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81.
Carmen Barba Rita Formisano Umberto Sabatini Paola Cicinelli Gisela Elisabeth Hagberg Barbara Marconi 《Neurocase》2013,19(4):232-235
We report on a patient with left hemiparesis and peripersonal neglect after post-traumatic left frontal hemorrhage, who underwent fMRI, TMS and TCD to identify the functional abnormalities that account for his neurological symptoms, in the absence of any detectable lesion affecting right motor areas. 相似文献
82.
Helga Bergmeister Catharina Schreiber Christian Grasl Ingrid Walter Roberto Plasenzotti Martin Stoiber David Bernhard Heinrich Schima 《Acta biomaterialia》2013,9(4):6032-6040
Pore size and porosity control the rate and depth of cellular migration in electrospun vascular fabrics and thus have a strong impact on long-term graft success. In this study we investigated the effect of graft porosity on cell migration in vitro and in vivo. Polyurethane (PU) grafts were fabricated by electrospinning as fine-mesh, low-porosity grafts (void fraction (VF) 53%) and coarse-mesh, high-porosity grafts (VF 80%). The fabricated grafts were evaluated in vitro for endothelial cell attachment and proliferation. Prostheses were investigated in a rat model for either 7 days, 1, 3 or 6 months (n = 7 per time point) and analyzed after retrieval by biomechanical analysis and various histological techniques. Cell migration was calculated by computer-assisted morphometry. In vitro, fine-pore mesh favored early cell attachment. In vivo, coarse mesh grafts revealed significantly higher cell populations at all time points in all areas of the conduit wall. Biomechanical tests indicated sufficient compliance, tensile and suture retention strength before and after implantation. Increased porosity improves host cell ingrowth and survival in electrospun conduits. These conduits show successful natural host vessel reconstitution without limitation of biomechanical properties. 相似文献
83.
Kim Freriks Henri J.L.M. Timmers Romana T. Netea-Maier Catharina C.M. Beerendonk Barto J. Otten Janiëlle A.E.M. van Alfen-van der Velden Maaike A.F. Traas Hanneke Mieloo Guillaume W.H.J.F.L. van de Zande Lies H. Hoefsloot Ad R.M.M. Hermus Dominique F.C.M. Smeets 《European journal of medical genetics》2013,56(9):497-501
Turner syndrome (TS) is the result of (partial) X chromosome monosomy. In general, the diagnosis is based on karyotyping of 30 blood lymphocytes. This technique, however, does not rule out tissue mosaicism or low grade mosaicism in the blood. Because of the associated risk of gonadoblastoma, mosaicism is especially important in case this involves a Y chromosome. We investigated different approaches to improve the detection of mosaicisms in 162 adult women with TS (mean age 29.9 ± 10.3). Standard karyotyping identified 75 patients (46.3%) with a non-mosaic monosomy 45,X. Of these 75 patients, 63 underwent additional investigations including FISH on buccal cells with X- and Y-specific probes and PCR-Y on blood. FISH analysis of buccal cells revealed a mosaicism in 19 of the 63 patients (30.2%). In five patients the additional cell lines contained a (derivative) Y chromosome. With sensitive real-time PCR we confirmed the presence of this Y chromosome in blood in three of the five cases. Although Y chromosome material was established in ovarian tissue in two patients, no gonadoblastoma was found. Our results confirm the notion that TS patients with 45,X on conventional karyotyping often have tissue specific mosaicisms, some of which include a Y chromosome. Although further investigations are needed to estimate the risk of gonadoblastoma in patients with Y chromosome material in buccal cells, we conclude that FISH or real-time PCR on buccal cells should be considered in TS patients with 45,X on standard karyotyping. 相似文献
84.
85.
Zar HJ Workman L Isaacs W Munro J Black F Eley B Allen V Boehme CC Zemanay W Nicol MP 《Clinical infectious diseases》2012,55(8):1088-1095
Background.?A rapid diagnosis of pediatric pulmonary tuberculosis (PTB) using Xpert MTB/RIF (Mycobacterium tuberculosis/rifampicin) automated testing on induced sputum (IS) is possible, but the capacity for performing IS is limited. The diagnosis using a nasopharyngeal aspirate (NPA), which can be non-invasively obtained, is desirable. Methods.?Paired specimens (NPA and IS) were tested using smear, liquid culture and Xpert. The diagnostic accuracy of Xpert and smear was compared with culture for different specimens in children with suspected PTB. Results.?There were 535 children [median age 19 months, 117 (21·9%) HIV-infected] who had one IS and one NPA specimen; 396 had two paired specimens. A positive smear, Xpert test or culture occurred in 30 (5.6%), 81 (15.1%) and 87 children (16.3%), respectively. The culture yield was higher from IS (84/87, 96.6%) vs NPA (61/87, 70.1%, P?.001). Amongst children with two paired specimens, 63 culture-confirmed cases occurred [60 (95.2%) IS vs 48 (76.2%) NPA, P?=?.002]. The sensitivity of two Xpert tests was similar for IS and NPAs [(45/63) 71% vs (41/63) 65%, P?=?.444)]; the sensitivity of smear was lower for IS (21/63, 33%) and NPA (16/63, 25%). The incremental yield from a second IS was 9 cases (17.6%) by culture and 9 (25%) by Xpert testing; a second NPA increased the culture yield by 10 (26.3%) and Xpert by 11 (36.7%). Xpert specificity was 99.1% (98.1-100) for IS and 98.2% (96.8-99.6) for NPAs. Xpert testing provided faster results than culture (median 0 vs 15 days, P?.001). Conclusions.?Xpert testing on 2 NPAs is useful in children with suspected PTB, particularly in settings where IS and culture are not feasible. 相似文献
86.
