Publications by authors named "Nathan Wilkes"

Background: Compression pauses may be particularly harmful following the electrical recovery but prior to the mechanical recovery from cardiopulmonary arrest.

Methods And Results: A convenience sample of patients with out-of-hospital cardiac arrest (OOHCA) were identified. Data were exported from defibrillators to define compression pauses, electrocardiogram rhythm, PetCO2, and the presence of palpable pulses.

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Object: Each region of the brain is distinguished by specific and distinct markers and functions. The authors hypothesized that each region possesses unique trophic properties that dictate and maintain its development. To test this hypothesis, they isolated central nervous system (CNS) stem cells from fetal rodents, and these rat CNS-derived stem cells (RSCs) were placed in coculture with primary cultures of the developing neonatal hippocampus and hypothalamus to determine whether region-specific primary cells would direct the differentiation of stem cells in a region-specific manner.

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Fetal brain stem cells (RSCs) have been induced to express pituitary phenotypes in vitro in co-cultures with GH(3) cells and by exposure to GH(3)-conditioned media. In the current studies, we graft RSCs into the pituitary glands of adult rat to investigate whether grafted RSCs can be induced by the native gland to acquire pituitary properties. Grafted cells survive for 4 weeks and express Pit-1, GH, FSH, LH, ACTH, TSH and to a lesser extent PRL indicating that inductive influences are operative in vivo as well.

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Aims: Spontaneously hypertensive rats (SHR) exhibit overactive bladder (OAB) symptoms and have an up-regulated calcium sensitizing RhoA/Rho-kinase pathway in their vascular smooth muscle tissues. This study examined the role of RhoA/Rho-kinase pathway in bladder hyperactivity by evaluating the effect of a specific Rho-kinase inhibitor (Y-27632) on SHR bladder function.

Methods: Adult male SHR (n = 9) and their normotensive controls (Wistar-Kyoto; WKY) (n = 8) were anesthetized and the carotid artery cannulated for blood pressure monitoring.

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Physiological aging is a significant risk factor in the on-set of male erectile dysfunction (ED) and an imbalance in factors that modulate cavernosal smooth-muscle tone may play a role in these altered penile hemodynamic mechanisms. To evaluate the association between aging and male erectile function, we monitored neurogenic erectile response and its correlation to systemic arterial pressure changes in old (21-23 months of age) vs young (6-9 months of age) Brown-Norway (BN) rats. We tested the hypothesis that age-associated ED is due to unregulated vasoconstrictive tone, contributed in part by an increased Rho-kinase activity, and that antagonism of Rho-kinase activity attenuates the age-related decline in male erectile function.

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Purpose: We evaluated the morphological, immunological and functional response to small intestinal submucosa grafting of the tunica albuginea to determine its potential as a grafting material for penile surgery.

Materials And Methods: Male New Zealand White rabbits underwent a sham procedure (6) or tunical excision and grafting with small intestinal submucosa (6). The erectile response to the intracavernous vasoactive agents sodium nitroprusside plus a papaverine, phentolamine and prostaglandin E1 combination (Sigma Chemical Co.

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