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Biomedical subjects

M Yoshida

Publications and source records attributed to M Yoshida.

At least 1,261 records · Page 70Linked to original sources
PubMed1995

Detection of Y-bearing porcine spermatozoa by in situ hybridization using digoxigenin-labeled, porcine male-specific DNA probe produced by polymerase chain reaction.

This study was carried out to determine whether Y-bearing porcine spermatozoa could be detected by in situ hybridization using a digoxigenin (Dig)-labelled DNA probe specific to the Y chromosome produced by polymerase chain reaction (PCR). A conventional PCR (with Dig-dUTP) was performed using a set of oligonucleotide primers (5'-AAGTGGTCAGCGTGTCCATA-3' and 5'-TTTCTCCTGTATCCTCCTGC-3') for 236 bp fragment of porcine male-specific DNA sequence and 1.25 x 10(4) template white blood cells obtained from a boar. When fluorescence in situ hybridization with the Dig-labelled DNA probe was applied to the metaphase chromosome spreads prepared from both boar and gilts, the fluorescein signal was only detected on the long arm of the Y chromosome. In addition, immunocytochemical detection with the Dig-labelled DNA probe and alkaline phosphatase-labeled anti-Dig was applied to both sperm nuclei pretreated with dithiothreitol and white blood cells; 51% of sperm nuclei and 96% of white blood cells obtained from boar were labelled, whereas none of white blood cells obtained from gilts were labelled with the Dig-labelled DNA probe. The results indicated that in situ hybridization with porcine male-specific DNA probe produced by PCR made possible the direct visualization of Y-bearing porcine spermatozoa by in situ hybridization.

Animals↗
PubMed1995

Detection of gamma-aminobutyric acid in a living rat brain using in vivo microdialysis-capillary electrophoresis/mass spectrometry.

Coupling of in vivo microdialysis with capillary electrophoresis/mass spectrometry (MD-CE/MS) was demonstrated. A microdialysis probe was inserted in the striatum of a rat brain and gamma-aminobutyric acid (GABA) in the brain was detected by CE/MS without any chemical treatment of the sample. MD-CE/MS is expected to be a useful technique for analyzing brain substances, because of the relatively small damage it causes to a living structure and the high selectivity of the analytical technique.

Animals↗
PubMed1995

Significance of altered fluidity of plasma membranes of the liver and kidney in rats with sepsis.

The present study was conducted to investigate changes in plasma membrane fluidity of the liver and kidney in sepsis, which is the main cause of multiple organ failure. Male Wistar rats weighing 200-250 g were used in all experiments. Sepsis was induced by cecal ligation and puncture. As a control, a sham operation was performed. The time course of plasma membrane fluidity of the liver and the renal cortex in septicemic rats or in controls was studied. To evaluate the fluidity, fluorescence polarization was measured using 1,6-diphenyl-1,3,5-hexatriene. The fluorescence polarization values of liver plasma membranes increased after cecal ligation and puncture: 0.183 +/- 0.004 (mean +/- SEM), 0.194 +/- 0.008, 0.206 +/- 0.003, and 0.210 +/- 0.002 at 0, 24, 48, and 72 hr, respectively. Corresponding values for membranes of the renal cortex increased in a similar fashion. To determine whether factors involved in cell membrane damage exist in blood, the direct effects of lipopolysaccharide (LPS), platelet-activating factor (PAF), and serum from normal rats or from septicemic rats on membrane fluidity were studied. The fluorescence polarization of plasma membranes of the liver or renal cortex to which septicemic rat serum was added was higher than that of plasma membranes to which normal rat serum was added. The fluorescence polarization of liver plasma membranes was increased by LPS, but that of plasma membranes of the renal cortex was slightly decreased. In addition, the fluorescence polarization of liver plasma membranes was increased by PAF, but that of plasma membranes of the renal cortex was decreased.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1995

Alterations in multiple tyrosine hydroxylase mRNAs in the substantia nigra, locus coeruleus and adrenal gland of MPTP-treated parkinsonian monkeys.

