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41.

Purpose

The aim of this study was to determine if the measurement of blood biomarkers of glucose cerebral metabolism, performed with retrograde jugular catheter, could predict the outcome of poor-grade aneurysmal subarachnoid hemorrhage (aSAH) patients.

Methods

This study was conducted in 68 poor-grade aSAH patients. A total of 4,024 blood samples obtained from jugular and radial catheters were analyzed for glucose, lactate, and oxygen content every 8 h for 10 ± 0.5 days. Metabolic ratio (MR) and lactate–oxygen index (LOI) were obtained by ratios using arterio-jugular differences. Functional outcome was evaluated at 12 months with the Glasgow Outcome Scale.

Results

Outcome was unfavorable in 40 patients. In this group of patients, the MR was significantly lower (p < 0.0001) and the LOI was significantly higher (p = 0.0001) than in the group with favorable outcome. The MR cutoff value, below which the patients are likely to have an unfavorable outcome, was determined to be 3.35. More interestingly, the data obtained in this study demonstrated that the patients achieving an unfavorable outcome were distinguished from those with a favorable outcome by having at least three events of MR inferior to 3.35 (sensitivity = 90 %, specificity = 82.1 %). Moreover, in patients who developed cerebral vasospasm, we observed a significant decrease in the MR.

Conclusion

Our data provide additional support to the view that the MR is a reliable marker for predicting the outcome of poor-grade aSAH patients. Prospective studies are needed to confirm its value in multimodal monitoring.  相似文献   
42.
Cell micropatterning was achieved in a spatially controlled manner based on heterogeneously wetted superhydrophilic/superhydrophobic diamond nanowire (NW) surfaces. Diamond NWs were synthesized on boron-doped diamond substrates using reactive ion etching and functionalized with octadecyltrichlorosilane to achieve superhydrophobicity. Superhydrophilic motifs of 400 × 400 μm2 and 10 × 10 μm2 single cell-sized motifs, surrounded by superhydrophobic regions, were then generated by selectively exposing the substrates to UV light. This design allowed successful patterning of single HeLa and MCF-10A cells within the superhydrophilic regions without additional surface modification. To add a further level of complexity, micropatterned co-cultures were obtained using bovine serum albumin to promote cell adhesion. This method is simple and does not require any complicated processing steps such as mask deposition or template removal. Potential applications are in the development of cell-based biological assays in well-controlled and biologically relevant environments.  相似文献   
43.

Objectives

Several epidemiological studies have revealed the co-occurrence of other autoimmune diseases (AIDs) within patients with systemic sclerosis (SSc). However, some of these studies were based on small cohorts and wide ranges of prevalence have been reported. Therefore to overcome these limitations of individual studies, we sought to perform a meta-analysis to determine the accurate prevalence of polyautoimmunity in SSc.

Methods

We performed a systematic review and a meta-analysis of literature in MEDLINE and Embase databases from January 1960 to March 2013. All cohort studies reporting on prevalence of other AIDs known to be associated with SSc were analyzed. Prevalence of polyautoimmunity and of each AID were then calculated.

Results

Ten studies reporting polyautoimmunity were identified corresponding to a total of 6102 SSc patients. Overall 1432 patients with at least one AID were identified corresponding to a weighted prevalence of polyautoimmunity equal to 25.7% CI 95% [20.1%–31.6%]. Overall 208/5139 SSc-patients had at least two additional AIDs resulting in a weighted prevalence of 3.9% [3.3%–4.4%]. The most prevalent associated AIDs were autoimmune thyroid disease (10.4%) followed by Sjögren's syndrome (7.7%) and dermatopolymyositis/polymyositis (5.6%).

