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Biomedical subjects

K Takeuchi

Publications and source records attributed to K Takeuchi.

At least 793 records · Page 44Linked to original sources
PubMed1992

Stimulation by capsaicin of gastric alkaline secretion in anesthetized rats.

Effects of mucosal application of capsaicin on alkaline secretion were examined in the stomachs of anesthetized rats and compared with those in the duodenum. The stomach (acid secretion was inhibited by omeprazole given i.p.) or the duodenum was perfused with saline (pH 4.5); both the pH of the perfusate and transmucosal potential difference (PD) were continuously monitored; and the HCO3- output was determined by the pH change. Under these conditions, the mucosal application of capsaicin (0.3-6 mg/ml for 30 min) caused significantly increased pH and HCO3- output in a concentration-related manner in both tissues, while PD increased in the duodenum and decreased in the stomach. The HCO3- stimulatory action of capsaicin was markedly attenuated by sensory deafferentation, significantly mitigated by prior administration of indomethacin, and exhibited a marked tachyphylaxis after the repeated exposure at a high concentration (6 mg/ml). None of these treatments had any effect on the pH, PD and HCO3- responses induced by prostaglandin E2 (300 micrograms/kg, i.v.) in these tissues. These results indicate that mucosal application of capsaicin increased the gastroduodenal HCO3- output by stimulation of capsaicin-sensitive sensory neurons. This action may be in part mediated by endogenous prostaglandins.

Afferent Pathways↗
PubMed1992

Effects of nitric oxide synthase inhibitors on gastric alkaline secretion in rats.

The effects of NG-nitro-L-arginine methyl ester (L-NAME), the nitric oxide (NO) synthase inhibitor, on gastric HCO3- secretion were examined in anesthetized rats. Intravenous administration of L-NAME (1, 2.5, 5 mg/kg) increased HCO3- secretion in a dose-related manner. This effect of L-NAME was mimicked by NG-mono-methyl-L-arginine (50 mg/kg, i.v.) and was antagonized significantly by concurrent administration of L-arginine but not D-arginine (200 mg/kg, i.v.). These results indicate that gastric HCO3- secretion is stimulated by inhibition of NO biosynthesis.

Amino Acid Oxidoreductases↗
PubMed1992

Induction of gastric lesions by 2-deoxy-D-glucose in rats following chemical ablation of capsaicin-sensitive sensory neurons.

Effects of chemical ablation of capsaicin-sensitive sensory nerves on functional and mucosal ulcerogenic responses to 2-deoxy-D-glucose (2DG) were investigated in the rat stomach, in comparison with those of indomethacin, a prostaglandin (PG) biosynthesis inhibitor. Intravenous injection of 2DG (200 mg/kg) followed by infusion of this agent (100 mg/kg/hr, i.v.) significantly increased gastric acid secretion and motility, but rarely induced macroscopic damage in the gastric mucosa of normal conscious rats. Chemical ablation of capsaicin-sensitive sensory nerves or pretreatment with indomethacin (5 mg/kg, s.c.) did not significantly affect the acid secretory and motility responses to 2DG, but induced severe hemorrhagic lesions in the stomach within 4 hr. Gastric mucosal blood flow (GMBF) determined by laser Doppler flowmetry under anesthetized conditions did not consistently change during 2DG treatment in any of these three groups, but the rise in GMBF in response to mucosal acidification (0.2 N HCl) was significantly inhibited in the animals pretreated with indomethacin or following chemical deafferentation. We conclude that functional ablation of capsaicin-sensitive sensory neurons, similar to the PG deficiency, increases the gastric mucosal vulnerability during 2DG infusion (acid hypersecretion and hypermotility due to vagal excitation), resulting in hemorrhagic lesions, and that the mechanism may be accounted for at least partly by the impairment of gastric mucosal blood flow response to mucosal acidification.

Animals↗
PubMed1992

Secretion of mono- and diacylglycerol lipase from Penicillium camembertii U-150 by Saccharomyces cerevisiae and site-directed mutagenesis of the putative catalytic sites of the lipase.

Yeast cells carrying intronless mono- and diacylglycerol lipase (MDGL) genes, constructed by recombination of the genomic gene and cDNA, secreted MDGL into the culture supernatant. Most of the yeast MDGL were extensively glycosylated while they had a similar glyceride specificity to that of native MDGL. Site-directed mutagenesis was used to directly confirm the involvements in enzyme activity of the presumptive amino acid residues to form the catalytic center of MDGL. These residues were conserved in the primary structure alignment of a lipase family from filamentous fungi. Mutant lipase proteins in which Ser83, Ser145, or His259 was replaced with glycine were secreted by yeast transformants as inactive proteins. Mutant proteins replacing Asp199 with glycine or asparagine were not detected in the culture supernatant. Replacing other two highly conserved aspartic acids (at positions 232 and 243) with glycine did not render the enzyme inactive. These results indicate that Ser83, Ser145, and His259 in MDGL, are essential to enzyme activity. Asp199 is also likely to be involved.

