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Biomedical subjects

Y Aoki

Publications and source records attributed to Y Aoki.

At least 109 records · Page 6Linked to original sources
PubMed2001

von Recklinghausen disease complicated by pulmonary hypertension.

Two patients with von Recklinghausen disease (neurofibromatosis type 1) were admitted to the hospital because of progressive heart failure. Both patients had prominent pulmonary hypertension revealed on cardiac catheterization. A lung perfusion scan did not show any gross defect. There were no underlying causes of pulmonary hypertension in either patient, such as chronic lung disease, congenital or acquired heart disease, deep vein thrombosis, or systemic hypercoagulable states. There may be an unrecognized association between von Recklinghausen disease and pulmonary hypertension.

Adult↗
PubMed2001

Comparison of the likelihood ratio and identity-by-state scoring methods for analyzing sib-pair test cases: a study using computer simulation.

To assess the power and significance of the likelihood ratio (LR) and the identity-by-state scoring (IBS) methods for a pair of siblings, we performed computer simulations by use of 10 DNA markers (HLA-DQalpha, D1S80, and 8 short tandem repeat loci) that were frequently analyzed in paternity tests in Japan. The combined power of discrimination of these 10 markers in the Japanese population is 0.999 999 999 98. Pedigrees each consisting of 10,000 pair of full-siblings, half-siblings and unrelated individuals were generated and typed on all markers as random samples. Both the summation of log10 LR and IBS of each group had approximate standard normal distribution with significant differences between the means. Statistical studies showed that the LR method has 91% power to detect unrelated individuals and 38% power to detect half-siblings as not full-siblings with a 5% false-positive rate, whereas the IBS method does 87% and 42% powers, respectively. In 62% of full-siblings, in contrast with only 0.2% of unrelated individuals, the values of LR exceeded 100 which was equivalent to 0.99 of probability of full-sibship at 50% prior probability. The advantage of the LR method over IBS method was convincing especially for the detection of unrelated individuals as not half-siblings, however, the latter would be also informative for sib-pair tests if sufficient number of polymorphic markers are available.

Algorithms↗
PubMed2001

Dioctophymatid nematode larva found from human skin with creeping eruption.

A female dioctophymatid nematode larva, presumably belonging to the genus Dioctophyme, was found in a dermal granuloma accompanied by creeping eruption in the left inner thigh of a 26-yr-old Chinese woman who had stayed in Japan for 4 yr. Morphology of the sectioned worm is described in detail. This is the fourth case of dermal infection with dioctophymatid larva in humans.

Adult↗
PubMed2001

Legionnaires' disease associated with habitual drinking of hot spring water.

A 57-year-old man presented with pneumonia, respiratory distress, and myelodysplastic syndrome. A diagnosis of Legionnaires' disease due to Legionella pneumophila (L. pneumophila) was established. The patient had long been drinking tap water via a conduit from a hot spring resource, from which L. pneumophila was also isolated. Both the patient's strain and the water strain of L. pneumophila were identified as serogroup 1, and the genetic relatedness between the two strains as seen by pulsed-field gel electrophoresis was 87%. The patient was successfully treated with erythromycin, fluoroquinolone, and rifampicin. This case raises an important issue on public health represented by legionellosis in Japan.

Drinking Behavior↗
PubMed2001

Insulin and somatostatin releasing islet cell tumor caused hypoglycemia.

We report a hypoglycemic case with normal insulin levels, which was caused by an islet cell tumor that was releasing insulin and somatostatin. A fasting test suggested the over secretion of insulin. Moreover, this hypoglycemia was enhanced by the inhibitory effect of somatostatin on the secretion of insulin counter-regulatory hormones, such as glucagon, in addition to the autonomous secretion of insulin from the tumor. In cases of hypoglycemia with apparently normal insulin levels, the measurement of somatostatin and various provocative tests are recommended. Arterial stimulation venous sampling (ASVS) was useful to detect the location of this functioning islet cell tumor.

Adenoma, Islet Cell↗
PubMed2001

Duodenal somatostatinoma and erythrocytosis in a patient with von Hippel-Lindau disease type 2A.

