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H Hashimoto

Publications and source records attributed to H Hashimoto.

At least 523 records · Page 29Linked to original sources
PubMed1996

Involvement of Na+-Ca2+ exchanger in reperfusion-induced delayed cell death of cultured rat astrocytes.

In some cells, Ca2+ depletion induces an increase in intracellular Ca2+ ([Ca2+]i) after reperfusion with Ca2+-containing solution, but the mechanism for the reperfusion injury is not fully elucidated. Using an antisense strategy we studied the role of the Na+-Ca2+ exchanger in reperfusion injury in cultured rat astrocytes. When astrocytes were perfused in Ca2+-free medium for 15-60 min, a persistent increase in [Ca2+]i was observed immediately after reperfusion with Ca2+-containing medium, and the number of surviving cells decreased 3-5 days later. The increase in [Ca2+]i was enhanced by low extracellular Na+ ([Na+]0) during reperfusion and blocked by the inhibitors of the Na+-Ca2+ exchanger amiloride and 3, 4-dichlorobenzamil, but not by the Ca2+ channel antagonists nifedipine, Ca2+ and Ni2+. Treatment of astrocytes with antisense, but not sense, oligodeoxynucleotide to the Na+-Ca2+ exchanger decreased Na+-Ca2+ exchanger protein level and exchange activity. The antisense oligomer attenuated reperfusion-induced increase in [Ca2+]i and cell toxicity. The Na+-Ca2+ exchange inhibitors 3, 4-dichlorobenzamil and ascorbic acid protected astrocytes from reperfusion injury partially, while the stimulators sodium nitroprusside and 8-bromo-cyclic GMP and low [Na+]0 exacerbated the injury. Pretreatment of astrocytes with ouabain and monensin caused similar delayed glial cell death. These findings suggest that Ca2+ entry via the Na+-Ca2+ exchanger plays an important role in reperfusion-induced delayed glial cell death.

Amiloride↗
PubMed1996

Frontonasal flap for reconstruction of complete alar defects.

BACKGROUND: It is difficult to reconstruct a satisfactory ala. Axial frontonasal flap has been common in reconstruction of nasal tip. We modified this flap to reconstruct nasal ala. OBJECTIVE: A modified axial frontonasal flap was applied for reconstruction of complete unilateral alar defects in two patients. METHODS: Skin from an intact nasal tip covered the alar defect. The resulting defect in the nasal tip was covered with dorsal skin from the nose. Extended mucosa or a hinged nasolabial flap was used to line the mucosal side of the reconstructed ala. RESULTS: The outcome judged by shape, and texture, was satisfactory. This technique can be employed under field block. CONCLUSION: The modified frontonasal flap is one of the ideal techniques to reconstruct an entire nasal ala.

Aged↗
PubMed1996

Ossifying epithelioid hemangioendothelioma.

A case of small epithelioid hemangioendothelioma encapsulated by an egg-shaped bony shell composed of newly formed mature lamellar bone is presented. A nodule measuring 10 x 5 x 5 mm was excised from inside of the right cheek muscle of a 46-year-old man. Histopathologically, the nodule consisted mainly of round-to-short spindled epithelioid cells with round nuclei and occasional cytoplasmic vacuoles associated with some foci of osseous metaplasia. Characteristically, egg shell-like lamellar bone enclosed this lesion showing well-circumscribed appearance. The main component cells were immunohistochemically stained positive for factor VIII-related antigen, CD 34, UEA-1, and vimentin, and proved to be vascular endothelial cells. The term ossifying epithelioid hemangioendothelioma is proposed for this unique lesion. This type of epithelioid hemangioendothelioma has not been previously reported to our knowledge, and differentiation from ossifying fibromyxoid tumor of soft parts is considered to be important.

Cheek↗
PubMed1996

Immunoelectron microscopy of corticotropes and melanotropes in the pituitary gland of the European ferret, Mustela putorius furo.

The superimposition technique and protein A-gold method of immunoelectron microscopy were employed to study the ultrastructure of corticotropes as well as melanotropes in the ferret pituitary gland. This is the first study ever elucidating the ultrastructural heterogeneity of melanotropes in mammalian pars intermedia on an immunocytochemical basis. Morphological heterogeneity of pars distalis corticotropes has also been elucidated. It is suggested that the different subtypes may represent stages of development (histogenesis), or functional phases of a single cell type. In addition, the occurrence and distribution of both corticotropes and melanotropes in different hypophyseal components have been studied by light-microscopic immunocytochemistry.

