Search PubMed⌕ Search

Biomedical subjects

T Yamada

Publications and source records attributed to T Yamada.

At least 307 records · Page 17Linked to original sources
PubMed2001

Diagnostic validity of computed tomography for mediastinitis after cardiac surgery.

BACKGROUND: Optimal treatment based on appropriate early diagnosis is essential in managing mediastinitis after cardiac surgery. We evaluated the accuracy of thoracic computerised tomography (CT) in the diagnosis of mediastinitis. METHODS: Forty-one patients in whom we performed CT after cardiac surgery were classified into two groups as follows; Six cases had mediastinitis requiring a redo surgical intervention (Group M). Thirty-five cases recovered without mediastinitis (Group C). Comparisons of CT findings in both groups were made retrospectively. RESULTS: In group M, CT and re-operations were performed 6.3+/-2.5 days and 8.0+/-5.2 days after previous operation, respectively. All but one of redo surgical procedures were mediastinal lavage and omental transplantation. Two patients died due to septic shock and multiple organ failure. CT in group M showed a soft tissue mass with contrast enhancement in 4 patients, bilateral pleural effusion in 5, free gas appearance in 4, and sternal dehiscence or destruction in 2 patients. Consequently, we regarded 4 of the 6 patients in this group as showing postoperative mediastinitis radiographically. In group C, CT performed 16.6+/-7.1 days after operations revealed findings suggestive of mediastinitis in 6 patients. Therefore, in terms of the validity of CT for the diagnosis of mediastinitis, the sensitivity was 67% and the specificity was 83%. CONCLUSION: The sensitivity of CT for diagnosis of mediastinitis after cardiac operations is unsatisfactory. Diagnosis by seeking infective changes in a multidisciplinary way is important in dealing with mediastinitis.

Aged↗
PubMed2001

Application of principal component analysis to the elucidation of perioral soft tissue movements during mastication.

We considered that elucidation of the movements of perioral soft tissue during mastication would be useful in evaluating masticatory movements. However, the evaluation of these movements is difficult because multivariable analysis is needed. In this study, we considered whether principal component analysis (PCA), a form of the multivariate analysis, can reduce the number of degrees of freedom (d.f.) of perioral skin movements (i.e. the time-series data with 45 d.f.). The subjects were 15 healthy persons with complete natural dentition. The chosen experimental food for this study was sufficiently softened chewing gum. Over 95% of the perioral soft tissue movements of healthy subjects with complete natural dentition during mastication could be expressed by PCA using the first three principal components (PCs). Therefore, perioral soft tissue movements in these subjects during mastication were considered to be spatially smooth. Moreover, time analysis of these movements was made possible by the application of proportion diagrams. The results of this study showed that the spatiostructural and temporal analyses of the movements of perioral soft tissue during mastication made possible by the application of PCA.

Adult↗
PubMed2001

Castration-induced expression of caspase-1 in epithelia of accessory sex organs in male rats.

AIM: As an attempt to clarify the molecular basis of castration-induced apoptosis, this study was undertaken to demonstrate the expression of caspase-1 in male accessory sex organs of rats. METHODS AND RESULTS: cDNA of rat caspase-1 was cloned by reverse transcription-polymerase chain reaction from the ventral prostates. The open reading frame predicts 402 amino acids, which shows more than 91% and 63% identity to those of mouse and human, respectively. Northern analyses demonstrated the presence of castration-induced up-regulation of the 1.6 kb transcript in the ventral prostate and the seminal vesicles. Finally, the authors demonstrated the caspase-1 transcripts in the epithelia of these tissues by in situ hybridization analyses. CONCLUSION: Castration induces the expression of caspase-1 transcripts in the epithelia of ventral prostate and seminal vesicle. These observations suggest a possible role of caspase-1 in apoptosis in male accessory sex organs.

Amino Acid Sequence↗
PubMed2001

Developmental morphology of ovules and seeds of Nymphaeales.

