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Biomedical subjects

K Ando

Publications and source records attributed to K Ando.

At least 469 records · Page 26Linked to original sources
PubMed1991

[Studies on plasma immunoreactive human brain natriuretic peptide (hBNP) levels in patients with congestive heart failure and present forms of hBNP in human cardiac ventricle].

By using a specific radioimmunoassay (RIA) for human brain natriuretic peptide (hBNP), we measured immunoreactive hBNP (ir-hBNP) in plasma from patients with congestive heart failure (CHF). There appeared to be relationship between the enhanced ir-hBNP secretory activity and the severity of the failing heart as well as that of immunoreactive human atrial natriuretic peptide (ir-hANP). However, the secretion of ir-hBNP was augmented much more than that of ir-hANP in sever CHF patients. Gel permeation chromatography coupled with the RIA revealed that ir-hBNP in human ventricle is composed with gamma-hBNP and hBNP (1-32) as well as that of human atrium. However, we found differences of the gamma-hBNP/hBNP (1-32) ratio in atrial and ventricular tissues. These findings suggest that the hBNP secretion mechanism differ in the two areas of human heart.

Adult↗
PubMed1991

[A specific and highly sensitive radioimmunoassay of human brain natriuretic peptide].

We established specific and highly sensitive radioimmunoassay (RIA) for the detection of human brain natriuretic peptide (BNP), and confirmed the presence of BNP-like immunoreactivity (BNP-LI) in human circulating blood and the heart. The antibody used in this RIA did not react any known human atrial natriuretic peptide (ANP). Gel permeation chromatography coupled with the RIA revealed that BNP-LI in atrium is composed with high molecular BNP and low molecular BNP. Furthermore, dominant form of BNP-LI in human plasma was thought to be low molecular BNP. Mean concentration of BNP-LI in plasma from normal subjects was 5.9 pg/ml, which was about 5 times lower than that of ANP-LI. Mean concentration of BNP-LI in human cardiac atrium was 45.6 ng/mg protein, which was about 40-fold lower than that of ANP-LI. Furthermore, concentration of BNP-LI in human cardiac ventricle was in a range of 0.1-4.8 ng/mg protein, being about 1/20 that of cardiac atrium. These data suggest that BNP synthesized in human heart and secreted into circulation.

Heart Atria↗
PubMed1990

Production of endothelin-1 by rat cultured mesangial cells.

We investigated whether ET-1 is synthesized by and released from mesangial cells. ET-1-like immunoreactivity (LI) released into medium increased time-dependently under a serum-free condition. The amounts of ET-1-LI released into the medium was augmented in the presence of fetal calf serum. Reverse-phase HPLC profile of the conditioned media revealed a major component coeluting with standard ET-1. Northern blot analysis of poly(A) +RNA extracted from mesangial cells showed a single major band corresponding to the size of preproET-1 mRNA (2.3 kb). These findings demonstrate that ET-1 is synthesized by and released from rat mesangial cells and suggest a possibility that it acts on their own cells as an autocrine factor.

Animals↗
PubMed1990

Eye movements in acute, chronic, and remitted schizophrenics.

Eye movements in 10 acute schizophrenics, 50 chronic schizophrenics, 20 remitted schizophrenics, 25 methamphetamine psychotics, 21 temporal lobe epileptics with left-sided spike focus (l-focus), 12 temporal lobe epileptics with right-sided spike focus (r-focus), and 50 normal controls were examined with an eye mark recorder while they viewed geometric figures. The eye movements while viewing an original "S"-shaped figure for 15 sec were analyzed. Each schizophrenic group and methamphetamine psychotics had significantly less eye fixations than the normal controls and temporal lobe epileptics (r-focus and l-focus). The chronic schizophrenics had significantly shorter mean eye scanning length (MESL) than the other six groups. Each subject was then shown two other figures slightly different from the original and was requested to compare them with the original. After comparing them, the subjects were asked the question, "Are there any other differences?" The 5-sec eye movements during the response to this question were scored using the Responsive Search Score (RSS). The schizophrenic groups had a significantly lower RSS than the nonschizophrenic patient groups and the normal controls. In the chronic schizophrenics, there was a significant negative correlation between the RSS and negative symptoms. These results suggest that the MESL can be an indicator of a chronic process of schizophrenia, and that lowering of the RSS may be a nosologically specific indicator for schizophrenia.

