Biomedical subjects

M Yasuda

Publications and source records attributed to M Yasuda.

At least 271 records · Page 15Linked to original sources

PubMed1995

Interaction of 6-p-toluidinylnaphthalene-2-sulfonate with beta-cyclodextrin.

The interaction of 6-p-toluidinylnaphthalene-2-sulfonate (TNS) with beta-cyclodextrin was investigated in 0.1 M phosphate buffer at pH 7.4 by fluorescence spectroscopy. Using the fluorescence enhancement of TNS in the presence of beta-cyclodextrin, the thermodynamic parameters for the formation of two kinds of the inclusion complex (molar ratio of beta-cyclodextrin to TNS = 1:1 and 2:1) were determined as follows: delta G degree 1 (1:1 complex) = -20.0 kJ mol-1 at 25 degrees C, delta H degree 1 = -19.6 kJ mol-1, delta S degree 1 = -1.7 J mol-1 K-1, delta G degree 2 (2:1 complex) at 25 degrees C = -6.14 kJ mol-1, delta H degree 2 = -2.80 kJ mol-1, delta S degree 2 = 16.7 J mol-1 K-1. From the thermodynamic parameters, the main driving force for the 1:1 inclusion complex formation was considered to be the van der Waals-London dispersion force, while the contribution of the hydrophobic interaction was small. Also, the hydrogen bonding was suggested to contribute to the inclusion complex formation. The main driving force for the 2:1 inclusion complex formation was the hydrophobic interaction. Also, from the measurements of proton nuclear magnetic resonance spectra and studies with Corey-Pauling-Koltun atomic models, the probable structure was determined and discussed in connection with the thermodynamic parameters.

Cyclodextrins↗

PubMed1995

Esophageal squamous cell carcinoma occurring in the surface epithelium over a benign tumor.

The coexistence of a benign tumor and carcinoma in the same esophagus is uncommon, while the occurrence of carcinoma in the surface epithelium over a benign tumor is considered to be extremely rare. Among 587 patients with surgically resected esophageal cancer, the cases with carcinoma located over a benign tumor of the esophagus were histopathologically investigated and the carcinogenesis of such cases was discussed. Only three cases were found to have esophageal squamous cell carcinoma located over benign tumors (two were leiomyomas and one was a lipoma). All three benign tumors protruded to the esophageal surface, and the carcinoma was located just over such tumors without coexisting epithelial dysplasia. Moreover, the epithelium, except for portions around these tumors, was intact in all three cases. From these findings it was suggested that chronic stimulation of the epithelium covering the benign tumors might have induced the carcinoma.

Aged↗

PubMed1995

Prospective randomized study of hyperthermia combined with chemoradiotherapy for esophageal carcinoma.

From January 1988 to June 1992, 66 patients with resectable squamous cell carcinoma of the thoracic esophagus underwent preoperative adjuvant therapy. These patients were prospectively divided into two treatment groups; 32 were treated with radiofrequency wave local hyperthermia combined with chemoradiotherapy (hyperthermochemoradiotherapy; HCR), while the remaining 34 patients were treated with chemoradiotherapy alone (CR). There were no procedural complications in either group and the postoperative mortality was zero. In the HCR group, no viable cancer cells were found within the entire 5 mm-width slices of the resected specimen in eight patients (25%), while only two (5.9%) in the CR group (P < 0.05) demonstrate no viable cancer cells. The cumulative 3-year survival rate was 50.4% in the HCR group and 24.2% in the CR group. The present prospective trial demonstrated that the addition of hyperthermia to chemoradiotherapy resulted in a better local control and an improved long-term survival when treating patients with advanced esophageal carcinoma.

Adult↗

PubMed1995

Rheumatoid arthritis in the northeastern area of the People's Republic of China and western Japan.

