Biomedical subjects

Y Yamamura

Publications and source records attributed to Y Yamamura.

At least 127 records · Page 7Linked to original sources

PubMed1997

The pharmacokinetics of glycyrrhizin and its restorative effect on hepatic function in patients with chronic hepatitis and in chronically carbon-tetrachloride-intoxicated rats.

The relationships between the pharmacokinetic behaviour of glycyrrhizin and its restorative effect for hepatic function were investigated in patients with chronic hepatitis and in rats chronically treated with carbon tetrachloride (CCl4-treated rats). In patients, the restorative effects in plasma aspartate aminotransferase (AST) and alanine aminotransferase (ALT) activities were 62.2 +/- 7.4 and 64.4 +/- 7.5%, respectively, after daily 80 mg intravenous (i.v.) doses of glycyrrhizin for 2 weeks, and 63.1 +/- 19.1 and 68.7 +/- 15.2% after 120 mg doses. The present work suggests that the threshold plasma glycyrrhizin concentration for sufficient effect is near 5 micrograms mL-1. In rats, the total body clearance (Cltot) for glycrrhizin in the CCl4-treated rats after i.v. administration of glycyrrhizin (5 mg kg-1 dose) was three-tenths of that of the control, and the t1/2 for glycyrrhizin was 3.4-fold longer than that of the control. A good correlation was observed between Cltot and AST (r = -0.838) or ALT (r = -0.873) activity in both rats. When glycyrrhizin was administered intraperitoneally (i.p.) three times a week for 2 weeks, both the AST and ALT activities in the CCl4-treated rats showed a greater improvement than for a 10 mg kg-1 dose. Furthermore, the finding on the threshold plasma concentration in patients as above was also supported from the results of the experiments in rats.

Alanine Transaminase↗

PubMed1997

Gastric cancer with carcinoma erysipeloides caused by spontaneous thoracic duct rupture: report of a case.

A case of extensive skin metastasis (carcinoma erysipeloides) resulting from spontaneous rupture of the metastasized Virchow lymph node in a 53-year-old woman is herein reported. Imaging evidence attributing this metastasis to spontaneous rupture of the fragile thoracic duct at the supraclavicular fossa is presented. The patient, who had already undergone gastric resection more than 6 years previously because of advanced gastric cancer, died approximately 4.5 months after the occurrence of lymphorrhea in her neck since the anticancer chemotherapy administered demonstrated little or no effect.

Carcinoma↗

PubMed1997

Intestinalization of gastric signet ring cell carcinomas with progression.

Recent developments in mucin histochemistry and immunohistochemistry have made reliable determination of the gastric and intestinal phenotypes of gastric carcinoma cells possible. Phenotypic expression changes from gastric epithelial cell type to intestinal epithelial cell type with the growth of gastric tumours in experimental animals. We studied cell differentiation in gastric signet ring cell carcinomas with progression in 203 surgically obtained specimens. The results showed that the proportion of gastric phenotype carcinomas, in which over 90% of the tissue consists of gastric epithelial cell type cells, decreases with the depth of invasion. The proportion of mixed phenotype carcinomas (between 10% and 90% of the tissue made up of gastric and/or intestinal epithelial cell type cells) increases. The intestinal phenotype (over 90% intestinal epithelial cell type carcinoma cells) was found in four carcinomas (about 2%) involving the serosa. No clear relationship was evident between phenotypic expression of carcinoma cells and the degree of intestinal metaplasia of the surrounding mucosa. Progression of gastric signet ring cell carcinomas is associated with a phenotypic shift from gastric to intestinal type expression.

Carcinoma, Signet Ring Cell↗

PubMed1997

Metastatic gastric lymph node rate is a significant prognostic factor for resectable stage IV stomach cancer.

BACKGROUND: Stage IV gastric carcinoma is rarely curatively resected and almost invariably carries a poor prognosis. Several clinicopathologic factors are involved, but lymphatic spread of the cancer may significantly affect survival. STUDY DESIGN: A retrospective study was designed to evaluate whether the nodal metastatic rate (number of lymph node metastases/number of resected lymph nodes) is a parameter of lymphatic spread and could provide a significant prognostic factor. Several prognostic factors were assessed by multivariate analysis in 153 stage IV gastric carcinoma patients with histopathologic data on nodal metastasis. RESULTS: A significant difference in survival was observed in the stage IV cancer patients with total nodal or gastric nodal metastatic rates < 50% versus those with rates > 50%. Multivariate analysis revealed that a total nodal or gastric nodal metastatic rate > 50% was a highly significant prognostic factor. The gastric nodal metastatic rate can be used in patients who do not undergo an extended lymphadenectomy. CONCLUSIONS: Lymphatic spread of gastric carcinoma expressed in terms of the total nodal or gastric nodal metastatic rate is a significant prognostic factor. The latter can be calculated without pathologic data derived from extended lymphadenectomy, and so it is universally applicable.

