Search PubMed⌕ Search

Biomedical subjects

S Yoshida

Publications and source records attributed to S Yoshida.

At least 379 records · Page 21Linked to original sources
PubMed2000

Tumor necrosis factor-alpha promotes proliferation of endometriotic stromal cells by inducing interleukin-8 gene and protein expression.

Endometriosis, a common disease among women of reproductive age, is characterized by the presence of endometrial-like tissue outside the uterus. We and others showed that several cytokine levels, including interleukin-8 (IL-8) and tumor necrosis factor-alpha (TNFalpha), are elevated in the peritoneal fluid of women with endometriosis compared with those in women without endometriosis. We also demonstrated that the addition of IL-8 to the culture medium stimulated the proliferation of cultured endometriotic stromal cells. TNFalpha is a multipotent cytokine that induces IL-8 production in various cell types. Therefore, we hypothesized that TNFalpha may also contribute to the pathogenesis of endometriosis by inducing the production of IL-8. To test this hypothesis, we analyzed the peritoneal fluid concentrations of IL-8 and TNFalpha using enzyme-linked immunosorbent assay (ELISA). We observed a significant correlation between the levels of TNFalpha and IL-8 in the peritoneal fluid of endometriosis patients. We also obtained the endometriotic stromal cells from chocolate cyst linings of the ovary. The expression of the receptors for TNFalpha (TNFR) was examined by RT-PCR. We observed the expression of both TNFR-I and TNFR-II genes in endometriotic stromal cells. The expression of IL-8 gene and protein was analyzed by Northern blot hybridization and enzyme-linked immunosorbent assay, respectively. TNFalpha induced the gene and protein expression of IL-8 in endometriotic stromal cells in a dose-dependent fashion. The addition of TNFalpha promoted the proliferation of the endometriotic stromal cells, and the stimulatory effects of TNFalpha were abolished by adding anti-IL-8 antibody. We demonstrated for the first time that TNFalpha stimulated proliferation of endometriotic stromal cells through induction of IL-8 gene and protein expression. We concluded that the TNFalpha may be one of the essential factors for the pathogenesis of endometriosis.

Adult↗
PubMed2000

Non-glutamate type pyrrolo[2,3-d]pyrimidine antifolates. III. Synthesis and biological properties of N(omega)-masked ornithine analogs.

The glutamic acid moiety of N-[4-[3-(2,4-diamino-7H-pyrrolo[2,3-d]pyrimidin-5-yl)propyl]benzoyl]-L-g lutamic acid (1b, TNP-351) and the related compound (1a), was replaced with various N(omega)-acyl-, sulfonyl-, carbamoyl- and aryl-2,omega-diaminoalkanoic acids, and the inhibitory effects of the resulting products (9, 11, 14, 18, 21, 23, 25, 30, 36) on dihydrofolate reductase (DHFR), the growth of murine fibrosarcoma Meth A cells, and methotrexate-resistant human CCRF-CEM cells, were examined. Compounds (9a-f) acylated with a hemiphthaloyl group were efficiently synthesized by coupling pyrrolo[2,3-d]pyrimidine carboxylic acids (7a,b) and N(omega)-phthaloyl 2,omega-diaminoalkanoic acid methyl esters (6a-c) and subsequent hydrolysis. The other N(omega)-acyl- and sulfonyl-ornithine analogs (21, 23, 25) were synthesized by acylation of free amino intermediates (19a,b) derived from tert-butoxycarbonyl-ornithine analogs (17a,b). A free ornithine analog (18) did not strongly inhibit Meth A cell growth, whereas all N(omega)-acyl-, sulfonyl-, carbamoyl- and aryl-ornithine analogs (9, 11, 21, 23, 25, 30, 36) exhibited much more potent inhibitory activities against both DHFR and Meth A cell growth. In particular, compounds 9c, 21k and 36a also showed remarkable growth-inhibitory activities against methotrexate-resistant CCRF-CEM cells. These results demonstrate that the potent inhibitory activities of N(omega)-masked ornithine analogs against the growth of Meth A cells and methotrexate-resistant CCRF-CEM cells, results from effective uptake via reduced folate carrier and their potent DHFR inhibition.

