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T Hirano

Publications and source records attributed to T Hirano.

At least 145 records · Page 8Linked to original sources
PubMed2001

Wistar strain rats as the model for IgE antibody experiments.

The amount of plasma IgE antibody formed and its change over time were investigated by enzyme-linked immunosorbent assay (ELISA) in male and female Sprague-Dawley (SD), Donryu, and Wistar strain rats. IgE antibody formation was initiated by injecting a mixture of 2,4-dinitrophenylated ascaris extract (DNP-As) as antigen and killed Bordetella pertussis as adjuvant into the paws of the animals. The amount of IgE antibody formed was low on day 10 in both male and female SD (40-80 ng/ml) and Donryu (20-40 ng/ml) strain rats, and an increase in the amount was observed on day 20. The peak value of IgE antibody was observed day 10 in Wistar strain rats and was 130 and 200 ng/ml in the male and female rats, respectively. These results suggest that Wistar strain rats produce the most IgE antibody when DNP-As is used as antigen and they can serve as a model for allergic diseases.

2,4-Dinitrophenol↗
PubMed2001

Antioxidative and 5-lipoxygenase inhibiting activities of novel bis(4-hydroxy-2,3,5-trimethylphenoxy)alkyl derivatives.

Novel bis(4-hydroxy-2,3,5-trimethylphenoxy)alkyl derivatives were synthesized and evaluations were made of their inhibiting action on Fe3+-ADP induced lipid peroxidation in rat liver microsome and reducing action on alpha,alpha-diphenyl-beta-picrilhydrazyl (DPPH), a stable radical, in addition to their inhibiting action on 5-lipoxygenase (5-LO), an enzyme that synthesizes leukotrienes. We performed a structure-activity correlation study on these derivatives. A strong Fe3+-ADP induced lipid peroxidation preventing activity was observed for the derivatives with an odd number of methylene groups including 1,3-bis(4-hydroxy-2,3,5-trimethylphenoxy)propane (3b) and 3a. No change in the DPPH reducing activity was found with change in the number of methylene groups. 5-LO inhibiting activity among the derivatives was the highest for 1,6-bis(4-hydroxy-2,3,5-trimethylphenoxy)hexane (3e). MM2 calculations were performed to find a stable steric structure for the derivatives, and 1,5-bis(4-hydroxy-2,3,5-trimethylphenoxy)pentane (3d) showed a strong activity in both antioxidative action and 5-LO inhibiting action.

Animals↗
PubMed2001

Synthesis and physiological activity of novel tocopheryl glycosides.

Vitamin E glycosides were synthesized and enzymatic hydrolysis was examined for use as potential pro-drugs, however, the glycoside bond was found to be stable. On the other hand, among the glycosides synthesized, dl-alpha-tocopherylglucoside (6b) and dl-alpha-tocopherylmannoside (6c) showed strong inhibitory action on histamine release from mast cells. In addition, 6c also showed a suppressive action on IgE antibody formation. Thus, tocopheryl glycoside showed new properties compared to tocopherol (vitamin E). In particular, 6c was shown to be a novel lead compound with excellent manifold anti-allergic activity and anti-inflammatory activity.

Animals↗
PubMed2001

Sequence specificity of the 8-hydroxyguanine repair activity in rat organs.

The base excision repair system for 8-hydroxyguanine (8-OH-Gua) is believed to play a role in the prevention of mutations, such as GC-to-TA transversion, which leads to cancer development. However, the exact repair mechanism is still unclear. In this study, we examine whether the repair activity level for 8-hydroxyguanine, one of the major forms of oxidative DNA damage, depends on the sequence of the substrate DNA. We prepared six different oligonucleotides containing 8-hydroxyguanine as substrates and reacted them with crude extracts from the livers and kidneys of 8-week-old Sprague-Dawley rats. As a result, up to a 10-fold difference in the repair activity levels was observed, depending on the substrates used. Based on this observation, we suggest that the repair systems may act with sequence specificity on the damaged DNA.

