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931.

Introduction

The DWI/FLAIR mismatch is a potential radiological marker for the timing of stroke onset. The aim of the study was to assess if the DWI/FLAIR mismatch can help to identify patients with both lacunar and nonlacunar acute ischemic stroke within 4.5 h of onset.

Methods

A retrospective study was performed in which the authors analysed data from 86 ischemic lacunar and nonlacunar stroke patients with a known time of symptom onset, imaged within the first 24 h from stroke onset (36 patients <4.5 h, 14 patients 4.5–6 h, 15 patients 6–12 h, and 21 patients 12–24 h). Patients underwent the admission CT and MR scan. The presence of lesions was assessed in correlation with the duration of the stroke.

Results

The time from stroke onset to neuroimaging was significantly shorter in patients with an ischemic lesion visible only in the DWI (mean 2.78 h, n?=?24) as compared to patients with signs of ischemia also in other modalities (mean 8.6 h, n?=?62) (p?=?0.0001, Kruskal–Wallis ANOVA). The DWI/FLAIR mismatch was characterised by a global sensitivity of 58 %, specificity 94 %, PPV 87.5 %, and NPV 76 % in identifying patients in the 4.5 h thrombolysis time window. For lacunar strokes (n?=?20), these parameters were as follows: sensitivity 50 %, specificity 92.8 %, PPV 75 %, and NPV 81.2 %.