Acute Disease↗
PubMed1990

Presence of endothelin-1-like immunoreactivity in human cerebrospinal fluid.

By use of radioimmunoassay (RIA) specific for endothelin-1 (ET-1), we have studied whether ET-1-like immunoreactivity (LI) exists in human cerebrospinal fluid (CSF). Human CSF from patients with old cerebrovascular disease contained far greater amounts of ET-1-LI (28 +/- 1.3 pg/ml, n = 9) than normal human plasma. Reverse-phase HPLC coupled with ET-1 RIA revealed a single major ET-1-LI component in human CSF extract coeluting with standard ET-1. These data suggest ET-1 is a neuropeptide secreted from neural tissues in humans.

Aged↗
PubMed1990

Pro-thyrotropin-releasing hormone concentrations in the brain of ataxic mice.

Concentrations of pro-thyrotropin-releasing hormone (pro-TRH) were studied in the brain of the Weaver ataxic mouse, the Purkinje cell degenerative mouse (pcd-ataxic mouse), the Staggerer ataxic mouse and the C3H mouse. The brain tissue was dissected into 7 parts, e.g., hypothalamus, cerebrum, thalamus, striatum, brain stem, cerebellum and cervical spinal cord. Pro-TRH concentrations in each part of the brain were measured by radioimmunoassay. Pro-TRH concentrations in the brain of Weaver ataxic mice, pcd-ataxic mice and Staggerer ataxic mice were significantly higher in the thalamus, brain stem, cerebellum and cervical spinal cord. Pro-TRH concentrations in the hypothalamus, striatum and cerebrum of ataxic mice did not differ from those of controls. The elution profile of acetic acid extracted cerebellum of ataxic mice on Sephadex G-50 was identical to that of synthetic pro-TRH. These findings suggest that changes in pro-TRH concentrations in the brain may play a pathophysiological role in ataxic mice.

Animals↗
PubMed1990

Determination of manganese concentrations in the spinal cords from amyotrophic lateral sclerosis patients by inductively coupled plasma emission spectroscopy.

Continuing analytical studies on environmental factors in the foci of amyotrophic lateral sclerosis (ALS) in the Kii Peninsula of Japan and Guam, and metal analysis using neutron activation analysis in central nervous system (CNS) tissues from ALS cases indicate that chronic exposure to metals such as aluminum and manganese, together with a deficiency of minerals such as calcium and magnesium, may play a causative role in the neurodegeneration seen in ALS. An accurate and simple method for detecting minerals and trace metals in small, fresh samples of CNS tissue is necessary in order to follow the pathogenetic behavior of these elements. In this paper, we describe a method for measuring manganese (Mn) content in CNS tissue samples taken from mouse brain using inductively coupled plasma (ICP) spectroscopy and present results of the determination of Mn contents in spinal cord samples from ALS cases using the same method. ICP emission spectroscopy is considered to have great advantage for the simultaneous determination of elements in small, fresh CNS samples because of its simplicity and convenience, and the elimination of the necessity to use potentially dangerous acids. Results showed that the mean concentration of Mn in a mouse brain (0.56 microgram/g) and in human spinal cords (0.39 microgram/g wet weight in the anterior horn, 0.37 in the lateral fasciculus, 0.39 in the posterior horn and 0.28 in the posterior fasciculus) were compatible with results previously reported using other methods. In ALS spinal cords, the mean content of Mn was similar to that of controls, but the distribution differed. In the ALS cases, Mn contents were higher in the anterior horn and lateral fasciculus than in the posterior horn.(ABSTRACT TRUNCATED AT 250 WORDS)

Amyotrophic Lateral Sclerosis↗
PubMed1990

Content and distribution of vasoactive intestinal polypeptide (VIP) in cavernous tissue of human penis.

