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Biomedical subjects

H Murata

Publications and source records attributed to H Murata.

At least 145 records · Page 8Linked to original sources
PubMed1997

Helicobacter pylori and gastric carcinogenesis.

This article consists of three independent studies regarding Helicobacter pylori-related gastric carcinogenesis. Ammonia, a Helicobacter product, promoted chemically induced gastric carcinogenesis in animals. Moreover, an extract of Helicobacter stimulated inflammatory production of nitric oxide (NO), a potent mutagen that causes G:C-->A:T transition. Meta-analysis of recent studies demonstrated that G:C-->A:T transition is one of the most common mutations in the p53 tumor suppressor gene in early phases of human gastric carcinogenesis. Therefore, bacterial factors such as ammonia and host factors, including inflammatory NO production, might play important roles in H. pylori-induced gastric carcinogenesis.

Ammonia↗
PubMed1997

TGF-beta3 stimulates and regulates collagen synthesis through TGF-beta1-dependent and independent mechanisms.

In contrast to the TGF-beta1 and beta2 isoforms, TGF-beta3 has shown the ability to downregulate scarring and fibrosis in vivo under certain experimental conditions. In this study, we determined the direct effects of TGF-beta3 on cultures of human dermal fibroblasts. TGF-beta3 (0.1 to 100 pg per ml) increased DNA synthesis up to 50% (p < 0.01, r = 0.970), collagen protein synthesis up to 200% (dose range of 0.1 to 5 ng per ml, p < 0.001, r = 0.990), and increased alpha1(I) procollagen mRNA levels (r = 0.999), with maximal effects (200% of control) observed by 24 h. Collagen lattice contraction was increased by more than 50% in response to TGF-beta3 (p < 0.001), and to a similar extent as the TGF-beta1 isoform. Stimulation of collagen synthesis and of alpha1(I) procollagen mRNA levels in response to TGF-beta3 was partially blocked by a TGF-beta1-specific anti-sense oligonucleotide but was still detectable (35% greater than baseline) when TGF-beta3 was added to dermal fibroblasts from TGF-beta1 knock-out mice. In contrast with these stimulatory effects, however, downregulation of alpha1(I) procollagen, alpha1(III) procollagen, and TGF-beta1 mRNA levels toward baseline occurred when TGF-beta3 (0.1 to 5 ng per ml) was added simultaneously and in combination with TGF-beta1. We conclude that stimulation of collagen synthesis by TGF-beta3 occurs through TGF-beta1-dependent and independent pathways. By downregulating the response to TGF-beta1 and by shifting from one pathway to the other, TGF-beta3 can dampen and provide fine-tuning to the overall TGF-beta's induced program of collagen deposition.

Animals↗
PubMed1997

Epstein-Barr virus infection, Hodgkin's disease, non-Hodgkin's lymphoma, and reactive follicular hyperplasia in Japanese children: evaluation of paraffin-embedded specimens using polymerase chain reaction and immunohistochemistry.

Epstein-Barr virus (EBV) infections are common in Japanese children, with infectious by EBV type 1. The relationships between EBV infection and lymphadenopathies in Hodgkin's disease (HD), non-Hodgkin's lymphomas (NHL), reactive follicular hyperplasia (RFH), and infectious mononucleosis (IM) in 37 Japanese children were evaluated. Formalin-fixed, paraffin-embedded lymph node specimens that were obtained at surgical resection or biopsy were evaluated for the presence of EBV DNA and the latent membrane protein-1 (LMP-1) using polymerase chain reaction (PCR) and immunohistochemical staining. The PCR detected EBV DNA in nine of 13 (69.2%) patients with RFH, including a case of IM, all three (100%) patients with HD, and one of 21 (4.8%) patients with NHL. All EBV-positive samples contained EBV type 1. Reed-Sternberg's cells in HD were immunohistochemically positive for LMP-1, whereas all cases of RFH and NHL were negative for LMP-1. Results suggest that EBV infection may be related to HD. Although no proof exists that EBV infection contributes to the transformation of cells, thus causing RFH or NHL, the present authors suggest that the EBV-positive cases in Japanese children demonstrate a relationship between the clinical and histopathological features of the lymphadenopathy and EBV-type 1 infection.

Child↗
PubMed1997

Durometer measurements of skin induration in venous disease.

