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T Sakamoto

Publications and source records attributed to T Sakamoto.

At least 1,405 records · Page 78Linked to original sources
PubMedDate not supplied

Platelet hyperaggregability persists even after the improvement of increased blood coagulation and impaired fibrinolysis with the stabilization of symptoms in patients with unstable angina.

BACKGROUND: Platelet aggregation, blood coagulation, and fibrinolysis play a pivotal role in the pathogenesis of unstable angina. METHODS: Platelet aggregability was examined on admission and after 2 weeks of treatment in 22 patients with unstable angina, in particular with regard to small-sized platelet aggregates, plasma tissue factor (TF) antigen levels as a marker of blood coagulation, and plasma plasminogen activator inhibitor (PAI) activity levels as an indicator of fibrinolysis. We also examined the same parameters in 19 patients with stable exertional angina and 17 patients with chest pain syndrome. RESULTS: The number of small-sized platelet aggregates increased more significantly in the unstable angina group than in the stable exertional angina and chest pain syndrome groups. In the unstable angina group, the number of small-sized platelet aggregates decreased significantly after 2 weeks of treatment, but was still higher than that in the stable exertional angina and chest pain syndrome groups. Plasma TF antigen and PAI activity were higher in the unstable angina group than in the stable exertional angina and chest pain syndrome groups. TF and PAI activity decreased to normal ranges after 2 weeks of treatment in the unstable angina group. There were significant positive correlations among the three parameters on admission. CONCLUSIONS: It was demonstrated that small-sized platelet aggregates, plasma TF antigen and PAI activity levels increased concomitantly in the unstable angina group. While the blood coagulation and fibrinolytic parameters decreased after stabilization of the clinical symptoms, platelet hyperaggregability still persisted. These results suggest that continuous antiplatelet therapy is essential for the treatment of unstable angina.

Adult↗
PubMedDate not supplied

Relationship between mitral regurgitation and left ventricular outflow obstruction in hypertrophic cardiomyopathy.

To clarify the relationship between mitral regurgitation and left ventricular outflow obstruction, Doppler and two-dimensional echocardiographic studies were performed in 62 patients with hypertrophic cardiomyopathy (22 with and 40 without obstruction caused by mitral systolic anterior motion with septal contact). Pulsed Doppler echocardiography with color Doppler flow imaging demostrated that in 20 of the 22 patients with obstruction, mitral regurgitation occurred mainly during midsystole from the onset to the end of mitral-septal contact. Such midsystolic mitral regurgitation was not observed in patients without obstruction, except in three of 25 patients with mild mitral systolic anterior motion without septal contact. Furthermore, that regurgitation developed or disappeared together with the obstruction during follow-up periods or pharmacologic interventions. Two-dimensional echocardiography showed that in 21 of the 22 patients with obstruction, a distal residual portion of the "anterior" mitral leaflet moved anteriorly in early systole and protruded into the outflow tract during midsystole to cause the obstruction. In the other patient with obstruction, who had only early systolic mitral regurgitation, a distal residual "posterior" leaflet moved similary. These results may indicate that the midsystolic mitral regurgitation is hydrodynamically induced by the midsystolic pressure gradient across the protruding distal residual anterior mitral leaflet.

Adult↗
PubMedDate not supplied

Severe central fracture-dislocation of the hip migrated deep into the pelvis complicating ileal rupture and ipsilateral comminuted femoral fracture: CT characteristics.

A case of severe central fracture-dislocation of the hip migrated deep into the pelvis complicating ileal rupture and ipsilateral comminuted fracture of the proximal femur was described. Plain CT images of the pelvis were distinctive and quite useful for evaluating the severity of the injury. Osteomyelitis of the proximal femur occurred soon after resection of the femoral head and suturing of the peritoneum though laparotomy. Complete closure of the peritoneal laceration and rapid totally diverting colostomy would be recommendable in order to avoid infectious complications in such a severe central fracture-dislocation of the hip.

