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Biomedical subjects

T Katayama

Publications and source records attributed to T Katayama.

At least 487 records · Page 27Linked to original sources
PubMed1985

[A therapeutic experience with alloplastic spermatocele used in obstructive azoospermia].

To perform AIH, an artificial spermatocele was inserted into the epididymis for obstructive azoospermia (probably caused by congenital defect of the spermiduct on one side and by accidental vasosection in hernioplasty on the other). The graft used was a cup-shaped alloplastic spermatocele made of silicon-dacron, developed by Wagenknecht et al. The epididymal duct was incised microscopically. The graft was sutured to the epididymal involucrum, punctured through the scrotal skin by an injection needle and aspirated spermatozoa accumulated in the internal cavity, and subjected to AIH. Postoperatively, acceleration of spermatogenesis was attempted by injecting i.m. HCG 2,000 U-HMG 150 U twice a week, but spermatozoa both qualitatively and quantatively sufficient to perform AIH could not be obtained. Spermatozoa were no longer found after two and a half postoperative months. Despite the present failure, we would like to develop a method of grafting of this kind as more precise therapeutic means through further technical improvements in grafting.

Adult↗
PubMed1985

Experimental morphological studies on the functional role of the pulpal nerves in dentinogenesis.

The role of the pulpal nerves in the dentinogenesis of the rat dentition was studied experimentally by means of a time marker of lead acetate and by electron microscope after the individual dissection of the trigeminal and cervical sympathetic nerves or both. Following trigeminectomy, the longitudinal growth of the denervated incisor decreased. Contrary to this, following cervical sympathectomy, the longitudinal growth of the denervated incisor and molar increased 10-5%, and the collagen fibers increased predominantly in the pulpal tissue. The sympathetic nerves seem to play an important part in controlling the differentiation of the odontoblasts, inhibiting the maturation of the growth center of the apical pulp in the continuously developing teeth.

Animals↗
PubMed1985

Therapeutic experience of advanced urothelial tract tumors.

Twenty-three patients with locally advanced and/or metastatic urothelial tumors were treated by surgery, chemotherapy or radiation. Radical operation with or without radiation resulted in tumor free conditions in 8 patients. Fifteen patients who had a few dimensionally estimable disease parameters, underwent chemotherapy. Objective responses were obtained in 6 of the 15 patients (1 CR and 5 PR). The objective response of low grade or low stage tumors or cases with high Karnofsky performance ratings was moderate. Combination chemotherapy with cisplatin (CDDP), doxorubicin (ADM) and cyclophosphamide or a CDDP-containing combination appeared to be beneficial for patients with advanced urothelial tract tumors with palliative purpose.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1985

[Cis-platinum used for the prevention of the recurrence of adrenal cortical carcinoma: report of a case].

The right suprarenal mass was found in a 21-year-old housewife. Her major clinical features were amenorrhea, polydipsia and buffalo hump obesity. Endocrinological and roentgenological studies suggested the presence of Cushing's syndrome due to adrenocortical carcinoma in addition to ipsilateral renal stone. The huge adrenal tumor and renal calculus were successfully removed. The histological diagnosis was adrenocortical carcinoma. Seventeen days after the operation, cis-platinum was administered to prevent the recurrence of tumor development. No recurrence has been observed for approximately 2 years after the surgery. Long follow-up must be pursued to clarify the real efficacy of cis-platinum treatment.

Adenocarcinoma↗
PubMed1985

[XX-male in a case of male infertility].

A 26-year-old man with the chief complaint of male infertility for 3 years was referred to our clinic. Physical examination of the patient revealed normal male habitus except for a small testis. His semen analysis showed no sperm. Levels of plasma LH and FSH were high compared with normal ones but that of plasma testosterone was within the normal range. Histological examination of his testis showed no spermatogenesis. Chromosome analysis with peripheral blood revealed 46, XX. H-Y antigen could be detected by in vitro cytotoxicity tests. By the above findings, the diagnosis of XX-male was made. Literature dealing with this disease is scanty. Only 18 cases of XX-male including our case were collected in Japan. The etiology and clinical features of this disease are discussed in the present report.

Adult↗
PubMed1985

[Therapeutic experiences of seishinrenshiin in patients with equivocal complaints of the lower urinary tract].

To study its clinical effect, Tsumura Seishinrenshiin, was administered to male patients of chronic prostatitis and urethritis with various equivocal complaints of the lower urinary tract and female patients complaining of cystitoid symptoms inspite of normal urine. These subjects were 35 males, 20 to 69 years and 7 females 22 to 78 years. For the patients who had constitutionally infirm stomach and intestines the rate of effectiveness reached 41%, which was rather satisfactory. For the other patients, however, it was only 28%. Besides no correlation was observed between the age of patient and the effectiveness. A combined administration of antibiotics and antibacterial agents led to no increase in the effectiveness. All of the side effects were rather slight, which permitted its continuous administration over a period of more than 4 weeks. From the above findings Seishinrenshiin was expected to be both effective for the patients who have constitutionally infirm stomach and intestines and can be used safely.

Adult↗
PubMed1985

Structural and functional adaptation of the pulpal nerve fibers in the rat incisor.

