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Biomedical subjects

H Misaki

Publications and source records attributed to H Misaki.

At least 37 records · Page 2Linked to original sources

[Treatment of scrotal hydrocele using fibrin adhesive].

For the purpose of adhesion of the tunica vaginalis in scrotal hydrocele, we used fibrin adhesive, Bolheal. Between September 1993 and December 1994, 13 patients with scrotal hydrocele received occlusion therapies using Bolhead. The therapy was effective in 1 of the 6 patients (17%) administered 2.4 mg of fibrinogen and 750 units of thrombin into the vaginal cavity after aspiration of fluids, and in 5 of the 7 patients (71%) administered 240 mg of fibrinogen and 7.5 units of thrombin. Therefore, fibrin adhesive may be useful in the treatment of scrotal hydrocele.

Aged↗

Comparable sensitivities for detection of HIV-1 reverse transcriptase (RT) and other polymerases by RT assays requiring no radioisotopic materials.

An improved non-radioisotopic (Non-RI) reverse transcriptase (RT) assay with a template-primer-immobilized microtiter plate is described, which has greater sensitivity than the former Non-RI RT assay previously described. Non-RI and commercially available non-radioactive (Non-RA) RT assays were compared for their ability to detect various polymerases. Two RTs from Rous-associated virus 2 (RAV-2) and avian myeloblastosis virus (AMV), one polymerase from Escherichia coli (Pol-I) and one recombinant RT of human immunodeficiency virus type 1 (HIV-1) were assessed. Two HIV-1 samples in a culture supernatant and pelleted virion suspended in Triton X-100 solution were measured. The Non-RI RT assay was one hundred times more sensitive by RAV-2 and Pol-I polymerases, and one thousand times more sensitive by the Non-RA assay than by the AMV RT. The Non-RI RT assay was 10, 16 and 64 times more sensitive than the Non-RA assay for measuring recombinant HIV-1 RT, pelleted virus and virus suspended in culture medium, respectively. To explain the discrepancy, it is shown that free biotin, such as in culture medium, disturbs the assay system of the Non-RA RT assay, but not the Non-RI assay. The present assay can be used to clarify the inhibitory mechanism of an anti-HIV-1 substance.

Animals↗

L-lactate oxidase and L-lactate monooxygenase: mechanistic variations on a common structural theme.

Properties of L-lactate oxidase from Aerococcus viridans are described. The gene encoding the enzyme has been isolated. From its cDNA sequence the amino acid sequence has been derived and shown to have high similarity with those of other enzymes catalyzing oxidation of L-alpha-hydroxy acids, including flavocytochrome b2, lactate monooxygenase, glycolate oxidase, mandelate dehydrogenases and a long chain alpha-hydroxy acid oxidase. The enzyme is expressed in Escherichia coli, and is a flavoprotein containing FMN as prosthetic group. It shares many properties of other alpha-hydroxy acid oxidizing enzymes, eg stabilization of the anionic semiquinone form of the flavin, facile formation of flavin-N(5)-sulfite adducts and a set of conserved amino acid residues around the bound flavin. Steady-state and rapid reaction kinetics of the enzyme have been studied and found to share many characteristics with those of L-lactate monooxygenase, but to differ from the latter in quantitative aspects. It is these quantitative differences between the two enzymes which account for the differences in the overall reactions catalyzed. These differences arise from different stabilities of a common intermediate of reduced flavin enzyme and pyruvate. In the case of the monooxygenase this complex is very stable and is the form that reacts with O2 to give a complex in which the oxidative decarboxylation occurs, yielding the products, acetate, CO2, and H2O (Lockridge O, Massey V, Sullivan PA (1972) J Biol Chem 247, 8097-8106). With lactate oxidase, the complex dissociates rapidly, with the result that it is the free reduced flavin form of the enzyme that reacts with O2, to give the observed products, pyruvate and H2O2.

Amino Acid Sequence↗

Differential expression of protooncogenes in human germ cell tumors of the testis.

