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71.
Using small-angle x-ray scattering (SAXS), we investigated the phase behavior of mesophases of monoolein (MO) mixed with additives commonly used for the crystallization of membrane proteins from lipidic mesophases. In particular, we examined the effect of sodium and potassium phosphate salts and the detergent β-octylglucoside (βOG) over a wide range of compositions relevant for the crystallization of membrane proteins in lipidic mesophases. We studied two types of systems: 1), ternary mixtures of MO with salt solutions above the hydration boundary; and 2), quaternary mixtures of MO with βOG and salt solutions over a wide range of hydration conditions. All quaternary mixtures showed highly regular lyotropic phase behavior with the same sequence of phases (Lα, Ia3d, and Pn3m) as MO/water mixtures at similar temperatures. The effects of additives in quaternary systems agreed qualitatively with those found in ternary mixtures in which only one additive is present. However, quantitative differences in the effects of additives on the lattice parameters of fully hydrated mesophases were found between ternary and quaternary mixtures. We discuss the implications of these findings for mechanistic investigations of membrane protein crystallization in lipidic mesophases and for studies of the suitability of precipitants for mesophase-based crystallization methods.  相似文献   
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Highlights? A proteomic method identifies protein-protein interaction in primary tumors ? GREB1 is the top estrogen-induced ER-interacting protein ? GREB1 is an essential ER cofactor recruited to chromatin ? GREB1 is an independent prognostic marker  相似文献   
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Shoot fly is a major insect pest of sorghum damaging early crop growth, establishment and productivity. Host plant resistance is an efficient approach to minimize yield losses due to shoot fly infestation. Seedling leaf blade glossiness and trichome density are morphological traits associated with shoot fly resistance. Our objective was to identify and evaluate QTLs for glossiness and trichome density using- i) 1894 F2s, ii) a sub-set of 369 F2-recombinants, and iii) their derived 369 F2:3 progenies, from a cross involving introgression lines RSG04008-6 (susceptible)?×?J2614-11 (resistant). The QTLs were mapped to a 37–72 centimorgan (cM) or 5–15 Mb interval on the long arm of sorghum chromosome 10 (SBI-10L) with flanking markers Xgap001 and Xtxp141. One QTL each for glossiness (QGls10) and trichome density (QTd10) were mapped in marker interval Xgap001-Xnhsbm1044 and Xisep0630-Xtxp141, confirming their loose linkage, for which phenotypic variation accounted for ranged from 2.29 to 11.37 % and LOD values ranged from 2.03 to 24.13, respectively. Average physical map positions for glossiness and trichome density QTLs on SBI-10 from earlier studies were 4 and 2 Mb, which in the present study were reduced to 2 Mb and 800 kb, respectively. Candidate genes Glossy15 (Sb10g025053) and ethylene zinc finger protein (Sb10g027550) falling in support intervals for glossiness and trichome density QTLs, respectively, are discussed. Also we identified a sub-set of recombinant population that will facilitate further fine mapping of the leaf blade glossiness and trichome density QTLs on SBI-10.  相似文献   
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BackgroundThere is limited evidence on the costs of Endometrial Cancer (EC) by stage of disease. We estimated the long-term secondary care costs of EC according to stage at diagnosis in an English population-based cohort.MethodsWomen participating in UKCTOCS and diagnosed with EC following enrolment (2001–2005) and prior to 31st Dec 2009 were identified to have EC through multiple sources. Survival was calculated through data linkage to death registry. Costs estimates were derived from hospital records accessed from Hospital Episode Statistics (HES) with additional patient level covariates derived from case notes and patient questionnaires. Missing and censored data was imputed using Multiple Imputation. Regression analysis of cost and survival was undertaken.Results491 of 641 women with EC were included. Five year total costs were strongly dependent on stage, ranging from £9,475 (diagnosis at stage IA/IB) to £26,080 (diagnosis at stage III). Stage, grade and BMI were the strongest predictors of costs. The majority of costs for stage I/II EC were incurred in the first six months after diagnosis while for stage III / IV considerable costs accrued after the first six months.ConclusionsIn addition to survival advantages, there are significant cost savings if patients with EC are detected earlier.  相似文献   
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Adequate utilization of services is critical to maximize the impact of counselling on infant and young child feeding (IYCF), but little is known about factors affecting utilization. Our study examined supply- and demand-side factors associated with the utilization of IYCF counselling services in Viet Nam. We used survey data from mothers with children <2y (n = 1,008) and health staff (n = 60) from the evaluation of a program that embedded IYCF counseling into the existing government health system. The frequency of never users, one-time users, repeat users, and achievers of the recommended minimum number of visits at health facilities were 45.1%, 13.0%, 28.4% and 13.5%, respectively. Poisson regression showed that demand-generation strategies, especially invitation cards, were the key factors determining one-time use (Prevalence ratio, PR 3.0, 95% CI: 2.2–4.2), repeated use (PR 3.2, 95% CI: 2.4–4.2), and achievement of minimum visits (PR 5.5, 95% CI: 3.6–8.4). Higher maternal education was associated with higher utilization both for one-time and repeated use. Being a farmer, belonging to an ethnic minority, and having a wasted child were associated with greater likelihood of achieving the minimum recommended number of visits, whereas child stunting or illness were not. Distance to health center was a barrier to repeated visits. Among supply-side factors, good counselling skills (PR: 1.3–1.8) was the most important factor associated with any service use, whereas longer employment duration and greater work pressure of health center staff were associated with lower utilization. Population attributable risk estimations showed that an additional 25% of the population would have achieved the minimum number of visits if exposed to three demand-generation strategies, and further increased to 49% if the health staff had good counseling skills and low work pressure. Our study provides evidence that demand-generation strategies are essential to increase utilization of facility-based IYCF counselling services in Viet Nam, and may be relevant for increasing and sustaining use of nutrition services in similar contexts.  相似文献   
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Context: Asenapine maleate (ASPM) is an antipsychotic drug for the treatment of schizophrenia and bipolar disorder. Extensive metabolism makes the oral route inconvenient for ASPM.

