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101.
We have electrophoretically obtained platelet-derived growth factor (PDGF)-related protein from human glioma (glioma derived PDGF-related protein: GD-PDGF) and produced rabbit antiserum against the monomer of GD-PDGF. By methods of immunoaffinity chromatography and Western blotting, we analyzed GD-PDGF in cultured human glioma cells and conditioned medium. The intracellular GD-PDGF was only detected at 17 kd molecular weight by the purified rabbit antibody. When the intracellular 17 kd monomer was purified by the IgG-coupled immunoaffinity chromatography, the eluted protein was not detected at 17 kd but at 52 kd. The 52 kd GD-PDGF was spontaneously and immediately converted to 56 kd, which was partly degraded to 32 and 35 kd within 24 hours. On the other hand, in the conditioned media of glioma cell lines GD-PDGF presents mainly as 56 kd. The assembled forms of GD-PDGF exhibited a powerful activity to induce membrane ruffle formation and reorganization of actin filaments in cultured glial cells and glioma cells. These results indicated that GD-PDGF is intracellularly stored as 17 kd monomer and exists extracellularly as assembled forms, which may act as an autocrine and paracrine effect on the surrounding cells.  相似文献   
102.
Aims: Regenerating islet‐derived family, member 4 (Reg IV) is associated with the progression of various cancers. The aim was to examine Reg IV expression in adenoid cystic carcinomas (ACCs) in salivary glands. Methods and results: Reg IV expression was detected by immunohistochemistry and compared with clinicopathological parameters. Expression of phosphorylated epidermal growth factor receptor (pEGFR), phosphorylated AKT (pAKT) and MUC2 was examined by immunohistochemistry. Reg IV function was assessed with Reg IV antisense S‐oligodeoxynucleotides (AS) in ACC3 human ACC cells. Reg IV was expressed by salivary duct epithelia and acinus myoepithelia, but not in squamous epithelia. Reg IV expression was found in 41% (17/41) of ACCs, but in none of 40 oral squamous cell carcinomas (OSCCs) and was associated with nodal metastasis (P = 0.047) and poor prognosis (P = 0.012) in ACCs. Reg IV expression was associated with pEGFR (14/17, 82%) in Reg IV + ACCs, but had no relationship with pAKT or MUC2 expression in ACCs. Cell growth was inhibited by AS treatment in Reg IV + ACC3 cells, but not in HSC‐4 OSCC cell s , whereas in vitro invasion of neither cell types was affected by AS treatment. Conclusions: These results suggest that Reg IV might accelerate cell growth and disease progression of ACCs.  相似文献   
103.
To determine the difference between alcoholic hepatitis (AH) and non-alcoholic steatohepatitis (NASH) in Japan, six patients with Ah and four patients with NASH, recently treated at our institute, were clinically and pathologically evaluated. Clinical features of the diseases differed: in NASH patients, mean age was higher, mean body mass index much higher, and the prevalence of diabetes mellitus was higher than in AH patients. The patients with NASH presented with unremarkable symptoms and signs. Abnormalities in liver function tests including prothrombin time and choline esterase were mild in NASH patients, except for the indocyanine green test. They had ALT-dominant hypertransaminasemia. AST, ALT and gamma GTP did not normalize as promptly as in AH patients after admission. However, there was no significant difference in the histological grade of fibrosis, inflammation or hepatocytic metamorphosis between NASH and AH patients. Stellate-form fibrosis was characteristic of AH, whereas pericellular and perivenular types were common in NASH patients. Focal cell necrosis was rather intense, and fatty deposits prominent, in NASH patients. However, it was difficult to histopathologically discriminate between NASH and AH patients. If AH is histologically suspected in non-alcoholic patients, the possibility of NASH should always be considered. Furthermore, even in patients with suspected simple fatty liver, a liver biopsy should be performed, especially in cases with prolonged abnormal liver function findings.  相似文献   
104.
To improve and standardize the measurement of small bowel transit time, milk was employed for the test meal instead of the conventional lactulose meal. Although 92% of the subjects were lactase deficient, only 2% were milk intolerant and 13% were lactose intolerant. Small bowel transit time with milk (milk breath hydrogen test) was 113±9 min (mean ± SE,n=20); the normal range calculated from the mean ±2 SD was 31–195 min. The coefficient of variation in the milk hydrogen breath test was 13 ± 4% (n=6), whereas in the lactulose hydrogen breath test, it was 39±16% (n=10). The frequency of non-hydrogen producers, the occurrence of discomfort, and the reproducibility were better, though not significantly so, in the milk hydrogen breath test than in the lactulose. Since lactase activity in the intestine is variable in lactase-deficient subjects, small bowel transit times for milk may change from subject to subject. However, individual reproducibility of the milk hydrogen breath test is good. It could be useful for pharmacological experiments using paired comparison, for screening tests, or for the follow up of diseases in which small bowel transit time is affected.  相似文献   
105.
Background: The severe types of central serous chorioretinopathy (CSC) have a chronic nature, suggesting that a pathological process persists subclinically. Indocyanine green(ICG) angiography recently revealed intrachoroidal dye leakage and its static nature in CSC. As the intrachoroidal dye leakage was suspected to be relevant to the disease process, the long-term persistence of intrachoroidal ICG leakage was examined in four patients of the severe types of CSC. Methods: ICG angiography was performed periodically over more than three years in three patients and two years in one patient. One patient had CSC with bullous retinal detachment, and the other three had chronic CSC or diffuse retinal pigment epitheliopathy. Results: Intrachoroidal ICG leakage persisted in all the patients. However, a change in location of persistent intrachoroidal leakage or disappearance of intrachoroidal leakage regardless of no progression of retinal pigment epithelial alteration was noted in one eye of two patients. Conclusions:Pathology causing intrachoroidal ICG leakage persisted subclinically for a long period. However, location and extent of the intrachoroidal leakage could change during along-term follow-up period. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
106.
107.
Despite the semi-routine use of color Doppler sonography for evaluating portal circulation abnormalities, there is a relative paucity of information on portal-systemic (P-S) shunt through the right renal vein (P-SR shunt). We report such a case. The patient was a 60-year-old woman with hepatocellular carcinoma on liver cirrhosis. Serial sonography showed an aggravation in findings; an increase in the size of the tumor was followed by formation of a portal tumor thrombus, and then occurrence of a P-SR shunt. We present this case, with a comparison between the patient's clinical course and the color Doppler results. To our knowledge, this is the first report to make such a comparison in a P-SR shunt case. We also briefly review the literature.  相似文献   
108.
109.

