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1.
1. Individual blood samples from 144 Bali (Banteng) cattle [Bos (Bibos) javanicus] in the Northern Territory of Australia and from 61 Bali cross cattle, were examined by zone electrophoresis to determine the variants of haemoglobin, serum albumin and transferrin that are present. 2. Of the common cattle haemoglobin variants (A and B) only variant B occurs in the Bali cattle samples. A second variant, designated CBali, occurs in Bali cattle either as the heterozygote (B CBali) or as the homozygote, the frequencies of occurrence indicating a two-allele system of inheritance without dominance. The CBali cross samples may exhibit the homozygous or heterozygous A variant. 3. The CBali variant has an electrophoretic mobility intermediate between those of the A and B variants at pH 8.6 and 9.1 but closer to B than to A (B greater than C greater than A). It appears to be similar in mobility to the C variants found in Indian Khillan (CKhillan) by Naik, Sukumaran and Sanghvi (Anim. Prodn, 1965 I, 275-277), and in Asian cattle by Oishi, Abe and Namikama (Immunogenet. Lett., 1968 5, 170-173) and Abe, Mogi, Oishi, Tanaka and Suzuki (Proc. XIIth Europ. Conf. Anim. Blood Groups Biochem. Polymorphisms 1972, pp. 225-228), but appreciably different from those in Kenyan and Rhodesian cattle (CRhodesia) found by Braend (Anim. Blood Grps Biochem. Genet., 1971 2, 15-21) and Carr (Rhod. J. agric. Res., 1964 3, 62-62A), respectively. It is also different in mobility from the C variant found by Winter, Mayr, Schleger, Dworak, Krutzler and Burger (Res. vet. Sci., 1984 36, 276-283) in the mithun.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
2.
Insulin receptor substrate 1 (IRS-1) and IRS-2 are cytoplasmic adaptor proteins that mediate the activation of signaling pathways in response to ligand stimulation of upstream cell surface receptors. Despite sharing a high level of homology and the ability to activate PI3K, only Irs-2 positively regulates aerobic glycolysis in mammary tumor cells. To determine the contribution of Irs-2-dependent PI3K signaling to this selective regulation, we generated an Irs-2 mutant deficient in the recruitment of PI3K. We identified four tyrosine residues (Tyr-649, Tyr-671, Tyr-734, and Tyr-814) that are essential for the association of PI3K with Irs-2 and demonstrate that combined mutation of these tyrosines inhibits glucose uptake and lactate production, two measures of aerobic glycolysis. Irs-2-dependent activation of PI3K regulates the phosphorylation of specific Akt substrates, most notably glycogen synthase kinase 3β (Gsk-3β). Inhibition of Gsk-3β by Irs-2-dependent PI3K signaling promotes glucose uptake and aerobic glycolysis. The regulation of unique subsets of Akt substrates by Irs-1 and Irs-2 may explain their non-redundant roles in mammary tumor biology. Taken together, our study reveals a novel mechanism by which Irs-2 signaling preferentially regulates tumor cell metabolism and adds to our understanding of how this adaptor protein contributes to breast cancer progression.  相似文献   
3.
Altered protein expression and phosphorylation are common events during malignant transformation. These perturbations have been widely explored in the context of E-cadherin cell-cell adhesion complexes, which are central in the maintenance of the normal epithelial phenotype. A major component of these complexes is p120 catenin (p120), which binds and stabilizes E-cadherin to promote its adhesive and tumor suppressing function. However, p120 is also an essential mediator of pro-tumorigenic signals driven by oncogenes, such as Src, and can be phosphorylated at multiple sites. Although alterations in p120 expression have been extensively studied by immunohistochemistry (IHC) in the context of tumor progression, little is known about the status and role of p120 phosphorylation in cancer. Here we show that tyrosine and threonine phosphorylation of p120 in two sites, Y228 and T916, is elevated in renal and breast tumor tissue samples. We also show that tyrosine phosphorylation of p120 at its N-terminus, including at the Y228 site is required for its pro-tumorigenic potential. In contrast, phosphorylation of p120 at T916 does not affect this p120 function. However, phosphorylation of p120 at T916 interferes with epitope recognition of the most commonly used p120 antibody, namely pp120. As a result, this antibody selectively underrepresents p120 levels in tumor tissues, where p120 is phosphorylated. Overall, our data support a role of p120 phosphorylation as a marker and mediator of tumor transformation. Importantly, they also argue that the level and localization of p120 in human cancer tissues immunostained with pp120 needs to be re-evaluated.  相似文献   
4.
Studies of the energy return on investment (EROI) for oil production generally rely on aggregated statistics for large regions or countries. In order to better understand the drivers of the energy productivity of oil production, we use a novel approach that applies a detailed field-level engineering model of oil and gas production to estimate energy requirements of drilling, producing, processing, and transporting crude oil. We examine 40 global oilfields, utilizing detailed data for each field from hundreds of technical and scientific data sources. Resulting net energy return (NER) ratios for studied oil fields range from ≈2 to ≈100 MJ crude oil produced per MJ of total fuels consumed. External energy return (EER) ratios, which compare energy produced to energy consumed from external sources, exceed 1000:1 for fields that are largely self-sufficient. The lowest energy returns are found to come from thermally-enhanced oil recovery technologies. Results are generally insensitive to reasonable ranges of assumptions explored in sensitivity analysis. Fields with very large associated gas production are sensitive to assumptions about surface fluids processing due to the shifts in energy consumed under different gas treatment configurations. This model does not currently include energy invested in building oilfield capital equipment (e.g., drilling rigs), nor does it include other indirect energy uses such as labor or services.  相似文献   
5.
