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71.
We examined serum copper (Cu), serum zinc (Zn), and the serum copper/zinc ratio (Cu/Zn) in 162 patients. All of them were seen to have an abnormal shadow in the chest X-ray films, that is, 109 patients with lung cancer (LC) and 53 patients with no lung cancer (NLC). The mean Cu and Cu/Zn in LC patients were significantly higher than those in NLC patients (p<0.05). In LC patients, Cu and Cu/Zn were higher and Zn was lower in advanced tumors than early ones. There was a significantly clear relation between Cu or Cu/Zn and the tumor (T) stages. When the relative risk (RR) of LC was estimated, it was seen that the higher Cu and Cu/Zn became, the higher RR became. Furthermore, we showed the sensitivity of the receiver operator characteristic of the test (ROC) curve for Cu, Cu/Zn, and carcinoembryonic antigen (CEA) to diagnose LC, as explained in a paragraph of methods.The determinations of Cu, Zn, and Cu/Zn are simple and inexpensive. They also appear to have a great diagnostic value in determining the local invasion of LC and as a screening test in the high-risk patients for LC.  相似文献   
72.
Supplement of 1% lithocholic acid (LCA) in the diet for 5-9 days resulted in elevated levels of the marker for liver damage aspartate aminotransferase and alkaline phosphatase activities in both farnesoid X receptor (FXR)-null and wild-type female mice. The levels were clearly higher in wild-type mice than in FXR-null mice, despite the diminished expression of a bile salt export pump in the latter. Consistent with liver toxicity marker activities, serum and liver levels of bile acids, particularly LCA and taurolithocholic acid, were clearly higher in wild-type mice than in FXR-null mice after 1% LCA supplement. Marked increases in hepatic sulfating activity for LCA (5.5-fold) and hydroxysteroid sulfotransferase (St) 2a (5.8-fold) were detected in liver of FXR-null mice. A 7.4-fold higher 3alpha-sulfated bile acid concentration was observed in bile of FXR-null mice fed an LCA diet compared with that of wild-type mice. Liver St2a content was inversely correlated with levels of alkaline phosphatase. In contrast, microsomal LCA 6beta-hydroxylation was not increased and was in fact lower in FXR-null mice compared in wild-type mice. Clear decreases in mRNA encoding sodium taurocholate cotransporting polypeptide, organic anion transporting polypeptide 1, and liver-specific organic anion transporter-1 function in bile acid import were detected in LCA-fed mice. These transporter levels are higher in FXR-null mice than wild-type mice after 1% LCA supplement. No obvious changes were detected in the Mrp2, Mrp3, and Mrp4 mRNAs. These results indicate hydroxysteroid sulfotransferase-mediated LCA sulfation as a major pathway for protection against LCA-induced liver damage. Furthermore, Northern blot analysis using FXR-null, pregnane X receptor-null, and FXR-pregnane X receptor double-null mice suggests a repressive role of these nuclear receptors on basal St2a expression.  相似文献   
73.
Summary The translation activity of mRNA coding for argininosuccinate synthetase in total RNA extracted from the liver of three patients with quantitative-type citrullinemia was determined using a cell-free translation system. In two patients, the hepatic content of the enzyme was about 20% of the control value, whereas translatable mRNA level for the enzyme was similar to or slightly lower than those of control livers. In the third patient, the enzyme content was about 50% of the control value, and mRNA activity for the enzyme was low normal. These results indicate that at least in the first two patients, the decrease in the enzyme protein is due either to increased degradation of the enzyme or to decreased translation in the patient's liver.  相似文献   
74.
The genes encoding the catalytic domains (CD) of the three endoglucanases (EG I; Cel7B, EG II; Cel5A, and EG III; Cel12A) from Trichoderma reesei QM9414 were expressed in Escherichia coli strains Rosetta-gami B (DE3) pLacI or Origami B (DE3) pLacI and were found to produce functional intracellular proteins. Protein production by the three endoglucanase transformants was evaluated as a function of growth temperature. Maximal productivity of EG I-CD at 15°C, EG II-CD at 20°C and EG III at 37°C resulted in yields of 6.9, 72, and 50 mg/l, respectively. The endoglucanases were purified using a simple purification method based on removing E. coli proteins by isoelectric point precipitation. Specific activity toward carboxymethyl cellulose was found to be 65, 49, and 15 U/mg for EG I-CD, EG II-CD, and EG III, respectively. EG II-CD was able to cleave 1,3–1,4-β-d-glucan and soluble cellulose derivatives. EG III was found to be active against cellulose, 1,3–1,4-β-d-glucan and xyloglucan, while EG I-CD was active against cellulose, 1,3–1,4-β-d-glucan, xyloglucan, xylan, and mannan.  相似文献   
75.
Heat shock protein 10 (hsp10) is a member of the molecular chaperones and works with hsp60 in mediating various protein folding reactions. GroES is a representative protein of hsp10 from Escherichia coli. Recently, we found that GroES formed a typical amyloid fibril from a guanidine hydrochloride (Gdn-HCl) unfolded state at neutral pH. Here, we report that other hsp10 homologues, such as human hsp10 (Hhsp10), rat mitochondrial hsp10 (Rhsp10), Gp31 from T4 phage, and hsp10 from the hyperthermophilic bacteria Thermotoga maritima, also form amyloid fibrils from an unfolded state. Interestingly, whereas GroES formed fibrils from either the Gdn-HCl unfolded state (at neutral pH) or the acidic unfolded state (at pH 2.0-3.0), Hhsp10, Rhsp10, and Gp31 formed fibrils from only the acidic unfolded state. Core peptide regions of these protein fibrils were determined by proteolysis treatment followed by a combination of Edman degradation and mass spectroscopy analyses of the protease-resistant peptides. The core peptides of GroES fibrils were identical for fibrils formed from the Gdn-HCl unfolded state and those formed from the acidic unfolded state. However, a peptide with a different sequence was isolated from fibrils of Hhsp10 and Rhsp10. With the use of synthesized peptides of the determined core regions, it was also confirmed that the identified regions were capable of fibril formation. These findings suggested that GroES homologues formed typical amyloid fibrils under acidic unfolding conditions but that the fibril core structures were different, perhaps owing to differences in local amino acid sequences.  相似文献   
76.
In the higher plant, Arabidopsis thaliana, histidine-to-aspartate (His-to-Asp) phosphorelay signal transduction systems play crucial roles in propagation of environmental stimuli, including plant hormones. This plant has 11 sensor His-kinases, 5 histidine-containing phosphotransfer (HPt) factors (AHPs), and 20 response regulators (ARRs). To gain new insight into the functions of these phosphorelay components, their intracellular localization was examined with use of GFP-fusion proteins, constructed for certain representatives of HPt factors (AHP2) and type-A and type-B ARRs (ARR6/ARR7 and ARR10, respectively). The results showed that AHP2 is mainly located in the cytoplasmic space, while both the types of ARRs have an ability to enter preferentially into the nuclei, if not exclusively. Together with the results from an in vitro phosphorelay assay with AHP2 and ARRs, these results are discussed, in terms of a geneal framework of the Arabidopsis His-to-Asp phosphorelay network.  相似文献   
77.
Host genetic factors may be important determinants of susceptibility to tuberculosis, and several candidate gene polymorphisms have been shown to date. A series of recent reports concerning rare human deficiencies in the type-1 cytokine pathway suggest that more subtle variants of relevant genes may also contribute to susceptibility to tuberculosis at the general population level. To investigate whether polymorphisms in the interleukin-12 receptor (IL-12R) gene predispose individuals to tuberculosis, we studied these genes by single-strand conformational polymorphism analysis and direct sequencing. Although no common polymorphisms could be identified in the IL-12R beta 2 gene ( IL-12RB2), we confirmed four single nucleotide polymorphisms (SNPs; 641A-->G, 684C-->T, 1094T-->C, and 1132G-->C) causing three missense variants (Q214R, M365T, G378R) and one synonymous substitution in the extracellular domain of the IL-12R beta 1 gene ( IL12RB1). All SNPs were in almost perfect linkage disequilibrium (D'=0.98), and two common haplotypes of IL12RB1(allele 1: Q214-M365-G378; allele 2: R214-T365-R378) were revealed. Polymerase chain reaction/restriction fragment length polymorphism and sequence analyses were used to type IL12RB1polymorphisms in 98 patients with tuberculosis and 197 healthy controls in Japanese populations. In our case-control association study of tuberculosis, the R214-T365-R378 allele (allele 2) was over-represented in patients with tuberculosis, and homozygosity for R214-T365-R378 (the 2/2 genotype) was significantly associated with tuberculosis (odds ratio: 2.45; 95% CI: 1.20-4.99; P=0.013). In healthy subjects, homozygotes for R214-T365-R378 had lower levels of IL-12-induced signaling, according to differences in cellular responses to IL-12 between two haplotypes. These data suggest that the R214-T365-R378 allele, i.e., variation in IL12RB1, contribute to tuberculosis susceptibility in the Japanese population. This genetic variation may predispose individuals to tuberculosis infection by diminishing receptor responsiveness to IL-12 and to IL-23, leading to partial dysfunction of interferon-gamma-mediated immunity.  相似文献   
78.
Journal of Industrial Microbiology & Biotechnology - Menaquinone is an obligatory component of the electron-transfer pathway in microorganisms. Its biosynthetic pathway was established by...  相似文献   
79.

