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Biomedical subjects

H Ueno

Publications and source records attributed to H Ueno.

At least 217 records · Page 12Linked to original sources
PubMed1998

Blood pressure control during eye surgery under local anesthesia using pulse oximetry.

We measured the arterial blood pressure and percutaneous O2 saturation (SpO2) in 39 elderly patients (age range, 70-89 years) who underwent cataract surgery under local anesthesia. Nineteen patients showed a 20% or greater increase in the systolic arterial pressure (SAP) measured every minute in the operating room compared to the basal value measured in the ward. We treated elevation of the SAP by intravenous bolus injection of 0.25 mg nitroglycerin (NTG), followed by continuous infusion at 0.1-0.3 microg/kg/min. NTG caused a statistically significant but clinically irrelevant decrease in SpO2 in the patients breathing room air. Two of these patients showed extremely decreased SpO2. Our results suggest that NTG does not typically cause a severe decrease in oxygenation. It might be advisable, however, for patients with severe lung dysfunction or ischemic heart disease to receive prophylactic O2 administration.

Aged↗
PubMed1998

Diabetes mellitus and cardiomyopathy--association with mutation in the mitochondrial tRNA(Leu)(UUR) gene.

In this report, cardiac abnormalities in 2 diabetic patients with a mutation in the mitochondrial tRNA(Leu)(UUR)gene are described. The 2 patients exhibited left ventricular dilation and diffuse decreased wall motion. Cardiac catheterization studies revealed normal coronary angiography. In both patients, light microscopic examination of hematoxylin and eosin-stained sections revealed myocyte hypertrophy and perinuclear vacuolization and electron microscopy revealed an increase in the number and size of mitochondria and abnormal configuration of cristae. These findings suggest that mutations in mitochondrial DNA, such as an A-->G mutation at position 3243, should be considered as a cause not only of diabetes mellitus but also of cardiac involvement in patients with diabetes mellitus.

Cardiomyopathies↗
PubMed1998

Relationship between electrocardiographic voltage and geometric patterns of left ventricular hypertrophy in patients with essential hypertension.

To assess whether we could predict left ventricular (LV) geometric patterns on echocardiography from voltages in standard electrocardiograms (ECG) in patients with essential hypertension, standard 12-lead ECG and echocardiograms were recorded in 106 consecutive, untreated patients (50+/-11 yr old) with essential hypertension. Subjects were assigned to the following four groups based on relative wall thickness (RWT) and LV mass index (LVMI) as determined by echocardiography: a normal geometry group (n = 44), a concentric remodeling group (increased RWT and normal LVMI, n = 10), an eccentric hypertrophy group (increased LVMI and normal RWT, n = 23), and a concentric hypertrophy group (increased RWT and LVMI, n = 29). The following ECG variables were determined: Sokolow-Lyon voltage (SV1 = RV5: SL), Cornell voltage (RaVL + SV3: CN), sum of 12-lead QRS voltage (12-lead sum), and RV6/RV5 ratio (RV6/V5). LVMI correlated with SL, CN, and 12-lead sum, but not with RV6/V5 in the study group as a whole. The concentric hypertrophy group showed increased voltages for all ECG variables except RV6/V5. The concentric remodeling group showed increased voltages for SL and 12-lead sum, but a decreased RV6/V5 ratio. In contrast, the eccentric hypertrophy group had increased voltage only for the 12-lead sum. The combination of SL, RV6/V5, and CN showed modest sensitivity and specificity in the diagnosis of concentric remodeling, concentric hypertrophy, and normal geometry, but not in the diagnosis of eccentric hypertrophy. Conventional ECG criteria can predict LVMI, but not LV geometry in the patients with essential hypertension. The combination of SL, CN, and RV6/V5 is useful in differentiating the four LV geometric patterns seen in essential hypertension.

Adult↗
PubMed1998

Partial adenine phosphoribosyltransferase deficiency detected by ureterolithiasis.

