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H Tada

Publications and source records attributed to H Tada.

At least 217 records · Page 12Linked to original sources
PubMed1996

Characterization of novel secreted and membrane proteins isolated by the signal sequence trap method.

We recently described a method, called the signal sequence trap (SST) method, to clone cDNAs of secreted proteins and/or type I transmembrane proteins containing N-terminal signal sequences by using an epitope-tagging expression plasmid vector. In this paper we describe the summary of a large-scale screening of approximately 5900 clones of an SST cDNA library constructed from mouse bone marrow stromal cell line ST-2 cells. Of 26 positive clones obtained and sequenced, 11 clones appeared to contain authentic signal sequences. Five of the clones corresponded to the 5' ends of the cDNA of known genes containing N-terminal signal sequences. The full-length cDNA clones of the 6 other unknown clones were isolated and sequenced. One clone, termed SDF3, encoded a mouse counterpart of human pigment epithelium-derived factor. Another clone, termed SDR1, had considerable homology with basigin, a member of the immunoglobulin superfamily. A third clone, termed SDF5, had partial homology with a Drosophila tissue polarity gene frizzled (fz) and its rat homologues, fz-1 and fz-2. The other three clones had no significant homology with sequences in the databases. These results indicate that the SST method is effective and useful for the isolation of secreted and membrane proteins without knowledge of their functions.

Amino Acid Sequence↗
PubMed1996

Isolation and characterization of a novel secretory protein, stromal cell-derived factor-2 (SDF-2) using the signal sequence trap method.

With use of the signal sequence trap method, we isolated a cDNA encoding a novel secretory protein, SDF-2, from the mouse stromal cell line, ST2. The human homologue of SDF-2 was also isolated. The amino acid (aa) sequences deduced from both the clones were conserved more than 92%. The chromosomal localization of the human SDF-2 gene was mapped to 17q11.2. The aa sequence of SDF-2 shows similarity to those of yeast dolichyl phosphate-D-mannose:protein mannosyltransferases, Pmt1p [Strahl-Bolsinger et al. (1993) Proc. Natl. Acad. Sci. USA 90, 8164-8168] and Pmt2p [Lussier et al. (1995) J. Biol. Chem. 270, 2770-2775], whose activities have not been detected in higher eukaryotes.

Amino Acid Sequence↗
PubMed1996

Usefulness of electron-beam computed tomography in arrhythmogenic right ventricular dysplasia. Relationship to electrophysiological abnormalities and left ventricular involvement.

BACKGROUND: Electron-beam computed tomography (CT) may be useful for detecting myocardial fat infiltration and diagnosing arrhythmogenic right ventricular dysplasia (ARVD). There are several characteristic electron-beam CT findings of ARVD. However, the incidence, their relation to electrophysiological abnormalities, and the usefulness of electron-beam CT for evaluating left ventricular involvement are unknown. This study aimed to clarify these issues. METHODS AND RESULTS: Electron-beam CT was performed in 14 patients with ARVD (ARVD group), 16 age- and sex-matched patients with right ventricular enlargement and/or dysfunction without ARVD (RV enlargement group), and 13 control subjects (control group). The incidences of abnormal electron-beam CT findings in the three groups were examined. Furthermore, we examined the endocardial fat-infiltrated areas detected by electron-beam CT (CT-A) and electrophysiologically abnormal areas detected in the mapping electrophysiology study (EPS-A) and compared the relationship between them in the ARVD group. (1) The frequencies of abundant epicardial adipose tissue, low-attenuation trabeculations, scalloping of the right ventricular free wall, and intramyocardial fat deposits were 86%, 71%, 79%, and 50%, respectively, in the ARVD group, whereas these findings were not observed in the RV enlargement and control groups. (2) Three ARVD patients (21%) had adipose tissue involvement of the left ventricle. (3) The relationship between CT-A and EPS-A was as follows: CT-A > EPS-A, 71%; CT-A = EPS-A, 14%; and EPS-A only, 14%. CONCLUSIONS: Characteristic electron-beam CT findings are frequently observed only in patients with ARVD. Electron-beam CT is useful for evaluating for left ventricular involvement and can estimate EPS-A.

