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H Hashimoto

Publications and source records attributed to H Hashimoto.

At least 415 records · Page 23Linked to original sources
PubMed1997

Isoform-specific up-regulation by ouabain of Na+,K+-ATPase in cultured rat astrocytes.

There are two alpha-subunit isoforms (alpha1 and alpha2) and two beta-subunit isoforms (beta1 and beta2) of Na+,K+-ATPase in astrocytes, but the functional heterodimer composition is not known. Ouabain (0.5-1.0 mM) increased the levels of alpha1 and beta1 mRNAs, whereas it decreased those of alpha2 and beta2 mRNAs in cultured rat astrocytes. The increases in alpha1 and beta1 mRNAs were observed at 6-48 h after addition of the inhibitor. Immunochemical analyses showed that ouabain increased alpha1 and beta1, but not alpha2 and beta2, proteins, and that the isoforms in control and ouabain-treated cultures were of glial origin. Low extracellular K+ and monensin (20 microM) mimicked the effect of ouabain on alpha1 mRNA. The ouabain-induced increase in alpha1 mRNA was blocked by the protein synthesis inhibitor cycloheximide (10 microM), the intracellular Ca2+ chelator 1,2-bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid tetraacetoxymethyl ester (30 microM), and the calcineurin inhibitor FK506 (1 nM). These findings indicate that chronic inhibition of Na+,K+-ATPase up-regulates the alpha1 and beta1, but not alpha2 and beta2, isoforms in astrocytes, suggesting a functional coupling of alpha1beta1 complex. They also suggest that intracellular Na+, Ca2+, and calcineurin may be involved in ouabain-induced up-regulation of the enzyme in astrocytes.

Animals↗
PubMed1997

Molecular cloning and growth hormone-regulated gene expression of carp insulin-like growth factor-I.

Two distinct insulin-like growth factor-I (IGF-I) cDNAs were isolated from a juvenile carp liver cDNA library. Both of the cDNAs encoded a full length prepro IGF-I with 161 amino acids: a mature peptide (70 residues), its signal peptide (44 residues), and a carboxy-terminal E domain (47 residues). The similarity of the two cDNA in the open reading frame was 95.1%. The amino acid sequences of E domain predicted by the two cDNAs were different while those of the signal peptide and the mature peptide were the same. By Northern blot analysis, four different sizes (1, 1.5, 2, and 4.5 kb) of IGF-I mRNA were recognized in the liver of juvenile carp. The two smaller species (1 kb and 1.5 kb) were not detected in adult carp. The expression of these two species was preferably induced by exogenous growth hormone administration in the liver of juvenile carp.

Aging↗
PubMed1997

Detection of antibodies to a recombinant gag protein derived from human endogenous retrovirus clone 4-1 in autoimmune diseases.

To investigate whether human endogenous retroviruses (HERV) contribute to autoimmune diseases, we prepared a recombinant p30gag protein derived from clone 4-1 of the HERV family, using a baculovirus-vector system. This p30gag protein (CA41B) was approximately 30 kDa, as expected, and reacted with antibodies for p30gag purified from both murine and feline leukemia virus. This result suggested that the antigenic determinant for p30gag was well conserved in CA41B. Analysis of serum antibodies to p30gag in patients with autoimmune diseases was done by Western blotting. CA41B detected anti-p30gag antibodies in 48.3% of systemic lupus erythematosus (SLE) patients, 35.0% of Sjögren's syndrome (SS) patients, and 33.3% of mixed connective tissue disease (MCTD) patients, whereas no anti-p30gag antibodies were found in healthy subjects. This suggested that HERV p30gag or other retroviral p30gag proteins possessing the same antigenic determinant as CA41B may play a role in these diseases. Although detection of antibodies to HERV p30gag in autoimmune diseases is indirect evidence that HERV proteins are involved, this study showed that patients with autoimmune diseases have antibodies to HERV p30gag using a recombinant HERV protein rather than synthetic peptides based on HERV or retroviral proteins of other species.