Cell Division↗
PubMed2000

Transient complete atrioventricular block during catheter ablation of left free wall bypass tract.

Radiofrequency catheter ablation of accessory bypass tracts associated with the Wolff-Parkinson-White (WPW) syndrome has become an accepted and widespread therapy. When bypass tracts are located in the free wall of the left ventricle, complete atrioventricular (AV) block is an unusual complication. Two cases of symptomatic WPW syndrome with transient complete atrioventricular block during catheter ablation are described. The first case was a 14-year-old female with an accessory pathway located in the left posterior wall, and the second was a 72-year-old female with an accessory pathway located in the left lateral wall. Radiofrequency energy application resulted in transient complete AV block with escape rhythm. In the first case, AV conduction with left bundle branch block resumed the next day, whereas in the second case, AV conduction soon resumed with prolongation of atrio-His (AH) interval and no evidence of pre-excitation. This phenomenon could have been due to either trauma to the AV node during catheter entry into the left ventricle or compression of the AV node with a catheter shaft during ablation because both patients' hearts were comparatively small.

Adolescent↗
PubMed2000

Determination of major and trace elements in the liver of Wistar rats by inductively coupled plasma-atomic emission spectrometry and mass spectrometry.

Inductively coupled plasma-mass spectrometry (ICP-MS) and inductively coupled plasma-atomic emission spectrometry (ICP-AES) were used to determine age-related changes in the concentrations of constituent elements in the livers of Wistar rats of 1 week to 12 months old. At first, sample preparation and analytical conditions were investigated in order to set up a simple routine procedure for measuring multiple elements simultaneously. Seventeen elements in the standard reference samples of bovine and pork livers as well as rat liver samples could be determined with a reasonable precision and reproducibility. They were P, K, Na, Fe, Mg, Ca, Zn, Rb, Cu, Mn, Mo, Al, Co, Sr, Cs, Pb, and Cd in order of the levels of concentration in the adult rat livers. Of these elements, the five major elements (P, K, Na, Fe, Mg, Ca) were determined with ICP-AES and the others with ICP-MS. Although the number of animals was too small to draw a statistically definite conclusion, it seems that age-related changes in the concentrations of these elements could be categorized into three general patterns: (1) remaining essentially constant throughout the animal ages, as observed for P, K, Na, Mg, Ca, Rb, Sr, Cs, and Pb, (2) increasing with age, as observed for Fe, Mn, Mo, Co, and Cd, and (3) decreasing with age, especially in the early stages of growth, as observed for Cu and Zn.

Age Factors↗
PubMed2000

Acquired anomalous intrapulmonary venous connection secondary to pulmonary venous stenosis.

An unusual case of acquired development of anomalous intrapulmonary venous connection with pulmonary venous stenosis is presented. Appearances on a chest radiograph resembled the "scimitar" sign in a patient with previous surgery for partial anomalous pulmonary venous return. Spiral CT and pulmonary arteriography showed stenosis of the right upper pulmonary vein and an anomalous intrapulmonary venous connection between the right upper pulmonary vein and the right lower pulmonary vein. We consider the slow progression of pulmonary vein stenosis led to anomalous intrapulmonary venous connection as an intrapulmonary collateral.

Adult↗
PubMed2000

Application of the random arbitrary primed polymerase chain reaction differential display method to isolate genes of cholesterol metabolism-related proteins from rat liver.

