BACKGROUND: Femoral head necrosis can be induced in adult rabbits when a large dose of steroid has been used for a long time. However, the pathogenesis of steroid-induced femoral head necrosis needs further study.OBJECTIVE: To probe into the mechanism of the disease by light microscope and transmission microscope from morphological perspective based on the model of femoral head necrosis in rabbits.DESIGN: A randomized controlled observation.SETTING: Laboratory of Morphology; Teaching and Research Division of Pathology; Laboratory of Surgery, Weifang Medical College.MATERIALS: The experiment was carried out at the Experimental Center of Morphology, Weifang Medical College, between March 2002 and March 2003. Totally 40 adult New Zealand white rabbits were randomly divided into control group (n=10), dexamethasone group (n=10) and horse serum group (n=20).METHODS: Control group was given intravenous injection of normal saline of 10 mL/(kg·d) for 7 consecutive days. Dexamethasone group was given intramuscular injection of dexamethasone of 10 mL/(kg ·d)for 7consecutive days. Horse serum group was given intravenous administration of horse serum of 10 mL/kg; 3 weeks later the same volume of horse serum was injected once again, followed intramuscular injection of dexamethasone of 10 mL/(kg·d)for 7 consecutive days. Inferior sections of cartilage of the femoral head necrosis in the experimental animals were obtained 5 and 10weeks later, and then histological and ultrastructural changes were observed under the light microscope and transmission microscope.MAIN OUTCOME MEASURES: ① Histo-morphological observation of the animals in each group. ② Ultrastructural changes.RESULTS: All the experimental animals survived and entered the result analysis. ① Histo-morphological observation: The cells of inferior sections of cartilage of the femoral head necrosis of the experimental animals in control group were arranged regularly and had a small volume of elliptical bone cells. The cell body was located at bone lacuna, blood vessel arranged well in the medullary cavity of bone. Lesion haracteristics of femoral head in dexamethasone group and horse serum group were similar:Hematopoietic adipose in the medullary cavity of bone was significantly decreased while fat adipose obviously increased; bone trabecula of metaphysis and the inferior sections of cartilage of femoral head were found with ered, and so was the bone nucleus. The number of lacuna of bone was increased. ② Ultrastructural changes: Normal bone cells in control group were elliptical, located at bone lacuna. Nucleus was at one end of the cell with complete karyotheca and many mitochondria in the cytoplasm. In dexamethasone group and horse serum group there were lipid droplets in the osteocytes, narrowed blood capillary in the medullary cavity of bone and injured vascular endothelial cells.CONCLUSION: Corticotropin can induce necrosis of femoral head; the hormone causes accumulated fat adipose in the medullary cavity of bone.The increased internal pressure in the medullary cavity leads to ischemia of femoral head, thus inducing the necrosis of osteocytes.

Objective To analyze the clinical characteristics and prognostic risk factors of esophageal signet ring cell carcinoma(SRCC)patients and construct a column chart prediction model.Methods The training queue consists of 226 patients diagnosed with esophageal SRCC from 2010 to 2017 in the SEER database,and the validation queue consists of 21 patients diagnosed with esophageal SRCC in our hospital from January 2010 to January 2019.Use Cox proportional risk regression model for single factor and multivariate analysis.Use the"rms"software package of R software to generate column charts.Results Univariate analysis showed that age,gender,tumor location,local invasion,lymph node metastasis,distant metastasis,surgical treatment,chemotherapy,and radiotherapy were risk factors affecting the prognosis of SRCC patients(P＜0.05);In multivariate cox regression analysis,the results showed that tumor location,local invasion,lymph node metastasis,distant metastasis,surgical treatment,chemotherapy,and radiotherapy were independent risk factors affecting the prognosis of SRCC patients(P＜0.05);A nomogram prediction model was successfully constructed using multivariate cox regression analysis,with a certain degree of predictive accuracy.Conclusion The nomogram prediction model was successfully constructed based on the risk factors affecting the prognosis of esophageal signet ring cell adenocarcinoma patients in the SEER database,which can provide more accurate predictions for the prognosis of esophageal SRCC patients.

Objective:To evaluate the efficacy and safety of endoscopic retrograde cholangiopancreatography (ERCP) after pancreaticoduodenectomy and endoscopic selection strategies.Methods:Clinical data of 34 patients treated with ERCP after pancreaticoduodenectomy at the Endoscopic Center of the First Affiliated Hospital of Air Force Medical University from January 2013 to December 2021 were retrospectively analyzed. The success rates of endoscopic insertion, diagnosis, treatment and ERCP, and the incidence of adverse events were analyzed.Results:Fifty ERCP treatments were performed in 34 patients. The success rates of endoscopic insertion, diagnosis, treatment, and ERCP after pancreaticoduodenectomy were 92.0% (46/50), 93.5% (43/46), 88.4% (38/43) and 76.0% (38/50), respectively. The success rates of ERCP assisted with colonoscope and balloon-assisted enterosocpe were 76.0% (19/25) and 75.0% (18/24), respectively. There were 3 adverse events, including 1 case of anastomotic mucosa tear during surgery, 1 case of cardiopulmonary arrest and 1 case of postoperative cholangitis.Conclusion:ERCP is effective and safe after pancreaticoduodenectomy in general. ERCP assisted with colonoscope and balloon-assisted colonoscope shows similar success rate after pancreaticoduodenectomy.

Objective: To observe the effect of recombinant human growthhormone (r-hGH) on osteoporotic fracture healing in rats, and to provide an effective therapy for osteoporotic fracture.Methods: Thirty-six female 8-month-old SD rats were randomized into two groups: therapy group and control group. After the experimental model of osteoporotic fracture was established, the therapy group was treated with r-hGH of 2.7 mg/kg body weigh/day (1 mg=3 IU) for 10 days continuously by daily subcutaneous injection; whereas the control group was treated with equivalent saline. Plasma insulin-like growth factor I concentration was detected and bone mineral density (BMD) as well as biomechanical strength of callus were measured at 2, 4, 8 weeks.Results: Plasma insulin-like growth factor I concentration in the therapy group was higher than that in the control group (P<0.005) at 2nd week and began to decline at 4th week. At 8th week, there was no significant difference between the two groups. At 4th week, callus area and BMD in therapy group were higher than those in the control group, but at 8th week, they were lower and BMD had a significant difference between the two groups (P<0.001). Biomechanical testing of callus showed that torsional strength of the therapy group was higher than that of the control group at 4th or 8th week, meanwhile maximum torsional angle had a significant difference between the two groups (P<0.005).Conclusions: The results show that exogenous r-hGH can stimulate osteoporotic fracture healing in rats.