Biomedical subjects

T Shibata

Publications and source records attributed to T Shibata.

At least 55 records · Page 3Linked to original sources

PubMed2004

Genetic correlation between serum insulin-like growth factor-1 concentration and performance and meat quality traits in Duroc pigs.

This study was intended to examine whether serum IGF-I concentration is appropriate for use as a physiological predictor for genetic improvement of meat production and meat quality traits in pigs. Heritabilities and genetic correlations were estimated for these traits. The Duroc breed used in this study was selected for seven generations for average daily BW gain (DG) from 30 to 105 kg of BW, loin-eye muscle area (EM), backfat thickness (BF), and intramuscular fat (IMF) content. Serum IGF-I concentration of boars and gilts at the fourth generation of selection and that of boars, gilts, and barrows from the fifth to seventh generations of selection were measured at 8 wk (IGFI-8W) for 832 animals and again at the time they reached 105 kg of BW (IGFI-105KG) for 834 animals. A multivariate REML procedure was used to estimate genetic parameters with a model incorporating generation of selection, sex, common environmental effect of litter, and individual additive genetic effects. Heritability estimates for IGFI-8W and IGFI-105KG were 0.23 +/- 0.02 and 0.26 +/- 0.03, respectively. The estimates of common environmental effect for IGFI-8W and IGFI-105KG were 0.20 +/- 0.02 and 0.03 +/- 0.01, respectively. Positive genetic correlations were estimated between IGFI-8W and DG (0.26 +/- 0.08), EM (0.22 +/- 0.10), and IMF (0.32 +/- 0.10). Moreover, the positive genetic correlation between IGFI-105KG and EM was 0.42 +/- 0.08. These results indicate that serum IGF-I concentration at an early stage of growth was effective for prediction of IMF, but it was not a reliable physiological predictor of genetic merit of meat production traits.

Adipose Tissue↗

PubMed2004

[One-staged operation for mitral regurgitation and annuloaortic ectasia without aortic regurgitation with Marfan syndrome; report of a case].

A 32-year-old man with Marfan syndrome was admitted to our hospital for detail examination of congestive heart failure. Doppler echocardiography showed severe mitral regurgitation due to prolapse of posterior mitral leaflet. Annuloaortic ectasia without aortic regurgitation was also detected by aortography. Considering the future operative need for aortic root and ascending aorta, we performed mitral valve replacement with a mechanical valve and preventive concomitant aortic root replacement with a composite valve graft. His postoperative course was uneventful. Optimal surgical treatment of mitral regurgitation and annuloaortic ectasia in Marfan syndrome is controversial because the underlying connective tissue defect theoretically might compromise repair durability. Several surgical options for mitral regurgitation and annuloaortic ectasia in Marfan syndrome are discussed.

Adult↗

PubMed2003

Search for nu(e) from the sun at Super-Kamiokande-I.

We present the results of a search for low energy nu(e) from the Sun using 1496 days of data from Super-Kamiokande-I. We observe no significant excess of events and set an upper limit for the conversion probability to nu(e) of the 8B solar neutrino. This conversion limit is 0.8% (90% C.L.) of the standard solar model's neutrino flux for total energy=8-20 MeV. We also set a flux limit for monochromatic nu(e) for E(nu(e))=10-17 MeV.

Journal Article↗

PubMed2003

Prognostic significance of dysadherin expression in advanced colorectal carcinoma.

A novel glycoprotein, dysadherin, has an anti-cell - cell adhesion function through downregulating E-cadherin. In this study, we investigated the expressions of dysadherin and E-cadherin in 82 patients with stage II and III colorectal carcinomas to determine the correlation between the two molecules and the clinicopathologic features of each tumour. Dysadherin was not expressed in normal colorectal epithelium. Fifty-one per cent of tumours showed dysadherin immunopositivity in over 50% of cancer cells. Thirty-eight per cent of tumours showed reduced E-cadherin immunopositivity. The increased expression of dysadherin was significantly associated with lung metastasis (P=0.003). The increased expression of dysadherin had a significant impact on patient survival (P=0.0099 and 0.0036, log-rank test for overall and recurrence-free survival rate, respectively). Furthermore, tumour with increased expression of dysadherin and reduced expression of E-cadherin showed the worst prognosis (P=0.0043 and 0.0028, log-rank test for overall and recurrence-free survival rate, respectively). These results suggest that increased dysadherin expression is a significant indicator of poor prognosis for patients with advanced colorectal carcinoma.