Ovule and seed development in six species of Nymphaeales was examined. In the Cabombaceae the two species studied resemble some extant basal angiosperms by having a hood-shaped outer integument. A micropyle-hilum complex results when the outer integument and derived testa are lacking between the micropyle and the funiculus, thus the hood-shaped appearance. In the Nymphaeaceae the outer integument is annular at an early stage and then cup-shaped though it is semiannular at initiation in Nupar japonicum and Nymphaea alba. The micropyle and hilum are separated by an intervening testa. Developmental data on the formation of the outer integument, from semiannular to hood-shaped vs. from annular to cup-shaped, are useful for inferring the morphology of the outer integument from the relative position of the micropyle to the hilum in seed fossils. The oldest (early Cretaceous) probable nymphaealean seeds had the micropyle-hilum complex, suggesting that the hood-shaped outer integument may be primitive in the Nymphaeales. This needs to be tested by examination of this feature in other groups of basal angiosperms.

Journal Article↗
PubMed2001

High-dose vitamin C therapy for inclusion body myositis.

OBJECTIVES: The efficiency of high-dose vitamin C therapy for inclusion body myositis (IBM) was assessed. SUBJECTS & METHODS: The subjects were five patients with IBM confirmed pathologically. After the intravenous administration of 40 mg/kg vitamin C five times/week for four weeks, muscle weakness was found to improve in three cases. The average muscle score improved from 8.1 to 8.8, from 7.0 to 8.1 and from 6.2 to 6.8. Magnetic resonance imaging (MRI) demonstrated a reduction in the size of T2 high lesions and gadolinium enhancement in the thigh muscles in one case. Based on our findings, high-dose vitamin C therapy is considered to be effective in some cases of IBM.

Aged↗
PubMed2001

[A case of paraneoplastic cerebellar degeneration with resting tremor].

A 65-year-old woman was operated for gastric adenocarcinoma in 1989. Six years later, peritonitis carcinomatosa, swelling of periaortic lymphnodes and high serum CA-125 were discovered. She received chemotherapy with 5-FU and cisplatin resulting in reduction of ascites. In September, 1998, the swelling of left supraclavicular lymphnodes and the elevation of serum CA-125 reappeared. Pathological diagnosis of supraclavicular lymphnodes was adenocarcinoma. Serum CA-125 was normalized by chemotherapy using cisplatin, farumorubicin and endoxan. However, unsteadiness appeared since December 10, 1998 followed by dysarthria and involuntary movement of neck and upper limbs. These symptoms progressed subacutely. The physical examination on admission revealed swelling of left suraclavicular lymphnodes, nystagmus on lateral gaze, saccadic eye movement on smooth pursuit and severe cerebellar ataxia. In addition, resting tremor of 3-4 Hz was observed at right hand, left wrist and neck which tended to increase amplitude by calculation. Similar movements were seen in the left first toe, though the frequency was lower. Brain MRI revealed mild cerebellar atrophy. She was diagnosed as paraneoplastic cerebellar degeneration (PCD) by serum anti Yo antibody and clinical course. The study of HLA showed positive link to A4 without A24. The primary focus of adenocarcinoma in cervical lymphnodes was suggested to be ovary rather than stomach due to the pattern of immunostaining for cytokeratin, CEA and CA125, although no carcinoma was found in ovarium clinically. The feature of this case is a PCD with resting tremor of frequency of 3-4 Hz and negative link to HLA-A24 in Japanese.

Adenocarcinoma↗
PubMed2001

[Relation between neck accessory inspiratory muscle electromyographic activity and lung volume].

