Search PubMed⌕ Search

Biomedical subjects

S Ohtani

Publications and source records attributed to S Ohtani.

At least 55 records · Page 3Linked to original sources
PubMed1997

False aneurysm of the axillary artery caused by graft infection: report of a case.

A 77-year-old man presented to our hospital following the sudden onset of left subclavicular swelling, 8 years after undergoing subtotal removal of an axillofemoral bypass. Computed tomography revealed a rupture of the left axillary artery with the formation of a false aneurysm. Emergency surgery was performed in the form of an extraanatomic, axillo-axillary bypass with resection of the false aneurysm. Prior to removal of the false aneurysm, the subclavian artery was ligated via a left thoracotomy to minimize blood loss. The pathogen was identified as Proteus mirabilis, which is a rare causative organism for prosthetic graft infection. This case report demonstrates that total removal of the graft with revascularization should be performed for graft infections.

Aged↗
PubMed1997

The argyrophilic nucleolar organizer region (Ag-NOR) score in invasive ductal carcinoma of the pancreas.

The biological malignancy of pancreatic carcinoma was evaluated by determining the score of the argyrophilic nucleolar organizer region (Ag-NOR) in resected specimens, and comparing it with the various clinicopathological factors and long-term results of 38 patients who underwent surgical resection for invasive ductal carcinoma of the pancreas between 1977 and 1992, in whom the Ag-NOR could be stained. The Ag-NOR analysis of pancreatic carcinomas from the 38 patients resulted in a mean Ag-NOR score of 3.82 +/- 0.62, which was significantly (P < 0.01) higher than the mean score of 1.72 +/- 0.28 observed in normal pancreatic tissues obtained from 20 of these patients. The mean Ag-NOR score significantly increased in patients with anterior capsular infiltration (s) (P < 0.01), posterior tissue infiltration (rp) (P < 0.01), and lymph node metastasis (n) (P < 0.05) compared to those without these factors. The rate of curability A or B was only 13.0% in patients with a high Ag-NOR score of > or = 3.80 in comparison to 66.7% in those with a low Ag-NOR score of < 3.80. The 3-year survival rate was significantly (P < 0.05) higher in the low Ag-NOR score group than in the high Ag-NOR score group. These results suggest that the Ag-NOR score can serve as an indicator of the biological malignancy of pancreatic carcinoma, and of the patients' prognosis.

Carcinoma, Ductal, Breast↗
PubMed1997

Effects of dietary fat sources on lipid metabolism in growing chicks (Gallus domesticus).

The effect of dietary fat sources with different degrees of unsaturation and double bond positioning on lipid metabolism was studied in growing chicks. Four-week-old chicks were given semi-purified diets containing 6% palm oil (PLO), 6% safflower oil (SFO), 3% safflower oil and 3% linseed oil (SFO + LNO), 6% linseed oil (LNO), or 3% linseed oil and 3% fish oil (LNO + FO) with 0.5% cholesterol supplementation. Cholesterol ester content in the liver and serum of chicks fed PLO diet was significantly higher than that of other diet groups. Liver triacylglycerol and free cholesterol contents were significantly decreased in chicks fed a diet containing n-3 fatty acids (i.e., linseed oil or fish oil). Serum triacylglycerol level was also decreased by feeding the LNO or LNO + FO diet. The activity of serum lecithin-cholesterol acyltransferase was not affected by dietary treatments. Fecal neutral steroid excretion was significantly increased in the LNO+FO diet group as compared with the SFO + LNO or LNO diet groups. With the increase in linseed oil levels, the levels of C18:2n6 and C20:4n6 fatty acids in tissue lipids decreased, but C18:3n3 and C20:5n3 were gradually increased. The levels of longer chain n-3 fatty acids (i.e., C20:5n3 or C22:6n3) in chicks fed a diet containing fish oil (LNO + FO diet) were significantly increased compared to those fed linseed oil with a corresponding level. These results demonstrated that dietary fat enriched with alpha-linolenic acid and longer chain n-3 fatty acids have stronger effects on lowering serum lipid levels than dietary fat composed of either saturated, or n-6 fatty acids, but both n-3 fatty acids sources show differing effects on the deposition of longer chain n-3 fatty acids into tissue lipids.

Animals↗
PubMed1997

Up-regulated expression of angiotensin II type 1 receptor gene in human pathologic hearts.