Aged↗

PubMed2003

Search for supernova relic neutrinos at Super-Kamiokande.

A search for the relic neutrinos from all past core-collapse supernovae was conducted using 1496 days of data from the Super-Kamiokande detector. This analysis looked for electron-type antineutrinos that had produced a positron with an energy greater than 18 MeV. In the absence of a signal, 90% C.L. upper limits on the total flux were set for several theoretical models; these limits ranged from 20 to 130 macro nu(e) cm(-2) s(-1). Additionally, an upper bound of 1.2 macro nu(e) cm(-2) s(-1) was set for the supernova relic neutrino flux in the energy region E(nu)>19.3 MeV.

Journal Article↗

PubMed2003

The effects of intrusive loading on axial movements of impeded and unimpeded rat incisors: estimation of eruptive force.

Axial movements of impeded and unimpeded rat mandibular incisors were measured following application and removal of intrusive loads of 1, 2, 5, 10 and 20 mN in a stepwise order at intervals of 1h on erupting teeth. The tooth movements were recorded by a displacement detector under artificial respiration with halothane anaesthesia. The loading and unloading procedures brought about the tooth movements in two steps: an initial rapid movement immediately after application or removal of the load and a subsequent slow and gradual movement. The initial rapid intrusive or extrusive tooth movements were significantly greater in the unimpeded than in the impeded teeth at the same load. The forces to stop extrusive tooth movements, estimated from the formula of regression lines showing correlations between the intrusive loads from 0 to 5 mN and tooth movements (microm/30 min), were 4.2 mN in the impeded and 2.9 mN in the unimpeded incisors. We suggest that repeated shortenings of the rat incisor did not cause an increase in the eruptive force and that changes in the resistance of the periodontal ligament predominantly regulate the axial movement of the rat incisor.

Animals↗

PubMed2003

Effects of a single arthrocentesis and a COX-2 inhibitor on disorders of temporomandibular joints. A preliminary clinical study.

Our aim was to examine the short-term effect of combined treatment with single arthrocentesis and a COX-2 inhibitor on 26 patients with severe symptoms of temporomandibular joint (TMJ) disorders. The severity of the disorders was graded according to the degree of restriction of mouth opening and pain score on a visual analogue scale. Synovial fluid was collected from the superior joint space of the affected TMJ, and arthrocentesis was done with isotonic saline, 200ml. Subsequently, etodolac, 400mg/day, was given for 2 weeks. At 14 days, patients were re-examined and further specimens of synovial fluid were collected. Patients generally lost their symptoms and the severity of the disorders improved significantly (P<0.01). The concentrations of total protein and albumin in synovial fluid decreased with no statistical significance. However, the concentration of matrix metalloproteinase-3 and its ratios to total protein and albumin did decrease significantly (P<0.05). Our results suggest that a larger controlled study is necessary to clarify the contributory effect of arthrocentesis and etodolac for patients with severe symptoms of TMJ disorders.

Adolescent↗

PubMed2003

The human primary somatosensory cortex response contains components related to stimulus frequency and perception in a frequency discrimination task.

Somatosensory stimulation of primary somatosensory cortex (SI) using frequency discrimination offers a direct, well-defined and accessible way of studying cortical decisions at the locus of early input processing. Animal studies have identified and classified the neuronal responses in SI but they have not yet resolved whether during prolonged stimulation the collective SI response just passively reflects the input or actively participates in the comparison and decision processes. This question was investigated using tomographic analysis of single trial magnetoencephalographic data. Four right-handed males participated in a frequency discrimination task to detect changes in the frequency of an electrical stimulus applied to the right-hand digits 2+3+4. The subjects received approximately 600 pairs of stimuli with Stim1 always at 21 Hz, while Stim2 was either 21 Hz (50%) or varied from 22 to 29 Hz in steps of 1 Hz. Both stimuli were 1 s duration, separated by a 1 s interval of no stimulation. The left-SI was the most consistently activated area and showed the first activation peak at 35-48 ms after Stim1 onset and sustained activity during both stimulus periods. During the Stim2 period, we found that the left-SI activation started to differ significantly between two groups of trials (21 versus 26-29 Hz) within the first 100 ms and this difference was sustained and enhanced thereafter (approximately 600 ms). When only correct responses from the above two groups were used, the difference was even higher at later latencies (approximately 650 ms). For one subject who had enough trials of same perception to different input frequencies, e.g. responded 21 Hz to Stim2 at 21 Hz (correct) and 26-29 Hz (error), we found the sustained difference only before 650 ms. Our results suggest that SI is involved with the analysis of an input frequency and related to perception and decision at different latencies.