Animals↗
PubMed1997

Structure and expression of carp mitogen-activated protein kinases homologous to mammalian JNK/SAPK.

Two distinct stress-activated protein kinase (JNKa and b) cDNAs were isolated from a carp ovary cDNA library. These cDNAs contained a full-length open reading frame encoding 427 amino acid residues with a predicted mass of 48.6 kDa. The deduced amino acid sequences of JNKa and b were 95.8% identical, with 18 residues replaced, and showed a high degree of sequence similarity to mammalian JNK/SAPK subgroup including the common dual phosphorylation motif of TPY. By Northern blot analysis, the carp JNKs were found to be abundant in the brain and ovary. Detailed study by RT-PCR assay revealed ubiquitous expression of JNKb, although expression of JNKa was specific to the brain and ovary. The high level expression of both JNKa and b in the ovary implies that JNKs play an important role in egg maturation or ectogenetic early development.

Amino Acid Sequence↗
PubMed1997

A rapid increase in foot tissue temperature predicts cardiovascular collapse during anaphylactic and anaphylactoid reactions.

BACKGROUND: Cardiovascular collapse during anaphylactic and anaphylactoid reactions results from release of histamine and other vasoactive substances. Intense arteriolar vasodilation associated with severe allergic reactions is likely to increase convective transfer of heat and peripheral tissue temperature, and finally to provoke cardiovascular collapse. Therefore the authors tested the hypothesis that during anaphylactic and anaphylactoid reactions, an acute increase in peripheral tissue temperature precedes cardiovascular collapse and that the magnitude of the increase correlates with the severity of the reaction. METHODS: During a 13-yr period, approximately 120,000 patients were screened for clinical evidence of intraoperative anaphylactic and anaphylactoid reactions. Core temperature was measured in the distal esophagus, and "deep" foot tissue temperature was measured on the sole of one foot in all these patients. Otherwise unexplained cardiovascular collapse accompanied by bronchospasm and/or cutaneous signs such as urticaria, flushing, or angioedema occurred in 32 patients who were entered into a prospective diagnostic protocol. Among these, 15 met laboratory criteria for anaphylactic or anaphylactoid reactions. Anaphylaxis was confirmed in nine of them by a positive skin test to the suspected agent, the in vitro leukocyte histamine-release test, or the Praunitz-Küstner test. Reactions were considered anaphylactoid in six others when laboratory evidence did not support anaphylaxis, but plasma histamine or tryptase concentrations were much greater during episodes than 6 weeks later. RESULTS: Development of anaphylactic and anaphylactoid reactions followed a characteristic pattern: (1) Foot temperature, which was initially 3.3 +/- 1.7 degrees C less than core temperature, increased to within 0.3 degrees C of core temperature 3.2 +/- 1.4 min after drug administration; (2) onset of cardiovascular collapse ensued 1.8 +/- 0.8 min later; and (3) core temperature increased from 34.7 +/- 1.0 degrees C to peak values 37.1 +/- 0.6 degrees C 13 +/- 5 min after drug administration. The most severe reactions were associated with shorter times to comparable core and foot temperatures, faster onset of cardiovascular collapse, and higher maximum core temperatures. CONCLUSIONS: The normal core-to-peripheral tissue temperature gradient was obliterated several minutes before hemodynamic consequences associated with anaphylactic and anaphylactoid reactions. Further, a rapid increase in deep foot temperature and maximum core temperature correlated with clinical severity.

Adolescent↗
PubMed1997

Polyarteritis nodosa associated with gastric carcinoma and hepatitis B virus infection.

Several cases of polyarteritis nodosa associated with malignant disorders have been reported, most with bone marrow-related tumors. We report polyarteritis nodosa presenting with a fever of unknown origin and muscle weakness that was complicated by advanced gastric carcinoma and hepatitis B virus-positive cirrhosis. Vasculitis was diagnosed after gastrectomy from histologic findings of arterial vasculitis on the resected gastric carcinoma. Our case is so far the second such report of polyarteritis nodosa associated with gastric cancer.