The clinical features of 134 consecutive hospitalized patients with rheumatoid arthritis in the northeastern area of the People's Republic of China and 251 consecutive hospitalized patients from western Japan were compared. A total of 91.8% of the Chinese patients were of Han nationality, while all of the patients from Japan were Japanese. The patients in the People's Republic of China showed more inflammatory articular disease and more frequent subcutaneous nodules than did the Japanese patients in the presence of a less elevated ESR value and less radiographic joint destruction. The clinical features of the patients of Han nationality and the Japanese did not change even after adjusting the patients' age and disease duration. The reasons for the contradictory features in the Chinese patients still remain to be clarified. This study is hopefully a first step in promoting more precise studies on rheumatoid arthritis in the People's Republic of China.

Adult↗

PubMed1995

Conserved delta-activity in reverse enantiomeric opioid peptide.

A reverse enantiomeric peptide has a reversed amino acid sequence with enantiomeric amino acid residues compared with its parent peptide. In most cases the random change of amino acid sequence or chirality might be expected to bring about significant changes in peptide activity. However, the reverse enantiomeric peptides of Leu-enkephalin and Tyr-D-Ala-Gly-Phe-D-Leu (DADLE) have shown affinity for the opioid delta-receptor, but not for mu- or kappa-receptors. This suggests that delta-opioid receptor recognition occurs primarily through interaction with the peptide side chains, since the native opioid peptide and its reverse enantiomer are able to have similar side-chain conformation.

Amino Acid Sequence↗

PubMed1995

Prospective studies of the association between anticardiolipin antibody and outcome of pregnancy.

OBJECTIVE: To investigate the association of anticardiolipin antibody with the genesis of spontaneous abortion, fetal growth restriction (FGR), and preeclampsia. METHODS: Eight hundred sixty pregnant women constituted the study population. Anticardiolipin antibody was screened by enzyme-linked immunosorbent assay during the first trimester of pregnancy. The outcome of pregnancy in these women was analyzed prospectively, and the rate of occurrence of spontaneous abortion, preeclampsia, and FGR was compared in the anticardiolipin antibody-positive and -negative groups. RESULTS: Anticardiolipin antibody was positive in 60 of the 860 women (7.0%) and negative in 800 (93.0%). The rate of spontaneous abortions in the anticardiolipin antibody-positive group, 25.0%, was significantly higher than that in the anticardiolipin antibody-negative group, at 9.8% (P < .001; relative risk [RR] 2.56, 95% confidence interval (CI) 1.37-4.81). The rates of preeclampsia (11.7%) and FGR (11.7%) in the anticardiolipin antibody-positive group were also significantly higher than those in the -negative group (1.9 and 1.9%, respectively; for preeclampsia, P < .001; RR 6.22, 95% CI 2.43-16.0 and for FGR, P < .001; RR 6.22, 95% CI 2.43-16.0). CONCLUSIONS: Anticardiolipin antibody is associated with adverse outcomes of pregnancy such as spontaneous abortion, preeclampsia, and FGR.

Abortion, Spontaneous↗

PubMed1995

Low cerebrospinal fluid concentrations of peptide histidine valine and somatostatin-28 in Alzheimer's disease: altered processing of prepro-vasoactive intestinal peptide and prepro-somatostatin.

Recent studies have indicated that deposition of beta amyloid peptide in the brains of patients with senile dementia of the Alzheimer type (SDAT) is a consequence of abnormal processing of the beta amyloid protein precursor. In addition, reduced concentrations of various peptides have been measured in post-mortem brain tissue and cerebrospinal fluid (CSF) of patients with SDAT. We determined concentrations of the peptides derived from prepro-vasoactive intestinal peptide (VIP)--peptide histidine methionine-27 (PHM-27), peptide histidine valine (PHV) and VIP--and peptides derived from prepro-somatostatin (prepro-SS), SS-14 and SS-28, in CSF of patients with SDAT by radioimmunoassay combined with high performance liquid chromatography. We found significantly reduced levels of total PHM-immunoreactivity (IR) and PHV, and unaltered levels of PHM-27 and VIP in SDAT, compared with those in controls. Total SS-IR and SS-28 concentrations were significantly reduced in SDAT, while SS-14 levels did not differ from those of controls. These results suggest that an altered processing of the prepro-peptides of VIP and SS may occur in SDAT and that these alterations might have a significant role in the pathogenesis of SDAT.

