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1.
In order to evaluate the importance of estrogen production in tumor and surrounding tissues, we measured mRNA expression levels of 5 enzymes participating to estrogen synthesis in situ and 4 breast cancer-related proteins in 27 pairs of tumor and non-malignant tissues. Steroid sulfatase (STS) mRNA was more frequently detected in tumor tissues rather than in their non-malignant counterparts. Estrogen sulfotransferase (EST) was constantly expressed with high level not only in tumor tissues but also in their surrounding non-malignant counterparts. In contrast, mRNA expression levels of aromatase, and 17β-hydroxysteroid dehydrogenase type I and II were relatively low and detected only in small proportion of the patients. We also measured the mRNA expression levels of the same nine genes in tumor tissues of 197 breast cancer patients, and analyzed relationship between the mRNA expression level and the clinicopathological parameters. The mRNA expression levels of STS, aromatase and erbB2 in tumor tissues increased as breast cancer progressed. The tumoral mRNA expression levels of STS, estrogen receptor β, and erbB2 in patients with recurrence were higher than those in patients without recurrence. Upregulation of STS expression plays an important role in tumor progression of human breast cancer and is considered to be responsible for estrogen production in tumor and surrounding tissues.  相似文献   
2.
The nucleotide sequences of the cloned human salivary and pancreatic α-amylase cDNAs correspond to the continuous mRNA sequences of 1768 and 1566 nucleotides, respectively. These include all of the amino acid coding regions. Salivary cDNA contains 200 bp in the 5′-noncoding region and 32 in the 3′-noncoding region. Pancreatic cDNA contains 3 and 27 bp of 5′- and 3′-noncoding regions, respectively. The nucleotide sequence humology of the two cDNAs is 96% in the coding region, and the predicted amino acid sequences are 94% homologous.Comparison of the sequences of human α-amylase cDNAs with those previously obtained for mouse α-amylase genes (Hagenbuchle et al., 1980; Schibler et al., 1982) showed the possibility of gene conversion between the two genes of human α-amylase.  相似文献   
3.
ABSTRACT

Previous studies have found that keeping the room dark at night was associated with a decrease in manic symptoms for patients with bipolar disorder (BD). However, the association between light at night of real-life conditions and manic symptoms is unclear. We investigated the association between bedroom light exposure at night and manic symptoms in BD patients. One-hundred and eighty-four outpatients with BD participated in this cross-sectional study. The average light intensity at night during sleep was evaluated using a portable photometer for seven consecutive nights. Manic symptoms were assessed using the Young Mania Rating Scale (YMRS), and scores ≥5 were treated as a “hypomanic state.” The median (interquartile range) YMRS score was 2.0 (0–5.0), and 52 (28.2%) participants were in a hypomanic state. The prevalence of a hypomanic state was significantly higher in the participants with an average light intensity at night exposure of ≥3 lux than in those with <3 lux (36.7% versus 21.9%; P = .02). In multivariable logistic regression analysis adjusted for BD type, depressive symptoms, sleep duration, and daytime physical activity, the odds ratio (OR) for a hypomanic state was significantly higher for the participants with an average light intensity at night exposure of ≥3 lux than for those with <3 lux (OR: 2.15, 95% confidence interval: 1.09–4.22, P = .02). This association remained significant at the cutoff value of YMRS score ≥6 (OR: 2.51, 95% confidence interval: 1.15–5.46; P = .02). The findings of this study indicate bedroom light exposure at night is significantly associated with manic symptoms in BD patients. Although the results of this cross-sectional investigation do not necessarily imply causality, they may serve to inform beneficial nonpharmacological intervention and personalized treatment of BD patients.  相似文献   
4.
The acute effects of insulin on glucose utilization in isolated rat quiescent cardiac myocytes were studied. Insulin (80 nM) increased the rate of glucose clearance by 2-3 times in the presence of glucose ranging from 0.3 microM to 5.5 mM. Glucose transport, which was measured in terms of both D-glucose uptake in the presence of 0.3 microM D-glucose and initial rate of uptake of 3-O-methylglucose, was stimulated 3-fold in the presence of insulin. At higher glucose concentrations (greater than 100 microM), a decrease in glucose clearance rate due to a shift of the rate-limiting step from glucose transport to a post-transport step in the pathway of glucose metabolism was observed. At the physiological concentration of glucose (5.5 mM), about 73% of glucose was metabolized into lactate, about 10% was oxidized into CO2 and the rest (17%) remained inside the cells. The pentose phosphate pathway did not contribute to the glucose metabolism in these cells. Insulin (80 nM) significantly increased the uptake of glucose (112%), and the conversions of glucose into lactate (16%), glycogen (64%), and triglyceride (18%), but not into CO2 (3%). Insulin transiently increased the percentage of I-form of glycogen synthase by 16% above basal, but did not affect the percentage of a-form of glycogen phosphorylase. The content of glucose 6-phosphate in the cells was increased by 46% above the basal value in the presence of insulin. These results indicate that insulin has different acute stimulatory effects on various steps in the metabolic pathway of glucose in isolated quiescent cardiac myocytes.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
5.
