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Biomedical subjects

K Tajima

Publications and source records attributed to K Tajima.

At least 487 records · Page 27Linked to original sources
PubMed1983

Isotope effects on the metabolism and pulmonary toxicity of butylated hydroxytoluene in mice by deuteration of the 4-methyl group.

A comparative test in mice for pulmonary toxicity between butylated hydroxytoluene (2,6-di-tert.-butyl-4-methylphenol, BHT) and 2,6-di-tert.-butyl-4-[alpha, alpha, alpha-2H3]methylphenol (BHT-d3) showed a significantly lower toxic potency of the latter. The rate of in vitro BHT metabolism to 2,6-di-tert.-butyl-4-methylene-2,5-cyclohexadienone (BHT-QM) was slowed by deuterating BHT in the 4-methyl group. On the other hand, the rate of in vitro metabolism to 2,6-di-tert.-butyl-4-hydroxy-4-methyl-2,5-cyclohexadienone (BHT-OH) was increased with the deuteration. A similar isotope effect of the deuterium substitution on the in vivo metabolic rates of BHT was observed. These observations support the concept that the lung damage caused by BHT is mediated by BHT-QM. The pulmonary toxicity of 2-tert.-butyl-4-ethylphenol (4-EP) and their deuterated analogs was also compared. 2-tert.-Butyl-4-[1,1-2H2]ethylphenol (4-EP-d2) showed a significantly lower toxic potency than 4-EP, whereas 2-tert.-butyl-4-[2,2,2-2H3]ethylphenol (4-EP-d3) showed a toxic potency comparable to that of 4-EP. This result is consistent with the hypothesis that a quinone methide metabolite is responsible for the onset of lung damage produced by 4-EP as well as BHT.

Animals↗
PubMed1983

Serum thyroglobulin changes in patients with Graves' disease treated with long term antithyroid drug therapy.

In 29 patients with thyrotoxic Graves' disease treated with conventional long term antithyroid drug therapy, serum thyroglobulin (Tg) was serially determined by RIA and compared with clinical course, goiter shrinkage, and 131I uptake suppression. Those subjects with Tg autoantibody-negative sera comprised 46% of the patients with Graves' disease. They were divided into a remission group (G I) and an exacerbation group (G II). G I was subdivided into G Ia, who were in remission for 7-40 months, and G Ib, who relapsed more than 15 months after therapy. G II was still on therapy 27-62 months after its initiation, because these subjects exacerbated on reduction of the drugs. Goiter shrinkage occurred in 60% and 0%, and 131I uptakes were suppressed by T3 in 50% and 0% in G I and G II, respectively. Serum Tg in G I declined progressively and reached 48 +/- 5 (+/-SE) ng/ml on discontinuation of therapy, in sharp contrast with serum Tg in G II which remained high throughout (154 +/- 29 ng/ml at the last examination; P less than 0.001). Results of goiter shrinkage, 131I uptake suppressibility, and serum Tg levels were similar in G Ia and G Ib on cessation of therapy. Serum Tg levels less than 68 or more than 140 ng/ml on discontinuation of therapy were helpful in predicting the outcome of therapy. On the other hand, Tg levels were low and goiters were small in size in euthyroid Graves' disease. Tg levels were not clearly correlated with goiter weight or serum T4 and T3 levels before treatment. In conclusion, serial determinations of serum Tg reflect thyroid activity and provide information useful in the decision to discontinue therapy and observation after that.

Adult↗
PubMed1983

[New combination chemotherapy for malignant melanoma--PAV(peplomycin, ACNU, VCR) therapy].

A combination chemotherapy (PAV) consisting of peplomycin, ACNU and vincristine (VCR) was given to 30 patients with malignant melanoma and its therapeutic evaluation was performed. The objective response rate was 42.9% for the patients with stage IV metastatic lesions; three of 7 patients showed improvement. This regimen was particularly effective for both cutaneous and subcutaneous metastatic lesions. When PAV was applied as an adjuvant therapy to the operable cases with stage Ib and II, a five-year survival rate was 50% and the result was far better than that of operation alone. Our results in PAV regimen almost identical with those of DAV(DTIC, ACNU, and VCR) regimen as an adjuvant therapy. The result indicates that PAV regimen is useful for the treatment of malignant melanoma since toxic reactions were mild. Further studies are necessary to assess the efficacy of PAV regimen.

Adult↗
PubMed1983

Seroepidemiological studies on the effects of filarial parasites on infestation of adult T-cell leukemia virus in the Goto Islands, Japan.

Patients with filariasis were commonly observed until 1961-1970 in the Goto Islands, an area where adult T-cell leukemia (ATL) is endemic. The positive rate of antibodies to ATL virus-associated antigen among persons with a high antibody titer to filarial antigen was higher than that among persons with a low antibody titer in both sexes. Thus, filarial parasites might have some promoting effects on ATL virus infection and/or ATL virus proliferation among inhabitants in the endemic areas of filariasis and ATL.

