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Biomedical subjects

T Matsubara

Publications and source records attributed to T Matsubara.

At least 127 records · Page 7Linked to original sources

Selection of ganglioside GM1-binding peptides by using a phage library.

Ganglioside Gal beta1 --> 3GalNAc beta1 --> 4(NeuAc alpha2 --> 3) Gal beta1 --> 4Glc beta1 -->1'Cer (GM1)-binding peptides were obtained from a phage-displayed pentadecapeptide library by an affinity selection. The selection processes were in situ-monitored by a quartz-crystal microbalance method, on which a ganglioside GM1 monolayer was transferred. After five rounds of biopanning, the DNA sequencing of 18 selected phages showed that only three individual clones were selected. The peptide sequences of the random region were found to be DFRRLPGAFWQLRQP, GWWYKGRARPVSAVA and VWRLLAPPFSNRLLP. Binding constants of these phage clones to the GM1 monolayer were 10(10) M(-1). Three synthetic pentadecapeptides inhibited the binding of cholera toxin B subunit to the GM1 monolayer with an IC50 of 24, 13 and 1.0 microM, respectively. These peptides will be useful for searching functional roles of ganglioside GMI.

Amino Acid Sequence↗

The effect of dehydroepiandrosterone sulfate administration to patients with multi-infarct dementia.

We measured cerebrospinal fluid (CSF) levels of dehydroepiandrosterone sulfate (DHEAS) by radioimmunoassay in seven patients with multi-infarct dementia (MID), fourteen age- and gender-matched non-demented patients with a history of cerebral infarction and fifteen age- and gender-matched patients without neurological disorders. The levels of DHEAS in CSF of patients with MID were significantly lower than those in non-demented patients with a history of cerebral infarction or those in patients without neurological disorders. Daily intravenous administration of 200 mg DHEAS for 4 weeks markedly increased serum and CSF levels of DHEAS in seven MID patients, improved decrease of daily activities and emotional disturbances in three patients and EEG abnormalities in two patients. The DHEAS therapy may provide a beneficial effect on MID patients.

Activities of Daily Living↗

Idiopathic polypoidal choroidal vasculopathy in Japanese patients.

OBJECTIVE: To describe the vascular nature and clinical features of idiopathic polypoidal choroidal vasculopathy in Japanese patients. METHODS: Patients thought to have idiopathic polypoidal choroidal vasculopathy were examined with binocular ophthalmoscopy, slitlamp biomicroscopy with a contact lens, fluorescein angiography, and indocyanine green angiography. RESULTS: From January 1993 to December 1997, 35 eyes in 32 patients were diagnosed as having idiopathic polypoidal choroidal vasculopathy. Men were predominantly affected (22 patients [69%]). Most patients were unilaterally involved (29 patients [91%]) and elderly, with a mean age of 65.7 years (range, 44-82 years). Ocular manifestations were relatively mild, with serous or hemorrhagic detachments of the retinal pigment epithelium and neurosensory retina in the posterior pole. Most patients had a favorable course, although some experienced recurrence, and a few eyes developed disciform scarring. In all patients, indocyanine green angiograms demonstrated branching vascular networks with polypoidal dilations at terminals of the network beneath the retinal pigment epithelium. These lesions were mostly in the macula (33 eyes [94%]), with a few in the peripapillary area. CONCLUSIONS: Idiopathic polypoidal choroidal vasculopathy in Japanese patients differs from that in American patients. It seems that this disorder occurs in elderly Japanese patients and should be treated as a distinct clinical entity. It is probably a peculiar form of choroidal neovascularization beneath the retinal pigment epithelium. We propose the term "polypoidal choroidal neovascularization" for this disorder.

Adult↗

Hepatic lymph node involvement in resected cases of liver metastases from colorectal cancer.