A 30-year-old woman was admitted to our hospital because of recurrent ureterolithiasis. She was suspected of having adenine phosphoribosyltransferase (APRT) deficiency based on the presence of 2,8-dihydroxyadenine (DHA) crystals in her urinary sediment, infrared spectrophotometric analysis of the excreted stone, and then the definitive diagnosis by gene analysis. A pedigree study indicated only a slight possibility of this disease in the family. From these results, we consider that urinary sediment and stone analysis should be used for screening while gene analysis should be employed for definitive diagnosis of APRT deficiency, so that the complications of this condition can be prevented.

Adenine↗
PubMed1998

[Adult-onset type II citrullinemia in a patient undergoing continuous ambulatory peritoneal dialysis].

A 57-year-old Japanese man was admitted to Toyama Medical & Pharmaceutical University Hospital with delirium and flapping tremor on April 2, 1997. He had been undergoing continuous ambulatory peritoneal dialysis (CAPD) because of diabetic nephropathy since 1993. Blood chemistry showed slightly elevated plasma ammonia level with no evidence of liver injury, and his portal venography revealed no port-systemic shunt. He was diagnosed as having type II citrullinemia because of an elevated citrulline level on amino acid analysis and very low hepatic argininosuccinate synthetase activity obtained from biopsy specimen of liver. In this case, plasma concentrations of ammonia and citrulline were not so high as those in previously reported cases, although the hepatic argininosuccinate synthetase activity was actually less than 10% of the control value. Owing to CAPD, he was conservatively controlled in a relatively good condition. This indicates that CAPD seems to be a useful therapeutic approach for citrullinemia since liver transplantation is still difficult in Japan.

Ammonia↗
PubMed1998

Antitumor activity of alpha-galactosylceramide, KRN7000, in mice with EL-4 hepatic metastasis and its cytokine production.

Liver metastasis of primary tumor is a clinically major problem. KRN7000, an alpha-galactosylceramide, significantly augments natural killer (NK) activity of spleen cells and shows strong antitumor activity in mice with lung metastasis of melanoma B16 cells. To test whether KRN7000 has an antitumor activity in mice with hepatic metastasis of tumors, we examined the effect of KRN7000 on NK activity of hepatic mononuclear cells (MNC) and the antitumor activity in mice with liver metastasis of EL-4 cells. The in vivo administration of KRN7000 significantly augmented NK activity of hepatic MNC and inhibited tumor growth of EL-4 cells in the liver more markedly than chemotherapeutic agents, leading to a relatively high rate of cured mice. In addition, it appeared that the KRN7000 treatment is effective in mice with established EL-4 tumors. Moreover, we found that KRN7000 can produce significant amounts of interleukin 2 (IL-2), IL-4, IL-12, and interferon-gamma in a dose-dependent manner. These results suggest that KRN7000 will be useful for the treatment of cancer liver metastasis.

Animals↗
PubMed1998

[Electrophysiological specification of trabecular meshwork by dielectric dispersion method].

In an attempt to observe the dielectric behavior of the trabecular meshwork and to estimate its pumping of aqueous humor quantitatively, we measured tissue impedance of the anterior portion of 22 enucleated eyeballs from 11 rabbits non-invasively with a minute coaxial surface probe. Serial measurements of five points near the limbus revealed a significant decrease of the peak value (p < 0.05, paired t-test) on loss tangent function at a point 0.5 mm from the limbus towards the sclera. We considered that the decrease in the peak value at the point was due to broadening of the dielectric dispersion reflecting the microstructure of trabecular meshwork beneath the point. After removing the corneal epithelium, the limbal epithelium, and the conjunctiva, we also observed a decrease in the peak value at the same point, which reinforced our assumption that we can identify the trabecular meshwork electrophysiologically by means of dielectric dispersion.

Animals↗
PubMed1998

Characterization of the immunopathogenic responses to ovalbumin peptide 323-339 in experimental immune-mediated blepharoconjunctivitis in Lewis rats.