Catharina Borna Knut Kollberg David Larsson Arash Mokhtari 《Scandinavian cardiovascular journal : SCJ》2013,47(6):308-314
AbstractObjectives. Chest pain is a common complaint in the emergency department (ED), and it is a challenge to identify low-risk chest pain patients eligible for early discharge. We aimed to develop a simple objective decision rule to exclude 30-day major adverse cardiac events (MACE) in ED chest pain patients.Design. We analyzed prospectively included patients presenting with chest pain. Low risk patients were identified with the clinical objective rule-out evaluation (CORE). CORE was based on high sensitivity cardiac troponin T (hs-cTnT) tests at ED presentation (0?h) and 2?h later together with a simplified risk score consisting of four objective variables: age ≥65 years and a history of arterial disease, hypertension or diabetes. For the patient to be classified as low risk in the CORE rule, hs-cTnT had to be ≤14?ng/L both at 0 and 2?h, and the sum of the risk score had to be 0. The primary outcome was MACE within 30 days.Results. Among the 751 patients in the final analysis, 90 (11.9%) had a MACE. CORE identified 248 (33%) of patients as low risk with a sensitivity of 98.9% (CI 93.1–99.9) and a negative predictive value of 99.6% (95% CI 97.4–100) for 30-day MACE. Adding the ED physician’s interpretation of the ECG to CORE did not improve diagnostic performance.Conclusion. A simple objective decision rule (CORE) identified one-third of all patients as having a very low 30-day risk of MACE. These patients may potentially be discharged without additional investigations for acute coronary syndrome. 相似文献
87.
Anna‐Karin Persson PhD Shujun Liu MS Catharina G. Faber MD PhD Ingemar S. J. Merkies MD PhD Joel A. Black PhD Stephen G. Waxman MD PhD 《Annals of neurology》2013,73(1):140-145
Small‐fiber neuropathy (SFN) is characterized by injury to small‐diameter peripheral nerve axons and intraepidermal nerve fibers (IENF). Although mechanisms underlying loss of IENF in SFN are poorly understood, available data suggest that it results from axonal degeneration and reduced regenerative capacity. Gain‐of‐function variants in sodium channel NaV1.7 that increase firing frequency and spontaneous firing of dorsal root ganglion (DRG) neurons have recently been identified in ~30% of patients with idiopathic SFN. In the present study, to determine whether these channel variants can impair axonal integrity, we developed an in vitro assay of DRG neurite length, and examined the effect of 3 SFN‐associated variant NaV1.7 channels, I228M, M932L/V991L (ML/VL), and I720K, on DRG neurites in vitro. At 3 days after culturing, DRG neurons transfected with I228M channels exhibited ~20% reduced neurite length compared to wild‐type channels; DRG neurons transfected with ML/VL and I720K variants displayed a trend toward reduced neurite length. I228M‐induced reduction in neurite length was ameliorated by the use‐dependent sodium channel blocker carbamazepine and by a blocker of reverse Na‐Ca exchange. These in vitro observations provide evidence supporting a contribution of the I228M variant NaV1.7 channel to impaired regeneration and/or degeneration of sensory axons in idiopathic SFN, and suggest that enhanced sodium channel activity and reverse Na‐Ca exchange can contribute to a decrease in length of peripheral sensory axons. Ann Neurol 2012 相似文献
88.
89.
Helena Bergström Maria Hagströmer Jan Hagberg Liselotte Schäfer Elinder 《Research in developmental disabilities》2013,34(11):3847-3857
People with ID have an increased risk for unhealthy diets, physical inactivity and weight disturbances. The aim of the current study was to investigate the effectiveness of a novel and complex intervention to improve diet and physical activity, targeting both caregivers and residents, in community residences for people with ID. A three component intervention based on Social Cognitive Theory was developed, including: (1) appointment of a health ambassador in each community residence attending network meetings, (2) a study circle for caregivers, and (3) a health course for the residents. The intervention lasted for 12–16 months and allowed for some local tailoring. A cluster randomised controlled trial, randomised at residence level, was conducted to evaluate the effects of the intervention. Thirty community residences for people with mild or moderate ID in Stockholm County, Sweden, were included. A total of 130 participants, 74 women and 56 men aged 20–66 years, entered, and 129 participants completed the study. The primary outcome was physical activity, measured by pedometry. Secondary outcomes were BMI, waist circumference, dietary quality measured by digital photography, satisfaction with life assessed with a scale, and work routines assessed with a questionnaire. Outcomes were related to intervention fidelity. A positive intervention effect was found on physical activity, with an average increase of 1608 steps/day among participants in the intervention group (P = 0.045). The effect size was 0.29 (Cohen's d). The type of residence was found to be an effect moderator. A positive intervention effect was found as well on work routines, with an average increase of 7.1 percentage points on a self-assessment scale among residences in the intervention group (P = 0.016). No significant effects were found on BMI, waist circumference, dietary quality, or satisfaction with life. In conclusion, this innovative intervention was effective in improving physical activity and work routines. It is likely that even greater effects could be achieved by improvements in implementation strategies, leading to higher fidelity. 相似文献
90.