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Biomedical subjects

T Harada

Publications and source records attributed to T Harada.

At least 163 records · Page 9Linked to original sources
PubMed2000

Evaluation of the reliability of chromosomal imbalances detected by combined use of universal DNA amplification and comparative genomic hybridization.

Comparative genomic hybridization (CGH) analysis of microscopic tumor samples is allowed by universal DNA amplification using degenerate oligonucleotide primed-PCR (DOP-PCR). To evaluate the reliablity of DOP-PCR CGH, we performed DOP-PCR CGH and standard CGH in parallel using DNAs extracted from 10 malignant tumors of the hepatobiliary tract and pancreas. Similar results were obtained by both methods with a few exceptions, indicating that DOP-PCR CGH provides cytogenetic information equivalent to that obtained from standard CGH. We also investigated the sensitivity of DOP-PCR CGH using sequential dilutions of DNA from microdissected tumor cells. DOP-PCR using 100 to 800 pg of template DNA yielded successful CGH results. However, less than 50 pg of template DNA was not suitable because of the small amount of generated DNA. These findings suggest that DOP-PCR CGH is applicable for CGH analysis of tiny specimens which are too small for standard CGH. Accordingly, DOP-PCR CGH analysis may become a useful method in clinical laboratory examination.

Aged↗
PubMed2000

Electrocardiographic characteristics of left ventricular outflow tract tachycardia.

Catheter ablation of idiopathic left ventricular outflow tract tachycardia (LVOT-VT) is rare because a safe ablation technique at this site has not been described, and serious complications may occur. This study compared the QRS morphology of LVOT-VT with that of idiopathic right ventricular outflow tract tachycardia. A comparison was made between the electrocardiographic characteristics of LVOT-VT originating from the supravalvular region of a coronary cusp (Supra-Ao group) with those of LVOT-VT originating from the infravalvular endocardial region of a coronary cusp of the aortic valve within the LV (Infra-Ao group). After precise mapping of the right ventricle, left ventricle, pulmonary artery, coronary cusps, and proximal portion of the anterior interventricular vein, there were 17 patients in whom VT was thought to be located at the LVOT by both activation and pace mapping. They were divided between a Supra-Ao group (n = 8), and an Infra-Ao group (n = 9). Analysis of the 12-lead electrocardiogram (ECG) revealed an S wave in lead I in all 17 patients. A precordial R wave transition was also observed at V1 or V2 in 16 patients (94%). In 7 of 8 patients (88%) with Supra-Ao LVOT-VT, no S wave was observed in either V5 or V6. In contrast, an Rs pattern was observed in both V5 and V6, or in V6 only, in 100% of the patients with Infra-Ao LVOT-VT. A LVOT-VT should be suspected when the ECG shows an S wave in lead I and an R/S ratio greater than 1 in lead V1 or V2, versus a coronary cusp location if there is no S wave in either lead V5 or V6.

Adolescent↗
PubMed2000

E2-p7 region of the bovine viral diarrhea virus polyprotein: processing and functional studies.

The genes encoding pestivirus E2 and NS2-3 are separated by a sequence that encodes a small hydrophobic polypeptide with an apparent molecular mass of 6 to 7 kDa (p7). It has been shown that cleavage between E2 and p7 is incomplete, resulting in proteins E2-p7, E2, and p7. We found no precursor-product relationship between E2-p7 and E2, which indicates a stable nature of E2-p7. To study the function of the E2-p7 region of the polyprotein, mutations were introduced into an infectious cDNA of bovine viral diarrhea virus (BVDV). When cleavage between E2 and p7 was abolished, viral RNA replication occurred; however, no infectious virus could be recovered. A corresponding result was obtained with a construct encompassing a large in-frame deletion of p7. To prevent synthesis of E2-p7, a translational stop codon was introduced after the last codon of the E2 gene and an internal ribosome entry site element followed by a signal peptide coding sequence was inserted upstream of the p7 gene. Transfection of RNA transcribed from the bicistronic construct led to the release of infectious virus particles. Thus, synthesis of E2-p7 is not essential for the generation of infectious virions. Cell lines constitutively expressing BVDV p7 and/or E2 were generated for complementation studies. Transfection of BVDV RNAs with point mutations or a deletion in the E2-p7 region into the complementing cell lines led to the generation of infectious virions. According to our studies, p7 as well as E2 can be complemented in trans.

Animals↗
PubMed2000

Coasting may reduce the severity of the ovarian hyperstimulation syndrome in patients with polycystic ovary syndrome.

