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S Yamaguchi

Publications and source records attributed to S Yamaguchi.

At least 487 records · Page 27Linked to original sources
PubMed1997

Analysis of proliferative activity of the parathyroid glands using proliferating cell nuclear antigen in patients with hyperparathyroidism.

To elucidate the cellular proliferative kinetics of the parathyroidal gland in patients with hyperparathyroidism, we investigated the expression of proliferating cell nuclear antigen (PCNA) in parathyroidal tissues using an immunohistochemical procedure. The PCNA labeling index (LI; maximum LI, maximal stained area; average LI, evenly distributed stained area) indicating cellular proliferative activity was defined as the number of PCNA-positive cells per 1000 parathyroid cells in the region of interest. We used these indexes to compare and investigate the proliferative activity of parathyroid cells under various conditions. The specimens used for the study were 42 parathyroid glands from 21 patients with primary hyperparathyroidism (19 cases of adenoma and 2 cases of primary hyperplasia due to multiple endocrine neoplasia type 1) and 129 parathyroid glands from 32 patients with secondary hyperparathyroidism. An additional 40 parathyroid glands resected during thyroid surgery of 30 normocalcemic patients were used as normal controls. In normally functioning parathyroids, a small number of cells in the growth phase were found. In primary hyperparathyroidism, proliferative activity was highest in the adenoma followed by primary hyperplasia. In contrast, the PCNA LIs showed a low value in the normal rim of the adenoma and normal glands resected as biopsy specimens from adenoma patients. We, therefore, assumed that proliferative activity was suppressed in these cells compared with that in normally functioning glands. In secondary hyperparathyroidism, when the cell component of the parathyroid tissues was divided into five types, PCNA immunoreactivity was lowest in the dark chief cells. Proliferative activity in cells of the oxyphil series was the same or higher than that in the clear chief cells or vacuolated chief cells. When classified according to the structure of the parathyroid glands, cell proliferation was significantly higher in the nodular type than in the diffuse type (maximum LI, 176 +/- 231 vs. 38.3 +/- 55.7; average LI, 120 +/- 188 vs. 24.8 +/- 43.5; mean +/- SD; P < 0.001). More PCNA-immunoreactive cells were found in autotransplanted glands with recurrence than in glands resected during the initial surgery. To summarize the PCNA expression classified according to the pathological types of hyperparathyroidism, the PCNA LIs were highest in secondary hyperplasia (maximum LI, 144 +/- 212; average LI, 96.0 +/- 169) and adenoma (maximum LI, 102 +/- 81.7; average LI, 67.5 +/- 67.7), followed by primary hyperplasia (maximum LI, 25.0 +/- 25.4; average LI, 19.2 +/- 22.2) and normal glands (maximum LI, 13.6 +/- 23.9; average LI, 4.40 +/- 8.90). These findings suggest that the cellular proliferative kinetics of the parathyroid gland differ depending on the type of hyperparathyroidism, glandular structure, and cell components. As the detection method of intranuclear expression of PCNA in cells is too sensitive, we should be careful not to overestimate the number of cells in the proliferative cycle. However, these results could not have been obtained using a conventional method such as DNA analysis by flow cytometry.

Adenoma↗
PubMed1997

Striatal dopamine metabolism correlated with frontotemporal glucose utilization in Alzheimer's disease: a double-tracer PET study.

