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991.
Although notable progress has been made in the treatment of non-small-cell lung cancer (NSCLC) in recent years, this disease is still associated with a poor prognosis. Despite early-stage NSCLC is considered a potentially curable disease following complete resection, the majority of patients relapse and eventually die after surgery. Adjuvant chemotherapy prolongs survival, altough the absolute improvement in 5-year overall survival is only approximately 5%.Trying to understand the role of genes which could affect drug activity and response to treatment is a major challenge for establishing an individualised chemotherapy according to the specific genetic profile of each patient. Among genes involved in the DNA repair system, the excision repair cross-complementing 1 (ERCC1) is a useful markers of clinical resistance to platinum-based chemotherapy. In the International Lung Cancer Trial (IALT) adjuvant chemotherapy significantly prolonged survival among patients with ERCC1 negative tumors but not among ERCC1-positive patients. BRCA1 and ribonucleotide reductase M1 (RRM1), two other key enzymes in DNA synthesis and repair, appear to be modulators of drug sensitivity and may provide additional information for customizing adjuvant chemotherapy.Several clinical trials suggest that overexpression of class III β-tubulin is an adverse prognostic factor in cancer since it could be responsible for resistance to anti-tubulin agents. A retrospective analysis of NCIC JBR.10 trial showed that high tubulin III expression is associated with a higher risk of relapse following surgery alone but also with a higher probability of benefit from adjuvant cisplatin plus vinorelbine chemotherapy.Finally, the use of gene expression patterns such as the lung metagene model could provide a potential mechanism to refine the estimation of a patient’s risk of disease recurrence and could affect treatment decision in the management of early stage of NSCLC.In this review we will discuss the potential role of pharmacogenomic approaches to guide the medical treatment of early stage NSCLC.Key Words: NSCLC, adjuvant treatment, molecular markers, ERCC1, RRM1, β-tubulin, EGFR.  相似文献   
992.
The action of 10 and 20 mM Ca against harmful Cd effect on PS2 complex isolated from leaves of Phaseolus coccineus L. cv. Pi?kny Ja? was studied. The changes in fast chlorophyll a fluorescence induction kinetics and protein composition of PS2 complex were the symptoms of Cd toxicity and Ca protection of PS2 complex. Calcium applied at 10 mM concentration prevented F0 reduction caused by the presence of 250–1000 μM Cd in the incubation mixture, but that of (the variable chlorophyll a fluorescence) Fv, Fm, Fv/F0, and Fv/Fm only at 250 μM Cd. Ca concentration doubling in the incubation mixture resulted in complete overcoming the toxicity of 250–1000 μM Cd to Fv and Fm. However, the protection of Fv/F0 and the photochemical efficiency of PS2 (Fv/Fm) from 1000 μM Cd was only partial even at 20 mM Ca. A protective effect of 10 mM Ca on D1, D2 and 17 kDa proteins was found in PS2 complex exposed to 250 μM Cd, and on 43 kDa protein in the complex treated with 500 μM Cd. However, 20 mM Ca counteracted the toxicity of 500 μM Cd to the 43, 47 and 17 kDa proteins, as well as the harmful effect of 1000 μM Cd on 47 and 17 kDa ones.  相似文献   
993.
Epoxiconazole (CAS‐No. 133855‐98‐8) was recently shown to cause both a marked depletion of maternal estradiol blood levels and a significantly increased incidence of late fetal mortality when administered to pregnant rats throughout gestation (GD 7–18 or 21); estradiol supplementation prevented this epoxiconazole effect in rats (Stinchcombe et al., 2013), indicating that epoxiconazole‐mediated estradiol depletion is a critical key event for induction of late fetal resorptions in rats. For further elucidation of the mode of action, the placentas from these modified prenatal developmental toxicity experiments with 23 and 50 mg/kg bw/d epoxiconazole were subjected to a detailed histopathological examination. This revealed dose‐dependent placental degeneration characterized by cystic dilation of maternal sinuses in the labyrinth, leading to rupture of the interhemal membrane. Concomitant degeneration occurred in the trophospongium. Both placentas supporting live fetuses and late fetal resorptions were affected; the highest degree of severity was observed in placentas with late resorptions. Placental degeneration correlated with a severe decline in maternal serum estradiol concentration. Supplementation with 0.5 and 1.0 μg of the synthetic estrogen estradiol cyclopentylpropionate per day reduced the severity of the degeneration in placentas with live fetuses. The present study demonstrates that both the placental degeneration and the increased incidence of late fetal resorptions are due to decreased levels of estrogen, since estrogen supplementation ameliorates the former and abolishes the latter. Birth Defects Res (Part B) 98:208–221, 2013. © 2013 Wiley Periodicals, Inc.  相似文献   
994.
