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Biomedical subjects

M Takeda

Publications and source records attributed to M Takeda.

At least 595 records · Page 33Linked to original sources
PubMed1993

Antibody against the carboxyl terminus of the F2 subunit of Sendai virus fusion glycoprotein inhibits proteolytic activation.

Rabbit antibody, F2C12, was prepared against a synthetic peptide of 13 amino acids corresponding to the C-terminus of the F2 subunit of Sendai virus F protein. F2C12 was shown to bind specifically to the F2 subunit, irrespective of proteolytic cleavage of the F protein. F2C12 did not affect the infectivity, hemolytic, and cell fusion activities of activated virus, but F2C12 did inhibit proteolytic cleavage of the precursor F0 to subunits, F1 and F2, by trypsin, factor Xa from chick embryos and Tryptase Clara from rat lungs. When F2C12 was added to the chorioallantoic cavity of chick embryos, cleavage activation of Sendai virus was inhibited. Intranasal administration of F2C12 to Sendai virus-infected rats suppressed activation and multiplication of progeny virus in the lungs. These results indicate that proteolytic cleavage of the F protein, with a single arginine residue at the cleavage site, occurs extracellularly in the allantoic cavity of chick embryos and in the bronchial lumen of rats.

Allantois↗
PubMed1993

Expression of the neural cell adhesion molecule (NCAM) during second- and third-molar development in the mouse.

Distribution of the neural cell adhesion molecule (NCAM) during the development of the mandibular second- and third-molars of the mouse was studied by indirect immunofluorescence techniques. At the initial stage, NCAM was intensely expressed by the mesenchymal cells surrounding the dental lamina, and by the cap stage NCAM expression by the mesenchymal cells became restricted to the dental follicle. After that, in addition to the follicular mesenchyme, some cells in the basal part of the dental papilla showed NCAM-immunoreactivity for a while after the hard tissue formation had started. During root formation, the follicular cells lost NCAM first from the level of the cervical root and later from the coronal part, while an additional NCAM positive area appeared deep in the dental papilla. Even after the teeth had erupted, NCAM was expressed in the tissue surrounding the apical root and in the pulp core. During the initial and bud stages, the pattern of NCAM expression in the second and third molars was different from that in the first molar, where NCAM was found only after the late bud stage; while from the cap stage onward, it changed in the same sequence as in the first molar. The different pattern of NCAM expression implies that there is a difference in developmental events between the early stages of the first and the other two molars. On the other hand, the common sequence of NCAM expression in the tooth germs later than the cap stage suggests that NCAM plays an essential role in the formation of the basic structure of the teeth and periodontal tissues.

Animals↗
PubMed1993

Expression of neural cell adhesion molecule (NCAM) during the first molar development in the mouse.

NCAM, the neural cell adhesion molecule, was immunolocalized in the mandibular first molar tooth germ of the mouse. NCAM was first detected in the tooth germ of the late bud stage, where only the cells in the outer part of the condensed mesenchyme (primitive dental follicle) exhibited faint immunoreactivity. The entire dental follicle was intensely immunostained for NCAM from cap stage to the stage when root formation started. During root formation, NCAM disappeared from the follicular tissue surrounding the cervical root as well as from the part covering the crown top. This loss of NCAM proceeded in the direction of the root apex, but even after the tooth had achieved functional occlusion, NCAM was still expressed by the mesenchymal cells adjacent to the root apex. On the other hand, NCAM was negative in the dental papilla until birth. After birth, NCAM-immunoreactivity appeared in the basal portion of the dental papilla, but this NCAM-positive area gradually diminished in width during the root elongation. Instead, another NCAM-positive zone appeared in the core of the pulp during root formation. Even in the tooth that had already erupted, the pulp core contained cells that were strongly positive for NCAM immunostaining. In addition to its expression in the above two mesenchymal cell lineages, NCAM was transiently expressed by epithelial components of the tooth germ, some of the cells of the dental lamina and the enamel organ. The results suggest that NCAM participates in several processes of tooth development.

Aging↗
PubMed1993

Assessment of exercise-induced alterations in body composition of patients with coronary heart disease.

