Search PubMed⌕ Search

Biomedical subjects

T Arai

Publications and source records attributed to T Arai.

At least 253 records · Page 14Linked to original sources
PubMed1999

Changes in hyaluronidase, acrosin, and N-acetylhexosaminidase activities of dog sperm after incubation.

Hyaluronidase, acrosin and N-acetylhexosaminidase activities were examined in sperm collected from 12 beagle dogs and in culture medium after 0.5 hr and 7 hr of sperm incubation. The activities of the three enzymes were significantly higher at 7 hr than at 0.5 hr (P < 0.05, 0.01), and the increases were associated with sperm capacitation. It was considered that the three enzymes in the dog sperm are related to fertilization by reason of the findings of the release of these enzymes from the sperm into the medium after 7 hr of incubation.

Acrosin↗
PubMed1999

p-Chloroamphetamine (PCA) suppresses ingestive behavior in male rats.

Ingestive behavior was activated in male rats by intraoral intake and intake from a bottle of 1-M solution of sucrose. Intraperitoneal injection of p-chloroamphetamine (PCA), releasing central 5-hydroxytryptamine (5-HT) from serotonergic nerve terminals, inhibited ingestion of the sucrose solution. Significant inhibition of sucrose intake by PCA was observed at 1.25 and 2.5 mg/kg dose in a bottle intake test, and at 5.0 mg/kg dose in an intraoral intake test. These findings suggested that 1.25 and 5.0 mg/kg of PCA suppressed appetitive ingestive behavior and consummatory ingestive behavior in male rats, respectively.

Administration, Oral↗
PubMed1999

Accomplishment of time-interval activation of esterase A4 by simple removal of pin fraction.

In the seasonal cycle of the silkworm Bombyx mori, an ATPase called esterase A4 (EA4) is thought to measure time interval as a diapause-duration timer. To address the mechanism by which EA4 measures the time, we present a simple EA4 screening method. By the method, EA4 activity can be assessed with a short incubation at 25 degrees C without the need to purify the enzyme further. The method largely overcomes methodological problems that remain unanswered. Besides, the results obtained by the method establish that the time measurement is based on the moment when the time-holding factor(s) PIN (peptidyl-inhibitory needle) is removed. EA4 may originally be a complex with PIN, and external time cues such as winter cold may induce the dissociation of the complex, which in turn results in the timer activation of EA4.

Adenosine Triphosphatases↗
PubMed1999

[Pathologic evaluation of the main cause of death in Japanese centenarians].

A total of 42 Japanese centenarians (9 males & 33 females) autopsied in Tokyo Metropolitan Geriatric Hospital during 22 years (1975-1996) were clinico-pathologically examined to determine details of the main cause of death. The main cause of death of the 42 cases were sepsis (16 cases), pneumonia (14 cases), suffocation (4 cases), heart failure (4 cases), cerebrovascular disorder (2 cases) and malnutrition (2 cases). Most pneumonias were caused aspiration of foreign bodies, and the origins of sepsis were pyelonephritis (7 cases), biliary tract infection (3 cases), necrotic lesions of the intestine due to ileus, ischemia and pseudomembranous colitis (3 cases) and indwelling vein catheter (3 cases). Malignant neoplasms were observed in 16 cases (38%), and 5 of them had 2 or 3 lesions. Thus, the total number of lesions of malignant neoplasms were 22, as follows; colonic cancer (36%), urinary bladder cancer (14%), lung adenocarcinoma (9%), gastric cancer (9%), malignant lymphoma (9%) and others. However, none of these malignant neoplasms were directly related with the cause of death. All 42 centenarians died not of simple "senile decay", but due to diseases.

Aged↗
PubMed1999

[Interstitial pneumonitis associated with Sweet's syndrome in the elderly].

Sweet's syndrome occurring during the course of interstitial pneumonitis in a 70-year-old woman was encountered. She was admitted because of dyspnea on exercise, dry cough and interstitial shadow on chest x-ray. Lung biopsy, together with other findings confirmed interstitial pneumonitis. Five days after admission, genital ulcer and aphtha on the oral mucosa were detected and exudative erythema appeared on her right shoulder, chest and back. Histological examination of the skin lesions demonstrated numerous nutrophilic infiltration in the upper dermis, indicating Sweet's syndrome. The skin eruption rapidly disappeared on treatment with colchicine. Although six months after admission interstitial pneumonitis caused respiratory failure, treatment with prednisolone and cyclophosphamide was effective. Serological and immunological tests demonstrated hyper-gammaglobulinemia and positive reaction for anti SS-A antibody. Pathological examination of the lip revealed numerous lymphocyte infiltrates around the duct of the minor salivary gland, suggesting Sjögren's syndrome as the background disease of Sweet's syndrome and interstitial pneumonitis. This evidence indicating that even in elderly patients, skin lesions of Sweet's syndrome may reveal the background disease.