Abstract Burkholderia cepacia has emerged as an important multiresistant pathogen in cystic fibrosis (CF), associated in 20% of colonised patients with a rapid and fatal decline in lung function. Although knowledge of B. cepacia epidemiology has improved, the mechanisms involved in pathogenesis remain obscure. In this study, B. cepacia lipopolysaccharide (LPS) was assessed for endotoxic potential and the capacity to induce tumour necrosis factor (TNF). LPS preparations from clinical and environmental isolates of B. cepacia and from the closely related species Burkholderia gladioli exhibited a higher endotoxic activity and more pronounced cytokine response in vitro compared to preparations from the major CF pathogen Pseudomonas aeruginosa . This study may help to explain the vicious host immune response observed during pulmonary exacerbations in CF patients colonised by B. cepacia and lead to therapeutic advances in clinical management.  相似文献   
6.
The synthesis of the enantiomers of 2,2-difluoro-2-deoxy-myo-inositol 1,4,5-trisphosphate is reported. L-2,2-difluoro-2-deoxy-myo-inositol 1,4,5-trisphosphate is a potent inhibitor of 3-kinase and 5-phosphatase.  相似文献   
7.
The meander tail mouse harbors a recessive mutation on chromosome 4 that affects the anterior lobes of the cerebellum and the caudal vertebrae. Examination of the mea/mea cerebellum reveals that the complete disorganization of all cell types seen in the anterior lobes is separated by a sharp and consistent boundary from the normal cytoarchitecture of the posterior lobes. In the absence of any biochemical information regarding the affected gene product, attempts to clone the gene must rely on the strategy of reverse genetics. As an initial step in this process we have constructed a genetic linkage map spanning 68 cM of chromosome 4 using an intersubspecific phenotypic backcross. The loci included in this analysis are Calb, Ggtb, Lv, b, Ifa, mea, D4Rp1, Glut-1, Lck, Lmyc-1, and Eno-1. This analysis positions the mea phenotypic locus in the interval between Ifa and Glut1. These results also further define regions of homology between mouse chromosome 4 and human chromosomes 8, 1, and 9. This linkage map provides the means to evaluate candidate genes, and to identify tightly linked markers useful for cloning the meander tail locus.  相似文献   
8.
9.
Zaldivar‐River ó n, A., Areekul, B., Shaw, M. R. & Quicke, D. L. J. (2004). Comparative morphology of the venom apparatus in the braconid wasp subfamily Rogadinae (Insecta, Hymenoptera, Braconidae) and related taxa. —Zoologica Scripta, 33, 223–237. The morphology of the venom apparatus intima in representatives of 38 genera of the problematic braconid wasp subfamily Rogadinae and other cyclostome braconids was investigated and a preliminary phylogenetic analysis for the group was performed with the information obtained. Despite the limited number of characters, the data suggest several relationships at various taxonomic levels. The venom apparatus in the Clinocentrini and the Stiropiini is relatively unmodified and similar to that found in other genera previously placed within a broader concept of the Rogadinae (e.g. genera of Lysitermini, Pentatermini, Tetratermini, Hormiini) and also to that of the Betylobraconinae. The presence of a cone of filaments located inside the secondary venom duct near to its insertion on the venom reservoir/primary venom duct is proposed as a synapomorphy for the tribe Rogadini to the exclusion of Stiropiini, Clinocentrini and Yeliconini. Other features of the secondary venom duct and its insertion on the venom reservoir/primary venom duct support a number of relationships between the genera of the Rogadini and also within the large genus Aleiodes. A clade containing 15 Rogadini genera (Bathoteca, Bathotecoides, Bulborogas, Canalirogas, Colastomion, Conspinaria, Cystomastacoides, Macrostomion, Megarhogas, Myocron, Pholichora, Rectivena, Rogas, Spinaria and Triraphis) is supported by the presence of a thickened and short secondary venom duct, whereas the different members of Aleiodes (excluding members of the subgenus Heterogamus) and Cordylorhogas are distinguished by having a recessed secondary venom duct with well‐defined and numerous internal filaments. New World Rogas species exhibit a unique venom apparatus and may not be closely related to the Old World ones. Features of the venom apparatus of the enigmatic genus Telengaia and the exothecine genera Shawiana and Colastes suggest that the Telengainae and Exothecinae are both closely related to the Braconinae, Gnamptodontinae, and possibly to the Opiinae and Alysiinae. An unsculptured venom reservoir was found in one specimen of the type species of Avga, A. choaspes, which is consistent with it occupying either a very basal position within the cyclostome braconids or belonging to a recently recognized ‘Gondwanan’ clade that also includes the Aphidiinae.  相似文献   
10.
Pycnogenol® (PYC), a patented combination of bioflavonoids extracted from the bark of French maritime pine (Pinus maritima), scavenges free radicals and promotes cellular health. The protective capacity of PYC against ethanol toxicity of neurons has not previously been explored. The present study demonstrates that in postnatal day 9 (P9) rat cerebellar granule cells the antioxidants vitamin E (VE) and PYC (1) dose dependently block cell death following 400, 800, and 1600 mg/dL ethanol exposure (2) inhibit the ethanol‐induced activation of caspase‐3 in the same model system; and (3) reduce neuronal membrane disruption as assayed by phosphatidylserine translocation to the cell surface. These results suggest that both PYC and VE have the potential to act as therapeutic agents, antagonizing the induction of neuronal cell death by ethanol exposure. © 2004 Wiley Periodicals, Inc. J Neurobiol 59: 261–271, 2004  相似文献   
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