Amino Acid Sequence↗
PubMed1992

Phosphoinositide hydrolysis and calcium mobilization induced by vasopressin and angiotensin II in cultured vascular smooth muscle cells.

The cellular action of vasoconstrictive hormones, angiotensin II (AII) and Arg8-vasopressin (AVP), on vascular smooth muscle (VSM) in cultured VSM cells from rat mesenteric artery was studied. Both AII and AVP specifically induce a transient increases in cytosolic free calcium independent of extracellular calcium or calcium channels activated by high potassium depolarization in VSM cells loaded with Fura-2. Vasoconstrictive hormones induce a dose-dependency with formation of inositolphosphates. Analysis using high pressure liquid chromatography has shown that AVP stimulates rapid and transient increases in inositol 1,3,4-trisphosphate, inositol 1,4,5-trisphosphate and inositol 1,3,4,5-tetrakisphosphate within 1 minute. Moreover, a laser-excitation fluorescence system reveals high calcium concentration sites in subsarcolemmal region. These results indicate that, unlike voltage-dependent calcium influx across the cell membrane, AII and AVP induce receptor-mediated increases in cytosolic free calcium via phosphoinositide hydrolysis creating an intracellular messenger for calcium release from intracellular calcium stores.

Angiotensin II↗
PubMed1992

Effect of sulindac on prostaglandin synthesis in human and in cultured rat renal and vascular smooth muscle cells.

To examine the hypothesis that sulindac does not inhibit renal prostaglandin (PG) synthesis, we investigated the effects of sulindac and other nonsteroidal anti-inflammatory drugs on PG synthesis in human and in cultured rat renal and vascular smooth muscle (VSM) cells. In 7 patients with chronic glomerular disease, creatinine clearance and proteinuria were not changed by sulindac but were significantly reduced by diclofenac sodium. However, urinary excretion of PGE2 was decreased by both drugs. In cultured glomerular mesangial (GM), renal papillary collecting tubule (RPCT) and VSM cells from mesenteric artery, indomethacin, tiaprofenic acid, aspirin and ibuprofen inhibited both basal and arachidonic acid (AA)-stimulated PG synthesis dose-dependently. Although sulindac sulfoxide, at the same concentrations, inhibited both basal and AA-stimulated PGE2 synthesis in RPCT cells, it was less potent to inhibit PGI2 synthesis in VSM cells or PGE2 synthesis in GM cells. Active form sulindac sulfide inhibited PG synthesis in all types of cells but its inactive form sulfone did not. We conclude that sulindac inhibits renal PG synthesis but has little effect on renal function. This may be explained by its relatively weak potency on glomerular or vascular PG synthesis inhibition possibly due to the different biotransformation of the sulfoxide to the active sulfide in these cells.

6-Ketoprostaglandin F1 alpha↗
PubMed1992

Disseminated cryptococcosis presenting with adrenal insufficiency and meningitis: resistant to prolonged antifungal therapy but responding to bilateral adrenalectomy.

A case of disseminated cryptococcosis with features of primary adrenal insufficiency and meningitis in an immunocompetent host is presented. Despite antifungal chemotherapy, neither meningitis nor bilateral adrenal gland enlargement was improved. Aspiration biopsy of the adrenal gland revealed necrotic tissue with numerous fungi, suggesting that the adrenal glands were the focus of the persistent fungemia. Removal of bilateral adrenal glands led to improvement by making the patient more sensitive to antifungal chemotherapy.

Adrenal Gland Diseases↗
PubMed1992

Antigen reduces nasal transepithelial electric potential differences and alters ion transport in allergic rhinitis in vivo.

The change of ion transport in acute allergic reactions in vivo was studied by measuring the nasal transepithelial potential difference (PD) in patients with nasal allergy to Japanese cedar pollens. Comparison of nasal PD in the pollen season revealed a lower PD in the allergic patients than in the normal control subjects. We challenged the patients with allergen in the non-pollen season and measured the time course change of nasal PD and rate of inhibition of PD by amiloride and indomethacin. Nasal PD reached the lowest value 15 min after nasal allergen challenge. Percent inhibition of PD by amiloride was greater without the allergen challenge than it was in those patients after allergen challenge (51.7% versus 29.4%, p less than 0.01). Indomethacin did not change PD without allergen challenge, whereas it depressed nasal PD by 25.1% after allergen challenge. These results suggest that decreased sodium absorption and increased chloride secretion occur in local allergic reactions. Both changes may contribute to the increase in fluid transport towards the lumen, and this may lead to abnormalities of nasal secretion during acute allergic reactions.