BACKGROUND: The degree of skin induration (lipodermatosclerosis) around venous ulcers has prognostic significance; however, objective measurements are needed to assess the induration. The durometer, an engineering instrument used to measure the hardness of metals and plastic, has recently been adapted to assess skin induration. OBJECTIVE: The purpose of this study was to measure skin induration and its relationship to skin ulceration by the use of a durometer, and to determine the influence of edema, if any, on durometer measurements. METHODS: The degree of skin induration on the medial leg was determined in six sequential, nonselected patients with lipodermatosclerosis and leg ulcers, and in five normal volunteers by using a blinded observer's clinical score (0 = normal to 3 = maximal induration) and a hand-held Type 0 durometer. In addition, durometer readings in 14 patients with edema and eight control subjects were taken on the tibia, the dorsum of the foot, and behind the ankle. RESULTS: Durometer readings in patients with leg ulcers and lipodermatosclerosis diminished as one measured from the superior edge of the ulcer to the knee (r = 0.925). The higher the clinical skin score the higher were the durometer readings (P = 0.0062). The presence of edema did not influence durometer measurements. CONCLUSION: The durometer is an effective and reliable instrument for measuring the degree of skin induration in venous ulceration and its readings are not affected by edema. Ulcers occur in skin most affected by lipodermatosclerosis.

Dermatology↗
PubMed1997

Constituents of a fern, Diplazium subsinuatum. II. Structure elucidation of five new hopane-triterpene glycosides.

From whole fern, Diplazium subsinuatum (Wall. ex Hook. et Grev.) Tagawa, two new hopane-triterpene glycosides named diplaziosides III and IV were isolated, together with three new hopane glycosides with acetylated sugars. The structures of diplaziosides III and IV were established as (22S)-24-O-alpha-L-arabinofuranosyl-(1 --> 2)- [beta-D-glucopyranosyl-(1 --> 6)]-beta-D-glucopyranosyl-20 alpha-O-beta-D-glucopyranosyl-30-hydroxyhopan-28-oic acid (1) and (22R)-24-O-alpha-L-arabinofuranosyl-(1-->2)-[beta-D-glucopyranosyl-(1--> 6)]-beta-D-glucopyranosyl-30-carboxy-17-hydroxy-hopano-28,22-lacto ne (2), respectively, on the basis of spectral evidence. Diplazioside III (1) is novel not only in its glycoside structure, but also in its triterpene structure and moreover, 1 provides the first instance of a naturally occurring bisdesmoside with a hopane aglycone. The structures (3a, 3b, and 4a) of the acetylated glycosides were also elucidated, and this is the first report of naturally occurring acetates of hopane glycosides.

Carbohydrate Sequence↗
PubMed1997

Augmented chemiluminescence response of bronchoalveolar lavage cells in calves receiving repeated daily sprayings of ammonia mist into the nasal cavities.

The effect of ammonia inhalation on the luminol-dependent chemiluminescence response of bronchoalveolar lavage (BAL) cells was investigated in clinically normal calves receiving eight ml of ammonia water (5,000 ppm) in the form of aerosol sprayed into the nasal cavities (four ml into each nostril) once a day for two weeks. The chemiluminescence level of BAL cells was augmented following the sprayings of ammonia compared with prior to exposure. The level still remained high one week after the exposure was removed, but showed recovery after two weeks.

Administration, Inhalation↗
PubMed1997

Measurement of the expiratory ammonia concentration and its clinical significance.

Although gaseous ammonia (NH3) can freely enter cells through the plasma membrane where NH3 is cyto(neuro)toxic, NH3 and ionic ammonia (NH4+) contents have not been studied in biological materials. We developed a new method for measurement of expiratory NH3 concentration, which may reflect blood NH3 concentrations. The method is a sensor tube type-gas assay system. Expiratory NH3 concentration in patients with chronic liver diseases increased when their blood ammonia (NH4(+)+NH3) concentrations increased above 90 micrograms/dl (normal range; 12-66 micrograms/dl). However, cirrhotic patients, who had relatively higher expiratory NH3 concentration compared to blood NH3 concentrations (calculated from Henderson-Hasselbalch formula), were found to have subclinical encephalopathy. Measurement of expiratory NH3 concentration may be of clinical significance for the diagnosis of encephalopathy associated with hyperammonemia.

Ammonia↗
PubMed1997

Metyrapone reductase purified partially from liver microsomes of male rats: the enzyme differs from acetohexamide reductase.

An enzyme catalyzing the reduction of metyrapone, a diagnostic drug with a ketone group, was partially purified from liver microsomes of male rats. The partially purified metyrapone reductase had no ability to reduce acetohexamide, an oral antidiabetic drug with a ketone group, even though both metyrapone and acetohexamide are reduced in liver microsomes of male rats. These results clearly indicate that the reduction of these two drugs can be catalyzed by different enzymes. The partially purified metyrapone reductase was found to reduce aldehydes, ketones and menadione. The substrate specificities were in fair agreement with those of carbonyl reductase. However, the partially purified enzyme was strongly inhibited by inhibitors of aldehyde reductase, such as barbital, phenobarbital and sodium valproate.

