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91.
92.
Ungerfeld R Suárez G Carbajal B Silva L Laca M Forsberg M Rubianes E 《Theriogenology》2003,60(1):35-45
The "ram effect" (RE) is an inexpensive technique that allows farmers to obtain out-of-season lambs. Five hundred and ninety-six Corriedale ewes were used in three experiments to determine the effectiveness of different medroxyprogesterone (MAP) treatments associated with the ram effect during the nonbreeding season. The aim of the first experiment was to evaluate the effectiveness of short-term (6-day) MAP priming. We obtained similar results in estrus incidence and fertility after using MAP sponges for 6, 9, and 13 days. In the second experiment, we compared the effect of sponges containing 20, 40, or 60 mg of MAP used in 6-day priming. Estrous behavior and fertility were not affected by dosage. In the third experiment, 2.5mg of MAP was administered in single treatments 0, 1, 3, or 5 days before the introduction of the rams. Medroxyprogesterone administration 1, 3, or 5 days before the introduction of the rams concentrated estrus in ewes 17 to 20 days later. 相似文献
93.
Concha MI Molina S Oyarzún C Villanueva J Amthauer R 《Fish & shellfish immunology》2003,14(3):259-273
Antimicrobial proteins and peptides play an important role in the primary defence of epithelial barriers in vertebrates and invertebrates. Here we report the detection of the apolipoproteins A-I and A-II in the epidermis and epidermal mucus of the carp (Cyprinus carpio L.) by immunohistochemistry and Western blot analysis. Both apolipoproteins are major constituents of high density lipoprotein and have been shown to display antiviral and antimicrobial activity in mammals. Therefore the aim of this study was to evaluate if they could be part of the innate immune system of teleost fish. A cDNA clone containing most of the coding region for carp apoA-I was isolated and used as a probe to demonstrate the expression of apoA-I gene in the skin. In addition, mucus apoA-I was shown to be associated to small particles that could correspond to nascent HDL. Finally, affinity purified plasma HDL displayed bactericidal activity in vitro against a non-pathogenic Escherichia coli strain, suggesting a defensive role for HDL and its associated proteins in the carp epidermis and mucus. 相似文献
94.
The ubiquitin-like hPLIC proteins can associate with proteasomes, and hPLIC overexpression can specifically interfere with ubiquitin-mediated proteolysis (Kleijnen et al., 2000). Because the hPLIC proteins can also interact with certain E3 ubiquitin protein ligases, they may provide a link between the ubiquitination and proteasomal degradation machineries. The amino-terminal ubiquitin-like (ubl) domain is a proteasome-binding domain. Herein, we report that there is a second proteasome-binding domain in hPLIC-2: the carboxyl-terminal ubiquitin-associated (uba) domain. Coimmunoprecipitation experiments of wild-type and mutant hPLIC proteins revealed that the ubl and uba domains each contribute independently to hPLIC-2-proteasome binding. There is specificity for the interaction of the hPLIC-2 uba domain with proteasomes, because uba domains from several other proteins failed to bind proteasomes. Furthermore, the binding of uba domains to polyubiquitinated proteins does not seem to be sufficient for the proteasome binding. Finally, the uba domain is necessary for the ability of full-length hPLIC-2 to interfere with the ubiquitin-mediated proteolysis of p53. The PLIC uba domain has been reported to bind and affect the functions of proteins such as GABAA receptor and presenilins. It is possible that the function of these proteins may be regulated or mediated through proteasomal degradation pathways. 相似文献
95.
96.
Brenner RR 《Prostaglandins, leukotrienes, and essential fatty acids》2003,68(2):151-162
Animal biosynthesis of high polyunsaturated fatty acids from linoleic, alpha-linolenic and oleic acids is mainly modulated by the delta6 and delta5 desaturases through dietary and hormonal stimulated mechanisms. From hormones, only insulin activates both enzymes. In experimental diabetes mellitus type-1, the depressed delta6 desaturase is restored by insulin stimulation of the gene expression of its mRNA. However, cAMP or cycloheximide injection prevents this effect. The depression of delta6 and delta5 desaturases in diabetes is rapidly correlated by lower contents of arachidonic acid and higher contents of linoleic in almost all the tissues except brain. However, docosahexaenoic n-3 acid enhancement, mainly in liver phospholipids, is not explained yet. In experimental non-insulin dependent diabetes, the effect upon the delta6 and delta5 desaturases is not clear. From all other hormones glucagon, adrenaline, glucocorticoids, mineralocorticoids, oestriol, oestradiol, testosterone and ACTH depress both desaturases, and a few hormones: progesterone, cortexolone and pregnanediol are inactive. 相似文献
97.