BACKGROUND: It has been suggested that tumorigenesis of the germ cell tumor of the testis includes abnormal and developmentlike differentiation of primordial germ cells to several mature type tumors. METHODS: To clarify roles of protooncogenes in the unique tumorigenic mechanism in the human germ cell tumor, the authors examined the expression of 15 protooncogenes in human primary germ cell tumors of the testis with Northern blot analyses. RESULTS: Fifteen (94%) of 16 seminomas and 5 (83%) of 6 embryonal carcinomas had a significant levels of N-myc expression, whereas they did not express two receptor type protooncogenes, c-erbB-1 and c-erbB-2. In contrast, some immature teratomas had a high level of c-erbB-1 expression, and an advanced case showed a significant level of c-erbB-2 expression. Immature teratomas did not show N-myc expression. Higher levels of c-mos expression were observed in several cases of seminomas and embryonal carcinomas. Expression of c-Ki-ras or N-ras was observed in all histologic subgroups and normal testes. CONCLUSION: A significant level of N-myc expression may be essential for undifferentiated tumors including seminoma and embryonal carcinoma, whereas c-erbB-1 and possibly c-erbB-2 may have important roles in the differentiated tumors such as immature teratoma. These results suggest that some of the protooncogene expression may be switched critically during the differentiation from seminomas or embryonal carcinomas to the more differentiated-type tumor.

Biomarkers, Tumor↗

Acylcarnitine deficiency in chronic fatigue syndrome.

One of the characteristic complaints of patients with chronic fatigue syndrome (CFS) is the skeletal muscle-related symptom. However, the abnormalities in the skeletal muscle that explain the symptom are not clear. Herein, we show that our patients with CFS had a deficiency of serum acylcarnitine. As carnitine has an important role in energy production and modulation of the intramitochondrial coenzyme A (CoA)/acyl-CoA ratio in the skeletal muscle, this deficiency might induce an energy deficit and/or abnormality of the intramitochondrial condition in the skeletal muscle, thus resulting in general fatigue, myalgia, muscle weakness, and postexertional malaise in patients with CFS. Furthermore, the concentration of serum acylcarnitine in patients with CFS tended to increase to the normal level with the recovery of general fatigue. Therefore, the measurement of acylcarnitine would be a useful tool for the diagnosis and assessment of the degree of clinical manifestation in patients with CFS.

Acyl Coenzyme A↗

An improved non-radioisotopic reverse transcriptase assay and its evaluation.

We developed an improved, highly sensitive non-radioisotopic (non-RI) reverse transcriptase (RT) assay (RTA). While the original non-RI method previously reported made use of primer immobilization, our improved method was based on a primer-template immobilization procedure. We tested the template specificity, reproducibility and linearity of the new method in assays of human immunodeficiency virus type-1 (HIV-1) RT. The sensitivities of the method previously reported, the improved method and the sensitive radioisotopic (RI-) RTA were compared in assays of recombinant HIV-1 RT, partially purified HIV-1 particles, and the culture supernatant derived from HIV-1-infected cells. For each of these samples except the culture supernatant the improved method was the most sensitive. It appeared that the fetal bovine serum presented in the culture medium interfered with the assay reaction. The curve describing inhibition of the assay reaction by fetal bovine serum showed that the highest degree of sensitivity in the assay was obtained when the culture supernatant sample was diluted four times. With this degree of dilution, the sensitivity of the new method for assay of culture supernatant sample was still half that of the sensitive RI-RTA. Culture supernatants of five peripheral blood mononuclear cell samples obtained from HIV-1-seropositive carriers were assayed by both the improved method and the sensitive RI-RTA; and with each of the methods, however all virus-positive cultures could be detected. The improved non-RI RTA was considered especially useful for assay of culture supernatants for purposes of virus isolation because of its advantages of excellent sensitivity and lack of requirement for radioisotopes.

HIV Reverse Transcriptase↗

Differentiation between human immunodeficiency virus type 1 (HIV-1) and HIV-2 isolates by nonradioisotopic reverse transcriptase-typing assay.

