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The Greater Short-horned Lizard (Phrynosoma hernandesi) is a small reptile endemic to western North America that is classified as endangered in Canada. Here, we describe the development of 8 microsatellite markers for P. hernandesi. Observed allelic diversity varied from 2 to 11 while observed heterozygosity and expected heterozygosity ranged from 0.370–0.852 to 0.486–0.856, respectively. These markers will facilitate studies that address conservation of the species, such as levels of genetic diversity and population structure.  相似文献   
67.
With advances in the understanding of the pathophysiology of dystonia, novel therapeutics are being developed. Such therapies will require clinical investigation ranging from exploratory studies to examine safety, tolerability, dosage selection, and preliminary efficacy to confirmatory studies to evaluate efficacy definitively. As dystonia is a rare and complex disorder with clinical and etiological heterogeneity, clinical trials will require careful consideration of the trial design, including enrollment criteria, concomitant medication use, and outcome measures. Given the complexities of designing and implementing efficient clinical trials, it is important for clinicians and statisticians to collaborate closely throughout the clinical development process and that each has a basic understanding of both the clinical and statistical issues that must be addressed. To facilitate designing appropriate clinical trials in this field, we review important general clinical trial and regulatory principles, and discuss the critical components of trials with an emphasis on considerations specific to dystonia. Additionally, we discuss designs used in early exploratory, late exploratory, and confirmatory phases, including adaptive designs.  相似文献   
68.
We have designed a laboratory extracorporeal normothermic blood perfusion system for whole organs (e.g., kidney) that achieves pulsatile flow, low levels of hemolysis, and a blood priming volume of 60 mL or less. Using this uniquely designed extracorporeal circuit, we have achieved perfusion of two isolated ex vivo constructs. In the first experiment, we successfully perfused a rabbit epigastric flap based on the femoral vessels. In the second experiment, we were able to perfuse the isolated rabbit kidney for 48 h (range for all kidneys was 12–48 h) with excellent urine output, normal arterial blood gasses at 24 h, and normal ex vivo kidney histology at the conclusion of the experiments. These parameters have not been achieved before with any known or previously published laboratory extracorporeal circuits. The study has implications for prolonged organ perfusion prior to transplantation and for tissue engineering of vascularized tissues, such as by the perfusion of decellularized organs.  相似文献   
69.

Purpose

To study the protection offered by empty liposomes (LPs) alone against acrolein-induced changes in urothelial cell viability and explored uptake of LPs by primary (rat) urothelial cells.

Methods

Acrolein was used as a means to induce cellular damage and reduce urothelial cellular viability. The effect of acrolein or liposomal treatment on cellular proliferation was studied using 5-bromo-2′-deoxy-uridine assay. Cytokine release was measured after urothelial cells were exposed to acrolein. Temperature-dependent uptake study was carried out for fluorescent-labeled LPs using confocal microscopy.

Results

Liposome pretreatment protected against acrolein-induced decrease in urothelial cell proliferation. LPs also significantly affected the acrolein-induced cytokine (interferon-gamma) release offering protection to the urothelial cells against acrolein damage. We also observed a temperature-dependent urothelial uptake of fluorescent-labeled LPs occurred at 37 °C (but not at 4 °C).

Conclusions

Empty LPs alone provide a therapeutic efficacy against acrolein-induced changes in urothelial cell viability and may be a promising local therapy for bladder diseases. Hence, our preliminary evidence provides support for liposome-therapy for urothelial protection and possible repair.  相似文献   
70.
Rotator cuff tears can cause irreversible changes (e.g., fibrosis) to the structure and function of the injured muscle(s). Fibrosis leads to increased muscle stiffness resulting in increased tension at the rotator cuff repair site. This tension influences repairability and healing potential in the clinical setting. However, the micro‐ and meso‐scale structural and molecular sources of these whole‐muscle mechanical changes are poorly understood. Here, single muscle fiber and fiber bundle passive mechanical testing was performed on rat supraspinatus and infraspinatus muscles with experimentally induced massive rotator cuff tears (Tenotomy) as well as massive tears with chemical denervation (Tenotomy + BTX) at 8 and 16 weeks post‐injury. Titin molecular weight, collagen content, and myosin heavy chain profiles were measured and correlated with mechanical variables. Single fiber stiffness was not different between controls and experimental groups. However, fiber bundle stiffness was significantly increased at 8 weeks in the Tenotomy + BTX group compared to Tenotomy or control groups. Many of the changes were resolved by 16 weeks. Only fiber bundle passive mechanics was weakly correlated with collagen content. These data suggest that tendon injury with concomitant neuromuscular compromise results in extra‐cellular matrix production and increases in stiffness of the muscle, potentially complicating subsequent attempts for surgical repair. © 2014 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 32:1111–1116, 2014.  相似文献   
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