We previously found that the rate of [l8F]6-fluoro-L-dopa (FDOPA) uptake into the striatum (the Ki value) in Alzheimer's disease (AD) correlated with cognitive function. Patients with wandering behavior had an increased level of D2 dopamine receptors. Decreased cerebral glucose utilization (CMRglc) in the parietal and temporo-parieto-occipital region is a well-known PET finding in AD. We investigated the relationship between the Ki value and regional CMRglc (rCMRglc) with reference to cognitive impairment and wandering behavior. We studied 10 AD patients with moderately severe dementia. Using PET and the FDOPA and [18F]-fluoro-deoxyglucose techniques, the Ki value and rCMRglc in 10 regions in each hemisphere were measured. The Ki value was found to correlate with mean cortical rCMRglc. The rCMRglc of the anterior frontal, inferior frontal, and temporal lobes correlated with the Ki value; the patients with wandering behavior had lower values. Multiple regression analysis showed that the Mini-Mental State Examination score was significantly explained by the Ki value, the rCMRglc of the temporal lobe, and the rCMRglc of the parietal lobe. There is probably a functional neural network between the striatum and the frontal and temporal lobes in AD. We consider this network important, not only in cognitive impairment but also in abnormal wandering behavior.

Aged↗
PubMed1997

Soluble tumor necrosis factor receptors are elevated in relation to severity of congestive heart failure.

The level of tumor necrosis factor alpha (TNF-alpha) is increased in patients with congestive heart failure and may play an important role in the development and progression of heart failure. Two types of TNF receptor (TNF-RI and TNF-RII) are expressed in virtually every cell and have different biologic roles. Soluble forms of the two receptors (sTNF-RI and sTNF-RII) have been identified as extracellular domain fragments. Serum levels of TNF-alpha, sTNF-RI and sTNF-RII were measured in 66 patients with heart failure and 27 control subjects using an enzyme-linked immunosorbent assay (ELISA). Hemodynamic variables, norepinephrine, atrial natriuretic peptide (ANP), and brain natriuretic peptide (BNP) were evaluated. TNF-alpha was significantly higher in patients with heart failure than in controls subjects (9.4 +/- 1.4 vs 4.8 +/- 0.8 pg/ml; p < 0.05). sTNF-RI and -RII were significantly increased in relation to the severity of heart failure (control subjects, 0.66 +/- 0.04 and 1.97 +/- 0.15 ng/ml; NYHA class II, 1.10 +/- 0.08 and 2.28 +/- 0.12 ng/ml; NYHA class III, 1.63 +/- 0.22 and 3.00 +/- 0.24 ng/ml; NYHA class IV, 2.78 +/- 0.46 and 4.52 +/- 0.62 ng/ml, respectively). In 9 patients whose clinical symptoms improved after treatment, the levels of sTNF-RI and -RII decreased by 17.3 +/- 5.7% (p < 0.05) and 22.1 +/- 6.9% (p < 0.05), respectively. There were significant positive correlations between sTNF-RI and -RII and mean pulmonary pressure (r = 0.69 and r = 0.61; p < 0.001) and mean capillary wedge pressure (r = 0.65 and r = 0.54; p < 0.001 and p < 0.01, respectively), but not with left ventricular end-diastolic volume or ejection fraction (NS). sTNF-RI and -RII were also significantly positively correlated with plasma levels of norepinephrine (r = 0.75 and r = 0.50; p < 0.001 and p < 0.05), ANP (r = 0.72 and r = 0.70; p < 0.001), and BNP (r = 0.60 and r = 0.60; p < 0.001). In conclusion, soluble TNF receptors are increased in proportion to the severity of congestive heart failure and may reflect the current status of congestive heart failure rather than the level of left ventricular dysfunction.

Adult↗
PubMed1997

Suppressive effects of Y-24180, a long-acting antagonist for platelet-activating factor, on allergic pulmonary eosinophilia in mice.