Years ago it was reported that, as lung volume increased, there was a corresponding increase in scalene EMG activity (Raper et al. J Appl Physiol 21: 497-502, 1966). Otherwise, the relationship between changing lung volume and the EMG of the respiratory muscles has not been defined. We therefore inserted fine wire electrodes into the scalene (SCLN), sternocleidomastoid (STERNO), and trapezius (TRAPEZ) muscles in 6 healthy subjects under direct vision using high-resolution ultrasound. Maximum EMG activity (EMGmax) was obtained for each muscle by a variety of respiratory and postural maneuvers. Then, in the standing posture, air flow, raw and moving average EMG signals were sampled and input to a computer during quasi-static inspiration from functional residual capacity (FRC) to total lung capacity (TLC). We found that the relationship between EMG and lung volume for SCLN, but not for STERNO or TRAPEZ, was expressed by exponential curves. The onset of SCLN, STERNO and TRAPEZ EMG occurred at 13.3 +/- 7.4 (mean +/- SE), 67.8 +/- 14.6, and 89.2 +/- 3.9% of inspiratory capacity. The EMG of SCLN, STERNO, TRAPEZ, reached 85.7 +/- 2.6, 60.7 +/- 8.6, and 11.8 +/- 5.2% of EMGmax, respectively, at TLC. We conclude that: 1) SCLN is the most, and TRAPEZ the least, active neck accessory inspiratory muscle, while STERNO is intermediate, and 2) there is a lung volume dependency of the neck accessory muscle EMG activity.

Adult↗
PubMed2001

Influence of ethanol on metabolism of methamphetamine in rats including hair analysis.

To investigate possible influences of ethanol (EtOH) on metabolism of methamphetamine (MA), dark agouti (DA) rats were assigned to 3 groups including EtOH mono-dosing group, MA mono-dosing group and combined dosing group of EtOH and MA. Following successive administration of respective drugs, time-course changes of plasma and urine levels of EtOH and its metabolites, as well as alterations of plasma, urine, hair levels of the MA and its metabolites, were monitored. Preliminary hydrolysis of the glucuronate conjugates was required because parahydroxymethamphetamine (p-OHMA) and parahydroxyamphetamine (p-OHAP) were promptly conjugated with glucuronic acid in the body. When compared with EtOH group, the maximum plasma concentration of EtOH occurred with some delay in EtOH + MA group, suggesting possibility of some delay of its metabolism. MA concentrations in EtOH + MA group were slightly higher until 6 hours after administration when EtOH was detectable in the blood whereas concentrations of amphetamine (AP) in EtOH + MA group were less, on the contrary. Concentrations of p-OHMA and p-OHAP were obviously less in EtOH + MA group. These findings indicate that N-demethylation and parahydroxylation of aromatic ring of MA would be inhibited in the presence of EtOH. Concentrations of MA and AP in hair were higher in EtOH + MA group. Not only difference in AUC but also possible increase in uptake of the drugs into hair could likely account for this phenomenon.

Amphetamine↗
PubMed2001

Studies on mechanisms of low emetogenicity of YM976, a novel phosphodiesterase type 4 inhibitor.

YM976 is a novel and selective inhibitor of phosphodiesterase type 4 (PDE4) with a different chemical structure from rolipram. Orally administered YM976 showed anti-inflammatory activity (ED(50) = 2.8 mg/kg) similar to rolipram (3.5 mg/kg). On the other hand, the emetogenicity of YM976, one of the main adverse effects of PDE4 inhibitors, was lower (maximal non-emetic dose = 10 mg/kg) than that of rolipram (1 mg/kg). The reasons for this low emetogenicity of YM976 remain unclear, and the present study endeavored to elucidate the mechanisms. Candidates for the possible mechanisms included 1) PDE4 subtype selectivity, 2) binding affinity for HAR-conformation, and 3) brain penetration. YM976 exhibited affinity for high affinity for rolipram-conformation (HAR-conformation) (IC(50) = 2.6 nM) identical to that of rolipram (1.2 nM), and failed to show significant selectivity for the individual PDE4 subtype. These results suggested that neither subtype selectivity nor the affinity for HAR-conformation may be related to the low emetogenicity of YM976. YM976 showed a minor effect on reserpine-induced hypothermia, in contrast to rolipram. To estimate brain penetration, we then measured cAMP contents in peripheral tissues (peritoneal macrophages) and in the brain. YM976 increased the cAMP content of peritoneal macrophages, but caused no significant increase in brain cAMP levels, while rolipram elevated the cAMP content of both tissues at the same dose. In conclusion, YM976 shows an apparent dissociation between its anti-inflammatory effects and emetogenicity, perhaps because of the poor brain penetration.