Hepatitis B↗
PubMed1997

Effects of daily alcohol intake on the blood pressure differ depending on an individual's sensitivity to alcohol: oriental flushing as a sign to stop drinking for health reasons.

OBJECTIVE: To determine whether flushing of the facial skin in response to alcohol consumption (alcohol flushing) is a warning sign of hypertension. We also sought the relationship between alcohol flushing and other risk factors that may contribute to the development of hypertension. METHODS: We first investigated the relationship of the aldehyde dehydrogenase 2 (ALDH2) genotype to alcohol flushing for 53 normal volunteers. We evaluated the relationships among hypertension, alcohol consumption, and facial flushing for 1011 middle-aged Japanese men (aged 40-68 years; mean 51.6 +/- 5.5 years), on the basis of their responses to questionnaires and health records. RESULTS: The first examination of 53 normal volunteers showed that there were differences in the degree of alcohol flushing between the ALDH2 genotypes (P < 0.01). Hypertension was observed in 27.4% of the study population (277 of 1011), and was correlated positively to alcohol consumption (P < 0.01). The prevalence of hypertension differed significantly among these four groups: there was a 22.4% prevalence (70 of 312) among subjects with no flushing, a 33.8% prevalence (113 of 334) among those with slight flushing, a 27% prevalence (84 of 311) among those with visible flushing, and an 18.5% prevalence (10 of 54) among subjects who were almost completely intolerant to alcohol (P < 0.05). In particular, heavy drinkers who consumed > or = 1.5 Go (a traditional Japanese unit equivalent to 27 g ethanol) a day had a high prevalence of hypertension with slight and visible skin flushing [42% (63 of 150) and 40.7% (24 of 59), respectively]. That a family history of hypertension, greater age, heavy alcohol consumption, obesity, and symptoms of intoxication including flushing were correlated significantly to the prevalence of hypertension for all groups was demonstrated by multiple logistic regression analysis (P < 0.05). CONCLUSIONS: A repeated heavy alcohol intake could increase the risk of hypertension for Japanese subjects who exhibit skin flushing in response to alcohol consumption. Chronic alcohol intake by subjects with alcohol flushing might bring about a significant increase in blood acetaldehyde levels and cause an additional rise in the blood pressure.

Adult↗
PubMed1997

Interlocking-clipping technique for giant aneurysms of the internal carotid artery: technical case report.

OBJECTIVE AND IMPORTANCE: Direct clipping of giant intracranial aneurysms is sometimes difficult. A unique technique using multiple fenestrated clips for closing a giant aneurysm is described. CLINICAL PRESENTATION: A 65-year-old woman presented with a 10-month history of headache and gait disturbance. Cerebral angiography disclosed an unruptured giant aneurysm of the right internal carotid artery. INTERVENTION: Surgical exposure confirmed the presence of a giant aneurysm with the splaying and incorporation of the parent artery and a number of perforating arteries originating from the dome. Four angled and three straight fenestrated clips were applied in tandem to the aneurysm to reconstruct the parent artery and preserve the perforating vessels. Through their blades and heads, the closely arranged clips were successfully interlocked. CONCLUSION: This "interlocking-clipping" technique is a modification of the tandem clipping technique. The aim of this approach is to enhance closing pressure and allow a more stable "seating" of the clips in giant cerebral aneurysms.

Aged↗
PubMed1997

Role of curdlan sulfate in the binding of HIV-1 gp120 to CD4 molecules and the production of gp120-mediated TNF-alpha.

To clarify the mechanism by which curdlan sulfate (CRDS) inhibits human immunodeficiency virus (HIV)-1 infection, we examined its influence on the binding of gp120 to CD4 molecules on T cells and macrophages, as well as on the production of TNF-alpha by gp120-stimulated macrophages (which promotes HIV-1 replication). CRDS treatment of cells not only inhibited the binding of HIV-1 gp120 to CD4+ cells, but also inhibited TNF-alpha production induced by gp120. Inhibition of HIV-1 infection by CRDS may be related to these two actions.