Aged↗
PubMed1999

Glutathione monoethyl ester and inhibition of the oxyhemoglobin-induced increase in cytosolic calcium in cultured smooth-muscle cells.

OBJECT: The mechanism of arterial vasoconstriction caused by oxyhemoglobin production after subarachnoid hemorrhage was investigated. METHODS: Using a fluorescent Ca++ indicator (fura-2 acetoxymethyl ester), the change in the cytosolic intracellular Ca++ concentration, [Ca++]i. was measured in cultured rat vascular smooth-muscle cells exposed to oxyhemoglobin and other substances. Oxyhemoglobin induced transient elevation of smooth-muscle cell [Ca++]i in either the presence or absence of ethyleneglycol-bis (beta-aminoethylether)-N,N'-tetraacetic acid, indicating that Ca++ released by oxyhemoglobin was derived from [Ca++]i stores. In contrast, methemoglobin had no effect on the smooth-muscle cells. Exposure of the cells to reactive oxygen species generated by xanthine plus xanthine oxidase yielded the same results as with oxyhemoglobin, that is, transient elevation of smooth-muscle cell [Ca++]i. Procaine (a Ca++ channel blocker) failed to inhibit the oxyhemoglobin-induced elevation of [Ca++]i. Ryanodine (a Ca++ channel opener) plus oxyhemoglobin caused markedly greater elevation of [Ca++]i than ryanodine alone, whereas thapsigargin (an adenosine triphosphate [ATP]-dependent Ca++ pump inhibitor) plus oxyhemoglobin had no additional effect when compared with thapsigargin alone. The oxyhemoglobin-induced elevation of [Ca++]i could be blocked by an Fe++ chelator (ferene), but not by an Fe chelator (deferoxamine mesylate). Treatment with either dithiothreitol or glutathione monoethyl ester markedly inhibited the oxyhemoglobin-induced elevation of [Ca++]i. CONCLUSIONS: These results indicate that Fe++-catalyzed hydroxyl radicals generated from oxyhemoglobin-derived free radicals induce the elevation of [Ca++]i by inhibiting the ATP-dependent Ca++ pump rather than the Ca++ channels in the sarcoplasmic reticulum and that thiols may prevent Ca++ pump inactivation by inhibiting the oxidation of membrane sulfhydryl groups.

Animals↗
PubMed1999

EXTL3/EXTR1 alterations in colorectal cancer cell lines.

We previously demonstrated that metastasis-related tumor suppressor gene(s) may exist on chromosome 8p21-22 on allelotype analysis of early colorectal carcinomas (CRC) with lymph node metastasis. Here, we searched for target gene(s) in this chromosomal region in the UniGene database. The EXTL3 (also called EXTR1) gene was selected as a candidate because of its homology to EXT1 and EXT2, putative tumor suppressor genes. We screened 12 CRC cell lines for mutations by means of polymerase chain reaction (PCR)-single strand conformation polymorphism. Three cell lines showed EXTL3 mutations, all of which were located within exon 3 and caused amino acid substitutions. Reverse transcription-PCR analysis showed that the EXTL3 expression was lacking in 1 of the 12 colorectal cancer cell lines. Although there is still no definitive evidence that EXTL3 is a tumor suppressor gene for CRC, these data suggest that inactivation of the EXTL3 gene may at least offer a selective growth advantage for some CRC cell lines.

Adenomatous Polyposis Coli↗
PubMed1999

[A case of Guillain-Barrè syndrome with severe sciatica preceding motor paralysis in the lower extremities].

