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41.
Sechi T  Usai MG  Miari S  Mura L  Casu S  Carta A 《Animal genetics》2007,38(6):614-620
The aim of this work was to develop a strategy for using a genetic analysis for identifying native animals in regions where local breeds have been crossed with improved breeds and then compare that strategy to the overall morphology and breeding histories of the herds for identifying these animals. The experiment included the Sardinian goat population, which is a crossbred of native animals with the Maltese breed. Whole herds were assigned to Maltese (five herds; 49 animals), crossbred (18 herds; 117 animals) or Sardinian (12 herds; 164 animals) groups. For the genetic analysis, genotypes of 22 microsatellites were determined on 330 animals, and basic measurements of genetic diversity were calculated. Genetic variability in the microsatellites was different in the three groups. High positive F IS showed that inbreeding existed in the subpopulations. The index of genetic differentiation, Nei's standard genetic distance and Reynolds' genetic distance were calculated and found to be significantly different between the three groups. The Sardinian and Maltese groups were the most distant whereas the crossbred group was closer to the Sardinian group. The proportion of the genome derived from two ancestral populations (native Sardinian and Maltese) was assessed using the structure software. Animals were assigned to three clusters on the basis of native Sardinian thresholds. A good correspondence between the empirical (morphology and breeding histories) and the objective genetic analysis was found. Both approaches indicate the presence of three different subpopulations in the Sardinian goat population.  相似文献   
42.
Thermal denaturation of Euphorbia latex amine oxidase (ELAO) has been studied by enzymatic activity, circular dichroism and differential scanning calorimetry. Thermal denaturation of ELAO is shown to be an irreversible process. Checking the validity of two-state it really describes satisfactorily the thermal denaturation of ELAO. Based on this model we obtain the activation energy, parameter T(*) (the absolute temperature at which the rate constant of denaturation is equal to 1 min(-1)), and total enthalpy of ELAO denaturation. HPLC experiments show that the thermal denatured enzyme conserves its dimeric state. The N(2)-->kD(2) model for thermal denaturation of ELAO is proposed: where N(2) and D(2) are the native and denatured dimer, respectively.  相似文献   
43.
PURPOSE: Although relatively rare, uveal melanoma is the most common ocular tumor of adults. Up to half of uveal melanoma patients die of metastatic disease. CXCR4, a chemokine receptor, is a prognostic factor in cutaneous melanoma involved in angiogenesis and metastasis formation. The aim of this study was to evaluate the expression of CXCR4 in uveal melanoma. METHODS: CXCR4 was detected by immunohistochemistry in 44 samples of uveal melanoma. Staining was categorized into three semiquantitative classes based on the rate of stained (positive) tumor cells: absence of staining, <50% of cell (+) and >50% (++). Correlations between CXCR4 expression, data on patient and tumor features were studied by contingency tables and the chi2 test. Time-to-event curves were studied using the Kaplan-Meier method. Univariate analysis was performed using the log-rank test. Ninety-five percent confidence intervals (95% CI) of hazard ratios were also reported. RESULTS: Staining for CXCR4 protein was absent in 18 tumors (40.9%), present in <50% of cells in 19 (43.2%) and in >50% of cells in 7 (15.9%) tumors. CXCR4 expression correlated to the epithelioid-mixed cell type (P=0.030). No statistically significant relation emerged between CXCR4 expression, largest tumor diameter (LTD) and extracellular matrix patterns as evaluated through histological patterns stained with periodic acid-Schiff (PAS). Events occurred in 2 out of 18 patients (11.1%) with negative tumors (2 deaths), in 3 out of 19 patients (15.8%) with <50% of positive tumor cells (2 deaths and 1 occurrence of metastases) and in 1 out of 7 patients (14.3%) with >50% of positive tumor cells (1 occurrence of metastases). The cell type (P=0.0457) but not CXCR4 showed prognostic value at univariate analysis. CONCLUSION: This study shows that CXCR4 is commonly expressed in uveal melanoma and correlates with cell type a well-established prognostic factor.  相似文献   
44.
