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This study describes the use of oligo [(polyethylene glycol) fumarate] (OPF) hydrogel scaffolds as vehicles for sustained delivery of dibutyryl cyclic adenosine monophosphate (dbcAMP) to the transected spinal cord. dbcAMP was encapsulated in poly(lactic-co-glycolic acid) (PLGA) microspheres, which were embedded within the scaffolds architecture. Functionality of the released dbcAMP was assessed using neurite outgrowth assays in PC12 cells and by delivery to the transected spinal cord within OPF seven channel scaffolds, which had been loaded with Schwann cells or mesenchymal stem cells (MSCs). Our results showed that encapsulation of dbcAMP in microspheres lead to prolonged release and continued functionality in vitro. These microspheres were then successfully incorporated into OPF scaffolds and implanted in the transected thoracic spinal cord. Sustained delivery of dbcAMP inhibited axonal regeneration in the presence of Schwann cells but rescued MSC-induced inhibition of axonal regeneration. dbcAMP was also shown to reduce capillary formation in the presence of MSCs, which was coupled with significant functional improvements. Our findings demonstrate the feasibility of incorporating PLGA microsphere technology for spinal cord transection studies. It represents a novel sustained delivery mechanism within the transected spinal cord and provides a platform for potential delivery of other therapeutic agents.  相似文献   
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El‐Hattab AW, Bournat J, Eng PA, Wu JBS, Walker BA, Stankiewicz P, Cheung SW, Brown CW. Microduplication of Xp11.23p11.3 with effects on cognition, behavior, and craniofacial development. We report an ~1.3 Mb tandem duplication at Xp11.23p11.3 in an 11‐year‐old boy with pleasant personality, hyperactivity, learning and visual‐spatial difficulties, relative microcephaly, long face, stellate iris pattern, and periorbital fullness. This clinical presentation is milder and distinct from that of patients with partially overlapping Xp11.22p11.23 duplications which have been described in males and females with intellectual disability, language delay, autistic behaviors, and seizures. The duplicated region harbors three known X‐linked mental retardation genes: FTSJ1, ZNF81, and SYN1. Quantitative polymerase chain reaction from whole blood total RNA showed increased expression of three genes located in the duplicated region: EBP, WDR13, and ZNF81. Thus, over‐expression of genes in the interval may contribute to the observed phenotype. Many of the features seen in this patient are present in individuals with Williams‐Beuren syndrome (WBS). Interestingly, the SYN1 gene within the duplicated interval, as well as the STX1A gene, within the WBS critical region, co‐localize to presynaptic active zones, and play important roles in neurotransmitter release.  相似文献   
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The most common indication for an echocardiogram is for the assessment of left ventricular (LV) function and, in the evaluation of cardiomyopathy (CM), this becomes even more important. However, conventional echocardiographic measures of ventricular function are insensitive at detecting subtle perturbations in contractility. In patients with CM, the ability to detect abnormalities early in the course of the disease to establish a diagnosis can be critical and often may influence specific treatments administered as well as establish important prognostic information. Technologic advances in echocardiographic imaging during the last decade now allow for the measurement of LV strain and strain rate (SR) imaging. Strain and SR imaging allow for a more precise characterization of the mechanics of myocardial contraction and relaxation (deformation imaging) and emerging data are establishing the use of these techniques in a variety of different cardiomyopathic conditions. After establishing a common understanding of strain imaging as well as defining the methods by which these measures can be incorporated into an echocardiographic examination, we will review the accumulating information illustrating the great promise that this imaging modality has in the care of patients with CM. This review will focus on the role of strain and SR imaging in CM.  相似文献   
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Background: Vertical Banded Gastroplasty (VBG) is one of the most common bariatric operations. It can be performed by open or laparoscopic methods. The purpose of this study was to analyze and compare the 1-year results of 40 patients who underwent laparoscopic (20) and open (20). Methods: The initial 20 patients undergoing LaparoscopicVBG and the initial 20 patients in whom an Open VBG were performed in our Institution were comparatively evaluated. Demography, surgical details, complications, and 1-year weight loss were analyzed. Results: Both groups were highly comparable in terms of age, sex and body mass index. Laparoscopic VBG was a more prolonged procedure (median 4 hr) than the open VBG (median 3 hr). On the other hand, hospital stay was significantly shorter in the laparoscopic procedure (median 10 days for the open and 6 days for the laparoscopic). One year weight loss and complications were similar in both groups. Conclusions: Laparoscopic VBG is a safe procedure for the treatment of morbid obesity. This initial series shows comparable results.  相似文献   
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