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Biomedical subjects

J Goto

Publications and source records attributed to J Goto.

At least 109 records · Page 6Linked to original sources
PubMed1995

Flow cytometric analysis of DNA synthetic phase fraction of the normal appearing colonic mucosa in patients with colorectal neoplasms.

DNA synthetic (S) phase fractions of normal appearing colonic mucosa in Japanese and British patients with colorectal neoplasms were compared with those in patients without colonic neoplasms. Normal crypts were isolated from fresh surgical specimens of the large intestine by the use of EDTA. After fixation with 70% ethanol, isolated crypts were digested with pepsin into single nuclei suspensions. These were stained with propidium iodide and examined by flow cytometry. S phase fraction was calculated from the flow cytometry DNA histogram using Baisch's method. S phase fractions of normal appearing crypts in Japanese and British patients with colorectal tumours were not significantly different and analysed together. S phase fraction of normal appearing colonic crypts in 14 patients with familial adenomatous polyposis (FAP) was 10.23 (2.59%) (mean SD)) ranging from 5.8 to 18.8. S phase fraction of background normal mucosal in patients with large adenomas (over 2 cm) and adenocarcinomas were 9.74 (3.76%) (range, 2.7-16.1) and 8.93 (3.54%) (range, 2.9-18.9) respectively. In normal mucosa of patients without any colorectal neoplasms, S phase fraction was 8.99 (3.94)% (range, 3.9-17.7). There was no statistically significant difference in S phase fractions of normal mucosa in the four groups. Our results show that an increase in proliferative activity of background colonic crypts is not necessary for tumour development.

Adenocarcinoma↗
PubMed1995

Analysis of triplet repeats in the huntingtin gene in Japanese families affected with Huntington's disease.

Huntington's disease (HD) is associated with the expansion of a CAG repeat in the huntingtin gene. Molecular analysis of the repeat in Japanese HD patients and normal controls was performed. The size of the CAG repeat ranged from 37 to 95 repeats in affected subjects and from seven to 29 in normal controls. A significant correlation was found between the age of onset and the CAG expansion. The length of the expanded repeat is unstable in meiotic transmission and large increases occur in paternal transmission. At the same time the CCG repeat polymorphism adjacent to the CAG repeat was analysed and haplotypes of HD chromosomes were identified. Strong linkage disequilibrium was found between the CAG repeat expansion and an allele of (CCG)10 in Japanese HD chromosomes. It is distinct from that described previously in western populations. Western HD chromosomes strongly associate with an allele of (CCG)7. Possible mechanisms underlying the disequilibrium in Japan are discussed.

Age of Onset↗
PubMed1995

Stereoisomeric inversion of (25R)- and (25S)-3 alpha,7 alpha,12 alpha-trihydroxy-5 beta-cholestanoic acids in rat liver peroxisome.

The stereoisomeric inversion of (25R)- and (25S)-3 alpha,7 alpha,12 alpha-trihydroxy-5 beta-cholestanoic acid (THCA) in rat liver peroxisome was studied. After incubation of an isomer of THCA-CoA thioester with a peroxisomal fraction, 5 beta-cholestanoic acids were extracted and optical antipodes were separated and determined by LC/APCI-MS. The transformation of (24E)-3alpha,7 alpha,12 alpha-trihydroxy-5 beta-cholest-24-en-26-oic acid (delta 24-THCA) formed by acyl-CoA oxidase was also analyzed by GC/NICI-MS. Rapid enzymatic epimerization from either direction was observed prior to biotransformation into (24E)-delta 24-THCA.

Animals↗
PubMed1995

Stereospecific dehydrogenation of (25R)- and (25S)-3 alpha,7 alpha,12 alpha-trihydroxy-5 beta-cholestanoic acids by acyl-CoA oxidase in rat liver light mitochondrial fraction.