The purpose of this study was to determine the effects of exercise habituation on body composition and anthropometric characteristics in cardiac patients. The subjects, comprising 20 patients with coronary heart disease, aged 43-69, participated in our supervised exercise programme for 38.0 (SD 12.5) weeks while in hospital. The intensity of most exercise was set at the lactate threshold. Analyses of the data indicated that small but significant reductions were observed in body mass (mb) [-1.4 (SD 1.8) kg], abdominal girth [-1.4 (SD 2.6) cm], chest girth [-1.3 (SD 1.8) cm], body mass index [-0.6 (SD 0.7)], and skinfold thicknesses at all the sites measured. As expected, fat-free mass, derived from either bio-electrical impedance (BI) or a skinfold technique with commonly used regression equations, remained essentially unchanged, while there were significant decreases in body fat (BF) and %BF. The absolute amount of change in mb (i.e. delta mb) was significantly associated with delta abdominal girth (r = 0.506), delta BF estimated by the BI technique (r = 0.476), and delta BF estimated by the skinfold technique (r = 0.451). Although the period of the exercise programme [38.0 (SD 12.5) weeks] varied greatly among subjects, it was found not to be associated with delta mb and alterations in body composition. We concluded that aerobic exercise induced significant decreases in BF and many anthropometric variables, independent of the duration of exercise, and that a combination of abdominal girth, BI and/or skinfold measurements would be advantageous in estimating primarily exercise-induced alterations in BF in cardiac patients.

Adipose Tissue↗
PubMed1993

Assessment of high-energy phosphorus compounds in the rat kidney by in situ 31P nuclear magnetic resonance spectroscopy: effect of ischemia and furosemide.

31P nuclear magnetic resonance (NMR) spectroscopy of the in situ rat kidney was performed by a surface coil method, and the effects of ischemia and furosemide infusion were assessed. 31P NMR spectra of the kidney subjected to 30 min of ischemia returned completely to the pre-ischemic level after 60 min of reperfusion. But the 31P NMR spectra after 60 min of ischemia did not recover, even after 120 min of reperfusion. Levels of beta-ATP and inorganic phosphate (Pi) decreased and the chemical shift of Pi increased after intravenous infusion of furosemide. This increase in chemical shift might signal an alkalotic change in intracellular pH. Furosemide infusion prior to ischemia is thought to protect the kidney from injury induced by 60 min of warm ischemia. The chemical shift of Pi returned to the pre-ischemic level earlier than beta-ATP and Pi. In conclusion, according to the findings of 31P NMR spectroscopy, furosemide infusion prior to ischemia may be effective in protecting the kidney against ischemic injury. But the change in Pi peak and the causes of the dissociation of Pi and beta-ATP should be examined further.

Animals↗
PubMed1993

Body surface potential maps in patients with familial amyloid polyneuropathy.

The purpose of this study was to evaluate the characteristics of body surface potential maps in patients with cardiac amyloidosis. The study population consisted of 30 patients with familial amyloid polyneuropathy and 50 age-matched normal volunteers. The patients were classified into one of the following three stages: stage I, peripheral neuropathy limited to the lower limbs; stage II, neuropathy involving both the lower and upper limbs; and stage III, bedridden because of extensive progressive neuropathy. Electrodes for the body surface potential maps were placed at 87 points (59 anterior and 28 posterior) on the chest. To analyze these body surface electrocardiograms, isopotential maps, isochrone maps, and isointegral maps were used. The mean values of the positive potential were significantly lower in the advanced stage (1.9 +/- 0.2 mV in stage I, 1.0 +/- 0.2 mV in stage II, and 0.7 +/- 0.2 mV in stage III). Prolongation of ventricular activation time was observed on the anterior and lateral chest. The mean QRST isointegral maps of the patients in the advanced stage of cardiac amyloidosis showed a large negative area over the anterior and left lateral chest, the positive areas were small and their potentials were very low. In addition, 18 (60%) of the 30 patients had a multipolar pattern in the QRST isointegral maps. The changes of the body surface potential maps correlated with clinical staging and echocardiographic findings.

Adult↗
PubMed1993

Anti-HIV (human immunodeficiency virus) activity of sulfated paramylon.

