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K Higashi

Publications and source records attributed to K Higashi.

At least 37 records · Page 2Linked to original sources

Technique for removing a bent intramedullary femoral nail: a case report.

The authors present a case in which an interlocked intramedullary nail placed to secure a left femoral shaft fracture was deformed twelve months after surgery because of secondary trauma. The nail was straightened by sectioning through half of its diameter with a drill for metal under minimal soft tissue dissection, then removed and replaced with another nail. The femur subsequently healed without complications.

Accidents, Traffic↗

An inwardly rectifying K(+) channel, Kir4.1, expressed in astrocytes surrounds synapses and blood vessels in brain.

Glial cells express inwardly rectifying K(+) (Kir) channels, which play a critical role in the buffering of extracellular K(+). Kir4.1 is the only Kir channel so far shown to be expressed in brain glial cells. We examined the distribution of Kir4.1 in rat brain with a specific antibody. The Kir4.1 immunostaining distributed broadly but not diffusely in the brain. It was strong in some regions such as the glomerular layer of the olfactory bulb, the Bergmann glia in the cerebellum, the ependyma, and pia mater, while little activity was detected in white matter of the corpus callosum or cerebellar peduncle. In the olfactory bulb, Kir4.1 immunoreactivity was detected in a scattered manner in about one-half of the glial fibrillary acidic protein-positive astrocytes. Immunoelectron microscopic examination revealed that Kir4.1 channels were enriched on the processes of astrocytes wrapping synapses and blood vessels. These data suggest that Kir4.1 is expressed in a limited population of brain astrocytes and may play a specific role in the glial K(+)-buffering action.

Animals↗

Effects of soy protein on levels of remnant-like particles cholesterol and vitamin E in healthy men.

We determined the effects of soy protein isolate (SPI) intake on remnant-like particles (RLP), lipolytic enzymes, lipid transfer protein, transaminases, sex hormones, iron, calcium, and vitamin E in healthy men. In the first randomized, crossover experiment, 14 men were given either 20 g per day of SPI or nothing (control) for each 4-week segment. After 3 weeks of SPI intake, TG and RLP cholesterol levels were significantly lower than the baseline by 13.4% (p<0.05) and 9.8% (p<0.05), respectively. However, no significant change was found in total and low-density lipoprotein (LDL) cholesterol levels or the activities of lipoprotein lipase, hepatic lipase, cholesteryl ester transfer protein, and lecithin cholesterol acyltransferase. Although the levels of transaminases. testosterone, iron, and calcium did not change, the vitamin E level was reduced from the baseline by 9.7%, a significant decrease (p<0.01). In the second study, we attempted to determine the effect of vitamin E supplement taken with SPI. For each 3-week segment, 12 men were given 20 g per day of SPI, either with or without 200 mg per day of vitamin E, in a randomized crossover design. The vitamin E level was reduced by 9.2%, a significant decrease (p<0.05), after SPI intake for 3 weeks, and vitamin E supplement increased vitamin E level significantly (p<0.05). These results demonstrate that SPI intake reduces remnant lipoproteins, TG, and the plasma level of vitamin E, although vitamin E supplementation compensates for the reduction of vitamin E. Therefore the supplementation of vitamin E may be required in subjects with long-term and abundant intake of soy protein.

Adult↗

[Conference of morphological analysis].

To date, hematological malignancies have been diagnosed and classified by morphological analysis following ordinary and special staining such as Wright's and Giemsa's double staining. The FAB classification, which is applied for acute leukemia, is a typical classification system used worldwide. Recently, various reference techniques have been developed for the diagnosis of hematological malignancies and are useful for diagnosing hematological diseases, but morphological analysis still remains the basic reference technique. Therefore, expertise in morphological analysis is extremely important, and full training in this field is necessary.

Aged↗

Angiotensin-converting enzyme inhibitors and probucol suppress the time-dependent increase in urinary Type IV collagen excretion of Type II diabetes mellitus patients with early diabetic nephropathy.

