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41.
42.

Background  

Optical imaging is an attractive non-invasive way to evaluate the expression of a transferred DNA, mainly thanks to its lower cost and ease of realization. In this study optical imaging was evaluated for monitoring and quantification of the mouse knee joint and tibial cranial muscle electrotransfer of a luciferase encoding plasmid. Optical imaging was applied to study the kinetics of luciferase expression in both tissues.  相似文献   
43.

Background  

Mass spectrometry has become a powerful tool for the analysis of large numbers of proteins in complex samples, enabling much of proteomics. Due to various analytical challenges, so far no proteome has been sequenced completely. O'Shea, Weissman and co-workers have recently determined the copy number of yeast proteins, making this proteome an excellent model system to study factors affecting coverage.  相似文献   
44.
Summary

Bulinus truncatus is the intermediate host of Schistosoma haematobium, a trematode parasite causing bladder bilharziasis in man. In the struggle against this disease, control of snail populations is an important goal and expansion of our knowledge of the reproductive activity of Bulinus is relevant in this regard.

In this study the effects of various factors on the fecundity of Bulinus were investigated in specimens kept under continuous water refreshment conditions. The results are considered to be more indicative of the natural situation than results obtained under the current use of discontinuous water refreshment.

Isolated snails produce considerably higher numbers of egg masses and eggs than grouped snails. The effect of grouping on isolated snails, and the reverse situation, is very rapid, being fully effective within one week. The increase in fecundity of isolated snails is most probably caused by the absence of copulatory activity, since transfer of semen is known to curtail egg laying in freshwater pulmonate snails. Egg mass production was shown to decrease with increasing population density. This may be caused either by the difference in space available or by the possible difference in copulatory activity. Isolated snails showed a faster body growth than grouped snails.

The possible role of hormones involved in establishing the above effects and the consequences of the results for snail control programs are discussed.  相似文献   
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Diagnosis of bacterial sepsis in preterm neonates can be difficult when using serum markers that rely on physiological changes because these changes may not necessarily be the result of bacterial infections alone. This retrospective investigation explores the potential use of the DNA methylation pattern of CpG sites in the promoter region of the calcitonin-related polypeptide α (CALCA) gene as an epigenetic biomarker for bacterial sepsis in preterm newborns. Four novel changes in the DNA methylation of eight CpG sites were detected in this gene and are present only in neonates with bacterial sepsis: (1) partial methylation at -769 CpG in gram-negative or gram-positive early onset sepsis (EOS) and late onset sepsis (LOS) episodes; (2) demethylation of 8 CpGs in gram-negative EOS followed by LOS (ELS) and in gram-negative EOS; (3) demethylation of 7 CpGs in gram-positive ELS and gram-positive EOS; (4) -771 C:G > T:A; 5′ de novo -778 CpG mutation on both alleles in EOS. These changes were not detected in birth weight and gestational age matched controls or in newborns with isolated infections. Our results indicate that the DNA methylation pattern of the promoter region of the CALCA gene varies in different types of bacterial preterm sepsis, thus suggesting a potential use as an epigenetic biomarker. A prospective confirmation of these results is essential.  相似文献   
48.
Production of alcohol-free beer by limited fermentation is optimally performed in a packed-bed reactor. This highly controllable system combines short contact times between yeast and wort with the reduction of off-flavors to concentrations below threshold values. In the present study, the influence of immobilization of yeast to DEAE-cellulose on sugar fermentation and aldehyde reduction was monitored. Immobilized cells showed higher activities of hexokinase and pyruvate decarboxylase compared to cells grown in batch culture. In addition, a higher glucose flux was observed, with enhanced excretion of main fermentation products, indicating a reduction in the flux of sugar used for biomass production. ADH activity was higher in immobilized cells compared to that in suspended cells. However, during prolonged production a decrease was observed in NAD-specific ADH activity, whereas NADP-specific activity increased in the immobilized cells. The shifts in enzyme activities and glucose flux correlate with a higher in vivo reduction capacity of the immobilized cells.  相似文献   
49.
In this study, the use of fermented Hass avocado kernel (FHK) with Lactobacillus plantarum to produce functional biscuits was examined. The chemical composition and antinutrient factors were evaluated for raw and fermented Hass avocado kernels. Fatty acids were separated by gas liquid chromatography. The physical properties, color, and sensory attributes of the biscuits were assessed using professional methods. The protein increased by 54% after fermentation to become (7.93%) in FHK while it was 5.15% in raw Hass avocado kernel (RHK). The crude fiber and ash decreased after fermentation by 18% and 8%, respectively. A significant (p < 0.05) increase was recorded in total phenol content, antiradical effect against DPPH and flavonoid content of FHK compared with RHK. After fermentation, reduction of tannins content was 80.76%, oxalates content 89.95%, alkaloids 70%, while traces of phytates and saponin were detected. The relative density, saponification value and iodine value of FHK oil were 0.917 g/ml, 212.26 mg KOH/g oil and 72.74 g Iodine/100 g oil, respectively. FHK oil had the following sequence: PUFA (51.54%) > SFA (26.72%) > MUFA (21.83%). The highest spread ratio (6.17) was recorded in biscuits produced by replacing 10% of FHK. Difference between the biscuit samples in the color from all treatments was completely compatible with the sensory evaluation results. Substituting 5% and 10% of FHK flour significantly improved both the brittleness and the total percentage of replacement.  相似文献   
50.

Background

An important goal of Zebu breeding programs is to improve reproductive performance. A major problem faced with the genetic improvement of reproductive traits is that recording the time for an animal to reach sexual maturity is costly. Another issue is that accurate estimates of breeding values are obtained only a long time after the young bulls have gone through selection. An alternative to overcome these problems is to use traits that are indicators of the reproductive efficiency of the herd and are easier to measure, such as age at first calving. Another problem is that heifers that have conceived once may fail to conceive in the next breeding season, which increases production costs. Thus, increasing heifer’s rebreeding rates should improve the economic efficiency of the herd. Response to selection for these traits tends to be slow, since they have a low heritability and phenotypic information is provided only later in the life of the animal. Genome-wide association studies (GWAS) are useful to investigate the genetic mechanisms that underlie these traits by identifying the genes and metabolic pathways involved.

Results

Data from 1853 females belonging to the Agricultural Jacarezinho LTDA were used. Genotyping was performed using the BovineHD BeadChip (777 962 single nucleotide polymorphisms (SNPs)) according to the protocol of Illumina - Infinium Assay II ® Multi-Sample HiScan with the unit SQ ™ System. After quality control, 305 348 SNPs were used for GWAS. Forty-two and 19 SNPs had a Bayes factor greater than 150 for heifer rebreeding and age at first calving, respectively. All significant SNPs for age at first calving were significant for heifer rebreeding. These 42 SNPs were next or within 35 genes that were distributed over 18 chromosomes and comprised 27 protein-encoding genes, six pseudogenes and two miscellaneous noncoding RNAs.

Conclusions

The use of Bayes factor to determine the significance of SNPs allowed us to identify two sets of 42 and 19 significant SNPs for heifer rebreeding and age at first calving, respectively, which explain 11.35 % and 6.42 % of their phenotypic variance, respectively. These SNPs provide relevant information to help elucidate which genes affect these traits.  相似文献   
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