Humans↗

PubMed1997

An unusual case of laryngeal carcinoma metastasizing to the small intestine.

An unusual case of laryngeal carcinoma metastasizing to the small intestine is reported. The patient was admitted to our hospital due to hoarseness, sore throat and dyspnoea. Pathological examination on the laryngeal mass revealed it to be moderately differentiated squamous cell carcinoma, staged as T4N0M0. A total laryngectomy and right modified neck dissection were performed. Over two years after the operation a small intestinal tumour was found, with a resultant resection of the ileum and sigmoid colon. An infiltration of the cell nests of squamous cell carcinoma were present at the submucosal regions of the ileum. These findings indicated that the laryngeal cancer had already metastasized to the small intestine at the time of the initial treatment.

Aged↗

PubMed1997

Taxuspinananes A and B, new taxoids from Taxus cuspidata var. nana.

New taxoids, taxuspinanane A (1), showing potent cytotoxic activity, and taxuspinanane B (2), have been isolated from the stems of Taxus cuspidata Sieb. et. Zucc. var. nana Rehder. Their structures were elucidated by extensive 2D NMR and MS spectroscopic analysis.

Animals↗

PubMed1997

A new macroscopic classification predicts prognosis for patient with liver metastases from colorectal cancer.

OBJECTIVE: The authors defined a new macroscopic classification of liver metastases from colorectal cancer. SUMMARY BACKGROUND DATA: There were different prognostic results after the same operative procedure for liver metastases with similar background factors. METHODS: Eighty-one resected liver metastases were classified into simple nodular (SN) or confluent nodular (CN) types according to the characteristics of the cut surface of the tumor. RESULTS: The 5-year survival rates after hepatectomy were 41.7% for the SN lesions (n = 39) and 23.1% for the CN lesions (n = 42). The difference between the survival curves was statistically significant (p = 0.0307). Multivariate analysis using Cox's proportional hazards model revealed that the macroscopic type (p = 0.023), the tumor diameter (p = 0.0001), and the presence of lymph node metastases (p = 0.0016) were statistically significant independent prognostic factors. CONCLUSION: The new macroscopic classification may be valuable as a prognostic factor reflecting the biologic behavior of liver metastases.

Colorectal Neoplasms↗

PubMed1997

Detection of carcinoembryonic antigen-expressing free tumor cells in peritoneal washes from patients with gastric carcinoma by polymerase chain reaction.

Cytological examination of peritoneal washes is a useful predictor of peritoneal recurrence in gastric carcinoma patients. In the present study, even more sensitive detection of free cancer cells could be achieved through amplification of carcinoembryonic antigen (CEA) mRNA by means of the reverse transcriptase-polymerase chain reaction (RT-PCR). CEA was first confirmed to be present in all the gastric cancer cell lines examined, irrespective of the differentiation degree, and absent in blood and mesothelium, indicating the specificity of this approach for detection of carcinoma cells in peritoneal lavage fluid. In sensitivity tests, CEA RT-PCR proved to be capable of detecting 10 carcinoma cells per sample. Peritoneal washes of 15 of 48 gastric carcinoma patients, including all 10 patients with positive cytology results, proved positive for CEA mRNA. None of the 5 patients with benign disease was positive. Moreover, a close association with the depth of cancer invasion was established. The results indicate that the assay is more sensitive for detection of free carcinoma cells in the peritoneal cavity than conventional cytology. This is the first study to suggest the feasibility of the RT-PCR method for prediction of peritoneal recurrence in gastric cancer patients.

Adult↗

PubMed1997

Surgical treatment of early cancer of the proximal third of the stomach.

A retrospective study was conducted in search of an optimal surgical procedure for early cancer of the proximal stomach. The clinicopathological findings and survival data of 128 patients operated on during a recent period of 16 years were analyzed. Nodal metastasis was found in 12% of the patients and had a significant influence on the survival. It was more frequently observed in the undifferentiated type, regardless of the tumor size. Most metastases were found in the proximal paragastric nodes, and no metastasis was observed in the pyloric region or at the splenic hilum. These facts suggest that while the resection of paragastric nodes is advocated, neither total gastrectomy nor splenectomy is required simply for the purpose of lymphadenectomy.

Humans↗

PubMed1997

The 72nd codon change of p53 in primary renal cell carcinoma was confirmed as a polymorphism among Japanese.

OBJECTIVE: The role of p53 mutation in renal cell carcinoma (RCC) is not fully understood particularly among Japanese, although frequent loss of heterozygosity (LOH) has been demonstrated at polymorphic exon 4. METHODS: We examined the p53 gene in 43 primary RCC samples by polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) analysis for exons 4-9 and restriction fragment length polymorphism (RFLP) analysis. RESULTS: In PCR-SSCP analysis, no apparent mobility shift was observed regardless of the clinical stage of the disease, histological subtype or malignancy grade of the tumor. In RFLP analysis, none of 13 informative cases showed gross alteration of the gene. CONCLUSION: We conclude that mutations of the p53 gene are not major events in the development and progression of RCC among Japanese.