Adrenocorticotropic Hormone↗
PubMed1996

Fluoride at mitogenic concentrations increases the steady state phosphotyrosyl phosphorylation level of cellular proteins in human bone cells.

This study was designed to test the hypothesis that treatment of human bone cells with mitogenic concentrations of fluoride would lead to an increase in the steady state level of tyrosyl phosphorylation of specific cellular proteins. With an immunoblot assay method, it was found that mitogenic concentrations of fluoride (i.e. 50-200 mumol/L) induced a dose- and time-dependent increase in the level of tyrosyl phosphorylation of at least 13 cellular proteins in both normal human bone cells and human TE85 osteosarcoma cells. Time-course studies revealed that a statistically significant increase in tyrosyl phosphorylation of these 13 cellular proteins in human bone cells was observed after 3-6 h of fluoride treatment and was sustained for up to 24 h. This time course was not compatible with a direct activation of tyrosyl kinases, as epidermal growth factor, which activates tyrosyl kinase activity, induced an immediate and acute response that was rapidly reversible within 1 h. Although fluoride increased the steady state tyrosyl phosphorylation of the cellular proteins in human bone cells, the same micromolar doses of fluoride had no effect on human skin fibroblasts, which are fluoride-nonresponsive cells. The effects of fluoride were rapidly reversible in the absence of fluoride and could be acutely potentiated by pretreatment with epidermal growth factor. In summary, we have shown for the first time that mitogenic concentrations (i.e. 50-200 mumol/L) of fluoride increased the steady state level of tyrosyl phosphorylation of at least 13 cellular proteins in human bone cells, and that the increases were relatively show in onset and sustained. In conclusion, these findings are consistent with the hypothesis that the osteogenic actions of fluoride are mediated at least in part by an inhibition of the activity of one or more fluoride-sensitive phosphotyrosyl protein phosphatases in human bone cells.

Bone and Bones↗
PubMed1996

Participation of GTP-binding protein in the photo-transduction of Paramecium bursaria.

Analysis of the flow of light information in Paramecium, especially the participation of GTP-binding protein, was carried out. Injection of GDP-beta-S into Paramecium cell abolished the light-induced inward current. The partially purified rhodopsin-like protein (RLP) that we obtained activated frog rod outer segments (ROS) GTPase. A GTP-binding protein, with Mw 57,000 was detected by immunostaining with anti-rat G alpha rabbit IgG. These results suggest that the light information flows from the light-captured RLP to the GTP-binding protein.

Animals↗
PubMed1996

Comparison of aortic valve replacement and percutaneous aortic balloon valvuloplasty for elderly patients with aortic stenosis.

The outcome of aortic balloon valvuloplasty (ABV) was compared with that of aortic valve replacement (AVR) in aortic stenosis (AS) patients more than 60 years old. The indications for ABV included low respiratory and renal function, cancer, the patient's refusal of surgery, and low daily activity. Twenty six patients underwent AVR and 13 underwent ABV. Initially, the AVR group was younger and more symptomatic than the ABV group. Two perioperative deaths occurred in the AVR group, while there were none in the ABV group. Twenty-four AVR patients and 12 ABV patients had a successful outcome, with remarkable pressure gradient reduction in both groups. In the follow-up, only 1 death and no cardiac events were detected in the AVR group (mean follow-up of 27 months), whereas 3 deaths, 6 heart failures, 2 repeated ABV, and 4 AVR were seen in the ABV group (mean follow-up of 10 months). The data showed that ABV was safer than AVR, but a higher rate of restenosis limited its efficacy. In the ABV group, a higher ratio of balloon size to aortic diameter correlated with longer event-free survival. We concluded that for elderly AS patients, ABV should be used only in those with high surgical risk as a palliative therapy or a bridge therapy to AVR, and AVR should be primarily recommended under rigid evaluation of the patient's physical status.

Aged↗
PubMed1996

Expression of 135-kDa insecticidal protein gene from Bacillus thuringiensis in the yeast Saccharomyces cerevisiae.