Vonasek E Mateu L Luzzati V Marquez G Vargas R Céspedes G Cotúa M Borges J 《European biophysics journal : EBJ》2001,30(1):11-16
A sural nerve dissected from a recently dead patient displayed an unusual X-ray diffraction pattern, suggesting that in situ and at the time of the patient's death the myelin sheaths were in a swollen state. Diffraction patterns of the swollen type were also recorded from: (1) a sural nerve from the corpse of a neurologically healthy person after soaking the nerve with Ringer solution at pH 5.5; (2) sciatic nerves dissected from rat cadavers at increasing time after death. In all the cases the swollen patterns reversed to the native type upon superfusion with Ringer solution at pH 7.3. The postmortem effect is to decrease the pH of the fluids surrounding the nerves in the cadavers. Our experiments show that the early postmortem processes have the effect of acidifying PNS nerves and that as a consequence of acidification the myelin sheaths swell. 相似文献
98.
A new broad-host-range plasmid, pSL1211, was constructed for the over-expression of genes in Synechocystis sp. strain PCC 6803. The plasmid was derived from RSF1010 and an Escherichia coli over-expression plasmid, pTrcHisC. Over-expressed protein is made with a removable N-terminal histidine tag. The plasmid was used to over-express the phrA gene and purify the gene product from Synechocystis sp. strain PCC 6803. PhrA is the major ultraviolet-light-resistant factor in the cyanobacterium. The purified PhrA protein exhibited an optical absorption spectrum similar to that of the cyclobutane pyrimidine dimer (CPD) DNA photolyase from Synechocuccus sp. strain PCC 6301 (Anacystis nidulans). Mass spectrometry analysis of PhrA indicated that the protein contains 8-hydroxy-5-deazariboflavin and flavin adenine dinucleotide (FADH2) as cofactors. PhrA repairs only cyclobutane pyrimidine dimer but not pyrimidine (6-4) pyrimidinone photoproducts. On the basis of these results, the PhrA protein is classified as a class I, HDF-type, CPD DNA photolyase. 相似文献
99.
Salvador?Peiru Andres?Aguirre Florencia?Eberhardt Mauricio?Braia Rodolfo?Cabrera Hugo?G.?MenzellaEmail author 《Biotechnology for biofuels》2015,8(1):223
Background
Biodiesels produced from transesterification of vegetable oils have a major quality problem due to the presence of precipitates, which need to be removed to avoid clogging of filters and engine failures. These precipitates have been reported to be mostly composed of steryl glucosides (SGs), but so far industrial cost-effective methods to remove these compounds are not available. Here we describe a novel method for the efficient removal of SGs from biodiesel, based on the hydrolytic activity of a thermostable β-glycosidase obtained from Thermococcus litoralis.Results
A steryl glucosidase (SGase) enzyme from T. litoralis was produced and purified from Escherichia coli cultures expressing a synthetic gene, and used to treat soybean-derived biodiesel. Several optimization steps allowed for the selection of optimal reaction conditions to finally provide a simple and efficient process for the removal of SGs from crude biodiesel. The resulting biodiesel displayed filterability properties similar to distilled biodiesel according to the total contamination (TC), the cold soak filtration test (CSFT), filter blocking tendency (FBT), and cold soak filter blocking tendency (CSFBT) tests. The process was successfully scaled up to a 20 ton reactor, confirming its adaptability to industrial settings.Conclusions
The results presented in this work provide a novel path for the removal of steryl glucosides from biodiesel using a cost-effective, environmentally friendly and scalable enzymatic process, contributing to the adoption of this renewable fuel.100.
Anna Santoro Javier Conde Morena Scotece Vanessa Abella Ana Lois Veronica Lopez Jesus Pino Rodolfo Gomez Juan J. Gomez-Reino Oreste Gualillo 《PloS one》2015,10(8)