Adult↗

PubMed1997

Characteristics of diabetes, blood pressure, and cardiac and renal complications in Otsuka Long-Evans Tokushima Fatty rats.

To characterize the molecular mechanism of cardiac and renal complications in non-insulin-dependent diabetes mellitus (NIDDM), we examined the gene expression of Otsuka Long-Evans Tokushima Fatty (OLETF) rats, a new animal model for human NIDDM, at the ages of 14 weeks (prediabetic stage), 30 weeks (NIDDM stage), and 54 weeks (IDDM stage). Tissue mRNA levels were measured by Northern blot analysis. In 14-week-old OLETF rats, cardiac mRNAs for transforming growth factor-beta1 (TGF-beta1) and extracellular matrix, including collagen types I, III, and IV and laminin, were significantly increased compared with control rats (Long-Evans Tokushima Otsuka rats). Cardiac beta-myosin heavy chain (MHC) mRNA of OLETF was increased at 30 and 54 weeks of age, whereas alpha-MHC mRNA of OLETF was inversely decreased at 54 weeks. Marked perivascular fibrosis was seen in the hearts of OLETF rats from 30 weeks of age. In the kidney of OLETF rats, glomerular TGF-beta1 expression was temporally increased at 30 weeks of age, followed by glomerulosclerosis characterized by mesangial proliferation, thickening of the basement membrane, and nodular lesions. Blood pressure of OLETF rats remained higher than that of control rats from the prediabetic stage to the IDDM stage. Thus, in OLETF rats, cardiac fibrosis-related gene expressions were already enhanced at the prediabetic stage, which supports the involvement of these gene expressions in cardiac perivascular fibrosis. The antithetical change in beta- and alpha-MHC expressions seems to participate in the decreased cardiac contractility seen in diabetes. Furthermore, TGF-beta1 may also contribute to glomerulosclerosis of OLETF rats. OLETF rats seem to be a useful model to study the mechanism of hypertension and cardiac and renal complications in NIDDM.

Animals↗

PubMed1997

Rett syndrome: an analysis using Sartwell's incubation period model.

Evidence suggests that Rett syndrome is a genetic disorder; however, an etiologic genetic model has yet to be identified. The purpose of this study was to apply a statistical model, Sartwell's incubation period model, to estimate the incubation period of Rett syndrome and postulate further on the etiology of Rett syndrome. Sartwell's model was used to test the hypothesis that the age of onset of developmental regression distributions approximate a logarithmic normal model and thus the etiologic factors of Rett syndrome occur in utero or prior to conception. Data from three case-series of Rett syndrome from different geographic regions were used for the analyses. Curves resulting from the analyses demonstrated a good approximation to the logarithmic normal distribution, indicating a good fit of the data to Sartwell's model. In conclusion, the incubation period of Rett syndrome fits the logarithmic normal model, which is consistent with the theory that a major causal factor for Rett syndrome most likely occurs in utero or prior to conception, eg, a defective gene.

Age of Onset↗

PubMed1997

Acute mercury poisoning by intentional ingestion of mercuric chloride.

A 26-year-old woman ingested 0.9 g of mercuric chloride in a suicide attempt and developed hematemesis, melena and acute renal failure. Anuria persisted for 14 days. She was treated by plasma exchange, hemodialysis and peritoneal dialysis in combination with continued dimercaprol chelation. While hemodialysis was ineffective in removing the mercury, plasma exchange effectively eliminated mercury. After two plasma exchange therapies, mercury concentration in the blood decreased linearly on a log scale with half-lives of 23.1 days for whole blood and 19.1 days for plasma, using first-order kinetics. One month after ingestion, renal function recovered to normal as judged by serum creatine and blood urea nitrogen levels, although the beta 2-microglobulin level in urine was still elevated. At a follow-up examination four months later, renal function was found to be completely normal. This indicates that the renal damage caused by acute mercuric chloride poisoning may not be permanent.

Adult↗

PubMed1997

Localization of a gene for an autosomal recessive form of juvenile Parkinsonism to chromosome 6q25.2-27.