Adult↗

PubMed2003

An extensive outbreak of staphylococcal food poisoning due to low-fat milk in Japan: estimation of enterotoxin A in the incriminated milk and powdered skim milk.

An extensive outbreak of staphylococcal food poisoning occurred in Kansai district in Japan. As many as 13,420 cases frequently ingested dairy products manufactured by a factory in Osaka City. The main ingredient of these dairy products was powdered skim milk manufactured by a factory in Hokkaido. Staphylococcal enterotoxin A (SEA) (< or = 0.38 ng/ml) was detected in low-fat milk and approx. 3.7 ng/g in powdered skim milk. The total intake of SEA per capita was estimated mostly at approx. 20-100 ng. The assumed attack rate was considerably lower than those reported in previous outbreaks. SEA exposed at least twice to pasteurization at 130 degrees C for 4 or 2 s retained both immunological and biological activities, although it had been partially inactivated. The present outbreak was unusual in that the thermal processes had destroyed staphylococci in milk but SEA had retained enough activity to cause intoxication.

Adolescent↗

PubMed2003

Nuclear BAG-1 expression is a biomarker of poor prognosis in esophageal squamous cell carcinoma.

Apoptosis is one of the critical biological factors that correlate with the biological behavior of malignant tumors including cancer progression and clinical outcome. The present study was performed to clarify the clinical implications of BAG-1, a bcl-2 binding protein in esophageal squamous cell carcinoma (ESCC). Seventy-one cases with ESCC were investigated. Immunohistochemical study of BAG-1 was performed on resected specimens. The expression pattern of BAG-1 in nuclei and/or cytoplasm was analyzed and correlated with TNM classification, vessel invasion, survival period after surgery. BAG-1 expression in the nuclei was related to the depth of tumor invasion (P = 0.0381) but not to any other clinicopathologic parameters. The cytoplasmic staining pattern of BAG-1 exhibited no correlation with clinicopathologic parameters. Univariate analysis (P < 0.05), but not multivariate analysis, revealed significantly poor prognosis for ESCC cases exhibiting positive nucleic staining for BAG-1. Our data suggests that BAG-1 expression in the nuclei of ESCC plays an important role in tumor development and may be useful for predicting the prognosis after surgery.

Biomarkers, Tumor↗

PubMed2003

Synthesis of betaine-homocysteine S-methyltransferase is continuously enhanced in fatty livers of thyroidectomized chickens.

We examined thyroidectomized chickens in terms of plasma lipid concentration and protein expression within the liver. Although the body weight of thyroidectomized chickens was remarkably low due to growth retardation, the livers were enlarged and fatty compared to those of sham-operated chickens. An increase in phospholipid, triglyceride, and total cholesterol levels within the blood plasma of thyroidectomized chickens was observed, clearly reflecting increased lipid synthesis within the liver. Overexpression of some proteins, for example, 29- and 45-kDa proteins, was observed in thyroidectomized chicken livers by means of electrophoresis. A peptide map was made for the protein that exhibited the greatest degree of overexpression. One of them demonstrated a molecular mass of 45 kDa and an isoelectric point (pI) between 7.5 and 8.0, depending on its form. Partial N-terminal amino acid sequences were determined from three random peptides of this protein. The amino acid sequence of this protein showed a high degree of homology with the betaine-homocysteine S-methyltransferase (BHMT, EC 2.1.1.5) of some mammalian species. We identified this protein as chicken BHMT because, in addition to its sequence homology with mammalian BHMT, there were similarities were also observed between this 45-kDa protein and mammalian BHMT with respect to molecular mass and isoelectric behavior. In the liver, 10 d after thyroidectomy, the synthesis of hepatic BHMT had already been enhanced, and the high expression was maintained at 50 d of age. Generally, BHMT catalyzes the transfer of a methyl group from betaine to L-homocysteine. In addition, it seems that this enzyme is also closely related to lipid metabolism in the liver; in this study expression of BHMT in the liver corresponded to plasma lipid levels. Moreover, hypothyroidism may be directly or indirectly related to overexpression of BHMT. Due to similarities between the BHMT of chickens and mammalian species, the chicken model might provide a useful means by which to study BHMT, its role in lipid metabolism, and methods of targeting the expression of BHMT. Another 29-kDa protein was unidentified in the homology search.