Sulfated derivatives of paramylon, a water-insoluble (1-3)-beta-D-glucan from Euglena gracilis, significantly inhibited the cytopathic effect of human immunodeficiency virus (HIV-1, HIV-2) and the expression of HIV antigen in cultured MT-4, MOLT-4 cells and human peripheral blood mononuclear cells. Native paramylon, N,N-dimethylaminoethyl paramylon, N,N-diethylaminoethyl paramylon, 2-hydroxy-3-trimethylammoniopropyl paramylon chloride, and carboxymethyl paramylon had little or no anti-HIV activity. The anti-HIV activity of the sulfated paramylon derivatives depended on the number of sulfate groups, and the molecular weight. Paramylon sulfate significantly inhibited HIV-1 binding to MT-4 cells. The anti-coagulant activity of the sulfated paramylon derivatives also depended on the number of sulfate groups, but was generally lower than that of dextran sulfate. The results point to the potential of paramylon sulfate in the treatment of HIV infection.

Animals↗
PubMed1993

The efficacy of radiation therapy for a malignant melanoma in the mucosa of the upper jaw: an analytic study.

An analysis has been made of the effect of radiation therapy in 28 patients with a malignant melanoma (Stage I: 18 cases; Stage II: 10 cases) in the mucosa of the upper jaw. Treatment had been provided by one of the following methods: intraoral mold (10 cases), interstitial brachytherapy (two cases), intraoral electron therapy (nine cases), or external irradiation (seven cases). The results have shown that the survival rate for all 28 patients was 25%, and that the survival rate for stage I patients treated by intraoral electron or brachytherapy was 47%. The primary tumor control rate in percentages was 79% (22/28) in all 28 radiotherapy patients; 92% (11/12) for tumors treated by a mold or an interstitial implant; 67% (6/9) for tumors treated by an intraoral cone; and 71% (5/7) for tumors treated by external irradiation with or without surgery. A neck metastasis that was found in 19 patients was treated by surgery, radiotherapy, and/or immunochemotherapy, and the result was successful in nine patients. The major factor in the failure of treatment was a distant, metastatic dissemination. This analysis revealed that radiotherapy has achieved similar or better results than surgery and may be advocated for the management of a localized malignant melanoma in the mucosa of the upper jaw.

Adult↗
PubMed1993

Ureteropelvic junction obstruction with renal pelvic calcification: a case report.

Calcification in the wall of the renal pelvis is rare. We report on a 65-year-old man with hydronephrosis secondary to ureteropelvic junction obstruction with renal pelvic calcification. Calcium deposit was found in the wall of the severely dilated renal pelvis. Pathological examination revealed a damaged and hyalinized fibrous renal pelvic wall and serum calcium level was normal. Thus, we speculated that this calcification was dystrophic. Chronic extensive dilatation with intermittent hemorrhage of the renal pelvic wall may have caused this dystrophic renal pelvic calcification.

Aged↗
PubMed1993

Immunohistochemical detection of intercellular adhesion molecule-1 (ICAM-1) and major histocompatibility complex class I antigens in seminoma.

Expression of intercellular adhesion molecule-1 (ICAM-1) and major histocompatibility complex (MHC) antigens, and characterization of tumor-infiltrating mononuclear cells (TIM) were examined immunohistologically in 10 specimens of seminoma. ICAM-1 and MHC antigens were not detected on normal spermatogenic cells. ICAM-1 and MHC class I antigens were variably expressed in 7 and 9 seminomas, respectively, whereas class II antigens were not detected. Although the degree of expression of ICAM-1 and MHC antigens was not correlated with any clinical or histopathological factors, neither of the antigens was detected on an anaplastic seminoma. Various numbers of TIM were detected in all of the seminoma, and comprised mainly T cells bearing the lymphocyte function-associated antigen (LFA)-1. No significant correlation was noticed between the degree of lymphocyte infiltration and ICAM-1 or MHC antigen expression. Although ICAM-1 and MHC class I antigens were expressed in seminoma, possibly facilitating an anti-tumor reaction of host, their expression remained low in several cases, despite marked lymphocyte infiltration within the tumor.

Adult↗
PubMed1993

Scales for mental state and daily living activities for the elderly: clinical behavioral scales for assessing demented patients.