A female with von Hippel-Lindau (VHL) disease type 2A first presented with erythrocytosis at the age of 9 years. This patient revealed multiple paragangliomas at age 22. After the removal of tumors, a retinal hemangioblastoma developed. Our diagnosis of VHL disease type 2A was confirmed. Moreover, systemic examination showed a duodenal somatostatinoma. Frequent and long-term monitoring is important for patients with pheochromocytomas or paragangliomas, and a screening for VHL disease and other hereditary cancer syndromes is recommended. Recognition of neuroendocrine tumors as a manifestation of VHL disease permits earlier diagnosis and improves prognosis.

Adult↗
PubMed2001

Vascular endothelial growth factor/vascular permeability factor in the pathogenesis of primary effusion lymphomas.

Primary effusion lymphomas (PEL), rare lymphomas associated with Kaposi's sarcoma-associated herpesvirus (KSHV or HHV-8) infection, present as malignant lymphomatous effusions in body cavities. We have recently found that PEL effusions contain high levels of vascular endothelial growth factor/vascular permeability factor (VEGF/VPF). VEGF/VPF, an important regulator of tumor-angiogenesis in vivo, exerts its effects acting through the receptors KDR/Flk-1 and Flt-1 on the endothelial cell membrane. In vitro, the PEL cell lines BC-1, BCP-1 and BCBL-1 produce high levels of VEGF. RT-PCR analysis of RNA from the PEL cell lines amplified the three VEGF/VPF secreted isoforms, VEGF/VPF(121), VEGF/VPF(145) and VEGF/VPF(165). Two of the PEL cell lines express the VEGF/VPF receptor Flt-1, but VEGF did not stimulate proliferation in these cells. SCID/beige mice inoculated intraperitoneally with BCBL-1 cells developed effusion lymphoma of human cell origin with prominent bloody ascites. In contrast, none of the mice treated with a neutralizing anti-human VEGF/VPF antibody developed ascites and effusion lymphoma. Although the precise mechanisms by which VEGF/VPF can promote vascular permeability are not fully understood, VEGF/VPF stimulation of vascular leakage may be critical to the pathogenesis of PEL.

Animals↗
PubMed2001

Effective plasma concentration of a novel Na+/Ca2+ channel blocker NS-7 for its cerebroprotective actions in rats with a transient middle cerebral artery occlusion.

The effect of a novel Na+/Ca2+ channel blocker NS-7 [4-(4-fluorophenyl)-2-methyl-6-(5-piperidinopentyloxy) pyrimidine hydrochloride] on the cerebral infarction, edema, and mortality was examined in rats with a transient middle cerebral artery occlusion (MCAO), and the effective plasma concentration of this compound for producing the cerebroprotective action was subsequently determined. MCA was occluded by inserting a thread through internal carotid artery for 2 h, and then recirculated for 6 h. NS-7 (0.125-1 mg/kg), when injected i.v. immediately after recirculation, significantly reduced the infarct volume as well as the cerebral edema. Delayed treatment with NS-7 at 1 h after recirculation produced an equivalent inhibition of the infarction, and was still effective, although to a lesser extent, when injected at 2 h but not 3 h after recirculation. Glycerol (4 g/kg) suppressed the cerebral edema but did not reduce the size of cerebral infarction in the cerebral cortex or striatum. Therefore, it is likely that the suppression of brain edema does not always lead to the reduction of the infarct size. NS-7 treated in combination with glycerol further decreased the water content in the occluded brain. Moreover, NS-7 significantly lowered the mortality observed up to 10 days after a transient MCAO. From these data, it is suggested that the presence of NS-7 in plasma during 1 to 3 h after recirculation is important for producing the neuroprotective action. To determine the pharmacologically effective plasma concentration of NS-7, the effect of continuous infusion of this compound on the cerebral infarction was examined. Infusion of NS-7 at 0.3 mg/kg over 2 h, starting immediately after recirculation, significantly reduced the infarct size. Its plasma concentration during 1 to 3 h was 14.5 to 28.5 ng/ml (36.9-72.3 nM). From these finding it is suggested that NS-7 has a potent anti-infarct action in addition to antiedema action in the rat transient MCAO model. Moreover, its effective plasma concentration was assumed to be 36.9 to 72.3 nM.

Animals↗
PubMed2001

Ovarian function after radical hysterectomy with ovarian preservation for cervical cancer.