Monkeys are known to be highly susceptible to 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) which produces parkinsonism, as in humans. We have previously reported that only monkeys and humans have multiple isoforms of tyrosine hydroxylase (TH), the first enzyme for dopamine biosynthesis, with only two TH mRNA isoforms, type 1 and type 2, being present in Macaca fascicularis. In the present study we have measured TH mRNA type 1 and 2 content in the substantia nigra, locus coeruleus, and adrenal gland of normal control monkeys and in MPTP-produced parkinsonian monkeys (Macaca fascicularis) using a newly developed, sensitive and quantitative assay based on the reverse transcription-polymerase chain reaction. Marked decreases in TH mRNA type 1 and 2 content were observed, specifically in the substantia nigra of the monkeys with MPTP-parkinsonism compared to control monkeys. These results are similar to our recent data showing marked decreases in TH mRNA type 1, 2, 3 and 4 content in the substantia nigra of patients with Parkinson's disease, and suggest that MPTP-treated monkeys closely replicate changes in TH isoforms in human Parkinson's disease.

1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine↗
PubMed1995

Arachidonic acid metabolites and glucocorticoid regulatory mechanism in cultured porcine tracheal smooth muscle cells.

To elucidate the signal transduction system in the production of prostaglandin E2 (PGE2) by porcine tracheal smooth muscle cells in culture (PTSMC), we examined the pattern of arachidonic acid metabolites released from PTSMC and the relationship between bradykinin-stimulated rises in intracellular calcium concentration ([Ca2+]i) and PGE2 production by PTSMC. We next examined the effect of dexamethasone on these parameters. Bradykinin induced a dose-dependent increase in both the rise in [Ca2+]i and PGE2 production by PTSMC. The increase in [Ca2+]i paralleled an increase in PGE2 production. High-performance liquid chromatography (HPLC) revealed that dexamethasone-treated PTSMC were suppressed to release arachidonic acid metabolites such as PGE2 and prostaglandin F2 alpha (PGF2 alpha). Incubation of PTSMC with 10(-6)M dexamethasone for 24 h significantly suppressed both the rise in [Ca2+]i and PGE2 production by PTSMC in response to bradykinin, and also significantly suppressed bradykinin-stimulated release of radioactivity from PTSMC prelabeled with 3H-labeled arachidonic acid (3H-AA). When PTSMC pretreated with dexamethasone were incubated with 170 nM prostaglandin H2 (PGH2) or 20 microM arachidonic acid; PTSMC synthesized less PGE2 than control PTSMC. Results suggest that bradykinin stimulates PTSMC to produce PGE2 via the signal transduction system including Ca2+, and dexamethasone appeared to suppress PGE2 production by reducing the activity of cytosolic phospholipase A2 (cPLA2) and PGE2 synthase. However, we failed to demonstrate the suppression of the activity of cyclooxygenase in PTSMC by dexamethasone. Since the elevation of [Ca2+]i is necessary for the contraction of airway smooth muscles, dexamethasone seems to reduce the contraction of airway smooth muscles by suppressing the rise in [Ca2+]i and the release of arachidonic acid metabolites. Reduced production of arachidonic acid metabolites may also contribute to improvement in the bronchial inflammation.

Animals↗
PubMed1995

Correlation of p53 protein expression with apoptotic incidence in colorectal neoplasia.

The wild-type p53 gene suppresses cell proliferation and induces apoptosis when it is transfected into human colon cancer cell lines. Therefore, mutation of the p53 gene, which correlates closely with p53 protein overexpression, would be predicted to activate cell proliferation and limit apoptosis. We tested this hypothesis by correlating p53 protein expression with cell proliferation and apoptosis in 70 neoplasms (29 adenomas and 41 carcinomas) using p53 and Ki-67 immunohistochemical staining and DNA nick end labelling. The p53 immunoreactivity was independent of the Ki-67 positivity. The apoptotic incidence was less frequent (P < 0.005) in tumours with diffuse p53 protein overexpression than in those with the sporadic overexpression, defined as p53 staining of isolated or scattered expression. In addition, apoptotic incidence only correlated directly (P < 0.05) with Ki-67 positivity in tumours with sporadic p53-protein expression. These results indicate that p53 protein that is expressed sporadically in colorectal neoplasms is probably wild-type protein and induces apoptosis in response to active cell proliferation. In contrast, diffusely overexpressed p53 protein in colorectal neoplasms is probably mutant and correlates with a reduction in apoptotic cell death independently of cell proliferation.

