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91.
Synopsis Stocking of fish from other populations has been commonly employed for enhancement of wild brown trout, Salmo trutta, populations in north Spain. Young hatchery reared brown trout of central European origin were introduced into some Asturian rivers every year since 1984. Based on variation at the isozyme locus LDH-C1* and at the microsatellite locus BFRO 002, two genetic markers race-specific in Salmo trutta, we detected introgression of foreign genomes into native gene pools in some Spanish trout populations where only pure native individuals were present 10 years ago. We strongly suggest development of alternative management policies for conservation of Spanish natural brown trout populations without endangering the traditional recreational fisheries. Jorge I. Izquierdo, Ana G. F. Castillo: These two authors contributed equally to the article.  相似文献   
92.
93.
The signal produced by fluorescence in situ hybridization (FISH) often is inconsistent among cells and sensitivity is low. Small DNA targets on the chromatin are difficult to detect. We report here an improved nick translation procedure for Texas red and Alexa Fluor 488 direct labeling of FISH probes. Brighter probes can be obtained by adding excess DNA polymerase I. Using such probes, a 30 kb yeast transgene, and the rp1, rp3 and zein multigene clusters were clearly detected.  相似文献   
94.
The purpose of this study was to examine the effect of 3 volumes of heavy resistance, average relative training intensity (expressed as a percentage of 1 repetition maximum that represented the absolute kilograms lifted divided by the number of repetitions performed) programs on maximal strength (1RM) in Snatch (Sn), Clean & Jerk (C&J), and Squat (Sq). Twenty-nine experienced (>3 years), trained junior weightlifters were randomly assigned into 1 of 3 groups: low-intensity group (LIG; n = 12), moderate-intensity group (MIG; n = 9), and high-intensity group (HIG; n = 8). All subjects trained for 10 weeks, 4-5 days a week, in a periodized routine using the same exercises and training volume (expressed as total number of repetitions performed at intensities equal to or greater than 60% of 1RM), but different programmed total repetitions at intensities of >90-100% of 1RM for the entire 10-week period: LIG (46 repetitions), MIG (93 repetitions), and HIG (184 repetitions). During the training period, MIG and LIG showed a significant increase (p < 0.01-0.05) for C&J (10.5% and 3% for MIG and LIG, respectively) and Sq (9.5% and 5.3% for MIG and LIG, respectively), whereas in HIG the increase took place only in Sq (6.9%, p < 0.05). A calculation of effect sizes revealed greater strength gains in the MIG than in HIG or LIG. There were no significant differences between LIG and HIG training volume-induced strength gains. All the subjects in HIG were unable to fully accomplish the repetitions programmed at relative intensities greater than 90% of 1RM. The present results indicate that short-term resistance training using moderate volumes of high relative intensity tended to produce higher enhancements in weightlifting performance compared with low and high volumes of high relative training intensities of equal total volume in experienced, trained young weightlifters. Therefore, for the present population of weightlifters, it may be beneficial to use the MIG training protocol to improve the weightlifting program at least in a short-term (10 weeks) cycle of training.  相似文献   
95.
Hypertrophy of human mesangial cells (HMC) is among the earliest characteristics in patients with diabetic nephropathy (DN). Recently, we observed the upregulation of parathyroid hormone (PTH)-related protein (PTHrP) in experimental DN, associated with renal hypertrophy. Herein, we first examined whether PTHrP was overexpressed in human DN, and next assessed the putative role of this protein on high glucose (HG)-induced HMC hypertrophy. As previously found in mice, kidneys from diabetic patients showed an increased tubular and glomerular immunostaining for PTHrP. In HMC, HG medium increased PTHrP protein expression associated with the development of hypertrophy as assessed by cell protein content. This effect was also induced by PTHrP(1-36). HG and PTHrP(1-36)-induced hypertrophy were associated with an increase in cyclin D1 and p27Kip1 protein expression, a decreased cyclin E expression, and the prevention of cyclin E/cdk2 complex activation. Both PTHrP neutralizing antiserum (α-PTHrP) and the PTH/PTHrP receptor antagonist (JB4250) were able to abolish HG induction of hypertrophy, the aforementioned changes in cell cycle proteins, and also TGF-β1 up-regulation. Moreover, the capability of both HG and PTHrP(1-36) to induce HMC hypertrophy was abolished by α-TGFβ1. These data show for the first time that PTHrP is upregulated in the kidney of patients with DN. Our findings also demonstrate that PTHrP acts as an important mediator of HG-induced HMC hypertrophy by modulating cell cycle regulatory proteins and TGF-β1.  相似文献   
96.