Adult↗
PubMed1996

Ischemic colitis during interferon-alpha treatment for chronic active hepatitis C.

Between 1991 and 1994, at Hoshigaoka Koseinenkin Hospital, we treated 280 patients with chronic hepatitis C with interferon (IFN), and ischemic colitis occurred in two patients (0.7%) during the treatment. Melena appeared in case 1 in the 2nd month after the initiation of IFN-alpha treatment, and in case 2 in the 6th month. In both patients, longitudinal ulcerations in the descending colon were revealed by urgent colonoscopy, and these resolved within 2 weeks after discontinuation of the IFN treatment. It appears that ischemic colitis was associated with the IFN treatment, suggesting that attention should be paid to this possible complication.

Aged↗
PubMed1996

Side effects of high-dose interferon therapy for chronic hepatitis C.

BACKGROUND/AIMS: Various side effects have been reported in patients treated with alpha interferon, but their incidence and prognosis remain unknown. METHODS: Nine hundred and eighty-seven patients with chronic active hepatitis C received 6 to 10 MU of alpha interferon per day for 2 weeks and 3 times per week for 22 weeks. Autoantibodies, thyroid function tests, and fasting plasma glucose concentrations were evaluated prior to alpha interferon therapy. RESULTS: Of the 987 patients, 310 were required reduction in the dose of alpha interferon to 3 MU/day or cessation of alpha interferon therapy because of adverse reactions such as flu-like symptoms, leukopenia, and thrombocytopenia. Of the remaining 677, five developed diabetes mellitus, 12 had hyperthyroidism, and six acquired hypothyroidism. Of the 18 with thyroid disorders, five demonstrated antimicrosomal antibodies before therapy. Forty-four patients revealed high or low concentrations of thyroid stimulating hormone at the end of alpha interferon therapy. Three patients developed interstitial pneumonia, one acquired systemic lupus erythematosus-like syndrome, two had autoimmune hepatitis, two developed rheumatoid arthritis, and one developed autoimmune thrombocytopenic purpura. No patients had a history of an autoimmune disorder. One patient experienced sudden hearing impairment and one had retinal detachment. Melena was seen in three patients; two of these cases were compatible with ischemic colitis. Symptoms of depression were seen in 23 patients, and one patient manifested memory loss. CONCLUSION: High-dose alpha interferon therapy induces various adverse effects. Most of the side effects cannot be predicted, but are reversible.

Adult↗
PubMed1996

Onset of Graves' thyrotoxicosis after an attack of allergic rhinitis.

We previously reported that allergic rhinitis was an aggravating factor for Graves' disease and that thyrotoxicosis relapsed 2 months after an allergic attack. In this paper, we report a patient who showed onset of Graves' thyrotoxicosis after an attack of allergic rhinitis. The patient, a 30-year-old woman, was initially diagnosed with subclinical autoimmune thyroiditis. Interestingly, the patient showed weak activity of thyroid-stimulating antibody (TSAb), while TSH-binding inhibitory immunoglobulin (TBII) was negative and her thyroid function tests, including TSH, were completely normal. The patient developed severe allergic rhinitis in response to Japanese cedar pollen lasting from February until April in 1995 with an increase in serum antigen-specific immunoglobulin E and peripheral blood eosinophils. Two months later, she developed thyrotoxicosis in association with increase in TSAb and TBII. These findings suggest that allergic rhinitis not only aggravates Graves' disease but also induces the clinical onset of Graves' thyrotoxicosis.

Adult↗
PubMed1996

Predictive factors of a response to interferon therapy in chronic hepatitis C.