3',5'-Cyclic-AMP Phosphodiesterases↗
PubMed2001

[Diffuse large B-cell lymphoma expressing cytoplasmic IgM and kappa in a patient with lambda-type primary macroglobulinemia].

A 69-year-old woman who had had lambda-type primary macroglobulinemia (PMG) since December 1993 was admitted in October 1997 because of obstructive jaundice due to compression of the common bile duct by a retroperitoneal tumor. A biopsy sample was obtained by exploratory laparotomy, and from this a diagnosis of diffuse large cell lymphoma (DLCL) expressing cytoplasmic IgM/kappa was made. Partial remission was obtained after 6 courses of combination chemotherapy consisting of pirarubicin, cyclophosphamide, vincristine and prednisolone. However, the DLCL was generally progressive, and the patient died in August 1998 due to multiple organ failure. There was no difference in the plasma monoclonal IgM/lambda level before and during the course of DLCL. The clone of the DLCL may have been different from that of the PMG.

Aged↗
PubMed2001

Rupture of the spleen as an unusual complication of laparoscopy. A case report.

BACKGROUND: Laparoscopic surgery has many advantages but is not without complications, such as viscus perforation and intraabdominal hemorrhage. CASE: A rare and severe complication, massive abdominal bleeding due to splenic rupture, became symptomatic after an uneventful laparoscopy. Tearing away of delicate peritoneal reflections or small adhesions on the splenic capsule due to induction of pneumoperitoneum can result in sudden rupture and hemorrhage. CONCLUSION: This possibility should be remembered when laparoscopy is necessary in patients with a history of blunt abdominal trauma.

Abdominal Injuries↗
PubMed2001

Large-scale selection of lines with deletions in chromosome 1 B in wheat and applications for fine deletion mapping.

Terminal deletions of chromosome 1B in common wheat were selected on a large scale. The gametocidal gene of Aegilops cylindrica was used as the inducer of chromosome breakage. First, genes for endosperm storage proteins located on both arms of chromosome 1B were used as the selection markers. However, it was found that the chromosome breakage occurred during female gametogenesis, causing genotypic inconsistency between the embryo and endosperm. Thus, we isolated plants with terminal deletions in chromosome 1B by C-banding. Of 1327 plants examined, 128 showed aberrations in chromosome 1B: 47 in the short arm, 76 in the long arm, and 5 in both arms. The present deletions tended to have the breakpoint at more proximal regions than those produced previously by T.R. Endo and B.S. Gill. Using 33 deletion lines produced in this study and 34 lines previously produced, we mapped 39 RFLP loci and a nucleolar organizer region (NOR) on a specific region of chromosome 1B. The NOR was found to consist of two subregions with different repetitive units, which were termed NOR-Bld and NOR-Blp. Based on this fine deletion map and genotypic inconsistency between embryo and endosperm, the features of the gametocidal gene are discussed.

Chromosome Aberrations↗
PubMed2001

Evaluation of angiogenesis in non-small cell lung cancer: comparison between anti-CD34 antibody and anti-CD105 antibody.