Penile erection is controlled by a valvular structure in the helicine artery in humans. The opening and closing of this valve are believed to be regulated by the autonomic nervous system, especially through the release of vasoactive intestinal polypeptide (VIP). We determined the content of VIP in cavernous tissue in 18 impotent patients and in 5 normal controls by radioimmunoassay, and we examined the distribution of VIP-ergic nerve fibers in cavernous tissue by an immunohistochemical method. As a result, it was found that the lower penile VIP content was more frequent among patients with organic impotence than among the controls. Furthermore, VIP-ergic nerve fibers were seen to be diffusely and loosely distributed in a large number of organic impotence patients. These findings suggest that organic impotence in some patients may be due to decreases in the VIP content and in VIP-ergic nerve fibers.

Adolescent↗
PubMed1990

Comparative study on the innervation of nerves with calcitonin gene-related peptide, substance P and neurokinin A immunoreactivity in the walls of the cerebral arteries of small bats (Mammalia: Microchiroptera).

The distribution and origin of nerves with calcitonin gene-related peptide, substance P or neurokinin A immunoreactivity in the walls of the cerebral arteries were investigated in three microchiropteran species. The supply of nerves immunoreactive for substance P and neurokinin A to the bat cerebral arteries is confined mostly to the vertebral and basilar arteries. The density of innervation of calcitonin gene-related peptide-immunoreactive nerves and that of nerves with substance P or neurokinin A immunoreactivity in the vertebrobasilar system differ among species: the Japanese large footed bat is innervated with nerves with calcitonin gene-related peptide, substance P and neurokinin A immunoreactivity with about the same density, whereas in the greater horseshoe bat, there are many substance P-immunoreactive nerves with very weak or no calcitonin gene-related peptide immunoreactivity, and in the bent-winged bat, calcitonin gene-related peptide immunoreactivity is not found in all nerves with substance P immunoreactivity in the pial arteries of all parts of the brain. Nearly all cells immunoreactive for substance P, calcitonin gene-related peptide or both in the trigeminal and cervical dorsal root ganglia were small. In the greater horseshoe bat and the bent-winged bat, there is a correlation between the level of expression of substance P and calcitonin gene-related peptide immunoreactivity in the cervical dorsal root and trigeminal ganglia and the cerebral perivascular nerves supplying the vertebrobasilar system. The cerebrovascular innervation of nerves with substance P immunoreactivity in small bats is similar to that of cats and guinea-pigs in which the trigeminal ganglia have been destroyed. These observations, in addition to absence of nerve cells showing substance P or calcitonin gene-related peptide immunoreactivity in the pial artery and in the nerve bundles accompanying the extracranial internal carotid and vertebral arteries, suggest that substance P-immunoreactive nerves with or without immunoreactivity to calcitonin gene-related peptide in the vertebrobasilar system of small bats originate exclusively from the cervical dorsal root ganglia. The remaining fibres probably originate in the trigeminal ganglia.

Acetylcholinesterase↗
PubMed1990

Protein kinase C in Saccharomyces cerevisiae: comparison with the mammalian enzyme.

Protein kinase C (PKC) was detected in the yeast Saccharomyces cerevisiae with bovine myelin basic protein as the phosphate acceptor. The enzyme was purified at least 500-fold by a four-step column chromatographic procedure (phenyl-Sepharose CL-4B, Mono Q, Heparin-5PW, and hydroxyapatite). The molecular mass was approximately 90 kDa, as estimated by gel-filtration analysis. Yeast PKC was activated by the simultaneous addition of Ca2+, diacylglycerol, and phosphatidylserine. Free arachidonic acid alone could activate the enzyme to some extent. However, yeast PKC did not respond significantly to tumor-promoting phorbol esters. GTP did not serve as phosphate donor. The yeast enzyme showed substrate specificity distinctly different from that of mammalian PKCs. H1 histone and protamine were poor substrates. With myelin basic protein as a model substrate, yeast PKC phosphorylated threonyl residues preferentially, whereas rat brain PKCs phosphorylated seryl residues preferentially. Further studies should elucidate the role of yeast PKC in cellular regulation and cell cycle control.