From a stereochemical point of view, the dehydrogenation mechanism of the biotransformation of 3 alpha,7 alpha,12 alpha-trihydroxy-5 beta-cholestanoic acid (THCA) into (24E)-3 alpha,7 alpha,12 alpha-trihydroxy-5 beta-cholest-24-enoic acid (delta 24-THCA) has been studied with capillary gas chromatography (GC)/negative ion chemical ionization (NICI)-mass spectrometry. After incubation of (24R,25R)- or (24S,25S)-[24,25-2H2]THCA, synthesized from (24E)-delta 24-THCA by a deuterated diimide reduction, with a rat liver light mitochondrial fraction, 5 beta-cholestanoic acids were extracted and derivatized into a pentafluorobenzyl (PFB) ester-dimethylethylsilyl (DMES) ether. Subsequent resolution into THCA and delta 24-THCA was attained by GC on a cross-linked 5% phenylmethyl silicone fused-silica capillary column monitored with a corresponding characteristic carboxylate anion [M-PFB]- in the NICI mode. The stereospecific elimination of a pro-R hydrogen at C-24 in both (25R)- and (25S)-THCA indicated syn-elimination for the former, whereas anti-elimination for the latter was observed.

Acyl-CoA Oxidase↗
PubMed1995

Potential bile acid metabolites. 23. Syntheses of 3-glucosides of nonamidated and glycine- and taurine-amidated bile acids.

The 3-glucosides of nonamidated lithocholic, chenodeoxycholic, ursodeoxycholic, deoxycholic, and cholic acids, and their double conjugate forms with glycine and taurine were synthesized. The key reactions used were 1) beta-D- glucosidation at C-3 by the Koenigs-Knorr condensation reaction of 3 alpha-hydroxylated bile acid methyl (or p-nitrophenyl) esters with 1 alpha-bromo-1-deoxy-2, 3, 4, 6-tetra-O-acetyl-D-glucopyranose in the presence of cadmium carbonate in refluxing benzene; 2) indirect and direct amidations at C-24 by the activated p-nitrophenyl ester and by the diethylphosphorylcyanide methods, respectively, using glycinate ester and taurine as coupling agents; and 3) simultaneous alkaline hydrolysis of the hydroxyl-protecting and ester groups in both the sugar and aglycone moieties.

Amides↗
PubMed1995

[Molecular genetics of Huntington's disease].

Huntington's disease (HD) is a progressive neurodegenerative disorder which is clinically characterized by chorea, cognitive decline, and emotional disturbance; it is inherited in an autosomal dominant manner. The HD gene maps to chromosome 4p16.3. Our linkage analysis demonstrated a significant genetic linkage between Japanese HD families and the flanking markers, D4S127, D4S43. The molecular basis of the disease is an expansion of CAG repeat in the huntingtin gene. We performed molecular analysis of the repeat in Japanese HD patients and normal controls. The size of the CAG repeat ranged from 37 to 95 repeats in affected subjects and from seven to 29 in normal controls. A significant correlation was found between the age of onset and the CAG expansion. The length of the expanded repeat is unstable in meiotic transmission and large increases occur in paternal transmission. At the same time the CCG repeat polymorphism adjacent to the CAG repeat was analysed and haplotypes of HD chromosomes were identified. Striking linkage disequilibrium was found between the CAG repeat expansion and an allele of (CCG)10 in Japanese HD chromosome. It is distinct from that described previously in western populations. Western HD chromosomes strongly associate with an allele of (CCG)7.

Age of Onset↗
PubMed1994

Identification and characterization of dehydrocholic acid reductase system in the cytosol of human red blood cells.

We conducted in vivo and in vitro studies of the reductive metabolism of the cholagogue, dehydrocholic acid (DHCA). Immediately after the intravenous administration of 1 g of DHCA in normal subjects (n = 6), the concentration of the reductive metabolite, 3 alpha-hydroxy-7,12-dioxo-cholanoic acid (unconjugated form), increased sharply in the systemic circulation, rising to 95.8 microM 10 min after administration. The results of in vitro experiments with DHCA and whole blood showed that 3 alpha-hydroxy-7,12-dioxocholanoic acid were produced from DHCA. In vitro experiments using DHCA and the red blood cell fraction, and DHCA and the red blood cell cytoplasmic fraction gave similar results to those described above with whole blood. However, a reductive metabolite was not formed by the incubation of DHCA and the red blood cell membrane fraction. These findings indicated that, contrary to the conventional theory that intravenously administered DHCA is subjected to reductive metabolism only in the liver, reduction also occurs in the systemic circulation, and the mechanism for this reductive metabolism is present in the cytoplasmic fraction of red blood cells. Further investigation to characterize this reductive metabolic system revealed an optimum temperature of 37 degrees C, an optimum pH of 7.4, a Km value of 2.0 x 10(-3) M, and inactivation by heat treatment (70 degrees C for 2 min).