PURPOSE: We recently reported the essential role of cellular immunity on the induction of experimental immune-mediated blepharoconjunctivitis (EC, formerly EAC) by using ovalbumin (OVA) as a model antigen in Lewis rats. The purpose of this study was to investigate the possible induction of EC by immunization with an OVA peptide (OVA 323-339). METHODS: Lewis rats were immunized with various doses of OVA or OVA 323-339 in complete Freund's adjuvant. Three weeks later they were challenged with OVA or OVA 323-339 by eye drops; 24 h after challenge, eyes including lids, lymph nodes and blood were harvested after clinical evaluation. An OVA 323-339-specific cell line (S816) was established by periodical stimulation with this peptide. Pathogenicity of S816 was tested by adoptive transfer of S816 into syngeneic recipient rats after challenge with OVA or OVA 323-339. RESULTS: All rats immunized with OVA 323-339 developed EC after challenge with OVA or OVA 323-339. Rats immunized with OVA 323-339 at doses as low as 0.01 microg had severe clinical scores. OVA-primed rats also developed EC after challenge with OVA 323-339. OVA-primed lymph node cells responded to OVA but not to OVA 323-339. OVA 323-339-primed lymph node cells responded to OVA 323-339 but not to OVA and produced IFN-gamma by stimulation with either OVA or OVA 323-339 (three- to fourfold more than with OVA-primed lymph node cells). Recipient rats of S816 developed severe EC after challenge with either OVA or OVA 323-339. CONCLUSION: OVA 323-339 was identified as a potent pathogenic peptide in EC.

Adoptive Transfer↗
PubMed1998

[Clinical experience of autologous blood transfusion and fibrin glue in neurosurgery].

Clinical experience of autologous blood preservation on 83 patients and transfusion on 43 patients were reported. When drawing blood, 14 patients whose hemoglobin level was below 13 g/dl (body weight < 70 kg) or 14 g/dl (body weight > 70 kg) received subcutaneous recombinant human erythropoietin injection (s.c.) to facilitate erythropoiesis, according to the internal standard protocol. Hemoglobin levels of all the patients recovered to more than 10 g/dl by the time they were admitted to the hospital, which value would not interfere with general neurosurgical procedures. The injection of erythropoietin did not cause any side effects. Autologous blood transfusion was performed in 43 patients but, in 3 patients, additional homologous transfusion was required because of excessive bleeding. Except in cases with meningioma, postoperative hemoglobin values were identical with preoperative values, indicating that autologous blood transfusion was enough to replace intraoperative blood loss. Autologous fibrin glue was applied in 74 patients. In 70 cases including 55 with skull base surgery, the glue was applied to ensure dural closure. The incidence of cerebrospinal fluid leakage was 16.4% (5 patients) in skull base surgery. This incidence was identical to or less than that in previous reports. The glue was also effective in transposing and fixing offending vessels in 4 cases which received microvascular decompression. As a conclusion, procedures for autologous blood preservation and transfusion were safely performed in neurosurgical cases. Review of the literature was also presented to discuss the advantages and problems to be solved in the future.

Adolescent↗
PubMed1998

[Dielectric dispersions of alpha, beta H, beta L and gamma crystallin solutions].

The crystallins which constitute the major soluble proteins of the lens are known to change into insoluble proteins in aged or cataractous lenses. Such changes would affect protein-bound water and bulk water around the crystallin molecules. We measured the a.c. admittances of several kinds of crystallin, solutions in the frequency range from 10 kHz to 2 GHz to define the passive electrical properties of bound water. With the experimental data, we calculated the relative permittivity, conductivity, and loss factor. The admittance of crystallin solutions had essentially three dielectric dispersions and we could divide them into three dependent dispersions by a curve-fitting analysis based on a three-term Cole-Cole equation. The lowest frequency dispersion around a few MHz was due to protein particles, the middle frequency of the 10-100 MHz range to bound water, and the highest frequency of over 1 GHz to bulk water. The dielectric behavior of crystallin molecules and bound water depended on the protein concentration. With the increase in molecular weight of crystallins, the dielectric increments of both dispersions increased and the characteristic frequencies of the dispersions decreased significantly.

