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Biomedical subjects

T Katayama

Publications and source records attributed to T Katayama.

At least 19 recordsLinked to original sources
PubMed1992

Interleukin-4 enhances in vitro mineralization in human osteoblast-like cells.

The effect of human interleukin-4 (hIL-4) on mineralization in human osteoblast-like cells was investigated. Confluent cells were incubated with hIL-4 for 16 or 30 days in the presence or absence, respectively, of alpha-glycerophosphate (alpha-GP), which accelerates the mineralization process. hIL-4 (0.3 ng/ml) induced mineralization with 1.9-, 26- and 37-fold increases of hydroxyproline, calcium, and osteocalcin content, respectively, in the presence of alpha-GP. Mineralization was not induced with other cytokines, hIL-1, hIL-2, hIL-6, or mIL-4. hIL-4 also induced mineralization in the absence of alpha-GP in a manner different from that of 1 alpha, 25(OH)2 vitaminD3 (1,25(OH)2VD3). These findings suggest that IL-4 may play an important role in bone formation.

Alkaline Phosphatase↗
PubMed1992

A new bioabsorbable material for rat vascular cuff anatomosis: establishment for the long-term orthotopic liver transplantation model.

Rat vascular anastomosis was performed using a newly synthesized bioabsorbable material (LA-GA copolymer) cuffs and the ordinary polyethylene cuffs. The LA-GA copolymer cuff which anastomosed the portal vein and the inferior vena cava were patent and developed no collateral veins even after 6 months, keeping the transplanted liver normal. By contrast, the polyethylene cuff anastomosed portal vein was completely occluded and the collateral veins were highly developed, with the transplanted liver showing the fatty degeneration of hepatocytes and numerous regenerative nodules. It is concluded that the LA-GA copolymer cuff is a suitable material for the short and long term study of rat orthotopic liver transplantation.

Absorption↗
PubMed1992

Improved serodiagnosis of non-A, non-B hepatitis by an assay detecting antibody to hepatitis C virus core antigen.

We examined sequential serum samples from 12 patients with well-characterized posttransfusion non-A, non-B hepatitis who had an acute, resolving self-limited type of clinical course for the presence of antibody to the hepatitis C virus nucleocapsid (core) protein (p22) expressed by a recombinant baculovirus. These sera were simultaneously examined for antibody to the hepatitis C virus nonstructural protein (C100-3) that is presently used for blood screening worldwide. In three patients, both anti-p22 and anti-C100-3 antibodies were detected, but anti-p22 was detected much earlier. In four patients, only anti-p22 was detected. Two other patients were considered to be hepatitis C virus carriers who had been already infected with hepatitis C virus. In one patient, only anti-C100-3 was detected, and it was transient. In two patients, neither antibody was detected. Anti-p22 was detected in at least one of eight samples of transfused blood. Of the nine samples of donated blood that were positive for anti-p22, only four were positive for anti-C100-3. This new assay detecting the antibody to the p22 protein is thus useful for the serodiagnosis of non-A, non-B hepatitis in the acute phase and for blood screening.

Antigens, Viral↗
PubMed1992

Electrophysiologic findings in optic nerve dysfunction associated with multiple evanescent white-dot syndrome.

Electrophysiologic findings in a case of multiple evanescent white-dot syndrome were studied. A 37-year-old woman presented with multiple white dots, granularity of the macula, and optic disc swelling in her left fundus. The electroretinogram and electro-oculogram revealed abnormal findings indicative of changes in the retinal pigment epithelium and photoreceptors. In addition, relative afferent pupillary defect, enlargement of the blind spot, a decrease in the critical fusion frequency, staining of the optic disc on fluorescein angiography and prolonged latency of the P100 component with decreased amplitude in pattern-reversal visual evoked cortical potential strongly suggested dysfunction of the optic nerve in this patient.

Adult↗
PubMed1992

Recurrence of superficial bladder tumours after transurethral resection.