PURPOSE: Lymph node metastasis in the hepatoduodenal ligament is known as one of the most significant prognostic factors after liver resection for colorectal metastasis. However, there have been very few articles on the clinical features of node-positive patients and on detailed distribution of positive nodes. Further, there has been no established strategy on how to handle hepatic lymph nodes during liver resection. To address these subjects, a retrospective study was conducted. METHODS: During the period of 1980 through April 1998, 182 hepatic resections were performed for metastatic colorectal carcinoma. Of these, 78 cases had hepatic lymph node sampling during the operation. Distribution of positive nodes, location of liver metastasis, stage of the primary lesion, and outcome after liver resection were analyzed. RESULTS: Nine cases (12 percent) had secondary lymph node metastases in the hepatoduodenal ligament. The incidence was slightly higher (13.5 percent) in the most recent 44 consecutive cases. There was a tendency for liver metastases in the right lobe to metastasize to No. 12b (or node of the foramen of Winslow, lymph nodes along the common bile duct) and liver metastases in the left lobe to metastasize to No. 8a (anterosuperior group of the lymph nodes along the common hepatic artery). Outcome of node-positive patients (n = 9) was extremely poor (P < 0.001) compared with that of node-negative patients (n = 66), and the most common site of recurrence in the node-positive patients was remnant liver and hepatic lymph nodes. Preoperatively, there were no significant predicting factors for positive hepatic lymph nodes. CONCLUSIONS: No. 8a and No. 12b nodes are principal nodes that should be palpated and sampled during liver resection to check the secondary lymphatic spread from liver metastases. Hepatic nodal involvement indicates the progression of disease beyond simple liver metastases and may not be the indication for simple surgical removal. Further study, including hepatoduodenal dissection and systemic adjuvant chemotherapy, may elucidate the survival benefit, if any, of liver resection in node-positive patients.

Case-Control Studies↗

Successful surgical treatment of aortogastric fistula after an esophagectomy and subsequent endovascular graft placement: report of a case.

An aortogastric fistula is a rare but fatal complication after an esophagectomy and intrathoracic esophagogastric anastomosis. A 54-year-old man underwent an esophageal resection due to carcinoma in his lower esophagus. The alimentary tract continuity was restored by intrathoracic esophagogastric anastomosis. Forty-six days later, he suffered a massive hematemesis due to an aortogastric fistula which had formed at the esophagogastric suture line. The fistula was surgically obliterated twice, but each operation was followed by pseudoaneurysm formation. The patient was finally successfully treated with an endovascular stent graft placement. This is the first report of a patient surviving after developing this complication.

Anastomosis, Surgical↗

p53 gene mutations and overexpression of p53 product in cancerous and noncancerous biliary epithelium in patients with pancreaticobiliary maljunction.

To investigate the molecular mechanisms of the high incidence of carcinogenesis in the biliary epithelium of patients with pancreaticobiliary maljunction, we examined p53 gene mutations, loss of heterozygosity of p53, and overexpression of p53 gene product in the cancerous and noncancerous biliary epithelium of 27 patients with pancreaticobiliary maljunction. Mutations of the p53 gene were examined by polymerase chain reaction-single strand conformation polymorphism and a direct sequencing method. Loss of heterozygosity of the p53 gene was determined using a double-targeted fluorescence in situ hybridization method. Expression of p53 gene product was examined using immunohistochemical staining. Mutations of the p53 gene were found in 4 of 5 biliary carcinomas (80%) and in 10 of 26 noncancerous biliary lesions (38.5%). Point mutations of the p53 gene were detected at codons 207, 212, and 217 on exons 5 through 8. The incidence of p53 gene mutations on exons 5, 6, 7, and 8 was 12. 9%, 36.4%, 0.0%, and 13.8%, respectively. Loss of heterozygosity of p53 was shown in 72% of the cells obtained from the cancerous lesion, and in an average of 14% obtained from the noncancerous lesions. Overexpression of p53 protein was found in 57.1% of carcinoma, and in 31.3% of the noncancerous lesions. These results suggest that p53 gene mutations are involved in the carcinogenesis of biliary epithelium in patients with pancreaticobiliary maljunction.

Adult↗

Estrogen effects on platelet-activating factor and platelet-activating factor acetylhydrolase activity in rat uterus during the late stages of pregnancy.

The platelet-activating factor (PAF) concentration of the uterus spontaneously increased during pregnancy. When 17alpha-ethynylestradiol (0.25 mg/kg) was administered subcutaneously to pregnant rats for 3 days starting on Day 17 of pregnancy, some rats delivered prematurely on Day 20. However, none of the vehicle-treated (80% dimethylsulfoxide and 20% ethanol) pregnant rats delivered prematurely. The PAF concentration of the uterus in pregnant rats treated with 17alpha-ethynylestradiol was significantly higher than in those treated with vehicle on Days 19 and 20. On the other hand, the specific activity of uterine PAF-acetylhydrolase (PAF-AH) in pregnant rats treated with 17alpha-ethynylestradiol was significantly lower than in those treated with vehicle on Days 19 and 20, and the plasma PAF-AH activity in pregnant rats treated with estrogen was also significantly lower than in treated with vehicle on Days 18, 19, and 20. These findings indicate that estrogen increases PAF concentrations in the rat uterus, and this was correlated with a decrease in PAF-AH in the uterus and plasma. The increase in PAF concentrations in the uterus may be related to premature delivery and labor caused by PAF's known effect on myometrial contraction.