In the diagnosis, treatment, and care of dementia patients in the senile stage, comprehensive evaluation of ability in daily life and mental function is needed. Using a simple behavioral rating scale for the mental states (NM scale) and activities of daily living (N-ADL) of the elderly, we evaluated 250 elderly subjects. According to the NM scale, the scores for subjects in whom the severity was clinically diagnosed were as follows: normal, 50-48; borderline, 47-43; mild dementia, 42-31; moderate dementia, 30-17; and severe dementia, 16-0. Screening for dementia and determining its severity were readily accomplished using the NM scale, and basic activities in the daily life of the elderly could be evaluated effectively using the N-ADL. There was a significant correlation (r = 0.863) between the Hasegawa dementia scale and the NM scale (p < 0.001), a significant correlation (r = -0.947) between intellectual function scores of the GBS scale and the NM scale, and a significant correlation (r = 0.944) between motor function score of the GBS scale and the N-ADL score. Evaluations of daily life activities can be made not only by psychiatrists and clinical psychologists, but by nonspecialists as well, because they are based on data obtained by observation of daily life behaviors; thus, assessment is appropriate both in clinical settings and in places of living.

Activities of Daily Living↗
PubMed1993

Clinicopathology of kidneys from brain-dead patients treated with vasopressin and epinephrine.

Studies were made on the biochemical and pathological conditions of kidneys of 20 brain-dead patients who were maintained for 0 to 48 days after brain death by administration of vasopressin and epinephrine. Twenty specimens were obtained by percutaneous biopsy or at autopsy. The biochemical and pathological degrees were compared with those on the day of brain death (day 0). Biochemical tests on day 0 indicated that they showed the diuretic phase of prerenal failure, and then glomerular hyperemia was extensive. Renal function recovered on day 1 and remained almost normal during the 14 day period. Their urine retained high levels of sodium and osmolarity for days 0 to 14, with mild hyponatremia and hypo-osmolarity of the plasma. Tubulointerstitial nephritis gradually became extensive. There was no significant change in the degrees of mesangial widening, mesangial cell proliferation or hyalinosis. Arterial intimal proliferation was gradually extensive after day 3 and glomerular endothelial proliferation was gradually extensive after a week. Brain-dead patients have been mostly reported to develop diabetes insipidus, but our brain-dead patients did not show any manifestation of this disease. We suggest that constant natriuresis and continuing high level of urine osmolarity might have been caused by prerenal renal failure, brain death followed by neurogenic impairment, high level of serum vasopressin, or interstitial nephritis.

Adult↗
PubMed1993

A carcinoid tumor of the rectum removed by strip biopsy.

In a 29-year-old male complaining of constipation, total colonoscopy revealed a 5 mm yellowish submucosal tumor at a distance of 6 cm from the anal ring. The histologic diagnosis of specimens obtained by biopsy was rectal carcinoid tumor and transanal ultrasonography revealed the tumor localization within the submucosal layer in the rectum. A strip biopsy was performed. Histopathological examination confirmed the diagnosis and ascertained complete excision. Rectal carcinoid tumors should be removed completely and strip biopsy may be a suitable procedure for removal of rectal submucosal tumors less than 10 mm in diameter.

Adult↗
PubMed1993

Laparoscopic adrenalectomy for primary aldosteronism: a new operative method.

From January 17, 1992 to January 16, 1993, laparoscopic adrenalectomy was performed in 7 patients (3 men, 4 women) with primary aldosteronism ranging in age from 35 to 65 years (mean 48.7 years). Five of the adrenal lesions were on the left side and two were on the right. Five to six trocar-sheath units were used, and adrenal tumors were successfully removed with adjacent normal adrenal glands in all patients. The operative time ranged from 165 to 572 min (mean 302 min), operative blood loss was between 50 and 450 ml (mean 217.2 ml), and there was no major complication. In conclusion, laparoscopic adrenalectomy is a safe alternative operative method for primary aldosteronism, although application of this technique to other types of adrenal lesions remains to be examined.

Adrenal Gland Neoplasms↗
PubMed1993

Arachidonic acid and its metabolites increase Cai in cultured rat oligodendrocytes.

Fluorescence measurements of intracellular calcium (Cai) were made on cultured rat spinal cord oligodendrocytes (OLGs) using the dye fura-2. Exposure of OLGs to arachidonic acid (AA) (5-50 microM) elicited a concentration-dependent increase in Cai that was derived mainly from extracellular Ca2+. AA at 50 microM also released Ca2+ from intracellular stores. The response to AA was not decreased by nifedipine or by inhibition of Na(+)-Ca2+ exchange. AA-induced Ca2+ influx pathway was permeable to Mn2+ and Co2+ but not to Ba2+ and was not markedly influenced by depolarization, suggesting that AA activates a voltage-independent, not strictly selective, Ca2+ channel. The Cai response to AA was partially attenuated in the presence of indomethacin, indicating that the Cai response was mediated in part by cyclooxygenase products of AA. However, the AA-induced Cai response far exceeded that induced by prostaglandins and was mimicked by linoleic acid. We conclude that AA modulates Cai of OLGs via two mechanisms: 1) indirectly via cyclooxygenase pathway and 2) directly via membrane lipid-protein interaction.