A 62-year-old man was referred to our clinic for a three-day history of intractable sciatic pain. The pain was so severe that he could not sleep for days. Initially there was no neuronal sign except for the pain, nor any abnormality in lumbar CT and MRI. Cerebrospinal fluid sampled on the third hospital day revealed elevated protein (192 mg.dl-1) with minimal cells. On the 4th hospital day motor weakness of lower extremities appeared and he developed complete flaccid paraplegia in a week without loss of sensation. He was diagnosed as Guillain-Barrè syndrome. For the relief of this pain, intermittent injection of 4 ml 0.25% bupivacaine from lumbar epidural catheter was started on the admission day. By using patient controlled analgesia system, we could treat his repetitive demand timely and well control the pain. The leg weakness started to recover slowly from the 13th hospital day and at the same time the pain started to diminish rapidly in a few days. From the 20th hospital day he started to have rehabilitation in walking and recovered completely in two months without complication. We should remember that sudden onset of severe pain is one of early symptoms of Guillain-Barrè syndrome.

Analgesia, Epidural↗
PubMed1999

Variations in the gene for vacuolating toxin, vacA, in Japanese isolates of Helicobacter pylori.

Each of 284 strains of Helicobacter pylori which had been isolated in Japan was shown, by use of the polymerase chain reaction (PCR), to be positive for the vacA genes. The amplified vacA genes generated by PCR were classified into six classes (five for the clinical isolates, and one which corresponded to the standard strains). Endoscopic analysis revealed that cases of gastritis were most likely to be associated with class D, while none were associated with class A. The patterns of products of PCR obtained from the Japanese isolates were compared with theoretical patterns derived from sequences of vacA which had been reported previously. The nucleotide sequences of amplified fragments of vacA from representative strains in each class were determined and compared with those of previously reported vacA genes.

Bacterial Proteins↗
PubMed1999

A fiber-optic measurement system of light scattering to evaluate embryo viability: model experiment using a latex sphere suspension and mouse embryos.

In this study, we tested the efficacy of a fiber-optic light scattering system developed by us to measure mitochondrial size and particle density in embryos in order to establish a non-invasive method of evaluating human embryo viability for in vitro fertilization and embryo transfer. Particle size was determined by comparing the measured angular distribution of the light scattering intensity with that of the theoretical distribution using a 1.0 micron latex sphere suspension and mouse embryos. The measured light scattering pattern of the latex suspension was found to agree closely with the theoretically derived pattern. The measured light scattering pattern of the mouse embryo was similar to the calculated pattern of spheres, the diameter of which was equivalent to that of the mitochondria. Therefore, the measured light scattering is thought to be derived mainly from the mitochondria in the embryo. The relationship between light scattering intensity and latex particle density was also examined in order to estimate the detectable range of mitochondrial particle density. Since the detectable range of the particle density obtained in our study (1.4 x 10(6) - 1.4 x 10(11) particles/ml) was greater than the known mitochondrial particle density in human embryos (1.0 x 10(9) - 1.0 x 10(11) particles/ml), we believe that this mitochondrial particle density can be measured using our system. We concluded that it is possible to use our simple system as a non-invasive method for evaluating human embryo viability.

Animals↗
PubMed1999

[The effect of olprinone administered after cardio-pulmonary bypass during open heart surgery, evaluated by its plasma concentrations and hemodynamic changes].

Plasma concentrations and hemodynamic effects of olprinone were evaluated in seventeen patients undergoing open heart surgery. The patients were randomized into the bolus group (15 micrograms.kg-1 bolus dose +0.1 microgram.kg-1.min-1 infusion, n = 9) and the non-bolus group (0.1 microgram.kg-1.min-1 infusion, n = 8). Plasma concentrations and hemodynamic variables were measured before CPB (cardiopulmonary bypass; baseline), 5, 60 min after weaning from CPB, and 3, 6 hours after the end of surgery. Plasma concentrations in the non-bolus group were significantly lower than those of bolus group at any point except for 3 hours after the end of surgery. In the bolus group, increases in the cardiac index and stroke volume index were significantly higher compared with the non-bolus group. From these results we conclude that olprinone given in bolus (15 micrograms.kg-1) followed by continuous infusion (0.1 microgram.kg-1.min-1) is efficacious and safe during weaning from CPB.

Aged↗
PubMed1999

[Complete responses in patients with unresectable liver metastases from colorectal cancer with weekly high-dose 5-FU plus one-shot CDDP HAI].