Crystallins↗
PubMed1998

[Theoretical impedance analysis of the intact rat lens with an ellipsoidal shells model].

We measured a.c. admittances for isolated rat lenses over a wide frequency range of 100 Hz to 500 MHz. In order to evade electrode polarization at low frequencies, we examined extracted lenses by direct semi-squeezing with Pt black-coated platinum electrodes. This gave rise to a 10(6) increment in permittivity at low frequencies, and two distinct dielectric dispersions were exhibited; dispersion 1 with a characteristic frequency (fc) of 2 kHz, and dispersion 2 with an fc of 2 MHz. In terms of loss tangent function, the two dispersions clearly dominated as two peaks. By curve fitting analysis with an allocated ellipsoidal-shells model based on ultrastructural features of the lens with a lens equivalent circuit, dispersion 1 was assigned to the equatorial cortex where regularly arranged lens fibers ran parallel to the applied electric field, and dispersion 2 to the nucleus of complicated fibers, combined with the polar cortex where lens fibers ran perpendicular to the electric field. Our results suggested that both lens dispersions were beta-dispersions attributable to bio-membranes.

Animals↗
PubMed1998

[Angiogenic gene therapy for ischemic heart disease].

Once myocardium is under hypoxia due to narrowing of coronary arteries, the myocardium produces angiogenic peptides such as fibroblast growth factors to develop collaterals to restore the blood supply to its ischemic region. Thus, if angiogenic growth factors are supplied exogenously, the development of collaterals should be facilitated, and may save myocardium from hypoxia, thereby enhancing heart function. In addition to the experiments using recombinant protein of angiogenic factors, recent reports showed that gene transfer of such angiogenic factors indeed restored blood supply into ischemic myocardium and enhanced its function, suggesting such approach being an effective new strategy for the treatment of ischemic heart disease. This brief review summarizes recent progress of angiogenic therapy.

Collateral Circulation↗
PubMed1997

CD1d-restricted and TCR-mediated activation of valpha14 NKT cells by glycosylceramides.

Natural killer T (NKT) lymphocytes express an invariant T cell antigen receptor (TCR) encoded by the Valpha14 and Jalpha281 gene segments. A glycosylceramide-containing alpha-anomeric sugar with a longer fatty acyl chain (C26) and sphingosine base (C18) was identified as a ligand for this TCR. Glycosylceramide-mediated proliferative responses of Valpha14 NKT cells were abrogated by treatment with chloroquine-concanamycin A or by monoclonal antibodies against CD1d/Vbeta8, CD40/CD40L, or B7/CTLA-4/CD28, but not by interference with the function of a transporter-associated protein. Thus, this lymphocyte shares distinct recognition systems with either T or NK cells.

Animals↗
PubMed1997

Prostaglandin E2 and IL-4 provide naive CD4+ T cells with distinct inhibitory signals for the priming of IFN-gamma production.

We investigated the effects of prostaglandin E2 and IL-4 on the acquisition of cytokine-producing ability by naive CD4(+) T cells in human umbilical cord blood. The presence of PGE2 or IL-4 at primary stimulation inhibited the production of IFN-gamma at secondary stimulation, and the combination of these stimuli resulted in cooperative effects. During primary stimulation with anti-CD3, the intracellular cAMP level was elevated in PGE2-treated cells but not in IL-4-treated or control cells. The signal provided by PGE2, but not by IL-4, was inhibited with RpcAMP, indicating that it was mediated by cAMP. After differentiation into Th2-like cells, cAMP levels in PGE2- and IL-4-treated cells were not different. Our results suggest that both PGE2 and IL-4 play important roles with distinct mechanisms in inhibiting the priming of IFN-gamma production of naive CD4(+) T cells.

CD4-Positive T-Lymphocytes↗