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51.
Development of the neurovascular unit (NVU) is a complex, multistage process that requires orchestrated cell signaling mechanisms across several cell types and ultimately results in formation of the blood-brain barrier. Typical high-throughput screening (HTS) assays investigate single biochemical or single cell responses following chemical insult. As the NVU comprises multiple cell types interacting at various stages of development, a methodology combining high-throughput results across pertinent cell-based assays is needed to investigate potential chemical-induced disruption to the development of this complex cell system. To this end, we implemented a novel method for screening putative NVU disruptors across diverse assay platforms to predict chemical perturbation of the developing NVU. HTS assay results measuring chemical-induced perturbations to cellular key events across angiogenic and neurogenic outcomes in vitro were combined to create a cell-based prioritization of NVU hazard. Chemicals were grouped according to similar modes of action to train a logistic regression literature model on a training set of 38 chemicals. This model utilizes the chemical-specific pairwise mutual information score for PubMed MeSH annotations to represent a quantitative measure of previously published results. Taken together, this study presents a methodology to investigate NVU developmental hazard using cell-based HTS assays and literature evidence to prioritize screening of putative NVU disruptors towards a knowledge-driven characterization of neurovascular developmental toxicity. The results from these screening efforts demonstrate that chemicals representing a range of putative vascular disrupting compound (pVDC) scores can also produce effects on neurogenic outcomes and characterizes possible modes of action for disrupting the developing NVU.  相似文献   
52.
Chemical exchange saturation transfer (CEST) MRI is sensitive to labile proton concentration and exchange rate, thus allowing measurement of dilute CEST agent and microenvironmental properties. However, CEST measurement depends not only on the CEST agent properties but also on the experimental conditions. Quantitative CEST (qCEST) analysis has been proposed to address the limitation of the commonly used simplistic CEST‐weighted calculation. Recent research has shown that the concomitant direct RF saturation (spillover) effect can be corrected using an inverse CEST ratio calculation. We postulated that a simplified qCEST analysis is feasible with omega plot analysis of the inverse CEST asymmetry calculation. Specifically, simulations showed that the numerically derived labile proton ratio and exchange rate were in good agreement with input values. In addition, the qCEST analysis was confirmed experimentally in a phantom with concurrent variation in CEST agent concentration and pH. Also, we demonstrated that the derived labile proton ratio increased linearly with creatine concentration (P < 0.01) while the pH‐dependent exchange rate followed a dominantly base‐catalyzed exchange relationship (P < 0.01). In summary, our study verified that a simplified qCEST analysis can simultaneously determine labile proton ratio and exchange rate in a relatively complex in vitro CEST system. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
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54.
The challenges of conducting surgical oncology trials have resulted to low quantity and poor quality research [1,2]. Considering the definitive role of surgery to offer cure, immediate response to improve surgical research is needed [3]. The European Organization for Research and Treatment of Cancer (EORTC) and the European Society of Surgical Oncology (ESSO) share the vision to achieve excellent surgical research and care for cancer patients. Building on their complimentary expertise, they embarked on a pilot project to map out challenges and initiate a sustainable collaboration to advance cancer surgery research in Europe. This pilot project is EORTC-ESSO 1409 GITCG/ ESSO-01: A Prospective Colorectal Liver Metastasis Database with an Integrated Quality Assurance Program (CLIMB). This article will describe the challenges, milestones and vision of both organizations in setting up this collaboration.  相似文献   
55.
《The ocular surface》2019,17(1):60-63
PurposeTo characterize vision-related and psychosocial quality of life (QoL) parameters in medically and surgically treated patients with OSSN.MethodsForty-one patients with OSSN treated with medical therapy consisting of interferon alpha 2b drops 1 MIU/ml (n = 22) or who underwent surgical excision (n = 19) were contacted. All subjects answered a quality of life assessment with an original questionnaire in which they were asked about a range of parameters. Overall satisfaction and motivating factors for treatment were also reviewed.ResultsThe mean age at the time of the survey was 64.6 and 51% were male with similar demographics between groups. Based on the previous cohort, rates of tumor resolution and recurrences were comparable in the two groups. Reasons for choosing a particular treatment varied between the groups. Forty percent of individuals in the medical group reported a fear of surgery (p = 0.03) and often made the decision after personal research (p = 0.008). Thirty-two percent of patients in the surgical group chose surgery due to fear of decreased vision due to lesion growth, therefore wanting immediate resolution (p = 0.09). Drops precipitated more ocular symptoms such as tearing and itchiness, on the other hand, patients who had surgery reported having more pain.ConclusionQuality of life considerations before, during, and after OSSN treatment is an important yet understudied topic. Our study is the first to look at QoL parameters in OSSN treatment and we found that patients in both medically and surgically treated groups had similar QoL metric but were driven to choose chemotherapy due to fear of surgery and/or prior literature review.  相似文献   
56.