Camellia japonica L. (Theaceae, Theales) is an acidophilic evergreen flowering shrub and is traded worldwide. Symbiotic associations between the roots of this plant species and arbuscular mycorrhizal fungi (AMF), commonly recognized as natural biofertilizers and biocontrol agents, have been poorly studied so far. The aim of our study was to verify whether the application of nonspecific commercial AMF-based inocula could succeed and improve the growth of C. japonica. An experiment was conducted concerning the application of commercial inocula constituted by a specific AMF isolate (Funneliformis mosseae) or a consortium of different fungi and bacteria as alternatives to fertilization in pot cultivated C. japonica ‘Dr. Burnside’. Several growth parameters, plant nutrition and mycorrhization levels were monitored at the end of plant cultivation. Generally, increases in some macroelements (Ca, Mg, K) and microelements (Cu, Mn, Fe, Zn) were detected in the root system of inoculated camellias, while only Cu and Mn accumulation was increased in the leaves. Plants inoculated with the consortium inoculum exhibited increased chlorophyll content and foliage diameter while plants inoculated with F. mosseae exhibited increased number of flowers. Based on the polymorphism of an 18S rDNA region, we assessed the inoculated AMF that colonized C. japonica roots. The experiments showed that the applied AMF poorly colonized the root system of C. japonica. We suggest that commercial AMF formulations should be more targeted and host-specific in order to successfully colonize the host root and, potentially, fully express their benefits.  相似文献   
995.
The cyanidin-3- O - &#103 -glucopyranoside (C-3-G) antioxidant capacity towards reactive oxygen species (ROS)-mediated damages was assessed in tissue and cells submitted to increased oxidative stress. In the isolated ischemic and reperfused rat heart, 10 or 30 &#119 M C-3-G protected from both lipid peroxidation (66.7 and 94% inhibition of malondialdehyde (MDA) generation in 10 and 30 &#119 M C-3-G-reperfused hearts, respectively, in comparison with control reperfused hearts) and energy metabolism impairment (higher ATP concentration in 10 and 30 &#119 M C-3-G-reperfused hearts than in control reperfused hearts). These effects were associated to C-3-G permeation within myocardial cells, as indicated by results obtained in the isolated rat heart perfused for 30 min in the recirculating Langendorff mode under normoxia with 10 and 30 &#119 M C-3-G. Protective effects were exerted, in a dose-dependent manner, by C-3-G also in 2 mM hydrogen peroxide-treated human erythrocytes. With respect to MDA formation, an apparent IC 50 of 5.12 &#119 M was calculated for C-3-G (the polyphenol resveratrol used for comparison showed an apparent IC 50 of 38.43 &#119 M). The general indications are that C-3-G (largely diffused in dietary plants and fruits, such as pigmented oranges very common in the Mediterranean diet) represents a powerful natural antioxidant with beneficial effects in case of increased oxidative stress, and at pharmacological concentrations it is able to decrease tissue damages occurring in myocardial ischemia and reperfusion.  相似文献   
996.
ABSTRACT

A phytosociological study of the shrubland communities which colonise abandoned terraced olive groves in the Tyrrhenian district of Central Italy is presented here. The vegetational analysis was carried out using the Braun Blanquet phytosociological approach. Two main types of shrubland communities characterising distinct environmental conditions occur within abandoned terraced olive groves. On the one hand, there are those scrub types which tend to occupy the central part of the terrace; on the other hand, there are the scrubs types which develop along the stone walls bordering the terrace. Different phytosociological associations, sub-associations, and variants ranging from Pistacio-Rhamnetalia alaternii to Prunetalia spinosae are recognised and described. In the warm dry areas, both Myrto-Lentiscetum and Rhamno-Euphorbietum dendroidis occur. Also, a new Oleo-Ceratonion sub-association (Myrto-Lentiscetum spartietosum junceii) is presented here for the first time. In the inner zones of the study area, a range of aspects characterising a new Pruno-Rubion ulmifolii community type (Roso-Rubetum ulmifolii ass. nova) are identified.  相似文献   
997.
The nitrilases include a variety of enzymes with functional specificities of nitrilase, amidase, and hydrolase reactions. The crystal structure of the uncharacterized protein SA0302 from the pathogenic microorganism Staphylococcus aureus is solved at 1.7?Å resolution. The protein contains 261 amino acids and presents a four-layer αββα sandwich with a chain topology similar to that of a few known CN-hydrolase folds. In the crystal, the proteins are arranged as dimers whose monomers are related by a pseudo twofold rotation symmetry axis. Analysis of the sequences and structures of CN-hydrolases with known 3D structures shows that SA0302 definitely is a member of Branch 10 (Nit and NitFhit) of the nitrilase superfamily. Enzyme activities and substrate specificities of members of this branch are not yet characterized, in contrast to those of the members of Branches 1–9. Although the sequence identities between Branch 10 members are rather low, less than 30%, five conserved regions are common in this subfamily. Three of them contain functionally important catalytic residues, and the two other newly characterized ones are associated with crucial intramolecular and intermolecular interactions. Sequence homology of the area near the active site shows clearly that the catalytic triad of SA0302 is Glu41-Lys110-Cys146. We suggest also that the active site includes a fourth residue, the closely located Glu119. Despite an extensive similarity with other Nit-family structural folds, SA0302 displays an important difference. Protein loop 111–122, which follows the catalytic Lys110, is reduced to half the number of amino acids found in other Nit-family members. This leaves the active site fully accessible to solvent and substrates. We have identified conservative sequence motifs around the three core catalytic residues, which are inherent solely to Branch 10 of the nitrilase superfamily. On the basis of these new sequence fingerprints, 10 previously uncharacterized proteins also could be assigned to this hydrolase subfamily.