The aim of our study was to determine the efficacy of postponing administration of human chorionic gonadotropin while continuing daily gonadotropin-releasing hormone agonist therapy ('coasting') to prevent the occurrence of severe ovarian hyperstimulation syndrome (OHSS) for patients with polycystic ovary (PCO) syndrome. Five patients with PCO who had been hospitalized due to severe OHSS in previous in vitro fertilization and embryo transfer or intrauterine insemination cycles at the Tottori University Hospital were included in the study. The rates of mature oocytes and fertilization were comparable between the cycles. A singleton pregnancy was achieved in a patient during the coasting cycle, and none of the women developed severe OHSS in coasting cycles. The results suggest that coasting may be an alternative method for reducing the severity of OHSS in patients with PCO.

Adult↗
PubMed2000

Immunohistochemical localization of collagen types I, III, and IV, laminin, fibronectin, and keratin in the endolymphatic sac.

We have employed immunohistochemistry to obtain baseline information on the molecular constituents of the extracellular matrix (ECM) of the endolymphatic duct (ED) and endolymphatic sac (ES) of the chinchilla. The results demonstrated that collagen types I and III were distributed in the subepithelial layer in the ED and ES, type IV collagen and laminin in the basement membranes, and fibronectin in the subepithelial layer and partly in the conglomerated cells in the ES. Collagen type III was diffusely distributed in the whole subepithelial layer of the ES, whereas collagen type I was concentrated densely in the deep layer of the interstitium, although gradually, the cuboidal epithelium in the ES was transformed into a flatter type in the ED. The epithelial cells of the ED and ES were clearly positive for keratin. This study deals, in particular, with the normal distribution of ECM components of the ED and ES of the chinchilla.

Animals↗
PubMed2000

Tumor necrosis factor-alpha promotes proliferation of endometriotic stromal cells by inducing interleukin-8 gene and protein expression.

Endometriosis, a common disease among women of reproductive age, is characterized by the presence of endometrial-like tissue outside the uterus. We and others showed that several cytokine levels, including interleukin-8 (IL-8) and tumor necrosis factor-alpha (TNFalpha), are elevated in the peritoneal fluid of women with endometriosis compared with those in women without endometriosis. We also demonstrated that the addition of IL-8 to the culture medium stimulated the proliferation of cultured endometriotic stromal cells. TNFalpha is a multipotent cytokine that induces IL-8 production in various cell types. Therefore, we hypothesized that TNFalpha may also contribute to the pathogenesis of endometriosis by inducing the production of IL-8. To test this hypothesis, we analyzed the peritoneal fluid concentrations of IL-8 and TNFalpha using enzyme-linked immunosorbent assay (ELISA). We observed a significant correlation between the levels of TNFalpha and IL-8 in the peritoneal fluid of endometriosis patients. We also obtained the endometriotic stromal cells from chocolate cyst linings of the ovary. The expression of the receptors for TNFalpha (TNFR) was examined by RT-PCR. We observed the expression of both TNFR-I and TNFR-II genes in endometriotic stromal cells. The expression of IL-8 gene and protein was analyzed by Northern blot hybridization and enzyme-linked immunosorbent assay, respectively. TNFalpha induced the gene and protein expression of IL-8 in endometriotic stromal cells in a dose-dependent fashion. The addition of TNFalpha promoted the proliferation of the endometriotic stromal cells, and the stimulatory effects of TNFalpha were abolished by adding anti-IL-8 antibody. We demonstrated for the first time that TNFalpha stimulated proliferation of endometriotic stromal cells through induction of IL-8 gene and protein expression. We concluded that the TNFalpha may be one of the essential factors for the pathogenesis of endometriosis.

Adult↗
PubMed2000

Successful radiofrequency catheter ablation from the supravalvular region of the aortic valve in a patient with outflow tract ventricular tachycardia.

Outflow tract ventricular tachycardia (OT-VT) was successfully ablated from the right coronary cusp of the aortic valve. The 12-lead ECG was totally different from the typical right ventricular OT-VT because the R/S ratio in precordial lead V1 was equal to 1 and tall R waves in precordial leads V2-6 were seen. Radiofrequency energy application from the right coronary cusp of the aortic valve successfully ablated this VT without complications. Radiofrequency catheter ablation from the right coronary cusp of the aortic valve can be done safely and effectively.

Aged↗
PubMed2000

Left cervical aortic arch with aortic coarctation and saccular aneurysm.

Cervical aortic arch is a very rare malformation and is occasionally accompanied by other cardiovascular anomalies. A 48-year-old male patient had a left cervical aortic arch with aortic coarctation and saccular aneurysm distal to the coarcted segment. The major clinical manifestations were upper body hypertension with a 50-mmHg discrepancy between the upper and lower limbs and a loud continuous murmur in the upper chest and back. Magnetic resonance angiography successfully depicted the anomalous aorta, and the aortic coarctation and aneurysm were surgically resected and the thoracic aorta was reconstructed. The discrepancy in blood pressure diminished after the operation, but antihypertensive medication was continued to satisfactorily control the hypertension.

Aorta, Thoracic↗
PubMed2000

D0870, an antifungal agent, induces reverse use-dependent QT prolongation in dogs.

