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81.
A 17 bp deletion in the Bone Morphogenetic Protein 15 (BMP15) gene is associated to increased prolificacy in the Rasa Aragonesa sheep breed 总被引:2,自引:0,他引:2
Monteagudo LV Ponz R Tejedor MT Laviña A Sierra I 《Animal reproduction science》2009,110(1-2):139-146
Different mutations in the Bone Morphogenetic Protein 15 (BMP15) and the Growth Differentiation Factor 9 (GDF9) genes cause increased ovulation rate and infertility in a dosage-sensitive manner in sheep. They cause increased ovulation rate and twin and triplet births in heterozygotes, and complete primary ovarian failure in homozygotes resulting in total infertility. We are here presenting a novel mutation in the second exon of the ovine BMP15 gene, found in the Spanish breed Rasa Aragonesa. It consists of a 17 bp deletion resulting in displacement of the open reading frame and premature stop codons. As a consequence, nearly 85% of the sequence of the wild type aminoacidic chain in the second exon of the BMP15 pro-protein is modified or suppressed as only the first 45 amino acids are conserved of the 245 original. The mature peptide is lost. The ewes heterozygous for this deletion present very high prolificacy (2.66 lambs/birth) when compared to a mean flock prolificacy of 1.36 lambs. The deletion causes a complete lack of functionality of the second exon of BMP15, comparable to the effect of premature stop codons in other mutations. Therefore, homozygous females for the deletion are expected to present primary ovarian failure. DNA sequence analysis of the GDF9 coding regions detected only a synonymous Single Nucleotide Polymorphism (SNP), apparently not linked to changes in prolificacy. 相似文献
82.
Short‐term lime pretreatment uses lime and high‐pressure oxygen to significantly increase the digestibility of poplar wood. When the treated poplar wood was enzymatically hydrolyzed, glucan and xylan were converted to glucose and xylose, respectively. To calculate product yields from raw biomass, these sugars were expressed as equivalent glucan and xylan. To recommend pretreatment conditions, the single criterion was the maximum overall glucan and xylan yields using a cellulase loading of 15 FPU/g glucan in raw biomass. On this basis, the recommended conditions for short‐term lime pretreatment of poplar wood follow: (1) 2 h, 140°C, 21.7 bar absolute and (2) 2 h, 160°C, and 14.8 bar absolute. In these two cases, the reactivity was nearly identical, thus the selected condition depends on the economic trade off between pressure and temperature. Considering glucose and xylose and their oligomers produced during 72 h of enzymatic hydrolysis, the overall yields attained under these recommended conditions follow: (1) 95.5 g glucan/100 g of glucan in raw biomass and 73.1 g xylan/100 g xylan in raw biomass and (2) 94.2 g glucan/100 g glucan in raw biomass and 73.2 g xylan/100 g xylan in raw biomass. The yields improved by increasing the enzyme loading. An optimal enzyme cocktail was identified as 67% cellulase, 12% β‐glucosidase, and 24% xylanase (mass of protein basis) with cellulase activity of 15 FPU/g glucan in raw biomass and total enzyme loading of 51 mg protein/g glucan in raw biomass. Ball milling the lime‐treated poplar wood allowed for 100% conversion of glucan in 120 h with a cellulase loading of only 10 FPU/g glucan in raw biomass. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2009 相似文献
83.
Emily HM Wong David K Smith Raul Rabadan Malik Peiris Leo LM Poon 《BMC evolutionary biology》2010,10(1):253
Background
The influenza A virus is an important infectious cause of morbidity and mortality in humans and was responsible for 3 pandemics in the 20th century. As the replication of the influenza virus is based on its host's machinery, codon usage of its viral genes might be subject to host selection pressures, especially after interspecies transmission. A better understanding of viral evolution and host adaptive responses might help control this disease. 相似文献84.
Background
Administration of psychomotor stimulants like amphetamine facilitates behavior in the presence of incentive distal stimuli, which have acquired the motivational properties of primary rewards through associative learning. This facilitation appears to be mediated by the mesolimbic dopamine system, which may also be involved in facilitating behavior in the presence of distal stimuli that have not been previously paired with primary rewards. However, it is unclear whether psychomotor stimulants facilitate behavioral interaction with unconditioned distal stimuli.Principal Findings
We found that noncontingent administration of amphetamine into subregions of the rat ventral striatum, particularly in the vicinity of the medial olfactory tubercle, facilitates lever pressing followed by visual signals that had not been paired with primary rewards. Noncontingent administration of amphetamine failed to facilitate lever pressing when it was followed by either tones or delayed presentation or absence of visual signals, suggesting that visual signals are key for enhanced behavioral interaction. Systemic administration of amphetamine markedly increased locomotor activity, but did not necessarily increase lever pressing rewarded by visual signals, suggesting that lever pressing is not a byproduct of heightened locomotor activity. Lever pressing facilitated by amphetamine was reduced by co-administration of the dopamine receptor antagonists SCH 23390 (D1 selective) or sulpiride (D2 selective).Conclusions
Our results suggest that amphetamine administration into the ventral striatum, particularly in the vicinity of the medial olfactory tubercle, activates dopaminergic mechanisms that strongly enhance behavioral interaction with unconditioned visual stimuli. 相似文献85.