Bile Acids and Salts↗
PubMed1994

Identification of flanking markers for the familial amyotrophic lateral sclerosis gene ALS1 on chromosome 21.

Amyotrophic lateral sclerosis (ALS) is a progressive, adult-onset, neurodegenerative disorder characterized by the death of large motor neurons from the cerebral cortex, brainstem, and spinal cord. The etiology of ALS remains unknown; however, approximately 10% of the cases are familial in nature. In the majority of these families, the mode of transmission is autosomal dominant. Recently, linkage of an autosomal dominant familial ALS (FALS) gene to the locus ALS1 on chromosome 21q was established. In addition, evidence was provided for genetic heterogeneity, with approximately 55% of families most likely linked to chromosome 21. The development of a number of highly informative simple sequence repeat polymorphisms in the region of linkage-21q21 through 21q22.1-has permitted us to confirm both the assignment of ALS1 to 21q and the genetic heterogeneity of FALS. In addition, we have been able to refine the mapping of ALS1, based on recombination events in two of the linked families. Flanking markers for the FALS gene are D21S213 on the centromeric side and D21S219 on the telomeric side. The candidate region is approximately 4 Mb and contains the genes copper/zinc superoxide dismutase (CuZnSOD); the fourth member of the class II cytokine receptor family (CRF2-4); and the interferon-alpha receptor (IFNAR).

Amyotrophic Lateral Sclerosis↗
PubMed1994

Novel immunoaffinity extraction for liquid chromatographic determination of major metabolites of 4-acetoxy-2-(4-methylphenyl)benzothiazole in plasma.

Group extraction of the metabolites of 4-acetoxy-2-(4-methylphenyl)benzothiazole has been achieved through the use of an immunoaffinity adsorbent. The antisera elicited from an immunogen, 4-hydroxy-2-(4-formylphenyl)benzothiazole O-carboxymethyloxime-bovine serum albumin conjugate, were characterized to have a broad affinity spectrum for major metabolites oxidized at the 4-methyl group of the benzene moiety. One millilitre of the immunoaffinity adsorbent prepared by immobilization of antibodies (12.5 mg ml-1) was capable of retaining up to 4 micrograms of benzothiazoles. The adsorbates were recovered quantitatively by elution with 90% (v/v) methanol without any interfering peaks on the high-performance liquid chromatogram. The peak-height ratio of each metabolite to an internal standard was plotted against the concentration of the former substance; good linearity was observed in the range of 10-500 ng ml-1.

Animals↗
PubMed1994

Application of the crypt-isolation technique to flow-cytometric analysis of DNA content in colorectal neoplasms.

BACKGROUND/AIMS: Conventional flow-cytometric analysis of colorectal tumor DNA content includes both tumor and stromal cell DNA. To improve the method, we evaluated the DNA content of purified epithelial cells using the crypt-isolation technique. METHODS: Normal and neoplastic crypts were isolated from fresh resected colorectum nonenzymatically. Isolated crypts were digested into single nuclei suspensions and examined by flow cytometry (FCM). Internal controls from normal crypts were used to define diploidy. The neoplastic nuclei in the same individual and mixtures of both normal and neoplastic nuclei in various ratios were analyzed. RESULTS: Tumors having both diploid and aneuploid stemlines were found more frequently than that reported using conventional FCM. Near-diploid DNA stemlines with DNA indices ranging between 0.90 and 1.10 were detectable. The cases of advanced cancer in which the DNA index was between 0.90 and 0.95 were associated significantly with Dukes' stage C. CONCLUSIONS: This is the first reported analysis of the DNA content of "pure" neoplastic colorectal epithelia using FCM. Multiploid and near-diploid stemlines were more accurately analyzed than that using conventional FCM.