Acetohexamide↗
PubMed1997

[Reproducibility of regional cerebral blood flow measurement at rest with autoradiography method using 123I-IMP and SPECT].

Reproducibility of regional cerebral blood flow (rCBF) values obtained by the autoradiography (ARG) method with one SPECT scan and one point arterial blood sampling at 10 min after 123I-N-isopropyl-p-iodoamphetamine (IMP) infusion was evaluated. The variation in the cross calibration factor between SPECT counts and well-type scintillation counts remained 2.2% for 13 months. The error in rCBF by sampling time difference was less than 3% when sampling time was within 10 min +/- 30 sec after infusion. There was a favorable correlation between the rCBF values in two separate resting scans measured by the ARG method in 10 patients (r = 0.907). And the mean ratio of rCBF values by the second study to those by the first study in the cerebellum and cerebral lobes in 10 patients was 0.989 +/- 0.056 (mean +/- SD). There was no significant difference in rCBF values between two separate studies. Reproducibility of rCBF with the ARG method was proved to be good. The ARG method was thought to be useful for the assessment of treatment effects and clinical courses.

Aged↗
PubMed1997

[Coronary artery bypass grafting in patients aged 80 years or older].

Coronary artery bypass grafting (CABG) in elderly patients was increasing in recent years. Between January 1989, and December 1996, 11 patients aged 80 years or older (mean 81) underwent CABG in our hospital. Nine patients (82%) were in New York Heart Association class III or IV. Emergency surgery was required in 4 patients (36%). Incidence of emergency surgery is higher than younger patients (p < 0.005), emergency surgery required 7.7% (46/592) in younger patients. The operative mortality was 27% for these 80 years or older. It was one in elective cases and two of four (50%) in emergency cases. One operative death in elective cases was concomitant operation with arch aneurysm. More patients of CABG operations in octogenarians required emergency surgery, and emergency surgery is high operative mortality. Thus CABG in octogenarians should be performed earlier, not be denied because of age alone.

Age Factors↗
PubMed1997

Comparison of regional myocardial technetium-99m-MIBI uptake between ECG-gated and ungated SPECT imaging.

UNLABELLED: Technetium-99m-MIBI uptake was compared between ECG-gated and ungated SPECT images in 10 normal subjects and 10 patients with coronary artery disease to investigate the effects of wall motion on regional myocardial uptake. METHODS: Left ventricular ejection fraction (LVEF) and wall motion were evaluated using the first-pass data acquired immediately after injection of 1110 MBq 99mTc-MIBI. A transaxial ungated image was reconstructed with cumulative data during a cardiac cycle. For transaxial gated images, data during a cardiac cycle were divided into eight frames and the first seven frames were used. The lateral/septal ratios for ungated and gated images were obtained using the counts in the ROIs drawn in the lateral and the septal walls. RESULTS: In 10 normal subjects, the lateral/septal ratio for gated increased during end-systole. The mean of the lateral/septal ratio was significantly lower for ungated than for gated (1.025 vs. 1.077, p < 0.05). In patients with septal wall asynergy and a normokinetic lateral wall, the mean of the lateral/septal ratios was significantly lower for ungated than for gated (1.267 vs. 1.325, p < 0.01). CONCLUSION: Ungated SPECT acquisition may underestimate regional myocardial uptake when myocardial wall motion is good, therefore, ECG-gated data should be acquired for accurate assessment of regional myocardial uptake of 99mTc-MIBI.

Adult↗
PubMed1997

[Usefulness and limitations of 99mTc-MIBI scintigraphy for detection of parathyroid lesions].

To evaluate the usefulness of MIBI scintigraphy (MIBI) for parathyroid lesions, the detectability of lesions by MIBI was compared with that by Tl-Tc subtraction imaging, ultrasonography, CT and MRI in 56 histologically proved lesions. In neck lesions, ultrasonography (92%) and MIBI (85%) showed better detectability than those by the other three modalities. With MIBI, detectability was decreased for smaller parathyroid lesions that coexisted with thyroid disease. Among the five modalities, MIBI showed the highest detectability (88%) for ectopic or metastatic lesions. The smallest parathyroid lesions detected by MIBI were a parathyroid adenoma weighing 220mg and a parathyroid hyperplasia weighing 200mg. MIBI was thought to be more valuable for ectopic or metastatic parathyroid lesions.

Adenoma↗
PubMed1997

[Typical normal cases and normal cases with abnormal image pattern in every myocardial SPECT radiopharmaceutical].