Animals↗
PubMed2001

Intermittently administered human parathyroid hormone(1-34) treatment increases intracortical bone turnover and porosity without reducing bone strength in the humerus of ovariectomized cynomolgus monkeys.

Cortical porosity in patients with hyperparathyroidism has raised the concern that intermittent parathyroid hormone (PTH) given to treat osteoporotic patients may weaken cortical bone by increasing its porosity. We hypothesized that treatment of ovariectomized (OVX) cynomolgus monkeys for up to 18 months with recombinant human PTH(1-34) [hPTH(1-34)] LY333334 would significantly increase porosity in the midshaft of the humerus but would not have a significant effect on the strength or stiffness of the humerus. We also hypothesized that withdrawal of PTH for 6 months after a 12-month treatment period would return porosity to control OVX values. OVX female cynomolgus monkeys were given once daily subcutaneous (sc) injections of recombinant hPTH(1-34) LY333334 at 1.0 microg/kg (PTH1), 5.0 microg/kg (PTH5), or 0.1 ml/kg per day of phosphate-buffered saline (OVX). Sham OVX animals (sham) were also given vehicle. After 12 months, PTH treatment was withdrawn from half of the monkeys in each treatment group (PTH1-W and PTH5-W), and they were treated for the remaining 6 months with vehicle. Double calcein labels were given before death at 18 months. After death, static and dynamic histomorphometric measurements were made intracortically and on periosteal and endocortical surfaces of sections from the middiaphysis of the left humerus. Bone mechanical properties were measured in the right humeral middiaphysis. PTH dose dependently increased intracortical porosity. However, the increased porosity did not have a significant detrimental effect on the mechanical properties of the bone. Most porosity was concentrated near the endocortical surface where its mechanical effect is small. In PTH5 monkeys, cortical area (Ct.Ar) and cortical thickness (Ct.Th) increased because of a significantly increased endocortical mineralizing surface. After withdrawal of treatment, porosity in PTH1-W animals declined to sham values, but porosity in PTH5-W animals remained significantly elevated compared with OVX and sham. We conclude that intermittently administered PTH(1-34) increases intracortical porosity in a dose-dependent manner but does not reduce the strength or stiffness of cortical bone.

Animals↗
PubMed2001

Clinical investigation of the lesions responsible for sensory disturbance in Minamata disease.

To clarify the lesions responsible for sensory disturbance in Minamata disease (MD), we clinically investigated the characteristics of sensory disturbance. In all patients with the classical type MD, two-point discrimination was severely disturbed, but the involvement of superficial sensation was relatively mild. On short-latency somatosensory evoked potential study, the component corresponding to N20 was completely absent with normal N9, N11, and N13 components. Although 14 of 38 chronic MD patients demonstrated intact superficial sensation, 10 of these 14 showed mild to moderate disturbance in two-point discrimination. The two-point discrimination in chronic MD patients was significantly high irrespective of the disturbance of superficial sensation. These findings suggest that the sensory disturbance of MD patients may mainly be caused by a lesion in the sensory cortex rather than in the peripheral nerves. However, other foci could be also responsible for the sensory impairment, since 9 of 38 chronic MD patients showed intact two-point discrimination.

Adult↗
PubMed2001

K-ras mutation in sputum of primary lung cancer patients does not always reflect that of cancerous cells.

K-ras mutation in sputum was examined using mutant-allele-specific amplification method among 100 primary lung cancer and 15 non-oncological patients. K-ras mutation was detected in 11 out of 59 adenocarcinoma cases (18.6%), 5 out of 32 squamous cell carcinoma cases (15.6%), 2 out of 4 large cell carcinoma cases (50.0%) and 3 out of 15 non-oncological disease cases (20.0%). In the 18 cases of primary lung cancer K-ras mutation was examined in both sputum and the resected specimen of the primary lesion. In 5 cases K-ras mutation in sputum was detected without K-ras mutation in primary lesion. Therefore, these findings suggested that K-ras mutation in sputum may not be directly related to that of the primary lesion.

Adult↗
PubMed2001

[Teratoma in the cerebellar hemisphere of an infant].