To determine predictive factors of response to interferon (IFN) therapy in chronic hepatitis C patients, we administered IFN-alpha, 1 6 million U1 intramuscularly daily for 2 consecutive weeks, then three times a week, to 136 patients judged to have chronic hepatitis C virus (HCV) infection according to HCV-RNA positivity. We also investigated the most effective length of IFN-alpha treatment according to efficacy factors, i.e., histological activity index. HCV-RNA genotype, and HCV-RNA levels. patients were classified either into a short-term group (entire treatment period 16 weeks), standard-term group (24 weeks), and long-term group (40 weeks). Patients were assessed as complete responders (CR) if their HCV-RNA became negative and their alanine aminotransferase (ALT) decreased to < or = 39 IU/L after 18 months of treatment or nonresponders in other cases. Results showed that HCV-RNA levels and genotype were statistically significant predictive factors. CR rates in the standard- and long-term groups were significantly higher than in the short-term group (p < 0.05). In patients with low HAI scores, the long-term group showed the highest CR rate. In patients with low virus counts, the CR rate increased to 73% in the 24th week and 100% in the 40th week. CR rates in patients with HCV-RNA genotype 1b and 2a or 2b also increased as the treatment period became longer. For efficacy, a 24-week treatment period was necessary. In patients with mild liver tissue damage or low virus counts, 40 weeks of treatment proved highly useful.

Adult↗
PubMed1996

Induction of the low-molecular-weight stress protein HSP27 in organ-cultured normal human skin.

To examine the inducibility of 27-kD-molecular-weight heat shock protein (HSP27) in human skin, an indirect immunofluorescence (IF) study was performed on organ-cultured normal human skin by using a monoclonal antibody specific for HSP27. After heat treatment at 45 degrees C for 1 h, nuclear IF was observed in the epidermal cells. When the organ-cultured skin explants were exposed to 10.0 micrograms/ml or 100.0 micrograms/ml 8-methoxypsoralen (8-MOP) for 1 h and then irradiated with UVA (320-400 nm), positive nuclear IF was also observed 6 h after UVA irradiation. Considering these results with the previous reports about HSP72, it appears that, in human skin, HSP27 as well as HSP72 plays an important role in resisting various environmental stresses.

Aged↗
PubMed1996

Expression of E-cadherin in skin carcinomas.

In this study, we investigated the expression of E-cadherin in 31 cases of human skin carcinoma including basal cell carcinoma (BCC), squamous cell carcinoma (SCC), Paget's disease, Bowen's disease (invasive type), and trichilemmal carcinoma, by immunohistochemical staining using a monoclonal antibody specific for E-cadherin. Similar to the E-cadherin expression in normal epidermis, E-cadherin was strongly expressed in all samples of BCC on the cell borders, whereas marked decrease or loss of E-cadherin expression was found in the tumor cells of SCC, Paget's disease, and Bowen's disease (invasive type). On the other hand, E-cadherin expression of trichilemmal carcinoma was slightly reduced. Considering the clinical and histological features of these skin carcinoma, the reduction of E-cadherin expression is considered to be associated with the invasion and metastasis of human skin carcinoma.

Adult↗
PubMed1996

Bullous pemphigoid associated with internal malignancies: identification of 180-kDa antigen by western immunoblotting.

We report three cases of bullous pemphigoid associated with internal malignancies. Two cases were associated with gastric cancer and one with rectal cancer. Immunoblot analysis, using epidermal extract of normal human skin, revealed that these patients' sera reacted only with bullous pemphigoid antigen with a molecular weight of 180 kDa (BP180). The relationship of BP180 to malignant tumours is discussed.

Adenocarcinoma↗
PubMed1996

Application of sweet potato fiber to skin wound in rat.

