Fibronectin inhibits endocytosis of calcium oxalate crystals by renal tubular cells

BACKGROUND: Fibronectin (FN; 230 kDa) is a multifunctional alpha2-glycoprotein distributed throughout the extracellular matrix and body fluids. We recently reported that FN has a protective effect against injury of renal tubular cells by exposure to oxalate and calcium oxalate (CaOX) crystals and inhibits the adhesion of CaOX crystals to renal tubular cells. In the study presented here, we investigated whether FN has inhibitory effect on crystal endocytosis by renal tubular cells. METHODS: The inhibitory effect of FN on endocytosis of CaOX crystals by MDCK cells was examined by using a radioactivity uptake assay. Also, crystal endocytosis by cells was morphologically assessed by means of transmission electron microscopy (TEM). RESULTS: FN had inhibitory effects on CaOX crystal endocytosis by MDCK cells. The morphological TEM study showed that few crystals were taken into cells when FN was added compared to the number of crystals when FN was not added. CONCLUSION: We found that FN had the inhibitory effects on the interaction between crystals and renal tubular cells, including the adhesion or endocytosis of crystals by cells.     

Urinary macromolecules and renal tubular cell protection from oxalate injury: Comparison of normal subjects and recurrent stone formers

AIM: To determine whether urinary macromolecules (UMM), which are the high molecular weight substances in urine, can provide protection against the oxalate-associated injury to the renal tubular cells. METHODS: UMM were extracted from 24-h urine of 12 healthy adult male volunteers and 13 recurrent-stone-former male patients. Urine parameters in relation to urolithiasis were measured, including the level of glycosaminoglycans (GAG) in the UMM. Madin-Darby canine kidney (MDCK) cells were used to evaluate the protective activity of UMM from oxalate-induced cytotoxicity by LDH release measurement and methyl-thiazolyl tertrazolium (MTT) assay. RESULTS: Considering urinary parameters, citrate was significantly higher in urine from normal subjects than stone-former subjects; the other parameters show no differences between the groups. Total UMM and the level of GAG in the UMM were also significantly higher in the normal subject group. Compared with normal subject and stone-former subject UMM, after cells were treated with the UMM and then exposed to oxalate solution, LDH release was significantly higher in stone-former group. In the MTT assay, we found that more viable cells were observed after treatment with UMM compared to control in both groups. Moreover, UMM from the normal subjects showed higher protective activity against oxalate-related cytotoxicity than UMM from the stone-former subjects. CONCLUSION: UMM protected renal epithelial cells from oxalate-related injury. This protective activity was found to be higher in normal subject UMM than stone-former UMM. Among other factors, a higher concentration of GAG and citrate in normal subject UMM might affect some parts in this finding.     

Usefulness of the Adenosine Triphosphate with a Sufficient Observation Period for Detecting Reconduction after Pulmonary Vein Isolation

Background: Although reconduction after pulmonary vein (PV) isolation is considered to play a key role in the recurrence of paroxysmal atrial fibrillation (AF), there have been few reports regarding the precise time course of early reconduction. Several studies have suggested that transient PV reconduction facilitated by adenosine may predict long-term AF recurrence. This study was designed to clarify the incidence and time course of early reconduction after PVI during the procedure and to confirm whether the use of ATP after a certain observation period was useful to detect early reconduction after PVI.
Methods: In 21 patients (18 males, 56 ± 11 years) with drug refractory AF, radiofrequency circumferential PV antrum ablation was performed in all 4 PVs. After the completion of isolation, electrograms in each PV were repeatedly recorded (1.98 ± 0.57 times per PV) using a circular mapping catheter for an observation period of 87 ± 29 minutes. After isolation of all 4 PVs, 30 mg of adenosine triphosphate (ATP) was administered during isoproterenol infusion.
Results: PV electrical isolation was initially achieved in all 81 PVs. During the observation period, 12 (15%) PVs in 10 (48%) of 21 patients exhibited spontaneous reconduction. Among the remaining 69 PVs, 8 (12%) additional PVs had reconduction with the use of ATP. All PV reconduction was successfully eliminated by 4.5 ± 2.2 additional radiofrequency applications.
Conclusion: A sufficient observation period and the use of ATP are useful to detect early reconduction after PV isolation.     

疝环充填式无张力疝修补术在老年腹股沟疝中的应用

目的 探讨疝环充填式无张力疝修补术在老年度股沟疝中的应用价值。方法 选择年龄在60岁以上的老年腹股沟疝,共有28例,其中合并其他慢性疾病20例,占71.5％,复发性疝3例,均使用本方法做疝修补术。结果 本组近期随访,效果良好。无复发及严重的术后并发症。结论 疝环充填式疝修补术操作简单,术后复发率低,并发症少,能早期活动,尤其适合于有多种慢性疾病并存的老年腹股沟疝。     

A Case of Rectal Carcinoma in a Part of a Giant Periproctal Abscess

Abstract: A 58-year-old male was admitted to our hospital complaining of perineal pain and weight loss. On digital examination, a hard mass with a central depression was palpable in the circumference of the rectum. A barium enema study revealed a giant periproctal abscess formation, and a colonoscopy showed a giant irregular-shaped ulceration in the circumference of the rectum. Biopsy specimens obtained from the rectal ulcer revealed a well differentiated adenocarcinoma, and this case was diagnosed as being carcinoma of the rectum with periproctal abscess formation. A pelvic exenteration and colostomy were performed. The macroscopic findings of the resected rectal specimen showed a giant abscess formation measuring 13 cm over the anal verge in the circumference of the lower rectum. The abscess, with a thickened wall measuring 50 mm, was accompanied by an ulcerated lesion on its oral and anal side. The tumor was adherent to the bladder and prostate with direct invasion. The post operative diagnosis made was an unclassified type of rectal carcinoma (type 5). Its clinical staging was stage 5 (HIPON1A3) in gross appearance. The histopathological findings of the resected specimen indicated a poorly differentiated adenocarcinoma partly containing signet ring cell carcinoma. The frequency with which a rectal carcinoma with a regional abscess has been reported is less than 1%. It has been assumed that a regional abscess is caused by the perforation of the rectum contributing with the invasion of carcinoma over the proper muscle layer. In this case, it was inferred that the rapid development of this tumor caused secondary, ischemia at its center and then an abscess was formed with tumor necrosis.     

A Case of Early Gallbladder Carcinoma Associated with the Anomalous Union of the Pancreaticobiliary Ductal System

Abstract: A 68 year-old woman was admitted to our hospital with a high fever. Ultrasonography revealed the presence of two protruded mass lesions in the fundus of the gallbladder. Endoscopic retrograde choledochopancreatography (ERCP) indicated an anomalous union of the pancreaticobiliary ductal system (AUPD), with an anomalous junction heated at the site 30 mm proximal to the ampulla of Vater. ERCP also showed the presence of three flat elevated lesions at the fundus of the gallbladder. Amylase activity in the bile obtained from the common bile duct during ERCP was high. From these findings, gallbladder carcinoma associated with AUPD was suspected. Cholecystectomy, choledochectomy followed by hepaticojejunostomy were performed on this patient. A microscopic study of the resected gallbladder demonstrated adenocarcinoma with epithelia like intestinal metaplasia in those elevated lesions surrounded by mucosa associated with atypical hyperplasia without intestinal metaplasia. The authors believe that intestinal metaplasia is the main change accompanied by the cancer, but atypical hyperplasia was an important pre-cancerous lesion in this case.