We tested whether human immunodeficiency virus type 1 (HIV-1) could be differentiated from HIV-2 by a reverse transcriptase (RT)-typing assay that measured the reduction of enzyme activity owing to specific antibody. RT-inhibiting antibody was examined for HIV type specificity by a new nonradioisotopic RT assay. Antibodies from four rabbits immunized with recombinant HIV-1 RT and from 23 HIV-1-seropositive individuals all specifically inhibited the enzyme activities of two HIV-1 strains (LAV-1 and GH-3), three zidovudine-resistant HIV-1 mutants, and a recombinant HIV-1 RT. However, none of these antisera affected the activities of six HIV-2 strains (GH-1, GH-2, GH-4, GH-5, GH-6, LAV-2ROD), Rous-associated virus type 2, and DNA polymerase I from Escherichia coli. In contrast, HIV-2 antibody from a rabbit immunized with disrupted GH-1 virions blocked the enzyme activities of the six HIV-2 strains but not those of the three HIV-1 strains, Rous-associated virus type 2, or DNA polymerase I. These results indicate that the antigenic domains of HIV-1 and HIV-2 RTs recognized by their inhibiting antibodies are distinct from each other and are highly conserved. Clinical HIV isolates from 18 HIV-1-seropositive individuals and 3 HIV-2-seropositive Ghanaian individuals were identified as HIV-1 and HIV-2, respectively, by the nonradioisotopic RT-typing assay.

Antibodies, Viral↗

[M-VAC chemotherapy for advanced urothelial cancer--side effects and their management].

Since the M-VAC (methotrexate, vinblastine, doxorubicin, cisplatin) regimen was reported by Sternberg in 1985, it has been widely accepted for the treatment of metastatic transitional cell carcinoma. This regimen has a significantly high response rate, but bone marrow suppression and gastrointestinal (GI) symptoms are inevitable. To complete this M-VAC regimen, preventive therapy for side effects is necessary. From November 1986 to March 1993, a total of 72 patients were admitted and received M-VAC therapy at our hospital. All of them had metastatic or invasive transitional cell carcinoma and they received a total of 163 complete courses of M-VAC therapy. We examined the side effects of this M-VAC regimen, and evaluated the effectiveness of colony-stimulating factor for prevention of granulocytopenia or granisetron for prevention of GI symptoms. Twenty-three patients (39 courses) were given recombinant colony-stimulating factor. This cytokine prevented the nadir of neutropenia and shortened the period to reach the nadir and period that the neutrophil count was below 1,000/mm3. Twelve patients (26 courses) were given granisetron, with significant reduction of the incidence of GI symptoms. These findings suggest that M-VAC therapy is effective and safe when used in combination with these drugs.

Adult↗

[Ask-Upmark kidney: a case report].

A case of Ask-Upmark kidney is presented. An 18-year-old male patient referred to this facility presented with symptoms of hypertension, microscopic hematuria and proteinuria. A hormonal study revealed a high plasma renin activity level. Intravenous pyelography and abdominal computed tomography revealed thinning of the cortex with calyceal dilatation. Arteriography revealed a deep cortical groove in the middle portion of the kidney without renal arterial stenosis. Plasma renin activity of the left renal vein was significantly higher than that of the right renal vein. A left simple nephrectomy was performed under the diagnosis of Ask-Upmark kidney. Postoperatively, plasma renin activity returned to the normal range and a decrease in blood pressure was noted. Recent reports have suggested Ask-Upmark kidney to be a consequence of vesicoureteral reflux rather than a true congenital malformation. Our case indicated no evidence of vesicoureteral reflux and suggests that the lesion was congenital rather than acquired.

Adolescent↗

Carnitine determination by an enzymatic cycling method with carnitine dehydrogenase.

We describe a highly sensitive and specific method for determining L-carnitine in serum by use of carnitine dehydrogenase (EC 1.1.1.108). The method involves a new enzymatic cycling technique with NADH, thio-NAD+, and carnitine dehydrogenase, and measures the increase of absorbance at 415 nm of thio-NADH produced at 37 degrees C during the reaction: [formula: see text] The calibration curve for L-carnitine in serum was linear between 5 and 250 mumol/L. Analytical recovery was 96.5-106%, and within-run and between-run imprecisions (CV) were 0.66-4.33% and 1.02-2.56%, respectively. This method was free from interference by bilirubin, hemoglobin, various acyl-DL-carnitines, and ascorbate. The procedure is simple, rapid, accurate, and automatable. The amount of free L-carnitine in serum (53.6 +/- 11.7 mumol/L, n = 200) was greater in men than in women (45.1 +/- 14.2 mumol/L, n = 200) (mean +/- SD).