We previously reported that D0870 induced QT prolongation and sudden death due to torsades de pointes (TdP) in dogs and that catecholamines played an important part in the development of the sudden death. In the present study, we analyzed in detail the ambulatory electrocardiographic recordings obtained from the just-mentioned study to elucidate the mechanism of the onset of TdPs and conducted an in vitro study using isolated canine Purkinje fibers to assess the effect of D0870 on repolarization. The hearts with TdPs observed before the sudden death showed a higher sinus rate for 5 and 10 sec before the onset, a shorter coupling interval, and a higher ventricular tachycardia rate compared with those having the non-sustained TdPs. These findings suggest that D0870-induced fatal TdPs may be provoked by a triggered activity developed from delayed after depolarizations. In contrast, as the pause-dependent, non-sustained TdPs in bradycardia showed a typical "short-long-short" sequence, they may be developed from early afterdepolarization . Moreover, the results of the in vitro study supported our contention that D0870 induced QT prolongation in a reverse use-dependent manner in vivo and suggested that it may inhibit not only rapidly activating delayed rectifier potassium current (Ik(r)) but also L-type Ca current (I(ca-L)).

Action Potentials↗
PubMed2000

Mechanism for the development of ovarian cysts in patients with congenital lipoid adrenal hyperplasia.

OBJECTIVE: Although ovarian cysts commonly occur in patients with congenital lipoid adrenal hyperplasia (CLAH), the mechanism of development remains to be determined. To clarify the pathogenesis of the ovarian cysts, endocrinological examinations were performed in patients with CLAH. METHODS: The subjects were three Japanese CLAH patients. Basal body temperature, serum and urinary gonadotropin levels, serum and/or urinary ovarian hormones and mutations of the steroidogenic acute regulatory protein (StAR) gene were examined. RESULTS: The basal body temperature was not biphasic in any patient. Basal LH levels were high in all CLAH patients and markedly responded to LH-releasing hormone in two patients. Urinary gonadotropin analysis revealed repetitive LH surges in the menstrual cycles of the CLAH patients. No increase in the urinary pregnanediol suggested anovulation in all patients, and bilateral ovarian cysts were found in two of the subjects. Examination of the StAR gene revealed a frameshift mutation 840delA at codon 238, a nonsense mutation Q258X at codon 258, a homozygotic mutation at Q258X, and a compound heterozygotic mutation with 251insG and Q258X. CONCLUSIONS: We concluded that the development of ovarian cysts may be derived from continued anovulation in CLAH patients. Elevated LH levels may be explained by increased sensitivity of the anterior pituitary to circulating estrogen.

Adolescent↗
PubMed2000

Inhibitory effects of repeated intravenous injections of dexamethasone on pulmonary toxicity of a new mitomycin C analogue, KW-2149, in a novel rat model.

An animal model for testing pulmonary toxicity of KW-2149, a new mitomycin C analogue, was developed (by intravenously injecting 3.28 mg/kg of the drug into male SD rats 3 times at weekly intervals), and exhibits pleural effusion from 1 week after the last injection. In this animal model, repeated intravenous injections of dexamethasone (DM), following any of three different schedules examined, were more or less effective of reducing the amount of effusion. The optimal results were obtained with 4 administrations a week (i.e. twice before and twice after KW-2149 treatment). The results of the present experiment suggest possible clinical application of DM in protecting patients from pulmonary toxicity of KW-2149.

Animals↗
PubMed2000

[An aged case of bilateral ballistic movement which was thought to be exacerbated by respiratory insufficiency].

We report a 75-year-old man who had shown bilateral ballistic movements. He had suffered from pulmonary emphysema for about 35 years and was treated with oxygen therapy 3 years before. When he was 70 years old, involuntary movements appeared in bilateral limbs. His involuntary movements were ballistic, and become gradually worse. T2-weighted MRI after admission demonstrated high signal intensities in the bilateral pallidum, indicating multiple brain infarcts in the subcortical white matter. Ultrasonography showed 2 plaques in the left common carotid artery. Laboratory studies revealed blood coagulation abnormalities and hypoxia. Medication with clonazepam and tiapride together with oxygen therapy normalized blood gas levels and improved his involuntary movements. But after discharge, he stopped oxygen therapy and involuntary movement became worse again, associated with hypoxia demonstrated by his blood gas analysis. These findings suggest that not only cerebrovascular disease but hypoxia might play an important role in the appearance and exacerbation of involuntary movements.

Aged↗
PubMed2000

Expression of cell cycle regulator genes in KB, a human squamous cell carcinoma cell line, after irradiation.

