275 resultados para Related path
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CONTEXT: Type 2 diabetes is associated with increased fracture risk but paradoxically greater bone mineral density (BMD). Trabecular bone score (TBS) is derived from the texture of the spine dual x-ray absorptiometry (DXA) image and is related to bone microarchitecture and fracture risk, providing information independent of BMD. OBJECTIVE: This study evaluated the ability of lumbar spine TBS to account for increased fracture risk in diabetes. DESIGN AND SETTING: We performed a retrospective cohort study using BMD results from a large clinical registry for the province of Manitoba, Canada. Patients: We included 29,407 women 50 years old and older with baseline DXA examinations, among whom 2356 had diagnosed diabetes. MAIN OUTCOME MEASURES: Lumbar spine TBS was derived for each spine DXA examination blinded to clinical parameters and outcomes. Health service records were assessed for incident nontraumatic major osteoporotic fractures (mean follow-up 4.7 years). RESULTS: Diabetes was associated with higher BMD at all sites but lower lumbar spine TBS in unadjusted and adjusted models (all P < .001). The adjusted odds ratio (aOR) for a measurement in the lowest vs the highest tertile was less than 1 for BMD (all P < .001) but was increased for lumbar spine TBS [aOR 2.61, 95% confidence interval (CI) 2.30-2.97]. Major osteoporotic fractures were identified in 175 women (7.4%) with and 1493 (5.5%) without diabetes (P < .001). Lumbar spine TBS was a BMD-independent predictor of fracture and predicted fractures in those with diabetes (adjusted hazard ratio 1.27, 95% CI 1.10-1.46) and without diabetes (hazard ratio 1.31, 95% CI 1.24-1.38). The effect of diabetes on fracture was reduced when lumbar spine TBS was added to a prediction model but was paradoxically increased from adding BMD measurements. CONCLUSIONS: Lumbar spine TBS predicts osteoporotic fractures in those with diabetes, and captures a larger portion of the diabetes-associated fracture risk than BMD.
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OBJECTIVES: To compare the use of guideline-recommended medical and interventional therapies in older and younger patients with acute coronary syndromes (ACSs). DESIGN: Prospective cohort study. SETTING: Fifty-five hospitals in Switzerland. PARTICIPANTS: Eleven thousand nine hundred thirty-two patients with ACS enrolled between March 1, 2001, and June 30, 2006. ACS definition included ST-segment elevation myocardial infarction (STEMI), non-ST-segment elevation myocardial infarction (NSTEMI), and unstable angina pectoris (UA). MEASUREMENTS: Use of medical and interventional therapies was determined after exclusion of patients with contraindications and after adjustment for comorbidities. Multivariate logistic regression models were used to calculate odds ratios (ORs) per year increase in age. RESULTS: Elderly patients were less likely to receive acetylsalicylic acid (OR=0.976, 95% confidence interval (CI)=0.969-0.980) or beta-blockers (OR=0.985, 95% CI=0.981-0.989). No age-dependent difference was found for heparin use. Elderly patients with STEMI were less likely to receive percutaneous coronary intervention (PCI) or thrombolysis (OR=0.955, 95% CI=0.949-0.961). Elderly patients with NSTEMI or UA less often underwent PCI (OR=0.943, 95% CI=0.937-0.949). CONCLUSION: Elderly patients across the whole spectrum of ACS were less likely to receive guideline-recommended therapies, even after adequate adjustment for comorbidities. Prognosis of elderly patients with ACS may be improved by increasing adherence to guideline-recommended medical and interventional therapies.
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Previous electrophysiological studies revealed that human faces elicit an early visual event-related potential (ERP) within the occipito-temporal cortex, the N170 component. Although face perception has been proposed to rely on automatic processing, the impact of selective attention on N170 remains controversial both in young and elderly individuals. Using early visual ERP and alpha power analysis, we assessed the influence of aging on selective attention to faces during delayed-recognition tasks for face and letter stimuli, examining 36 elderly and 20 young adults with preserved cognition. Face recognition performance worsened with age. Aging induced a latency delay of the N1 component for faces and letters, as well as of the face N170 component. Contrasting with letters, ignored faces elicited larger N1 and N170 components than attended faces in both age groups. This counterintuitive attention effect on face processing persisted when scenes replaced letters. In contrast with young, elderly subjects failed to suppress irrelevant letters when attending faces. Whereas attended stimuli induced a parietal alpha band desynchronization within 300-1000 ms post-stimulus with bilateral-to-right distribution for faces and left lateralization for letters, ignored and passively viewed stimuli elicited a central alpha synchronization larger on the right hemisphere. Aging delayed the latency of this alpha synchronization for both face and letter stimuli, and reduced its amplitude for ignored letters. These results suggest that due to their social relevance, human faces may cause paradoxical attention effects on early visual ERP components, but they still undergo classical top-down control as a function of endogenous selective attention. Aging does not affect the face bottom-up alerting mechanism but reduces the top-down suppression of distracting letters, possibly impinging upon face recognition, and more generally delays the top-down suppression of task-irrelevant information.