The random arbitrary primed (RAP) polymerase chain reaction (PCR) differential display (DD) method was applied to isolate genes related to cholesterol metabolism from exogenously hypercholesterolemic (ExHC) rats and the progenitor, SD rats. Forty-seven trials of RAP-PCR DD resulted in the isolation of 37 clones differing in strain, cholesterol supplementation or their interaction. Among their fingerprints, five clones gave reproducible patterns by a Northern blotting analysis. The sequence of two clones with lower mRNA abundance in ExHC rats than in SD rats was homologous to that of fatty acid synthase and oxalyl-CoA decarboxylase. Two other clones with higher mRNA on the n-cholesterol diet were matrin F/G protein and the NMDA receptor glutamate-binding subunit. The other clone with higher mRNA abundance in ExHC rats on the cholesterol diet was myelodysplasia/myeloid leukemia factor 2. Fifteen trials of reverse transcriptase (RT)-PCR DD yielded 10 clones, but none of the fingerprints were reproduced by the Northern blotting analysis. These results indicate that RAP-PCR DD is an appropriate alternative to RT-PCR DD for isolating the genes involved in hypercholesterolemia.

Animals↗
PubMed2000

Superiority of dietary safflower oil over olive oil in lowering serum cholesterol and increasing hepatic mRnas for the LDL receptor and cholesterol 7alpha-hydroxylase in exogenously hypercholesterolemic (exHC) rats.

The exogenously hypercholesterolemic (ExHC) rat is a strain segregated from SD rats with a high response to dietary cholesterol. To understand the underlying mechanism(s) for this hypercholesterolemia, the interactive effects of dietary fatty acid and the susceptibility of rats to dietary cholesterol on the serum cholesterol concentration and hepatic mRNA abundance of the low-density lipoprotein (LDL) receptor, cholesterol 7alpha-hydroxylase (7alpha-hydroxylase) and 3-hydroxyl-3methylglutaryl (HMG) CoA reductase were examined. Both strains were fed on a diet supplemented with 10% each of olive, safflower or coconut oil with or without the addition of 1% cholesterol for one week. The ExHC rats fed on olive, safflower and coconut oil in combination with cholesterol respectively resulted in a 3.5-, 2.0- and 2.1-fold higher serum cholesterol concentration than that in the animals fed on the corresponding dietary fats without any supplementation of cholesterol (p < 0.01 by dietary cholesterol or type of fat). The dietary cholesterol dependent-elevation of serum cholesterol in the SD rats was less than 1.5-fold (p<0.01) and there was no dietary fat effect. The ExHC rats fed on the safflower oil-containing diet supplemented with cholesterol resulted in a higher mRNA abundance of the LDL receptor and 7alpha-hydroxylase than in the corresponding fat-fed rats without cholesterol (p<0.05). There was no dietary cholesterol-dependent change of mRNA abundance in either strain fed on olive or coconut oil, except for a decreased abundance of HMG CoA reductase mRNA in the olive oil-fed ExHC rats and coconut oil-fed Sprague-Dawley (SD) rats (p<0.05). These results indicate that the hepatic mRNA abundance of the LDL receptor and of 7alpha-hydroxylase depended on the dietary combination of cholesterol and a fatty acid and suggest that a linoleic acid-rich diet may alleviate exogenous hypercholesterolemia by activating the process involved in the hepatic uptake and biliary excretion of serum cholesterol.

Animals↗
PubMed2000

Coronary artery bypass grafting in the elderly.