BACKGROUND: A multicenter prospective clinical trial was carried out in 9 National Hospitals in Japan to elucidate the time-dependent change in urinary Type IV collagen excretion rate of Type II diabetes mellitus (DM) patients, and to investigate whether an angiotensin-converting enzyme inhibitor (ACE-I) or probucol is effective in preventing progression of renal involvement of diabetics by evaluating urinary Type IV collagen excretion. METHODS: Normo- and microalbuminuric patients with Type II DM were recruited. Patients were assigned to either the control (n = 88), ACE-I (n = 43) or probucol (n = 37) group and treated for 24 months. Besides albumin excretion rate (AER), urinary Type IV collagen excretion rate was also measured. RESULTS: Although, AER, urinary N-acetyl-beta-D-glucosaminidase and beta2-microglobulin excretion rates in the control group did not vary over 24 months, urinary Type IV collagen excretion rate in the control group increased time-dependently (p < 0.01 vs baseline at 18 months and p < 0.005 vs baseline at 24 months). In the ACE-I and probucol groups, time-dependent increases in urinary Type IV collagen excretion rates were not observed. In the ACE-I group, the urinary Type IV collagen excretion rate was significantly lower than that in the control group at 24 months (p < 0.05). In the probucol group, the urinary Type IV collagen excretion rate was significantly lower than that in the control group at 6 months (p < 0.05). In the ACE-I group, AER decreased significantly compared with baseline at 18 months (p < 0.05) and at 24 months (p < 0.005). CONCLUSIONS: ACE-I has a beneficial effect and probucol may have a beneficial effect in preventing the progression of early diabetic nephropathy. Measurement of the urinary Type IV collagen excretion rate in combination with AER would be useful for the management of early renal involvement in Type II DM.

Acetylglucosaminidase↗

Expression of multidrug resistance protein and messenger RNA correlate with (99m)Tc-MIBI imaging in patients with lung cancer.

UNLABELLED: In vitro studies have shown that (99m)Tc-sestamibi (MIBI) is a transport substrate for the P-glycoprotein (Pgp) pump and the multidrug resistance-associated protein (MRP) pump. However, whether MRP and lung resistance protein (LRP) affect tumor accumulation and efflux of (99m)Tc-MIBI in lung cancer is not known. In this study, we explored whether Pgp and the other pumps, MRP and LRP, affect tumor accumulation and efflux of (99m)Tc-MIBI in lung cancer. METHODS: Thirty-four lung cancer patients who underwent surgery were examined. Before surgery, (99m)Tc-MIBI SPECT was performed 15 min and 180 min after injection, and early uptake, delayed uptake (L/Nd), and washout rate (L/Nwr) of (99m)Tc-MIBI were obtained. Pgp, MRP, and LRP expression were investigated by immunohistochemistry. The messenger RNA (mRNA) level of Pgp, MRP, and LRP was determined by real-time reverse-transcription polymerase chain reaction. The lung cancer (99m)Tc-MIBI images were correlated with protein and mRNA expression. RESULTS: The mean L/Nd of the Pgp (-) group was significantly higher than that of the Pgp (++) group (P = 0.0324). The Pgp (++) group had a higher L/Nwr than did the Pgp (-) group (P = 0.0269). The mean L/Nd of the Pgp mRNA low-expression group was significantly higher than that of the Pgp mRNA high-expression group (P = 0.0127). The Pgp mRNA high-expression group had a higher L/Nwr than did the Pgp mRNA low-expression group (P = 0.0825). No appreciable correlation was found between the lung cancer (99m)Tc-MIBI images and the expression of MRP or LRP on the level of protein or mRNA. CONCLUSION: These data suggest that an increased level of Pgp expression correlates with a low accumulation on delayed scans and a high L/Nwr of (99m)Tc-MIBI in lung cancer. Neither MRP nor LRP expression on the level of either protein or mRNA correlated significantly with tumor accumulation or efflux of (99m)Tc-MIBI in lung cancer.

ATP Binding Cassette Transporter, Subfamily B, Mem↗

Comparison of [(18)F]FDG PET and (201)Tl SPECT in evaluation of pulmonary nodules.