OBJECTIVE: To investigate the function of preserved ovaries following radical hysterectomy in premenopausal women with cervical carcinoma and to attempt to identify clinical factors influencing ovarian function. STUDY DESIGN: Between 1991 and 1998, 33 premenopausal patients with International Federation of Gynecology and Obstetrics stage IB and II cervical cancer underwent radical hysterectomy with ovarian preservation, including lateral ovarian transposition in 20 patients. In 12 cases of squamous cell carcinoma with deep stromal invasion or a suspicious, positive node, neoadjuvant chemotherapy was performed. Postoperative whole pelvic radiotherapy was administered to 11 patients. Ovarian function was evaluated by serum FSH level during the follow-up period, 12 months to 9 years. RESULTS: Fifteen of 33 patients became climacteric after treatment. Ten of 12 patients over 40 years old became climacteric, as did 5 of 21 under 39 (P = .0013). Using multiple regression analysis, a significant correlation between ovarian dysfunction and age (under 40) was observed (P = .0286). No ovarian recurrence or symptomatic ovarian cyst was observed in preserved ovaries during the study period. CONCLUSION: Ovarian preservation is safe in patients under 40 years old undergoing radical hysterectomy even if they received additional treatment, such as neoadjuvant chemotherapy or postoperative radiotherapy with ovarian transposition.

Adenocarcinoma↗
PubMed2001

[Nitric oxide and endothelins in pulmonary hypertension].

For recent decades, the medical treatment of primary pulmonary hypertension(PH) have shown an improved outcome as a bridge to lung transplantation. Both nitric oxide (NO) and endothelin(ET) have reported as a major vasoactive mediators in initiating PH. NO is a potent vasodilator released from endothelial cells to adjacent smooth muscle cells in vascular wall. Inhalation of NO has exerted dramatic effects with minimum complication for PH patients. ET-1, after binding to ETA receptor, promotes a strong vasoconstriction, cell growth and platelet aggregation. ETB receptor promotes the clearance of circulating ET-1 in the lung, and stimulates the release of NO and PGI2. Therapeutic trials of ETA receptor antagonist and NO donors for PH may be promising because of their direct action against vasoconstriction.

Endothelin Receptor Antagonists↗
PubMed2001

[Gastrointestinal bleeding from capillary hemangioma of the ileum detected by 99mTc-HSAD scintigraphy].

It has been well-known that technetium-99m-human serum albumin-diethylenetriaminepenta-acetic acid (99mTc-HSAD) scintigraphy is useful for diagnosis of the localization of the gastrointestinal arterial or venous bleeding. In this report, we describe a case of venous bleeding from capillary hemangioma of the ileum end detected by 99mTc-HSAD scintigraphy. This patient was a 9-year-old girl with severe anemia. Gastrointestinal bleeding was suspected from her clinical course and laboratory tests. Immediately after melena occurred, 99mTc-HSAD scintigraphy showed the extravasation of RI suggesting gastrointestinal bleeding in the ileum end. Abdominal angiography immediately after 99mTc-HSAD scintigraphy, however, could not show the extravasation of contrast agent. Because the condition of the patient became worse, laparotomy was performed on the basis of 99mTc-HSAD scintigraphy findings. At surgery, venous bleeding from capillary hemangioma in the ileum end was observed. It was suggested that 99mTc-HSAD scintigraphy was very useful for identifying the gastrointestinal venous bleeding.

Child↗
PubMed2001

[Clinical evaluation of "Takotsubo" cardiomyopathy with 123I-MIBG myocardial scintigraphy: a case report].

We report a case of "Takotsubo" cardiomyopathy that was considered to be caused by hypercatecholaminemia due to mental stress. Myocardial scintigraphy using 123I-MIBG revealed severe damage to the myocardial sympathetic nerve terminals at the site of reduced left ventricular wall motion on left ventriculography. In this case, cardiac nuclear imaging with 123I-MIBG appeared to be useful for understanding the pathophysiology when combined with ECG and left ventriculography.

3-Iodobenzylguanidine↗
PubMed2001

MR imaging underestimates stromal invasion in patients with adenocarcinoma of the uterine cervix.

PURPOSE OF INVESTIGATION: To evaluate magnetic resonance (MR) imaging in assessing the depth of stromal invasion in patients with adenocarcinoma of the uterine cervix. METHODS: Twenty-three women with adenocarcinoma of the cervix underwent T2-weighted and dynamic MR imaging before surgical evaluation. The images were evaluated for the depth of stromal invasion and compared with histological results. RESULTS: Twelve of 23 patients (52%) were correctly diagnosed in agreement with the histological findings. However, the depth of stromal invasion was underestimated in ten patients (44%). In four of nine patients who exhibited scattered type lesions, no lesions were detected by MR imaging, although deep stromal invasion (more than 1/3) was recognized histologically. In contrast, all 11 patients showed cancer lesions in solid type adenocarcinomas with deep stromal invasion. CONCLUSION: MR imaging detected less stromal invasive lesions in adenocarcinoma of the cervix than surgical specimens, and some scattered type adenocarcinomas could not be visualized.