Adipose Tissue↗

PubMed2003

Catecholaminergic polymorphic ventricular tachycardia: electrocardiographic characteristics and optimal therapeutic strategies to prevent sudden death.

OBJECTIVE: To investigate the clinical outcome, ECG characteristics, and optimal treatment of catecholaminergic polymorphic ventricular tachycardia (CPVT), a malignant and rare ventricular tachycardia. PATIENTS AND METHODS: Questionnaire responses and ECGs of 29 patients with CPVT were evaluated. Mean (SD) age of onset was 10.3 (6.1) years. RESULTS: The initial CPVT manifestations were syncope (79%), cardiac arrest (7%), and a family history (14%). ECGs showed sinus bradycardia and a normal QTc. Mean heart rate during CPVT was 192 (30) beats/min. Most cases were non-sustained (72%), but 21% were sustained and 7% were associated with ventricular fibrillation. The morphology of CPVT was polymorphic (62%), polymorphic and bidirectional (21%), bidirectional (10%), or polymorphic with ventricular fibrillation (7%). There was 100% inducement of CPVT by exercise, 75% by catecholamine infusion, and none by programmed stimulation. No late potential was recorded. Onset was in the right ventricular outflow tract in more than half the cases. During a follow up of 6.8 (4.9) years, sudden death occurred in 24% of the patients, 7% of whom had anoxic brain damage. Autosomal dominant inheritance was seen in 8% of the patients' families. beta Blockers completely controlled CPVT in only 31% of cases. Calcium antagonists partially suppressed CPVT in autosomal dominant cases. CONCLUSIONS: CPVT may arise in certain distinct areas but the prognosis is poor. The onset of CPVT may be an indication for an implanted cardioverter-defibrillator.

Adolescent↗

PubMed2003

[In situ graft replacement for the thoracoabdominal aortic aneurysm with abscess around the aorta; report of a case].

A 58-year-old woman who complained of epigastralgia, back pain and pyrexia was admitted for further examination. A computed tomography (CT) scan revealed an abnormal mass between the descending aorta and esophagus. Exploratory thoracotomy was performed and brown purulent fluid was drained from the mass. Postoperatively, the white blood cell count normalized and the patient become afebrile. Eleven days postoperatively, circa 500 ml of blood discharged from a chest drain tube. A CT scan demonstrated enlargement of the thoracoabdominal aorta, necessitating an emergency operation. A pseudoaneurysm was found in the thoracoabdominal aorta, with inflammation in the aortic wall. On opening the aneurysmal sac, the intima of the aorta was found to have a partial defect. In situ graft replacement of the thoracoabdominal aorta and reconstruction of the intercostal artery were performed. Finally, a pedicled omental flap was used to cover the artificial graft. Two years postoperatively, the patient is doing well with no recurrence of infection.

Abscess↗

PubMed2003

[Redo coronary artery bypass operation under beating heart via the left thoracotomy reusing patent grafts].

We report three cases of successful redo coronary artery bypass grafting (CABG) under beating heart via left thoracotomy with recycling of patent grafts previously implanted. Case 1 and 2: Anginal attack relapsed due to occlusion of the proximal portions of saphenous vein grafts (SVG) that had been sequentially anastomosed to the left coronary artery branches. In each case, the distal portion of the SVG was patent and functioned as coronary-coronary bypass. The left internal thoracic artery graft (ITAG) anastomosed to the left anterior descending coronary artery (LAD) was patent. Each patient underwent off-pump CABG through a left posterolateral thoracotomy. CABG was performed with the radial artery to the circumflex coronary artery (case 1) or the circumflex coronary artery and previous SVG (case 2). The proximal ends of radial artery grafts were anastomosed to the descending aorta. Case 3: Simultaneous reoperative CABG and the operation for the pseudoaneurysm that developed after the abdominal aortic graft replacement were performed. Bypass grafting between ITAG and LAD was performed with SVG via a left anterolateral thoracotomy because of severe anastomotic stricture of ITAG-LAD. The postoperative courses was uneventful for all patients.

Aged↗

PubMed2002

Proton energy spectra in the nonmesonic weak decay of 12lambdaC and 28lambdaSi hypernuclei.

