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T Hirata

Publications and source records attributed to T Hirata.

At least 127 records · Page 7Linked to original sources
PubMed1998

Requirement for early-generated neurons recognized by monoclonal antibody lot1 in the formation of lateral olfactory tract.

During development, mitral cells, the main output neurons of the olfactory bulb, project axons into a very narrow part of the telencephalon and form an axonal bundle called the lateral olfactory tract (LOT). The present study shows that before the first mitral cell axons elongate, the LOT position is already marked with a subset of early-generated neurons that are recognized by monoclonal antibody lot1 (lot cells). Mitral cell axons choose the lot cell position for their growth pathway and maintain a close contact with the cells until LOT formation is completed. Ablation of lot cells prevented LOT formation in organotypic culture. These results suggest that lot cells are "guidepost cells" for mitral cell axons.

Animals↗
PubMed1998

Expression of CD44 variant exon 6 in stage I non-small cell lung carcinoma as a prognostic factor.

Specific CD44 isoforms are the surface adhesion molecules that have been shown to be associated with metastasis. In the present study, the role of the expression of standard and variant CD44 isoform (CD44s and CD44v6) as prognostic indicators in pathological stage I non-small cell lung carcinoma was investigated immunohistologically using monoclonal antibodies. The results showed that the expression of CD44v6 correlates with adverse prognosis in stage I non-small cell lung carcinoma but not CD44s. The 5-year survival rate of the patients with CD44v6-positive tumors was 50%, which was significantly lower than that of CD44v6-negative patients (88%; P = 0.001). The incidence of recurrent distant metastasis in the CD44v6-positive patients (45%; 9 of 20 patients) was significantly higher than that in the CD44v6-negative patients (20%; 10 of 49 patients; P = 0.038), suggesting the involvement of CD44v6 in hematogeneous metastasis of lung carcinoma. Although the incidence of the expression of CD44v6 in squamous cell carcinoma was significantly higher than that in adenocarcinoma, histological type was not a significant prognostic factor. No significant correlation was found between the expression of CD44v6 and lymphatic or vascular vessel invasion, although lymphatic vessel invasion was found to be an independent prognostic factor in the multivariate analysis. To investigate the relationship between the expression of CD44v6 and proliferative activity of tumor cells, the expression of proliferating cell nuclear antigen (PCNA) was examined. The expression of CD44v6 was more frequently observed in PCNA-positive patients than in PCNA-negative patients (P = 0.019), but the expression of PCNA was not a statistically significant prognostic indicator. The results of multivariate analysis by the Cox proportional hazards model showed that CD44v6 was an independent prognostic indicator. We concluded that the expression of CD44v6 is a useful prognostic factor in stage I non-small cell lung carcinoma.

Carcinoma, Non-Small-Cell Lung↗
PubMed1998

Expression of human placental-type 6-phosphofructo-2-kinase/fructose 2,6-bisphosphatase in various cells and cell lines.

The expression of the human placental-type 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase (HP2K) in various human cells and cell lines was investigated at the levels of transcription and translation. Analyses by both Northern blotting and a reverse transcription-polymerase chain reaction (RT-PCR) showed that BeWo, U-937, SupT1, H9, HeLa, HepG2, and human mononuclear cells, as well as human placental chorionic cells, expressed HP2K mRNA. All the nucleotide sequences of RT-PCR products from these cell lines were identical to that of HP2K. The expression of HP2K protein was determined by Western blot analysis of fractions from POROS-HQ column chromatography of the cell extracts from U-937 cells, which was used as an example of HP2K-mRNA positive cell lines. As with the 6-phosphofructo-2-kinase activity of HP2K, the activity of 6-phosphofructo-2-kinase in extracts of U-937 cells was not inhibited by glycerol 3-phosphate, a known 6-phosphofructo-2-kinase inhibitor of liver- and testis-type isozymes. These results strongly suggested that various cell lines, in particular U-937 cells, express functional HP2K enzyme. Furthermore, 6-phosphofructo-2-kinase in U-937 cells was found to be activated by treatments with isoproterenol and phorbol 12-myristate 13-acetate, indicating regulation of 6-phosphofructo-2-kinase activity in U-937 cells by protein kinases A and C.

Blotting, Northern↗
PubMed1998

Cardiovascular Effects of Bolus-Administered Vasodilators in Elderly Patients with Atherosclerotic Disease: A Comparative Study of Nitroglycerin and Prostaglandin E1

To evaluate the hemodynamic effects of vasodilators in elderly patients with atherosclerotic disease, systemic hemodynamics were examined during cardiac catheterization study. After the intravenous bolus injection of nitroglycerin (NTG, 5 µg/kg, n = 20) or prostaglandin E1 (PGE1, 0.2 µg/kg, n = 20), significant reduction of mean arterial pressure, pulmonary capillary wedge pressure (PCWP), systemic vascular resistance index (SVRI), and rate-pressure product (RPP) was observed. In contrast, cardiac index and stroke index were not significantly deteriorated in either group. In conclusion, bolus-administered NTG and PGE1 had beneficial vasodilating effects without harmful impact on cardiac functions in elder patients with atherosclerotic disease.

