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991.
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993.
The difficulty of diagnosing active tuberculosis (TB) and lack of rapid drug susceptibility testing (DST) at the point of care remain critical obstacles to TB control. This report describes a high-intensity mycobacterium-specific-fluorophage (φ(2)GFP10) that for the first time allows direct visualization of Mycobacterium tuberculosis in clinical sputum samples. Engineered features distinguishing φ(2)GFP10 from previous reporter phages include an improved vector backbone with increased cloning capacity and superior expression of fluorescent reporter genes through use of an efficient phage promoter. φ(2)GFP10 produces a 100-fold increase in fluorescence per cell compared to existing reporter phages. DST for isoniazid and oxofloxacin, carried out in cultured samples, was complete within 36 h. Use of φ(2)GFP10 detected M. tuberculosis in clinical sputum samples collected from TB patients. DST for rifampin and kanamycin from sputum samples yielded results after 12 h of incubation with φ(2)GFP10. Fluorophage φ(2)GFP10 has potential for clinical development as a rapid, sensitive, and inexpensive point-of-care diagnostic tool for M. tuberculosis infection and for rapid DST.  相似文献   
994.
995.
Pediatric glioblastomas (GBM) including diffuse intrinsic pontine gliomas (DIPG) are devastating brain tumors with no effective therapy. Here, we investigated clinical and biological impacts of histone H3.3 mutations. Forty-two DIPGs were tested for H3.3 mutations. Wild-type versus mutated (K27M-H3.3) subgroups were compared for HIST1H3B, IDH, ATRX and TP53 mutations, copy number alterations and clinical outcome. K27M-H3.3 occurred in 71 %, TP53 mutations in 77 % and ATRX mutations in 9 % of DIPGs. ATRX mutations were more frequent in older children (p < 0.0001). No G34V/R-H3.3, IDH1/2 or H3.1 mutations were identified. K27M-H3.3 DIPGs showed specific copy number changes, including all gains/amplifications of PDGFRA and MYC/PVT1 loci. Notably, all long-term survivors were H3.3 wild type and this group of patients had better overall survival. K27M-H3.3 mutation defines clinically and biologically distinct subgroups and is prevalent in DIPG, which will impact future therapeutic trial design. K27M- and G34V-H3.3 have location-based incidence (brainstem/cortex) and potentially play distinct roles in pediatric GBM pathogenesis. K27M-H3.3 is universally associated with short survival in DIPG, while patients wild-type for H3.3 show improved survival. Based on prognostic and therapeutic implications, our findings argue for H3.3-mutation testing at diagnosis, which should be rapidly integrated into the clinical decision-making algorithm, particularly in atypical DIPG.  相似文献   
996.
Different tremor entities such as Essential Tremor (ET) or tremor in Parkinson's disease (PD) can be ameliorated by the implantation of electrodes in the ventral thalamus for Deep Brain Stimulation (DBS). The exact neural mechanisms underlying this treatment, as well as the specific pathophysiology of the tremor in both diseases to date remain elusive. Since tremor-related local field potentials (LFP) have been shown to cluster with a somatotopic representation in the subthalamic nucleus, we here investigated the neurophysiological correlates of tremor in the ventral thalamus in ET and PD using power and coherence analysis. Local field potentials (LFPs) at different recording depths and surface electromyographic signals (EMGs) from the extensor and flexor muscles of the contralateral forearm were recorded simultaneously in twelve ET and five PD patients. Data analysis revealed individual electrophysiological patterns of LFP-EMG coherence at single and double tremor frequency for each patient. Patterns observed varied in their spatial distribution within the Ventral lateral posterior nucleus of the thalamus (VLp), revealing a specific topography of 'tremor clusters' for PD and ET. The data strongly suggest that within VLp individual tremor-related electrophysiological signatures exist in ET and PD tremor.  相似文献   
997.
This research explores the phenomenon of social exclusion into a complementarist approach using interviews with six people as a starting point. Thanks to a qualitative method based on the grounded theory, we carried out a comparative analysis of our material. The analysis helped to show the traumatogenic dimension of social exclusion. We used the concept of liminality from the cultural anthropologist Victor Turner, in order to describe the destabilizing aspect of this experience, but also its potential to provoque profound change. The traumatogenic dimension appears in each story, but sometimes it provoques a real “initiatory transformation”. In other cases, it may lead to defensive psychic arrangements which are constructed on the basis of a splitting between the “sacred” and the “profane” and even really become traumatic.  相似文献   
998.
