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Biomedical subjects

H Takeuchi

Publications and source records attributed to H Takeuchi.

At least 721 records · Page 40Linked to original sources
PubMed1988

Characterization of individual tryptophan side chains in proteins using Raman spectroscopy and hydrogen-deuterium exchange kinetics.

Two Raman bands at 880 and 1360 cm-1 of tryptophan (Trp) side chains have been found useful in structural studies of the side chains in proteins. The frequency of the 880-cm-1 band reflects the strength of H bonding at the N1H site of the indole ring: the lower the frequency is, the stronger the H bonding is. The intensity of the 1360-cm-1 band, on the other hand, is a marker of the hydrophobicity of the environment of the indole ring: particularly strong in hydrophobic environments. It is also demonstrated that a combination of stepwise deuteration of the tryptophan side chains and difference spectrum techniques is useful to observe these marker bands due to each side chain separately. The states of six tryptophans in lysozyme revealed by this Raman spectroscopic method in solution are compared with those by X-ray diffraction in crystal. The Raman data on the outer four Trp's are consistent with the X-ray structure, whereas significant differences between solution and crystal are suggested for the strength of H bonding of the most and second most buried Trp's. Characterization of four Trp's in alpha-lactalbumin shows that the two outer Trp's are moderately H bonded to solvent water and closely surrounded by aliphatic side chains while the inner two are not H bonded nor closely surrounded by aliphatic side chains.

Deuterium↗
PubMed1988

Effects of synthetic biologically active peptides on giant neurones identified in the left buccal ganglion of an African giant snail (Achatina fulica Férussac).

1. The effects of synthetic biologically active peptides, including Met-enkephalin, substance P, oxytocin, Arg-vasopressin, proctolin and FMRFamide, on the following four buccal neurones were examined: d-LBAN (dorsal-left buccal anterior neurone), d-LBMN (dorsal-left buccal medial neurone), d-LBCN (dorsal-left buccal central neurone) and d-LBPN (dorsal-left buccal posterior neurone). These peptides were examined at 10(-4) M. 2. Oxytocin excited d-LBAN and slightly excited d-LBCN, while this inhibited d-LBMN. Arg-vasopressin excited slightly d-LBAN and d-LBCN, but this had some times no effect. FMRFamide inhibited d-LBAN, and slightly inhibited d-LBCN. 3. No direct synaptic connection from the two ventral cerebral giant neurones, v-LCDN and v-RCDN, to the four buccal giant neurones was found, though the two cerebral neurones innervate the cerebro-buccal connectives.

Animals↗
PubMed1988

Further study of effects of synthetic peptides on identifiable giant neurones of an African giant snail (Achatina fulica Férussac).

1. Effects of the following peptides at 10(-4) M on identifiable giant neurones of Achatina fulica Férussac were examined: physalaemin, eledoisin, bradykinin, neurokinin A, neurokinin B, neuromedin B, gastrin releasing peptide decapeptide (neuromedin C), gastrin releasing peptide (14-27), cholecystokinin tetrapeptide, cholecystokinin octapeptide, thyrotropin releasing hormone, Arg-vasotocin, gamma-melanocyte stimulating hormone. 2. The six neurones tested were as follows: PON (periodically oscillating neurone), TAN (tonically autoactive neurone), RAPN (right anterior pallial neurone), d-RPLN (dorsal-right parietal large neurone), VIN (visceral intermittently firing neurone) and d-VLN (dorsal-visceral large neurone). 3. Of the peptides examined, only Arg-vasotocin at 10(-4) M produced the excitatory effects on PON, VIN and d-VLN. Physalaemin showed slight inhibitory effects on TAN; this substance was sometimes almost ineffective on the neurone. 4. The other peptides examined were completely ineffective on all of the neurones tested.

Animals↗
PubMed1988

Eosinophilic sclerosing lipogranuloma of the male genitalia not caused by exogenous lipids.

A type of sclerosing lipogranuloma of the male genitalia that is different from cases caused by injection or application of foreign bodies is reported in 4 patients. The characteristics of the disease are a symmetrical Y-shape of the granuloma, spontaneous regression, severe infiltration of eosinophils in the granuloma, eosinophilia of the peripheral blood and absence of any exogenous lipids by chemical analyses of the granuloma tissue. Ultrastructural study showed intracytoplasmic fat vacuoles of varied size in histiocytes and multinuclear giant cells. This is a new type of sclerosing lipogranuloma of the male genitalia and the pathogenesis of the disease is still unknown.

Adult↗
PubMed1988

4-vinyl and 2,4-divinyl deuteration effects on the low frequency resonance Raman bands of myoglobin: correlation with the structure of vinyl group.