BACKGROUND: An accumulation of evidence suggests that the local renin-angiotensin system plays a role in the development of cardiac hypertrophy in vivo; however, it remains unknown how the expression of angiotensin II type 1 receptor (AT1), which mediates most of the cardiovascular effects of angiotensin II, is regulated in the left ventricles of human pathologic hearts. METHODS AND RESULTS: Expression of AT1 gene in the left ventricle wall of 14 autopsied human hearts was examined by reverse transcription polymerase chain reaction. The levels of AT1 messenger RNA relative to those of beta-actin messenger RNA in the left ventricle wall were increased 3.8-fold in the hearts with dilated cardiomyopathy (n = 4, P < .05) and 6.2-fold in the noninfarcted areas of hearts with old myocardial infarction (n = 4, P < .05), compared with the control hearts without any cardiac disease (n = 6). The increases in the relative AT1 messenger RNA level showed a positive correlation with myocyte diameter in the adjacent tissue (r = .927, P < .001 for dilated cardiomyopathy and r = .934, P < .005 for old myocardial infarctions) and with the extent of fibrosis (r = .880, P < .005 for dilated cardiomyopathy and r = .690, P < .05 for old myocardial infarction). CONCLUSIONS: Expression of AT1 in these human pathologic hearts was associated with myocardial cell hypertrophy and extent of fibrosis, a finding that further emphasizes the importance of the local renin-angiotensin system in the remodeling of human hearts with dilated cardiomyopathy and old myocardial infarction.

Adolescent↗
PubMed1997

In vivo anti-tumour effect of 3'-sulphonoquinovosyl 1'-monoacylglyceride isolated from sea urchin (Strongylocentrotus intermedius) intestine.

Extracts from sea urchin intestine were screened for new anti-tumour drugs. Four glycolipids, 3'-sulphonoquinovosyl-1', 2'-diacylglyceride (A-4), 3'-sulphonoquinovosyl-1'-monoacylglyceride (2'-lyso A-4, A-5), NeuGc(alpha)2-6Glc(beta)1-1ceramide (A-6) and HSO3-8NeuGc(alpha)2-6Glc(beta)1-1ceramide (A-7), were isolated from the intestine of sea urchin, Strongylocentrotus intermedius, and characterized by means of proton nuclear magnetic resonance spectroscopy and fast atom bombardment mass spectrometry. When tested for cytotoxic activity against tumour cells in vitro, A-5 showed significant activity, but A-4, -6 and -7 did not. In addition, the hydrophilic derivatives of A-4 or -5 had no cytotoxicity. Furthermore, the anti-tumour effects on nude mice bearing solid tumours of a human lung adenocarcinoma cell line A-549 were evaluated in vivo using A-4 and -5. As a result, A-5 was found to be significantly effective in suppressing the growth of solid tumours, whereas A-4 had no effect. Pathologically, the solid tumours showed haemorrhagic necrosis areas after treatment with A-5. In this study, we have demonstrated the anti-tumour effect of sulphonoquinovosyl-lysoglyceride (A-5), which provides important information that this sulpholipid could be a useful drug for cancer chemotherapy.

Adenocarcinoma↗
PubMed1997

Dietary safflower phospholipid reduces liver lipids in laying hens.

This experiment was conducted to determine the effects of dietary safflower phospholipids (crude safflower phospholipid and purified safflower phospholipid) on performance and lipid metabolism of laying hens. Sixty-week-old Single Comb White Leghorn laying hens were divided into four groups of seven birds each, and were given one of four experimental diets containing 5% beef tallow (served as a control, tallow), a mixture of safflower oil and palm oil (SP-oil), crude safflower phospholipid (Saf-PLcrude), or purified safflower phospholipid (Saf-PL) for 7 wk. Egg production ratio and daily egg mass were significantly higher in hens fed Saf-PLcrude diets than in hens of the other diet groups. There were no significant differences in egg weight among groups. Liver cholesterol and triglyceride contents were significantly decreased in all treated groups as compared with the control. The activity of hepatic 3-hydroxy-3 methylglutaryl coenzyme A reductase was the highest in hens fed the Saf-PLcrude diet. Serum esterified cholesterol concentration was decreased by feeding of SP-oil, Saf-PLcrude, or Saf-PL diets. Serum lecithin-cholesterol acyltransferase activity was highest in hens fed the tallow diet. Excreta neutral steroid excretion was significantly increased in the Saf-PLcrude or Saf-PL diet groups, although acidic steroid excretion was not affected by dietary treatments. Total cholesterol, triglyceride, and phospholipid contents in egg yolks were not different for any dietary treatments. The fatty acid compositions of egg yolks from hens fed Saf-PLcrude diets were not different with those fed the SP-oil diet, although eggs of hens fed the Saf-PL diet showed lower total polyunsaturated fatty acids. These results suggest that dietary safflower phospholipids may be a valuable ingredient to layers for reducing liver triglycerides and serum cholesterol without any adverse effects.