BACKGROUND AND HYPOTHESIS: Thrombolytic therapy with tissue plasminogen activator is effective for acute ischaemic stroke within 4·5?h of onset. Patients who wake up with stroke are generally ineligible for stroke thrombolysis. We hypothesized that ischaemic stroke patients with significant penumbral mismatch on either magnetic resonance imaging or computer tomography at three- (or 4·5 depending on local guidelines) to nine-hours from stroke onset, or patients with wake-up stroke within nine-hours from midpoint of sleep duration, would have improved clinical outcomes when given tissue plasminogen activator compared to placebo. STUDY DESIGN: EXtending the time for Thrombolysis in Emergency Neurological Deficits is an investigator-driven, Phase III, randomized, multicentre, double-blind, placebo-controlled study. Ischaemic stroke patients presenting after the three- or 4·5-h treatment window for tissue plasminogen activator and within nine-hours of stroke onset or with wake-up stroke within nine-hours from the midpoint of sleep duration, who fulfil clinical (National Institutes of Health Stroke Score ≥4-26 and prestroke modified Rankin Scale <2) will undergo magnetic resonance imaging or computer tomography. Patients who also meet imaging criteria (infarct core volume <70?ml, perfusion lesion?:?infarct core mismatch ratio >1·2, and absolute mismatch >10?ml) will be randomized to either tissue plasminogen activator or placebo. STUDY OUTCOME: The primary outcome measure will be modified Rankin Scale 0-1 at day 90. Clinical secondary outcomes include categorical shift in modified Rankin Scale at 90 days, reduction in the National Institutes of Health Stroke Score by 8 or more points or reaching 0-1 at day 90, recurrent stroke, or death. Imaging secondary outcomes will include symptomatic intracranial haemorrhage, reperfusion and or recanalization at 24?h and infarct growth at day 90.  相似文献   
999.
Time to detection of Mycobacterium tuberculosis in broth culture was examined for utility as a treatment efficacy end point. Of 146 patients in a phase IIB trial, a decreased mean time to detection was found in 5 with treatment failure. Time to detection in an analysis-of-covariance model was associated with lung cavities, less intensive treatment, and differences in the bactericidal effects of treatment regimens.  相似文献   
1000.
FVIII is an important cofactor in the tenase coagulation factor complex, lack of FVIII causes severe bleeding, whereas high FVIII levels seem to be associated with venous and arterial thromboembolism. Resting platelets do not bind FVIII, but activated platelets bind unactivated FVIII if vWF is not present. We investigated a possible influence of platelet bound FVIII on platelet function itself as it is unclear if there is a direct effect of FVIII on platelet function. The influence of FVIII on platelet function was investigated by flow cytometric analysis of P-selectin expression (CD62P) and PAC-1 binding before and after submaximal stimulation with TRAP-6 (5 microM final concentration), by confocal microscopy and by platelet aggregometry. For flow cytometry and confocal microscopy, washed platelets were incubated with human recombinant FVIII for 5 min at 37 degrees C. Analysis of platelet surface area was measured by computerized image analysis. Treatment with FVIII only caused no changes in P-selectin expression or PAC-1 binding, respectively. Stimulation of platelets with TRAP-6 increased the expression of P-selectin (445%) and PAC-1 binding (934%) as expected. These effects were further increased when platelets were stimulated with TRAP-6 and FVIII (P-selectin 499%, difference not significant; PAC-1 1626%, P < 0.05. Values were expressed in%, related to unstimulated, buffer treated platelets). Platelet spreading on fibrinogen was significantly increased when platelets were treated with FVIII and TRAP-6 compared to TRAP-6 alone (368 vs. 307 average pixel/platelet, P<0.05). In addition platelet aggregation was enhanced when platelets were stimulated with FVIII and TRAP-6 compared to TRAP-6 alone. FVIII can act as a positive regulator of platelet function in TRAP-co-stimulated platelets. We hypothesize that FVIII induced increase in platelet activation might contribute to venous and even arterial thrombus formation in patients with high FVIII levels.  相似文献   
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