Administration, Intranasal↗
PubMed1992

[Evaluation of subjective happiness in the elderly using a visual analogue scale of happiness in correlation with depression scale].

A Visual analogue scale of happiness (VAS-H) was applied to elderly population in a community to evaluate their subjective quality of life. The study population consisted of 313 elderly people aged over 75. Using a 20 cm visual analogue scale (VAS), VAS-H was measured by asking subjects to place a single vertical mark on a horizontal line at a point corresponding to their current subjective degree of happiness judged from health condition and psycho-social background as a whole; The VAS-H was anchored on the left and with the words "-100%; unhappiest" and on the right end with the words "+100%; happiest". The scores of VAS-H (%) were obtained by multiplying the distance (cm) from the zero point to the vertical line by 10. To determine the characteristics of VAS from the standpoint of the quality of life, we compared VAS with scores of two kinds of established depression scale, because the mood which was assessed by these scale was supposed to be an important factor of the quality of life. The results of the simultaneously assessed Geriatric Depression Scale (GDS), and Zung's depression scale (SDS) which was obtained 1 year before for the same subjects were compared with that of VAS-H. The score of VAS-H had a significantly negative correlation with both GDS and SDS. In conclusion, VAS-H was a simple and useful method to evaluate degree of subjective happiness which was one factor of quality of life in the elderly people.

Aged↗
PubMed1992

[Evaluation of subjective happiness in the elderly using a visual analogue scale of happiness to analyze the effect of life style and neurobehavioral function on subjective happiness].

The effects of activity of daily living (ADL), physical conditions, social environmental factors and neurobehavioral functions on subjective happiness were investigated in 313 elderly subjects. The degree of subjective happiness was measured using visual analogue scale of happiness (VAS-H). There was significant relationship between VAS-H and ADL. The VAS-H score had weak but significant correlation with physical conditions and neurobehavioral functions. The social environmental factors, especially economical conditions, family relationships and group behavior had a significant correlation with VAS-H. In conclusion, in apparent healthy elderly people, the subjective degree of happiness was not related to ADLs, but to social environment and information physical conditions.

Activities of Daily Living↗
PubMed1992

[Application of visual analogue scale of happiness to elderly Himalayan highlanders].

Visual analogue scale of happiness (VAS-H) was applied to elderly Himalayan highlanders to investigate the influence of life-style and socio-cultural background on subjective happiness. The score of "VAS-H" and neuropsychological function tests in 733 Himalayan highlanders who belonged to 5 separate villages were compared with those in 313 Japanese elderly subjects. The places of study consisted of 4 villages (Khalimabad; K, Gulmit; G, Pasu; P, Shimshal; S) in Hunza area in Pakistan, and Namche Bazar; N in Nepal. Degree of modern civilization was highest in K, followed by N, G, P and lowest was that in S by historical and sociological aspects. The mean VAS-H sore in Himalayan highlanders and the degree of modern civilization in the area was in inverse proportion. Himalayan elderly women showed a significant lower score on VAS-H compared with elderly Himalayan men or elderly Japanese subjects. The VAS-H score in the Japanese elderly correlated significantly with the stability of posture and walk, and that of Himalayan highlanders correlated significantly with manual skill. In conclusion, the life style or socio-cultural background strongly affected subjective happiness in the elderly. The VAS-H was useful in comparing subjective happiness in different cultures.

Adult↗
PubMed1992

[Primary hemangiopericytoma of the chest wall--a case report].

An extremely rare case of a primary hemangiopericytoma of the chest wall was reported. A 40-year-old female without any complaints was detected to have an abnormal shadow in the right chest wall on a chest X-ray film. The tumor was 2.6 x 2.2 x 2.0 cm in size and was resected together with the 8th rib which adhered to the tumor. Postoperative pathohistological examination led to the diagnosis of hemangiopericytoma. Postoperative course was uneventful, and the patient is now doing well and has had no recurrence for 11 months since the operation. A brief review was made on 9 cases collected from the literature.

Adult↗
PubMed1992

[Studies on criteria for clinicopathological diagnosis of allergic granulomatous angiitis (AGA)].