Resonance Raman spectra of myoglobin (Mb) reconstituted with 4-vinyl and 2,4-divinyl deuterated protoheme IX were studied in several oxidation, spin, and ligation states (deoxyMb, MbO2, MbCO, metMbH2O, and metMbCN-) with special attention to the low frequency vibrations. Frequency shifts observed on deuteration enabled us to assign some Raman bands to vibrations specifically involving the 2- or 4-vinyl group. The most significant deuteration effect was found for a band around 410 cm-1 in the ferrous state, which loses intensity on 4-vinyl deuteration and is ascribed to a porphyrin in-plane vibration strongly coupled with the skeletal bend of the vinyl group at position 4. Such strong coupling implies that the vinyl group lies in the same plane as the pyrrole II ring, as in the crystalline state. Thus, frequency shifts on vinyl deuteration may be useful as a probe of the orientation of the vinyl group. Resonance Raman spectra of Mb coordinated with various sizes of isocyanides are interpreted in terms of vinyl orientational changes induced by ligation.

Deuterium↗
PubMed1988

Metronidazole neuropathy: a case report.

A 67-year-old man developed peripheral neuropathy characterized by glove and stocking type sensory disturbances after the ingestion of 101.25 g of metronidazole for hepatic amebiasis. The clinical pictures of metronidazole-induced neuropathy appears to be the same as that of myeloneuropathy. The morphological study of a sural nerve biopsy showed a severe loss of myelinated fibers (2,400 per mm2). The density of unmyelinated fibers was at a lower limit of the normal range (23,530 per mm2). Electronmicroscopy confirmed the axonal degeneration of both the myelinated fibers and unmyelinated fibers.

Aged↗
PubMed1988

Behçet's disease with chylothorax--case report.

Behçet's disease is a systemic disease primarily affecting the eye, genital, and oral mucosa but is known to have various rare complications. A patient with a twenty-year history of Behçet's disease was admitted owing to dyspnea caused by massive chylothorax. Administration of corticosteroid, heparin, and urokinase was ineffective, but the thoracic fluid was well controlled by pleuropexy with Broncasma Berna. Chylothorax complicating Behçet's disease is extremely rare, having been reported in only 2 cases.

Adult↗
PubMed1988

[Marginal periodontitis and the immune system. III. Differences in peripheral blood lymphocyte subsets before and after treatment in adult periodontitis patients].

The lymphocyte subsets in the peripheral blood of 8 individuals, aged 25 to 57 yr, with moderate to advanced adult periodontitis were analyzed before and after treatment by means of flow cytometry, and then compared with the findings in 20 normal adults (aged 30 to 45 yr). The results were as follows: the percentage of OKT-8+ (CD 8) in the patients (20.25 +/- 7.15%) was lower than that in normal individuals (31.50 +/- 6.03%, P less than 0.01) while the OKT-4/OKT-8 ratio (2.34 +/- 1.18) was higher than the corresponding ratio in the controls (1.23 +/- 0.37); however, there was no significant difference in the percentages of OKT-3+ (CD 3), OKT-4+ (CD 4) and Leu-12+ (CD 19) between patients and normal subjects. The percentages of OKT-3+, OKT-4+, OKT-8+, Leu-12+ and OKT-4/OKT-8 after the periodontal therapy did not show a significant difference compared with the data obtained before treatment. These results indicate that the decrease in suppressor/cytotoxic T-cell population may be a kind of pathological disposition of the initiation and/or course of adult periodontitis.

Adult↗
PubMed1988

[Complete remission of stage III penile cancer by multidisciplinary treatment: report of a case].

A case of penile cancer with bilateral metastatic inguinal lymph nodes in a 68-year-old male is reported. We used combination chemotherapy with methotrexate, bleomycin, and cisplatin for 2 courses before ilioinguinal lymphadenectomy. The surgical specimen of ilioinguinal lymph nodes revealed no viable tumors. It is clear that this combination therapy was effective against metastatic penile cancer and the role of preoperative chemotherapy is becoming increasingly important in metastatic penile cancer. This chemotherapy and surgical approach deserves additional trial in patients with metastatic penile cancer.

Aged↗
PubMed1988

[Genital Paget's disease with general metastasis: a case report].

A 74-year-old man with the chief complaint of ulceration of penile shaft and scrotal swelling was referred to our hospital on November 7, 1985. Biopsy specimen of the local lesion histologically revealed invasive adenocarcinoma with Paget's cell. Clinical studies revealed a high serum carcinoembryonic antigen (CEA) level and regional lymph node metastasis was highly suspected. We concluded that the patient was suffering from Stage II genital Paget's disease. Emasculation, bil-inguinal and pelvic lymph node dissection, and free skin mesh grafting were performed on December 24, 1985. Histological findings of the tumor confirmed Paget's disease and bil-inguinal and pelvic lymph node metastases. CEA staining showed CEA positive malignant cells in both the primary lesion and metastatic lymph nodes. After operation, the rapid deterioration of the patient's condition was accompanied by extremely high serum CEA levels, obstructive jaundice, and evidence of metastasis to the liver. He died 24 days after operation and autopsy could not be performed. We recommend aggressive treatment when clinical studies reveal invasion to the epidermis, high serum CEA levels and lymph node metastasis.

Aged↗