BACKGROUND AND METHODS: The incidence of coronary artery bypass grafting (CABG) in elderly patients has been increasing. We retrospectively analyzed the results of CABG performed at Shin-Tokyo Hospital between January 1, 1991, and December 31, 1998. Preoperative, perioperative, and follow-up data of patients > or = 75 years old (group E, n = 190) were collected, and compared with those of patients < 75 years old (group Y, n = 1,380). RESULTS: Female gender, emergent CABG, preoperative balloon pumping use, cardiogenic shock, hypertension, and preoperative cerebral vascular accident were significantly more frequent in group E (p < 0.05). CABG was completed without any significant differences, except for less frequent use of the bilateral internal mammary artery (p < 0.01), more frequent use of the saphenous vein (p < 0.005), and a greater incidence of blood transfusion in group E (p < 0.0001). The postoperative course required longer intubation, ICU stay, and postoperative hospital stay in group E (p < 0.001), and was more frequently associated with major complication (p < 0.0001) and in-hospital death (p < 0.05). During the mean follow-up of 2.7 years (maximum 6.9 years), the actuarial 5-year survival of groups E and Y were 84.3% and 92.5% (p < 0.01), respectively, excluding in-hospital mortality. The actuarial 5-year cardiac event-free rates were 79.9% in group E and 79.7% in group Y, showing no significant difference. CONCLUSIONS: CABG in the elderly carries certain surgical risks. However, the long-term cardiac event-free rate after CABG in the elderly was almost the same as that of younger patients. Inferior long-term survival in the elderly was most likely due to the biological nature of aging.

Aged↗
PubMed2000

A clinical feature of hyperlipidemia in patients with central diabetes insipidus.

In this study, we analyzed plasma lipid and lipoprotein levels before and after treatment with 1-desamino-8-D-arginine vasopressin (DDAVP) in subjects with partial and complete central diabetes insipidus (DI) in order to determine how a shortage and supplement of this hormone affect plasma lipid metabolism. The subjects consisted of 6 patients with partial and 6 with complete central DI. After treatment with DDAVP through nasal cavity, plasma total cholesterol (TC) level did not decrease either in complete or partial form. Plasma triglyceride (TG) levels decreased from 306+/-175 mg/dl to 198+/-91 (35% decrease, p=0.027) in complete form, while TG did not change significantly in partial form. A detailed investigation of plasma lipoprotein metabolism during treatment with DDAVP was carried out in 3 of the 6 subjects with complete form of DI. Lipoprotein lipase activity and mass in post-heparin plasma from those three subjects tended to increase after treatment with DDAVP, along with the complete disappearance of an unusual lipoprotein between low density lipoprotein (LDL) and very low density lipoprotein (VLDL) as analyzed by polyacrylamide gel electrophoresis. These results suggest that the DDAVP treatment has a favorable effect on lipid and lipoprotein metabolism, especially triglyceride-rich lipoproteins, either directly or through modifying factors contributing to lipid metabolism.

Administration, Intranasal↗
PubMed2000

Isolation and initial characterization of 13(2)-hydroxychlorophyll a induced by cyclohexanedione derivatives in tobacco cell suspension cultures.

This paper reports that a new photobleaching compound, 2-(2-chloro-5-propoxycarbonylphenyl)aminomethylidene-5-5-dim ethyl- cyclohexane-1,3-dione (RWH-21), stimulates accumulation of 13(2)-hydroxychlorophyll a in cultured tobacco cells. This was shown based on isolation of 13(2)-hydroxychlorophyll a from pigment extracts of cultured tobacco cells by diode-array HPLC and subsequent fast atom bombardment mass spectrometry analysis. 13(2)-Hydroxychlorophyll a rapidly accumulates in tobacco cells both in the light and dark in the presence of RWH-21 (50 microM). Analysis of 13(2)-hydroxychlorophyll a formation in tobacco cells indicates that 13(2)-hydroxychlorophyll a is rapidly accumulated within 20 h incubation time both in the dark and light. Although the amount of 13(2)-hydroxychlorophyll a is continuously increased in the dark, the amount of 13(2)-hydroxychlorophyll a decreased remarkably in the light after 20 h incubation. Analysis of 13(2)-hydroxychlorophyll a formation and lipid peroxidation by determination malondialdehyde in tobacco cells suggests that RWH-21-induced 13(2)-hydroxychlorophyll a has the potential to cause a photodynamic action in cultured tobacco cells.

