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61.
The recovery of all of the islets contained in a pancreas is the goal of islet isolation for transplantation. This study reveals an environment that injures the isolated islets during digestion and proposes a new model for optimal islet isolation. Islets were isolated from Wistar rat pancreases by stationary collagenase digestion while the digestion time was varied at 15, 30, 60, and 120 min. The digested pancreas and islets were analyzed histologically and adenosine nucleotides were measured. Overnight cultured islets (40 islets) were cocultured for 30 min with the supernatants obtained from pancreatic collagenase digestion at different digestion periods in order to assess the toxic environment. The peak yields of islets were obtained at 30 min of digestion. The histological study of digested pancreas showed that the exocrine cells lost their cellular integrity at 120 min of digestion, but the islet cells were left intact. Accordingly, the ATP levels of the pancreatic tissue decreased during the digestion period. The coculture experiment demonstrated that the islets cultured with the supernatants from the collagenase digestion showed digestion time-dependent disruption of the cellular integrity of islets in accordance with a rapid decrease of ATP levels in the islets. The addition of serine protease inhibitors into this coculture clearly showed protection of islets, which maintained high ATP levels in association with intact membrane integrity as assessed by AO/PI staining. Morphological deterioration of islets as well as a marked ATP decrease was evident in the entire digested pancreas as well as in islets cocultured in the supernatants from the collagenase digestion. Various factors toxic to the islets can therefore be analyzed in future experiments using this coculture model for obtaining a good yield of viable islets.  相似文献   
62.
Obata H  Li X  Eisenach JC 《Anesthesiology》2005,102(3):657-662
BACKGROUND: Spinally administered clonidine produces analgesia via alpha2-adrenergic receptors. The analgesic potency of clonidine and its dependency on muscarinic acetylcholine receptors increase in rats after nerve injury. The authors hypothesized that these changes reflect greater acetylcholine release from the spinal cord by clonidine, either through direct or indirect effects. METHODS: Male Sprague-Dawley rats were divided into two groups: no surgery or left L5 and L6 spinal nerve ligation (SNL). All experiments were performed 3 weeks after SNL. Crude synaptosomes were prepared from the spinal enlargement and loaded with [H]choline. Samples were incubated with clonidine in the absence or presence of KCl depolarization. The authors also examined the effect of clonidine on KCl evoked acetylcholine release using perfusion of spinal cord slices, in which some spinal circuitry is maintained. RESULTS: In synaptosomes, clonidine alone induced minimal acetylcholine release, which was actually greater in tissue from normal rats than in tissue from SNL rats. In the presence of KCl depolarization, however, clonidine enhanced acetylcholine release in tissue from SNL rats but inhibited release in tissue from normal rats. Similarly, in spinal cord slices, clonidine enhanced KCl evoked acetylcholine release in tissue from SNL animals but inhibited such release in tissue from normal animals. The alpha2-adrenoceptor antagonist idazoxan inhibited the effects of clonidine in slices from SNL rats. CONCLUSION: These results suggest that clonidine enhances depolarization-induced acetylcholine release in neuropathic but not in normal spinal cord tissue. Interestingly, this enhanced acetylcholine release by clonidine occurs in a synaptosomal preparation, consistent with a direct effect on alpha2 adrenoceptors on cholinergic terminals. Enhanced release of acetylcholine by clonidine could contribute to increased analgesia of clonidine in neuropathic pain.  相似文献   
63.
A 66-year-old male patient has been on continuous ambulatory peritoneal dialysis (CAPD) since 1993, and was diagnosed with right hydrocele of the spermatic cord in 1998. He repeatedly developed CAPD-related bacterial peritonitis 3 times. In February 2001, hemodialysis was prescribed for treatment of mycotic peritonitis. A palpable mass was noted in the right inguinal region in October 2001 and a computed tomographic (CT) scan disclosed a 4 cm circular lesion with relatively low density and thick wall in the right inguinal region. Spermatic-orchiectomy was performed. Histological diagnosis was mycosis like Candida on the abscess wall. To our knowledge, this is the first case of spermatic cord abscess in a CAPD patient in the Japanese literature.  相似文献   
64.
65.
A 46-year-old woman presented with a hypogastric mass. The preoperative diagnosis was a malignant ovarian tumor involving multiple organs, including the urinary bladder. Surgical exploration was performed with wide resection of the right ovary and uterus, including the affected ileum, sigmoid colon, and omentum. An intraoperative histopathological examination of the paravesical tissue revealed abdominal actinomycosis. Consequently, bladder resection was not done. The cause of abdominal actinomycosis in this patient was probably due to implantation of an intrauterine device 3 years previously.  相似文献   
66.
T cells mediating chronic rejection (CR) of human kidney allografts were characterized by comparing them with those mediating acute rejection (AR). Two lines of analysis were performed using biopsy specimens (23 CR and 8 AR). First, the extent of infiltration of CD4+ and CD8+ T cells into allografts was assessed from mRNA expression of CD4 and CD8. The group of CR specimens was not significantly different from the group of AR specimens in terms of the extent of CD4+ and CD8+ T cell infiltration, underlining the importance of the immunological contribution to the progress of CR. Second, Th1/Th2 polarization in infiltrating T cells was investigated by measuring mRNA expression of interferon gamma (IFN-gamma; a Th1 cytokine) and interleukin 4 (IL-4; a Th2 cytokine). IFN-gamma expression was detected in most CR specimens, and was not significantly different between the group of CR specimens and the group of AR specimens. On the other hand, IL-4 expression was detected in only two CR specimens and one AR specimen; from its pathological features, the AR in this last case was concomitant with CR. These results suggest that most cases of CR and of AR are mediated by Th1 mechanisms, although some cases of CR show features of both Th1 and Th2.  相似文献   
67.
OBJECTIVE: We placed temporary inferior vena cava filters to prevent pulmonary thromboembolism in patients with deep vein thrombosis (DVT) who were presumed to have an increased risk of pulmonary embolism in the perinatal period. These experiences of using temporary inferior vena cava filters in pregnant women are reported. METHODS: We reviewed 11 patients with DVT who underwent placement of a temporary inferior vena cava filter and delivered in our hospital between 1998 and 2004. All of the filters were placed at the suprarenal inferior vena cava before delivery. During filter placement, anticoagulant therapy was routinely performed, and we stopped the administration of anticoagulant agents intrapartum. RESULTS: No complications occurred at filter insertion or during placement. No symptomatic pulmonary thromboembolism occurred during or after delivery. All of the filters were successfully removed, one of which was exchanged for a permanent filter because the temporary filter captured a large thrombus. CONCLUSION: Intrapartum temporary inferior vena cava filters may reduce the incidence of pulmonary thromboembolism in pregnancy with DVT. Temporary inferior vena cava filters appear to be safe for pregnant women.  相似文献   
68.
During bowling, a twenty year old man could not pull out his middle finger from the ball in release and injured his finger. X-ray revealed a palmar fracture- dislocation of the PIP joint. We manipulated the PIP joint, but a gap remained at the fracture site on the X-ray after reduction. Surgical treatment was performed with a screw. Postoperatively, the middle finger was fixed with a splint for two weeks, and then active range of motion exercises were started. One year after the operation, the fracture had healed with a congruous joint surface, and the patient had full range of motion in the middle finger with no difficulties in activities of daily living. The etiology of a palmar fracture-dislocation of the PIP joint is still controversial, but we suggested the mechanism of the fracture-dislocation was caused by a shearing force to the middle phalangeal base from a dorsal direction. The main cause of the current injury was the poor fit between the middle finger and the hole of the bowling ball. Bowling is a popular and safe sport, but we should be aware of unexpected hand injuries related to bowling which may occur, especially in players at a recreational level.