We studied the effects of (+/-)-4-(2-chlorophenyl)-2-[2-(4-isobutylphenyl)ethyl]-6,9-dimethy l-6H-thieno[3,2-f][1,2,4]triazolo[4,3-a][1,4]diazepine (Y-24180), a long-acting antagonist for platelet-activating factor (PAF), on antigen-induced eosinophil infiltration and interleukin-5 (IL-5) release in the bronchoalveolar lavage fluid (BALF) of mice. Mice actively sensitized with ovalbumin (OA) were challenged by injecting intratracheally OA 3 times every fourth day. Both the number of eosinophils and level of IL-5 were significantly increased in the BALF 24 hr after the last OA challenge. Either Y-24180 or prednisolone was orally administered once a day for 10 days beginning one day before the first OA challenge. WEB2086, another PAF antagonist, was orally administered once or twice a day for 10 days. Y-24180 (0.3 - 3 mg/kg) suppressed the eosinophil infiltration in a dose-dependent manner and suppressed the IL-5 release at the highest dosage. Prednisolone (10 mg/kg) significantly suppressed both the eosinophil infiltration and IL-5 release. In contrast, WEB2086 affected neither the eosinophil infiltration nor IL-5 release when administered once a day (10 - 100 mg/kg/day). This drug never affected the IL-5 release but significantly suppressed eosinophil infiltration even when administered twice a day (30 - 200 mg/kg/day). These results indicate that the suppressive effect of Y-24180 on allergic pulmonary eosinophilia is due to not only to its long-lasting PAF-antagonism but also due to its suppressive effect on IL-5 release.

Animals↗
PubMed1997

Efficient expression of mono- and diacylglycerol lipase gene from Penicillium camembertii U-150 in Aspergillus oryzae under the control of its own promoter.

The gene, mdlA, coding for mono- and diacylglycerol lipase from Penicillium camembertii U-150 was expressed efficiently in Aspergillus oryzae under the control of its own promoter. The gene product was secreted into the culture medium with a highest productivity of 1 g/liter and correctly processed at both N- and C-termini. KEX2-like processing was suggested to occur at the C-terminus in both A. oryzae and P. camembertii. Specific activity and substrate specificity of the purified recombinant protein were also almost the same to that of native protein but the extent of N-glycosylation in the recombinant protein was about half of that of the native protein. The presence of introns did not seem to affect the gene expression. The mdlA expression was induced by lipids and regulated transcriptionally in A. oryzae as well as P. camembertii. Promoter deletion analysis showed that the region between the positions at -382 and -554 bp from the translation initiation point was important to the higher expression of mdlA. The promoter sequence of mdlA was compared to that of the Geotrichum candidum lipase gene, which is also reported to be inducible by lipids, with three commonly observed oligonucleotide sequences.

Aspergillus oryzae↗
PubMed1997

[A case of multiple endocrine neoplasia type I with primary hyperparathyroidism, prolactin secreting pituitary microadenoma and gastrin secreting duodenal carcinoid].

A case of MEN type I in a 64-year-old man is reported. He had undergone partial duodenectomy because of gastric ulcer and multiple duodenal polyps (gastrin secreting carcinoid). Blood examination revealed hypercalcemia, hyperPTHemia, and hyperprolactinemia. Neck US and CT showed enlargement of 4 parathyroid glands. Brain MRI revealed the microadenoma in left pituitary gland. Total parathyroidectomy with auto-transplantation in the left forearm were performed. Histological examination showed the hyperplasia of the parathyroid. Three and a half year after parathyroidectomy, there was no evidence of recurrence of gastrin secreting tumor and hyperparathyroidism, and enlargement of pituitary microadenoma. This is the first MEN type I case in Japan which have detected 3 endocrine tumors clinically with gastrin secreting duodenal carcinoid.

Adenoma↗
PubMed1997

[A case of a surgically treated extracranial internal carotid artery saccular aneurysm].