Anti-HIV Agents↗
PubMed1997

Expression of matrix metalloproteinase (gelatinase) in T1 adenocarcinoma of the lung.

The expression of matrix metalloproteinase-2 (MMP-2; 72 kDa type IV collagenase/gelatinase A) and MMP-9 (92 kDa type IV collagenase/gelatinase B) was immunohistochemically investigated in 79 T1 adenocarcinomas of the lung using non-commercial polyclonal anti-MMP-2 and -9 antibodies. Thirty-two (41%) and 22 (28%) among the 79 cases were positive in the tumor cells for MMP-2 and -9, respectively. The incidences of MMP-2 and -9 immunoreactivities were higher (64 and 45%, respectively) in poorly differentiated tumors than in well differentiated tumors (36 and 25%, respectively), and lower in bronchioloalveolar carcinoma (22 and 10%, respectively) compared with other subtypes of adenocarcinoma. The prognosis for patients with MMP-2 and/or -9 positive immunoreactivities was significantly poorer than for those with a MMP-negative tumor (P < 0.05). The degree of collagenization was divided into four grades, and tumors with a small to abundant amount of collagen (grade 2 and grade 3 fibrosis) had a higher incidence of immunoreactivity to both types of MMP. It is estimated that these expressions might be responsible for tumor invasion, metastasis, and for grade 2 and grade 3 fibrosis in T1 adenocarcinoma of the lung.

Adenocarcinoma↗
PubMed1997

Dedifferentiated liposarcoma with an inflammatory malignant fibrous histiocytoma-like component presenting a leukemoid reaction.

A rare case of dedifferentiated liposarcoma (well-differentiated liposarcoma with an inflammatory malignant fibrous histiocytoma (MFH)-like anaplastic component) occurring in a 69-year-old male is presented. The patient had noticed a dull pain in his left loin and thigh for about 1 month. Computed tomography examination revealed a low-density mass lesion, measuring about 6 cm in diameter, in the left iliopsoas muscle, and it was surgically removed. Grossly, the lesion was composed of an encapsulated, soft, whitish mass and an adjacent, well-demarcated, yellowish hard nodule, measuring about 2.5 cm in diameter. Microscopically, both lesions showed features of an inflammatory variant of MFH and a sclerosing type of well-differentiated liposarcoma, respectively. To our knowledge, only two cases of dedifferentiated liposarcoma combined with inflammatory MFH as a dedifferentiated component have been recorded in the literature. The salient feature of the present case is a systemic inflammatory reaction, as shown by prominent leukocytosis (up to 73,900/mm3) and the elevated serum value of C reactive protein (up to 26.0 mg/dL), which were transiently reduced after surgery. The inflammatory reaction was suggested to be induced by cytokines, such as granulocyte colony-stimulating factor and interleukin-6, which were probably produced by the tumor cells in the present case, because the elevated serum values of those cytokines were decreased after surgery.

Aged↗
PubMed1997

Nonlinear mathematical analysis of the hemodynamic parameters during left ventricular assistance with oscillated blood flow.

For the development of a totally implantable ventricular assist system (VAS), we have been developing the vibrating flow pump (VFP), which can generate oscillated blood flow with a relatively high frequency (10-50 Hz) for a totally implantable system. In this study, effects of left ventricular assistance with this unique oscillated blood flow were analyzed by nonlinear mathematics for evaluation as the entire circulatory regulatory system, not as a separate part of the system. Left heart bypasses using VFPs from the left atriums to the descending aortas were performed in chronic animal experiments using healthy adult goats. Electrocardiogram (ECG), arterial blood pressure, VFP pump flow, and flow of the descending aorta data taken while the goats were awake were recorded in the data recorder and analyzed in the personal computer system through the AD convertor. Using nonlinear mathematics, time series data were embedded into the phase space, and the Lyapunov numerical method, fractal dimension analysis, and power spectrum analysis were performed to evaluate the nonlinear dynamics. During left ventricular assistance with the VFP, Mayer wave fluctuations were decreased in the power spectrum, the fractal dimension of the hemodynamics was significantly decreased, and peripheral vascular resistance was significantly decreased. These results suggest that nonlinear dynamics, which mediate the cardiovascular dynamics, may be affected during LV bypass with oscillated flow. Decreased power of the Mayer wave in the spectrum caused the limit cycle attractor of the hemodynamics and decreased the peripheral resistance. Decreased sympathetic discharges may be the origin of the decreased Mayer wave and fractal dimension. These nonlinear dynamical analyses may be useful to design the optimal VAS control.