Conclusions

The presence of acute ischemic lesions only in DWI can help to identify both lacunar and nonlacunar stroke patients who are in the 4.5 h time window for intravenous thrombolysis with high specificity.  相似文献   
932.
933.
934.
Recombination activating gene 2 (RAG2) deficiency results in severe combined immunodeficiency (SCID) with complete lack of T and B lymphocytes. Initial gammaretroviral gene therapy trials for other types of SCID proved effective, but also revealed the necessity of safe vector design. We report the development of lentiviral vectors with the spleen focus forming virus (SF) promoter driving codon-optimized human RAG2 (RAG2co), which improved phenotype amelioration compared to native RAG2 in Rag2−/− mice. With the RAG2co therapeutic transgene, T-cell receptor (TCR) and immunoglobulin repertoire, T-cell mitogen responses, plasma immunoglobulin levels and T-cell dependent and independent specific antibody responses were restored. However, the thymus double positive T-cell population remained subnormal, possibly due to the SF virus derived element being sensitive to methylation/silencing in the thymus, which was prevented by replacing the SF promoter by the previously reported silencing resistant element (ubiquitous chromatin opening element (UCOE)), and also improved B-cell reconstitution to eventually near normal levels. Weak cellular promoters were effective in T-cell reconstitution, but deficient in B-cell reconstitution. We conclude that immune functions are corrected in Rag2−/− mice by genetic modification of stem cells using the UCOE driven codon-optimized RAG2, providing a valid optional vector for clinical implementation.  相似文献   
935.
The risk of developing skin cancers is dependent on a combination of environmental factors and personal genetic predispositions. Basal cell carcinoma (BCC) has been associated with single nucleotide polymorphisms in several pigmentation genes; however, there is still controversy concerning the mechanism by which these variants may increase the risk of BCC. The pathway may lead to pigmentation alone, but evidence for their independent influence is growing. Using a single base extension protocol, candidate polymorphisms within 11 known pigment-related genes were studied for their association with BCC in a population sample consisting of 164 patients and 707 controls. The significance of variation within the MC1R gene was confirmed and, in addition, position rs12203592 within the IRF4 gene was shown to be associated with BCC. These associations remained significant after adjustment for skin color. Gene-gene interactions were found to influence susceptibility to BCC. Among interacting genes are the two above-mentioned loci with main effect on BCC risk and additionally KITLG, TYRP1, ASIP and TYR. The obtained results indicate that polymorphism at MC1R and IRF4 constitute pigmentation-independent risk factor in the development of BCC. Moreover, susceptibility to BCC may be influenced by epistatic effects between pigmentation genes.  相似文献   
936.
Pheomelanin is supposed to be the first type of melanin found in vertebrates, in contrast to the main type - eumelanin. Our study aimed at detecting pheomelanin in the skin of Hymenochirus boettgerii. We employed electron paramagnetic resonance (EPR) spectroscopy, and transmission electron microscopy (TEM), supplemented with standard histology and immunochemistry. We identified pheomelanin in the dorsal skin of adult frogs (not only in the dermis, but also in the epidermis) and in the dorsal tadpole. Our work identifies Hymenochirus boettgerii as a model in the basic study on the mechanism, evolution and role of melanogenesis in animals, including human.  相似文献   
937.
938.
Background and purposeThe aetiopathogenesis of fatigue in multiple sclerosis (MS) is not clear. It could be associated with structural changes of the central nervous system, but also with mood and sleep disorders. The purpose of the study was to evaluate frequency of fatigue and its association with sleep and mood disorders in MS patients.Material and methodsThe examined group consisted of 122 MS patients (mean age 37.7 ± 10.8 years). The following questionnaires were used: Fatigue Severity Scale (FSS), Epworth Sleepiness Scale (ESS), Athens Insomnia Scale (AIS), Montgomery-Asberg Depression Rating Scale (MADRS), and Hospital Anxiety and Depression Scale (HADS).ResultsFatigue was present in 75 MS patients (61.5%). Excessive daytime sleepiness was observed in 25 (20.5%), insomnia in 73 patients (59.8%). According to MADRS, depressive symptoms were present in 33 (27%), according to HADS in 15 people (12.3%). Anxiety was present in 32 patients (26.2%). We observed an association between fatigue (FSS) and sleep disorders (ESS, AIS) and also between fatigue and either depression (MADRS, HADS-D) or anxiety (HADS-A). The FSS score was not associated with age, sex, disease course and duration, Expanded Disability Status Stage (EDSS), treatment or level of education in MS patients. In inactive professionally people we noted significantly higher FSS scores (44.8 ± 13.8) in comparison with active individuals (37.2 ± 14.9; p = 0.0053).ConclusionsFatigue is a very common symptom in MS, sometimes associated with sleep disorders, depressive symptoms or anxiety. The treatable causes of fatigue in MS such as sleep and mood disturbances should be identified and treated.  相似文献   
939.
Background: An insulin pump is an advanced technology offering new options of bolus – normal (N), dual wave (D-W) or square wave (S-W) bolus to deliver mealtime insulin.
Objectives: To assess the impact of D-W/S-W boluses on metabolic control (glycated haemoglobin A1c, HbA1c) and to estimate the paediatric patients compliance with implementation of this system in daily practice.
Methods: The cross-sectional study included 499 records of patients aged 0–18 yr. Data from the insulin pump memory provided information on the number of D-W/S-W boluses during a 2-wk period, the insulin requirement (U/kg/d) and the percentage of basal insulin. The HbA1c value (%) and the patient's weight were determined during medical examinations. Mealtime dose of insulin in D-W/S-W bolus was calculated based on the amount of carbohydrate and fat/protein products.
Results: The number of applied D-W/S-W boluses was 16.6 ± 0.77/14 d (ranged 0–95), while 18.8% of patients did not program D-W/S-W boluses. The lowest HbA1c value was found in the group using two and/or more D-W/S-W boluses per day (p = 0.001) compared with the group administrating less than one D-W/S-W bolus/d. Patients with HbA1c level <7.5% had a statistically higher relevant number of D-W/S-W boluses, 19.55 (95% CI: 17.44–21.65) vs. 12.42 (95% CI: 10.22–14.61) (p < 0.001), while there was no correlation between the number of boluses and HbA1c in patients in the remission phase (<0.5 IU/kg/d) (r = 0.012, p = 0.930).
Conclusions: Patients using at least one D-W/S-W bolus per day achieved a recommended level of HbA1c. Paediatric patients with type 1 diabetes mellitus were found to be able to apply D-W/S-W boluses in daily self-treatment process based on food counting.  相似文献   
940.
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