Diatom cell quantity and their biochemical composition vary among species and are greatly affected by harvest stage or culture conditions. This study compares growth pattern, cell attachment, and biochemical composition of four diatoms suitable for abalone post-larvae: Navicula incerta, Proschkinia sp., Nitzschia sp., and Amphora sp. The four diatoms were grown in F/2 medium at 28.5?±?1.4°C, under 62?±?8?μmol?photons?m?2?s?1, at different original inoculating densities (0.05?×?106, 0.10?×?106, and 0.25?×?106?cells?mL?1) and were harvested in log and stationary phase of growth for biochemical analysis. Total protein, carbohydrate, lipid, and ash composition, as well as fatty acid composition, were determined. All diatoms grew better when inoculated at 0.10?×?106?cell?mL?1 with Proschkinia sp. reaching the highest cell density of 6.56?×?106?cells?mL?1 in log phase. Amphora sp. had the highest cell attachment capacity when inoculated at 0.10?×?106?cell?mL?1 (11,580?cells?mm?2), whereas N. incerta had the lowest (7,750?cells?mm?2). Protein and lipid (percent dry weight) contents were generally highest in cells during log phase of growth; Amphora sp. in log phase of growth had the highest lipid content of 9.74% DW, whereas significant differences in carbohydrate between the two growth phases were only observed for Proschkinia sp. Besides, all diatoms had higher energy contents in log phase of growth. There were no significant differences in ash content among the four diatoms. Polyunsaturated fatty acid (PUFA) content ranged from 23.25% to 38.62% of the total fatty acids, and the four diatoms tested were richer in n-3 PUFA than in n-6 PUFA. All the diatoms had significant quantities of 20:5n-3 (EPA) (between 12.69% and 17.68% of TFA), and Proschkinia sp., in log phase of growth, had the highest quantity of arachidonic acid (20:4n-6; ARA). The results highlight the influence of culture conditions and harvest protocols on diatom nutritive value and enabled a preliminary approach towards the selection of novel diatom species.  相似文献   
97.
The aim of this study was to evaluate the ability from a number of lactic acid bacteria isolated from different sources to produce glycosidase enzymes. Representative isolates (225) from clusters obtained after genotyping, using randomly amplified polymorphic DNA-polymerase chain reaction (RAPD-PCR) analysis, of 1,464 isolates, were screened for β-D-glucosidase activity. Thirty-five of them were selected for subsequent analysis. These strains were able to hydrolyze α-D-glucopyranoside, β-D-xylopyranoside and α-L-arabinofuranoside although β-D-glucosidase activity was the predominant activity for 22 of the selected strains. Only some of them did so with α-L-rhamnopyranoside. All of these were from wine samples and were identified as belonging to the Oenococcus oeni species using Amplification and Restriction Analysis of 16S-rRNA gene (16S-ARDRA). When the influence of pH, temperature and ethanol or sugars content on β-D-glucosidase activity was assayed, a strain-dependent response was observed. The β-D-glucosidase activity occurred in both whole and sonicated cells but not in the supernatants from cultures or obtained after cell sonication. Strains 10, 17, 21, and 23 retained the most β-D-glucosidase activity when they were assayed at the conditions of temperature, pH, ethanol and sugar content used in winemaking. These results suggest that these strains could be used as a source of glycosidase enzymes for use in winemaking.  相似文献   
98.
Iron deficiency anemia and zinc deficiency are major health concerns across the world and can be addressed by biofortification breeding of higher mineral concentration in staple crops, such as common bean. Wild common beans have for the most part had higher average seed mineral concentration than cultivars of this species but have small un-commercial seeds. A logical approach for the transfer of the seed mineral trait from wild beans to cultivated beans is through the advanced backcross breeding approach. The goal of this study was to analyze a population of 138 BC(2)F(3:5) introgression lines derived from the very high iron wild genotype G10022 backcrossed into the genetic background of the commercial-type variety 'Cerinza', a large-red seeded bush bean cultivar of the Andean genepool. In addition to measuring seed mineral accumulation traits and the quantitative trait loci (QTL) controlling these traits we were interested in simultaneously testing the adaptation of the introgression lines in two replicated yield trials. We found the cross to have high polymorphism and constructed an anchored microsatellite map for the population that was 1,554-cM long and covered all 11 linkage groups of the common bean genome. Through composite interval mapping (CIM) and single point analysis (SPA), we identified associations of markers and mineral traits on b01, b06, b07, b08, b10 and b11 for seed iron concentration, and markers on b01, b04 and b10 for seed zinc concentration. The b07 and b08 QTL aligned with previous QTL for iron concentration. A large number of QTL were found for seed weight (9 with CIM and 36 with SPA analysis) and correlations between seed size and mineral content affected the identification of iron and zinc contents' QTL on many linkage groups. Segregation distortion around domestication genes made some areas difficult to introgress. However, in conclusion, the advanced backcross program produced some introgression lines with high mineral accumulation traits using a wild donor parent.  相似文献   
99.