Special fine structure of the pulpal nerve fibers adapted to the continuously growing incisor was studied on 20 rats (25-d-old-males) electron microscopically and was compared with that of the molars of limited growth. The incisal pulp was innervated by 2 kinds of the nerve fibers derived from the cervical sympathetic and the trigeminal ganglia: polyaxonal unmyelinated and monoaxonal myelinated. In the apical pulp, however, the pulpal nerve fibers were unmyelinated, showing 3 different profiles in the fine structure: 1. polyaxonal, 2. polyaxonal with dial plate-like profile and 3. monoaxonal. The monoaxonal unmyelinated fiber reflected the transverse profile of the unmyelinated part of the myelinated axon derived from the trigeminal ganglion. It can be concluded that the pulpal nerve fibers derived from the trigeminal ganglion maintain the immatured nature in the apical proliferating pulp to adapt to the continuous growth of the incisor.

Animals↗
PubMed1984

Purification and characterization of an enkephalin-degrading aminopeptidase from guinea pig serum.

An enkephalin-degrading aminopeptidase using Leu-enkephalin as a substrate was purified about 4100-fold from guinea pig serum. The purified preparation was apparently homogenous, showing one band on polyacrylamide gel electrophoresis. The molecular weight of the enzyme was approx. 92 000. The aminopeptidase had a pH optimum of 7.0 with Km values of 0.12 mM and 0.18 mM for Leu- and Met-enkephalin, respectively. The enzyme hydrolyzed neutral, basic and aromatic amino acid beta-naphthylamides, but did not the acidic one. The enzyme was inhibited strongly by metal-chelating agents, bestatin and amastatin and weakly by puromycin. Among several biologically active peptides, angiotensin III and substance P strongly inhibited the enzyme.

Animals↗
PubMed1984

Detection of myocardial infarction extension or reattack by serum myoglobin radioimmunoassay.

We evaluated serum myoglobin levels in patients with acute myocardial infarction and investigated their diagnostic significance on episodic reattack on the course of acute infarction. Myoglobin was measured by radioimmunoassay, and the upper limit of normal was 50 ng/ml. Raised myoglobin levels were present in 52 of 53 patients (98%) with documented acute myocardial infarction admitted within 12 hr and in 16 of 20 patients (80%) admitted between 12 and 24 hr after the onset. Maximal values occurred 11.1 +/- 5.0 (mean +/- SD) hr and returned to the normal ranges 1.6 +/- 1.1 days after the onset. Because of its early normalization and high sensitivity to new necrosis, myoglobin might be a useful biochemical marker for diagnosis of infarct extension or reattack. Forty-seven episodic reelevations were classified into three groups (definite, probable and possible) according to the rating system indicating reattack of myocardial infarction. The incidence of definite and probable reattack or extension was 21%, and possible 19%. Reelevation of serum myoglobin occurred on an average of 5.0 days after the initial attack, within the first 3 days in 53% and on the second day in 31%. These results might suggest that an unexpectedly large cohort of myocardial infarction shows reattack in its early days of initial suffering.

Adult↗
PubMed1984

Purification and characterization of two distinct dipeptidyl aminopeptidases in soluble fraction from monkey brain and their action on enkephalins.

Two distinct dipeptidyl aminopeptidases, which were designated DPP-A and DPP-B, were purified from soluble fraction of monkey brain using Leu-enkephalin as the substrate. The enzymes were purified 187 and 136 fold, respectively. Both enzymes showed the optimum pH in neutral range. Their molecular weights were almost equal and were estimated to be about 100,000. Their Km values with Leu-enkephalin as the substrate were 5.6 X 10(-5) and 1.1 X 10(-5) M, respectively. Among synthesized substrates, the highest affinity of the enzymes was toward arginyl-arginine beta-naphthylamide with the Km values of 6.25 X 10(-5) and 6.41 X 10(-5) M, respectively. Both enzyme activities were inhibited by the metal-chelators DFP and PCMB. Two hundred fifty microM arphamenine A inhibited DPP-A and -B with inhibition of 36.6% and 44.1%, respectively. Beta-endorphin, ACTH, and glucagon inhibited only DPP-B, while beta-lipotropin and angiotensin II inhibited both DPP-A and -B when Leu-enkephalin was used as the substrate.

Animals↗
PubMed1984

Inhibition of a membrane-bound enkephalin-degrading aminopeptidase by bestatin analogs.

A variety of bestatin analogs were examined as potent inhibitors of a membrane-bound enkephalin-degrading aminopeptidase that was purified from monkey brain. Bestatinyl amino acid derivatives showed strong inhibition of this enzyme. The most effective was bestatin-L-Arg X AcOH, with a Ki value of 0.21 X 10(-8) M with Leu-enkephalin as substrate. It exhibited competitive kinetics and was about 100-fold more potent than bestatin. This compound seems to be useful for pharmacological and other studies.

Aminopeptidases↗
PubMed1984

[A case of XYY syndrome with male infertility and retentio testis].

A case of the XYY syndrome is reported. A 29-year-old man visited our hospital because of infertility and right undescended testicle. He was tall (181 cm) and his intelligence level was below average but his character was not violent. His right testis was touched in his right inguinal region and it was atrophic. Analysis of the semen showed no sperm. The biopsied specimen of his left descended testis as well as right undescended testicle showed spermatogenic arrest. Consequently we speculated that the spermatogenesis was injured by the surplus Y chromosome. On endocrinologic examination, plasma LH and FSH were high and testosterone revealed to be low. These data were slightly abnormal, but similar to those of most previous investigators.

Adult↗