Thirty-two patients with unresectable liver metastases from colorectal cancer, treated by intermittent hepatic arterial infusion of high-dose 5-FU combined with CDDP, were assessed. As a result of this treatment, the overall response rate was 65.6%, and eight patients (25%) which contained three autopsy cases revealed a complete response. The mean doses of 5-FU and CDDP which was administered in the eight patients were 24.3 g and 65 mg, respectively. One of the eight patients showed complete disappearance of liver metastasis on the CT scan after arterial infusion of 4.5 g of 5-FU, and necrosis or disappearance of the tumor was present in more than 2/3 of the whole lesion. Autopsy showed focal or zonal necrosis, distorted reconstruction of architecture, and cholangiolitis of the liver which were administered more than 15 g of 5-FU. Intermittent hepatic arterial infusion of high-dose 5-FU combined with CDDP is proved to be a useful locoregional chemotherapy for liver metastasis from colorectal cancer. We should evolve new treatment modalities for extrahepatic metastases, as HAI combined with the systemic chemotherapeutic regimen.

Aged↗
PubMed1999

[Complications related to hepatic arterial infusion chemotherapy for liver metastasis from colorectal cancer].

UNLABELLED: We evaluated the complications of hepatic arterial infusion (HAI) chemotherapy in patients (pts) with hepatic metastasis from colorectal cancer. The subjects consisted of 61 pts with hepatic metastasis from colorectal cancer, who were treated by combined chemotherapy with 5-FU and CDDP weekly or continuously. Indwelling route of catheter: 30 via gastroduodenal artery (GDA) at the time of laparotomy ('LP'), 21 via femoral artery (FA) and catheter tip in PHA ('PHA'), 10 via FA and catheter tip is inserted with steel coil into the GDA ('GDA-coil'). Complications resulting in interruption of therapy occurred in 19 pts (31%), and the 'GDA-coil' method had a lower rate of complication than others. There was no difference in the incidence rate of complications between the two chemotherapy regimens. The complications of this therapy were: 8 (13%) cases of hepatic arterial occlusion, 3 (5%) cases of duodenal ulcer, 4 (7%) cases of catheter tip dislocation, 2 (3%) cases of catheter tip dislocation to the duodenal bulb, and 1 (2%) case of liver abscess. Hepatic arterial occlusion occurred frequently in LP. Up to 67% of patients with duodenal ulcer had hepatic arterial occlusion at the same time. All pts with catheter tip dislocation were 'PHA', and all pts with catheter tip dislocation to the duodenal bulb were 'LP'. IN CONCLUSION: 1. The best indwelling route for the catheter is by the 'GDA-coil' method. 2. To diagnose complications soon, regular CTA or DSA is necessary.

Adult↗
PubMed1999

Application of low-intensity ultraviolet irradiation to the treatment for pharmacological vasoconstriction via a percutaneous transluminal approach.

We applied low-power ultraviolet (UV) laser irradiation via a thin flexible optical fiber to an in vivo model of vasospasm using an intravascular transluminal approach. The surgically exposed left femoral arteries of a rabbit were constricted by norepinephrine. A quartz fiber of 400 microm in diameter was introduced into the artery via the right common carotid artery through a 2.5F catheter. The femoral artery lumen was then irradiated with a helium-cadmium laser (wavelength 325 nm, output power 8 mW) through the fiber for 30 s. The UV irradiation increased the mean luminal diameter by 85% in comparison to the precontracted state, while the increase was only 45% in a sham operation. A histopathologic examination revealed no thermal damage and an intact internal elastic lamina. These results suggest that intravascular transluminal irradiation with a low-power UV laser may thus have potentially clinical applications to reverse acute arterial vasospasm.

Angiography↗
PubMed1999

Clinical application of a fiberscope for periodontal lesions: case reports.

In dentistry, the endoscope has generally been used to visualize inaccessible areas, e.g., inside root canals or coronal surfaces of teeth; however, it has not been used in periodontally diseased lesions. In this study, a newly designed fine fiberscope (0.8- to 1.0-mm outer diameter) with an irrigation system was used to visualize root surfaces and periodontal tissues affected by periodontal disease. The fiberscope was inserted through fistulas, periodontal pockets, or root furcations in 5 patients to provide clear operational views without the obstruction of blood or soft tissues. The irrigation system of the endoscope effectively allowed differentiation of hard and soft tissues as well as restorative materials. The fiberscope system developed in this study was effective for diagnosis, for enhancing visualization for periodontal surgery, and for treating lesions such as fistulous tracts or furcation lesions.

Adult↗