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Biomedical subjects

H Kubo

Publications and source records attributed to H Kubo.

At least 379 records · Page 21Linked to original sources
PubMed1984

[A case of highly atypical hyperplasia--difficult to differentiate from carcinoma].

We present a 51-year-old nulliparous woman with highly atypical hyperplasia of the uterus induced by the prolonged use of exogenous estrogen. The patient was given nearly 1,415 mg of estradiol dipropionate intramuscularly for over 23 years after operation for bilateral ovarian cysts. She complained of vaginal bleeding and diagnostic endometrial curettage revealed highly atypical hyperplasia which was difficult to differentiate from well differentiated adenocarcinoma. On hysterectomy, atypical tissues were limited to the upper part of the posterior wall of the uterus with no muscle invasion.

Adenocarcinoma↗
PubMed1983

Absorbed dose determination with a water calorimeter in comparison with an ionisation chamber.

The absorbed dose in water has been measured for both photon and electron beams using a water calorimeter. The results were compared with those obtained with a Farmer type ionisation chamber. Doses measured with the water calorimeter for 60Co gamma rays, 10 and 25 MV x-rays, and 16.6 and 22.3 MeV electrons are approximately 4.5 to 5% higher than those derived from ionisation chamber measurements using the formation of ICRU 14 and 21. Based on a new formalism which has been under study, the calorimeter results for gamma and x-rays were found to be approximately 2-4% higher than predictions. For electrons the calorimeter results were approximately 3.5% higher than predictions. The differences found are discussed in terms of the heat defect of water.

Calorimetry↗
PubMed1983

[Combined modality for recurrent and disseminated ovarian cancer--CAPF combination chemotherapy and second-look operation].

Twenty-seven patients with advanced ovarian cancer were treated with CAPF therapy consisting of CPA, ADM, CPDD, and 5-FU. Twenty patients were evaluable for responses. Fourteen patients (70%) had a complete (6 patients) or partial response (8 patients). The median survival time for responders was 12.0+ months and 4.0 for non-responders. Leukopenia and renal toxicity were dose limiting factors. A second-look operation was performed in 12 patients who had favorable results from CAPF. A combined modality with CAPF and second-look operation seemed to be promising.

Adolescent↗
PubMed1982

Reduction of the scatter dose to the testicle outside the radiation treatment fields.

A technique is described to reduce the dose to the contralateral testicle of patients with testis tumors during retroperitoneal therapy with 10 MV X rays. When a conventional clam-shell shielding device was used, the dose to the testis from the photons scattered by the patient and the collimator jaws was found to be about 1.6% of the prescribed midplane dose. A more substantial gonadal shield made of low melting point Ostalloy, that reduced further the dose from internal scattered X rays, was therefore designed. A 10 cm thick lead scrotal block above the scrotum immediately outside the field is shown to reduce the external scattered radiation to negligible levels. Using the shield and the block, it is possible to reduce the dose to the testicle to one-tenth of one percent of the prescribed midplane dose.

Alloys↗
PubMed1982

Use of 10 MV spoiled x ray beam for treatment of head and neck tumors.

The employment of a 10 MV X ray beam for treatment of head and neck tumors has been investigated. A 1.2 cm thick beam spoiler positioned 7 cm from the patient surface was used to achieve adequate dose to the superficial region. This technique provides at least 90% depth dose at 0.5 cm depth, which is clinically required for the treatment. For departments able to acquire only one megavoltage machine, the technique can provide an option to treat adequately both shallow as well as deep-seated tumors by choosing a high megavoltage machine; a low megavoltage machine cannot provide an equivalent option to treat deep-seated tumors.

Acrylic Resins↗
PubMed1982

Trace element abnormalities in chronic uremia.

We studied the elemental composition of autopsy tissue samples to characterize the trace element changes induced in various human tissues by uremia. Samples from the United States and Australia, including those from 120 uremic patients who had been on dialysis, 29 uremic patients who had not been on dialysis, and 64 control subjects, were analyzed by x-ray fluorescence. Tissues analyzed were aorta, bone, brain, heart, kidney, liver, lung, muscle, and spleen; elements measured included potassium, calcium, iron, copper, zinc, selenium, bromine, rubidium, strontium, molybdenum, cadmium, tin, and uranium. Uremic abnormalities that were statistically very significant were found, including increases of calcium, strontium, molybdenum, cadmium, and tin and decreases of potassium and rubidium. The distribution of iron, copper, and zinc are altered. We conclude that these abnormalities are primarily the result of the uremia and that, generally, they are neither greatly moderated nor exacerbated by the dialysis procedure.

Adolescent↗
PubMed1982

Plasminogen activator activity in mouse embryos cultured on decidual cell monolayers.

The nature of proteolytic activity in the mouse blastocyst was investigated in vitro using cell monolayers as a substrate. Blastocysts obtained from mice on day 4 of gestation were placed directly on various types of cell monolayers. The embryos had hatched at 34 hrs, attached at 45 hrs, and at 56 hrs of culture they formed trophoblast outgrowths by displacing the underlying monolayer cells. Because blastocysts developed equally well on all types of cell monolayers tested, a decidual cell monolayer was used in all the following experiments. The plasminogen activator activity in blastocysts was examined using the fibrin-agar overlay assay. There was a strong relationship between the levels of activity and the extent of trophoblast outgrowth. At the hatching stage, 20% of the embryos showed fibrinolysis, whereas 86% showed clear fibrinolysis at the trophoblast outgrowth stage. After the loss of invasiveness, only 32% of them showed fibrinolysis. Lysed zones surrounding trophoblast always extended beyond the area which displaced the previously occupied cell monolayer. We never observed a clear zone (halo) between the trophoblast and monolayer cells nor cytolytic activity inside the fibrinolytic zone until the embryos had lost their invasive nature.

