BACKGROUND: Ischemic postconditioning protects the myocardium from ischemia/recursion injury via maintaining 3-minute acidosis initially. But its effect on the skeletal muscle remains unclear. OBJECTIVE: To dynamically measure the pH values in rat skeletal muscle after ischemia, and then to simulate acidic perfusate infusion to investigate the effect of ischemic postconditioning on ischemia/reperfusion injury. METHODS: Based on the ischemia/reperfusion injury model and ischemic postconditioning protocol in previous study, dynamic measurement of pH values in rat skeletal muscle was conducted using pH instrument at the global ischemia, ischemic postconditioning (30/30 seconds) and reperfusion period, and then the acidic perfusate equivalent to pH in ischemic postconditioning period was prepared with lactic acid and normal saline. Twenty-five healthy adult male Sprague-Dawley rats were randomly divided into sham, ischemia/reperfusion, ischemic postconditioning, lactic acid, and normal saline groups (n=5 per group). Blood samples were collected to detect lactate dehydrogenase level. The samples from gastrocnemius were harvested to calculate the wet/dry ratio, level of myeloperoxidase, and infarct size through triphenyltetrazolium chloride staining. The samples from the right tibialis anterior muscle were taken to detect the expression level of Erk1/2 in the MAPK signaling pathway by western blot assay. RESULTS AND CONCLUSION: A prolonged acidic platform was detected in the early reperfusion during ischemic postconditioning, on which the pH value was 6.81±0.133, and the duration was 2 minutes and 40 seconds. The levels of lactate dehydrogenase and myeloperoxidase as well as the wet/dry ratio in the ischemic postconditioning and lactic acid groups were significantly lower than those in the ischemia/reperfusion group (P < 0.05). Western blot assay results showed that the expression level of p-Erk in the ischemic postconditioning, lactic acid and normal saline groups was significantly higher than that in the ischemia/reperfusion group (P < 0.05). Triphenyltetrazolium chloride staining results showed that compared with the ischemia/reperfusion group, the infarct area was significantly reduced in the postconditioning and lactic acid groups (P < 0.05). These findings suggest the existence of a short acidosis during ischemic postconditioning in the early reperfusion, and acidic perfusate can simulate the ischemic postconditioning and effectively attenuate ischemia/reperfusion injury in the rat skeletal muscle via activating Erk1/2 in RISK signaling pathway.

ObjectiveTo investigate the feasibility and safety of endoscopic retrograde cholangiopancreatography （ERCP） combined with oral cholangiopancreatography in the treatment of major duodenal papilla gallbladder polyps. MethodsA retrospective analysis was performed for the clinical data of eight patients with choledocholithiasis and gallbladder polyps who underwent ERCP and combined with oral cholangiopancreatography for major duodenal papilla cholecystectomy in Center of Digestive Endoscopy， Jilin People’s Hospital， from May 2022 to June 2024， and related data were collected， including the success rate of surgery， the technical success rate of gallbladder polyp removal， the superselective method of cystic duct， the time of operation， the time of gallbladder polyp removal， and surgical complications. ResultsBoth the success rate of surgery and the technical success rate of gallbladder polyp removal reached 100%， and of all eight patients， three patients used guide wire to enter the gallbladder under direct view， while five patients received oral cholangiopancreatography to directly enter the gallbladder. The time of operation was 51.88±12.34 minutes， and the time of gallbladder polyp removal was 23.13±10.94 minutes. The diameter of gallbladder polyp was 2‍ ‍—‍ ‍8 mm， and pathological examination showed inflammatory polyps in three patients， adenomatous polyps in one patient， and cholesterol polyps in four patients. There were no complications during or after surgery. The patients were followed up for 2‍ ‍—‍ ‍27 months after surgery， and no recurrence of gallbladder polyp was observed. ConclusionOral cholangiopancreatography is technically safe and feasible in endoscopic major duodenal papilla cholecystectomy.

OBJECTIVETo culture osteoblast in vitro and evaluate CCL3 receptor CCR1 expression in patients with multiple myeloma (MM).

METHODSBone marrow osteoblasts from MM patients were cultured in vitro with dexamethasone, β-sodium glycerophosphate and vitamin C, which were identified by alkaline phosphatase staining, Von Kossa's staining. The CCL3 receptor expression was evaluated by flow cytometry. The morphology and quantity of osteoblast were observed after exposure to CCL3.

RESULTSBone marrow osteoblasts from MM patients could be cultured in vitro and be identified by positive staining of alkaline phosphatase and Von Kossa's. MM-derived osteoblasts expressed higher levels of CCR1 (74.48 ± 7.31)%, compared with normal controls (48.35 ± 8.81)%. Calcium deposition of osteoblasts after exposure to CCL3 was less than that of controls.

CONCLUSIONBone marrow osteoblasts could be cultured in vitro from MM Patients. CCL3 may contribute to the development of myeloma bone disease.

Adult ; Aged ; Cells, Cultured ; Chemokine CCL3 ; pharmacology ; Female ; Humans ; Male ; Middle Aged ; Multiple Myeloma ; pathology ; Osteoblasts ; cytology ; drug effects ; metabolism ; Receptors, CCR1 ; metabolism ; Young Adult