Pentraxin 3 (PTX3) is an acute-phase protein, which can be produced by a variety of tissue cells at the site of infection or inflammation. It plays an important role in innate immunity in the lung and in mediating acute lung injury. The aim of this study was to determine the effect of mechanical ventilation on PTX3 expression in multiple lung injury models. Male Sprague-Dawley rats were challenged with intravenous injection of lipopolysaccharide (LPS) or hemorrhage followed by resuscitation (HS). The animals were then subjected to either relatively higher (12 ml/kg) or lower (6 ml/kg, positive end-expiratory pressure of 5 cmH(2)O) volume ventilation for 4 h. High-volume ventilation significantly enhanced PTX3 expression in the lung, either alone or in combination with LPS or hemorrhage. A significant increase of PTX3 immunohistochemistry staining in the lung was seen in all injury groups. The PTX3 expression was highly correlated with the severity of lung injury determined by blood gas, lung elastance, and wet-to-dry ratio. To determine the effects of HS, LPS, or injurious ventilation (25 ml/kg) alone on PTX3 expression, another group of rats was studied. Injurious ventilation significantly damaged the lung and increased PTX3 expression. A local expression of PTX3 induced by high-volume ventilation, either alone or in combination with other pathological conditions, suggests that it may be an important mediator in ventilator-induced lung injury.  相似文献   
45.
An alpha-amylase secreted by Pichia burtonii 15-1 isolated from a traditional starter murcha of Nepal, named Pichia burtonii alpha-amylase (PBA), was studied. The gene was cloned and its nucleotide sequence was determined. PBA was deduced to consist of 494 amino acid residues. It shared certain degrees of amino acid sequence identity with other homologous proteins: 60% with Schwanniomyces occidentalis alpha-amylase, 58% with Saccharomycopsis sp. alpha-amylase, and 47% with Taka-amylase A from Aspergillus oryzae. A three-dimensional structural model of PBA generated using the known three-dimensional structure of Taka-amylase A as a template suggested high structural similarity between them. Kinetic analysis revealed that the K(m) values of PBA were lower than those of Taka-amylase A for the oligosaccharides. Although the k(cat) values of PBA were lower than those of Taka-amylase A for the oligosaccharide substrates, the k(cat)/K(m) values of PBA were higher.  相似文献   
46.
The present study investigated the effect of unilateral and bilateral resistance exercise (RE) on maximal voluntary strength, total volume of load lifted (TVLL), rating of perceived exertion (RPE) and blood lactate concentration of resistance-trained males. Twelve healthy men were assessed for the leg extension one-repetition maximum (1RM) strength using bilateral and unilateral contractions. Following this assessment, an RE session (3 sets of repetitions to failure) was conducted with bilateral and unilateral (both limbs) contractions using a load of 50% 1RM. The TVLL was calculated by the product of the number of repetitions and the load lifted per repetition. RPE and blood lactate were measured before, during and after each set. Session RPE was measured 30 minutes after RE sessions. There was a significant difference in the bilateral (120.0±11.9) and unilateral (135.0±20.2 kg) 1RM strength (p < 0.05). The TVLL was similar between both RE sessions. Although the repetitions decreased with each successive set, the total number of repetitions completed in the bilateral protocol (48) was superior to the unilateral (40) protocol (p < 0.05). In both bouts, RPE increased with each subsequent set whilst blood lactate increased after set 1 and thereafter remained stable (p < 0.05). The RPE and lactate responses were not significantly different between both sessions. In conclusion, a bilateral deficit in leg extension strength was confirmed, but the TVLL was similar between both RE sessions when exercising to voluntary fatigue. This outcome could be attributed to the number of repetitions completed in the unilateral RE bout. The equal TVLL would also explain the similar perceptual and metabolic responses across each RE session.  相似文献   
47.