In order to introduce a suitable drug mixing base or covering for burns or decubital wounds, the usefulness of fiber extracted from the sweet potato was investigated. The healing effect of the fiber was evaluated by examining the extent of reduction in the size of wounds and changes in the quality of wounds in rats. In contrast to the control, the use of the fiber alone as a wound covering material reduced wounded areas by 21.0% at postoperative day 9, 19.5% at day 11, and 18.7% at day 13, and resulted in an obvious increase in the rats' weight. The number of days required for healing in all treated rats was 19 for the fiber groups and over 21 d for the control. In vitro, the fiber indicated excellent absorptive ability for serum and good adhesive ability for a number of proteins. This result suggested that the fiber has favorable properties for healing wounds which contain large amounts of exudate. Our macroscopic findings also indicated that the fiber protected wounds from dryness. These results suggested that sweet potato fiber could be use as a covering material in combination with drugs in skin wound therapy.

Absorption↗
PubMed1996

Sudden death in a patient with apparent idiopathic ventricular tachycardia.

Idiopathic ventricular tachycardia is widely believed to carry a favorable prognosis, although there have also been reports of sudden cardiac deaths. We present a case of sudden death in a patient with apparent idiopathic right ventricular tachycardia. This patient had long-standing and exercise-related symptoms, an essentially negative non-invasive cardiac evaluation, and spontaneous and inducible ventricular tachycardia of left bundle branch block and inferior axis morphology, that was treated with propranolol. After an uneventful 5-year course, the patient died suddenly. Postmortem examination revealed a severely dilated right ventricle and significant replacement of the right ventricular wall with adipose tissue. Interstitial fibrosis was also seen, but only to a very slight degree.

Bundle-Branch Block↗
PubMed1996

Human betacellulin, a member of the EGF family dominantly expressed in pancreas and small intestine, is fully active in a monomeric form.

Betacellulin (BTC) was found to be expressed mainly in human pancreas and small intestine. This finding suggests that BTC possesses some specific function distinguished from the other members of epidermal growth factor (EGF) family. To clarify this function, the released form of human BTC has been expressed in E.coli, purified, and characterized. The recombinant human BTC was produced as an inclusion body. This material was dissolved in guanidine-HCl under reducing conditions, refolded, and purified through sequential liquid chromatography. Purified BTC was electrophoresed under reducing conditions and a molecular size of 18 kDa was determined, which is the supposed size of a dimer of the peptide. However, chemical analysis failed to show a covalently linked dimer. The molecular mass of BTC analyzed by mass spectrometry revealed it to be 9 kDa, which is consistent with theoretical value for a monomer. Recombinant BTC showed growth promoting activity for mouse fibroblasts and rat aortic smooth muscle cells which was equivalent to EGF On the other hand, BTC was found to exhibit a growth inhibitory effect on the cells overexpressing EGF receptor.

3T3 Cells↗
PubMed1996

[Postoperative olfactory dysfunction in interhemispheric approach for ruptured anterior communicating artery aneurysms].

Between 1969 and 1994 we treated 450 patients with ruptured anterior communicating artery aneurysms, of which 434 cases (96.4%) were operated on via the interhemispheric approach (IH), namely, until 1979 mainly, via bifrontal craniotomy, subfrontal and interhemispheric approach (SIH) and, since 1979, via posterior interhemispheric approach (PIH). Postoperative olfactory dysfunction is one of the main disadvantages of IH. The mechanisms and the incidence of this disadvantage were studied in both approaches. The causes of postoperative anosmia in SIH were as follows: sectioning of olfactory tracts intentionally or not, avulsion of olfactory bulbs and probability of ischemic or minor mechanical insults to olfactory tracts. However, these matters rarely occur in PIH because of little exposure of olfactory nerves. The mechanisms of postoperative anosmia in PIH were considered to be as follows: sinking of frontal lobes due to excessive drainage of cerebrospinal fluid and over-retraction of frontal lobes. The incidence of postoperative anosmia decreased from 27.0% via SIH to 5.5% via PIH.