Cells, Cultured↗
PubMed2000

Analysis of scar tissue distribution on rat palates: a laser Doppler flowmetric study.

OBJECTIVE: The aim of this study was to evaluate the effectiveness of laser Doppler flowmetry (LDF) to discriminate postoperative scar tissue distribution on the palate. METHODS: Nineteen male Wistar rats at the 20th postnatal day were divided into experimental and control groups. In the experimental group, lateral palatal mucoperiosteum was excised to form scar tissue on the palate. At the 11th postnatal week, changes in the palatal blood flow were recorded with LDF in both groups by occluding exposed common carotid arteries. Perfusion values of nonoccluded (stable) and occluded states and the ratio of occluded to stable states were compared for scar tissue and normal tissue areas, and also for the normal tissue areas. After the LDF measurements, India ink-injected specimens and tissue sections were prepared for histological observations. RESULTS AND CONCLUSIONS: Scar tissue areas showed lower perfusion values both in the stable and occluded states, reflecting a lower vascular density in the scar tissue. The ratio of the occluded to stable states was higher in the scar tissue than in the normal tissue areas. In normal tissue areas, perfusion values of both the stable and occluded states appeared to vary, but the ratio did not vary among the areas. In the LDF study, the ratio of the occluded to stable states was considered to be the better parameter for discriminating scar tissue from normal tissue.

Animals↗
PubMed2000

The absence of impairment of cliff avoidance reaction induced by subchronic methamphetamine treatment in inbred strains of mice.

Cliff avoidance reaction (CAR), an index of behavioral teratology in rodents, can be impaired by motor, arousal, or cognitive dysfunction. We formerly reported subchronic administration of methamphetamine (MAP) induced the CAR impairment, which might reflect MAP-induced cognitive dysfunction, in three strains of rats. In this study, the effects of subchronic MAP treatment on the behavioral sensitization in stereotypy (stereotypy sensitization) and CAR were examined in two inbred strains of male mice; C57BL/6J(C57) and DBA/2J(DBA). The animals received 4 mg/kg/day MAP intraperitoneally for 28 days. There were apparent strain differences in the development of stereotypy sensitization induced by chronic MAP; DBA mice developed stereotypy sensitization quickly, but C57 did not. Unlike rats, neither strains of mice showed the CAR impairment. These results suggest that chronic MAP (4 mg/kg) administration did not introduce any cognitive dysfunction measured by CAR in the two inbred mice, DBA and C57. The discrepancy between rats and mice is still unclear. It might relate to the species-selective effect of MAP on the CAR impairment. Further studies should to be required.

Animals↗
PubMed2000

Immunohistochemical demonstration of nerve terminals in the whole hard palate of rats by use of an antiserum against protein gene product 9.5 (PGP 9.5).

Sensory innervation of the entire hard palate was investigated in the rat using serial sections immunostained for protein gene product 9.5 (PGP 9.5), a neuronal marker. PGP 9.5-immunoreactive nerve endings were widely distributed in the hard palate, but the innervation pattern and density differed among portions. They were numerous at papillary protrusions including the incisal papilla, antemolar/intermolar rugae, and postrugal filiform papillae. Immunoreactive free nerve endings gathered at the summits of the connective tissue papillae, some of them entering deeply into the epithelium. Electron microscopy demonstrated that nerves in the postrugal filiform papillae reached the stratum corneum. The atrial region, possibly the most sensitive in the hard palate, showed unique innervation: its anterior part, adjacent to incisors, developed intraepithelial networks of fine and beaded nerves, whereas its posterior part revealed cone-shaped nerve terminals formed on the connective tissue papillae of the atrial folds which comprised two lines of longitudinal flaps. Taste bud-like corpuscles gathered in the medial walls of the incisal canals and in the "Geschmacksstreifen" (taste stripes) present at the most anterior part of the soft palate. The hard palate of the rat is thus richly innervated, and is characterized by region-specific nerve endings which may be involved in mechano- and chemoreception in the oral cavity.