From 1979 to January 1990, 48 patients with newly diagnosed superficial bladder tumours were treated by transurethral resection (TUR) at Toyama Medical and Pharmaceutical University Hospital. The relationship between tumour recurrence and the stage, grade, number, or size of the tumours was investigated. The 1-, 2-, 3-, 4- and 5-year non-recurrence rates were 72%, 63%, 47%, 40%, and 40%, respectively. Non-recurrence rate for pTa tumours was significantly higher than that for pT1 tumours (p < 0.05). There was no relationship between tumour grade and recurrence. The rate of recurrence of multiple tumours was higher than that of single ones. There was no difference in non-recurrence rate between tumours smaller than 1 cm and those of 1 cm or larger. Non-recurrence rate in the instillation therapy group was significantly higher than in the non-instillation group (p < 0.05). It was concluded that patients with multiple or high-stage tumours have the risk of a high rate of recurrence and that intravesical chemotherapy is effective in preventing local recurrence in some patients.

Administration, Intravesical↗
PubMed1992

The role of enhanced mitochondrial phosphorylation in rat liver transplantation.

The effects of organ preservation on mitochondrial oxidative phosphorylation activity, adenylate hepatic energy charge, cytochrome content, and redox state of NAD+/NADH couple in rat liver transplantation were compared between a nonpreservation group and a preservation group with grafts preserved for 12 hr in Euro-Collin's solution. At 3 hr after transplantation, the energy charge in the preservation group decreased to 0.60 +/- 0.02 from the control value of 0.86 +/- 0.01, accompanied by a reduction of intramitochondrial redox state of NAD+/NADH couple. In contrast, in the nonpreservation group, the decrease in energy charge was minimally decreased to 0.79 +/- 0.04 due to the compensatory enhancement of mitochondrial oxidative phosphorylation activity. These results suggest that an enhanced mitochondrial ATP synthesis and a reduced intramitochondrial redox state are important factors affecting survival following rat liver transplantation.

Adenine Nucleotides↗
PubMed1992

Effect of birth season on case fatality rate of pulmonary tuberculosis: coincidence or causality?

The effects of birth season on the case fatality rate (CFR) of pulmonary tuberculosis were examined in case records of 9206 patients discharged during 1937-1965 from a national hospital for tuberculosis in Tokyo. The CFR was over 60% until 1945, then it decreased down to less than 9% after 1950. Male cases had little variation in their CFR by their birth season, while female cases had a significant variation and showed a significantly higher CFR than the male cases when they were born in January-June. The results suggest that the birth season had a significant influence on the prognosis of pulmonary tuberculosis.

Delivery, Obstetric↗
PubMed1992

Hepatoblastoma in a 2-year-old girl with trisomy 18.

A very rare case of mosaic type trisomy 18 associated with hepatoblastoma is described. The patient underwent an extended right hepatic lobectomy at 2 years of age, and the resected tumor was diagnosed as a fetal type dominant hepatoblastoma. The results of chromosome analysis demonstrated that in the peripheral blood and skin, the trisomy 18 cells were 80% and 67%, respectively. On the other hand, although virtually 100% of the cells in the normal liver tissue were 46, XX, about one third of the cells were trisomy 18 in the tumor tissue. At 2 years and 9 months after the operation, the patient was generally healthy and had no evidence of recurrence.

Carcinoma, Hepatocellular↗
PubMed1992

Control of trigeminal motoneurons from the cerebellar interpositus nucleus of the guinea pig.

1. Effects of stimulation of the cerebellar interpositus nucleus (IPN) on jaw reflexes and trigeminal motoneurons were studied along with the route responsible for the effects in ketamine-anesthetized guinea pigs. 2. Stimulation in the IPN evoked a bilateral, ipsilaterally dominant, short-latency reciprocal effect on jaw reflexes: a depression of the jaw-closing masseteric reflex and a facilitation of the jaw-opening digastric reflex. This reciprocal phase was followed by a non-reciprocal facilitatory phase. 3. Stimulation in the IPN evoked a short-latency, strychnine-sensitive inhibitory postsynaptic potential (IPSP) followed by a rebound depolarizing potential in the jaw-closing masseter motoneurons (MAMNs) and an excitatory postsynaptic potential (EPSP) in the jaw-opening anterior digastric motoneurons (ADMNs). The time course of the intracellular response of MAMNs to the IPN stimulation was similar to that of the IPN-induced effects on the jaw-closing reflex. In contrast, the duration of the IPN-induced EPSP in ADMNs was shorter than the IPN-induced facilitation of the jaw-opening reflex. 4. After the IPN neurons were lost by injection of kainic acid into the nucleus, the reciprocal effect of the IPN stimulation on the jaw reflexes could not be seen, even though the projection fibers from the trigeminal sensory nucleus to the IPN remained essentially intact. 5. Stimulation in the superior cerebellar peduncle (SP) induced the same reciprocal effect on the jaw reflexes as the IPN stimulation. A lesion of the SP virtually abolished the reciprocal effect on the jaw reflexes of stimulation in the IPN ipsilateral with reference to the SP lesion. 6. Transection of the brain stem at the level immediately caudal to the red nucleus did not affect the reciprocal effect of the IPN stimulation on the jaw reflexes. 7. We conclude that the IPN output bilaterally induces an inhibition of jaw-closing MAMNs and an excitation of jaw-opening ADMNs, oligosynaptically by way of a direct cerebelloreticular projection system via the SP.