The effects of different nitrogen fertilization regimes on body size and selected life‐history parameters (development time, survival, fecundity and fertility) of the vine mealybug, Planococcus ficus (Signoret) (Hemiptera: Pseudococcidae), were investigated on potted grapevines under laboratory and screenhouse conditions. In both trials, five groups of four grapevines each were supplied with 0, 0.25, 0.5, 1.0 or 2.0 g/l of ammonium nitrate fertilizer for a month and then artificially infested with 200 first‐instar vine mealybugs (24 h of age). The concentration of nitrogen on grape leaves was measured during both experiments by a SPAD chlorophyll metre, showing statistical differences among treatments. The nitrogen fertilization significantly affected the investigated P. ficus parameters, providing consistent results in both laboratory and screenhouse trials. The vine mealybug females exhibited higher survival and fecundity, larger body size and lower development time on plants supplied with higher nitrogen fertilization rates. Survival, body size and fecundity of P. ficus were positively correlated with the leaf nitrogen concentration, whereas the development time was negatively correlated. Fertility did not vary significantly among treatments. Our results show that high nitrogen regimes increase the reproductive performance of P. ficus on grapevines and point out the importance of implementing balanced fertilization plans in grapevine IPM programs to reduce population densities and prevent insect outbreaks.  相似文献   
48.

Background  

Bioinformatic analyses typically proceed as chains of data-processing tasks. A pipeline, or 'workflow', is a well-defined protocol, with a specific structure defined by the topology of data-flow interdependencies, and a particular functionality arising from the data transformations applied at each step. In computer science, the dataflow programming (DFP) paradigm defines software systems constructed in this manner, as networks of message-passing components. Thus, bioinformatic workflows can be naturally mapped onto DFP concepts.  相似文献   
49.
Longu S  Mura A  Padiglia A  Medda R  Floris G 《Phytochemistry》2005,66(15):1751-1758
Copper/quinone amine oxidases contain Cu(II) and the quinone of 2,4,5-trihydroxyphenylalanine (topaquinone; TPQ) as cofactors. TPQ is derived by post-translational modification of a conserved tyrosine residue in the protein chain. Major advances have been made during the last decade toward understanding the structure/function relationships of the active site in Cu/TPQ amine oxidases using specific inhibitors. Mechanism-based inactivators are substrate analogues that bind to the active site of an enzyme being accepted and processed by the normal catalytic mechanism of the enzyme. During the reaction a covalent modification of the enzyme occurs leading to irreversible inactivation. In this review mechanism-based inactivators of plant Cu/TPQ amine oxidases from the pulses lentil (Lens esculenta), pea (Pisum sativum), grass pea (Lathyrus sativus) and sainfoin (Onobrychis viciifolia,) are described. Substrates forming, in aerobiotic and in anaerobiotic conditions, killer products that covalently bound to the quinone cofactor or to a specific amino acid residue of the target enzyme are all reviewed.  相似文献   
50.
2-Alkylamino-6-[1-(2,6-difluorophenyl)alkyl]-3,4-dihydro-5-alkylpyrimidin-4(3H)-ones (F(2)-NH-DABOs) 4, 5 belonging to the dihydro-alkoxy-benzyl-oxopyrimidine (DABO) family and bearing different alkyl- and arylamino side chains at the C(2)-position of the pyrimidine ring were designed as active against wild type (wt) human immunodeficiency virus type 1 (HIV-1) and some relevant HIV-1 mutants. Biological evaluation indicated the importance of the further anchor point of compounds 4, 5 into the non-nucleoside binding site (NNBS): newly synthesized compounds were highly active against both wild type and the Y181C HIV-1 strains. In anti-wt HIV-1 assay the potency of amino derivatives did not depend on the size or shape of the C(2)-amino side chain, but it associated with the presence of one or two methyl groups (one at the pyrimidine C(5)-position and the other at the benzylic carbon), being thymine, alpha-methyluracil or alpha-methylthymine derivatives almost equally active in reducing wt HIV-1-induced cytopathogenicity in MT-4 cells. Against the Y181C mutant strain, 2,6-difluorobenzyl-alpha-methylthymine derivatives 4d, 5h'-n' showed the highest potency and selectivity among tested compounds, both a properly sized C(2)-NH side chain and the presence of two methyl groups (at C(5) and benzylic positions) being crucial for high antiviral action.  相似文献   
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