Adenoma↗
PubMed1995

Portal and peripheral endotoxins in patients with esophageal varices undergoing surgery.

Under the hypothesis that portal endotoxemia, which has been considered evidence of endogenous endotoxemia, is actually a false-positive reaction of the Limulus test, the conventional method of determination, Toxicolor (TOX) and a new endotoxin-specific method, Endospecy (ES) were investigated, whereby portal endotoxemia was reexamined. Peripheral and portal blood samples were collected from 12 patients at various intervals during surgery for esophageal varices, and then evaluated by TOX and ES, the normal values of which are under 60.0 pg/ml and under 9.8 pg/ml, respectively. The mean peripheral and portal endotoxin (Et) levels by TOX were 23.1 pg/ml and 38.9 pg/ml, 1.5 h after the start of surgery, which continued to increase thereafter, the corresponding levels being 48.1 pg/ml and 58.7 pg/ml 8 h after the start of surgery, respectively. The portal Et levels were significantly higher by ES, indicating portal endotoxemia, the mean peripheral and portal Et levels being 6.9 pg/ml, and 6.5 pg/ml, 1.5 h after the start of surgery, these levels showing changes within a similar range. The levels determined by the conventional TOX method increased with time, to a portal Et level of 5.0 pg/ml 8 h after the start of surgery, whereas those determined by ES changed within the same range suggesting that the onset of portal endotoxemia primarily involves the G-factors and that endogenous endotoxemia does not occur.

Blood Specimen Collection↗
PubMed1995

Lesser sac herniation through the greater omentum and gastro-pancreatic ligament: report of a case.

We report herein the case of a woman who developed a lesser sac hernia which was especially unusual in that the small bowel prolapsed through a defect in the greater omentum and was thereafter strangulated by a hole in the gastro-pancreatic ligament. The gastro-pancreatic ligament has never before been documented as causing an internal hernia. In our patient, a plain abdominal X-ray demonstrated as soft-tissue mass displacing the stomach to the left while abdominal computed tomography and ultrasonography showed a sac-like encapsulation of the small bowel loops between the liver and stomach. Careful evaluation of these radiographic findings allowed for the preoperative diagnosis of a lesser sac hernia to be made.

Adult↗
PubMed1995

Alteration in the fluorescence polarization of rat plasma and liver cell membranes following bile duct ligation in rats.

The fluorescence polarization levels of liver cell membranes and plasma were analyzed to determine membrane fluidity following bile duct ligation (BDL) in rats. Fluorescence polarization was measured with a spectrofluorophotometer equipped with polarizers, using 1,6-diphenyl-1,3,5-hexatrien (DPH) as a probe. After bile duct ligation, liver cell membrane fluidity decreased significantly for up to 14 days after surgery (P < 0.001 on 3rd and 7th days). The polarization of the plasma in rats with BDL slightly but significantly increased compared to the levels in the control animals over the 14-day period following BDL. In addition, a small but significant correlation in the polarization levels between plasma and liver cell membranes (r = 0.362, P < 0.02) was observed. The co-incubation of BDL plasma with normal liver cell membranes resulted in a decrease in membrane fluidity, which suggested that BDL rat plasma had a direct effect on membrane fluidity. After a 70% hepatectomy, the polarization of the membranes from remnant livers in the BDL rats remained elevated relative to the sham-operated controls. It is thus concluded that the membrane fluidity of the livers in BDL rats decreases following bile duct ligation and does not increase after a 70% hepatectomy, presumably due to the increased plasma level of bilirubin.

Animals↗
PubMed1995

Acute left atrial thrombus causing cardiogenic shock following mitral valve replacement: report of a case.

We report herein the rare case of a 53-year-old woman who developed cardiogenic shock due to an acute left atrial thrombus following replacement of the mitral valve. A definitive diagnosis was not able to be made using precordial echocardiography because of the broad, flat shape of the thrombus; however, transesophageal echocardiography imaged the thrombus in detail. The patient was initially stabilized by percutaneous cardiopulmonary support after which a thrombectomy was successfully performed.

