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181.
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184.

Background  

CTCF (CCCTC-binding factor) is an evolutionarily conserved zinc finger protein involved in diverse functions ranging from negative regulation of MYC, to chromatin insulation of the beta-globin gene cluster, to imprinting of the Igf2 locus. The 11 zinc fingers of CTCF are known to differentially contribute to the CTCF-DNA interaction at different binding sites. It is possible that the differences in CTCF-DNA conformation at different binding sites underlie CTCF's functional diversity. If so, the CTCF binding sites may belong to distinct classes, each compatible with a specific functional role.  相似文献   
185.

Aim

To evaluate the associations of external beam radiation therapy (EBRT) and intracavitary brachytherapy (IB) with decreased sexual function.

Background

There’s inconsistent evidence on whether radiation for gynecologic cancers has an impact on sexual health. IB, an underutilized treatment modality, is thought to have less adverse effects than EBRT.

Materials and methods

A cross-sectional study examining decreased sexual function following radiation for gynecologic cancers. A decrease in sexual function was measured as a change in the Female Sexual Function Index (FSFI) from before to after treatment, with a significant decrease determined by Reliable Change Index Statistic (RCIS). Chi-square and t-tests were employed.

Results

171 women completed the survey; 35% (n?=?60) received radiation, of whom 29 received EBRT and IB (48%), 15 EBRT alone (25%), 16 IB alone (27%). Women who received radiation had similar rates of decreased sexual function as women who did not (47% vs. 38%, P?=?0.262). EBRT and IB had similar rates of decreased sexual function compared to women with no radiation (50% vs. 38% P?=?0.166 and 47% vs. 38% P?=?0.309). Women experiencing decreased sexual function were more likely to be under 50 years old (OR 5.4, 95%CI 1.6–18.1), have received chemotherapy (OR 5.7, 95%CI 1.4–22.9), and have cervical cancer (OR 7.8, 95%CI 2.1–28.8).

Conclusions

Treatment with EBRT or IB does not appear to impair sexual function in women with gynecologic cancer. Age less than 50, concurrent chemotherapy, and cervical cancer may place women with gynecologic cancer at higher risk for decreased sexual function following radiation.  相似文献   
186.
The accumulation of triacylglycerols (TAG) is a common feature among actinobacteria belonging to Rhodococcus genus. Some rhodococcal species are able to produce significant amounts of those lipids from different single substrates, such as glucose, gluconate or hexadecane. In this study we analyzed the ability of different species to produce lipids from olive oil mill wastes (OMW), and the possibility to enhance lipid production by genetic engineering. OMW base medium prepared from alperujo, which exhibited high values of chemical oxygen demand (127,000 mg/l) and C/N ratio (508), supported good growth and TAG production by some rhodococci. R. opacus, R. wratislaviensis and R. jostii were more efficient at producing cell biomass (2.2–2.7 g/l) and lipids (77–83% of CDW, 1.8–2.2 g/l) from OMW than R. fascians, R. erythropolis and R. equi (1.1–1.6 g/l of cell biomass and 7.1–14.0% of CDW, 0.1–0.2 g/l of lipids). Overexpression of a gene coding for a fatty acid importer in R. jostii RHA1 promoted an increase of 2.2 fold of cellular biomass value with a concomitant increase in lipids production during cultivation of cells in OMW. This study demonstrates that the bioconversion of OMW to microbial lipids is feasible using more robust rhodococal strains. The efficiency of this bioconversion can be significantly enhanced by engineering strategies.  相似文献   
187.
Cardiac dyssynchrony arises from conduction abnormalities during heart failure and worsens morbidity and mortality. Cardiac resynchronization therapy (CRT) re‐coordinates contraction using bi‐ventricular pacing, but the cellular and molecular mechanisms involved remain largely unknown. The aim is to determine how dyssynchronous heart failure (HFdys) alters the phospho‐proteome and how CRT interacts with this unique phospho‐proteome by analyzing Ser/Thr and Tyr phosphorylation. Phospho‐enriched myocardium from dog models of Control, HFdys, and CRT is analyzed via MS. There were 209 regulated phospho‐sites among 1761 identified sites. Compared to Con and CRT, HFdys is hyper‐phosphorylated and tyrosine phosphorylation is more likely to be involved in signaling that increased with HFdys and was exacerbated by CRT. For each regulated site, the most‐likely targeting‐kinase is predicted, and CK2 is highly specific for sites that are “fixed” by CRT, suggesting activation of CK2 signaling occurs in HFdys that is reversed by CRT, which is supported by western blot analysis. These data elucidate signaling networks and kinases that may be involved and deserve further study. Importantly, a possible role for CK2 modulation in CRT has been identified. This may be harnessed in the future therapeutically to compliment CRT, improving its clinical effects.  相似文献   
188.

Background

Evidence-based guidelines for the management of mild traumatic brain injury (mTBI) in the emergency department (ED) are now widely available, and yet, clinical practice remains inconsistent with the guidelines. The Neurotrauma Evidence Translation (NET) intervention was developed to increase the uptake of guideline recommendations and improve the management of minor head injury in Australian emergency departments (EDs). However, the adoption of this type of intervention typically entails an upfront investment that may or may not be fully offset by improvements in clinical practice, health outcomes and/or reductions in health service utilisation. The present study estimates the cost and cost-effectiveness of the NET intervention, as compared to the passive dissemination of the guideline, to evaluate whether any improvements in clinical practice or health outcomes due to the NET intervention can be obtained at an acceptable cost.