Animals↗
PubMed2000

Spontaneous vertebral arteriovenous fistula--case report.

A 57-year-old male presented with a rare case of spontaneous vertebral arteriovenous fistula manifesting as radiculopathy of the right arm, subsequently associated with pulsating tinnitus and vascular bruit in the nape. He had a past history of chiropractic-induced vertebrobasilar infarction. Angiography showed a simple and direct fistula between the third segment of the right vertebral artery and the epidural veins at the C-1 level, where the artery runs backward above the arch of the C-1 just proximal to the penetration of the dura. The fistula was successfully obliterated by coil embolization, resulting in rapid improvement of the signs and symptoms. Mechanical compression to the nerve roots by the engorged epidural veins with arterial pressure was considered to be the major cause of radiculopathy. Vertebral artery dissection induced by chiropractic manipulation is most likely responsible for the development of the fistula.

Arteriovenous Fistula↗
PubMed2000

Migration of the shunt tube after lumboperitoneal shunt--two case reports.

A 60-year-old male and a 36-year-old female suffered shunt migration after lumboperitoneal shunt procedures, upward into the spinal subarachnoid space and downward into the abdominal cavity, respectively. Defects of the fixation devices in the shunt system are considered the main cause in both cases. Upward migration of the lumbar tube in the subarachnoid space is extremely rare. We suppose that raised abdominal pressure is related to this unusual complication.

Adult↗
PubMed2000

Persistence of hepatitis B surface antibody levels after vaccination with a recombinant hepatitis B vaccine: a 3-year follow-up study.

We conducted a 3-year follow-up study of 2,008 individuals for the persistence of antibody levels after vaccination with a recombinant hepatitis B vaccine. At 1 month after vaccination had been completed 96.3% of subjects had acquired protective HB surface (HBs) antibody titers on passive hemagglutination assay (PHA) of 2, and 3 years after completion of the vaccination 63.1% had acquired similar titers. The titer decreased below this level after 3 years in 34.5% of subjects who had initially acquired protective antibody titers. The mean acquired HBs antibody titer on PHA was 2 at 1 month and 2 at 3 years after completion of the vaccination. The regression line for these changes was expressed as logY = 1.800-0.24X by the least squares method. The antibody level was estimated to decrease to 2 at 37 months and to seronegativity at 75 months. On the basis of the relationship between PHA antibody titers and the period of their persistence, the persistence of antibody levels after vaccination with a recombinant vaccine can be estimated from the acquired antibody titer determined 1 month after completion of the vaccination, as with plasma-derived vaccines.

Adult↗
PubMed2000

Presence of a glycan at a potential N-glycosylation site, Asn-281, of bovine lactoferrin.

This work was performed to clarify the differences in glycan moieties between multiple molecular mass forms of bovine lactoferrins (bovine lactoferrins-a and -b). After digestion of both bovine lactoferrins with cyanogen bromide and V8 protease, glycopeptides were successively purified by concavalin A affinity chromatography and HPLC on an octadecylsilyl column. Four glycopeptides glycosylated at Asn-233, -368, -476, and -545 were obtained from both hydrolysates of bovine lactoferrins-a and -b. On the other hand, a glycopeptide glycosylated at Asn-281 was only detected in hydrolysate of bovine lactoferrin-a, indicating that bovine lactoferrin-a possessed five N-glycosylated sites. The glycan linked to Asn-281 of bovine lactoferrin-a was found to consist of fucose, galactose, and N-acetylgalactosamine in addition to mannose and N-acetylglucosamine. HPLC analysis of this glycan on a normal phase column showed that peaks of several glycans were detected. These glycans changed to one major glycan consisting of only mannose and N-acetylglucosamine on exoglycosidase digestion. From these results, this glycan seemed to be of the complex type and possess heterogeneous structure.

Acetylgalactosamine↗