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101.
Summary Responses from four generations of index selection for egg production to 280 days of age in four White Leghorn populations have been presented. A pedigreed randombred population derived from one of the lines was reared with the selected lines to measure the environmental trend. The magnitude of total as well as average response although varying from population to population was positive in all the lines studied. Close correspondence between predicted and realized gains indicated that natural selection, genotype environmental interactions and environmental fluctuations were unimportant during the course of selection. Realized heritabilities agreed fairly well with the estimated heritabilities in at least three out of four populations studied. Probable reasons for variable and insufficient response were investigated.  相似文献   
102.
103.
An esterase (EC 3.1.1.1) produced by an isolated strain of Bacillus subtilis RRL 1789 exhibited moderate to high enantioselectivity in the kinetic resolution of several substrates like aryl carbinols, hydroxy esters, and halo esters. The enzyme named as B. subtilis esterase (BSE), was purified to >95% purity with a specific activity of 944 U/mg protein and 12% overall yield. The purified enzyme is approximately 52 kDa monomer, maximally activity at 37 degrees C and pH 8.0 and fairly stable up to 55 degrees C. The enzyme does not exhibit the phenomenon of interfacial activation with tributyrin and p-nitrophenyl butyrate beyond the saturation concentration. The enzyme showed preference for triacyglycerols and esters of p-nitrophenol with short chain fatty acid. Presence of Ca2+ ions increases the activity of enzyme by approximately 20% but its presence does not have any influence on the thermostability of the enzyme. The enzyme is not a metalloprotein and belongs to the family of serine proteases. The N-terminal amino acid sequence of BSE determined, as Met-Thr-Pro-Glu-Iso-Val-Thr-Thr-Glu-Tyr-Gly- revealed similarity with the N-terminal amino acid sequence of p-nitrobenzylesterase of B. subtilis.  相似文献   
104.
105.

Background

The placenta is an important site for iron metabolism in humans. It transfers iron from the mother to the fetus. One of the major iron transport proteins is transferrin, which is a blood plasma protein crucial for iron uptake. Its localization and expression may be one of the markers to distinguish placental dysfunction.

Methods

In the experimental study we used antibody preparation, mass spectrometric analysis, biochemical and immunocytochemical methods for characterization of transferrin expression on the human choriocarcinoma cell line JAR (JAR cells), placental lysates, and cryostat sections. Newly designed monoclonal antibody TRO-tf-01 to human transferrin was applied on human placentae from normal (n = 3) and abnormal (n = 9) pregnancies.

Results

Variations of transferrin expression were detected in villous syncytiotrophoblast, which is in direct contact with maternal blood. In placentae from normal pregnancies, the expression of transferrin in the syncytium was significantly lower (p < 0.001) when compared to placentae from abnormal ones (gestational diabetes, pregnancy induced hypertension, drug abuse).