Aged↗

PubMed1995

Complete primary structure of chicken cardiac C-protein (MyBP-C) and its expression in developing striated muscles.

C-protein (MyBP-C) is a myosin binding protein of about 140 kDa which is known to modulate myosin assembly in striated muscles. A cardiac-type isoform of C-protein appears not only in cardiac muscle but also in skeletal muscle before skeletal muscle-type isoforms become detectable during myogenesis, suggesting that the cardiac isoform is involved in the early phase of myofibrillogenesis (Bähler et al., 1985; Kawashima et al., 1986). In this study, in order to understand the structure and functional domains of the cardiac-type C-protein, we cloned and sequenced full-length cDNAs encoding chicken cardiac C-protein from lambda gt11 cDNA libraries which were prepared with poly (A)+ RNA from embryonic chicken cardiac muscle as well as embryonic chicken skeletal muscle by using antibodies specific for cardiac C-protein. Two cDNA variants, probably generated by alternative RNA splicing and encoding different C-protein isoforms, were detected. As judged by the cDNA sequences determined, overall homology of the peptide sequence between cardiac and skeletal muscle C-proteins (Einheber et al., 1990; Fürst et al., 1992, Weber et al., 1994) was about 50-55%. Like other myosin binding proteins, skeletal C-proteins, 86 kDa protein and M-protein, cardiac C-protein contains several copies of fibronectin type III motifs and immunoglobulin C2 motifs in the molecule, but their number and arrangements differed somewhat from those in the other proteins. Northern blot analysis with the cloned cDNA as a probe demonstrated that mRNA of 5.0 kb is transcribed in both cardiac and embryonic skeletal muscle, and that it is specifically expressed in cardiac muscle among adult tissues.

Amino Acid Sequence↗

PubMed1995

Correction of dorsi-flexed intercalated segment instability after restoration of scaphoid height in a cadaver model of scaphoid non-union.

Models of scaphoid non-union with static dorsi-flexed intercalated segment instability were produced in five frozen arms from cadavers or subjects following accidents by repetitive mechanical loading of the wrist joints longitudinally after a bone defect has been made at the mid-portion of the scaphoid. We designed four models of reduction: anatomical reduction; reduction with a shortened scaphoid; anatomical reduction but with the radio-lunate ligament sectioned, and a shortened scaphoid with the radio-lunate ligament sectioned. Results suggested that anatomical reduction with rigid fixation with a Herbert screw was most effective for correction of malalignment with DISI. Preservation of the radio-lunate ligament during the palmar approach to the scaphoid seemed to be important to prevent ligamentous carpal instability.

Bone Screws↗

PubMed1995

The prognostic significance of the cytophotometric DNA content and its relationship with the argyrophilic nucleolar organizer regions (AgNOR) and proliferating cell nuclear antigen (PCNA) in oesophageal cancer.

We examined the DNA pattern, AgNOR number and PCNA-positive ratio (PCNA ratio) from biopsy specimens of oesophageal carcinoma, and attempted to identify any prognostic factors for oesophageal carcinoma. DNA analysis: the cell nuclear DNA content was measured and the distribution pattern of the DNA content was grouped into four types according to the ploidy pattern (n = 182). The survival rate of patients with high-ploidy tumours (type III and IV) was shorter than that for low-ploidy tumours (type II), (P < 0.05). AgNOR number (n = 99) and PCNA ratio (n = 41): the AgNOR number and PCNA ratio were measured from 100 cancer cells in each specimen. Both the high-AgNOR-number patients (> or = 5) and the high-PCNA-ratio patients (> or = 35) demonstrated poorer prognoses than the low-rate patients (P < 0.05). These results suggest that the DNA pattern, AgNOR number and PCNA ratio may thus reflect the proliferative activity of tumours and therefore also offer the possibility of interdependence among these three factors.

Aged↗

PubMed1995

The long-term results of pre-operative hyperthermo-chemo-radiotherapy for oesophageal carcinoma--a comparison with preoperative radiation therapy alone.