We report here a 4-month-old male infant with a cerebellar teratoma. After vomiting for 5 days, he had a tonic-clonic seizure on the left showing secondary generalization. Neuroimaging studies showed severe hydrocephalus and a large tumor in the left cerebellar hemisphere, which showed calcification. Postictal scalp electroencephalogram showed right hemispheric spikes and spike-waves. He underwent an emergency operation and had the tumor totally removed. Histological diagnosis of the tumor was immature teratoma. Intracranial teratomas have a predilection for supratentorial and midline sites. They are the most common in the neonatal period. We presented a very rare case of teratoma in the cerebellar hemisphere of an infant.

Cerebellar Neoplasms↗
PubMed2001

[A case of Castleman lymphoma in the right pulmonary hilum and mediastinum].

A 36-year-old man who complained of low grade fever and cough was detected an abnormal shadow in the right pulmonary hilum and mediastinum on a chest X-ray film. On admission, laboratory data showed high CRP and hyper gamma globlinemia. In thoracotomy, original tumor and mediastinal lymph node were resected. Histopathologically, main tumor and two of all the resected lymph node were diagnosed as Castleman lymphoma (plasma cell type). We consider that not only the main tumor and also the peripheral lymph node should be resected in this disease, because the lesions were often showed multicentric if this tumor were plasma cell type.

Adult↗
PubMed2001

[Evaluation of time dependency of the acetazolamide effect on cerebral hemodynamics as measured by 99mTc-ECD single-photon emission computed tomography].

PURPOSE: Kuwabara et al. have examined the cerebral artery dilation with acetazolamide (ACZ) challenge test using PET. And, they reported that ACZ reaction came out time dependently. We have developed a unique SPECT's method using Technetium-99m ethyl cysteinate dimer (99mTc-ECD) to verify the results obtained by Kuwabara et al. METHOD: 1000 MBq of 99mTc-ECD was exactly divided into three syringes. Each of which was intravenous infused (i.v.) at rest, 7.5, and 20 minutes after ACZ administration. Data collection was started using dynamic SPECT immediately after 99mTc-ECD i.v. at rest. Using necessary data only, SPECT images representing each of the three 99mTc-ECD i.v. was reconstructed. SPECT counts were obtained by the ROI method from each images to calculate relative CBF from rest to 7.5 and 20 minutes after ACZ administration. RESULT: The 18 hemispheres of nine patients in the negative control group in whom ACZ was not loaded. CBF was stable during the three evaluation. The measurement error our method was estimated as small. The 18 hemispheres of nine patients in the positive control group who has normal vasodilatory reserve, CBF was increased by 26.2 +/- 8.1% at 7.5 minutes and 29.3 +/- 13.1% at 20 minutes after ACZ administration. Seven patients with and chronic stage unilateral internal carotid artery severe stenosis and/or occlusion were evaluated as the test group. Case of unaffected side, CBF was increased by 17.6 +/- 6.9% at 7.5 minutes and 24.8 +/- 11.3% 20 minutes after ACZ administration. And, increase rate of CBF in the affected side was 2.8 +/- 1.6% at 7.5 minutes and 17.3 +/- 5.0% at 20 minutes after ACZ administration. In the affected side, timing of the maximum CBF increase caused by ACZ was remarkably delayed. CONCLUSION: Our method based on 99mTc-ECD SPECT also revealed delayed cerebral artery dilation in the affected side. It was suggested that ACZ reaction came out time dependently, as reported by Kuwabara et al.

Acetazolamide↗
PubMed2001

[A resected case of multiple lung cancers].

A 78-year-old man was admitted to our hospital because of abnormal shadows on chest film. A 20 x 25 mm tumor shadow was found in the right lower lung field (S10) and a 5 x 10 mm tumor shadow in the right upper lung field (S2). Bronchoscopic curettage revealed squamous cell carcinoma from the specimen on the S10 and did not revealed malignant cells from the specimen on the S2. He was performed operation, squamous cell carcinoma in the S10 was removed by right lower lobectomy and nodule in the S2 was also removed by partial resection. Histological examination confirmed well-differentiated squamous cell carcinoma from the S10 and well-differentiated adenocarcinoma from the S2. He is healthy three year after operation.