Amino Acid Sequence↗
PubMed1990

Nonneoplastic and nonhyperplastic thymus in myasthenia gravis. An immunohistochemical study with double immunoenzymatic labeling of basement membrane and cellular components.

Histologically normal thymus (type A) in patients with myasthenia gravis (MG) was immunohistochemically compared with hyperplastic MG thymus (type B) and normal non-MG thymus. In formalin-fixed, paraffin-embedded sections of ten type A, ten type B, and eight non-MG cases, the thymic epithelium and other cellular components were stained in conjunction with the basement membrane by a double immunoenzymatic method. This technique demonstrated a moderate architectural disturbance in type A thymus, with distended perivascular space (PVS), elongated medullary epithelium, and disrupted basement membrane. These changes were more prominent in type B thymus but were minimal to lacking in non-MG thymus. Compared with those in non-MG thymus, the myoid cells in MG thymuses of both types tended to cluster around the Hassall's corpuscles, with a slight decrease in number in type B but not in type A. B-lymphocytes were present in type B, type A, and non-MG thymuses in that order of abundance; the cells were confined to the medullary parenchyma in the non-MG group but were numerous both in the PVS and medulla in the MG groups. T-lymphocytes were increased in the expanded PVS of type A and B MG thymuses. The number of interdigitating reticulum cells was similar in the three groups, but the cellular distribution was more dispersed in MG thymuses of both types. These findings, although previously described in type B thymus, have not been well recognized in type A thymus. They support the view that a common abnormality (presumably chronic thymitis), differing in degree only, underlies MG thymuses regardless of the presence of follicular hyperplasia.

Adolescent↗
PubMed1990

The role of the left ventricle in atrial natriuretic peptide secretion in acute mitral regurgitation.

To examine the role of the ventricle in ANP secretion, the atrial natriuretic peptide (ANP) concentration in the plasma, left atrial tissue and left ventricular tissue were observed in a canine during the course of experimental reversible mitral regurgitation (MR). For reversible MR, a basket catheter was inserted into the left atrium via the pulmonary vein and fixed at the mitral valve. The regurgitation arose when the tip basket wire was extended and disappeared immediately when it was closed. Left atrial pressure (LAP), right atrial pressure (RAP) and pulmonary artery pressure (PAP) increased significantly during MR, and decreased to the normal level after recovery from MR. Plasma ANP concentration showed a reversible change in correlation with LAP and RAP in each canine studied. The ANP level in the atrial and ventricular tissue decreased during MR, and the low levels were maintained after recovery from MR. Both the left arterial and left ventricular tissue ANP levels showed the same changes in acute MR. Therefore, it was suggested that normal ventricles might play a role in ANP secretion in acute MR.

Animals↗
PubMed1990

Etoposide protects mice from radiation-induced bone marrow death.

Etoposide is known to inhibit the activity of topoisomerase II, and to possess radiosensitizing effects. In this paper we show that pretreatment of mice with etoposide one day before whole-body irradiation had a protective effect against radiation-induced bone marrow death. The LD50/30 of mice given radiation alone was 8.26 Gy while that of mice given etoposide one day before whole-body irradiation was 10.35 Gy. The number of endogenous colony-forming units surviving in whole body-irradiated mice was significantly increased by pretreatment with etoposide.

Animals↗
PubMed1990

Magnesium concentration in brains from multiple sclerosis patients.

Magnesium (Mg) concentrations were studied in the brains of 4 patients with definite multiple sclerosis (MS) and 5 controls. The magnesium contents were determined by inductively coupled plasma emission spectrometry in autopsy samples taken from 26 sites of central nervous system tissues, and visceral organs such as liver, spleen, kidney, heart and lung. The average Mg content in the CNS tissues, as well as visceral organs except for spleen, of MS patients showed a significantly lower value than that seen in control cases. The most marked reduction of Mg content was observed in CNS white matter including demyelinated plaques of MS samples. Whether or not these significantly lower Mg contents found in CNS and visceral organs of MS patients may play an essential role in the demyelinating process remain unclear, requiring further studies on MS pathogenesis from the point of metal metabolism.