Bacillus thuringiensis subsp. aizawai produces 130-kDa and 135-kDa (CryIA(a)) insecticidal proteins. When Saccharomyces cerevisiae was transformed by the vector carrying a cryIA(a) gene, the gene expression could not be observed. When the 5'-upstream region from the initiation codon was removed using a synthetic oligonucleotide, the CryIA(a) protein was successfully synthesized in yeast. The yeast extract containing CryIA(a) protein had insecticidal activity against Plutella xylostella larvae.

Bacillus thuringiensis↗
PubMed1996

The relationship between serum levels of interleukin-6 and thyroid hormone during the follow-up study in children with nonthyroidal illness: marked inverse correlation in Kawasaki and infectious disease.

Our previous study demonstrated that the serum IL-6 correlated inversely with serum T3 and the T3/T4 ratio in children with acute respiratory infection during the acute phase of illness. To investigate whether serum IL-6 inversely correlates with serum thyroid hormone during not only the active stage of the disease but also in the follow-up period in nonthyroidal illness, we measured serum levels of IL-6, T3 and T4 in 31 children from the acute to the convalescent phase. They were divided into 3 groups; 7 patients with Kawasaki disease, 16 patients with infectious disease and 8 patients with non-inflammatory disease. In the follow-up of patients with Kawasaki disease, a marked inverse relationship was observed between serum IL-6 and T3 (r = -0.844, P < 0.001) or the T3/T4 ratio (r = -0.863, P < 0.001). Serum T4 showed a weak but significant negative correlation with serum IL-6 (r = -0.474, P = 0.035) only in this situation. There was also a significant negative correlation between serum IL-6 and T3 (r = -0.582, P < 0.001) or the T3/T4 ratio (r = -0.660, P < 0.001) during the follow-up of children with infectious disease. In the follow-up study of patients with non-inflammatory disease, however, no significant relationships were observed between serum thyroid hormones and IL-6. IL-6 may be one important factor involved in the decrease in the serum T3 level and the T3/T4 ratio in patients with nonthyroidal illness particularly characterized by strong inflammation and activation of the immune system as observed in Kawasaki and infectious disease.

Adolescent↗
PubMed1996

The expression of lymphocyte function associated antigen-1, intercellular adhesion molecule-1 on peripheral blood lymphocytes in patients with systemic lupus erythematosus.

The ratios of CD11a, CD18, HLA-DP on T cells and CD54 on B cells of 54 patients with active systemic lupus erythematosus (SLE) were examined. The ratios of LFA-1 alpha, beta, ICAM-1, HLA-DP among SLE patients were significantly higher when compared with normal healthy controls, and the significant correlation between the ratio of LFA-1+ T cells and HLA-DP+ T cells, and LFA-1+ T cells and ICAM-1+ B cells was recognized. These results may suggest that LFA-1, ICAM-1 is related to the mutual action between activated T cells and B cells.

Adolescent↗
PubMed1996

[Non-specific neurological complaints and silent cerebral infarction].

To clarify the relationship between non-specific neurological complaints and silent cerebral infarction (SCI), we studied 82 patients (56 +/- 8 years old; mean +/- SD) who presented with at least one complaint (headache, dizziness, forgetfulness) and 76 normal volunteers with no complaints (55 +/- 7 years old). All subjects were evaluated with a questionnaire for complaints and with 0.5 T magnetic resonance imaging of the brain for the presence of SCI. Several risk factors for stroke were also studied. SCI was significantly more common in the patients (18%) than in the normal subjects (7%, p < 0.05). SCI was more common in subjects with dizziness (40%) and in those with headache (18%) than in those with no complaints (p < 0.01, p < 0.05, respectively). Dizziness and forgetfulness were closely associated with SCI (p < 0.05). Two risk factors for stroke, age and hypertension, correlated with SCI. These results clearly show that non-specific neurological complaints are closely related to SCI.

Aged↗
PubMed1996

[Clinical and pathological study of gastric cancer treated without surgery in elderly patients].