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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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BACKGROUND: Genes involved in arbuscular mycorrhizal (AM) symbiosis have been identified primarily by mutant screens, followed by identification of the mutated genes (forward genetics). In addition, a number of AM-related genes has been identified by their AM-related expression patterns, and their function has subsequently been elucidated by knock-down or knock-out approaches (reverse genetics). However, genes that are members of functionally redundant gene families, or genes that have a vital function and therefore result in lethal mutant phenotypes, are difficult to identify. If such genes are constitutively expressed and therefore escape differential expression analyses, they remain elusive. The goal of this study was to systematically search for AM-related genes with a bioinformatics strategy that is insensitive to these problems. The central element of our approach is based on the fact that many AM-related genes are conserved only among AM-competent species. RESULTS: Our approach involves genome-wide comparisons at the proteome level of AM-competent host species with non-mycorrhizal species. Using a clustering method we first established orthologous/paralogous relationships and subsequently identified protein clusters that contain members only of the AM-competent species. Proteins of these clusters were then analyzed in an extended set of 16 plant species and ranked based on their relatedness among AM-competent monocot and dicot species, relative to non-mycorrhizal species. In addition, we combined the information on the protein-coding sequence with gene expression data and with promoter analysis. As a result we present a list of yet uncharacterized proteins that show a strongly AM-related pattern of sequence conservation, indicating that the respective genes may have been under selection for a function in AM. Among the top candidates are three genes that encode a small family of similar receptor-like kinases that are related to the S-locus receptor kinases involved in sporophytic self-incompatibility. CONCLUSIONS: We present a new systematic strategy of gene discovery based on conservation of the protein-coding sequence that complements classical forward and reverse genetics. This strategy can be applied to diverse other biological phenomena if species with established genome sequences fall into distinguished groups that differ in a defined functional trait of interest.
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Selection of action may rely on external guidance or be motivated internally, engaging partially distinct cerebral networks. With age, there is an increased allocation of sensorimotor processing resources, accompanied by a reduced differentiation between the two networks of action selection. The present study examines the age effects on the motor-related oscillatory patterns related to the preparation of externally and internally guided movements. Thirty-two older and 30 younger adults underwent three delayed motor tasks with S1 as preparatory and S2 as imperative cue: Full, laterality instructed by S1 (external guidance); Free, laterality freely selected (internal guidance); None, laterality instructed by S2 (no preparation). Electroencephalogram (EEG) was recorded using 64 surface electrodes. Motor-Related Amplitude Asymmetries (MRAA), indexing the lateralization of oscillatory activities, were analyzed within the S1-S2 interval in the mu (9-12 Hz) and low beta (15-20 Hz) motor-related frequency bands. Reaction times to S2 were slower in older than younger subjects, and slower in the Free than in the Full condition in older subjects only. In the Full condition, there were significant mu MRAA in both age groups, and significant low beta MRAA only in older adults. The Free condition was associated with large mu MRAA in younger adults and limited low beta MRAA in older adults. In younger subjects, the lateralization of mu activity in both Full and Free conditions indicated effective external and internal motor preparation. In older subjects, external motor preparation was associated with lateralization of low beta in addition with mu activity, compatible with an increase of motor-related resources. In contrast, absence of mu and limited low beta lateralization in internal motor preparation was concomitant with reaction time slowing and suggested less efficient cerebral processes subtending free movement selection in older adults, indicating reduced capacity for internally driven action with age.