Conclusion

These observations suggest that in the case of abnormal pregnancies, the fetus may require higher levels of transferrin in order to prevent iron depletion due to the stress from the placental dysfunction.  相似文献   
106.
Cyclophilins are omnipresent proteins found in eukaryotes and prokaryotes, with presence in cytoplasm as well as in nucleus. Primary role of Cyclophilins is of peptidyl-prolyl cis–trans isomerase, a molecular chaperon action. Here, we report sequence-specific 1H, 13C and 15N resonance assignments for a Cyclophilin A like protein from Piriformospora indica. This protein is up-regulated during salt stress conditions.  相似文献   
107.
The important role of the cytoskeletal scaffold is increasingly recognized in host-pathogen interactions. The cytoskeleton potentially functions as a weapon for both the plants defending themselves against fungal or oomycete parasites, and for the pathogens trying to overcome the resisting barrier of the plants. This concept, however, had not been investigated in marine algae so far. We are opening this scientific chapter with our study on the functional implications of the cytoskeleton in 3 filamentous brown algal species infected by the marine oomycete Eurychasma dicksonii. Our observations suggest that the cytoskeleton is involved in host defense responses and in fundamental developmental stages of E. dicksonii in its algal host.Oomycetes are important plant and animal pathogens and are the cause of significant crop losses every year. Hence, a plethora of studies with different cultivated and model plant species investigate the diversity of parasite infection pathways and host defense responses.1 However, little information is available on the interactions between algae and marine oomycetes, despite the epidemic outbreaks reported2 and the huge impact on intensive algal aquaculture.3Eurychasma dicksonii is a biotrophic, intracellular marine oomycete, capable to infect at least 45 species of brown seaweeds in laboratory cultures.4 Molecular data reveal that E. dicksonii has a basal phylogenetic position in the oomycete lineage.5,6 The basic stages of the infection are known: the attachment of the parasite spore to the host cell wall, the penetration of its cytoplasm into the host cell, the formation of a multinucleated, unwalled thallus, and zoosporogenesis.6 Hitherto, though, there was no knowledge about the role of cytoskeleton in the context of infection, which stimulated our research.In land plants, reorganization of the cytoskeleton is part of the reaction to infection by fungal pathogens. The rearrangement of the cytoplasm and the relocation of the nuclei and other organelles are accompanied by rapid rearrangements of the cytoskeletal elements.7 The plant cytoskeleton shows an extreme plasticity in order to serve the intracellular realignment.At the same time, this indicates that the plant cytoskeleton could be the parasite’s target by producing anti-cytoskeletal compounds in an effort to overcome plant resistance, a mechanism known in several fungal and oomycete pathogens of higher plants.8,9Consequently, the changes in microtubule (MT) organization are associated with both the plant defense and/or susceptibility toward oomycetes, respectively.10 Therefore, our research on the organization and role of cytoskeleton in the host and the parasite sheds some light into the enormous variability in the specificity of the recognition, defense, and infection mechanisms.  相似文献   
108.
The aim of this study was to assess and characterize the stability of multilamellar liposomes as a delivery vehicle for triamcinolone acetonide. A standardized preparation method for a liposomal delivery vehicle was developed, after varying composition and storage conditions, and assessing encapsulation efficiency and loss of active principle. The assessment of temperature as a factor in formula stability during storage showed that stability improved under refrigeration (4–6°C) (less early diffusion of active principle through the liposomal wall), in comparison with samples stored at room temperature. To improve stability, cholesterol was added to some formulae, which although resulting in a decrease in average encapsulation efficiency, mitigated subsequent losses of retained active principle (formulae 4, 5, and 6), in comparison with those without cholesterol (formulae 1, 2, and 3). This was evident both under refrigerated and room-temperature conditions. Finally, after testing the effects of adding an antioxidant and/or preservative to the formulae, a liposomal design was achieved with acceptable stability, vesicle dimensions, and encapsulation efficiency.  相似文献   
109.
Cartilage calcification contributes to the development and progression of osteoarthritis (OA). It has been well-investigated adiponectin regulates vascular calcification. The purpose of this study is to investigate the therapeutic value and the molecular mechanism of AdipoRon, an adiponectin receptor agonist, on the chondrocytes calcification. Primary chondrocytes were isolated and cultured from normal cartilage and OA cartilage. The calcification in tissues was evaluated by inductively coupled plasma/atomic emission spectroscopy and alizarin red S staining. The calcification in chondrocytes was determined using the alkaline phosphatase (ALP) staining and an ALP assay kit. The cellular effects of AdipoRon were assessed by immunofluorescence staining and Western blot analysis. We found that calcification was significantly increased in OA cartilage tissues and cells. Importantly, the degree of calcification and ALP activity of the OA chondrocytes was decreased upon the treatment with AdipoRon. The AdipoRon-induced cellular effects, including the reduction of the calcification of chondrocytes and improvement of autophagy, were blocked by dorsomorphin, an 5′-adenosine monophosphate-activated protein kinase (AMPK) inhibitor. Moreover, autophagy activation by AdipoRon was mediated by the AMPK-mammalian target of rapamycin (mTOR) signaling pathway. Our results suggest that AdipoRon significantly alleviates the calcification of OA chondrocytes via activating AMPK-mTOR signaling to promote autophagy. Therefore, AdipoRon could be a potential therapeutic agent for the prevention and treatment of OA.  相似文献   
110.
The XI International Rotifer Symposium was held during 11–18 March, 2006 at the National Autonomous University of Mexico Campus Iztacala located at the North Mexico City (Mexico). These triennial international meetings, first organized in Austria by Late Ruttner-Kolisko in September 1976, are gradually becoming the focal point of discussion and collaboration from rotifer workers across the world. The present XI symposium was attended by 125 participants from 20 nations. During this meeting, different themes of rotifer research from morphology to molecular biology were considered. In addition, there were four invited lectures and four workshops covering different themes of the symposium. During the last 30 years, rotifer research has witnessed gradual shift from the conventional morphological taxonomy to molecular and evolutionary systematics. While the basic rotifer ecological studies continue today, applied areas such as ecotoxicology and aquaculture have taken key roles in the recent meetings. The international rotifer meetings provide ample opportunities not only for exchange of ideas and recent research, but also for material and in establishing inter-personal relationships. Over the last 30 years, the number of participants attending the rotifer meetings has increased.  相似文献   
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