An autosomal recessive form of juvenile Parkinsonism (AR-JP) (MIM 600116) is a levodopa-responsive Parkinsonism whose pathological finding is a highly selective degeneration of dopaminergic neurons in the zona compacta of the substantia nigra. By linkage analysis of diallelic polymorphism of the Mn-superoxide dismutase gene (SOD2), we found a family with AR-JP showing perfect segregation of the disease with the SOD2 locus. By extending the linkage analysis to 13 families with AR-JP, we discovered strong evidence for the localization of the AR-JP gene at chromosome 6q25.2-27, including the SOD2 locus, with the maximal cumulative pairwise LOD scores of 7.26 and 7.71 at D6S305 (theta = .03) and D6S253 (theta = .02), respectively. Observation of obligate recombination events, as well as multipoint linkage analysis, placed the AR-JP gene in a 17-cM interval between D6S437 and D6S264. Delineation of the AR-JP gene will be an important step toward our understanding of the molecular mechanism underlying selective degeneration of the nigral neurons.

Adolescent↗

PubMed1997

Plasma concentration of matrix metalloproteinase 9 in gastric cancer.

BACKGROUND: The clinical significance of plasma concentration of matrix metalloproteinase 9 (MMP-9) was investigated in patients with gastric cancer. METHODS: Plasma was obtained from 138 healthy individuals and 70 patients who underwent gastrectomy for gastric cancer at Aichi Cancer Centre between August 1994 and July 1995. Plasma concentrations of MMP-9 were measured using a one-step sandwich enzyme immunoassay employing monoclonal antibodies. RESULTS: Patients with gastric cancer had plasma higher concentrations of MMP-9 than normal subjects. Postoperative concentrations of MMP-9 were lower than preoperative levels. In addition to patients with advanced cancer, those with early gastric cancer also exhibited higher mean values of and positivity rates for MMP-9 than healthy individuals. Preoperative plasma MMP-9 concentration correlated closely with Union Internacional Contra la Cancrum tumour node metastasis (pTNM) stage, severity of T, N and M classification, and tumour size. CONCLUSION: Plasma MMP-9 concentration can be used for detection of primary or recurrent gastric cancer, and for estimation of tumour extent.

Adult↗

PubMed1997

[Myelogenous leukemia in children. ANLL9205 study by Children's Cancer and Leukemia Study Group (CCLSG)].

Treatment results were evaluated in 45 children with acute myeloblastic leukemia (AML) treated on the ANLL-9205 protocol of the Children's Cancer Leukemia Study Group (CCLSG, Japan). In this protocol, terarubicin (THP-ADR), vincristine and continuous infusion of cytosine arabinoside (Ara C) were applied for remission induction therapy (AVC), and VP16+ high dose Ara C were used sequentially for 32 or 48 weeks. Eleven patients received stem cell transplantation. Thirty-eight out of the 43 eligible patients (88.4%) achieved complete remission, and the overall 3-year event-free survival (EFS) was 55.6% (S.E.,10%). This favorable response was attributed mainly to the high induction rate of patients with the M5, M7 FAB subtypes and higher WBC counts (> or = 10 x 10(9)/L). There was no difference in the 3-year EFS of these patients who discontinued treatment between 32 weeks and 48 weeks. Serious toxicities were not observed in this study. These findings suggest that the ANLL-9205 protocol is an effective and safe treatment regimen for childhood AML. When comparing the treatment period of 32 or 48 weeks, the difference was not statistically significant.

Antineoplastic Combined Chemotherapy Protocols↗

PubMed1997

Activation of the JAK1-STAT5 pathway by binding of the Friend virus gp55 glycoprotein to the erythropoietin receptor.

Friend spleen focus forming-virus (F-SFFV) induces acute erythroleukemia in susceptible mice. Initiation of the erythroleukemia is due to binding of the env-related glycoprotein gp55 encoded by F-SFFV to the erythropoietin receptor (EPOR). The gp55/EPOR interaction induces prolonged and growth factor independent proliferation in a factor-dependent cell line. In erythropoietin (EPO) signaling, the JAK2/STAT5 pathway was shown to be activated downstream of the EPOR to transmit the signal to the cells. To determine members of the JAK family and the STAT transcription factor family involved in the gp55/EPOR signaling, we examined tyrosine phosphorylation of JAKs and STATs in F-SFFV-infected erythroid or erythroleukemic cells. JAK1 and STAT5 were constitutively tyrosine-phosphorylated but the DNA binding activity of STAT5 was not induced without EPO stimulation in erythroblastoid cells from spleens of F-SFFV-infected mice and erythroleukemia cell lines derived from gp55-transgenic mice. These results indicate that JAK1 is involved in the gp55/EPOR signaling but STAT5 is not playing an essential role in the growth of those erythroid cells.

Animals↗

PubMed1997

Extraction of substructures of proteins essential to their biological functions by a data mining technique.

Correlation between the sequential, structural, and functional features of proteins is one of the most important open questions in the field of molecular biology. To this problem, we apply a technique known as data mining for discovering associations across protein sequence, structure, and function. We were able to find various association rules on the substructures essential to some protein functions. Moreover, structure-structure associations were found between proteins having different functions. The results suggest that data mining might be a powerful tool in protein analysis.

Algorithms↗