UNLABELLED: Recent reports have indicated the value of [(18)F]FDG PET and (201)Tl SPECT in diagnosing lung cancer. In this study, we compared the diagnostic value of FDG PET and (201)Tl SPECT in the evaluation of pulmonary nodules. METHODS: Sixty-three patients with 66 pulmonary nodules suspected to be lung cancer on the basis of chest CT were examined by FDG PET and (201)Tl SPECT (early and delayed scans) within a week of each study. For semiquantitative analysis, the standardized uptake value (SUV) or the tumor-to-nontumor activity ratio (T/N) (or both) was calculated. All of these lesions were completely removed thoracoscopically or by thoracotomy and were examined histologically. RESULTS: Fifty-four nodules were histologically confirmed to be malignant tumors, and 12 were benign. Both techniques delineated focal lesions with an increase in tracer accumulation in 41 of 54 lung cancers. (201)Tl SPECT on early or delayed scans (or both) identified 4 additional lung cancers that FDG PET images did not reveal: 3 bronchioloalveolar carcinomas and a well-differentiated adenocarcinoma. FDG PET identified 3 additional lung cancers that (201)Tl SPECT images did not reveal; 2 of these lung cancers were <2 cm in diameter. The mean FDG SUV and T/N of bronchioloalveolar carcinomas (2.06 +/- 0.76 and 3.49 +/- 1.03, respectively) were significantly lower than those of poorly differentiated adenocarcinomas (5.55 +/- 2.01 [P = 0.026] and 8.23 +/- 2.16 [P = 0.01], respectively). However, no significant difference was found in (201)Tl T/N on early and delayed scans between bronchioloalveolar carcinomas (1.64 +/- 0.29 and 1.87 +/- 0.42, respectively) and poorly differentiated adenocarcinomas (1.58 +/- 0.32 and 2.76 +/- 1.36, respectively). Of the 12 benign nodules, FDG PET and (201)Tl SPECT showed false-positive results for the same 7 benign nodules (58.3%) (4 granulomas, 1 sarcoidosis, 1 inflammatory pseudotumor, and 1 aspergilloma). Negative FDG PET findings and positive (201)Tl SPECT findings were obtained only for bronchioloalveolar carcinomas or a well-differentiated adenocarcinoma but not for other histologic types of lung cancers or benign pulmonary nodules. CONCLUSION: No significant difference was found between FDG PET and (201)Tl SPECT in specificity for the differentiation of malignant and benign pulmonary nodules. The degree of differentiation of lung adenocarcinoma correlated with FDG uptake but not with (201)Tl uptake. Bronchioloalveolar carcinoma (a well-differentiated, slow-growing tumor) findings typically were positive with (201)Tl but were negative with FDG. The combination of FDG PET and (201)Tl SPECT may provide additional information regarding the tissue characterization of pulmonary nodules.

Adenocarcinoma↗

[Current situation and future for cytometry--leukocyte function].

There are granulocytes, monocytes and lymphocytes in the leukocyte of the peripheral blood. These leukocytes play an important part to each other for biophylaxis by forming the network. Therefore, it is important inspection to measure the number of these leukocytes and function. Recently, various reference techniques in flow cytometry have been developed for the leukocyte function. It is introduced phagocytosis for granulocyte, cytoplasmic free Calcium localization in granulocytes, lymphocyte transformation and cytoplasmic pH in lymphocytes.

Calcium↗

Cadmium-induced mRNA expression of Hsp32 is augmented in metallothionein-I and -II knock-out mice.

Cadmium is toxic and carcinogenic to humans and animals. The testis and lung are the target organs for cadmium carcinogenesis. Heat shock proteins (HSPs) as well as metallothionein (MT) and glutathione (GSH) play an important role in protection against its toxicity. HSP32, also known as heme oxygenase-1, is a 32-kDa protein induced by heme, heavy metals, oxidative stresses, and heat. We investigated expression of the Hsp32 gene of various organs (the liver, lung, heart, stomach, kidney, and testis) in transgenic mice deficient in the MT-I and -II genes (MT-KO) and in control mice (MT-W) after an injection of cadmium chloride (CdCl2). Survival of MT-W mice after a subcutaneously injection of CdCl2 was higher than that of MT-KO mice, while no significant difference was observed in the level of GSH in each organ between MT-W and MT-KO mice. Northern blot analysis showed that the MT-I mRNA was more extensively induced in the liver, kidney, and heart than other organs 6 h after an injection of CdCl2 (30 micromol/kg body wt, sc). There was little increase of the MT-I mRNA in the testis when induced by CdCl2. Expression of the Hsp32 gene in the liver and kidney in response to CdCl2 was more extensively augmented in MT-KO mice than in MT-W mice. In the lung and testis, there was little induction and no augmentation in expression of the Hsp32 gene induced by CdCl2 in both MT-W and MT-KO mice. In the stomach, there was little induction of the Hsp32 mRNA in MT-W mice, but was increased in MT-KO mice. Immunohistochemical staining revealed that the HSP32 protein was strongly expressed in the kidney and liver of MT-W mice 24 h after an injection of CdCl2 (20 micromol/kg body wt, sc), while the expression of HSP32 protein was not increased in the testis. In metabolically active organs such as the liver and kidney, expression of the Hsp32 gene as well as the MT-I gene was extensively induced by cadmium in MT-W mice, and more eminently induced in MT-KO mice. We suggest that organs of low stress response to cadmium such as the testis and lung may be vulnerable target sites for cadmium toxicity and carcinogenesis.