Journal Article↗
PubMed1998

Anticoagulant Effects of Argatroban on the Pre-DIC State in Patients with an Aortic Aneurysm: A Comparative Study of Heparin

We compared the efficacy of argatroban, a new synthetic thrombin-specific inhibitor, with that of heparin in pre-DIC state patients with abdominal aortic aneurysm (AAA). A pre-DIC state was diagnosed by a detection of soluble fibrin monomer complex (FM) and increased levels of thrombin-antithrombin III complex (TAT) of more than 20 ng/ml. Twelve patients showing a pre-DIC condition were treated with argatroban (40 mg/day, n = 6) or heparin (10,000 U/day, n = 6) for 5 days. Coagulation and fibrinolytic profiles were analyzed before and after drug administration. FM became negative in two (33%) patients after the argatroban treatment and in all (100%) of the heparin-treated patients. Plasma levels of TAT were significantly decreased after the heparin treatment, however, there was no significant alteration in this parameter after the argatroban treatment. In conclusion, the anticoagulant effects of heparin were superior to those of argatroban in controlling the pre-DIC state associated with AAA.

Journal Article↗
PubMed1998

[Cardiac hemangioma of the right ventricle--report of a case].

A 74-year-old male was admitted to our hospital with a diagnosis of intra-cardiac tumor on echochardiography, CT, and MRI. The tumor was located on the free wall of the right ventricle and protruded into the outflow tract. The surgical excision of the tumor was performed under cardiopulmonary bypass. The size of the tumor was 5 x 5 x 4 cm. Histological examination disclosed cavenous hemangioma. The post opertive course was uneventful. This is the forth case reported in Japan and the fifteenth case in the world.

Aged↗
PubMed1998

[A surgical case for concomitant coronary artery disease and ASO with advanced colon cancer].

We report a successful surgical case of concomitant severe coronary artery disease and ASO with advanced sigmoid colon cancer. This patient underwent two-stage operation. Resection of the sigmoid colon was carried out first, then CABG and aortofemoral bypass was carried out simultaneously. The surgical strategy of a patient with coronary artery disease and malignant neoplasm is still controvertial, however, it should be decided considering the severity and the symptoms of both disease. In this case, ascending aorta was used as a donor artery for aortofemoral bypass. This technique will bring those benefits, i.e., consecutive operation procedures in same operating field, obtaining abundant blood flow to lower limb and safe IABP catheter insertion from subcutaneously tunneled bypass graft.

Adenocarcinoma↗
PubMed1998

[Clinical benefits of normothermic cardiopulmonary bypass on postoperative systemic metabolism].

To evaluate the influence of body temperature during cardiopulmonary bypass (CPB) on postoperative systemic metabolism, 32 patients undergoing elective cardiac surgery were randomly assigned to either hypothermia (n = 16) or normothermia (n = 16). Serial hemodynamic parameters and blood samples were obtained after surgery. CPB and operation times were significantly shorter and the platelet reduction ratio during CPB [ = (platelets before CPB-platelets after CPB)/platelets before CPB] was significantly lower in normothermic patients than in hypothermic patients. The platelet reduction ratio was dependent on the minimum rectal temperature during CPB, the operation time, and the CPB time. In the early postoperative period, hypothermic patients had abnormally high systemic vascular resistance and a reduced cardiac index compared with the normothermic patients. There were no differences between 2 groups in postoperative hepatic and renal functions, changes in oxygen consumption, arterial-venous PCO2 or arterial-venous pH gradient. This study suggested a beneficial influence of normothermic CPB on postoperative hemodynamics. Normothermic CPB was not associated with adverse effects on postoperative metabolic recovery.

Aged↗
PubMed1998

When they grow up: the growth of extremely low birth weight (< or = 1000 gm) infants at adolescence.

The growth of 32 extremely low birth weight infants (1000 gm or less) was determined at adolescence. Their height, weight, and head circumference were measured twice in the first year of life and then at ages 2, 3, 5, 8, 10 years, and during adolescence (12 to 18 years). The mean height, weight, and head circumference of the adolescents were at the 50th percentile. Female heights were > or = their mothers; male heights were in the same or greater percentile than those of their fathers. Extremely low birth weight infants experience "catch-up" growth up to and into adolescence and attain predicted biparental genetic height.

Adolescent↗
PubMed1998

Anaplastic transformation of a papillary carcinoma of the thyroid in a patient with Graves' disease with varied activity of thyrotropin receptor antibodies.