Comparative studies in the evaluation of criteria for clinicopathological diagnosis of AGA which was proposed by Japanese Health and Welfare Ministry (JHWM) in 1988 and American College of Rheumatology (ACR) in 1990 were conducted. Twenty seven Japanese patients with AGA and 231 Japanese controlled patients with polyarteritis nodosa (PAN) and Wegener's granulomatosis (WG) were used as material patients who had been provided a second questionnaire in 1984 sponsored by the JHWM. As a result, the JHWM criteria was 85.2% in sensitivity and 96.5% in specificity, which was superior to the ACR criteria being 74.1% in sensitivity and 93.9% in specificity. These results were due to the low sensitivity and low accuracy in paranasal sinus abnormality and pulmonary infiltrates which were included in the ACR criteria. Furthermore, the JHWM criteria could be diagnosed as AGA using not only the histopathological findings but by the clinical symptoms alone. The controlled patients who were overdiagnosed as AGA using ACR criteria were thought to be included as patients with WG. On the other hand, the controlled patients who were overdiagnosed as AGA using JHWM criteria were thought to be included as patients with overlap syndrome of AGA and PAN. Accuracy of polyneuropathy, muscle weakness, melena and pretibial edema were over 60%, indicating that these clinical symptoms were available for vasculitis symptoms of the JHWM criteria.

Churg-Strauss Syndrome↗
PubMed1992

[Influences of magnesium sulfate on maternal calcium metabolism in preterm labor].

The effects of intravenous magnesium sulfate tocolysis on calcium metabolism were studied in 10 patients with preterm labor. A loading dose of magnesium sulfate (4g) was administered intravenously maintenance intravenous infusion of magnesium sulfate (1g per hour). All patients simultaneously received 50 micrograms ritodrin per minutes by intravenous infusion. Serum magnesium increased from 1.91 +/- 0.06mg/dl to 4.6 +/- 0.71mg/dl at 30 minutes (p < 0.01) and it remained relatively high. The fall in serum calcium corrected by serum total protein was most rapid during the first 30 minutes, from 9.04 +/- 0.47mg/dl to 8.3 +/- 0.27mg/dl (p < 0.01). Urinary excretion of magnesium, represented as the calcium/creatinine ratio, rose markedly from 0.05 +/- 0.01 to 3.18 +/- 0.8 at an hour (p < 0.01) and thereafter remained higher than the baseline level. Changes in urinary excretion of calcium paralleled those of urinary evcretion of magnesium. Serum parathyroid hormone rose from 118 +/- 42.2pg/ml to 294 +/- 121pg/ml at 6 hours (p < 0.05). Serum 1 alpha,25-(OH)2D3-rose from 89.3 +/- 44.2pg/ml to 126 +/- 38.7pg/ml (p < 0.05). Serum calcitonin showed no significant change. These findings indicate that correction of hypocalcemia mainly depends on secretion of parathyroid hormone in the early stage, and thereafter depends on the cooperative action of parathyroid hormone and 1 alpha,25-(OH)2D3.

Adult↗
PubMed1992

[Extramedullary diseases as presenting features of aleukemic acute monocytic leukemia].

We present a case of acute monocytic leukemia presenting with extramedullary disease clinically resembling lymphoma. A 36 year-old man presented with arthralgia and was found to have skin eruption, nasopharyngeal mass, hepatosplenomegaly and superficial lymphadenopathy. The biopsies of those lesions as well as bone marrow revealed infiltration of CD45 positive large atypical cells and were interpreted as malignant lymphoma. At that time blood film showed leuko-erythroblastic picture, but no atypical cells were noted. He was treated with CHOP followed by VEPA chemotherapy and achieved partial remission. Four months later headache and double vision occurred with the same atypical cell in the cerebrospinal fluid. The cells were identified as monoblasts by cytochemistry and immunophenotype. The diagnosis of aleukemic acute monocytic leukemia was made and its CNS involvement was successfully treated with chemotherapy with DHAP and intrathecal MTX. However, two months later, blasts finally appeared in the peripheral blood and the patient died of multiorgan failure eight months after presentation. The blasts were positive for T cell markers (CD2, 4, 8) and NK marker (NKH-1) as well as monocytic markers. This finding, together with those by other investigators, may indicate the association between these immunophenotypes and extramedullary manifestations of acute monocytic leukemia.

Adult↗
PubMed1992

Preimplantation genetic analysis.

Advanced reproductive technologies have afforded us access to human preembryos, allowing the possibility of preimplantation genetic diagnosis of certain genetic diseases. This paper thoroughly reviews both the micro-manipulation and molecular biologic aspects of this new and exciting branch of medicine. In addition, some of the moral and ethical considerations relating to preembryo genetic diagnosis are discussed.

Biopsy↗