Background

Loss of arm-hand performance due to a hemiparesis as a result of stroke or cerebral palsy (CP), leads to large problems in daily life of these patients. Assessment of arm-hand performance is important in both clinical practice and research. To gain more insight in e.g. effectiveness of common therapies for different patient populations with similar clinical characteristics, consensus regarding the choice and use of outcome measures is paramount. To guide this choice, an overview of available instruments is necessary. The aim of this systematic review is to identify, evaluate and categorize instruments, reported to be valid and reliable, assessing arm-hand performance at the ICF activity level in patients with stroke or cerebral palsy.

Methods

A systematic literature search was performed to identify articles containing instruments assessing arm-hand skilled performance in patients with stroke or cerebral palsy. Instruments were identified and divided into the categories capacity, perceived performance and actual performance. A second search was performed to obtain information on their content and psychometrics.

Results

Regarding capacity, perceived performance and actual performance, 18, 9 and 3 instruments were included respectively. Only 3 of all included instruments were used and tested in both patient populations. The content of the instruments differed widely regarding the ICF levels measured, assessment of the amount of use versus the quality of use, the inclusion of unimanual and/or bimanual tasks and the inclusion of basic and/or extended tasks.

Conclusions

Although many instruments assess capacity and perceived performance, a dearth exists of instruments assessing actual performance. In addition, instruments appropriate for more than one patient population are sparse. For actual performance, new instruments have to be developed, with specific focus on the usability in different patient populations and the assessment of quality of use as well as amount of use. Also, consensus about the choice and use of instruments within and across populations is needed.  相似文献   
100.

Introduction

Rheumatoid arthritis (RA) is an autoimmune disease characterized by inflammation of the joints and the presence of autoantibodies directed against proteins containing the non-standard arginine-derived amino acid citrulline. The protein fibrinogen, which has an essential role in blood clotting, is one of the most prominent citrullinated autoantigens in RA, particularly because it can be found in the inflamed tissue of affected joints. Here, we set out to analyze the presence of citrullinated endogenous peptides in the synovial fluid of RA and arthritic control patients.

Methods

Endogenous peptides were isolated from the synovial fluid of RA patients and controls by filtration and solid phase extraction. The peptides were identified and quantified using high-resolution liquid chromatography-mass spectrometry.

Results

Our data reveal that the synovial fluid of RA patients contains soluble endogenous peptides, derived from fibrinogen, containing significant amounts of citrulline residues and, in some cases, also phosphorylated serine. Several citrullinated peptides are found to be more abundantly present in the synovial fluid of RA patients compared to patients suffering from other inflammatory diseases affecting the joints.

Conclusions

The increased presence of citrullinated peptides in RA patients points toward a possible specific role of these peptides in the immune response at the basis of the recognition of citrullinated peptides and proteins by RA patient autoantibodies.  相似文献   
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