113 resultados para vierailu - 1878
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RATIONALE AND OBJECTIVES: To systematically review and meta-analyze published data about the diagnostic accuracy of fluorine-18-fluorodeoxyglucose ((18)F-FDG) positron emission tomography (PET) and PET/computed tomography (CT) in the differential diagnosis between malignant and benign pleural lesions. METHODS AND MATERIALS: A comprehensive literature search of studies published through June 2013 regarding the diagnostic performance of (18)F-FDG-PET and PET/CT in the differential diagnosis of pleural lesions was carried out. All retrieved studies were reviewed and qualitatively analyzed. Pooled sensitivity, specificity, positive and negative likelihood ratio (LR+ and LR-) and diagnostic odds ratio (DOR) of (18)F-FDG-PET or PET/CT in the differential diagnosis of pleural lesions on a per-patient-based analysis were calculated. The area under the summary receiver operating characteristic curve (AUC) was calculated to measure the accuracy of these methods. Subanalyses considering device used (PET or PET/CT) were performed. RESULTS: Sixteen studies including 745 patients were included in the systematic review. The meta-analysis of 11 selected studies provided the following results: sensitivity 95% (95% confidence interval [95%CI]: 92-97%), specificity 82% (95%CI: 76-88%), LR+ 5.3 (95%CI: 2.4-11.8), LR- 0.09 (95%CI: 0.05-0.14), DOR 74 (95%CI: 34-161). The AUC was 0.95. No significant improvement of the diagnostic accuracy considering PET/CT studies only was found. CONCLUSIONS: (18)F-FDG-PET and PET/CT demonstrated to be accurate diagnostic imaging methods in the differential diagnosis between malignant and benign pleural lesions; nevertheless, possible sources of false-negative and false-positive results should be kept in mind.
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We have recently demonstrated that human pediatric mesenchymal stem cells can be reprogrammed toward a Ewing sarcoma family tumor (ESFT) cancer stem cell (CSC) phenotype by mechanisms that implicate microRNAs (miRNAs). Here, we show that the miRNA profile of ESFT CSCs is shared by embryonic stem cells and CSCs from divergent tumor types. We also provide evidence that the miRNA profile of ESFT CSCs is the result of reversible disruption of TARBP2-dependent miRNA maturation. Restoration of TARBP2 activity and systemic delivery of synthetic forms of either of two of its targets, miRNA-143 or miRNA-145, inhibited ESFT CSC clonogenicity and tumor growth in vivo. Our observations suggest that CSC self-renewal and tumor maintenance may depend on deregulation of TARBP2-dependent miRNA expression.
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This study provides a retrospective review from the forensic files of the University Centre of Legal Medicine in Western Switzerland in Geneva, from January 1956 to December 2005. The studied homicide-suicide cases cover a period of half a century (50 years). As a rule, all police-ordered forensic examinations of violent death cases in the Canton of Geneva are conducted by the University Centre of Legal Medicine. All of the data necessary for an exhaustive retrospective study are thus readily available. During the period covered in this work, 228 homicides were perpetrated in Geneva. In 23 cases, the homicide was followed by the suicide of the aggressor. The 34 victims of these homicides (18 women, 1 man and 15 children) had either an intimate or filial relationship with the perpetrator. Most of the suicidal perpetrators were men that killed their spouses or intimate partners, with children as additional victims in some cases. Shooting was the most common means to kill, followed by stabbing. The majority of the victims and perpetrators were Swiss nationals. This retrospective study shows that in the last 50 years, homicide-suicide cases in the Canton of Geneva have been a rare and an episodic phenomena with a very variable frequency from 1 year to another.
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In recent years, previously unsuspected roles of astrocytes have been revealed, largely owing to the development of new tools enabling their selective study in situ. These exciting findings add to the large body of evidence demonstrating that astrocytes play a central role in brain homeostasis, in particular via the numerous cooperative metabolic processes they establish with neurons, such as the supply of energy metabolites and neurotransmitter recycling functions. Furthermore, impairments in astrocytic function are increasingly being recognized as an important contributor to neuronal dysfunction and, in particular, neurodegenerative processes. In this review, we discuss recent evidence supporting important roles for astrocytes in neuropathological conditions such as neuroinflammation, amyotrophic lateral sclerosis and Alzheimer's disease. We also explore the potential for neuroprotective therapeutics based on the modulation of astrocytic functions.