IntroductionNumerous techniques have been proposed for the plastic surgical treatment of hypertrophic breasts. Challenges of the procedure include the preservation of vascular supply and sensitivity of the nipple areola complex (NAC), breast feeding, and an esthetically pleasing result.ObjectivesIn the present preliminary report, we introduce a new technique called the three-block L-wing reduction mammaplasty that addresses the aforementioned difficulties.Materials and MethodsThe three-block L-wing reduction mammaplasty with a thick hemispheric superiorly based NAC pedicle and a medial as well as lateral pillar was performed in a total of 60 patients.ResultsOur technique increases both, vascular safety and the sensory supply to the NAC, as it conceptually decreases the need for dissection of breast tissue and skin. The incidence of fat necrosis and wound healing disorders may be reduced with this technique. Because the ducts of the breast-gland underneath the NAC are not dissected, this technique also promises a higher probability of regular breast-feeding. Finally, our technique permits a cosmetically pleasing round-shaped mound of the breast.ConclusionThe three-block modification simplifies the procedure of the superior pedicle L-wing mammaplasty markedly. It may increase the esthetic as well as the functional outcome and decrease postoperative complications.  相似文献   
57.
IntroductionDural puncture epidural (DPE) analgesia is a modification of conventional epidural analgesia that involves the intentional puncture of the dura with a spinal needle through the needle placed in the epidural space, without a medication being injected intrathecally. There have been contradictory findings regarding better analgesia and better block quality.MethodsA systematic literature search was done to identify randomized controlled trials (RCT) comparing DPE with epidural analgesia. The risk of bias was assessed with the Cochrane tool. Risk ratio and 95% confidence intervals were calculated.ResultsFive RCTs including 581 patients were identified. One RCT on caesarean section was excluded. Single studies suggested slightly better analgesia by finding a median time to achieve sufficient analgesia of two minutes less in the DPE group, a higher number of women having a pain score <10/100 at 20 min, a reduction in the number of epidural top-ups and better sacral spread. The studies did not show a difference between DPE and epidural analgesia for catheter replacement or manipulation rates, the incidence of intravascular placement or unilateral block.ConclusionThere is a lack of clear evidence on either the benefits or the risks of the DPE technique, such that a recommendation for or against its routine use is premature. Two of the three studies showing a beneficial effect of DPE came from the same institution and replication of the findings by other groups is warranted.  相似文献   
58.
This paper presents theoretical results on the convergence and attractivity of memristor-based cellular neural networks (MCNNs) with time delays. Based on a realistic memristor model, an MCNN is modeled using a differential inclusion. The essential boundedness of its global solutions is proven. The state of MCNNs is further proven to be convergent to a critical-point set located in saturated region of the activation function, when the initial state locates in a saturated region. It is shown that the state convergence time period is finite and can be quantitatively estimated using given parameters. Furthermore, the positive invariance and attractivity of state in non-saturated regions are also proven. The simulation results of several numerical examples are provided to substantiate the results.  相似文献   
59.
Many studies have reported age-associated DNA methylation changes and age-predictive models in various tissues and body fluids. Although age-associated DNA methylation changes can be tissue-specific, a multi-tissue age predictor that is applicable to various tissues and body fluids with considerable prediction accuracy might be valuable. In this study, DNA methylation at 5 CpG sites from the ELOVL2, FHL2, KLF14, C1orf132/MIR29B2C, and TRIM59 genes were investigated in 448 samples from blood, saliva, and buccal swabs. A multiplex methylation SNaPshot assay was developed to measure DNA methylation simultaneously at the 5 CpG sites. Among the 5 CpG sites, 3 CpG sites in the ELOVL2, KLF14 and TRIM59 genes demonstrated strong correlation between DNA methylation and age in all 3 sample types. Age prediction models built separately for each sample type using the DNA methylation values at the 5 CpG sites showed high prediction accuracy with a Mean Absolute Deviation from the chronological age (MAD) of 3.478 years in blood, 3.552 years in saliva and 4.293 years in buccal swab samples. A tissue-combined model constructed with 300 training samples including 100 samples from each blood, saliva and buccal swab samples demonstrated a very strong correlation between predicted and chronological ages (r = 0.937) and a high prediction accuracy with a MAD of 3.844 years in the 148 independent test set samples of 50 blood, 50 saliva and 48 buccal swab samples. Although more validation might be needed, the tissue-combined model’s prediction accuracies in each sample type were very much similar to those obtained from each tissue-specific model. The multiplex methylation SNaPshot assay and the age prediction models in our study would be useful in forensic analysis, which frequently involves DNA from blood, saliva, and buccal swab samples.  相似文献   
60.
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