Purpose

The purpose of this study was to verify whether the dynamic tumor tracking (DTT) feature of a Vero4DRT system performs with 10-mm-long and 0.28 mm diameter gold anchor markers.

Methods

Gold anchor markers with a length of 10 mm and a diameter of 0.28 mm were used. Gold anchor markers were injected with short and long types into bolus material. These markers were sandwiched by a Tough Water (TW) phantom in the bolus material. For the investigation of 4-dimensional (4D) modeling feasibility under various phantom thicknesses, the TW phantom was added at 2 cm intervals (in upper and lower each by 1 cm). A programmable respiratory motion table was used to simulate breathing-induced organ motion, with an amplitude of 30 mm and a breathing cycle of 3 s. X-ray imaging parameters of 80 kV and 125 kV (320 mA and 5 ms) were used. The least detection error of the fiducial marker was defined as the 4D-modeling limitation.

Results

The 4D modeling process was attempted using short and long marker types and its limitation with the short and long types was with phantom thicknesses of 6 and 10 cm at 80 kV and 125 kV, respectively. However, the loss in detectability of the gold anchor because of 4D-modeling errors was found to be approximately 6% (2/31) with a phantom thickness of 2 cm under 125 kV. 4D-modeling could be performed except under the described conditions.

Conclusions

This work showed that a 10-mm-long gold anchor marker in short and long types can be used with DTT for short water equivalent path length site, such as lung cancer patients, in the Vero4DRT system.  相似文献   
80.
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