An animated interactive 3D complement (I3DC) is available in Proteopedia at http://proteopedia.org/w/Journal:JBSD:19  相似文献   
998.
Processes involved in the operation of the circadian pacemaker are well characterized; however; little is known about what mechanisms drive the overt diurnal, nocturnal, or crepuscular behavior in a species. In this context, dual‐phasing rodents, such as Octodon degus, emerge as a useful model to decipher these keys. Two main chronotypes, nocturnal and diurnal, have been traditionally described in laboratory‐housed degus based on the percentage of activity displayed by the animals during the scotophase or photophase. However, if one considers also the entrainment phase angle during the first days following a change from LD to DD conditions, a third chronotype (intermediate)—or more properly, a continuous grading of circadian expressions between diurnal and nocturnal chronotype—can be observed. Our experiments suggest the pacemaker of the diurnal animal is entrained to the photophase, and light does not exert a negative masking effect. The pacemaker of the nocturnal degus, on the other hand, is entrained to the scotophase, and light exerts a strong negative masking effect. Finally, the intermediate chronotype is characterized by variable negative masking effect of light overlapping a pacemaker entrained to the photophase. The phase shift inversion from diurnal to nocturnal chronotype is related to the availability of a wheel in the cage, and the effect may be located downstream from the clock. However, body temperature rhythm recordings, less affected by masking effects, point to an involvement of the circadian pacemaker in chronotype differentiation, as transient entrainment cycles, and not an abrupt phase shift, were detected after providing access to the wheel. The diurnality of degus seems to be the result of a variety of mechanisms, which may explain how different processes can lead to similar chronotypes.  相似文献   
999.
IMP preferring cytosolic 5 ′-nucleotidase II (cN-II) is a widespread enzyme whose amino acid sequence is highly conserved among vertebrates. Fluctuations of its activity have been reported in some pathological conditions and its mRNA levels have been proposed as a prognostic factor for poor outcome in patients with adult acute myeloid leukemia. As a member of the oxypurine cycle, cN-II is involved in the regulation of intracellular concentration of 5′-inosine monophosphate (IMP), 5′-guanosine monophosphate (GMP), and also 5-phosphoribose 1-pyrophosphate (PRPP) and is therefore involved in the regulation of purine and pyrimidine de novo and salvage synthesis. In addition, several studies demonstrated the involvement of cN-II in pro-drug metabolism. Notwithstanding some publications indicating that cN-II is essential for the survival of several cell types, its role in cell metabolism remains uncertain. To address this issue, we built two eucaryotic cellular models characterized by different cN-II expression levels: a constitutive cN-II knockdown in the astrocytoma cell line (ADF) by short hairpin RNA (shRNA) strategy and a cN-II expression in the diploid strain RS112 of Saccharomyces cerevisiae. Preliminary results suggest that cN-II is essential for cell viability, probably because it is directly involved in the regulation of nucleotide pools. These two experimental approaches could be very useful for the design of a personalized chemotherapy.  相似文献   
1000.
The temperature-sensitive hemagglutinin (Tsh) is a representative of the growing subfamily of secreted bacterial virulence factors, known as serine protease autotransporters of the Enterobacteriaceae (SPATEs). Expressed by avian and human pathogenic strains of Escherichia coli Tsh acts as a serine protease and an adhesin to erythrocytes, hemoglobin, and extracellular matrix proteins. Mature Tsh is comprised of a 106-kDa secreted domain (Tshs) and a 33-kDa outer membrane β-domain (Tshβ). Based on the size of β-domains and functional properties of their passenger domains, all SPATEs are considered to be conventional autotransporters. However, it is unsettled if the conventional autotransporters exist as monomers, oligomers, or multimers (e.g., hexamers). To determine the quaternary structure of Tsh in vitro, we purified Tshβ from the outer membranes and showed that it is natively folded because it is heat modifiable and resistant to protease digestion. Blue-native polyacrylamide gel electrophoresis of Tshβ indicated that Tshβ exists as a monomer or a dimer. The cross-linking analysis demonstrated that purified Tshβ exists as a monomer. The size-exclusion chromatography and cross-linking analyses of purified Tshs also showed that the passenger domain of Tsh is a monomer. Overall, our data indicated that Tsh is a monomeric protein in vitro and support the concept that the SPATE autotransporters exist as monomers rather than as multimers. Implications of our findings on the mechanism of autotransporter secretion across the outer membrane are discussed.  相似文献   
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