Objective: The objective of this study is to increase ASPM bioavailability via transdermal route by improving the skin permeation using combined strategy of chemical and nano-carrier (transfersomal) based approaches.

Materials and methods: Transfersomes were prepared by the thin film hydration method using soy-phosphatidylcholine (SPC) and sodium deoxycholate (SDC). Transfersomes were characterized for particle size, polydispersity index (PDI), zeta potential (ZP), entrapment efficiency, surface morphology, and in vitro skin permeation studies. Various chemical enhancers were screened for skin permeation enhancement of ASPM. Optimized transfersomes were incorporated into a gel base containing suitable chemical enhancer for efficient transdermal delivery. In vivo pharmacokinetic study was performed in rats to assess bioavailability by transdermal route against oral administration.

Results and discussion: Optimized transfersomes with drug:SPC:SDC weight ratio of 5:75:10 were spherical with an average size of 126.0?nm, PDI of 0.232, ZP of??43.7?mV, and entrapment efficiency of 54.96%. Ethanol (20% v/v) showed greater skin permeation enhancement. The cumulative amount of ASPM permeated after 24?h (Q24) by individual effect of ethanol and transfersome, and in combination was found to be 160.0, 132.9, and 309.3?μg, respectively, indicating beneficial synergistic effect of combined approach. In vivo pharmacokinetic study revealed significant (p?Conclusion: Dual strategy of permeation enhancement was successful in increasing the transdermal permeation and bioavailability of ASPM.  相似文献   
79.
Human Dual-specificity tyrosine (Y) Regulated Kinase 1A (DYRK1A) is encoded by a dosage dependent gene whereby either trisomy or haploinsufficiency result in developmental abnormalities. However, the function and regulation of this important protein kinase are not fully understood. Here, we report proteomic analysis of DYRK1A in human cells that revealed a novel role of DYRK1A in DNA double-strand breaks (DSBs) repair, mediated in part by its interaction with the ubiquitin-binding protein RNF169 that accumulates at the DSB sites and promotes homologous recombination repair (HRR) by displacing 53BP1, a key mediator of non-homologous end joining (NHEJ). We found that overexpression of active, but not the kinase inactive DYRK1A in U-2 OS cells inhibits accumulation of 53BP1 at the DSB sites in the RNF169-dependent manner. DYRK1A phosphorylates RNF169 at two sites that influence its ability to displace 53BP1 from the DSBs. Although DYRK1A is not required for the recruitment of RNF169 to the DSB sites and 53BP1 displacement, inhibition of DYRK1A or mutation of the DYRK1A phosphorylation sites in RNF169 decreases its ability to block accumulation of 53BP1 at the DSB sites. Interestingly, CRISPR-Cas9 knockout of DYRK1A in human and mouse cells also diminished the 53BP1 DSB recruitment in a manner that did not require RNF169, suggesting that dosage of DYRK1A can influence the DNA repair processes through both RNF169-dependent and independent mechanisms. Human U-2 OS cells devoid of DYRK1A display an increased HRR efficiency and resistance to DNA damage, therefore our findings implicate DYRK1A in the DNA repair processes.  相似文献   
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