Abdominal Pain↗
PubMedDate not supplied

The combined effect against colon-26 cells of heat treatment and immunization with heat treated colon-26 tumour cell extract.

Cancer vaccines represent a promising new strategy for immunotherapy against cancer, but their effects are insufficiently understood. The effect of heat treatment against mouse colon adenocarcinoma cell line (colon-26), and combined effects of heat treatment and immunizing host animals with heat treated colon-26 cell extracts were investigated. Heat treatment of colon-26 cells induced heat-shock protein 70 (HSP70), but not other HSP. Immunization of BALB/cJ mice with heat treated colon-26 cell extract, which was enriched in HSP70, elicited antitumour immunity against subcutaneously injected colon-26 cells. Furthermore, combination therapy of heat treatment and immunization with heat treated colon-26 cell extract significantly reduced tumour volumes compared with heat treatment alone. Similar immunization enhanced the cytotoxic activity of mouse splenic lymphocytes against untreated and heat treated colon-26 cells in an in vitro assay, as well as against heat treated allogenic mouse lymphoma cell line (YAC-1). These findings suggest possible usefulness of heat treated cancer cell extract as a cancer vaccine, especially if given in combination with hyperthermia.

Adenocarcinoma↗
PubMedDate not supplied

Hair analysis for drugs of abuse XII. Determination of PCP and its major metabolites, PCHP and PPC, in rat hair after administration of PCP.

We developed an analytical method for the simultaneous detection of phencyclidine (PCP) and its metabolites, 4-phenyl-4-piperidinocyclohexanol (PPC) and 1-(1-phenylcyclohexyl)-4-hydroxypiperidine (PCHP), in rat hair. Three pigmented, hairy rats were intraperitoneally administered PCP hydrochloride (HCl) at 0.05-0.5 mg/kg once a day for 10 successive days. Animal hair was shaved just before the first administration, and the newly grown hair was collected 4 weeks after the first administration. After the rat hair sample was washed three times with 0.1% sodium dodecyl sulfonate and water, separately, and dried in a desiccator, 20 mg of finely cut hair was extracted with 2 mL methanol-5N HCl (20:1) under ultrasonication for 1 h, followed by storage at room temperature for 14 h. Following filtration and evaporation of the extract, it was purified with Bond Elut Certify in the usual manner, and the extract was derivatized with N,O-bis(trimethylsilyl) acetamide for gas chromatographic-mass spectrometric analysis using deuterated PCP, PPC, and PCHP as internal standards. The selected ions were monitored at m/z 186, 200, and 242 for PCP, m/z 172, 288, and 331 for trimethylsilyl (TMS) PCHP, and m/z 200, 254, and 331 for TMS PPC. PCP, PCHP, and PPC were simultaneously detected in the rat hair down to 0.1 mg/kg PCP HCl. Even at the dose of 0.05 mg/kg, PCP was clearly detected in the rat hair. Based on the area under the concentration versus time curve (AUC) in plasma (1460 ng.min/mL), the PCP concentration (3.34 ng/mg) in the rat hair was quite high. The incorporation rates into hair (concentration in hair/AUC) of PCP, PCHP, and trans-PPC were 2.29, 1.65, and 0.50, respectively, at 0.5 mg/kg. Our results suggest that hair could be a useful specimen for confirmation of active past PCP use because PCP and its metabolites can be detected simultaneously.

Animals↗
PubMedDate not supplied

Quantitative trait loci for spawning date and body weight in rainbow trout: testing for conserved effects across ancestrally duplicated chromosomes.