The long-term results of patients with oesophageal carcinoma treated with pre-operative hyperthermo-chemo-radiotherapy (HCR) and pre-operative radiation therapy alone were compared. Twenty-six patients treated with pre-operative hyperthermo-chemo-radiotherapy (HCR Group) and 25 treated with radiation therapy alone (R Group), which demonstrated histopathologically marked effective results (Grade 3), were entered into the study. The 3-year survival rates after oesophagectomy in the HCR Group and the R Group were 67.4% and 41.8%, respectively, while the 5-year survival rates were 50.5% and 34.9%, respectively. Thus post-operative prognosis in the HCR Group was significantly more favourable than that in the R Group (P < 0.05). The local recurrence and distant metastasis rate in the HCR Group was significantly less than in the R Group (P < 0.01). This significant difference in prognosis was thought to be due to the reinforced effects of local regulation by hyperthermia and the systemic control of micrometastasis by chemotherapy in addition to radiation. Our data suggest that for carcinoma of oesophagus, pre-operative hyperthermo-chemo-radiotherapy contributes to prolonged post-operative survival while reducing both local recurrence and micrometastasis.

Antineoplastic Combined Chemotherapy Protocols↗

PubMed1995

Histological suggestions of 'paratransformation' in oesophageal squamous cell carcinoma.

We have postulated that oesophageal squamous cell carcinoma arises from multifocal areas and not from one cell, and we present the circumstantial evidence for field carcinogenesis in oesophageal cancer. Among 290 cases examined with oesophageal squamous cell carcinoma, lymphatic permeation or intramural metastasis was evident in 110 cases. Of these carcinomatous transformation of the epithelium adjacent to either lymphatic vessel permeation or intramural metastasis of the squamous cell carcinoma was recognized in six cases. It is considered that the cancer tissue either in the lymphatic vessel or intramural metastasis promotes a malignant transformation of the squamous epithelium over these foci. 'Paratransformation' is therefore thought to be one of the potential models of origin for oesophageal squamous cell carcinoma.

Aged↗

PubMed1995

Simultaneous carboplatin and radiotherapy for all stages of head and neck squamous cell carcinoma.

The study investigated the toxicity and efficiency of the concomitant administration of radiotherapy and carboplatin to patients with head and neck carcinomas. Sixty-three patients with head and neck squamous cell carcinomas, other than nasopharyngeal cancer and Stage I (UICC) laryngeal cancers, were treated by external radiotherapy and four courses of carboplatin at a dose of 100 mg/m2 per week. In two patients, only three courses were possible due to renal toxicity. In the other 61 patients, toxicities were self-limiting and no patient required interruption of carboplatin administration. No patient required discontinuation of radiotherapy because of acute toxicity. Of 61 evaluable patients, a complete response (CR) was obtained in 11.5% and a partial response (PR) in 60.7% at 40 Gy. In 41 patients treated to 65 Gy (including two patients with maxillary sinus carcinoma, who were treated by debulking surgery), CR was obtained in 76.9% and CR+PR was 100% at the end of treatment. The actuarial survival rate of the 63 patients at 2 years was 69.2%, with a median follow-up period of 24.4 months. One of 12 patients who received salvage surgery after radical radiotherapy has died due to poor wound healing after the surgery. The schedule was safe, providing a weekly check of serum samples was possible. It is likely that the rate of local control and vocal cord preservation in laryngeal tumours might improve if concurrent carboplatin is used. Careful follow-up is required to determine the long-term effect of concomitant carboplatin administration.

Adult↗

PubMed1995

Expression and function of fibronectin binding integrins on rat mast cells.