Animals↗
PubMed1997

Hemolysis test of disposable type vibrating flow pump.

The vibrating flow pump (VFP) can generate high frequency oscillated blood flow. Because of the high frequency driving with short stroke volume, the pump system can be small. The disposable type VFP (D-VFP) was developed for use for extracorporeal circulation. The electromagnetic actuator was detached from the vibrating tube, which was newly designed to be a disposable tube with a jellyfish valve. Hemolysis tests of the D-VFP, VFP, centrifugal pump, and roller pump were performed in a mock circulation study using goat blood. Plasma free hemoglobin was measured every 15 min under the same conditions. The plasma free hemoglobin of the D-VFP was 16 mg/dl although that of the VFP was 160 mg/dl at 30 min. The plasma free hemoglobin of the centrifugal pump and roller pump at 30 min were 3 mg/dl and 9 mg/dl, respectively. The hemolysis performance of the D-VFP may be studied further as a result of this study. Two important factors affecting hemolysis development may be the materials of which the vibrating tube is made and heat transmission from the actuator. The D-VFP has a smooth acrylic surface for blood contact compared with the metal surface of old type VFP. The electromagnetic actuator of the VFP surrounded the vibrating tube, so heat from the actuator could be easily transmitted to the blood. Because the D-VFP has a disposable vibrating tube that is detached from the actuator, heat is not readily transmitted to the blood. A mock circulation study of heat transmission was performed using the D-VFP and VFP. Results of the heat transmission study showed that the fluid temperature of the D-VFP was not increased and stayed at room temperature although that of the VFP increased approximately 1 degree C above room temperature. The D-VFP may be a good style for the development of the VFP for use for extracorporeal circulation.

Acrylates↗
PubMed1997

Pulmonary arterial impedance analysis by the use of the oscillated assist flow.

Pulmonary arterial impedance is an important and interesting characteristic that can be used to evaluate the physiological properties of the pulmonary vessel. However, power spectrum analysis of the pulmonary artery pressure and flow pattern have suggested that peak power in the relatively high frequency range (> 10 Hz) is significantly low; thus, we cannot analyze the vessel properties in the high frequency range. In this study, we used the newly developed vibrating flow pump (VFP), which can generate oscillated blood flow with a relatively high frequency (10-50 Hz) for right heart bypass, to evaluate the pulmonary arterial impedance pattern in the high frequency range. Acute animal experiments of the right heart bypass from the right atrium to the pulmonary artery using 6 healthy adult goats were performed. The flow pattern and pressure of the pulmonary artery, electrocardiograms (ECGs), and arterial and right atrial pressures were continuously monitored during the experiments. Spectral analysis of the hemodynamic parameters using the fast Fourier transform (FFT) method was performed to evaluate the spectral properties. The coherence function, transfer function, and phase patterns were calculated to analyze the impedance pattern in the relatively high frequency area. Previously, various investigators had tried to analyze the impedance patterns of the pulmonary artery; however, they could not analyze the impedance patterns over 10 Hz because the spectral patterns of the pulmonary flow do not have high power at high frequencies. These physiological analyses may be useful in designing the optimal pulmonary circulation.

Animals↗
PubMed1997

Growth hormone does not affect non-insulin-mediated glucose uptake in sheep.