Conclusion

Our results confirm that SSc polyautoimmunity is a frequent condition in SSc affecting a quarter of SSc-patients. The impact on the phenotype and also on the management and therapy will need to be addressed now in further works.  相似文献   
44.
Background and objectivesHuman fear conditioning is widely regarded as one of the prime paradigms for the study of fear and anxiety disorders. We provide an evaluation of a commonly used subjective measure in the human fear conditioning paradigm, namely the US-expectancy measurement.MethodsWe assess the validity of US-expectancy with respect to conditions of pathological fear and anxiety using four established criteria for scrutiny of a laboratory test or model (i.e., face validity, diagnostic validity, predictive validity, construct validity).ResultsArguably, there is sufficient evidence for the face validity, diagnostic validity, predictive validity and construct validity of the US-expectancy measure.LimitationsPresumed limitations of the US-expectancy measure, including its susceptibility to experimental demand and memory bias, are discussed.ConclusionsThe US-expectancy measure is a valuable measurement method that can be effectively used in research that aims to enhance our understanding of fear and anxiety disorders.  相似文献   
45.
ObjectiveThe thymus plays a crucial role in immune system homeostasis. Thymic abnormalities have been reported in many autoimmune diseases, but data for systemic sclerosis (SSc) and rheumatoid arthritis (RA) are sparse. The aim of this study was to evaluate the prevalence and correlates of radiological incomplete involution of the thymus in SSc and RA patients, and in a non-autoimmune group of controls.MethodsAll patients were at least 40 years old: 96 SSc patients (median age 59 years, 80% women) and 65 RA patients (median age 57 years, 88% women) were compared with 32 control individuals (median age 63 years, 62% women). Pulmonary CT-scans performed for lung assessment were available for all individuals. For the purpose of our study, complete involution of the thymus was defined as the absence of a residual thymus or a gland thickness, corresponding to the short axis on the axial slice, of less than 7 mm. We defined incomplete involution of the thymus as a residual thymic tissue more than 7 mm thick.ResultsThe frequency of incomplete thymus involution was significantly higher in SSc and RA patients (respectively 15 and 14%) than in the control group (0%; P < 0.05). Incomplete thymus involution was associated with pulmonary restrictive syndrome in SSc patients, and with biotherapy and an absence of antinuclear antibodies in RA patients.ConclusionOur findings show that two autoimmune diseases, SSc and RA, are associated with incomplete thymus involution.  相似文献   
46.
Vasculopathy, immunological abnormalities, and fibrosis are the key features in the pathogenesis of systemic sclerosis (SSc). Expression of each of the three pathologic features varies among SSc patients leading to disease heterogeneity and variable organ manifestations. Although the etiology of SSc has not yet been fully elucidated, a growing body of evidence suggests that extracellular matrix overproduction by activated fibroblasts results from a complex interplay between endothelial cells, immune cells and fibroblasts through cell–cell and cell–matrix interactions and communications. Relevant animal models are essential tools to in-depth investigate pathogenesis of SSc. Several murine and avian models are available; however, some models display inflammation followed by fibrosis, whether some others primarily mimic autonomous fibroblast activation. In addition, typical microvascular changes of SSc are only observed in few models. Therefore, none of these animal models encompasses all features of the human disease and a critical selection is mandatory for successful in vivo studies. Hence, we will provide an overview of the most important experimental models of dermal fibrosis and SSc and discuss their respective contribution to the better understanding of SSc pathogenesis.  相似文献   
47.
48.
The course of autosomal dominant polycystic kidney disease (ADPKD) varies among individuals, with some reaching ESRD before 40 years of age and others never requiring RRT. In this study, we developed a prognostic model to predict renal outcomes in patients with ADPKD on the basis of genetic and clinical data. We conducted a cross-sectional study of 1341 patients from the Genkyst cohort and evaluated the influence of clinical and genetic factors on renal survival. Multivariate survival analysis identified four variables that were significantly associated with age at ESRD onset, and a scoring system from 0 to 9 was developed as follows: being male: 1 point; hypertension before 35 years of age: 2 points; first urologic event before 35 years of age: 2 points; PKD2 mutation: 0 points; nontruncating PKD1 mutation: 2 points; and truncating PKD1 mutation: 4 points. Three risk categories were subsequently defined as low risk (0–3 points), intermediate risk (4–6 points), and high risk (7–9 points) of progression to ESRD, with corresponding median ages for ESRD onset of 70.6, 56.9, and 49 years, respectively. Whereas a score ≤3 eliminates evolution to ESRD before 60 years of age with a negative predictive value of 81.4%, a score >6 forecasts ESRD onset before 60 years of age with a positive predictive value of 90.9%. This new prognostic score accurately predicts renal outcomes in patients with ADPKD and may enable the personalization of therapeutic management of ADPKD.  相似文献   
49.
Thiophene derivatives, a class of compounds widely used in products such as pharmaceuticals, agrochemicals or dyestuffs, represent chemicals of concern. Indeed, the thiophene ring is often considered as a structural moiety that may be involved in toxic effects in humans. We primarily focus on the genotoxic/mutagenic and carcinogenic potentials of the methyl 3‐amino‐4‐methylthiophene‐2‐carboxylate (1), a precursor of the articaine local anesthetic (4) which falls within the scope of the European REACH (Registration, Evaluation, Authorisation and restriction of CHemicals) legislation. To discern some structure–toxicity relationships, we also studied two related compounds, namely the 3‐amino 4‐methylthiophene (2) and the 2‐acetyl 4‐chlorothiophene (3). Techniques employed to assess mutagenic and DNA‐damaging effects involved the Salmonella mutagenicity assay (or Ames test) and the single‐cell gel electrophoresis assay (or Comet assay). In the range of tested doses, none of these derivatives led to a positive response in the Ames tests and DNA damage was only observed in the Comet assay after high concentration exposure of 2. The study of their carcinogenic potential using the in vitro SHE (Syrian Hamster Embryo) cell transformation assay (CTA) highlighted the activity of compound 2. A combination of experimental data with in silico predictions of the reactivity of thiophene derivatives towards cytochrome P450 (CYP450), enabled us to hypothesize possible pathways leading to these toxicological profiles. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
50.
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