Animals↗
PubMed1992

Epidermal growth factor in urine from the patients with urothelial tumors.

Epidermal growth factor (EGF) concentration in urine was measured with a radioimmunoassay in 40 untreated patients with urothelial tumors and a comparable control group of 25 normals. The concentration of EGF in urine from the patients with bladder, renal pelvic or ureter tumors was lower than normal (p less than 0.05). Patients with T4 tumors had lower concentrations of EGF compared with those of other stages. EGF concentrations after transurethral resection of bladder tumors were significantly elevated compared with the values before operation. These findings suggest that urothelial tumors are related to a low concentration of EGF and that a decrease of EGF is associated with invasion of tumors.

Carcinoma, Transitional Cell↗
PubMed1992

Evaluation of seminal vesicle characteristics by ultrasonography before and after ejaculation.

Twenty males underwent transrectal ultrasonography before and after ejaculation to examine possible alterations that could influence interpretation of seminal vesicle ultrasonography. The preejaculation length of 35 mm was significantly (p < 0.05) decreased to 30 mm after ejaculation. The mean width of the seminal vesicles was 13 mm before and 11 mm after ejaculation. The seminal vesicle volume was significantly diminished after ejaculation (p < 0.05). It therefore seems important to maintain a period of abstinence when evaluating the seminal vesicles by ultrasonography.

Adult↗
PubMed1992

Seminal plasma transferrin concentration: relationship with seminal parameters and plasma hormone levels.

Seminal plasma transferrin concentrations were determined in 155 infertile male patients and in 15 pregnancy-proven fertile males (control group); then the relationship between these concentrations and seminal parameters and plasma hormone levels was investigated. The concentrations of seminal plasma transferrin in patients with a sperm concentration below 20 x 10(6)/ml were significantly lower than those in the control group (p < 0.01). There was no significant difference in seminal plasma transferrin concentration between patients with a sperm concentration of 40 x 10(6)/ml or more and the control patients. A positive correlation was observed between sperm concentration and seminal transferrin content (r = 0.56; p < 0.05). However, correlations between seminal transferrin concentration and sperm motility and between seminal plasma transferrin content and sperm morphology did not show any significance, nor did the seminal transferrin content correlate with plasma LH, FSH, prolactin or testosterone levels. It, therefore, seems that while transferrin is indicative of certain physiopathological conditions in the germ cells, this protein is not a distinctive marker of the fertility potential of an individual.

Adult↗
PubMed1992

Paracrine effect of folliculo-stellate cells on the growth factor-like action of activin A in anterior pituitary cultures.

Several studies have shown that pituitary folliculo-stellate (FS) cells exhibit local functions within the pituitary gland. On the other hand, we have shown previously that activin A increases the number of FSH-producing gonadotropes in cultured rat anterior pituitary cells. In this study, we investigated whether FS cells exert an influence on the action of activin A. FS cells were prepared by culturing the dispersed rat anterior pituitary cells in media containing 15% fetal calf serum and 6 mM glutamine for 15 days. Most cells had the morphological characteristics of FS cells and S-100 protein immunoreactivity, a specific marker of FS cells. The number of FSH cells, which was higher in activin A-treated than in control cultures, was reduced to the control level by incubation with activin A plus conditioned media from FS cell-enriched cultures (FSCM). This inhibitory effect of FSCM was neutralized by a follistatin antibody, but not by anti-S-100 protein or anti-basic fibroblast growth factor. Furthermore, follistatin suppressed activin A stimulated increases in the number of FSH cells in a similar inhibitory pattern to that of FSCM. Meanwhile, the number of FSH cells was not affected by FSCM or follistatin in the absence of activin A. These results suggest that FS cells are involved in the regulation of the function and/or the morphogenesis of the FSH cell-lineage by affecting the action of activin A, and that this paracrine effect of FS cells is mediated by follistatin.

