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S Ohtani

Publications and source records attributed to S Ohtani.

At least 91 records · Page 5Linked to original sources
PubMed1995

Studies on age estimation using racemization of aspartic acid in cementum.

An attempt was made to estimate the age of cementum using the racemization method, which focuses on the ratio of D- and L-aspartic acids (referred to as the 'D/L ratio'). Using the whole cementum, the correlation coefficients between the D/L ratio and age were r = 0.984 to 0.997. When the use of incisors and premolars was compared, the former gave better results than the latter. We then made a comparison of cementum, enamel and dentin, using a first premolar from the same individual. For each component tissue the correlation of D/L ratio with the actual age was calculated and the highest value was shown for dentin at r = 0.992, followed by cementum at r = 0.988 and enamel at r = 0.961. These results show that the racemization reaction in cementum proceeds at a constant rate, and confirm that cementum, like dentin, is a tissue with very low metabolism. Therefore, it is clear that accurate estimation of age is practically possible using the amino acid racemization method for cementum.

Adult↗
PubMed1995

[Small bowel metastasis from large cell carcinoma of the lung: report of a case].

The case of a 44-year-old man with metastatic tumor of the small intestine from large cell carcinoma of the lung was reported. The patient underwent exploratory thoracotomy because of tumor invasion into the left ventricle. He was discharged from our department after chemotherapy and irradiation. However, he was again admitted because of the development of anemia secondary to melena. An abdominal ultrasonography revealed ascites and tumor of the small intestine. Symptoms of ileus also developed. A laparotomy was performed. The metastatic tumors were found in the jejunum, and resection of jejunum was performed. The postoperative course of the patient was uneventful, and he survived one month after laparotomy. Small bowel metastasis of lung cancer, which is unusual pattern of metastasis, is also reviewed.

Adult↗
PubMed1994

Age estimation by aspartic acid racemization in dentin of deciduous teeth.

In forensic dental medicine, one of the most important endeavors is the estimation of age. We have studied the method of age assessment using the D/L ratio of aspartic acid from the dentin. The age of deciduous teeth has been estimated by measuring the racemization reaction of this amino acid. The results of the present study indicated that the measured D/L ratio for the dentin of deciduous teeth was highly correlated with the real age (r = 0.824 - 0.981 (sigma = +/- 0.5 to +/- 1.3). These results indicate that age can be accurately estimated from the dentin of deciduous teeth, as it can when permanent teeth are used, and that the D/L ratio is more highly correlated with age than is the eruption time of permanent teeth.

Adolescent↗
PubMed1994

Quantitation of urinary 1,2,3,4-tetrahydro-beta-carboline and 1-methyl-1,2,3,4-tetrahydro-beta-carboline by high-performance liquid chromatography.

A high-performance liquid chromatographic method was developed to quantify 1,2,3,4-tetrahydro-beta-carboline (TBC) and 1-methyl-1,2,3,4-tetrahydro-beta-carboline (MTBC) in human urine. Urine samples with added internal standard were subjected to a reaction with fluorescamine and solvent extractions to remove the precursor tryptamine, which readily condenses with aldehydes in samples and reagents. Such a pretreatment completely suppressed the artifactual formation of TBC and MTBC during analytical procedures. The purified original tetrahydro-beta-carbolines and the internal standard were separated by reversed-phase ion-pair chromatography with fluorescent detection. Their simultaneous separation was automatically completed in a short time (< 12 min). Both TBC and MTBC were quantified at ng/mL concentrations. The quantitative results revealed a wide variation in urinary levels of TBC and MTBC, possibly indicating that their considerable amounts excreted in the urine originate from dietary sources.

Adolescent↗
PubMed1994

New modification of the Damus-Kaye-Stansel operation.

We report a successful modification of the Damus-Kaye-Stansel operation for transposition of the great arteries when the coronary arteries are unsuitable for transfer. The procedure includes creation of a neoaorta with end-to-end anastomosis of the proximal pulmonary artery to the distal ascending aorta and creation of an aortopulmonary window between the proximal great arteries. A valved conduit is interposed between the right ventricle and the distal pulmonary artery.

Aorta↗
PubMed1994

Resulting long-term intestinal motility in dogs following construction of a reversed jejunal segment after extensive small bowel resection.