PURPOSE: Angiogenesis is an essential process in the progression of malignant tumors. Whereas pan-endothelial markers, such as CD34, are generally used in evaluation of angiogenesis, pan-endothelial antibodies react with not only "newly forming" vessels but also normal vessels just trapped within tumor tissues. It has been recently reported that anti-CD105 antibody preferentially reacts with "activated" endothelial cells in angiogenic tissues. Thus, the superiority of anti-CD105 monoclonal antibody (mAb) in evaluation of angiogenesis of non-small cell lung cancer (NSCLC) was assessed. EXPERIMENTAL DESIGN: A total of 236 patients with resected NSCLC were retrospectively reviewed. Intratumoral microvessel density (IMVD) was determined with an anti-CD34 mAb (CD34-IMVD) and with an anti-CD105 mAb (CD105-IMVD). RESULTS: The mean CD34-IMVD and CD105-IMVD were 179.9 and 41.6, respectively. Whereas CD34-IMVD was significantly correlated with the expression of vascular endothelial growth factor (P = 0.003), CD105-IMVD was more closely correlated with vascular endothelial growth factor expression (P < 0.001). The 5-year survival rate of the lower CD105-IMVD patients was 74.9%, significantly higher than that of the higher CD105-IMD patients (60.4%, P = 0.018). Whereas the 5-year survival rate of the lower CD34-IMVD patients seemed higher than that of the higher CD34-IMVD patients (63.7%), the difference did not reach a statistical significance (P = 0.137). Multivariate analysis confirmed that higher CD105-IMVD was a significant factor to predict poor prognosis (P = 0.029), whereas CD34-IMVD was not (P = 0.070). CONCLUSIONS: Anti-CD105 mAb proved to be superior to anti-CD34 mAb in evaluation of angiogenesis in NSCLC.

Aged↗
PubMed2001

1H-NMR studies of the intracellular water of skeletal muscle fibers under various physiological conditions.

Intracellular water of frog skeletal muscle fibers has been studied under various physiological conditions by use of the 1H-nuclear magnetic resonance (NMR) technique. 1H-NMR spectra of muscle fibers had single peaks derived from the intracellular water. The spectra changed in a characteristic fashion when the fiber axis was aligned at various angles relative to the magnetic field of the NMR magnet. Further, the relaxation rates of the 1H-NMR spectra changed depending on the water content of muscle fibers, and in association with contraction and rigor formation of muscle fibers. The obtained results indicate that the intracellular water of muscle fibers is structured and aligned along the myofilaments, and further that the state of the intracellular water changes with physiological conditions.

Animals↗
PubMed2001

[A case of postoperative gastric cancer responding to adjuvant chemotherapy with TS-1--a novel oral formation of 5-fluorouracil].

TS-1 is a novel oral formation of 5-fluorouracil, developed using tegafur and two biochemical modulations. We report the case of a patient with multiple lymph node metastases from gastric cancer that markedly responded to TS-1. A 70-year-old man suffering from hematemesis was admitted to our hospital. Computed tomography showed advanced gastric cancer with huge lymph node metastases. After non-curative operation, he received adjuvant chemotherapy with TS-1 for 12 weeks. CT revealed that almost complete reduction of the metastatic nodes was obtained. No serious adverse reactions were observed.

Aged↗
PubMed2001

[A complete response persisting for twelve months with the use of TS-1 in a patient with paraaortic lymph node metastasis of gastric cancer].

A 74-year-old female patient underwent total gastrectomy, splenectomy and D2 lymph node dissection for gastric cancer with non-dissectible paraaortic lymph node metastasis. Pathological examination revealed a high level of metastasis of dissected lymph nodes. The patient received daily oral administration of 100 mg TS-1, a novel oral anticancer agent. Each treatment course consisted of a four-week administration followed by two drug-free weeks. A partial response was obtained after the second course and a complete response was observed in the middle of the fourth and after the sixth course. The treatment was stopped because of grade 2 anemia in the middle of the seventh course, but no other adverse effect was observed. Complete response of the treatment persisted for twelve months and the patient has now been in good health without a recurrence for twenty months after surgery. Although the prognosis of gastric cancer with a high level of lymph node metastasis is poor, TS-1 therapy may have a potent efficacy in gastric cancer patients with a high level of lymph node metastasis such as the current case.

Aged↗