Adolescent↗
PubMed1983

[Epidemiological analysis of adult T-cell leukemia].

Adult T-cell leukemia (ATL) is prevalent in the rural coastal areas of southwestern part of Japan. The geographical distribution of persons with antibody to ATLV which seems to be the decisive causal agent of ATL is very similar to that of ATL patients. The positive rate of anti-ATLA among healthy inhabitants older than 50 years was 32% (21% in males and 39% in females) in Goto Islands in Nagasaki Prefecture. However, positive rates are only 15% in the age group of 30 to 49 years and 4% under 29 years in the same area. From the epidemiological analyses of the mode of anti-ATLA reactivity among married couples and family members with positive and negative anti-ATLA, two routes of transmission of ATLV were suspected. One route is from parents to children and another is the horizontal transmission from new family to woman after marriage. The environmental and socioeconomic factors which had changed remarkably after the World War II and may have influenced the characteristic distribution of ATLV carriers by age and sex in these areas are discussed as the modifying factors for ATLV infection and ATL manifestation from the epidemiological view point.

Adolescent↗
PubMed1983

Epidemiological features of B-cell lymphoma in japan.

Age-adjusted incidence rates for malignant lymphomas in eastern Asian countries except for the Kyushu district of Japan are lower than those in northern European, North and South American and Oceanian countries. Particularly, the incidence rates for Hodgkin's disease and follicular lymphoma are remarkably low in eastern Asian countries. Immunological and clinico-pathological analyses suggested that the estimated rate of incidence of extra-nodal B-cell lymphoma in Japan is not very different from that in the U.S.A. However, their primary sites differ as seen in gastrointestinal lymphomas, most of which are included in extranodal B-cell lymphoma. It is interesting epidemiologically that patients with colorectal lymphoma, whose distribution is closely correlated with that of colorectal cancer in both countries, is much rarer in Japan than in the U.S.A. From the epidemiological viewpoint, extranodal B-cell lymphoma in Japan could be classified by the difference in possible risk factors as follows; lymphoma of the alimentary tract, lymphoma of solid organs, lymphoma of the liver and spleen, medullary or extramedullary plasmacytoma, and Burkitt's lymphoma. In order to clarify the possible risk factors for each type of extranodal B-cell lymphoma including chronic lymphocytic leukemia of B-cell type, it seems necessary to conduct collaborative nationwide epidemiological studies in Japan.

Adult↗
PubMed1983

[Phase I study of forphenicinol, a new biological response modifier].

Forphenicinol, [L-(4-hydroxymethyl-3-hydroxyphenyl) glycine], a new biological response modifier, is a derivative of forphenicine, an inhibitor of chick intestine alkaline phosphatase, discovered by H. Umezawa from the microbial culture filtrate. In order to find an optimal dose schedule of forphenicinol, the drug was given p.o. at doses ranged from 10, 50, 100, 400 to 800 mg once a day for 7 days to 103 patients (39 malignant and 64 benign). No side effect was observed. Statistical analysis was performed on immunological parameters, including WBC; lymphocyte, T-cell, B-cell, T gamma-cell (each % and count); S.I. of PHA and Con A, NK cell activity and K cell activity before and after administration. The patients were divided into the "low-dose" group given less than 100 mg/day of the drug and the "high-dose" group given more than 400 mg/day. Further, on the basis of values of each parameter before administration, the patients were divided into the "low-before" or the "high-before" group, when the pretreated value of parameters was lower or higher than the median of all cases. In the malignant patients, lymphocyte (% and count), T-cell (% and count) and B-cell (% and count) significantly increased in the "low-dose"-"low-before" group (p less than 0.05), but B-cell (%) and S.I. of PHP and Con A decreased in the "low-dose"-"high-before" group. On the contrary, there was no significant change in both the "low-before" and the "high-before" group, when "high-dose" of the drug was given. In the benign patients T gamma-cell (% and count) and NK cell activity were found to be significantly increased in the "high-dose"-"low-before" group, indicating some difference in response of parameter from cancer patients. An optimal dose of forphenicinol for cancer patients was considered to be in a range of 10-100 mg/day.

Adjuvants, Immunologic↗
PubMed1983

[A clinical survey on 24 cases of primary ureteral tumors].

A clinical survey was performed on 24 cases of primary ureteral tumors treated in our University Hospital between Jan. 1972 and Dec. 1981. The incidence of primary ureteral tumors was 0.17% among the outpatients in our urologic clinic. The patients ranged from 41 to 84 years old in age (average age: 65 years), and the male to female ratio was 3 to 1. The left ureter and the lower third of the ureter were involved more frequently. The most frequent initial symptom was macrohematuria seen in 19 cases (79%), followed by loin pain seen in 6 cases (25%). A cytologic study of the voided urine or ureteral urine was carried out in 18 cases and positive results were obtained in 9 cases (50%). Cystoscopic examination revealed a tumor protruding through the ureteral orifice in 16.7% (4 of 24 cases), followed by bulging orifice in 8.3% (2 of 24 cases). Excretory pyelography showed ureteral filling defects in 41.7% (10 of 24 cases). Retrograde pyelography showed ureteral filling defects in 100% (10 of 10 cases). CT showed a mass region in 44.4% (4 of 9 cases). A total of 14 patients underwent nephroureterectomy with partial or total cystectomy (66.7%). The overall 5-year-survival rate was 56.5% and could be directly associated with grade and stage of tumors.