We incorporated 69 microsatellite loci into an existing data set of 132 markers to test for quantitative trait loci (QTLs) affecting spawning date and body weight in a backcross between two outbred strains of rainbow trout (Oncorhynchus mykiss). Twenty-six linkage groups were identified and synteny of duplicated microsatellite markers was used to confirm 13 homeologous chromosome pairs. Gene-centromere data were used to localize the centromeres for 13 linkage groups whose orientations were previously unknown. We applied a combination of interval mapping and single marker analysis to the segregating maternal and paternal alleles at 201 microsatellite loci. Four spawning date QTLs with suggestive evidence for an additional two QTLs were detected in female trout spawning at 3 and 4 years of age. Similarly we detected three QTLs for body weight in females at 2 years of age plus four suggestive QTLs for this trait. We found marginal evidence that three pairs of ancestral homeologues contained detectable QTLs for the same trait. In one of the three pairs of homeologues, the duplicated QTL regions mapped to the same relative chromosomal location, while the exact localization of the QTL position in one of the other pairs was difficult to infer since it was based on data from a male-derived map. The existing data were unable to refute a hypothesis that duplicated functional genes will be maintained within the telomeric regions of salmonids due to preferential male-mediated crossing over in this region. Two of the four spawning date QTLs were detected on linkage groups with unknown homeologous relationships. QTLs with possible pleiotropic effects on both spawning date and body size were localized to two linkage groups.

Animals↗
PubMedDate not supplied

Effects of timing on ventriculoarterial coupling and mechanical efficiency during intraaortic balloon pumping.

To evaluate the effects of deflation timing of an intraaortic balloon (IAB) on ventriculoarterial (VA) coupling and left ventricular (LV) mechanics, we assessed contractility: Emax (mmHg/ml); VA coupling: Ea/Ees; myocardial oxygen consumption: LV pressure-volume area (PVA); and energy efficiency: external work (EW)/PVA during IAB pumping, using four different timing intervals of IAB deflation in eight dogs weighing 19.8 +/- 3.8 kg. In the conventional timing group (G-conv), the IAB was deflated before LV systole. In the real time group (G-1, 2, 3), the IAB was deflated during isovolumic contraction (ICP), and the group was subdivided into three groups based on time of deflation: G-1 at the onset of ICP, G-2 at the midpoint of ICP, and G-3 at the end of ICP. Percent changes in values with IAB compared to those without assist were calculated. Based on the results, IAB deflation during ICP reduces LV end-systolic pressure and significantly optimizes VA coupling and LV efficiency during IAB support, compared with conventional timing.

Animals↗
PubMedDate not supplied

The contusion index: a reappraisal in human and experimental non-missile head injury.

A previously described method of quantifying cerebral contusions in man (the contusion index) caused by non-missile head injury has been modified and applied to a larger series of cases, and used to assess contusions in experimental head injuries. The initial findings in man have been confirmed, viz. that contusions are most severe in the frontal and temporal lobes; that contusions may be entirely absent in a patient dying as a result of a head injury; that there is no correlation between the severity of contusions and the nature of the injury; that the concept of contrecoup must continue to be questioned; that contusions are more severe in patients who have a fracture of the skull in comparison to those who do not; that contusions are more severe in patients who do not experience a lucid interval than in those who do; and that contusions are less severe in patients with diffuse axonal injury than in those who do not have diffuse axonal injury. The distribution of contusions in subhuman primates is similar to that seen in man, and they occur more frequently with short duration than with long duration acceleration.

Adolescent↗
PubMedDate not supplied

Comparison of in vitro antifungal activity of itraconazole and hydroxy-itraconazole by colorimetric MTT assay.