Extracranial internal carotid artery aneurysm is rare. Most cases are due to spontaneous or traumatic dissection of the cervical internal carotid artery. Here we report a case of surgically treated extracranial internal carotid artery (ICA) aneurysm. A 74-year-old man noticed a pulsatile mass just below the left mandibular angle. Intravenous digital subtraction angiography revealed multiple aneurysms in the systemic arteries, including the aortic arch, abdominal aorta and left extracranial ICA. It was decided to treat the aneurysms of the aortic arch and of the abdominal aorta conservatively. Cerebral angiography, however, showed a saccular aneurysm which projected latero-posteriorly at the C2 level of the left extracranial ICA. Although the patient had no previous ischemic event, we decided to treat this aneurysm surgically in view of the risk of cerebral ischemia caused by intraaneurysmal thrombus formation or rupture of the aneurysm by neck injury. The operation was performed under mild hypothermal general anesthesia. Electroencephalography was carried out during the operation. A skin incison was made from the anterior border of the sternocleidomastoid muscle to the pretragal region to expose the parotid gland. This skin incision, elevation of the parotid gland and division of the digastric muscle were useful for exposing the distal portion of the extracranial ICA. After trapping of the aneurysm, it was punctured and collapsed by aspiration and the dome was excised at its neck. The ICA was then reconstructed by suturing the cut neck of the aneurysm. Patency of the ICA was confirmed by postoperative angiography. The postoperative course was smooth except for hoarseness, which was caused by damage to a minor branch of the vagus nerve during exposure of the aneurysmal dome.

Aged↗
PubMed1997

Lethal drug interactions of sorivudine, a new antiviral drug, with oral 5-fluorouracil prodrugs.

Rats were orally co-administered sorivudine (SRV: 1-beta-D-arabinofuranosyl-(E)-5-(2-bromovinyl)uracil), a new oral antiviral drug for herpes zoster, with the oral anticancer drug tegafur (FT: 1-(2-tetrahydrofuryl)-5-fluorouracil) as a prodrug of 5-flourouracil (5-FU) once daily to investigate a toxicokinetic mechanism of 15 Japanese patients' deaths recently caused within a brief period by the drug interaction of these drugs. All the rats showed extremely elevated levels of 5-FU in plasma and tissues, including bone marrow and small intestine, and died within 10 days, whereas the animals given the same dose of SRV or FT alone were still alive over 20 days without any appreciable toxic symptom. Before their death, there was marked damage of bone marrow, marked atrophy of intestinal membrane mucosa, marked decreases in white blood cells and platelets, diarrhea with bloody flux, and severe anorexia as reported with the Japanese patients. Data obtained by in vivo and in vitro studies strongly suggested that (E)-5-(2-bromovinyl)uracil generated from SRV by gut flora was reduced in the presense of NADPH to a reactive form by hepatic dihydropyrimidine dehydrogenase (DPD), a key enzyme determining the tissue 5-FU levels, bound covalently to DPD as a suicide inhibitor, and markedly retarded the catabolism of 5-FU.

Administration, Oral↗
PubMed1997

[A case of simultaneous bilateral carotid occlusion].

Cases of bilateral cartoid occlusion have often been reported in the literature, but most of them were not examples of simultaneous bilateral carotid occlusion. Simultaneous bilateral cartoid occlusion appears to be rare, so we report one such case in this paper. A 68-year-old woman suddenly became unconscious, and was delivered to our hospital by ambulance. On arrival, she was comatose and showed decerebrate rigidity upon pain stimulation. Results of CT scan were normal, but cerebral angiography showed bilateral internal carotid artery occlusion at the carotid bifurcation. The patient was treated with urokinase and osmotic diuretics, but these were not effective and she died on the eleventh day after admission. Autopsy revealed that the bilateral internal carotid artery was occluded by fresh thrombi at the carotid bifurcation. The mitral valve was thickened by fibrous adhesion, and this was thought to indicate mitral stenosis. MRI before onset had shown flow void sign in the bilateral internal carotid artery. From the clinical course, and radiological and autopsy findings, we consider this case to be one of simultaneous bilateral carotid occlusion due to cardiogenic thrombi. Previous cases of bilateral carotid occlusion are reviewed and discussed.

Aged↗
PubMed1997

[Familial astrocytoma associated with von Recklinghausen's disease: report of two cases].