Adult↗
PubMed1983

[Phase I study of Bestatin: (I) A clinical study on determination of an optimal dose of Bestatin].

Bestatin is a low toxic peptide discovered by Umezawa et al. and animal experiments have revealed that Bestatin enhances the immune response to activate the defense mechanism of the living organism, and thus suppresses the growth and metastasis of cancer. Recently we performed a phase I study of Bestatin to determine an optimal dose. Analysis of changes in immunological parameters at all the tested dosages of Bestatin led to the presumption that its optimal dose was in the low dosage ranging from 10 to 100 mg daily. Because the effects of a single administration of Bestatin on immunological parameters disappeared at day 7, 2 or 3 times administration per week or even daily seemed to be required. Hematology, hepatic and renal function tests revealed no apparent adverse reactions which were considered to be derived from Bestatin administration.

Adjuvants, Immunologic↗
PubMed1983

[Current status and problems of gastric cancer in the aged].

Based on our analysis of 1) gastric cancer patients surgically treated between 1972-1980 in Niigata Prefecture, 2) mortality statistics, and 3) 381 gastric cancer patients older than 70 years operated in our hospital, we concluded that 1) The number of geriatric surgical patients with gastric cancer, especially early gastric cancer, is on the increase in Niigata Prefecture. 2) The mortality from gastric cancer has decreased markedly in 70-74 year-old patients, has declined slightly in patient ranging from 75-79 years and has increased in patients over 80 years. 3) In patients between 75-79 years and 70-74 years, surgery as almost equally safe and their long-term survival rate was similar. Our results suggest that gastric cancer patients ranging between 75-79 years should be operated as radically as younger patients.

Aged↗
PubMed1982

Dual effects of catecholamines on pre- and post-junctional membranes in the dog trachea.

1 Effects of noradrenaline or isoprenaline on the membrane and contractile properties of the smooth muscle cell, or on the excitatory neuro-effector transmission in the dog trachea, in vitro, were observed by use of microelectrodes and double sucrose gap methods.2 Noradrenaline (<5 x 10(-6) M) or isoprenaline (<5 x 10(-7) M) modified neither the membrane potential nor the membrane resistance. Increased concentrations of noradrenaline (>5 x 10(-5) M) depolarized and isoprenaline (>5 x 10(-7) M) hyperpolarized the membrane, and these actions were suppressed by phentolamine and propranolol respectively. Both catecholamines reduced the membrane resistance.3 Noradrenaline (5 x 10(-6) M) or isoprenaline (5 x 10(-7) M) reduced the resting tension, raised the mechanical threshold required to produce the contraction and suppressed the amplitude of phasic contractions evoked by electrical depolarization of the membrane.4 The action potential evoked by an outward current pulse in the presence of tetraethylammonium (TEA) was not affected by 5 x 10(-6) M isoprenaline, while the mechanical response was markedly suppressed.5 The excitatory junction potential (e.j.p.) evoked by electrical field stimulation was blocked by atropine. Noradrenaline (5 x 10(-7) M) or isoprenaline (5 x 10(-8) M) suppressed the amplitude of e.j.p. with no change in the membrane potential or input membrane resistance. Depression in the amplitude of e.j.ps produced by noradrenaline or isoprenaline reduced the amplitude of phasic contractions evoked by e.j.ps.6 These inhibitory actions of the catecholamines on mechanical responses and on e.j.ps were suppressed by pretreatment with propranolol (4 x 10(-6) M).7 Dog tracheal smooth muscles are innervated by cholinergic excitatory and adrenergic inhibitory systems. Electrical field stimulation produced excitation of both cholinergic and adrenergic nerve fibres, and propranolol (4 x 10(-6) M) enhanced the amplitude of e.j.p. generated by excitation of cholinergic nerves when repetitive stimulation (10 stimuli at 20 Hz) was used, but not the amplitude of the e.j.p. evoked by a single stimulus.8 5-Hydroxytryptamine (6 x 10(-6) M) produced a tonic contracture of the dog trachea. After pretreatment with atropine (4 x 10(-6) M), field stimulation (50 mus in duration and repetitive stimuli at 20 Hz) induced reversal of the contracture induced by 5-hydroxytryptamine and this was abolished by propranolol (5 x 10(-6) M).9 These results indicate that endogenous or exogenous catecholamines, in relatively low concentrations, predominantly activate beta-adrenoceptors in the pre- and post-junctional membrane in the dog trachea, and induce muscle relaxation.

Animals↗