We describe a 75-year-old man who had had a lump in his neck for about 15 years. At his first visit to our hospital, poorly differentiated papillary carcinoma of the thyroid was diagnosed by means of aspiration cytology; x-rays revealed the presence of lung metastases. He was thyrotoxic with positive thyroid stimulating antibody (TSAb). He was reluctant to undergo surgery. In an early stage of the treatment for Graves' disease, he became hypothyroid with decreased TSAb activity and strongly positive thyroid stimulation blocking antibody (TSBAb), and rapid growth of the thyroid carcinoma with anaplastic transformation was observed. The increase in the size of the transformed thyroid carcinoma was shown to be exponential by ultrasonography. This is a rare case in which anaplastic transformation of the thyroid papillary carcinoma became apparent during treatment of Graves' disease with varied activity of thyrotropin receptor antibodies.

Aged↗
PubMed1998

Magnetic resonance imaging of acute cerebellar ataxia: report of a case with gadolinium enhancement and review of the literature.

A 10-year-old girl exhibited severe cerebellar ataxia following acute enterocolitis, and was diagnosed as having acute cerebellar ataxia (ACA). MRI of the brain in the acute stage revealed moderate swelling of the cerebellum and abnormal signal intensity enhanced with gadolinium in the cerebellar hemisphere. This is the first report of an ACA case with positive gadolinium enhancement. Cases of ACA with MRI abnormalities are reviewed and the clinical entity of ACA is discussed in association with autoimmune encephalitis.

Acute Disease↗
PubMed1998

Abnormalities of electrocardiographic P wave morphology and their relation to electrophysiological parameters of the atrium in patients with sick sinus syndrome.

We examined the incidence of long P wave duration in lead II and increased P terminal force in lead V1 (PTFV1), and their relationship to electrophysiological findings of atrial muscle in 34 patients with sick sinus syndrome (SSS). Patients were divided into three groups: Group I, consisting of 20 patients with various cardiac arrhythmias other than SSS and paroxysmal atrial fibrillation (PAF) who served as controls; Group II, consisting of 18 patients with SSS but without PAF; and Group III consisted of 16 patients with SSS and PAF. P wave duration was significantly longer in Group III (122 +/- 11 ms, mean +/- SD, P < 0.0001) and Group II (111 +/- 15 ms, P < 0.002) than in Group I (98 +/- 10 ms). PTFV1 was greater in Group III (0.052 +/- 0.025 ms) than in Group I (0.028 +/- 0.011 ms, P < 0.05). P wave duration and PTFV1 had significantly and/or borderline correlations with longest duration of right atrial electrograms (r = 0.84, P < 0.0001 and 0.47, P < 0.02, respectively), maximal number of fragmented deflections of atrial electrograms (r = 0.69, P < 0.0001 and r = 0.51, P < 0.02, respectively), repetitive atrial firing zone (RAFZ) (r = 0.81, P < 0.0001 and 0.48, P < 0.05, respectively) and fragmented atrial activity zone (FAAZ)(r = 0.53, P < 0.01 and r = 0.45, P = 0.06, respectively). We concluded that long P wave duration and increased PTFV1 are electrocardiographic indicators for coexistence of electrophysiological abnormalities in the atria in SSS without recognizable heart disease.

Adult↗
PubMed1998

Long-term remission after brachytherapy with external irradiation for locally advanced lung cancer.

Three cases are reported who received brachytherapy with external irradiation for inoperable lung cancer and have shown long-term remission. The diseases were adenoid cystic carcinoma, recurrent adenocarcinoma and squamous cell carcinoma. The associated symptoms were severe cough and dyspnea in all 3 cases. They received 60 Gy of external irradiation. After an interval of 2 weeks, 6 Gy at a radius of 1 cm from the center of the source was delivered by iridium-192. They received 2-4 fractions at 1-week intervals. On termination of brachytherapy, complete response was observed in all cases. In 1 case, bronchial stenosis due to radiation-induced fibrosis was observed, but was successfully treated by bronchial stent. Cough and dyspnea disappeared, and all patients have been rendered asymptomatic for the last 2 years. Local disease was well controlled in 2 cases; however, minimal local recurrence was observed after a 2-year follow-up in 1 case.

Adenocarcinoma↗
PubMed1998

Screening of an inhibitor of the tetracycline efflux pump in a tetracycline-resistant clinical-isolate of Staphylococcus aureus 743.

Clinically-isolated methicillin-resistant Staphylococcus aureus (MRSA) strain 743 exhibited resistance to tetracycline as judged from the active efflux of the drug. The efflux of tetracycline was inhibited by an uncoupler, carbonyl cyanide m-chlorophenylhydrazone (CCCP), and minocycline. Inhibitors of the efflux pump were examined in this strain to determine the cellular accumulation of tetracycline. Out of seven compounds examined, three caused a significant increase in the cellular concentration of tetracycline by inhibiting the efflux pump. Two of them seem to be energy inhibitors. Ro 07-3149 inhibited the efflux pump without affecting the energy state, and exhibited very low antibacterial activity but showed weak synergy with tetracycline.

Anti-Bacterial Agents↗