Two cases of astrocytoma associated with von Recklinghausen's disease (neurofibromatosis type; NF-1) were reported. The first case wes a 60-year-old man who had been diagnosed as von Recklinghausen's disease on the basis of skin findings. Magnetic resonance imaging (MRI) showed a tumor in the left temporal lobe. Partial removal was performed with neuronavigator, and because of the existence of Rosenthal fiber the histological diagnosis was pilocytic astrocytoma. Radiation therapy was performed. The second case was a 6-year-old boy suffering from headache and left hemiparesis including his face. MRI showed a tumor with a cyst in the right thalamus and obstructive hydrocephalus. Initially CT-guided stereotactic biopsy was performed, and the histological diagnosis, on the basis of increased cellularity, pleomorphism and nuclear atypia without necrosis or vascular proliferation, was anaplastic astrocytoma. Radiation and chemo-immuno therapy were carried out after V-P shunt. It is well known that von Recklinghausen's disease (NF-1) is often associated with optic glioma (5-36%). In the literature, the glioma seldom occurs in other parts of the brain, supratentorial glioma especially is rare. Only two familial cases of supratentorial glioma associated with von Recklinghausen's disease have been reported. The prognosis of supratentorial glioma associated with NF-1 was poor in these reports. In this paper, the diagnostic and therapeutic problems are discussed.

Astrocytoma↗
PubMed1997

Experimental study of laparoscopic gastrectomy: intracorporeal Billroth I gastroduodenostomy.

Laparoscopic gastrectomy is now performed only for a partial resection that does not require anastomosis. We have been studying laparoscopic gastrectomy using the Billroth I method in animal models, and here we describe the surgical procedure. The gastrocolic ligament is divided along with the greater curvature, and the right gastroepiploic vessels are divided at their point of origin. The lesser omentum is dissected and the gastric antrum is divided using an endoscopic linear cutter. The anvil of a circular stapler is inserted into the duodenal bulb through the pyloric ring and ligated. An instrument for creating a pursestring suture is applied to the anterior wall of the stomach, and the circular stapler is inserted into the gastric lumen. Then Billroth I gastroduodenal anastomosis is performed with the stapler. After this anastomosis, four endoscopic linear cutters are applied to divide the gastric body, and the partial gastrectomy is completed. This animal experimental study has revealed that the Billroth I gastrectomy is easy to perform using a circular stapler and several linear cutters under laparoscopic guidance.

Animals↗
PubMed1997

[Magnetic resonance imaging of brainstem lesions in a case of neuro-Behçet disease].

We reported a 28-year-old man with multiple lesions in the brainstem which were clearly identified and followed up with MRI. He had been treated for Behçet uveitis using cyclosporine and colchicine during the past 5 years, and he acutely presented with fever and headache, followed left hemiparesis, dysarthria and dysphagia. MRI on admission revealed multiple lesions in the ventral pontine region which showed mixed-intensity on T1WI, high-intensity on T2WI and enhancement with Gd-DTPA. His clinical symptoms spontaneously and gradually improved, but more rapidly improved due to additional administration of corticosteroid. The lesions in the brainstem became smaller and finally rudimentary during two months after the onset of neurological symptoms.

Adrenal Cortex Hormones↗
PubMed1997

[Bellini duct carcinoma of the kidney: a case report].

A rare case of Bellini duct carcinoma of the kidney is reported. A 44-year-old woman with macroscopic hematuria was referred to our hospital. the clinical diagnosis was a right renal tumor with direct invasion to the liver. Radical nephrectomy and segmental hepatectomy were performed. Histopathological examination revealed papillary growth of atypical cells different from the usual histological pattern of renal cell carcinoma. The histological diagnosis of Bellini duct carcinoma was confirmed by the positive immunohistochemical staining with a collecting duct marker (UEA-1), and distal tubule marker (EMA) and negative staining with a proximal tubule marker (Leu-M1).

