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Biomedical subjects

M Koyama

Publications and source records attributed to M Koyama.

At least 235 records · Page 13Linked to original sources

[Studies on the clinical significance concerning the changes in serum pepsinogen-I and gastrin levels in aged patients with chronic gastritis].

Of 86 cases of aged patients with chronic gastritis treated with Trimebutine or Flutazolam, we evaluated the changes of serum pepsinogen-I and gastrin levels in their clinical courses from the points of the correlation with severity of chronic gastritis, aging phenomenon and the changes of symptom and endoscopic findings. In order to elucidate the multidimensional interrelation among these items, we used Hayashi's quantification theory II as a conventional analysis method. In aged patients, generally, although the serum gastrin levels were rather high compared with younger generation, the serum pepsinogen-I levels were consistently low throughout their clinical courses. There were some correlation between the levels of serum gastrin and the severity of chronic gastritis. When the drugs were effective on improving the condition of the disease, the level of gastrin revealed gradual decrease. These changes of gastrin were more typical in patients treated with Trimebutine.

Aged↗

Occurrence of vanadium ion in serum albumins.

Vanadium was shown to be a contaminant in Sigma-grade serum albumins, fraction V. The levels of vanadium detected by neutron activation analysis were: bovine 16.7, ovine 10.0, rabbit 9.1, porcine 3.9, and human 0.19 micrograms/g protein. According to the ESR spectra, the vanadate form (+5 oxidation state) was strongly suggested as a chemical form present in albumins. Dialysis against a chelating agent was quite effective for removal of the metal ion.

Animals↗

Synthesis and quantitative structure-activity relationship analysis of N-triiodoallyl- and N-iodopropargylazoles. New antifungal agents.

New series of N-(2,3,3-triiodoallyl) and N-(3-iodopropargyl) azole derivatives (100 compounds) involving pyrrole, pyrazole, imidazole, triazole, and tetrazole nuclei were synthesized successively with the aid of quantitative structure-activity relationship (QSAR) analysis to obtain potent antifungal agents. Starting from the derivatives of nitropyrrole-containing antibiotics, the QSAR analysis of the pyrrole derivatives against Candida albicans and Trichophyton mentagrophytes strains indicated the positive contribution of the nitro group and negative effect of the size of molecule. Further application of the QSAR analysis on the multi-azole derivatives revealed the importance of hydrophobicity and electronegativity as well as steric effect to the activities and led to the synthesis of one of the most potent iodo compounds, 2-(2,3,3-triiodoallyl)tetrazole (67, ME1401).

Allyl Compounds↗

Effect of a soluble factor secreted from cultured human trophoblast cells on in vitro lymphocyte reactions.

The immunoregulatory role of trophoblast cells in cell-mediated immunity was investigated. Trophoblast cells were obtained from 8-10-week human placentae by treatment with collagenase followed by differential centrifugation. The cells were cultured for 48 hr, and the culture supernatant was examined for immunosuppressive activity in vitro. The supernatant when added to cultures of peripheral blood lymphocytes from healthy donors suppressed both their reactivity to different lectins (PHA and PWM) and their activity in one-way mixed lymphocyte reaction. The degree of suppression was dose-dependent. Furthermore, the supernatant was able to reduce the natural killer cell activity against K562 target cells. On the other hand, the supernatant had no inhibitory effect on the effector phase of lymphocyte-mediated cytotoxicity activity against tumor cell lines RPMI 8866 and Daudi. In all cases, the suppression observed was not due to lymphocytotoxicity or tumor cell mortality. The results indicate that trophoblast cells release a soluble suppressive factor that is a potent inhibitor of cell-mediated immunity.

Cytotoxicity, Immunologic↗

[ELISA for antisperm antibodies in unexplained infertile women].

It is commonly believed that autoimmune or isoimmune responses to human sperm antigens are associated with human infertility. We examined an enzyme linked immunosorbent assay (ELISA) kit used in the detection of antisperm antibodies in the sera of women with unexplained infertility. 1) For the ELISA assay, an absorbance at 405nm greater than 0.300 was considered positive. Of the 83 sera of infertile women studied, 20(24.1%) were positive. This value was significantly higher than that of the control group: 10% of pregnant women, 11.1% of unmarried women and 10% of healthy men (p less than 0.05). 2) The results obtained with ELISA were compared with those of the sperm immobilization test. Comparison of the results of ELISA with those of the sperm immobilization test indicated that these methods detect a different, though often overlapping, spectrum of antibody activity. 3) The results obtained with ELISA did not always correlate with those of the Huhner test. However the ELISA method may be useful in the clinical screening of antisperm antibodies because of its simplicity and rapidity.

Adult↗

[Clinical phase I study of T-2588].