Animals↗
PubMed1993

Volume and agonist-induced regulation of myosin light-chain phosphorylation in glomerular mesangial cells.

We investigated whether cell volume decrease per se can activate intracellular mechanisms leading to mesangial cell contraction. For this purpose, we applied hyperosmotic stress to cultured glomerular mesangial cells and examined the effects on phosphorylation of myosin light chain (MLCP). Compared with control cells, hyperosmotic stress (390 mosmol/kg) attained by either NaCl or raffinose significantly increased MLCP to 140.7 +/- 7.0% (n = 5) and 134.8 +/- 7.7% (n = 4), respectively, in parallel with a decrease in the cell volume. This increase was comparable to that achieved by the following agonists: arginine vasopressin (AVP, 100 nM; n = 5) and endothelin-1 (ET, 10 nM; n = 5). By using two-dimensional tryptic phosphopeptide mapping, contribution of myosin light-chain kinase (MLCK) and protein kinase C (PKC) to the observed phosphorylation was examined by identifying phosphorylation at serine-19 (by MLCK) and at serine-1 or serine-2 (by PKC). Under resting conditions, relative distribution of phosphorylation between MLCK and PKC sites was 60.1 +/- 8.4 and 39.9 +/- 8.4%. The relative contribution by these enzymes remained similar during hyperosmotic stress or agonist stimulation. Since cytosolic Ca2+ concentration ([Ca2+]i) is an important determinant of MLCP, we also examined [Ca2+]i in these settings. While AVP and ET-induced a characteristic transient spike in [Ca2+]i, hyperosmotic stress caused a gradual and modest increase in [Ca2+]i. These studies show that, in mesangial cells, reduction in cell volume induces MLCP through mechanisms distinct from those involved in agonist-induced events.

Animals↗
PubMed1993

Regulation of Na(+)-3HCO3- cotransport in rabbit proximal convoluted tubule via adenosine A1 receptor.

We investigated the role of adenosine A1-receptor in the regulation of basolateral Na(+)-3HCO3- cotransporter in the rabbit proximal convoluted tubule (PCT) microperfused in vitro by monitoring basolateral membrane potential and intracellular pH. FK-453, a highly specific A1 antagonist, inhibited basolateral HCO3- conductance in a concentration-dependent manner (10(-10)-10(-5) M). Other A1 antagonists, 8-cyclopentyl-1,3-dipropylxanthine (DPCPX) at 10(-5) M and theophylline at 10(-3) M, also had similar effects. N6-cyclohexyladenosine (CHA) at 10(-7) M attenuated the effect of low concentration (10(-8) M) of FK-453. Either enhancement of the degradation of adenosine by 0.1 U/ml adenosine deaminase (ADA) or inhibition of adenosine release from the cells by 10(-6) M S-(4-nitrobenzyl)-6-thioinosine (NBTI) mimicked the effects of A1 antagonists. These observations suggest that endogenous adenosine is released from PCT cells and stimulates Na(+)-3HCO3- cotransporter. Both 10(-4) M 8-(4-chlorophenylthio)-adenosine 3',5'-cyclic monophosphate (CPT-cAMP) and 10(-6) M forskolin also inhibited basolateral HCO3- conductance. Both 10(-6) M FK-453 and 10(-4) M CPT-cAMP decreased the initial rate as well as the magnitude of intracellular acidification induced by reduction of peritubular HCO3- concentration from 25 to 0 mM. Neither 10(-6) M FK-453 nor 10(-7) M CHA changed intracellular Ca2+ concentration as measured by fura-2 fluorescence. These results indicate that adenosine might stimulate HCO3- exit across the basolateral membrane through Na(+)-3HCO3- cotransporter by decreasing intracellular cAMP via A1-receptor activation.(ABSTRACT TRUNCATED AT 250 WORDS)

Adenosine↗