To evaluate the long-term function and effective motility of a reversed jejunal segment after extensive small bowel resection, the authors continuously measured postoperative bowel motility during interdigestive and postprandial periods in conscious dogs 6 to 10 months after surgery. The long-term findings were compared with previously reported short-term results measured 2 to 4 weeks after the operation. In the long-term follow-up dogs with a 20-cm reversed jejunal segment constructed after extensive (75% to 80%) small bowel resection, the fasting duodenal migrating myoelectric (or motor) complex (MMC) was often interrupted in the jejunum above the reversed segment, and did not migrate smoothly to the reversed segment or terminal ileum. The MMCs arising from the duodenum predominantly propagated to the ileum through the inherent anatomic continuity of the bowel. In addition, brief small discordant contractions were frequent in the reversed segment and the jejunum, above the proximal anastomosis. These findings are similar to those of the MMC propagation pattern noted 2 to 4 weeks after surgery. However, the postprandial duration without duodenal MMC activity was significantly shorter in the dogs with long-term follow-up than in those with short-term follow-up (both were longer than in control dogs). Marked dilatation of the jejunum and reversed jejunal segment was noted across the proximal anastomosis. These results suggest that the transit time and passage of intestinal contents can be delayed and stagnated for at least 10 months after extensive small bowel resection with a 20-cm reversed jejunal segment.(ABSTRACT TRUNCATED AT 250 WORDS)

Anastomosis, Surgical↗
PubMed1994

Multiplicity of abnormal dystrophin in Becker muscular dystrophy. A Becker muscular dystrophy gene frequently produced two smaller sizes of dystrophin.

Dystrophin is a muscle cytoskeletal protein with a molecular mass (MM) of approximately 420 kDa and an isoelectric point (pI) of approximately 5.5, which is abnormal in size and/or abundance in Becker muscular dystrophy (BMD). We investigated the abnormality of dystrophin molecule in muscles biopsied from 23 BMD patients using the two-dimensional gel electrophoresis (TDGE). We found 7 protein spots which reacted specifically with the monoclonal anti-dystrophin antibody (mAb) A1C raised against N-terminal domain of the normal dystrophin. These spots were focused on the two-dimensional gel at the same position as the normal dystrophin (#1), at the position with MM approximately 480 kDa/pI approximately 5.35 (#2), the position with MM approximately 400-330 kDa/pI approximately 5.51-5.47 (#3), the position with MM approximately 300 kDa/pI approximately 5.4 (#4), the position with MM approximately 235-250 kDa/pI approximately 5.53-5.5 (#5), the position with MM approximately 165 kDa/pI approximately 6.0 (#6), and the position with MM approximately 160 kDa/pI approximately 5.75 (#7). These spots were classified into five patterns in individuals, that is, #1 alone in 3 patients, #3 alone in 1, the combination of #3 and 5 in 17, the combination of #1, 3 and 5 in 1 and the combination of #1, 2, 4, 6 and 7 in 1. The combination of #3 and 5 was observed in 17 of 23 patients (75%).(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1994

Determination of tetrahydro-beta-carbolines in urine by high-performance liquid chromatography with suppression of artefact formation.

A high-performance liquid chromatographic method has been developed for the determination of urinary tetrahydro-beta-carbolines. When standing tryptamine with formaldehyde and acetaldehyde under extraction conditions, the significant amounts of artefact 1,2,3,4-tetrahydro-beta-carboline (TBC) and 1-methyl-1,2,3,4-tetrahydro-beta-carboline (MTBC) were formed in a short time. Urine samples added with 2-ethyl-1,2,3,4-tetrahydro-beta-carboline (an internal standard) were treated with fluorescamine, and then with glycine, followed by serial solvent extractions. Such a pretreatment using two-step reactions removed a precursor (trypamine) by extracting its fluorescamine derivative, and enhanced the detection response by consuming excess fluorescamine. It solved the analytical problem that artefact TBC and MTBC are formed during analysis. Reversed-phase ion-pair chromatography using a C8-column and trifluoroacetic acid as a counter ion completed a base-line separation of three analytes within 10 min. The calibration graphs showed a good linearity in the range 0.1-50.0 ng ml-1 of urine samples spiked with standard TBC and MTBC. In the spike experiment, the recovery and relative standard deviation were almost 100% and less than 3.0%, respectively, for both TBC and MTBC. The proposed method enables the determination of the genuine urinary concentrations of TBC and MTBC without involving their artefacts.