Animals↗
PubMed1997

Effect of oxygen concentration and free radicals on in vitro development of in vitro-produced bovine embryos.

The effects of free radicals and hypotaurine on the development of bovine embryos produced by in vitro fertilization of in vitro-matured oocytes were examined. Embryos that developed to the 4- to 6-cell stage after in vitro fertilization were cultured without feeder cells in TCM199 medium supplemented with 1% calf serum (CS) under either 5% CO2 in air or 5% O2, 5% CO2 and 90% N2. The percentages of blastocysts (including early, expanding, and hatched stages) that developed under 5% O2 was higher (P < .01) than the percentage of those that developed under 20% O2. The respective percentages in 5% vs 20% O2 concentration were as follows: blastocysts (d 8), 49% vs 17%; expanded blastocysts (d 8), 19% vs 6%; hatched blastocysts (d 10), 16% vs 0%. The development of embryos to blastocysts was suppressed (P < .05) when oxygen radicals were generated in culture medium by 2,2'-azobis(2-amidinopropane) dihydrochloride (AAPH) under both 5% and 20% O2. The addition of hypotaurine permitted the development of embryos to blastocyst stage in medium with AAPH only under 5% O2 (P < .05), but superoxide dismutase (SOD) did not permit the development of embryos to blastocysts. Alternatively, when embryos were cultured in medium without AAPH, the rates of development into blastocysts under 20% O2 increased (P < .05) by the addition of hypotaurine and SOD. However, under 5% O2, the rates of blastocyst formation were not improved by addition of hypotaurine and SOD. Moreover, the cell numbers of blastocysts cultured in medium containing hypotaurine were greater (P < .01) than those of blastocysts cultured in medium without hypotaurine. It is concluded that hypotaurine may exert beneficial effects on in vitro development of bovine embryos under both 20% O2 and 5% O2 of gaseous conditions.

Amidines↗
PubMed1997

Estimation of age from teeth by amino acid racemization: influence of fixative.

To determine the age of a subject from teeth accurately utilizing the racemization rates of amino acids, standard samples of the same tooth species from the same jaw are necessary as controls, as well as data for identification. However, standard teeth are generally stored in fixatives such as ethanol and formalin. We investigated and compared the degree of progression of racemization of dentinal aspartic acid in teeth stored in 95% ethanol, 10% formalin, or 10% neutral formalin fixatives. The racemization rate of dentinal aspartic acid in teeth stored in 10% neutral formalin was the highest, followed by that for teeth stored in 10% formalin then that for teeth stored in 95% ethanol. Teeth stored in these fixatives at 15 degrees C showed almost no progression of racemization. The racemization ratio (D/L ratio) in teeth extracted 10 years previously was almost unchanged from that at the time of extraction, and allowed an accurate evaluation of the subjects age at tooth extraction.

Age Determination by Teeth↗
PubMed1997

Different racemization ratios in dentin from different locations within a tooth.

It has been reported that the amount of D-aspartic acid in dentin is highly correlated with age. However, further studies are necessary to determine the details of this correlation. We quantitatively determined L- and D-aspartic acids in dentin, and from the data calculated the D/L ratio. We did not find any statistically significant difference in the D/L ratio between the same type of left and right teeth from the same jaw, and between the vestibular and lingual sides of the root dentin. However, the D/L ratio was significantly higher on the lingual side than on the labial side of the dentin. Although the D/L ratio in young subjects was comparatively high in the tooth crown and decreased toward the apex of the root, we did not always observe such a tendency in middle- to advanced-age individuals. These results indicate that the ratio of D/L aspartic acid in dentin varies between the lingual side and vestibular side of the crown dentin. Therefore, it appears that the racemization rate of aspartic acid is not uniform but differs with the region of the dentin, and may be affected by differences in factors such as temperature.

Adolescent↗
PubMed1997

Gastrointestinal absorption of recombinant human insulin-like growth factor-I in rats.