Adult↗
PubMed1990

The physiological and biological significances of human atrial natriuretic peptide in neonates.

The purpose of our study was to analyze the physiological and biological significances of the high human atrial natriuretic peptide (hANP) levels during early post-natal period. The absolute values or changes of plasma hANP concentrations did not correlate with the absolute values or changes of body weight, blood pressure, urinary sodium/creatinine and urinary aldosterone/creatinine ratios. Gel permeation chromatography of samples from two neonates revealed the presence of two molecular forms of hANP, alpha and beta, both in the plasma and urine. In the plasma, the beta-hANP was predominant on the 3rd day of life and the alpha-hANP on the 6th day of life. The change from one form to another was independent of the absolute value of hANP. We obtained no evidence suggestive of a physiological role of the high plasma hANP concentration during the early post-natal period. However, because of biological differences between these two fractions, their distribution must be taken into account when attempting to interpret the high hANP values observed in neonates.

Atrial Natriuretic Factor↗
PubMed1990

A novel Bacillus subtilis gene involved in negative control of sporulation and degradative-enzyme production.

We have cloned a 2.5-kilobase fragment of the Bacillus subtilis genomic DNA which caused the reduction of extracellular and cell-associated protease levels when present in high copy number. This fragment, in multicopy, was also responsible for reduced levels of alpha-amylase, levansucrase, alkaline phosphatase, and sporulation inhibition. The gene relevant to this pleiotropic phenotype is referred to as pai. By DNA sequencing, two open reading frames--ORF1 and ORF2, encoding polypeptides of 172 and 207 amino acid residues, respectively--were found. These open reading frames seemed to form an operon. Deletion analysis revealed that an entire region for ORF1 and ORF2 was necessary for the pai phenotype. In addition, it was observed that the presence of the pai gene, in multicopy, caused overproduction of two proteins (molecular masses, 21 and 24 kilodaltons [kDa]). Analyses of the N-terminal amino acid sequences of these two proteins suggested that they were products of ORF1 and ORF2. Disruption of the pai gene at ORF1 in the genomic DNA resulted in the release of repression on protease synthesis and sporulation in glucose-enriched (2%) medium. The mutant carrying insertional disruption at ORF2 could not be constructed, suggesting that the ORF2 product, the 24-kDa protein, is essential for growth. The 21-kDa protein contains a helix-turn-helix domain observed in other DNA-binding proteins. Chromosomal mapping of pai indicated that this gene is located close to thr-5. These results suggest that the pai gene is a novel transcriptional-regulation gene involved in glucose repression.

Alkaline Phosphatase↗
PubMed1990

Hemodynamic effects of calcitonin gene-related peptide in spontaneously hypertensive rats.

Systemic and regional hemodynamic effects of intravenously injected calcitonin gene-related peptide (CGRP), 220 and 650 pmol, were compared in nine Wistar-Kyoto (WKY) and nine spontaneously hypertensive rats (SHR). CGRP (higher dose) reduced mean arterial pressure (from 135 +/- 2 to 83 +/- 2 and from 179 +/- 4 to 116 +/- 3 mmHg; P less than 0.01, each, in WKY and SHR, respectively) through a fall (-38 +/- 4 and -40 +/- 3%; P less than 0.01) in total peripheral resistance associated with an unchanged cardiac output and an increased heart rate. The decreases in arterial pressure and total peripheral resistance were not different between these two strains. Of particular significance were the highly selective reductions in organ vascular resistances, being greatest in the cutaneous (-78 +/- 3 and -67 +/- 4%) and gastric (-80 +/- 3 and -84 +/- 2%) circulations in WKY and SHR, respectively (P less than 0.01). Reduction in coronary, cerebral, and hepatic vascular resistances, although significant (P less than 0.05, at least), were only moderately reduced compared with the two former circulations. These effects were similar in WKY and SHR and demonstrate that CGRP is a highly selective and potent natural vasodilating peptide that has the most striking effects in skin and stomach, suggesting possible modulator functions in regulating certain regional hemodynamics.

Animals↗