86.
Martínez-Lorenzo MJ Anel A Monleón I Sierra JJ Piñeiro A Naval J Alava MA 《The international journal of biochemistry & cell biology》2000,32(4):435-445
A prominent tyrosine phosphorylated protein of 85 kDa (p85) was detected in highly proliferative sublines derived from the Jurkat T cell leukemia. We undertook a study to characterize the identity of this protein and its possible role in the hyperproliferative phenotypes observed. Using immunoblot and immunoprecipitation techniques, this protein was characterized as the p85 regulatory subunit of phosphatidylinositol 3-kinase. Cell proliferation and p85 tyrosine phosphorylation was not affected by tyrphostin AG-490, an inhibitor of Jak kinases, wortmannin or LY294002, inhibitors of the activity of the catalytic phosphatidylinositol 3-kinase subunit. Herbimycin-A and PPI, inhibitors of src-like protein tyrosine kinases, and genistein, a general tyrosine kinase inhibitor, inhibited p85 tyrosine phosphorylation and induced cell death in the sublines. PD98059, an inhibitor of Mek, inhibited cell growth of the sublines, but not that of the parental cells. It was concluded that tyrosine phosphorylation of p85 is associated with highly proliferative tumoral phenotypes, at least in T cell leukemias, independent of the phosphatidylinositol 3-kinase activity of the catalytic subunit. 相似文献
87.
88.
Melero M Rubio-Guerri C Crespo JL Arbelo M Vela AI García-Párraga D Sierra E Domínguez L Sánchez-Vizcaíno JM 《Diseases of aquatic organisms》2011,97(2):167-170
An adult female bottlenose dolphin (Tursiops truncatus) stranded alive and subsequently died several minutes later on the Mediterranean coast of Spain on 14 July 2010. Clinical examination revealed foam through the blowhole and rales upon lung auscultation. On venipuncture, the blood was abnormally dense and dark. Hematological and biochemical abnormalities included dehydration, leukocytosis (48 600 leukocytes microl(-1)) characterized by neutrophilia (48 200 neutrophils microl(-1)), and elevated bilirubin (4.38 mg dl(-1)), alanine aminotransferase (382.3 U l(-1)), aspartate aminotransferase (1449.3 U l(-1)), lactate dehydrogenase (1631.3 U l(-1)), and creatine kinase (404.7 U l(-1)). The most relevant findings of the gross examination were rhomboid-shaped skin lesions, stable froth in the trachea, pulmonary congestion, abnormally thick and rough pleura with adhesions, edematous and congestive superficial cervical and tracheobronchial lymph nodes, red-tinged urine, and severe brain congestion. Histopathology of the kidney, lung, skin, and brain revealed multisystemic intravascular bacterial emboli. Samples of skin, brain, and lung were cultured on Columbia blood agar under both aerobic and anaerobic conditions, and pure and heavy bacterial cultures were obtained from skin and brain samples. The microorganism isolated was Gram-positive, catalase-negative, facultatively anaerobic, and rod-shaped. The isolates were identified as Erysipelothrix rhusiopathiae by the API Coryne biochemical system. Based on the gross and microscopic findings, a diagnosis of acute E. rhusiopathiae septicemia was made. To the best of our knowledge, this is the first report of E. rhusiopathiae septicemia in a free-ranging bottlenose dolphin. 相似文献
89.
Arnó M Betancur-Galvis L González MA Sierra J Zaragozá RJ 《Bioorganic & medicinal chemistry》2003,11(14):3171-3177
Based on two lead cytotoxic spongiane diterpenes, a new series of C7-oxygenated derivatives were synthesized and evaluated for their antitumor activity in vitro against the cancer cell lines HeLa and HEp-2. In general, introduction of either hydroxyl or acetoxy groups at C-7 did not improve the resultant cytotoxicity, while the presence of a butyrate ester led to more active compounds (CC(50)=4.0-9.5 microM). 相似文献
90.
Rebecca C Mueller Fabiana S Paula Babur S Mirza Jorge LM Rodrigues Klaus Nüsslein Brendan JM Bohannan 《The ISME journal》2014,8(7):1548-1550
Understanding the interactions among microbial communities, plant communities and soil properties following deforestation could provide insights into the long-term effects of land-use change on ecosystem functions, and may help identify approaches that promote the recovery of degraded sites. We combined high-throughput sequencing of fungal rDNA and molecular barcoding of plant roots to estimate fungal and plant community composition in soil sampled across a chronosequence of deforestation. We found significant effects of land-use change on fungal community composition, which was more closely correlated to plant community composition than to changes in soil properties or geographic distance, providing evidence for strong links between above- and below-ground communities in tropical forests. 相似文献