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Bisphosphonates are known for their strong inhibitory effect on bone resorption. Their influence on bone formation however is less clear. In this study we investigated the spatio-temporal effect of locally delivered Zoledronate on peri-implant bone formation and resorption in an ovariectomized rat femoral model. A cross-linked hyaluronic acid hydrogel was loaded with the drug and applied bilaterally in predrilled holes before inserting polymer screws. Static and dynamic bone parameters were analyzed based on in vivo microCT scans performed first weekly and then biweekly. The results showed that the locally released Zoledronate boosted bone formation rate up to 100% during the first 17 days after implantation and reduced the bone resorption rate up to 1000% later on. This shift in bone remodeling resulted in an increase in bone volume fraction (BV/TV) by 300% close to the screw and 100% further away. The double effect on bone formation and resorption indicates a great potential of Zoledronate-loaded hydrogel for enhancement of peri-implant bone volume which is directly linked to improved implant fixation.
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Congenital hypogonadotrophic hypogonadism (CHH) is a rare form of infertility caused by deficient secretion or action of gonadotrophin-releasing hormone. There is no consensus regarding the optimal approach to fertility treatment in CHH men. In most cases, appropriate hormonal treatment with human chorionic gonadotrophin with or without follicle stimulating hormone will induce testicular development, spermatogenesis and fertility. Recent studies have examined sequential treatment with FSH pre-treatment to optimize fertility outcomes in severely affected CHH patients. This paper reviews historical and recent literature to summarize the current evidence on therapeutic approaches for CHH men seeking fertility.
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Present interventions to repair severed peripheral nerves provide slow and poor early axonal regeneration, which may cause unsatisfactory functional reinnervation. To improve early axonal regeneration in a 10 mm rat sciatic nerve gap model, we developed collagen nerve conduits loaded with the synergistically acting glial cell line-derived neurotrophic factor (GDNF) and nerve growth factor (NGF). For controlling the concomitant GDNF and NGF release, the collagen tubes were cross-linked by a dehydro-thermal treatment (110 degrees C; 20 mbar; 5 days) prior to impregnating the tubes with GDNF and NGF and by coating drug-loaded tubes with layers of poly(lactide-co-glycolide). The conduits made of cross-linked collagen released low initial amounts of GDNF and NGF (2% of both during first 3 days) and enhanced significantly the early (2 weeks) nerve regeneration in terms of axonal outgrowth and Schwann cell migration in a 10 mm rat sciatic nerve gap model, as compared to the conduits made of non-cross-linked collagen releasing higher initial amounts of GDNF and NGF (12-16% within 3 days), or those releasing GDNF alone. The enhancement of early axonal regeneration using controlled co-delivery of multiple synergistic neurotrophic factors is an important requisite for eventually establishing functional connections with the target organ.
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OBJECTIVE: The aim of this study was to determine whether V˙O(2) kinetics and specifically, the time constant of transitions from rest to heavy (τ(p)H) and severe (τ(p)S) exercise intensities, are related to middle distance swimming performance. DESIGN: Fourteen highly trained male swimmers (mean ± SD: 20.5 ± 3.0 yr; 75.4 ± 12.4 kg; 1.80 ± 0.07 m) performed an discontinuous incremental test, as well as square wave transitions for heavy and severe swimming intensities, to determine V˙O(2) kinetics parameters using two exponential functions. METHODS: All the tests involved front-crawl swimming with breath-by-breath analysis using the Aquatrainer swimming snorkel. Endurance performance was recorded as the time taken to complete a 400 m freestyle swim within an official competition (T400), one month from the date of the other tests. RESULTS: T400 (Mean ± SD) (251.4 ± 12.4 s) was significantly correlated with τ(p)H (15.8 ± 4.8s; r=0.62; p=0.02) and τ(p)S (15.8 ± 4.7s; r=0.61; p=0.02). The best single predictor of 400 m freestyle time, out of the variables that were assessed, was the velocity at V˙O(2max)vV˙O(2max), which accounted for 80% of the variation in performance between swimmers. However, τ(p)H and V˙O(2max) were also found to influence the prediction of T400 when they were included in a regression model that involved respiratory parameters only. CONCLUSIONS: Faster kinetics during the primary phase of the V˙O(2) response is associated with better performance during middle-distance swimming. However, vV˙O(2max) appears to be a better predictor of T400.