Alcaligenes↗

Enzyme reactor for urinary acylcarnitines assay by reversed-phase high-performance liquid chromatography.

An immobilized enzyme reactor, made up acylcarnitine hydrolase, carnitine dehydrogenase and diaphorase in sequence, was developed for the sensitive and selective determination of urinary free and individual acylcarnitines by a reversed-phase high-performance liquid chromatography. A 100-microliter urine sample was directly injected onto the TSKgel ODS 80Ts column and eluted by a step-gradient procedure. The eluent was mixed with the substrate solution of beta-NAD+ (1.0 mmol/l), resazurin (25 mumol/l) and Tris acetate (0.2 mol/l, pH 9.0). The mixture was passed through the immobilized enzyme reactor at 40 degrees C. Acylcarnitines were hydrolyzed and the converted to rezorufin which was measured by monitoring the fluorescence intensity at lambda EX = 560 nm and lambda EM = 580 nm. Free, acetyl-, glutaryl-, propionyl-, butyryl-, isobutyryl-, valeryl- and isovalerylcarnitine were determined within 55 min with detection limits (< 1 mumol/l) and within-run and day-to-day imprecision (C.V. < 6%). Free, acetyl- and isobutyrylcarnitine were found in normal urine. On the other hand, propionylcarnitine was detected in the urine of children with propionic aciduria and methylmalonic aciduria and multiple acylcarnitines were found in the urine of children with glutaric aciduria (type II).

Acetylcarnitine↗

[Clinical observations on bladder cancer--difference in clinical features with age].

Three hundred and ninety-four patients with transitional cell carcinoma of the bladder who initially visited Yokohama City University Hospital were reviewed according to age group. The patients were divided into four groups, group A (less than 49 years old), group B (from 50 to 64 years old), group C (from 65 to 79 years old) and group D (more than 80 years old). The clinical characteristics as follows were obtained by statistical analysis compared with these four groups. No statistical significance was obtained about frequency of macroscopic hematuria as chief complaint. However, the younger age groups (A and B) tended to visit hospital later after the first symptom of hematuria. The older age groups (C and D) had multiple and large tumor at the first cystoscopic examination. The older age groups (C and D) had high stage and high grade tumor at the first roentgenological examination and transurethral biopsy or resection. The 5-year recurrence free rate after transurethral resection of bladder tumor (TUR-BT) of the older age group (D group) was lower than that of the other groups. The 5-year survival rate of older age group was lower than that of the younger age group. However, no statistical significance between the age groups existed concerning high grade or high stage tumor and survival after total cystectomy. We clarified here that the clinical features of elderly patients who have bladder cancer were significantly different from those of younger patients. Otherwise the prognosis of patients who have high grade and/or high stage bladder cancer were demonstrated to be poor regardless of age.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

Pre- and postnatal stimulation of pulmonary surfactant protein D by in vivo dexamethasone treatment of rats.

Fetal (days 18 and 20 of gestation), neonatal (days 0, 2 and 4 of neonate) and adult rats were injected with dexamethasone (1 mg/kg) in vivo and 24 hours later the effect on the contents of surfactant protein D (SP-D) in the rat lungs were examined in comparison with surfactant protein A, disaturated phosphatidylcholine and phosphatidylglycerol. In vivo dexamethasone treatment resulted in significant increases of SP-D content as the other 3 components of surfactant in both fetuses and neonates, but not in adults. Responsiveness to glucocorticoid treatment on SP-D content was maximum on day 1 of neonate (2.7 times control value). The contents of surfactant components examined tend to respond better to steroid in postnatal rats. These data demonstrated that glucocorticoid treatment in vivo for short durations exhibits the stimulatory effect on the contents of SP-D in the fetal and neonatal rat lungs.

Aging↗

[The effect of superoxide dismutase on the inflammation induced by periodontal pathogenic bacteria and wound healing of gingival incision].

