National Jewish Health

About: National Jewish Health is a healthcare organization based out in Denver, Colorado, United States. It is known for research contribution in the topics: T cell & Asthma. The organization has 883 authors who have published 833 publications receiving 79201 citations. The organization is also known as: National Jewish Medical and Research Center.

Targeted over-expression of mPGES-1 and elevated PGE2 production is not sufficient for lung tumorigenesis in mice

Abstract: There is a significant body of evidence suggesting that enzymes involved in arachidonic acid metabolism and their eicosanoid products play a role in various cancers, having both pro- and antitumorigenic effects. The goal of this study was to further define the role microsomal prostaglandin E synthases (mPGES-1) play in lung tumorigenesis. Transgenic mice were created with targeted over-expression of human mPGES-1 in the alveolar and airway epithelial cells using an SP-C promoter driven construct. Transgene positive (mPGES-1 + ) mice were shown to significantly over-express functional mPGES-1 in the lung and more specifically in alveolar type II cells. To study the effects of mPGES-1 over-expression in lung tumor formation, mice were exposed to a complete carcinogen protocol with a single injection of urethane or an initiation/promotion model with a single injection of 3-methyl-cholanthrene (MCA) followed by multiple injections of butylated hydroxytoluene (BHT). mPGES-1 + mice did not show a significant difference in tumor multiplicity or tumor size at 10, 16, 19 or 30 weeks after urethane injection compared with mPGES-1 - mice. No significant difference was seen in tumor incidence, multiplicity or size at 19 weeks after treatment with MCA/BHT. Western blots verified that mPGES-1 expression was increased in tumors versus uninvolved tissue of both mPGES-1 + and mPGES-1 - mice with overall expression being significantly higher in mPGES-1 + mice. Cyclooxygenase-2 levels were elevated in tumors in both groups. From these studies we conclude that over-expression of mPGES-1 and highly elevated PGE 2 production are not sufficient to induce lung tumors.

Comparison of actigraphy immobility rules with polysomnographic sleep onset latency in children and adolescents

Abstract: Purpose While actigraphy has gained popularity in pediatric sleep research, questions remain about the validity of actigraphy as an estimate of sleep-wake patterns In particular, there is little consistency in the field in terms of scoring rules used to determine sleep onset latency The purpose of this study was to evaluate different criteria of immobility as a measure of sleep onset latency in children and adolescents

Inhibition of specific immune responses by feeding protein antigens. V. Induction of the tolerant state in the absence of specific suppressor T cells.

Abstract: The effect of CY pretreatment on the ability of OVA feeding to induce both tolerance and active suppression was examined in mice. CY-pretreated, OVA fed mice were fully unresponsive in both OVA-specific DTH and antibody responses, but, in contrast to untreated OVA-fed mice, did not transfer suppression to normal recipients via splenic lymphocytes. Restoration of Ts activity in CY-pretreated mice was accomplished by reconstitution with normal T cells before antigen feeding, indicating that the CY effect was at the Ts precursor level. In addition, it was found that certain OVA-specific immune parameters (DTH and splenic PFC responses) in recipient mice were susceptible to suppression by transfer of spleen cells from OVA-fed donors, whereas other measures (antigen-induced T cell proliferation and serum antibody titers) were not. The data suggest that CY-sensitive Ts are not necessary for either induction or maintenance of specific tolerance after OVA feeding.