Adenocarcinoma↗
PubMed2001

[A case of desmoplastic malignant pleural mesothelioma].

A 71-year-old woman with no history of asbestos exposure was referred to our hospital for evaluation of mediastinal soft tissue density. Six months prior to the admission, she had developed back pain and had been diagnosed as having intercostal neuralgia. Since the symptoms progressed, she was referred to another hospital. While chest radiography revealed no abnormality, chest computed tomography showed the prominence of mediastinal soft tissue, extending to the left hilum and partially destroying the nearby vertebrae. However, no pleural effusion was noted. After admission, a thoracoscopic examination was performed, and a whitish mass was found on the pleural surface partially adhering to the chest wall. Histological examination of the biopsied material showed dense areas of collagenous tissue with small foci of slightly atypical spindle cells. These findings led to the diagnosis of desmoplastic malignant pleural mesothelioma. The patient was treated with combined chemo-radiotherapy, but the response to this treatment was unclear. To date, reports for this subgroup of malignant mesothelioma are still rare.

Aged↗
PubMed2001

Effect of gravity change on the production of thrombopoietic growth factors.

It is reported that the stay in the space develops anemia, thrombocytopenia, and altered function and structure of red blood cell. The mechanism of these abnormalities was not clarified yet. The cloning of the thrombopoietin (TPO), followed by the analysis of TPO and c-mpl (its cellular receptor) knockout mice confirmed its role as the primary regulator of thrombopoiesis. TPO has been shown to stimulate both megakaryocyte colony growth from marrow progenitor cells and the maturation of immature megakaryocyte to form functional platelet. This process includes the massive cytoskeletal rearrangement, such as proplatelet formation and fragmentation of proplatelet. In this study we have focused on the production of thrombopoietic growth factors in mice those were exposed to gravity change by parabolic flight (PF).

Animals↗
PubMed2000

Inhibitory effect of a novel quinolinone derivative, TA-270, on asthmatic inflammatory responses in sensitized guinea pigs.

TA-270 (4-hydroxy-1-methyl-3-octyloxy-7-sinapinoylamino-2(1H)- quinolinone), a novel quinolinone derivative, was designed as an antioxidant to scavenge reactive oxygen species. Here, we investigated the effects of TA-270, in comparison with several antiasthmatic drugs, on asthmatic responses as induced by ovalbumin in sensitized guinea pigs. When orally administered 1 h before and 3 h after the antigen challenge, TA-270 at 10 mg/kg and higher doses significantly inhibited both immediate and late responses in airway resistance induced by the antigen. The inhibitory effects were comparable to or superior, at least under the present experimental conditions, to those of several clinically used antiasthmatic drugs. Furthermore, TA-270, in a dose-dependent manner, reduced accumulation of pulmonary inflammatory cells, especially eosinophils, and significantly reversed the airway hyperresponsiveness to acetylcholine 24 h after the antigen challenge. These results suggest that TA-270 may be of therapeutic use for bronchial asthma.

Acetylcholine↗
PubMed2000

High levels of human herpesvirus 8 viral load, human interleukin-6, interleukin-10, and C reactive protein correlate with exacerbation of multicentric castleman disease in HIV-infected patients.

Multicentric Castleman disease (MCD) is a distinct type of lymphoproliferative disorder associated with inflammatory symptoms and interleukin-6 (IL-6) dysregulation. In the context of human immunodeficiency virus (HIV) infection, MCD is associated with human herpesvirus 8 (HHV8) infection. In a prospective study of 23 HIV-infected patients with MCD, clinical symptoms of MCD were present at 45 visits, whereas patients were in chemotherapy-induced clinical remission at 50 visits. Symptoms were associated with a high level of serum C reactive protein, high HHV8 viral load in peripheral blood mononuclear cells, and high plasma human IL-6 and IL-10 levels. Strong correlations between plasma IL-6 and plasma IL-10 with the HHV8 viral load suggest that both cytokines may be involved in the pathogenesis of this virus-associated lymphoproliferative disorder.

Adult↗