1-Alkyl-2-acetylglycerophosphocholine Esterase↗

Unique distribution patterns of metastatic lymph nodes in patients with superficial carcinoma of the thoracic oesophagus.

BACKGROUND: Lymph node metastasis is commonly found in carcinoma of the thoracic oesophagus, even when the tumour invades only the submucosa. Although lymph node status greatly influences the outcome, the pattern of early lymphatic spread has not been investigated, and the role of lymph node dissection is still a matter of controversy. METHODS: A series of 110 patients with superficial carcinoma who underwent systematic extended lymph node dissection was investigated retrospectively. RESULTS: Lymph node involvement was found in 0 per cent (none of nine), 23 per cent (five of 22) and 49 per cent (38 of 78) of tumours that invaded the lamina propria, muscularis mucosa and submucosa respectively. Anatomically distant lymph nodes (recurrent nerve nodes and perigastric nodes) were involved more frequently than other intrathoracic nodes adjacent to the main tumour. Only three patients had involvement limited to the intrathoracic group, and in carcinoma that invaded only the muscularis mucosae, all metastatic nodes were located at the thoracocervical junction or in the abdomen. The 5-year survival rate was 89 per cent in the node-negative group and 54 per cent in the node-positive group (P < 0.0003). CONCLUSION: The recurrent nerve nodes and perigastric nodes are the principal proximal regional lymph nodes involved in superficial carcinoma of the thoracic oesophagus. Systematic lymph node dissection, which included these nodes, yielded an acceptable and favourable outcome in patients with node-positive superficial carcinoma.

Carcinoma, Squamous Cell↗

Decreased interferon-gamma (IFN-gamma)-producing T cells in patients with acute Kawasaki disease.

Kawasaki disease (KD) is an acute febrile illness of early childhood, in which the activation of monocytes/macrophages plays a central role in the development of vasculitis during the acute stage of disease. In this study we investigated peripheral blood T cells of 10 patients with KD, focusing on the Th1 and Th2 imbalance, using intracellular cytokine staining and analysis of the cytokine-producing T cells by flow cytometry. We observed a decrease in the numbers of IFN-gamma-producing, but not IL-4-producing, CD3+ T cells, during the acute stage. Our results suggest that there is an imbalance of Th1 and Th2 subsets during the acute stage of KD.

CD3 Complex↗

A high molecular weight glycoprotein in seminal plasma is a sperm immobilizing factor in the teleost Nile tilapia, Oreochromis niloticus.

Sperm that have acquired potential for motility are kept immotile in seminal plasma in the teleost, Nile tilapia. In order to investigate the mechanism of immobilization, several experiments were performed using a previously characterized monoclonal antibody (TAT-30) against a molecular weight (Mr) = 120,000 protein that is secreted by Sertoli cells and epithelial cells of the sperm duct, and is also bound to the head of the spermatozoon. First, we assessed sperm motility in the seminal plasma protein fraction (SPP), and demonstrated that the sperm motility is inhibited by SPP in a concentration-dependent manner. Furthermore, sperm motility was recovered if SPP was pretreated with TAT-30, suggesting that the TAT-30 antigen is one of the components of the sperm immobilizing factor. Calibration by gel filtration followed by sodium dodecylsulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and western blotting with TAT-30 demonstrated that the sperm immobilizing factor was more than Mr = 1,000,000 in seminal plasma, suggesting that it is a homopolymer of the Mr = 120,000-TAT-30 positive protein. Additionally, lectin blot analysis showed that the TAT-30 antigen was reactive with Lens culinarin agglutinin (LCA) and Conavalia ensiformis agglutinin (ConA), indicating that it is a glycoprotein. Immunohistochemical studies showed that the TAT-30 antigen was localized specifically on the heads of spermatozoa and on the apical surface, lysosomes and rough endoplasmic reticulum of Sertoli cells.