Echocardiography, Transesophageal↗
PubMed1995

Malposition of a totally implantable venous access catheter in the azygous vein: report of a case.

We report herein the case of a 2-year-old girl with short bowel syndrome who developed chest pain 2 weeks after a totally implantable central venous access catheter had been surgically placed to facilitate total parenteral nutrition. A lateral chest X-ray and contrast flow study subsequently revealed that the catheter tip had been inserted into the azygous vein. Although this complication is very rare, it may be encountered more commonly with the increasing use of this type of venous access. Thus, we believe that a lateral chest X-ray should be routinely performed on all patients following catheter insertion to check for possible malposition of the tip in the azygous vein.

Catheters, Indwelling↗
PubMed1995

Carcinoma of the reconstructed stomach tube following esophageal resection for a benign stricture: report of a case and review of the literature.

We report herein the case of a 60-year-old woman who presented with dysphagia and anorexia and was subsequently diagnosed as having gastric cancer of the reconstructed stomach tube 36 years after undergoing surgery for a benign esophageal stricture. Reports on carcinoma of the reconstructed stomach tube are rarely found and interestingly, all of the previous cases, which were documented only in the Japanese literature, corresponded to metachronous double cancers after esophageal malignancies. To our knowledge, this is the first case of carcinoma of the reconstructed stomach tube following esophageal resection for a benign stricture, and it is thought that the carcinoma probably developed at the site of the anastomosis a long time after the first operation. We reviewed 30 cases of carcinoma of the reconstructed stomach tube for which the clinicopathological data was complete, and we believe that this new type of cancer needs more than 10 years to develop and should be defined as "carcinoma of the gastric remnant".

Adenocarcinoma↗
PubMed1995

Comparative pharmacodynamic analysis of TAT-59 and tamoxifen in rats bearing DMBA-induced mammary carcinoma.

TAT-59 suppressed the growth of DMBA-induced mammary tumors in rats earlier and more strongly than tamoxifen (TAM). After oral administration of the drugs, DP-TAT-59, one of the main metabolites of TAT-59, was found in 10- to 15-fold higher concentrations in both the tumor and blood compared to 4-OH-TAM, an active metabolite of TAM. In a 3-day antiuterotrophic test, every detected metabolite of TAT-59 showed stronger antiestrogenic activity than did TAM. In a competition assay, the affinity of the metabolites for estrogen receptors ranged from that of estradiol to that of TAM. These results suggest that the superior antiestrogenic activity of TAT-59 compared to TAM was either due to its higher penetration into tumor tissue or to the stronger antiestrogenic activity of its metabolites.

9,10-Dimethyl-1,2-benzanthracene↗
PubMed1995

HTLV-1 oncoprotein Tax deregulates transcription of cellular genes through multiple mechanisms.

Infection of a human retrovirus HTLV-1 induces adult T cell leukemia and a neurological disease, HAM/TSP. Regulatory protein Tax of HTLV-1 is thought to contribute to the pathogenesis. We have studied the mechanism of transcriptional activation induced by Tax protein and identified two independent mechanisms: (a) binding to the enhancer-binding proteins, CREB, CREM, NF-kappa B and SRF, resulting in the activation of these factors through indirect binding to each specific DNA sequence, and (b) binding to I kappa B protein resulting in the suppression of the negative regulator I kappa B, which binds to NF-kappa B. In addition to these factors, a new protein GLI/THP is also involved in the transactivation. On the basis of these mechanisms, gene regulations in vitro and in vivo in HTLV-1-infected cells are discussed.

Base Sequence↗
PubMed1995

Detection of green algae (Chlorophyceae) for the diagnosis of drowning.

The plankton test (generally, diatom test) is one of the methods available to diagnose the cause of death of submerged bodies. The solubilization method using tissue solubilizer Soluene-350 was used in this study to detect not only diatoms but also green algae, based on the fact that the solubilizer does not digest the cell walls of green algae which are made from cellulose. Detection of green algae from organs of submerged cadavers is very informative to determine drowning in fresh water, and also in cases where only few diatoms are detected in the organs.

Acetone↗