Acetaldehyde↗
PubMed1994

Hepatitis C virus antibodies and virus replication in asymptomatic blood donors.

We assessed hepatitis C virus (HCV) infection in 99 asymptomatic blood donors positive using a first-generation HCV antibody assay. When tested with second-generation assays, 86 (87%) donors were reactive (group 1), 2 (2%) were indeterminate (group 2), and 11 (11%) were non-reactive (group 3). Viraemia was revealed by polymerase chain reaction in all group 1 cases. The 2 group 2 cases and 6 (55%) group 3 cases were also viraemic. Viraemia was confirmed by a branched DNA assay in the 2 group 2 cases and 4 (36%) group 3 cases. Serum HCV RNA levels were further studied using a competitive reverse transcription-polymerase chain reaction assay. All cases in groups 2 and 3 were low viraemic (range 10(4)-10(5.5) copies/ml) compared with the 9 group 1 cases examined (range 10(7)-10(9) copies/ml). No correlation was evident between viraemic levels and antibody cut-off index in the first-generation assay. These findings indicate the possibility that low levels of viraemia can occur in individuals non-reactive in second-generation HCV antibody assays.

Adult↗
PubMed1994

Endothelin-1-selective receptor in the arterial intima of patients with hypertension.

Endothelin-1 is a potent vasoconstrictor produced by vascular endothelial cells. A recently cloned endothelin-1-selective receptor, the endothelin-A receptor, mediates the vasoconstrictive action of endothelin-1. Because endothelin-1 also possesses mitogenic properties, it may play a role in regulating the proliferation of intimal smooth muscle cells. In this study, we analyzed the expression of endothelin-A receptor gene in the thickened arterial intima of patients with hypertension. Internal mammary artery specimens obtained from 12 patients undergoing cardiovascular surgery were subjected to in situ hybridization using a digoxigenin-labeled cRNA probe. High, homogeneous signals of endothelin-A receptor mRNA were observed in the medial smooth muscle cells of all vessels examined but not in the endothelial cells. Patients with hypertension displayed more severe intimal thickening than those without hypertension. Immunohistochemical analysis suggested that almost all of the intimal proliferative cells originated from smooth muscle cells. In contrast to media, endothelin-A receptor mRNA signals in intimal smooth muscle cells were low and heterogeneous. In the thickened arterial intima of hypertensive patients, the signals were detected just beneath the luminal endothelium but not deep in the intimal smooth muscle cell layer. By contrast, staining with anti-alpha-smooth muscle actin antibody was more intense in the deep layer than in the subendothelium. These findings suggest that the modulation of endothelin-A receptor gene expression in smooth muscle cells differs between the intima and media. Its regulated expression in intimal smooth muscle cells might affect the proliferative activity of these cells in patients with hypertension.

Aged↗
PubMed1994

Development of the motor activity of the rat gastrointestinal tract by in vitro measurement.

To clarify the postnatal developmental changes of the motor activity of the gastrointestinal tract, the frequency and amplitude of spontaneous intraluminal pressure of the isolated stomach, duodenum, jejunum, and ileum of the 1- to 5-week-old rat and adult (over 12 weeks old) were examined in vitro. The spectral frequencies of the spontaneous motor activity of 1- to 2-week-old rat were significantly lower than those of the adult. They became similar to the values of the adult at 3-4 weeks after birth. The amplitudes of spontaneous motor activity of 1- to 3-week-old rats were significantly smaller than those of adults. They became similar to the values of adults at 4 weeks after birth. Body weight, stomach wet weight and the length of the total intestine increased gradually and they were still below the values of the adult even at 5 weeks after birth. The stomach was filled with just milk until the end of 2 weeks. However, by the end of 3-4 weeks, milk and solid food were found in the stomach. By the end of 5 weeks, just solid food was seen in the stomach. Therefore, the motor activity of the gastrointestinal tract at birth seems immature and gradually develops postnatally. It seems to be mature by the end of 3-4 weeks after birth. Interestingly, the time of the pacemaker or motor maturity of the gastrointestinal tract according to spontaneous frequency or pacemaker activity and amplitude seemed almost consistent with the weaning time.