OBJECTIVE: To clarify the clinical and pathological characteristics of gastric cancer in the elderly. METHOD: Clinical and pathological characteristics of patients who died during 1986-94 with gastric cancer which did not undergo surgery were studied retrospectively. The patients were divided into three groups according to age: A (65-74 years, n = 38), B (75-84 years, n = 77), and C (85 years and over, n = 43). RESULTS: Borrman type-1 was more frequent in group C and Borrman type-4 was frequent in group B. "Early cancer", protruded type (type I or type IIa) was more frequent in group C. In cases of advanced cancer some patients did not undergo surgery because the cancer was to advanced, and others had concomitant diseases that made surgery risky. In all groups, a few patients refused surgery. In cases of "early cancer", the most reason for not undergoing surgery was a concomitant disease in all groups. Other reasons were general weakness and dementia in group C, second malignancy and dementia in group B, and second malignancy in group A. After advanced cancer was diagnosed, 9.6% survived for 1 year, and 1.7% for 2 years. After early cancer was diagnosed, 50.7% survived for 1 year, 15.2% for 3 years and 7.8% for 4 years. The survival rates did not differ by age. In all age groups, gastric cancer was frequently the main cause of death in patients with advanced cancer, but many patients with "early cancer" died of other causes.

Age Factors↗
PubMed1996

Effect of administration of milk fermented with Lactobacillus acidophilus LA-2 on fecal mutagenicity and microflora in the human intestine.

To demonstrate the antimutagenic effect of fermented milk in the human intestine, fecal mutagenicity and bacterial composition of six healthy subjects consuming their regular diet were investigated before and during the administration of milk fermented with Lactobacillus acidophilus LA-2. The administration of the fermented milk caused a remarkable decrease (71.9% on the average; range of 19.4 to 90.6%) in fecal mutagenicity compared with that before the administration; Lactobacillus spp. and Bifidobacterium spp. population increased in the feces of all subjects. The suppression of fecal mutagenicity appeared to be due to the change in fecal microflora caused by the presence of strain LA-2 in the human intestine.

Adult↗
PubMed1996

Effects of aminobenzoic acid derivatives with 4-AET/HEMA in self-etching primer on bonding to ground dentin.

The effect of the inclusion of aminobenzoic acid derivatives (ABAD) in a self-etching primer comprising 4-acryloxyethyltrimellitic acid (4-AET), HEMA and water on shear bond strength to ground dentin was investigated. The mean bond strengths to dentin were significantly increased by the inclusion of 0.307 mol% ABAD in the 4-AET/HEMA primer, when compared with the control (0 wt% ABAD) (p < 0.01). A particularly high value (38.0 MPa) of shear bond strength was obtained in the use of the primer containing p-nitroanthranilic acid (p-NAA). It seemed to assume that the effect of p-NAA could be caused by the strong electron-withdrawing group of -NO2. From SEM observation, it was found that bonding resin appeared to adhere strongly to the ground dentin without formation of any resin-tags in the dentinal tubules. It was thought that the ABAD with 4-AET/HEMA could perform facilitating photo-polymerization at the bonding interface, and resulted in increased bond strength to ground dentin, and that the bond strength could be affected by the electronegativities of substitutional groups of ABAD.

4-Aminobenzoic Acid↗
PubMed1996

Effects of radical polymerizable spirocyclic monomers with new polymerization initiator systems on adhesion.

To develop a non-polymerization shrinkage adhesive resin, the effects of the contents varying 0-20 wt% radical polymerizable spirocyclic monomers of 2-methylene-1, 4, 6-trioxyaspiro [4, 6] undecane (MTSU) and 2-methylene-8, 9-benzo-1, 4, 6 trioxyaspiro [4, 4] nonane (BTSN) together with three kinds of initiator systems in adhesive resin on bonding to both Ni-Cr alloy and unetched enamel were investigated. Tensile bond strength to either Ni-Cr alloy or unetched enamel was affected by the inclusion of MTSU or BTSN, and indicated that increased contents of MTSU or BTSN resulted in decreased bond strength to the metal in the negative correlations. Regarding the bond strength to Ni-Cr alloy, however, the effective concentration of BTSN was found to be 5 wt%, and the mean bond strength was 58.5 and 58.6 MPa, respectively. The data of differential scanning calorimeter measurement, on the other hand, showed that the copolymerization of MTSU with conventional methacrylate monomers was not completely achieved.

Adhesiveness↗