The GI absorption of recombinant human insulin-like growth factor-I (rhIGF-I) and its improvement were investigated in rats. The 125I-rhIGF-I rapidly degraded to the trichloroacetic acid-soluble form in the small-intestinal contents, but it was relatively stable in the gastric and large-intestinal contents and in the subcellular fraction of the small-intestinal mucosa. To protect rhIGF-I from degradation in the small-intestinal contents, the effect of some adjuvants was examined and their degradation was markedly inhibited by the presence of aprotinin or casein. After p.o. administration of 125I-rhIGF-I at the dose of 1.0 mg/kg, trichloroacetic acid-precipitable radioactivity in the plasma was periodically determined. We found that a considerable amount of rhIGF-I was absorbed into the systemic circulation and that the bioavailability was 9.3%, which is much greater than that of insulin. The coadministration of aprotinin and that of casein enhanced the bioavailability further: 46.9% and 67.0%, respectively. Radioimmunoassay using a monoclonal antibody for rhIGF-I confirmed the high bioavailability of immunoreactive rhIGF-I. From gel chromatography of plasma, the radioactivity in the plasma was found to be in the form of high-molecular-weight complexes. The mechanism for the uptake of rhIGF-I by intestinal mucosa may be absorptive-mediated endocytosis.

Animals↗
PubMed1997

[Two cases of personal identification from dental information].

We describe two cases in which unknown bodies were positively identified from dental information and biochemical examination using tooth materials. In one case, a charred body was positively identified with little effort by comparison of antemortem dental records (dental chart and dental X-ray film) with postmortem data. In the other case, although the unknown individual had dental treatment, the police were unable to obtain the antemortem dental records of the victim. We then conducted biochemical analysis of teeth, facilitating personal identification using DNA analysis and age estimation based on aspartic acid racemization. The mutation obtained from the sequence of mtDNA and the genotypes of HLADQ alpha, HPRTB and ABO blood groups including the data for estimated age supported the kinship between the unknown individual and his mother. The data for maternally inherited mtDNA were of great importance in this case, since it was possible to obtain DNA from the mother. Dental identification in one of the most accurate methods of personal identification if suitable antemortem records are available. In the absence of such records, biochemical analysis of teeth also makes it possible to increase the probability of correct personal identification.

Adult↗
PubMed1997

Age estimation from racemization rate using heated teeth.

The racemization ratio (D/L ratio) of aspartic acid was determined in soluble peptide and total amino acid extracted from the dentine of experimentally-heated and unheated teeth. The ratio was higher in heated than in unheated teeth for total amino acid, but approximately the same for soluble peptide. Although the estimated age for total amino acid was much greater than the true age for heated teeth, it was approximately the same for total amino acid in unheated teeth and for soluble peptide in heated teeth and unheated teeth. These results suggest that age calculated from the D/L ratio of dentinal soluble peptide from burned bodies is sufficiently accurate for this parameter to be used to estimate age in teeth from burned bodies.

Adult↗
PubMed1997

Sequencing mitochondrial DNA from a tooth and application to forensic odontology.

Genetic identification can be complicated by long intervals between the time of death and examination of tissues, and sometimes only bone and teeth may be available for analysis. Several investigators have described the isolation of nuclear DNA from these materials, but all have indicated that the DNA is significantly degraded. Recently, the polymerase chain reaction (PCR) and direct DNA sequencing have enabled rapid and reliable characterization of specific highly polymorphic DNA sequences from different individuals. Above all, mitochondrial DNA sequences offer several unique advantages for the identification of human remains. The isolation of mtDNA from a tooth and the symmetrical PCR amplification and direct DNA sequencing of its most polymorphic regions are reported.

Alleles↗
PubMed1996

Tumour necrosis factor is expressed in cardiac tissues of patients with heart failure.

Tumour necrosis factor (TNF), a cytokine produced mainly by macrophages, has also been found in vascular smooth muscle cells. Elevated serum levels of TNF have been reported in various cardiac diseases, especially congestive heart failure (CHF). Although the myocardium produces several cytokines, the expression of TNF in human cardiac tissue has not yet been demonstrated. We examined TNF expression in right atrial (RA) specimens obtained from 15 patients during cardiac surgery with immunohistochemistry using an anti-human TNF monoclonal antibody, enzyme-linked immunosorbent assay (ELISA) and reverse transcriptase polymerase chain reaction (RT-PCR). TNF immunoreactivity was found only in cardiac myocytes and some vascular smooth muscle cells of small vessels of specimens from patients with severe CHF (3/5), and not in those from patients without severe CHF (0/10). ELISA of four RA specimens revealed that RA tissues from two patients with severe CHF contained more TNF than did those from two patients without severe CHF (3.1 and 4.7 pg/mg vs. 0.1 and 0.3 pg/mg). RT-PCR revealed TNF mRNA in all seven cases we examined. It was concluded that TNF mRNA is expressed by atrial tissue. The production of immunoreactive TNF-like peptides by myocytes and vascular smooth muscle cells is augmented in patients with severe CHF.