Age Factors↗
PubMed1994

An immunohistochemical study on pulmonary surfactant of infants diagnosed as sudden infant death syndrome.

Pulmonary tissues from 22 autopsy cases diagnosed as sudden infant death syndrome (SIDS) were examined by immunoperoxidase method using monoclonal antibodies against human pulmonary surfactant apoproteins. In all cases except one, a moderate or large amount of pulmonary surfactant existed in the alveolar spaces. In the cytoplasm of the alveolar type II cells of most cases, a variable number of reaction products were also recognized. This study suggested that SIDS babies suffered lethal hypoxic state, but the staining intensity of pulmonary surfactant did not show a clear difference in sleeping positions.

Humans↗
PubMed1994

Tooth-based age estimation of an adipocerated cadaver using the amino acid racemization method.

We attempted to estimate the age of a completely adipocerated unidentified body using the aspartic acid racemization reaction (racemization method). The material used to make the estimate consisted of two teeth, the right and left lower first premolars, and for comparison five lower first premolars from persons of known age were used. From testing of the specimen teeth, it was estimated that age at the time of death was 39 +/- 3 years. Later, the body was identified as that of a woman who had been murdered 6 years before at the age of 41 years, and it was possible to estimate almost precisely her age at the time of death. It was clarified that the dentin racemization reaction hardly proceeds even when the body adipocerates, under conditions in which normal tooth color and hardness are maintained.

Adult↗
PubMed1994

[Transcatheter embolization of aorto-pulmonary collateral arteries in cyanotic congenital heart disease].

Transcatheter embolization (TE) using steel coils was performed on three patients with aorto-pulmonary collateral arteries (APCAs). Case #1: In a 13-year-old boy who had undergone corrective surgery for pulmonary atresia with ventricular septal defect (PA with VSD), one APCA was embolized by the TE technique. This resulted in a remarkable improvement in postoperative pulmonary congestion. Case #2: A 13-year-old boy who had previously undergone procedures to correct tetralogy of Fallot (TOF), underwent TE for two APCAs prior to subsequent surgery before for pulmonary stenosis. The procedure abandoned one APCA because of the long narrow origin of the vessel. For the other APCA, TE was unsuccessfully performed due to the displacement of a coil into the peripheral pulmonary artery. Case #3: An 8-year-old girl with PA with VSD underwent TE for three APCAs before corrective surgery. One APCA arising from the abdominal aorta was occluded successfully. The other two were considered too small at the orifice for TE, and were ligated surgically before corrective surgery. TE is a safe and effective method for suitable cases of APCAs. However, caution should be exercised to prevent complications. The selection of appropriate coils and catheters is also important.

Adolescent↗
PubMed1994

[Reoperation with a bifurcated nonvalved extracardiac conduit for stenosis of the valved conduit and the pulmonary bifurcation after a Ross-Rastelli operation].

We report a case of successful reoperation with a bifurcated nonvalved extracardiac conduit for stenosis of the valved conduit and the pulmonary bifurcation after a Ross-Rastelli operation. The patient was 11-year-old female, who had undergone Ross-Rastelli operation with a 16 mm Carpentier-Edwards valved conduit for pulmonary atresia with ventricular septal defect at six year-old following Blalock-Taussig shunt at four year-old. She required reoperation for progressive right heart failure due to stenosis of the valved conduit and the pulmonary bifurcation. The reoperation was performed under cardiopulmonary bypass with aortic crossclamp. The stenosed valved conduit placed between the right ventricle and the right pulmonary artery was removed and replaced with 18 mm EPTFE graft. Because the direct repair of the pulmonary bifurcation stenosis was thought to be difficult, a 12 mm ringed EPTFE graft was anastomosed to the left pulmonary artery distal to the bifurcation stenosis as a branch of the 18 mm EPTFE main graft. Although transitional heart failure required IABP support in her early postoperative course, she subsequently recovered and discharged the hospital at the 37th postoperative day. Her right ventricular pressure reduced from 105 mmHg to 54 mmHg by the cardiac catheterization. She is now alive and well without any complaints.

Bioprosthesis↗