DNA damage induced by irradiation causes overexpression of the p53 gene, and subsequently the upregulation of p53 downstream genes involved in cell cycle modification. Irradiated malignant cells which possess wild-type p53 have been known to undergo G1 arrest due to p21/Cip1/Waf1 upregulation. Other p53 downstream genes related to the modification of the cell cycle such as gadd45 may cause G2 arrest. Many of the genes which regulate the cell cycle progression have been identified, including the G1 phase specific ink4 family of cyclin-dependent kinase inhibitors (CDK-I), another group of CDK-Is, which affect the cyclin-CDK complexes ubiquitously, and S/G2 accelerator genes. The sequential changes in these cell cycle regulator genes after irradiation has not been clarified. We analyzed the appearance of the apoptotic fraction and cell cycle perturbation after irradiation using KB, a human squamous cell carcinoma line derived from oral floor, and examined the alteration of gene expression for cell cycle regulator genes. The KB cells proceeded to undergo apoptosis in a time and dose dependent manner after irradiation and showed G2 arrest accompanied by upregulation of p53, ubiquitous CDK-Is, and S and G2 accelerator genes.

Apoptosis↗
PubMed2000

Coexisting thymic and gastric lymphomas of mucosa-associated lymphoid tissues in a patient with Sjögren syndrome.

Lymphomas of mucosa-associated lymphoid tissues (MALTomas) arising from the thymus are extremely rare. In this case report, we describe a 36-year-old woman with an 11-year history of Sjögren syndrome who was found to have a thymic MALToma coexisting with a gastric MALToma. Both tumors shared similar histologic features, showing clusters of centrocytic-like B cells, lymphoepithelial lesions, and prominent plasmacytic differentiation. They also showed the following identical immunohistochemical features: CD20(+), IgA/lambda(+), CD5(-), and CD43(-). Molecular studies using polymerase chain reaction methods revealed monoclonal gene rearrangement of the immunoglobulin heavy chain in the gastric MALToma, but not in the thymic MALToma. The possible pathogenesis of this unusual case is discussed.

Adult↗
PubMed2000

[Efficacy of single-dose therapy with levofloxacin for acute cystitis: comparison to three-day therapy].

To investigate the safety, efficacy and recurrence-inhibiting effect of a single dose of levofloxacin (LVFX) for the treatment of acute uncomplicated cystitis in women, 56 females with acute uncomplicated cystitis between 17 and 73 years old were studied, based on the urinary tract infection (UTI) drug efficacy evaluation. The patients were divided into two groups; in Group A a single 200 mg dose of LVFX was administered, while in Group B, 100 mg of LVFX was administered twice a day for three days. The patients were re-examined three days later. The presence or absence of recurrence was surveyed by a questionnaire 3 months after the treatment. The efficacy rate on the third day after the administration in Group A and Group B was 96.9% (32 cases) and 95.8% (24 cases), respectively, and the recurrence rate within three months after administration 17.4% (4 in 23 cases) and 5.6% (1 in 18 cases), respectively. As for adverse drug reaction, abdominal pain was seen in one case, without a clear cause-effect relationship. Although the number of cases studied was small, no significant difference was seen between the single dose group and 3-day dose group in the safety, efficacy and recurrence-inhibiting effect of the new quinolone antibacterial treatment for acute uncomplicated cystitis in women, confirming the usefulness of the single dose treatment.

Acute Disease↗
PubMed2000

[A case of alcoholic multiple nervous system degeneration].

Chronic ethyl alcohol abuse is associated with different types of neurological involvement. We report a 51-year-old woman with alcoholic encephalopathy, neuropathy and autonomic dysfunction. After the alcohol abuse of about thirty years, gait disturbance, dysphagia and dysarthria progressively worsened. We thought that the disease was caused by poor nutrition due to chronic alcohol abuse and vitamin B1, B12 deficiency. Her neurological symptoms and signs improved after discontinuation of alcohol and nutritional treatment.

Alcohol-Induced Disorders, Nervous System↗
PubMed2000

[Efficacy of continuous intravenous drip infusion of disopyramide in hypertrophic obstructive cardiomyopathy during cardiogenic shock: a case report].

A 54-year-old woman was admitted to our hospital complaining of dyspnea due to hypertrophic obstructive cardiomyopathy. On admission, she was treated with 4 antiarrhythmic drugs and 2 beta-blockers. After 4 of these 6 drugs were withdrawn, the left ventricular outflow pressure gradient markedly increased and then she fell into cardiogenic shock. Therefore, disopyramide(600 mg/day) was administered by continuous intravenous drip infusion to reduce the left ventricular outflow pressure gradient. After intravenous administration of disopyramide, the left ventricular outflow pressure gradient markedly decreased from 100 to 16 mmHg and the cardiogenic shock could be improved. Continuous intravenous drip infusion of disopyramide is effective for the treatment of cardiogenic shock due to severe left ventricular outflow obstruction in patients with hypertrophic obstructive cardiomyopathy.

Anti-Arrhythmia Agents↗