Methods and findings

Study setting: The NET cluster randomised controlled trial [ACTRN12612001286831]. Study sample: Seventeen EDs were randomised to the control condition and 14 to the intervention. One thousand nine hundred forty-three patients were included in the analysis of clinical practice outcomes (NET sample). A total of 343 patients from 14 control and 10 intervention EDs participated in follow-up interviews and were included in the analysis of patient-reported health outcomes (NET-Plus sample). Outcome measures: Appropriate post-traumatic amnesia (PTA) screening in the ED (primary outcome). Secondary clinical practice outcomes: provision of written information on discharge (INFO) and safe discharge (defined as CT scan appropriately provided plus PTA plus INFO). Secondary patient-reported, post-discharge health outcomes: anxiety (Hospital Anxiety and Depression Scale), post-concussive symptoms (Rivermead), and preference-based health-related quality of life (SF6D). Methods: Trial-based economic evaluations from a health sector perspective, with time horizons set to coincide with the final follow-up for the NET sample (2 months post-intervention) and to 1-month post-discharge for the NET-Plus sample. Results: Intervention and control groups were not significantly different in health service utilisation received in the ED/inpatient ward following the initial mTBI presentation (adjusted mean difference $23.86 per patient; 95%CI ??$106, $153; p?=?0.719) or over the longer follow-up in the NET-plus sample (adjusted mean difference $341.78 per patient; 95%CI ??$58, $742; p?=?0.094). Savings from lower health service utilisation are therefore unlikely to offset the significantly higher upfront cost of the intervention (mean difference $138.20 per patient; 95%CI $135, $141; p?<?0.000). Estimates of the net effect of the intervention on total cost (intervention cost net of health service utilisation) suggest that the intervention entails significantly higher costs than the control condition (adjusted mean difference $169.89 per patient; 95%CI $43, $297, p?=?0.009). This effect is larger in absolute magnitude over the longer follow-up in the NET-plus sample (adjusted mean difference $505.06; 95%CI $96, $915; p?=?0.016), mostly due to additional health service utilisation. For the primary outcome, the NET intervention is more costly and more effective than passive dissemination; entailing an additional cost of $1246 per additional patient appropriately screened for PTA ($169.89/0.1363; Fieller’s 95%CI $525, $2055). For NET to be considered cost-effective with 95% confidence, decision-makers would need to be willing to trade one quality-adjusted life year (QALY) for 25 additional patients appropriately screened for PTA. While these results reflect our best estimate of cost-effectiveness given the data, it is possible that a NET intervention that has been scaled and streamlined ready for wider roll-out may be more or less cost-effective than the NET intervention as delivered in the trial.

Conclusions

While the NET intervention does improve the management of mTBI in the ED, it also entails a significant increase in cost and—as delivered in the trial—is unlikely to be cost-effective at currently accepted funding thresholds. There may be a scope for a scaled-up and streamlined NET intervention to achieve a better balance between costs and outcomes.

Trial registration

Australian New Zealand Clinical Trials Registry ACTRN12612001286831, date registered 12 December 2012.
  相似文献   
189.
Among biomass-derived compounds, lignin is an underused component with potential for conversion to industrial-needed products in biorefinery. In this study, organosolv fractionation of four lignocellulosic materials including bagasse (BG), pararubber wood sawdust (PS), palm fiber (PF), and cassava fiber (CF) was studied using a ternary solvent mixture comprising methyl isobutyl ketone (MIBK), ethanol, and water in the presence of H2SO4 to separate high-purity lignin. The fractionation reaction was performed at 160 °C for 40 min with MIBK/ethanol/water proportion of 0.25/0.42/0.33 and 0.025 M of H2SO4, which led to the highest lignin removal efficiency of 88.2, 70.6, 67.3, and 71.7% (w/w) from BG, PS, PF, and CF, respectively. Physicochemical characteristics of the fractionated lignin were determined for Klason lignin and by X-ray fluorescence spectroscopy, organic elemental analysis, 1H nuclear magnetic resonance spectroscopy, and Fourier transform infrared spectroscopy. The lignin samples were thermally depolymerized in MIBK to determine the content of specific lignin-derived chemicals. The main phenolic derivatives from BG-lignin were 4-ethylphenol and 4-vinylguaiacol, whereas those from PS-lignin were syringaldehyde and cis-isoeugenol. Phenol and bis(2-ethylhexyl) phthalate were mainly produced from depolymerization of PF-lignin while trans-isoeugenol and hexadecanoic acid were the major products from CF-lignin. This work demonstrates the potential of the fractionated lignin for production of valuable chemicals in biorefineries.  相似文献   
190.
Autophagy mediates degradation and recycling of cellular components and plays an important role in senescence and adaptive responses to biotic and abiotic stresses. Nutrient deprivation has been shown to trigger triacylglycerol (TAG) accumulation and also induces autophagy in various green algae. However, the functional relationship between TAG metabolism and autophagy remains unclear. To gain preliminary evidence supporting a role of autophagy in TAG synthesis, Chlamydomonas reinhardtii CC-2686 was grown in Tris-acetate phosphate medium with or without nitrogen and treated with an autophagy inducer (rapamycin) or inhibitors (wortmannin, 3-methyladenine, and bafilomycin A1). Fluorescence microscopic analysis of Nile red-stained cells following 72-h treatments showed that rapamycin induced accumulation of subcellular lipid droplets which are storage sites of TAG. Rapamycin treatment in combination with nitrogen starvation led to a greater abundance of lipid droplets. Wortmannin and bafilomycin A1, but not 3-methyladenine, inhibited lipid droplet accumulation in rapamycin-treated cells and to a less extent in nitrogen-depleted cells. These results suggested that autophagy contributes to TAG synthesis in C. reinhardtii, but is not a necessary process. Autophagy induction may also be used to further enhance TAG accumulation in microalgae under nutrient deprivation.  相似文献   
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