperative imaging data (prosthesis positioning and complications), knee range of motion (ROM), visual analogue scale (VAS) for pain, and Knee Society score (KSS).Results:Of the cases, 17 were repaired using standardized 3D-printed porous tantalum augments, while 4 underwent repairs with customized augments for hybrid fixation. Follow-up averaged 26.5±15.0 months (range, 12-62 months). There was a significant increase in knee ROM, improving from 72.8°±31.9° preoperatively to 113.2°±6.8° at 12 months postoperatively ( P<0.05). VAS scores decreased from 6.6±1.4 preoperatively to 2.5±1.0 at 12 months postoperatively ( P<0.05). Similarly, KSS improved from 52.8±6.4 preoperatively to 80.7±7.9 at 12 months postoperatively ( P<0.05). There were no incidences of prosthesis displacement, poor bone integration, or postoperative infections. Conclusion:The hybrid fixation strategy employing 3D-printed porous tantalum augments has been found to be effective in addressing significant bone defects in TKA. The follow-up results indicate a satisfactory biological integration of the porous tantalum metal augments with the host bone, which has resulted in substantial improvements in pain relief and knee joint functionality.