Adhesion molecules of the integrin family are implicated not only in leukocyte migration but also in leukocyte activation. Here we characterize the expression and function of fibronectin receptor integrins on rat mast cells. A rat basophilic leukemia cell line (RBL-2H3) and phorbol ester-stimulated rat peritoneal mast cells adhered to fibronectin (FN), vitronectin and fibrinogen. These mast cells expressed fibronectin receptor integrins, including very late antigen (VLA)-4, VLA-5 and vitronectin receptor (VNR), as estimated by immunofluorescent staining and inhibition of FN adherence by newly established mAbs reactive with the rat alpha 4 (MR alpha 4-1), alpha 5 (HM alpha 5-1) or beta 3 (HM beta 3-1) chains of the integrin molecules. The beta-hexosaminidase release, a marker for mast cell degranulation, triggered by high affinity IgE receptor (Fc epsilon RI)-mediated stimulation, was enhanced by adhesion of RBL-2H3 cells to either immobilized FN, MR alpha 4-1, HM alpha 5-1 or HM beta 3-1. This FN enhancement of beta-hexosaminidase release was inhibited by soluble MR alpha 4-1, HM alpha 5-1 and HM beta 3-1 as well as by GRGDSP and DELPQLVTLPHPNHLGPEILDVPST peptides which abrogate VLA-5/VNR and VLA-4 binding to FN respectively. In vivo, passive cutaneous anaphylaxis induced by IgE anti-DNP and DNP-BSA was inhibited by concurrent s.c. injection of MR alpha 4-1, HM alpha 5-1 and HM beta 3-1. These results demonstrate that FN receptor integrins expressed on rat mast cells play an important role in regulating mast cell activation both in vitro and in vivo.

Amino Acid Sequence↗

PubMed1995

Effects of progesterone on the metabolism of cancellous bone in young oophorectomized rats.

The effects of progesterone on cancellous bone in young rats were evaluated. Fifty female rats aged 90 days were divided into 5 groups: (1) Sham-operated controls (SHAM); (2) oophorectomized (OVX) rats; (3) OVX rats treated with estrogen (OVX+E); 4) OVX rats treated with progesterone (OVX+P); and (5) OVX rats treated with estrogen and progesterone (OVX+EP). After surgery, some animals were treated subcutaneously (s.c.) with 0.5 mg of estradiol dipropionate depot, with 5 mg of hydroxyprogesterone capronate depot, or with both hormones, at intervals of 7 days. After 180 days, the bone mineral density (BMD) and bone histomorphometry of their lumbar vertebrae and serological parameters were measured. In the OVX+P group, the BMD and the bone volume as shown by bone histomorphometry were slightly higher than in the OVX group, but not significantly. These parameters in the OVX+E and OVX+EP groups were significantly higher than in the OVX group. The OVX+P group showed a significant increase in the labeled surface and a decrease of the osteoclast number, compared to the OVX group. The OVX+P group showed increases of serum alkarine phosphatase and osteocalcin. From these results, it can be concluded that progesterone treatment might intensify bone formation and suppress bone resorption on cancellous bone in oophorectomized rats, although progesterone alone does not have a positive effect on BMD and bone volume.

Animals↗

PubMed1995

DNA gyrase mutations in quinolone-resistant clinical isolates of Neisseria gonorrhoeae.

Eight quinolone-resistant clinical isolates of Neisseria gonorrhoeae were shown to carry mutations in their GyrA proteins. Six isolates had a single amino acid change of serine to phenylalanine at the position corresponding to Ser-83 in Escherichia coli. In addition to the change of serine to phenylalanine, two isolates had another change of aspartic acid to asparagine at the position corresponding to Asp-87 in E. coli.

Amino Acid Sequence↗

PubMed1995

Characterization of the endosymbiont of a deep-sea bivalve, Calyptogena soyoae.

We have purified DNA from gill tissue of a marine bivalve, Calyptogena soyoae, collected from the deep-sea cold seep communities in Sagami Bay, Japan. An rRNA gene was amplified, cloned, and sequenced. In situ hybridization revealed that the sequence is that of a bacterial endosymbiont within the gill of C. soyoae.

Animals↗

PubMed1995

Morphological variation of new Thermoplasma acidophilum isolates from Japanese hot springs.

We isolated 12 strains of Thermoplasma acidophilum from hot springs in Hakone, Japan. T. acidophilum strains showed morphological variation in the crystal-like structure in the cell and the fibrous structure on the cell surface. Two strains tested were sensitive to novobiocin. However, a novobiocin-resistant mutant was obtained by spontaneous mutation.

Base Composition↗