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BACKGROUND: The effects of intravenous thrombolysis on floating thrombi in cervical and intracranial arteries of acute ischemic stroke patients are unknown. Similarly, the best prevention methods of early recurrences remain controversial. This study aimed to describe the clinical and radiological outcome of thrombolyzed strokes with floating thrombi. METHODS: We retrospectively analyzed all thrombolyzed stroke patients in our institution between 2003 and 2010 with floating thrombi on acute CT-angiography before the intravenous thrombolysis. The floating thrombus was diagnosed if an elongated thrombus of at least 5 mm length, completely surrounded by contrast on supra-aortic neck or intracerebral arteries, was present on CT-angiography. Demographics, vascular risk factors, and comorbidities were recorded and stroke etiology was determined after a standardized workup. Repeat arterial imaging was performed by CTA at 24 h or before if clinical worsening was noted and then by Doppler and MRA during the first week and at four months. RESULTS: Of 409 thrombolyzed stroke patients undergoing acute CT Angiography, seven (1.7%) had a floating thrombus; of these seven, six had it in the anterior circulation. Demographics, risk factors and stroke severity of these patients were comparable to the other thrombolyzed patients. After intravenous thrombolysis, the floating thrombi resolved completely at 24 h in four of the patients, whereas one had an early recurrent stroke and one developed progressive worsening. One patient developed early occlusion of the carotid artery with floating thrombus and subsequently a TIA. The two patients with a stable floating thrombus had no clinical recurrences. In the literature, only one of four reported cases were found to have a thrombolysis-related early recurrence. CONCLUSIONS: Long-term outcome seemed similar in thrombolyzed patients with floating thrombus, despite a possible increase of very early recurrence. It remains to be established whether acute mechanical thrombectomy could be a safer and more effective treatment to prevent early recurrence. However, intravenous thrombolysis should not be withheld in eligible stroke patients.
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Decline in gait stability has been associated with increased fall risk in older adults. Reliable and clinically feasible methods of gait instability assessment are needed. This study evaluated the relative and absolute reliability and concurrent validity of the testing procedure of the clinical version of the Narrow Path Walking Test (NPWT) under single task (ST) and dual task (DT) conditions. Thirty independent community-dwelling older adults (65-87 years) were tested twice. Participants were instructed to walk within the 6-m narrow path without stepping out. Trial time, number of steps, trial velocity, number of step errors, and number of cognitive task errors were determined. Intraclass correlation coefficients (ICCs) were calculated as indices of agreement, and a graphic approach called "mountain plot" was applied to help interpret the direction and magnitude of disagreements between testing procedures. Smallest detectable change and smallest real difference (SRD) were computed to determine clinically relevant improvement at group and individual levels, respectively. Concurrent validity was assessed using Performance Oriented Mobility Assessment Tool (POMA) and the Short Physical Performance Battery (SPPB). Test-retest agreement (ICC1,2) varied from 0.77 to 0.92 in ST and from 0.78 to 0.92 in DT conditions, with no apparent systematic differences between testing procedures demonstrated by the mountain plot graphs. Smallest detectable change and smallest real change were small for motor task performance and larger for cognitive errors. Significant correlations were observed for trial velocity and trial time with POMA and SPPB. The present results indicate that the NPWT testing procedure is highly reliable and reproducible.
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Treatment of status epilepticus (SE) consists in the sequential administration of three lines of drugs. The first is represented by benzodiazepines, and enjoys quite robust scientific evidence. The second one includes (phos-) phenytoin, valproate, phenobarbital, and increasingly levetiracetam, but its rationale is relatively scarce. The third line is pharmacological coma induction with barbiturates, propofol, or midazolam, which lacks the support of prospective, controlled studies and is reserved for refractory SE. Several other drugs are used after failure of this scheme, including newer antiepileptic compounds, other medications, and non-pharmacological approaches; no comparative assessment of their respective role has been conducted. It is important to tailor this relatively simple protocol to each particular situation; the supposed advantages of coma induction should be balanced with the morbidity related to prolonged mechanical ventilation. Awide consensus exists to treat generalized-convulsive SE and SE in coma soon and aggressively, to prevent a dismal outcome. On the other side, it is unclear if complex-partial SE induces permanent neuronal damage, and absence SE has an excellent prognosis: it appears therefore advisable not to proceed automatically to coma induction in these cases. SE related to post-anoxic coma has generally a poor prognosis, but some selected cases seem to be amenable to a better outcome if treated. SE prognosis depends on etiology, the biological background including age and comorbidities, and, possibly, treatment; each of these points deserves to be specifically addressed. A simple prognostic score has been recently validated and, helping to orient early treatment strategies and improve SE management.