Adenocarcinoma↗
PubMed2001

Hypermethylation of p16(INK4a) and p15(INK4b) genes in non-small cell lung cancer.

Hypermethylation of CpG island is a common mechanism by which tumor suppressor genes are inactivated. The tumor suppressor genes p16(INK4a) and p15(INK4b) are important components of the cell cycles. We have studied the feasibility of detecting tumor-associated aberrant p16(INK4a) and p15(INK4b) methylation in non-small cell lung cancer (NSCLC) using methylation-specific PCR. We found a high frequency of hypermethylation of the p16(INK4a) gene in 17 of 45 cases of NSCLC. In this study, there was no difference between the clinicopathological features or overall survival of patients with and without p16(INK4a) methylation. On the other hand, p15(INK4b) promoter hypermethylation is rare (5/45) in lung cancer and occurs in association with p16(INK4a) methylation. The overall survival of patients with p15(INK4b) methylation was markedly shortened in this series. We also analyzed cells in bronchial washings, and p16(INK4a) methylation was detected in 4 of 17 cases of NSCLC. Moreover, 1 of 10 plasma samples from patients with NSCLC was positive for p16(INK4a) methylation. Our results suggest a possible prognostic role of p15(INK4b) methylation in NSCLC, and that the detection of aberrant p16(INK4a) methylation in both bronchial washings and plasma may be useful for cancer diagnosis.

Adult↗
PubMed2001

[Endoventricular circular patch plasty (dor operation) for postinfarction left ventricular aneurysm and ischemic cardiomyopathy].

The determination of purse-string suture line is one of the most important point in endoventricular circular patch plasty (Dor operation) for postinfarction left ventricular aneurysm (LVAN), especially for ischemic cardiomyopathy (ICM). We suggest following three points to decide appropriate suture line. First, the purse-string suture on the basal side should be placed on the 1-2 cm level under diagonal branch. Secondly, lateral wall should not be over excluded to maintain left ventricular function. And the third, akinetic or dyskinetic lesion of apex and septal wall should be excluded as much as possible. Nine cases of five LVAN and four ICM were underwent Dor operation in our institute from Dec. 1999 to Jan. 2000. All patients were weaned from cardiopulmonary bypass easily except one patient, who was operated under IABP support, because of his preoperative severe heart failure. All patients recovered well without any serious complications and postoperative left ventricular graphies were satisfactory. Left ventricular ejection fraction and stroke volume index were increased from 34 +/- 17 to 55 +/- 16% and from 38 +/- 7 to 47 +/- 6 ml/m2, end-diastric and systric volume index decreased from 141 +/- 37 to 88 +/- 19 ml/m2 and from 96 +/- 41 to 41 +/- 23 ml/m2 respectively. The Dor procedure adopted our idea led to satisfactory result in hemodynamic and also in morphologic study.

Aged↗
PubMed2001

[Detection of visceral ischemia with doplex scanning method of mesenteric arteries: in patients with acute type B aortic dissection].

Between March, 1997 and January, 1999, 11 patients with acute type B aortic dissection underwent doplex scanning evaluation of mesenteric arteries for the early detection of visceral ischemia. Peak systolic velocity (PSV) of the celiac artery (CeA) and superior mesenteric artery (SMA) was measured on their admission. Mean PSV of CeA in the non-ischemic group (8 patients) and in the ischemic group (3 patients) was 1.66 +/- 0.34 m/sec and 3.60 +/- 0.49 m/sec (p = 0.0481), respectively. Mean PSV of the SMA in the non-ischemic group and in the ischemic group was 1.93 +/- 0.52 m/sec and 3.33 +/- 0.37 m/sec (p = 0.00768), respectively. All patients with PSV of the mesenteric arteries above 3.00 m/sec presented visceral ischemia that required emergency operation. If PSV of the mesenteric arteries exceeds 3.00 m/sec, urgent surgical repair should be considered.

Aged↗