Working group of cardiac nuclear medicine was made as a Japanese part of society of international cardiac nuclear medicine under the cooperation between Japanese society of nuclear medicine and Japanese society of cardiology. We investigated typical normal cases and normal cases with abnormal image pattern in every myocardial SPECT radiopharmaceutical as one of the research activity of working group. From 11 faculties, 16 T1 cases, 14 BMIPP cases, 8 MIBG cases, 8 MIBI cases and 14 tetrofosmin cases were submitted as typical normal cases, and 12 T1 cases, 5 BMIPP cases, 12 MIBG cases, 10 MIBI cases and 5 tetrofosmin cases were submitted as normal cases with abnormal image pattern. We summarized the condition of SPECT data acquisition of each faculties. And we added the discussion from literature about how to discriminate normal cases with abnormal image pattern from abnormal cases. In MIBG, patterns of typical normal cases and normal cases with abnormal image pattern were slightly different from other 4 pharmaceuticals. In other 4 pharmaceuticals, diaphragmatic attenuation, breast attenuation, apical thinning and others were presented as normal cases with abnormal image pattern.

3-Iodobenzylguanidine↗
PubMed1997

[An analysis of factors associated with the increase of in-patient medical expenditures for the elderly in Fukuoka Prefecture].

In order to evaluate factors associated with the increase in the in-patient medical expenditures for the elderly in Fukuoka prefecture during the period from 1987 to 1991, an analysis was conducted based on the data of 10 Health Care Regions. According to the results, there were two patterns in the increase. The first was the pattern observed in the southern part of the prefecture, where most of the increase in the in-patient medical expenditures for the elderly was explained by the increase of medical expenditures per capita. Furthermore, this increase per capita was due to the increase in utilization rate. This pattern is considered to be associated with the increase of general hospital beds as well as with the increase of the dependent elderly in the regions. The second pattern was observed in urban regions, such as Fukuoka and Kitakyushu, where the increase of in-patient medical expenditures for the elderly was mainly due to the increase in the number of elderly in the regions. This pattern is considered to be associated with the increase in the population categorized as the aged household. The present result suggests that in order to control the medical expenditures for the elderly, different service-mix strategies will be necessary, respecting the socio-economic characteristics of each region.

Demography↗
PubMed1996

Cloning of a cDNA encoding the human transforming growth factor-beta type II receptor: heterogeneity of the mRNA.

We have isolated two novel cDNAs encoding the transforming growth factor-beta (TGF-beta) type II receptor (TGF-beta IIR), termed TGF-beta IIR alpha and TGF-beta IIR beta 1 from a human fetal liver library. They have unique nucleotide (nt) sequences, compared with the reported TGF-beta IIR sequence, at the 5' end. Southern blot analysis using probes from each clone detected the specific genomic DNA fragments. RT-PCR analysis revealed a distinct pattern of expression for each isoform. These results indicated that TGF-beta IIR has heterogeneity in the structure, and the expression of TGF-beta IIR isoforms is differentially regulated. The heterogeneity of TGF-beta IIR molecules could be derived from alternative splicing and might elicit specific TGF-beta receptor functions.

Amino Acid Sequence↗
PubMed1996

Effects of age on levels of cysteine, glutathione and related enzyme activities in livers of mice and rats and an attempt to replenish hepatic glutathione level of mouse with cysteine derivatives.

There was a large statistically significant decrease in the hepatic level of cysteine and glutathione (GSH) in 24 month-old mice compared to young mice, while, cystine and glutathione disulfide (GSSG) contents in the liver did not differ between young and old mice. Activities of cystathionine gamma-lyase and beta-synthase in mouse liver of the 24 month-old group were significantly decreased. In rats, the hepatic levels of cysteine, cystine, GSH and GSSG exhibited no statistically significant change during aging to 30 month. As the rats matured, total hepatic activities of both cystathionine gamma-lyase and beta-synthase increased with maximum levels at 24 months of age and decreased to the same level found in 5 week old for the former and to 22% of that in 5 week old for the latter. Intraperitoneal administration of diethyl maleate to mice led to depletion of hepatic GSH. When N-acetylcysteine and a thiazolidine derivative were intravenously injected after diethyl maleate administration, the hepatic GSH level of mice was restored to the normal level.

Acetylcysteine↗
PubMed1996

[Analysis of financial statements of Japanese private hospitals (1982-1991)].

In order to clarify the financial situation of Japanese private hospitals, the financial statements provided by the Social Welfare and Medical Service Corporation were analyzed for the period from 1982 to 1991. The results clarified the low growth rate and low profitability of the Japanese private hospitals, although their financial situation was relatively stable. However, the efficiency of cost has been stalled in recent years and profitability has been declining due to the low turnover rate of capital. According to the CVP analysis, the Profit volume ratio of the investigated hospitals has been increased to the level of 95%. This situation means that, in the current financial situation, more than half of the Japanese private hospitals will go into the red if revenue declines 5% due to some short term change in the managerial environment.

Cost-Benefit Analysis↗