Key points

  • We presented a palmar fracture-dislocation of the PIP joint in a middle finger that occured while bowling.
  • We discussed the mechanism and suggested the main cause of the injury was the poor fit between the middle finger and the hole of the bowling ball.
  • We advised that while bowling is recognized as a safe sport, due to its popularity we should be aware of unexpected hand injuries which may occur, especially in players at a recreational level.
Key words: Palmal fracture-dislocation, PIP joint, bowling, sports  相似文献   
69.
Background: Spinally administered clonidine produces analgesia via [alpha]2-adrenergic receptors. The analgesic potency of clonidine and its dependency on muscarinic acetylcholine receptors increase in rats after nerve injury. The authors hypothesized that these changes reflect greater acetylcholine release from the spinal cord by clonidine, either through direct or indirect effects.

Methods: Male Sprague-Dawley rats were divided into two groups: no surgery or left L5 and L6 spinal nerve ligation (SNL). All experiments were performed 3 weeks after SNL. Crude synaptosomes were prepared from the spinal enlargement and loaded with [3H]choline. Samples were incubated with clonidine in the absence or presence of KCl depolarization. The authors also examined the effect of clonidine on KCl evoked acetylcholine release using perfusion of spinal cord slices, in which some spinal circuitry is maintained.

Results: In synaptosomes, clonidine alone induced minimal acetylcholine release, which was actually greater in tissue from normal rats than in tissue from SNL rats. In the presence of KCl depolarization, however, clonidine enhanced acetylcholine release in tissue from SNL rats but inhibited release in tissue from normal rats. Similarly, in spinal cord slices, clonidine enhanced KCl evoked acetylcholine release in tissue from SNL animals but inhibited such release in tissue from normal animals. The [alpha]2-adrenoceptor antagonist idazoxan inhibited the effects of clonidine in slices from SNL rats.  相似文献   

70.
PURPOSE: To evaluate the efficacy of hand-assisted laparoscopic radical nephrectomy (HALRN) in patients with localized stage T(1)/T(2) renal-cell carcinoma, we analyzed the clinical results of our patients treated in this way. PATIENTS AND METHODS: From March 1999 to March 2003, a total of 96 patients aged 28 to 86 years (mean 61 years) with clinical stage T(1)/T(2)N(0)M(0), pathologically confirmed renal-cell carcinoma underwent HALRN. The outcomes were compared with those of open radical nephrectomy, which was performed in 86 patients from November 1991 to February 1999 in our institution. Kaplan-Meier analysis was used to analyze survival. RESULTS: Ten patients (10.4%) had perioperative complications. During a mean follow-up of 25 months (range 6-54 months), no patients died of the cancer, although three patients had metastatic disease. The 4-year disease- free and overall survival rates were 88% and 100%, respectively. Seventy-eight patients who underwent open radical nephrectomy were followed for 38 to 156 months (median 86 months). Seventy-three survived without any recurrent disease, five survived with metastasis, and no patient died of metastatic disease. The 4-year disease-free and overall survival rates were 93% and 100%, respectively. CONCLUSIONS: Hand-assisted laparoscopic surgical management of T(1)/T(2) renal-cell carcinoma is feasible and safe. At our institution, HALRN confers long-term oncologic effectiveness equivalent to that of open radical nephrectomy.  相似文献   
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