Animals↗

Investigation of possible involvement of several genes related to development of hepatocarcinogenesis in rats.

A comparative study on the possible involvement of several genes in the susceptibility of chemical carcinogenesis was carried out using carcinogen-resistant DRH rat and -sensitive Donryu and F344 rats. Previously, we observed that the induction of glutathione S-transferase placental form (GST-P) in the liver of Donryu rats by 3'-methyl-4-dimethylaminoazobenzene (3'-Me-DAB) was significantly greater than that of DRH rats. In the present study, we tentatively determined base sequences of the enhancer region including GPE-I and GPE-II (GST-P enhancers I and II) of GST-P genes of DRH, Donryu and F344 rats, but we did not observe any nucleotide polymorphism around these regions. Furthermore, the mRNA levels of silencer binding protein (NFA-1) for the GST-P promoter of rat liver were also similar in the DRH and Donryu rats. Since clonal expansion of putative preneoplastic GST-P-positive foci in the DRH rat liver was significantly suppressed during 3'-Me-DAB administration, we examined whether two opposite growth controlling factors, TGF-alpha and TGF-beta, may participate in such suppression of growth. It was supposed that mannose 6-phosphate/insulin-like growth factor 2 receptor (M6P/IGF2R), at least in part, activates TGF-beta preproprotein. However, we observed that the levels of M6P/IGF2R mRNA in the livers of DRH were not higher than those of Donryu rats after being fed 3'-Me-DAB for 8 weeks. Another important factor in the carcinogenesis is insulin-like growth factor II itself. Although liver tumors induced by 3'-Me-DAB in F344 had high levels of IGF-II mRNA, little IGF-II gene expression existed in normal adult livers of Donryu, F344 and DRH rats. High levels of IGF-II mRNA were detected similarly in the livers of neonates from all these three strains of rats. Finally, we detected a significant increase of AFP (alpha-fetoprotein) mRNA in the livers of Donryu rats around 6 to 8 weeks from the start of 3'-Me-DAB feeding, which is in parallel with detrimental effects of this carcinogen on these rats. A reduced induction of AFP mRNA was observed in DRH rats under the same conditions. Further study will be needed to explain the lower tumor susceptibility in the DRH rat.

Animals↗

Genetic resistance to chemical carcinogen-induced preneoplastic hepatic lesions in DRH strain rats.

DRH strain rats were established by inbreeding a closed colony of Donryu rats continuously fed the chemical hepatocarcinogen 3'-methyl-4-dimethylaminoazobenzene for over 10 years. They are highly resistant to chemical induction of liver cancer and preneoplastic lesions. We studied the genetic basis of DRH resistance to preneoplastic lesions by analyzing 108 (F344 x DRH)F2 male rats fed 3'-methyl-4-dimethylaminoazobenzene for 7 weeks. Five parameters of preneoplastic liver lesions were selected for quantitative analysis: (a) number of glutathione S-transferase placental form-positive foci per unit area of liver section; (b) percentage area occupied by the foci; (c) average size of foci; (d) glutathione S-transferase placental form mRNA level; and (e) gamma-glutamyltranspeptidase mRNA level. Furthermore, O6-methylguanine DNA methyltransferase and mannose 6-phosphatase/insulin-like growth factor 2 receptor mRNA levels were quantified. Composite interval mapping analysis showed that there were two remarkably significant clusters of quantitative trait loci affecting preneoplastic liver lesions on chromosomes 1 and 4. These clusters were designated collectively as Drh1 and Drh2, respectively. The functions of the recessive DRH allele of Drh1 and the semidominant DRH allele of Drh2 were to suppress the phenotypes of precancerous lesions. Each cluster showed two to three subpeaks in linkage likelihood plots, suggesting the presence of several closely linked quantitative trait loci affecting preneoplastic lesions. Possible candidate genes at each locus will be discussed. Expression of O6-methylguanine DNA methyltransferase and mannose 6-phosphatase/insulin-like growth factor 2 receptor did not affect DRH resistance to hepatocarcinogenesis, although they were polymorphic between DRH and F344 rats.