Activins↗
PubMed1992

[Trial of in vitro fertilization via epididymal duct aspirated sperm].

We made a trial of our method by which sperm are collected directly from epididymal duct, then subjected to in vitro fertilization. The subjects were a total of 22 cases comprising 14 of obstructed azoospermia and 8 of severe oligoasthenozoospermia, on which the surgery was performed 26 times. Using the microscope, an epididymal duct was directly punctured to make a suction of the fluid or was slightly incised to make a suction of the outflow. Sperms thus collected were preincubated for 4 to 6 hours, then subjected to in vitro fertilization. Condition of collected sperms; 32 x 10(4)-15300 x 10(4) sperms were obtained in real number. Sperm motility rate was 0-82%, averaging 25.0%. Sperm forward motility were fairly good in 18 of 26 test cases. Sperm condition was so poor as to make the insemination impossible in 4 test cases (16%). Fertility rate for cases of obstructed azoospermia was 53% (8/15 test cases) and 63% (55/87 eggs) in the test cases and the number of eggs, respectively, compared with 33% (2/6 test cases) and 5.4% (2/37 eggs), respectively for cases of oligo-asthenozoospermia. Pregnancy; Successful pregnancy was obtained in 2 of the cases of obstructed azoospermia, in each of which sperms were collected from the head of the epididymis, then passed into the maternal body by zygote intra fallopian tubal transfer (ZIFT); with the one case resulting in uneventful delivery in November 1991 and the other in a miscarriage. The above results suggested the present method would become an epoch-making approach in the treatment of severe male infertility.

Epididymis↗
PubMed1992

Galacardins A and B, new glycopeptide antibiotics.

A strain of actinomycetes identified as Saccharothrix sp. SANK 64289 was found to produce new antibiotics, galacardins A and B. Their physico-chemical properties showed that they were new members of glycopeptide antibiotics. They were structurally related to beta-avoparcin but differed from it only in sugar composition. Though beta-avoparcin does not contain galactose, galacardins A and B did contain two and one moles of galactose, respectively. They showed strong antimicrobial activity against Gram-positive bacteria and also showed excellent in vivo protective activity against Staphylococcus aureus infection in mice.

Actinomycetales↗
PubMed1992

Isolation and characterization of new peptide antibiotics, plusbacins A1-A4 and B1-B4.

New antibiotics, plusbacins A1-A4 and B1-B4, were isolated from the culture broth of a strain of Pseudomonas sp. These antibiotics were isolated as a complex by column chromatographies on Diaion HP-20 and silica gel, and then separated by HPLC. They are amphoteric in nature. The hydrochlorides are obtained as colorless powders, soluble in methanol and alkaline water. From their physico-chemical properties, these antibiotics are presumed to be acyloctapeptides containing a lactone linkage, and their differences occur in amino acid and fatty acid residues. The antibiotics are active against Gram-positive bacteria in vitro and in vivo.

Amino Acids↗
PubMed1992

Structures of new peptide antibiotics, plusbacins A1-A4 and B1-B4.

The constituent amino acids of plusbacins A1-A4 were determined to be two moles of L-trans-3-hydroxyproline and one mole each of D-threo-beta-hydroxyaspartic acid, L-threo-beta-hydroxyaspartic acid, D-allo-threonine, D-serine, D-alanine and L-arginine. In plusbacins B1-B4, one mole of L-trans-3-hydroxyproline is replaced by L-proline. The fatty acid residue of A1 and B1 was determined to be 3-hydroxy-tetradecanoic acid, for A2 and B2 to be 3-hydroxy-isopentadecanoic acid, for A3 and B3 to be 3-hydroxy-isohexadecanoic acid, and for A4 and B4 to be 3-hydroxy-hexadecanoic acid. A lactone linkage was suggested to reside between L-threo-beta-hydroxyaspartic acid and 3-hydroxy-fatty acid residues by degradation experiments. The amino acid sequences of plusbacins A2 and B2 were confirmed by Edman degradation of their deacylated products, and supported by mass spectrometric studies. From the above, structures of all components of plusbacins were concluded.

Amino Acid Sequence↗