Aneurysm, Ruptured↗
PubMed1996

Age-related decrease in the inductability of heat shock protein 72 in normal human skin.

In order to know the effect of chronological ageing on the induction of heat shock protein (HSP) in normal human skin, the 72-kDa HSP (HSP72) was examined in organ-cultured samples of normal human skin which were obtained from 30 individuals (age range 17-86 years). The skin explants were first incubated at 37 degrees C for 24 h, and then heat-treated at 45 degrees C for 1 h. After heat treatment, the skin explants were incubated at 37 degrees C for 1 or 3 h. Immunohistological analysis, using a monoclonal antibody specific for the HSP72, revealed that although the time course of the heat-induced HSP72 expression was similar in the young and aged groups, a lower level of induction of HSP72 was observed in the aged group. This result indicates that there is an age-related dysfunction of the heat shock response in normal human skin.

Adolescent↗
PubMed1996

Trichilemmal carcinoma developing in a burn scar: a report of two cases.

Two cases of trichilemmal carcinoma (TLC) developing in burn scars are reported. In Case 1, a 73-year-old man developed a TLC on his left lower leg five years after a burn. In Case 2, a 43-year-old man developed a cauliflower-like mass on his head 42 years after a burn. Histologically, tumor cells showed a lobular proliferation in continuity with the epidermis. Tumor nests were mostly composed of large atypical cells with clear cytoplasms containing PAS-positive, diastase sensitive materials. Some of the nests showed trichilemmal-type keratinization. These cases were treated only with surgical excision, and there has been no evidence since of local recurrence or metastasis.

Adult↗
PubMed1996

[Hemodynamic simulation study of cerebral arteriovenous malformations: changes of wall stress and early detection of NPPB].

Obliteration procedures for large high-flow arteriovenous malformations (AVM) were simulated using a compartmental flow model to investigate the role of altered autoregulatory conditions in the development of hyperperfusion and normal perfusion pressure breakthrough (NPPB). Since the arterioles are primarily responsible for autoregulatory function, the role of these structural changes on the development of hyperperfusion was also studied by evaluating the wall thickness (T), internal radius (Ri) and tangential wall stress (sigma). As the AVM flow was decreased during the obliteration procedures, the perfusion pressure (delta P) of the brain tissue surrounding the AVM increased. When the autoregulatory condition was impaired [AR (-)] and the lower limit of the autoregulatory pressure range (LAR) was shifted from 60 mmHg (LAR60) to 40 mm Hg (LAR40), the flow volume in the surrounding brain (Fb) increased markedly, from 67 ml/100g/min to 92 ml/100g/min, with the progress of the obliteration procedures. In these conditions, T/Ri was supposed to be constant and sigma value increased uniformly. In the presence of the autoregulatory mechanism [AR (+)], T/Ri increased against increasing delta P, which resulted in smaller sigma value than that under AR (-) conditions. When the contracted vascular wall yielded on the process of increasing wall stress, delta P and feeder pressure (Pf) decreased to some degree. Concomitantly increase of the sigma value and marked hyperperfusion developed in the brain. The yield of the contracted vascular wall would result in the decrease of a pressure gradient across the arteriole and the reciprocal increase of pressure load on the walls of the capillary and venula, which might lead to NPPB. Since the decrease of delta P or Pf during the progress of the obliterating procedures is considered specific to the appearance of hyperperfusion or NPPB, monitoring these parameters would be useful for its early detection. If the upper limit of the autoregulatory pressure range was assumed to decrease and become the yield point in the brain surrounding high flow AVMs, hyperfusion or NPPB could be considered to develop in the conditions with the autoregulatory pressure range being narrowed and/or shifted to the lower pressure level. Induced systemic hypotension was found to be effective in reducing the magnitude of Fb, delta P, and Pf when induction was appropriately performed in stepwise fashion. T/Ri and sigma were kept in narrow ranges compared to those before induction of hypotension.

Arterioles↗