Alleles↗

Purification from conditioned medium and chemical identification of a factor that inhibits somatic embryogenesis in carrot.

Somatic embryogenesis is strongly inhibited in cultures of carrot (Daucus carota L.) cells when the cell density is high. The inhibition is caused by factors that are released by cells into the medium of such cultures. In this study, we purified and identified one of the inhibitory factors found in the medium of high-cell-density cultures of carrot cells. The inhibitory factor with the strongest apparent activity was purified by fractionation with ethylacetate, chromatography on an octadecylsilyl (ODS) silica gel-column and HPLC. The inhibitory factor had a single peak of absorbance at 280 nm and was identified as 4-hydroxybenzyl alcohol by mass spectrometry and 1H- and 13C-NMR spectroscopy. Authentic 4-hydroxybenzyl alcohol strongly inhibited the formation of somatic embryos at a concentration equal to that in high-cell-density cultures. These results suggest that 4-hydroxybenzyl alcohol is a major factor that accumulates in high-cell-density cultures of carrot cells and inhibits somatic embryogenesis.

Benzyl Alcohols↗

FDG PET in the evaluation of the aggressiveness of pulmonary adenocarcinoma: correlation with histopathological features.

2-[Fluorine-18]fluoro-2-deoxy-d-glucose (FDG) uptake within the primary lesion correlates with survival on positron emission tomography (PET) studies of patients with non-small cell lung cancer. The more metabolically active the tumour, the worse the outcome. The aim of this study was to determine whether a correlation exists between aggressiveness as determined by pathology and the findings of FDG PET in pulmonary adenocarcinoma. Thirty-five patients with 38 adenocarcinomas of the lung were studied. All patients underwent thoracotomy within 4 weeks of the FDG PET study. For semiquantitative analysis, standardized uptake values (SUVs) were calculated. Patients were classified into high SUV (> or = 4.0) and low SUV (<4.0) groups. The degree of FDG uptake (SUVs) in primary lung lesions was correlated with the histopathological features of aggressiveness (pleural involvement, vascular invasion or lymphatic permeation). The mean SUV of aggressive adenocarcinomas (4.36+/-1.94, n = 22) was higher than that of non-aggressive ones (1.53+/-0.88, n = 16) (P < 0.0001). Tumours with a high FDG uptake have a significantly higher likelihood of aggressiveness than those with a low FDG uptake (P = 0.0004). Analysis by the Kaplan-Meier methods revealed that the groups had different prognoses (log-rank test, P = 0.0099). The high SUV group had a significantly worse prognosis. In conclusion, a correlation was seen between aggressiveness as determined by pathology and glucose metabolism as measured by FDG PET in adenocarcinoma of the lung. FDG PET may be used as a non-invasive diagnostic technique in measuring aggressiveness and prognosis in patients with pulmonary adenocarcinoma.

Adenocarcinoma↗

Analyses of oxidative DNA damage and its repair activity in the livers of 3'-methyl-4-dimethylaminoazobenzene-treated rodents.