Background:

Bilateral Wilms tumours (BWTs) occur by germline mutation of various predisposing genes; one of which is WT1 whose abnormality was reported in 17–38% of BWTs in Caucasians, whereas no such studies have been conducted in East-Asians. Carriers with WT1 mutations are increasing because of improved survival.

Methods:

Statuses of WT1 and IGF2 were examined in 45 BWTs from 31 patients with WT1 sequencing and SNP array-based genomic analyses. The penetrance rates were estimated in WT1-mutant familial Wilms tumours collected from the present and previous studies.

Results:

We detected WT1 abnormalities in 25 (81%) of 31 patients and two families, which were included in the penetrance rate analysis of familial Wilms tumour. Of 35 BWTs from the 25 patients, 31 had small homozygous WT1 mutations and uniparental disomy of IGF2, while 4 had large 11p13 deletions with the retention of 11p heterozygosity. The penetrance rate was 100% if children inherited small WT1 mutations from their fathers, and 67% if inherited the mutations from their mothers, or inherited or had de novo 11p13 deletions irrespective of parental origin (P=0.057).

Conclusions:

The high incidence of WT1 abnormalities in Japanese BWTs sharply contrasts with the lower incidence in Caucasian counterparts, and the penetrance rates should be clarified for genetic counselling of survivors with WT1 mutations.  相似文献   
110.
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   
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