Four adult Merino sheep were used in the experiment, which was divided into four parts. For the 5 days before parts 1 and 3 saline was injected and for the 5 days before parts 2 and 4 growth hormone (GH; 4 mg day-1 subcutaneously) was injected. In parts 1 and 2 a primed continuous infusion of [6,6-2H2]glucose and either saline or GH, respectively, were infused for 5 h. The first 3 h was the control period. From 3 to 5 h insulin (0.5 mU kg-1 min-1) was infused. Coincident with the insulin infusion, normal glucose was also infused at a variable rate, dependent on the rapidly determined plasma glucose concentration, in order to keep the plasma glucose concentration constant. Parts 3 and 4 of the experiment were the same as parts 1 and 2, respectively, except for the following: the glucose isotope and saline or GH were infused for 7 h, from 3 to 7 h somatostatin (SRIF; 0.417 microgram kg-1 min-1) was infused, and from 5 to 7 h insulin was infused. Measurements of glucose turnover were made in the last 40 min of the control, insulin-only, SRIF-only and insulin-plus-SRIF infusion periods. Plasma insulin levels were reduced to below the level of detection by the SRIF infusion; under such conditions whole body glucose uptake should be entirely non-insulin mediated (NIMGU). Expressing glucose uptake as glucose metabolic clearance rate revealed that GH had no effect on NIMGU but significantly reduced the level of insulin-mediated glucose uptake (IMGU). Thus a reduction in the rate of NIMGU is probably not part of the mechanism by which GH repartitions glucose to sites of growth and milk production, whilst the present study confirms the antagonistic effect of GH on IMGU.

Animals↗
PubMed1997

Vasoactive intestinal polypeptide and pituitary adenylate cyclase-activating polypeptide receptor chimeras reveal domains that determine specificity of vasoactive intestinal polypeptide binding and activation.

Vasoactive intestinal polypeptide (VIP) and pituitary adenylate cyclase-activating polypeptide (PACAP) receptors are closely related G protein-coupled receptors with seven-transmembrane domains. The VIP receptor can bind both VIP and PACAP with high affinity, whereas the PACAP receptor binds only PACAP with high affinity. To elucidate the structural domains involved in a selectivity for VIP binding and the subsequent receptor activation, a series of chimeric receptors between the VIP and PACAP receptors was constructed, expressed in COS-7 cells, and analyzed for ligand binding and cAMP generation. All chimeric constructs bound PACAP with high affinity and subsequently activated cAMP generation similarly to the wild-type receptors. In contrast, profound differences were observed in the potencies of VIP for competition of 125I-labeled PACAP binding to both wild-type receptors and the chimeric receptors. The cAMP responses of these receptors generally correlated with the ability of VIP to compete for PACAP radioligand binding with the exceptions for some particular chimeras. In this report we demonstrate that several domains, including the amino-terminal extracellular domain, the transmembrane domains I and II, and the first extracellular loop of the VIP receptor, are important for the selectivity for VIP binding and responsiveness to VIP. We further show that the third extracellular loop and its proximal domains of the VIP receptor appear to be involved in the VIP recognition, especially the receptor activation process. On the other hand, the direct binding experiments of the VIP radioligand demonstrated that both wild-type receptors and all chimeric receptors have a high affinity binding site for VIP, although this high affinity VIP binding resulted in a biological response only in the VIP receptor or VIP receptor-like chimeras. This suggests that there is a nonbiologically relevant high affinity VIP-binding site within the rat PACAP receptor.

Amino Acid Sequence↗
PubMed1997

Human immunodeficiency virus type 2 envelope glycoprotein binds to CD8 as well as to CD4 molecules on human T cells.

We report here that human immunodeficiency virus type 2 (HIV-2) envelope glycoprotein (gp105), but not HIV-1 gp120, can bind to CD8 molecules as well as to CD4 molecules on human T cells. This phenomenon may lead to differences in the life cycles of HIV-1 and HIV-2, and it may be related to the differences in disease manifestations of HIV-1 and HIV-2 infection, including longer survival of HIV-2-infected patients.

CD4 Antigens↗