Streptococcus mutans strain AHT (serotype g) secretes at least two glucosyltransferases with different pI values. A novel glucosyltransferase with a pI of 5.8 was purified 244-fold from the ammonium sulphate fraction by DEAE-cellulose chromatography, FPLC (Mono Q column, Pharmacia) and hydrophobic chromatography. The enzyme preparation gave a single protein band on analysis by both PAGE and SDS-PAGE, and did not form multiple protein bands detectable by IEF. The Mr was estimated to be about 130,000 by SDS-PAGE and about 135,000 by ultracentrifugal analysis. The apparent Km value and pH optimum of the enzyme were 3.9 +/- 0.2 mM (mean +/- SD) and about 4.7, respectively. The enzyme synthesized water-soluble glucan from sucrose, and the glucan consisted of over 90 mol% 1,6-alpha-D-glucosidic linkages. The enzyme activity was not stimulated by primer dextran. Anti-enzyme serum produced a single precipitin band with the purified enzyme preparation, whereas it did not react with either of the other two known glucosyltransferases.  相似文献   
6.
Embryos were collected nonsurgically from n?turally-cycling or superovulated donors 7 d after estrus. Forty-four morulae, early blastocysts and blastocysts classified as good to excellent were bisected using a fine glass needle to produce forty-four identical demi-embryos. The bisected demi-embryos, without zonae pellucidae, were nonsurgically transferred, either by twin or single transfer. An additional forty-eight embryos were collected from the same donors and transferred as a control. Among the twin transfers, 8 of the 13 recipients became pregnant (61.5%). Seven of them conceived twin fetuses (87%) and one a single fetus. However, only two sets of normal identical twin calves were obtained. Among the single transfers, 72.6% (45/62) of bisected embryos without zonae pellucidae resulted in pregnancy, of which 48.4% (30/62) were identical twins, and 24.2% (15/62) were singletons. Another 27.4% (17/62) of the recipients did not became pregnant. The pregnancy rate for whole embryos with zonae pellucidae was 72.9% (35/48). These data show that there was no significant difference between the pregnancy rates of bisected embryos without zonae pellucidae and whole embryos with zonae pellucidae transferred 7 d after estrus. Bisection of bovine embryos was simplified and even morula stage embryos were transferred without zonae pellucidae.  相似文献   
7.
Summary The applications of immobilized lipase ofMucor miehei for the synthesis of acetone glycerol acyl ester from acetone glycerol and fatty acid, which is the first step for monoglyceride production was investigated. With a high oleic acid to acetone glycerol ratio (O/A, mol/mol), a high catalytic activity was observed under low water content in the reaction mixture. By the combination of high O/A ratio (>3) and removal of water which was produced during the reaction, the conversion degree was increased to almost 100%. With the O/A ratio of 3, the approximate half-life of the immobilized lipase and productivity of ester was estimated to be 20 days and 869 g product/g immobilized enzyme per 2 half-lives, respectively.  相似文献   
8.
9.
The direct cardiac action of 1-O-alkyl-2-acetyl-sn-glycero-3-phosphocholine (PAF) was studied in isolated perfused guinea-pig heart preparations. PAF produced a fall in left ventricular pressure, decreases in the rate of rise of the left ventricular pressure (dp/dt) and coronary flow, but had no effect on heart rate. These results indicate that PAF is a cardiodepressant with inotropic selectivity and this effect on heart is blocked by CV-3988, a specific PAF antagonist.  相似文献   
10.
A combined system of chemiluminescence detection and high performance liquid chromatography (CL–HPLC) was developed to determine primary peroxidation products in biological tissues, such as phosphatidylcholine hydroperoxide (PCOOH). The CL–HPLC assay consists of separation of lipid classes with HPLC and detection of hydroperoxide-specific chemiluminescence. Hydroperoxides react with heme compounds to produce oxidants as suggested by our early studies on tissue low-level chemiluminescence in which singlet molecular oxygen is generated as one of the excited species in several biological systems involving free radical events. In the CL–HPLC method, a cytochrome c–luminol mixture was used as a hydroperoxide-specific luminescent reagent, and the quantification of hydroperoxide was performed by detecting chemiluminescence due to the luminol oxidation caused by the oxidant produced during the lipid hydroperoxides with heme. The detection limit of PCOOH was 10 pmole hydroperoxide–O2. PCOOH in normal human blood was found to be 10–500 pmol/ml plasma and significantly higher levels of PCOOH were observed in some hospitalized patients.  相似文献   
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