Numbers of protons per Gamma hypernuclear weak decay were measured as a function of proton energy above 40 MeV, explicitly identifying production of Gamma hypernuclei by the (pi+,K+) reaction. The ratios between the neutron-stimulated to proton-stimulated nonmesonic decay widths, Gamma((Lambda)n-->nn)/Gamma((Lambda)p-->np) ( = Gamma(n)/Gamma(p)) were extracted by fitting the proton energy spectra. The present result claims that the proton yields are suppressed and the Gamma(n)/Gamma(p) ratios are close to 1 both for 12LambdaC and 28LambdaSi in contradiction to theoretical expectations based on meson exchange models.

Journal Article↗

PubMed2002

Liposome-mediated transfer of the bcl-2 gene results in neuroprotection after in vivo transient focal cerebral ischemia in an animal model.

Acute cerebral ischemia causes hypoxic neuronal cell death by necrosis and apoptosis. Expression of anti-apoptotic transgenes in ischemic brain may provide a useful therapeutic strategy for alleviation of postischemic damage. The present study investigates liposome-mediated transfer of the human bcl-2 protein in a rat model of focal transient ischemia due to middle cerebral artery (MCA) occlusion. Two different types of plasmid vectors were used for bcl-2 expression: one driven by the constitutive cytomegalovirus promoter (pCMV) and another based on the hypoxia-inducible human vascular endothelial growth factor promoter (pHRE). Cationic liposome/plasmid DNA complexes (lipoplexes) were injected directly into the cerebrospinal fluid (CSF) of rats immediately after MCA occlusion. The brains of treated and control animals were analyzed 48 h later. Infarct volumes and numbers of apoptotic cells were quantified. Occlusion of the MCA resulted in ipsilateral cerebral infarcts in all study animals. Transfer of the bcl-2 gene resulted in high level widespread protein expression in the case of the pCMV-bcl2 plasmid, while animals treated with the pHRE-bcl2 vector showed lower expression levels of bcl2 which were in addition limited to the ischemic area. Treatment with pCMV-bcl2, but not with pHRE-bcl2, was able to significantly reduce the infarct volume, which was 109 +/- 8 mm(3) for pCMV-bcl2, 152 +/- 29 mm(3) for pHRE-bcl2, and 155 +/- 18 mm(3) for control animals. Animals transfected with either vector showed a significant reduction in numbers of apoptotic cells in the infarct and penumbra area compared with controls. There were no short-term neurological side-effects of the CSF injection of lipoplexes or of bcl-2 expression. In conclusion, the hypoxia-inducible bcl-2 expression mediated by intrathecal lipoplexes may represent a novel, biologically safe and lesion-selective therapeutic approach for neuroprotection after acute cerebral ischemia. DOI: 10.1038/sj/gt/3301676

Acute Disease↗

PubMed2002

Treatment of habitual temporomandibular joint dislocation with miniplate eminoplasty: a report of nine cases.

Eminoplasty using T-shaped titanium miniplate was performed on 15 joints in nine patients suffering from recurrent dislocation of the temporomandibular joint with several general complications. After the conventional pre-auricular approach to the zygomatic arch and eminence, the bent over miniplate was inserted anteriorly against the articular eminence and fixed to the zygomatic arch with miniscrews to limit the over-movement of the condyle. In one case, the miniplate fractured, but no recurrence of dislocation was observed. In another case, it was possible to evaluate the mandibular movement by Sirognathograph analysis, which proved satisfactory function of the joints.

Aged↗

PubMed2002

Bone induction in subcutaneous tissue in rats by a newly developed DNA-coated atelocollagen and bone morphogenetic protein.

A unique biomaterial, a mixture of DNA and collagen (DNA/collagen), was developed and its efficacy as a carrier matrix for bone morphogenetic protein (BMP) was evaluated histologically. The material was prepared as a composite of DNA from salmon milt and pepsin-digested type I collagen (atelocollagen) from bovine dermis. Phase-contrast and fluorescence microscopy showed atelocollagen fibres with DNA coating. The dose-response and time-course of bone induction by BMP in DNA/collagen (5 x 10 x 1 mm) in the subcutaneous tissue was investigated in 20 male Wistar rats. The BMP/DNA/collagen induced new bone in a dose-dependent manner (0, 25, 50 or 100 micrograms of BMP). Histological examination in the time-course study showed that the BMP (100 micrograms)/DNA/collagen induced bone formation, while the DNA/collagen alone resulted in the accumulation of fibroblasts. These results indicate that the DNA/collagen is effective as a carrier matrix for BMP. It provides a cell anchorage for differentiation of osteoblasts and is absorbed as bone matures.

Absorbable Implants↗