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Objectives: The aim of this study was to evaluate the efficacy of brief motivational intervention (BMI) in reducing alcohol use and related problems among binge drinkers randomly selected from a census of 20 year-old French speaking Swiss men and to test the hypothesis that BMI contributes to maintain low-risk drinking among non-bingers. Methods: Randomized controlled trial comparing the impact of BMI on weekly alcohol use, frequency of binge drinking and occurrence of alcohol-related problems. Setting: Army recruitment center. Participants: A random sample of 622 men were asked to participate, 178 either refused, or missed appointment, or had to follow military assessment procedures instead, resulting in 418 men randomized into BMI or control conditions, 88.7% completing the 6-month follow-up assessment. Intervention: A single face-to-face BMI session exploring alcohol use and related problems in order to stimulate behaviour change perspective in a non-judgmental, empathic manner based on the principles of motivational interviewing (MI). Main outcome measures: Weekly alcohol use, binge drinking frequency and the occurrence of 12 alcohol-related consequences. Results: Among binge drinkers, we observed a 20% change in drinking induced by BMI, with a reduction in weekly drinking of 1.5 drink in the BMI group, compared to an increase of 0.8 drink per week in the control group (incidence rate ratio 0.8, 95% confidence interval 0,66 to 0,98, p = 0.03). BMI did not influence the frequency of binge drinking and the occurrence of 12 possible alcohol-related consequences. However, BMI induced a reduction in the alcohol use of participants who, after drinking over the past 12 months, experienced alcohol-related consequences, i.e., hangover (-20%), missed a class (-53%), got behind at school (-54%), argued with friends (-38%), engaged in unplanned sex (-45%) or did not use protection when having sex (-64%). BMI did not reduce weekly drinking in those who experienced the six other problems screened. Among non-bingers, BMI did not contribute to maintain low-risk drinking. Conclusions: At army conscription, BMI reduced alcohol use in binge drinkers, particularly in those who recently experienced alcohol-related adverse consequences. No preventive effect of BMI was observed among non-bingers. BMI is an interesting preventive option in young binge drinkers, particularly in countries with mandatory army recruitment.
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BACKGROUND: This study assessed whether breast cancer (BC) patients express similar levels of needs for equivalent severity of symptoms, functioning difficulties, or degrees of satisfaction with care aspects. BC patients who did (or not) report needs in spite of similar difficulties were identified among their sociodemographic or clinical characteristics. PATIENTS AND METHODS: Three hundred and eighty-four (73% response rate) BC patients recruited in ambulatory or surgery hospital services completed the European Organisation for Research and Treatment of Cancer Quality of Life questionnaire (EORTC QLQ)-C30 quality of life [health-related quality of life (HRQOL)], the EORTC IN-PATSAT32 (in-patient) or OUT-PATSAT35 (out-patient) satisfaction with care, and the supportive care needs survey short form 34-item (SCNS-SF34) measures. RESULTS: HRQOL or satisfaction with care scale scores explained 41%, 45%, 40% and 22% of variance in, respectively, psychological, physical/daily living needs, information/health system, and care/support needs (P < 0.001). BC patients' education level, having children, hospital service attendance, and anxiety/depression levels significantly predicted differences in psychological needs relative to corresponding difficulties (adjusted R(2) = 0.11). Medical history and anxiety/depression levels significantly predicted differences in information/health system needs relative to degrees of satisfaction with doctors, nurses, or radiotherapy technicians and general satisfaction (adjusted R(2) = 0.12). Unmet needs were most prevalent in the psychological domains across hospital services. CONCLUSIONS: Assessment of needs, HRQOL, and satisfaction with care highlights the subgroups of BC patients requiring better supportive care targeting.
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The release of transmitters from glia influences synaptic functions. The modalities and physiological functions of glial release are poorly understood. Here we show that glutamate exocytosis from astrocytes of the rat hippocampal dentate molecular layer enhances synaptic strength at excitatory synapses between perforant path afferents and granule cells. The effect is mediated by ifenprodil-sensitive NMDA ionotropic glutamate receptors and involves an increase of transmitter release at the synapse. Correspondingly, we identify NMDA receptor 2B subunits on the extrasynaptic portion of excitatory nerve terminals. The receptor distribution is spatially related to glutamate-containing synaptic-like microvesicles in the apposed astrocytic processes. This glial regulatory pathway is endogenously activated by neuronal activity-dependent stimulation of purinergic P2Y1 receptors on the astrocytes. Thus, we provide the first combined functional and ultrastructural evidence for a physiological control of synaptic activity via exocytosis of glutamate from astrocytes.