Aged↗
PubMed1996

Long-term outcome of patients who received Starr-Edwards valves between 1965 and 1977.

To determine the risk factors relating to long-term outcomes of the Starr-Edwards ball valve, data from 150 patients (75 males, 75 females; age range 9-67 years); who underwent valve replacement (44 aortic, 106 mitral) between 1965 and 1977 at Niigata University were reviewed retrospectively. Valve models 6120/6320 and 1260/2320 were mainly used in mitral and aortic positions, respectively. The cumulative follow-up period was 2227.4 patient-years. Using the Kaplan-Meier life-table method, actuarial probability of freedom from valve-related mortality, morbidity and thromboembolism were analysed. Thirteen patients died from various causes during hospitalization. Some 80 patients suffered 97 instances of valve-related morbidity and 58 died during follow-up (up to 28 years). Patient age > 50 years affected the actuarial probability of freedom from valve-related mortality in the entire group (P < 0.05). Valve type and the year of operation were discriminative predictors of thromboembolic complications in the entire group (both P < 0.05) and in the mitral valve replacement group (P < 0.01 and P < 0.001). However, only the year of operation affected the actuarial probability of freedom from all valve-related morbidity in the entire group and in the mitral valve replacement group (both P < 0.05). Univariate analysis revealed that age at surgery, valve type, and the year of operation were related to late postoperative outcome in patients who received a Starr-Edwards ball valve between 1965 and 1977.

Actuarial Analysis↗
PubMed1996

Intestinal motility after massive small bowel resection in conscious canines: comparison of acute and chronic phases.

To evaluate intestinal function after 80% massive distal small bowel resection (MSBR), we continuously monitored interdigestive and postprandial bowel motility using bipolar electrodes and/or contractile strain gauge force transducers in conscious beagle dogs before and at 2-4 weeks (acute postoperative phase; acute phase) and 8-13 months (chronic postoperative phase; chronic phase) after the surgery. Fasting duodenal migrating myoelectric (or motor) complexes (MMC) occurred at longer intervals in the acute phase after 80% MSBR than in control beagles. Intervals between duodenal MMC in the chronic phase were similar to those found in control beagles. MMC arising from the duodenum were often interrupted before the jejunum above the anastomosis in the acute phase, and a slight recovery of propagation frequency to the jejunum above the anastomosis was observed in the chronic phase. However, duodenal MMC did not migrate smoothly to the terminal ileum in both groups. In the acute phase, the velocity of duodenal MMC propagation was slowed in every intestinal segment, including the duodenum and the jejunum above the anastomosis, and had not recovered even long after the operation. The duration of the postprandial period without duodenal MMC was prolonged significantly in the acute phase postoperatively. Although it shortened in the chronic phase, it still remained significantly longer than in controls. These findings suggest that changes in gut motility after MSBR tend to compensate for the shorter intestine and maintain small bowel absorption early postoperatively. However, these compensatory changes decrease over the long term, and their adaptive contributions to increased intestinal absorption may decrease as well.

Anastomosis, Surgical↗
PubMed1996

Endothelin-1 and its receptor in hypertrophic cardiomyopathy.

Endothelin-1, a potent vasoconstrictor produced by vascular endothelial cells, activates the hypertrophic program in cultured heart muscle cells. However, the role of endothelin-1 in cardiac hypertrophy in humans is unknown. Therefore, we studied hypertrophic cardiomyopathy patients with normal pulmonary arterial pressure, in whom cardiac hypertrophy is a specific feature of the disease. Radioimmunoassay with a monoclonal antibody to human endothelin-1 showed that the plasma level of immunoreactive endothelin was more than twofold higher in hypertrophic cardiomyopathy patients than in control subjects (P < .005). In situ hybridization analysis of endomyocardial biopsy specimens showed positive signals of endothelin-1 type A receptor mRNA in ventricular myocytes of all specimens. The receptor expression in ventricular myocytes was similar between hypertrophic cardiomyopathy patients and control subjects. We propose that endothelin-1 might represent an important factor involved in hypertrophic cardiomyopathy. Whether endothelin-1 plays a causal role in cardiac hypertrophy or is a marker of its occurrence needs to be clarified.

Analysis of Variance↗