Adenocarcinoma↗
PubMed1994

DNA haplotype analysis of Huntington disease reveals clues to the origins and mechanisms of CAG expansion and reasons for geographic variations of prevalence.

This study of allelic association using three intra- and two extragenic markers within 150 kb of the Huntington disease (HD) mutation has provided evidence for linkage disequilibrium for four of five markers. Haplotype analysis of 67 HD families using markers in strong linkage disequilibrium with HD identified two haplotypes underlying 77.6% of HD chromosomes. Normal chromosomes with these two haplotypes had a mean number of CAG repeats significantly larger than and an altered distribution of CAG repeats compared with other normal chromosomes. Furthermore, haplotype analysis of five new mutation families reveals that HD has arisen on these same two chromosomal haplotypes. These findings suggest that HD arises more frequently on chromosomes with specific DNA haplotypes and higher CAG repeat lengths. We then studied CAG and CCG repeat lengths in the HD gene on 896 control chromosomes from different ancestries to determine whether the markedly reduced frequency of HD in Finland, Japan, China and African Blacks is associated with an altered frequency of DNA haplotypes and subsequently lower CAG lengths on control chromosomes compared to populations of Western European descent. The results show a highly significant inverse relationship between CAG and CCG repeat lengths. In populations with lowered prevalence rates of HD, CAG repeat lengths are smaller and the distribution of CCG alleles is markedly different from Western European populations. These findings suggest that, in addition to European emigration, new mutations make a contribution to geographical variation of prevalence rates and is consistent with a multistep model of HD developing from normal chromosomes with higher CAG repeat lengths.

Africa↗
PubMed1994

Immunoaffinity extraction of 4-hydroxy-2-(4-methylphenyl)benzothiazole and its metabolites for determination by gas chromatography-mass spectrometry.

Immunoaffinity extraction of 4-hydroxy-2-(4-methylphenyl)benzothiazole and its metabolites, together with the corresponding meta-isomers has been achieved by the use of an antibody raised against an immunogen, an O-carboxymethyloxime-bovine serum albumin conjugate of 4-hydroxy-2-(4-formylphenyl)benzothiazole. The antibody produced exhibited a broad spectrum of affinity, not only for metabolites oxidized at the 4-methyl group of the benzene moiety but also for the corresponding meta-isomers. Up to 4 micrograms in total of these benzothiazoles could be extracted on the immunoaffinity adsorbent and recovered almost quantitatively by elution with 90% methanol. The resulting chromatogram was free from any interference. The eluted compounds were derivatized by conversion to their methyl esters and/or trimethylsilyl ethers, and subsequently separated into individual benzothiazoles by means of gas chromatography-mass spectrometry. The derivatized compounds were monitored using a characteristic ion, [M-CH3]+., and the limit of detection was 10 fmole. The peak height ratio of each metabolite to its corresponding meta-isomer internal standard was plotted against the concentration of the former and good linearity was observed over the range 0.2-5 ng/ml.

Anti-Inflammatory Agents, Non-Steroidal↗
PubMed1994

Analysis of conjugated bile acids in human biological fluids. Synthesis of hyodeoxycholic acid 3- and 6-glycosides and related compounds.

The glucuronide, glucoside and N-acetylglucosaminide conjugates of hyodeoxycholic acid were synthesized. In addition, murideoxycholic acid 3-glycosides and some of their C-5 epimeric analogs were also prepared. The principal reactions used are 1) the Koenigs-Knorr condensation reaction of 3-oxo-6 alpha-hydroxy and 6-oxo-3 alpha-hydroxy esters with an appropriate alpha-acetohalosugar catalyzed by cadmium carbonate in benzene under reflux, 2) reduction of the resulting bile acid glycoside methyl ester-acetates with tert-butylamine-borane complex, and 3) subsequent hydrolysis with aqueous lithium hydroxide.