A clinical phase I study for T-2588 was carried out in 25 healthy male volunteers. Each volunteer received T-2588 in one of the following doses: 100 mg capsule or tablet as a single oral administration in fasting or non-fasting state, 200 or 400 mg capsule as a single oral administration in non-fasting state or 300 or 600 mg daily for 14 approximately 15 days as a repeated administration in non-fasting state. The results are summarized below. No subjective or objective adverse effects were noted after a single oral administration. But repeated dose of 300 mg daily for 15 days and 600 mg daily for 14 days brought about abdominal distension in 1 case and soft stool in 1 case, respectively. As an abnormal change in clinical laboratory findings, 1 case with slight increase in transaminase after a single administration and 3 cases with slight increases in transaminase after repeated doses were observed. Time to reach a maximum concentration of T-2525 in blood (Tmax) was longer in subjects at non-fasting states than subjects in fasting states. Maximum blood concentration was lower in the latter than in the former. Urinary excretion rate in 8 hours after an oral administration was 19 approximately 28% and it was higher in non-fasting subject than in fasting subject. No accumulation of T-2588 was noted after repeated doses.

Administration, Oral↗

An improved colorimetric assay for interleukin 2.

Mosmann's method for measuring the number of viable cells with a tetrazolium salt, 3-(4,5-dimethylthiazol-2-yl)-2,5-di-phenyltetrazolium bromide (MTT), was modified to make it possible to measure a large number of interleukin 2 (IL-2) samples at one time with less labor and more accuracy. Each step of the method was examined in detail and modified (the modified MTT method). An IL-2-dependent mouse natural killer cell line, NKC3, was used as an indicator cell line. The incubation period before adding MTT was reduced to 24 h, A solution of 10% sodium dodecyl sulfate-0.01 N HCl was used to dissolve the MTT formazan produced. We have compared the values obtained by the modified MTT method and the conventional [3H]thymidine method (3H-TdR method), and confirmed that the estimates of IL-2 content were almost equal. The variation of IL-2 content measured by both methods was within 5% in terms of the standard error.

Cells, Cultured↗

Immune complex containing herpesvirus antigen in a patient with acute retinal necrosis.

A 21-year-old man with acute retinal necrosis showed a marked increase in the convalescent titer to herpes simplex type 1 virus, especially in the aqueous humor obtained by anterior chamber paracentesis. Using an enzyme-linked immunosorbent assay, we tried to detect the herpesvirus antigen in the circulating immune complex obtained from this patient. The immune complex contained an antigen or antigens that reacted with antiherpes simplex type 1 antibody.

Acute Disease↗

[Clinical study of chemotherapy (PPM therapy) with cisplatin, peplomycin and mitomycin C in squamous cell lung cancer].

The effect of PPM therapy, consisting of cisplatin, peplomycin and mitomycin C, was evaluated in 15 cases of squamous cell lung cancer. Ten partial responses were achieved in primary cases and the response rate was 66.7%. Nephrotoxicity was well controlled with a continuous infused drip and FOM. The nausea and vomiting were reasonably well controlled with methylprednisolone and metoclopramide. Severe interstitial pneumonitis occurred in 5 cases (33.3%). PPM therapy is considered to be a very useful combination chemotherapy for squamous cell lung cancer but careful attention must be paid to pulmonary toxicity.

Aged↗

Immunological studies of uveitis. 3. Cell-mediated immunity to interphotoreceptor retinoid-binding protein.

Three patients were seen with the same clinical characteristics which were not described previously: diffuse uveitis with bilateral involvement, onset in the second decade of life, no extraocular signs or symptoms, diffuse retinal capillary leakage on fluorescein angiography but without apparent fundus changes, many vitreous cells but no snowbank-like vitreous opacity, responsiveness to steroid, and good prognosis. The peripheral blood lymphocytes of all three patients responded to bovine and human interphotoreceptor retinoid-binding protein (IRBP), but not to bovine retinal S antigen. It was speculated that these patients were human counterparts of IRBP-induced uveoretinitis that was described in experimental animals.

Adolescent↗

[Obstetric factors associated with intracranial hemorrhage (ICH) in premature infants and antenatal prediction of ICH].

Obstetric factors associated with intracranial hemorrhage (ICH) were evaluated in 98 inborn premature infants of less than 1,500 gm birth weight or less than 32 weeks of gestation. ICH was detected in 25 (25.5%) of these infants by ultrasound sonography and/or computed tomography. No association of obstetric factors such as maternal age, parity, gravidity, premature rupture of the membrane, toxemia, placenta previa, fetal position, mode of delivery or fetal sex with ICH was noted. But the ICH group showed a higher incidence of placental abruption, infarction, infection and incompetent cervix than the non-ICH group. In addition, gestational ages and birth weights were less in the ICH group than in the non-ICH group, although differences were not significant except for the group with incompetent cervix (p less than 0.05). However, Apgar scores and FHR scores according to Krebs et al. for the ICH group were significantly lower than those for the non-ICH group. The two groups were distinguished by multivariable discriminant analysis of FHR scores, birth weights and gestational ages (discriminant efficiency, 3.74: F-value, 20.6: true positive ratio, 81.3%). These results suggested that antenatal prediction of ICH in premature infants was possible, but further studies are needed to elucidate the reliability of its prediction.

Adult↗