We measured the levels of 8-hydroxyguanine (8-OH-Gua) and its repair activity in the livers of the Donryu rat, the carcinogen-resistant DRH rat, and the ddy mouse, which were fed a 0.06% 3'-methyl-4-dimethylaminoazobenzene (3'-MeDAB)-containing diet. In a short-term rat experiment (maximum 2 months), 3'-MeDAB did not increase the 8-OH-Gua levels in the livers of the two rat strains, although it significantly increased the repair activity in only the Donryu rat liver at 1 and 2 months. After long-term 3'-MeDAB administration to the ddy mouse (8 months), the levels of 8-OH-Gua and its repair activity were increased in the liver by 3.6-fold and 1.6-fold, respectively. These experiments suggest that 3'-MeDAB increases 8-OH-Gua generation in rodent liver DNA and the 8-OH-Gua repair assay is a reliable marker of cellular oxidative stress induced by carcinogens.

Animals↗

Plasma levels and redox status of ascorbic acid and levels of lipid peroxidation products in active and passive smokers.

Both active and passive smoking are regarded as risk factors for various diseases. To clarify the effects of active and passive smoking on plasma vitamin C levels and lipid peroxidation status, we examined the plasma levels of ascorbic acid (AA), its redox status [ratio of dehydroascorbate (DHAA) to total AA], the levels of thiobarbiturate reactive substance (TBARS), and the levels of lipid peroxides (LPO) in smokers, nonsmokers, and nonsmokers regularly exposed to environmental cigarette smoke (passive smokers). The study population consisted of 149 healthy males: 75 active smokers (consumption of > 15 cigarettes/day for more than 5 years), 36 passive smokers (more than 10 hr/week exposure to environmental cigarette smoke), and 38 nonsmokers (no cigarette smoke exposure). There were no significant differences in plasma TBARS and LPO levels among the three groups. Plasma levels of AA, the reduced form of vitamin C, were significantly lower in active smokers than in the combined nonsmoking groups (7.2 +/- 3.5 and 8.4 +/- 3.4 microg/mL, respectively; p < 0.05). Although no significant differences were found in plasma DHAA levels among the three groups, the ratios of DHAA to total AA were significantly higher in active and passive smokers than nonexposed nonsmokers (11.2, 10.3, and 7.1%, respectively; p < 0.05). These results indicate that passive smoking, as well as direct inhalation of cigarette smoke, affects the redox status of plasma AA. In passive smokers, the altered redox status of plasma AA suggests an oxidative stress.

Adult↗

Blunt cell growth potential in carcinogen resistant inbred DRH rats.

A carcinogen-resistant inbred strain DRH/Sea has been developed from the Crj:Donryu strain. The rats had a very low incidence of liver tumors when they were fed diets containing a hepatocarcinogen such as 3'-methyl-4-dimethylamino-azobenzene (3'-Me-DAB). Despite using 3'-Me-DAB during the stage of selection, the DRH/Sea rats developed normally, reproduced and did not have any spontaneous tumor in the lung, liver or uterus at over 1 year of age. Although their growth curves were similar to the Crj:Donryu rats, the progression of polyploidization in the liver was significantly delayed when compared with Crj:Donryu rats. Mitogenic changes that occurred in the liver caused by either 3'-Me-DAB or lead nitrate were less significant in the DRH rats than in Crj:Donryu rats. Furthermore, the growth rate of cultured fibroblasts derived from the DRH rats was slower than that of Crj:Donryu rats. These results, together with our previous results, suggest that slow growth potential is present under certain conditions in DRH rats. These findings may explain partly the meaning of the different susceptibility to hepatocarcinogens.

Animals↗

Effect of alcohol intake on the levels of plasma homocysteine in healthy males.

Hyperhomocysteinemia in chronic alcoholics has been reported, but it remains unclear whether relatively low alcohol intake compared with the previous reports affects the plasma homocysteine level. To investigate this issue, we performed two studies, a population-based study and an alcohol withdrawal study. An analysis of plasma homocysteine levels in a population of 236 healthy males showed no significant association between alcohol consumption and other tested parameters. In the withdrawal study, the subjects with a history of daily alcohol consumption (81.8 +/- 33.0 g/d, mean +/- SD, 40-150g/d, range) abstained from alcohol for 4 wk. After withdrawal, the levels of serum gamma-glutamyl transpeptidase, aspartate aminotransferase, triglycerides, and high-density lipoprotein cholesterol significantly decreased, but the plasma homocysteine level did not change. These results suggest that alcohol intake, at least as far as the amount of beverages our study subjects consumed, has no effect on the plasma homocysteine level in healthy males.

Adult↗