Bile Acids and Salts↗
PubMed1994

Synthesis and evaluation of novel thiazolidine derivatives as thromboxane A2 receptor antagonists.

A series of 3-benzoyl or 3-phenylsulfonyl-2-substituted thiazolidine derivatives were synthesized, and evaluated for their thromboxane A2 (TXA2) receptor-antagonizing effect on (15S)-15-hydroxy-11 alpha,9 alpha-(epoxymethano)prosta-5(Z),13(E)-dienoic acid (U-46619)-induced aggregation of rabbit platelet-rich plasma (PRP). A simple 2-aryl-thiazolidine derivative, 3-benzoyl-2-(4-hydroxy-3-methoxyphenyl)thiazolidine (5a), showed mild TXA2 receptor antagonist activity. Modification of 5a led to 2-chloro-4-[3-(4-chlorophenylsulfonyl)thiazolidin-2-ylmet hyl]phenoxyacetic acid (29d), which showed 10 times more potent TXA2 receptor antagonist activity than 5a.

Animals↗
PubMed1994

Cross-sectional and longitudinal studies on the effect of water exercise in controlling bone loss in Japanese postmenopausal women.

The effects of water exercise, as a form of daily physical activity (water exercise in a warm water pool), on bone loss in healthy Japanese postmenopausal women have been cross-sectionally and longitudinally investigated from the viewpoint of preventing osteoporosis. In the cross-sectional study, the bone mineral density (BMD) of the lumbar spine (Z-score (%)) in the Veterans group (N = 27), who had been exercising for 35.2 months on average, was significantly higher than that in the Newcomers (N = 40), who had only begun to exercise 3 or 4 weeks before, and that in the Non-exercisers (N = 30), serving as a control group. The rate of change in the BMD of the lumbar spine was -0.92%/year in the Non-exercisers (N = 30), +1.55%/year in the Veterans (N = 20), and +2.16%/year in the Newcomers (N = 15), based on BMD Z-scores. In the Exercisers groups, it was found that the rate of change in the BMD showed a slight increase rather than a decrease irrespective of the duration of menopause. On the other hand, in the Non-exercisers group, the rate of change in the BMD decreased slightly. The results of questionnaires showed that the subjects' general awareness of health and fitness in daily life was enhanced after starting the water exercise program. These results suggest that consistently participating in water exercise is an important factor in preventing bone loss, and moreover, appears not only to indirectly improve awareness of daily physical activity but also to promote health and improve daily life.

Aged↗
PubMed1994

[Gas chromatography/mass spectrometry analysis of steroid hormones].

Gas chromatography/mass spectrometry (GC/MS) has been used as a sensitive and specific tool for the determination of steroid hormones. The instruments made great progress in the advent of chemically inert fused silica capillary columns and various sample injection systems. Characteristics of electron impact and chemical ionization methods, and of the derivatization reagent are described. The sensitive method by GC in combination with negative ion chemical ionization MS is also outlined. Solid phase extraction by an octadecylsilyl bonded silica cartridge and an immobilized antibody column as well as chromatographic separation by lipophilic ion-exchange gel for the clean-up of steroid hormones in biological fluids are discussed in this article.

Gas Chromatography-Mass Spectrometry↗
PubMed1994

[Clinical analysis of benign tumors of the lung].

Benign tumors of the lung occur in low frequency, but its differential diagnosis from malignant tumors such as lung cancer is important. This paper presents as analysis of clinical features of 26 cases operated on for benign tumor of the lung. Histologically there were 15 hamartomas, 8 sclerosing hemangiomas, 2 inflammatory pseudotumors and one clear cell tumor. The roentgenographic appearances were well defined circumscribed solitary nodules in 17 cases (65%), and lobulation and spiculation in 9. Histological diagnosis of benign tumors was not obtained in all cases preoperatively. Minimal resection procedures were performed in 22 cases (85%). No postoperative complications developed.

Adolescent↗