Animals↗

Indocyanine green angiography and pathophysiology of multifocal posterior pigment epitheliopathy.

PURPOSE: To clarify the pathophysiology of multifocal posterior pigment epitheliopathy (MPPE), or bullous retinal detachment (RD)-an unusual manifestation of central serous chorioretinopathy (CSC)-we evaluated indocyanine green (ICG) angiographic findings of patients with MPPE. METHODS: Indocyanine green angiography was performed on 45 eyes of 26 patients with MPPE in our clinic during a 4-year period and compared with clinical and fluorescein angiographic (FA) findings. RESULTS: Ophthalmoscopically, in the posterior pole there were multiple yellowish-white retinal exudations, associated with flat, serous RD and bullous RD in the lower periphery. Fluorescein angiography demonstrated multiple massive leakages from the choroid into the subretinal space. These leakage sites corresponded to the retinal exudations. Indocyanine green angiography showed hyperfluorescence in the posterior pole of the choroid. The hyperfluorescence was first seen in the middle phase and became prominent in the late phase. This finding seems to be due to extravasation from the choriocapillaris. After laser photocoagulation of the leakage sites seen on FA, the leakages stopped and the retinal exudations and RD were resolved. Indocyanine green angiography, however, revealed hyperfluorescence in the posterior pole that was seen in active stage. DISCUSSION AND CONCLUSION: These ICG angiographic findings for MPPE show that hyperpermeability of the choroidal vessels may be the primary causative lesion. This is followed by an intrastromal accumulation of the extravasated choroidal fluid, which may be subclinical. Involvement of the retinal pigment epithelium may be secondary, and then the disease becomes manifest with RD. In MPPE, a severe form of CSC, the retinal pigment epithelium is involved extensively and widely, and prognosis is unfavorable. We conclude that MPPE and CSC represent opposite ends of a common morbid spectrum.

Adult↗

Characterization of a newly found stretch-activated KCa,ATP channel in cultured chick ventricular myocytes.

With the use of the patch-clamp technique, five kinds of stretch-activated (SA) ion channels were identified on the basis of their single-channel conductances and ion selectivities in cultured chick ventricular myocytes. Because a high-conductance K+-selective channel predominated among these channels, we concentrated on characterizing its properties mostly using excised inside-out patches. With 145 mM KCl solution in the pipette and the bath, the channel had a conductance of 199.8 +/- 8.2 pS (n = 22). The ion selectivities among K+, Na+, Ca2+, and Cl- as estimated from their permeability ratios were PNa/PK = 0.03, PCa/PK = 0.025, and PCl/PK = 0.026. The probability of the channel being open (Po) increased with the Ca2+ concentration in the bath ([Ca2+]b; dissociation constant Kd = 0.51 microM at +30 mV) and membrane potential (voltage at half-maximal Po = 39.4 mV at 0.35 microM [Ca2+]b). The channel was blocked by gadolinium, tetraethylammonium, and charybdotoxin from the extracellular surface and, consequently, was identified as a Ca2+-activated K+ (KCa) channel type. The channel was also reversibly activated by ATP applied to the intracellular surface (Kd = 0.74 mM at 0.10 microM [Ca2+]b at +30 mV). From these data taken together, we concluded that the channel is a new type of KCa channel that could be designated as an "SA KCa,ATP channel." To our knowledge, this is the first report of KCa channel in heart cells.

Adenine Nucleotides↗

Antihypertensive actions of methylripariochromene A from Orthosiphon aristatus, an Indonesian traditional medicinal plant.

Methylripariochromene A (MRC) was isolated from the leaves of Orthosiphon aristatus (Lamiaceae) and subjected to the examination of several pharmacological actions related to antihypertensive activity. The following four findings were revealed from the present study: 1) MRC caused a continuous decrease in systolic blood pressure and a decrease in heart rate after subcutaneous administration in conscious male SHRSP, 2) MRC exhibited the concentration-dependent suppression of contractions induced by high K+, l-phenylephrine or prostaglandin F2alpha in endothelium-denuded rat thoracic aorta, 3) MRC showed a marked suppression of contractile force without a significant reduction in the beating rate in isolated bilateral guinea pig atria, and 4) MRC increased urinary volume and the excretion of Na+, K+ and Cl- for 3 h after oral administration with a load of saline in fasted rats. These findings indicate that MRC possesses some actions related to a decrease in blood pressure, i.e. vasodilating action, a decrease in cardiac output and diuretic action. Furthermore, it is presumed that the traditional use of this plant in the therapy of hypertension may be partially supported by these actions with MRC.