Adult↗
PubMed1997

Lethal drug interactions of sorivudine, a new antiviral drug, with oral 5-fluorouracil prodrugs.

Rats were orally co-administered sorivudine (SRV: 1-beta-D-arabinofuranosyl-(E)-5-(2-bromovinyl)uracil), a new oral antiviral drug for herpes zoster, with the oral anticancer drug tegafur (FT: 1-(2-tetrahydrofuryl)-5-fluorouracil as a prodrug of 5-fluorouracil (5-FU) once daily to investigate a toxicokinetic mechanism of 15 Japanese patients' deaths recently caused within a brief period by the drug interaction of these drugs. All the rats showed extremely elevated levels of 5-FU in plasma and tissues, including bone marrow and small intestine, and died within 10 days, whereas the animals given the same dose of SRV or FT alone were still alive over 20 days without any appreciable toxic symptom. Before their death, there was marked damage of bone marrow, marked atrophy of intestinal membrane mucosa, marked decreases in white blood cells and platelets, diarrhea with bloody flux, and severe anorexia as reported with the Japanese patients. Data obtained by in vivo and in vitro studies strongly suggested that (E)-5-(2-bromovinyl)uracil generated from SRV by gut flora was reduced in the presense of NADPH to a reactive form by hepatic dihydropyrimidine dehydrogenase (DPD), a key enzyme determining the tissue 5-FU levels, bound covalently to DPD as a suicide inhibitor, and markedly retarded the catabolism of 5-FU.

Animals↗
PubMed1997

Analysis of molecular heterogeneity of Dahl/Iwai salt-sensitive rats and salt-resistant rats.

Molecular evidence, using DNA fingerprint analyses, of extensive genetic heterogeneity between spontaneously hypertensive rats (SHR) and Wistar-Kyoto rats (WKY) and even within some of the WKY colonies has been reported. Thus we investigated the genetic relations between Dahl S and R rats newly inbred by Dr. Iwai. Genomic DNA was isolated from the liver of four Dahl S and four Dahl R rats, digested with the restriction enzyme HinfI or AluI, and separated in 1.2% agarose gel by electrophoresis. Then, DNA fingerprinting was performed by Southern blot analysis using the human myoglobin 33.6 minisatellite probe. Bands were detected in an alkaline phosphatase reaction system. Within the same strains, there was no heterogeneity of these fingerprinting patterns. The S and R rats shared 82% of the bands in the HinfI-digested DNA and 93% of those in the AluI-digested DNA. These shared values were much greater than the reported value (54%) between SHR and WKY from Charles River Laboratories. These newly inbred Dahl S and R rats may be appropriate, although still limited, experimental animals for investigating the pathophysiology of salt-sensitive hypertension.

Animals↗
PubMed1997

[Inhibitory effect of oral administration of Takusya on calcium oxalate crystallization in human whole urine].

We previously reported that Takusya had the inhibitory effect on in vitro calcium oxalate crystallization and in vivo stone formation in an animal model and it could be a prophylactic agent against calcium oxalate stone formation. We studied the effect of Takusya on calcium oxalate crystallization in human urine. Takusya (500 mg/day and 1,000 mg/day) was administered to 16 healthy men for 3 days and then 24-hour urine samples were collected to measure the urinary excretion of calcium, phosphate, magnesium, uric acid, creatinine, citric acid and oxalic acid. The urine samples before the administration of Takusya was used as a control. The size and distribution of crystals, which were formed in the urine samples by adding calcium chloride and sodium oxalate, were measured using the Coulter counter technique. Urinary magnesium excretion was significantly reduced by 1,000 mg/day of Takusya compared with the control (p < 0.05). The growth of crystals was significantly inhibited by 500 mg/day of Takusya in the large crystal formers whose urine created crystals more than 3.5 microns before the administration of Takusya (p < 0.05). These findings suggested that Takusya inhibited the growth of crystals formed in human urine.

Administration, Oral↗