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The genetic characterization of unbalanced mixed stains remains an important area where improvement is imperative. In fact, using the standard tools of forensic DNA profiling (i.e., STR markers), the profile of the minor contributor in mixed DNA stains cannot be successfully detected if its quantitative share of DNA is less than 10% of the mixed trace. This is due to the fact that the major contributor's profile "masks" that of the minor contributor. Besides known remedies to this problem, such as Y-STR analysis, a new compound genetic marker that consists of a Deletion/Insertion Polymorphism (DIP) linked to a Short Tandem Repeat (STR) polymorphism, has recently been developed and proposed [1]. These novel markers are called DIP-STR markers. This paper compares, from a statistical and forensic perspective, the potential usefulness of these novel DIP-STR markers (i) with traditional STR markers in cases of moderately unbalanced mixtures, and (ii) with Y-STR markers in cases of female-male mixtures. This is done through a comparison of the distribution of 100,000 likelihood ratio values obtained using each method on simulated mixtures. This procedure is performed assuming, in turn, the prosecution's and the defence's point of view.
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Over the last two decades, thanks to the discovery of several pharmaceutical agents, multiple sclerosis (MS) has been transformed into a treatable disorder although the degree of therapeutic response may vary considerably. As more medications find their entry into the MS market, a clinician faces a mounting challenge of comparing risk and benefit profiles of various agents in an attempt to find the best treatment approach for each individual patient. In this review, we aim to summarize the available data on safety profiles of available MS therapies while focusing mostly on serious medication specific potential adverse events without discussing the teratogenic potential of each agent (unless there is a black box warning) or hypersensitivity reactions. Our goal is to provide a clinician with guidance on assuring the appropriate safety monitoring for patients treated with one of the agents discussed. We also comment on the future of risk management in MS and discuss possible enhancements to the current model of drug approval process and general strategies to improve the patient safety.
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Genomic rearrangements at chromosome 13q31.3q32.1 have been associated with digital anomalies, dysmorphic features, and variable degree of mental disability. Microdeletions leading to haploinsufficiency of miR17∼92, a cluster of micro RNA genes closely linked to GPC5 in both mouse and human genomes, has recently been associated with digital anomalies in the Feingold like syndrome. Here, we report on a boy with familial dominant post-axial polydactyly (PAP) type A, overgrowth, significant facial dysmorphisms and autistic traits who carries the smallest germline microduplication known so far in that region. The microduplication encompasses the whole miR17∼92 cluster and the first 5 exons of GPC5. This report supports the newly recognized role of miR17∼92 gene dosage in digital developmental anomalies, and suggests a possible role of GPC5 in growth regulation and in cognitive development.
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Diabetes mellitus is a complex disease resulting in altered glucose homeostasis. In both type 1 and type 2 diabetes mellitus, pancreatic β cells cannot secrete appropriate amounts of insulin to regulate blood glucose level. Moreover, in type 2 diabetes mellitus, altered insulin secretion is combined with a resistance of insulin-target tissues, mainly liver, adipose tissue, and skeletal muscle. Both environmental and genetic factors are known to contribute to the development of the disease. Growing evidence indicates that microRNAs (miRNAs), a class of small noncoding RNA molecules, are involved in the pathogenesis of diabetes. miRNAs function as translational repressors and are emerging as important regulators of key biological processes. Here, we review recent studies reporting changes in miRNA expression in tissues isolated from different diabetic animal models. We also describe the role of several miRNAs in pancreatic β cells and insulin-target tissues. Finally, we discuss the possible use of miRNAs as blood biomarkers to prevent diabetes development and as tools for gene-based therapy to treat both type 1 and type 2 diabetes mellitus.
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The right to be treated humanely when detained is universally recognized. Deficiencies in detention conditions and violence, however, subvert this right. When this occurs, proper medico-legal investigations are critical irrespective of the nature of death. Unfortunately, the very context of custody raises serious concerns over the effectiveness and fairness of medico-legal examinations. The aim of this manuscript is to identify and discuss the practical and ethical difficulties encountered in the medico-legal investigation following deaths in custody. Data for this manuscript come from a larger project on Death in Custody that examined the causes of deaths in custody and the conditions under which these deaths should be investigated and prevented. A total of 33 stakeholders from forensic medicine, law, prison administration or national human rights administration were interviewed. Data obtained were analyzed qualitatively. Forensic experts are an essential part of the criminal justice process as they offer evidence for subsequent indictment and eventual punishment of perpetrators. Their independence when investigating a death in custody was deemed critical and lack thereof, problematic. When experts were not independent, concerns arose in relation to conflicts of interest, biased perspectives, and low-quality forensic reports. The solutions to ensure independent forensic investigations of deaths in custody must be structural and simple: setting binding standards of practice rather than detailed procedures and relying on preexisting national practices as opposed to encouraging new practices that are unattainable for countries with limited resources.