Animals↗
PubMed1981

Inhibition of mouse blastocyst attachment and outgrowth by protease inhibitors.

Effects of protease inhibitors on development of mouse blastocysts and fibrinolytic activity of trophoblast were examined by growing embryos on monolayers of decidual cells in the presence of inhibitors. Nitrophenol-p-guanidino benzoate (NPGB) was the most effective inhibitor; 10(-4) M NPGB inhibited attachment and trophoblast outgrowth by 24% and 66%, respectively, and inhibited the fibrinolytic activity of trophoblast by 86%. The effects of NPGB were reversible, as demonstrated by the embryos' ability to attach and resume normal development when transferred to NPGB-free medium. Soybean trypsin inhibitor and epsilon-aminocaproic acid were less effective than NPGB in inhibiting blastocyst development. When 10(-4) M NPGB and 350 microgram/ml of soybean trypsin inhibitor were added together, blastocyst development and fibrinolytic activity were inhibited more severely than when either inhibitor was added alone. We suggest that at least two types of proteolytic activities in mouse blastocysts are involved in implantation, attachment requiring trypsin-like activity, and trophoblast outgrowth requiring both plasminogen activator and trypsin-like activity.

Animals↗
PubMed1981

A simple method of x-ray fluorescence analysis in hair.

A simple X-ray fluorescence (XRF) analysis method has been developed for the determination of trace element concentrations in hair. It utilises strands of hair which are dropped on a Formvar foil and irradiated in an X-ray beam. The effective sample mass was estimated by measuring scattered X-ray photons. The attenuation correction for the X-rays from light elements was estimated using a simple model. Results are in agreement with those obtained by the atomic absorption method.

Hair↗
PubMed1981

Tissue distribution of isoniazid and its metabolites in rats.

Distribution of isoniazid and its metabolites was observed in the liver, kidney, lung and plasma after the subcutaneous administration of isoniazid to rats. The tissue levels of isoniazid, acetylisoniazid, acetylhydrazine, 1,2-diacetylhydrazine and hydrazine were determined by mass fragmentography using a gas chromatograph-mass spectrometer equipped with a multiple ion detector-peak matcher. Using the compounds labeled with a stable isotope as an internal standard, namely the isotope dilution method, made it possible to estimate trace amounts of these metabolites in the tissues. The amount of hydrazine was much less than the other hydrazines, but the metabolite which is well known as a mutagen, could be successfully detected in the tissues and plasma. The greater part of free hydrazine is formed through a direct hydrolysis of isoniazid. The isoniazid-hydrolyzing activity was found to be significantly higher in the liver homogenate. This suggested that hydrazine formation is mainly caused by hepatic hydrolysis.

Absorption↗
PubMed1980

Acute nickel intoxication by dialysis.

Nickel intoxication was observed in a group of 23 dialyzed patients when leaching of nickel-plated stainless steel water heater tank contaminated the dialysate. Symptoms occurred during and after dialysis at plasma nickel concentrations of approximately 3 mg/L. Symptoms included nausea (37 of 37), vomiting (31 of 37), weakness (29 of 37), headache (22 of 37), and palpitation (two of 37). Remission of symptoms occurred spontaneously, generally 3 to 13 hours after cessation of dialysis. The evidence indicated that the nickel became bound in the plasma after crossing the membrane, resulting in a higher concentration in the plasma than in the dialysate and preventing its removal by dialysis.

Heating↗
PubMed1979

Competitive nephelometric immunoassay of theophylline in plasma.

We have developed an accurate, simple, and rapid method for the determination of theophylline in plasma. The principle of the method is based on inhibition of immunoprecipitation by hapten. A nephelometer is used to measure the scattered light from the immunoprecipitate. The macromolecule, which possesses numerous theophylline moieties and forms immunoprecipitate with anti-theophylline antibodies, can be easily prepared and used as the reagent for the assay. Theophylline in the assay mixture competitively inhibits the immunoprecipitation of the macromolecule. Therefore, theophylline can be determined by the measurement of the decrease of the scattered light. The assay is rapid (incubation time within 15 min), requires as little as 10 microliter of plasma, and requires neither troublesome pretreatment nor separation of antibody-bound from free antigen. Estimations of theophylline levels in patient plasma specimens correlate well to those obtained by the high performance liquid chromatography (correlation coefficient 0.971).

Densitometry↗
PubMed1979

Competitive nephelometric immunoassay method for antiepileptic drugs in patient blood.

We established a competitive nephelometric immunoassay method for the determination of the widely used antiepileptic drugs, phenobarbital and diphenylhydantoin, in human blood plasma. The anti-drug antiserum was collected from the immunized rabbit. The human serum albumin possessing numerous drug moieties was easily prepared for the assay reagent. A laser nephelometer was used to measure the scattered light from the immunoprecipitate. The assay was rapid (incubation time 10 min), required as little as 6 microliters of plasma, required neither troublesome pretreatment nor separation procedure. The patients' plasma specimens were analyzed, and the values correlated well to those determined by the high-performance liquid chromatography (correlation coefficient: 0.983 for phenobarbital, 0.987 for diphenylhydantoin).

Animals↗