The in vitro antifungal activities of itraconazole and its active hydroxyl metabolite, hydroxy-itraconazole (R 63372), against Aspergillus fumigatus, Candida albicans and Cryptococcus neoformans were compared by visual assessment of growth as well as by colorimetric MTT [3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H tetrazolium bromide] assay using microtitre plates containing four different media. Minimum inhibitory concentration (MIC) end points determined by the colorimetric MTT assay correlated well with those obtained by visual assay. The two drugs showed different MIC values depending on the medium used. The activity of itraconazole was equal to or greater than the activity of hydroxy-itraconazole against most of the fungi tested. Both drugs showed lower MIC values against A. fumigatus and Cr. neoformans in brain heart infusion broth (BHI) medium than in yeast nitrogen base (YNBG) medium, Sabouraud glucose broth (SAB) or "synthetic amino acid medium, fungal" (SAAMF). However, the MIC end point of these drugs against C. albicans in BHI and SAB media was difficult to determine visually as well as by MTT assay. In C. albicans, the MTT assay method using SAAMF and YNBG media is recommended for the determination of MICs.

Antifungal Agents↗
PubMedDate not supplied

Helical CT in the diagnosis of small bowel obstruction.

With recent technologic developments, the role of computed tomography (CT) in the diagnosis of bowel obstruction has expanded. CT is recommended when clinical and initial radiographic findings remain indeterminate or strangulation is suspected. This modality clearly demonstrates pathologic processes involving the bowel wall as well as the mesentery, mesenteric vessels, and peritoneal cavity. CT should be performed with intravenous injection of contrast material, and use of thin sections is recommended to evaluate a particular region of interest. CT is reported to have a sensitivity of 78%-100% for the detection of complete or high-grade small bowel obstruction but may not allow accurate diagnosis in cases involving incomplete obstruction. In such cases, the use of adjunct enteroclysis is indicated. Furthermore, multiplanar reformatted imaging may help identify the site, level, and cause of obstruction when axial CT findings are indeterminate. CT can also demonstrate findings that indicate the presence of closed-loop obstruction or strangulation, both of which necessitate emergency exploratory laparotomy. Unfortunately, these pathologic conditions may be missed, and patients with suspected severe obstruction or bowel ischemia in whom CT and clinical findings are widely disparate must also undergo laparotomy. In general, however, CT allows appropriate and timely management of these emergency cases.

Diagnosis, Differential↗
PubMedDate not supplied

Intrahepatic metastasis by orthotopic implantation of a fragment of murine hepatoma and its related molecules.

Intrahepatic metastasis is a major modality in the recurrence of hepatoma. Establishment of the intrahepatic metastasis model would be useful for evaluating new anticancer therapies and analyzing the molecular mechanisms of tumor metastasis. Orthotopic implantation of a fragment of CBO140C12 hepatoma into the liver resulted in the formation of a solitary tumor nodule and its intrahepatic metastasis. In contrast, implantation of ADras3 cancer cells did not show any metastasis on day 21. CBO140C12 cells showed enhancement of the invasive, adhesive and migratory capabilities, as compared with ADras3 cells. Furthermore, mRNA expression and gelatinolytic activity of MMP-9 were detected in CBO140C12 cells, and the expression of mRNA for MT1-MMP in CBO140C12 cells was greater than that in ADras3 cells. Thus, intrahepatic metastasis of CBO140C12 tumor might be involved in the enhancement of the invasiveness of tumor cells via marked expression of MMP-9 and MT1-MMP.

Animals↗
PubMedDate not supplied

Analysis of epitopes of mouse monoclonal antibodies against human alpha-fetoprotein.

Thirty-six monoclonal antibodies (MAbs) against human alpha-fetoprotein (AFP) were analyzed for the location of their epitopes by reacting them with a set of yeast recombinant AFP proteins using ELISA. Recombinant AFP proteins containing either one, two or all three domains, i.e. domain I, domain III, domain I-II, domain II-III and domain I-II-III, were produced and secreted into the culture medium of yeast cells harboring the expression plasmids. Epitopes of 13 MAbs were localized on domain I and 17 others were on domain III. However, the exact location of the epitopes of the remaining 6 MAbs could not be defined. The epitope of an antibody, namely AFY6, which was located in domain I, was successfully mapped on an octapeptide, C175KAENAVE182, using synthesized overlapping octapeptides.

Animals↗