Animals↗

Perception of dioxin and other risks in Japan: replication and extension.

Previous research has shown that the common understanding of risk may be expressed by factor-analytic models that represent how fatal are risks and how voluntarily one assumes such threats. We investigated whether a similar representation would model Japanese participants' risk perception. Moreover, because Japanese newscasts concentrated their coverage exclusively on dioxin during the period of this research, we expected that those who were exposed to such newscasts would more frequently develop greater environmental awareness. We also examined whether this "news-exposed group's" knowledge about dioxin was consistent with the known facts regarding dioxin. Analysis showed that the two factors adequately modeled the Japanese sample's risk representation (N = 473) and that the news-exposed group (n = 188) did exhibit higher environmental awareness. Implications for risk research are discussed.

Attitude to Health↗

Power Doppler sonography of hepatocellular carcinoma treated by transcatheter arterial chemoembolization. Assessment of the therapeutic effect.

PURPOSE: To evaluate the usefulness of power Doppler sonography (PDS) in assessing the therapeutic effect of transcatheter arterial chemoembolization (TACE) in hepatocellular carcinoma (HCC). MATERIAL AND METHODS: TACE was performed in 43 patients (48 lesions) with HCC. All patients were examined with both PDS and color Doppler sonography (CDS) to assess the therapeutic results 1 week after TACE. Follow-up hepatic angiography was performed in 39 patients 3-4 months after TACE and then CT after iodized oil reinjection was also performed 3-4 weeks after a repeat TACE; in the remaining 4 patients, hepatectomy was performed within one month after chemoembolization and histologic study was undertaken to confirm the Doppler findings. RESULTS: Determination of therapeutic results with PDS and CDS were in agreement with those of follow-up findings in 37 and 29 of the 48 lesions, respectively. There was a significant difference in overall accuracy (p=0.038) between PDS and CDS results. CONCLUSION: PDS is more effective than CDS for evaluating changes in tumor vascularity after TACE. PDS may also replace angiography in assessing the therapeutic effects of TACE for HCCs, except in deep-seated areas.

Aged↗

[Xanthogranulomatous epididymitis. A case report].

A 45-year-old man with spinal injury and diabetes mellitus who complained high fever and progressive enlargement of left intrascrotal mass visited to our hospital. Preoperative ultrasonography demonstrated epididymitis and abscess formation. Left high orchiectomy was performed because testicular tumor could not be denied. Epididymis was replaces by bright yellow mass associated with abscess and adhered to testis strongly. Histopathologically, the mass diagnosed xanthogranulomatous epididymitis consisted of foamy macrophages and chronic inflammatory cells. This is the first case in Japanese medical literature.

Diabetes Complications↗

[Angiographic findings and histological localization of indocyanine green in N-methyl-N-nitrosourea induced retinal degeneration in rats].

PURPOSE: We used N-methyl-N-nitrosourea (MNU) to induce chorioretinopathy as a model of retinitis pigmentosa, and compared the histological localization of indocyanine green (ICG) with ICG angiographic features. METHODS: Brown-Norway pigmented rats received a single intraperitoneal injection of MNU (75 mg/kg body weight). At 3 and 21 days after treatment, we compared ICG angiographic findings with histological localization of ICG in the retina and choroid. Histological localization of ICG was observed with an infrared light microscope. RESULTS: 3 days after treatment, destruction of the photoreceptor cells and photoreceptor segments had developed, and the retinal pigment epithelial cells (RPEs) were also damaged. In ICG angiography, diffuse hyperfluorescence was evident. In histological localization of ICG, RPEs were stained by ICG, and ICG was seen in the sensory retina through the damaged RPEs. At 21 days after treatment, the inner nuclear layer directly contact with the choroid. The photoreceptor cells, RPEs and choriocapillaris had disappeared. In ICG angiography, hypofluorescence was seen in the chorioretinal atrophic area. In histological localization of ICG, there was no ICG in the atrophic area, but ICG leaked from the remaining choriocapillaris into the neighboring sensory retina. CONCLUSION: These results support the precise interpretation of ICG angiographic findings in clinical use.

Animals↗