The therapeutic effect of superoxide dismutase (SOD) and the role of O2- were assessed on 3 groups of Wistar rats (total 115). Fifty-four received injections of gingival bacteria or of anaerobically cultured rat dental plaque in their peritoneum, then received both intravenous (i.v.) and intraperitoneal (i.p.) injection of SOD. The rats were killed 48 hours later to collect their peritoneal exudate for cell count and for acid phosphatase activity assessment. Twenty-six received injections of bacteria in their footpads, after which SOD was administered intravenously. These rats were killed at 6 hours, 48 hours and 1 week respectively for histological examination. The gingiva of 26 rats were incised to create artificial lesions. The rats were killed at 24 or 48 hours and examined histologically. The nine remaining rats were used as controls (untreated) for the 3 experiments. The results of the 3 experiments showed that: Injection of SOD reduced exudation and acid phosphatase activity enhanced by the injection of B. gingivalis, at dosages of 1, 5 mg/kg i.p. and 5 mg/kg i.v., but 10 mg/kg i.p. had no apparent effect; i.v. injection of SOD had inhibitory effects on cell infiltration of B. gingivalis into the footpad, and the increase in fibrin and fibroblast formation through time was greater in SOD-administered rats; a decreased cell infiltration rate and increased fibrin network, fibroblast proliferation and gingival tissue regeneration occurred in specimens with artificial lesions given SOD. Apparently SOD has a curative effect on both inflammatory reaction induced by B. gingivalis and periodontal wound healing.

Acid Phosphatase↗

[Clinicopathological analysis of leiomyosarcomas of the small intestine and a review of the Japanese literature].

An analysis has been made of 9 cases of a leiomyosarcoma of the small intestine that were treated from 1974 through 1989. In two patients (22.2%), a perforation was seen, and a case report of a 59-year-old woman is presented. Further, case reports of leiomyosarcomas in the Japanese literature from 1980 through 1989 were clinico-pathologically analyzed. The frequency of a perforation was found to be 8.6%, and the distribution of the perforated leiomyosarcomas was the same as for the non-perforated cases. The five-year postoperative survival rate was 41.2%. Of note is that 3 out of 10 patients that had survived for 5 years subsequently died of sarcomatosis.

Adult↗

Fluorometric determination of carnitine in serum with immobilized carnitine dehydrogenase and diaphorase.

A fluorometric flow-injection method for determining carnitine with use of immobilized enzymes carnitine dehydrogenase (EC 1.1.1.108) and diaphorase (EC 1.8.1.4) was developed and applied to the assay of carnitine in serum of patients treated with valproic acid. After fractionation and hydrolysis of carnitines in serum samples by perchloric acid and potassium hydroxide, liberated carnitine was converted to resorufin by immobilized carnitine dehydrogenase and diaphorase in the presence of beta-NAD+ (1.0 mmol/L), resazurin (12.5 mumol/L), and Tris acetate (0.6 mol/L, pH 9.0) at 37 degrees C. The fluorescence intensity of resorufin was monitored at lambda Ex 560 nm and lambda Em 580 nm. The calibration curve was linear for carnitine amounts from 0.1 to 1.0 nmol. Quantitative analytical recovery and satisfactory within- and between-run imprecision of carnitine in each carnitine fraction were obtained. Interference by bilirubin, serum albumin, and hemoglobin was negligible. Carnitine deficiencies were detected in about 20% of the valproic acid-treated patients (n = 198). The present method should be useful for monitoring carnitine deficiencies in clinical laboratories.

Alcohol Oxidoreductases↗

[Expression of myc family oncogenes in primary human testicular cancer].

In order to understand the role of myc family genes (c-myc, N-myc and L-myc) in the development and progression of human testicular cancer, we have analyzed the expression of myc family genes in three different types of primary human testicular cancer (seminoma, embryonal carcinoma and teratocarcinoma) and normal testis using Northern blot analysis. Expression of N-myc gene, which is usually limited in the neoplasms derived from neuroectoderm, was detected in seven out of ten cases of seminomas and two out of two cases of embryonal carcinomas. Gene amplification was not observed in these cases. Expression of N-myc gene was not detected in teratocarcinomas and normal testes. Expression of c-myc gene was observed in seminomas, embryonal carcinomas, teratocarcinomas and normal testes, but specific expression of c-myc gene was not seen in these cancers and normal testes. Expression of L-myc gene was not detected in all cases examined in our studies. Since N-myc gene expression was observed only in undifferentiated testicular neoplasm, such as seminoma and embryonal carcinoma, its expression may be positively related to the development and progression of special types of human testicular cancer.

Blotting, Northern↗