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Biomedical subjects

G L Allen

Publications and source records attributed to G L Allen.

At least 19 recordsLinked to original sources
PubMed2000

Hyperoxia synergistically increases TNF-alpha-induced interleukin-8 gene expression in A549 cells.

Interleukin (IL)-8 is an important mediator of acute lung injury. Hyperoxia induces IL-8 production in some cell types, but its effect on IL-8 gene expression in respiratory epithelium is not well described. In addition, IL-8 gene expression resulting from the combined effects of hyperoxia and proinflammatory cytokines has not been well characterized. We treated cultured respiratory epithelial-like cells (A549 cells) with hyperoxia alone, tumor necrosis factor (TNF)-alpha alone, or the combination of TNF-alpha and hyperoxia and evaluated IL-8 gene expression. Hyperoxia alone had a minimal effect on IL-8 gene expression, and TNF-alpha alone increased IL-8 gene expression in a time-dependent manner. In contrast, the combination of TNF-alpha and hyperoxia synergistically increased IL-8 gene expression as measured by ELISA (TNF-alpha alone for 24 h = 769 +/- 89 pg/ml vs. hyperoxia + TNF-alpha for 24 h = 1, 189 +/- 89 pg/ml) and Northern blot analyses. Experiments involving IL-8 promoter-reporter assays, electromobility shift assays, and Western blot analyses demonstrated that hyperoxia augmented TNF-alpha-mediated activation of the IL-8 promoter by a nuclear factor (NF)-kappaB-dependent mechanism and increased the duration of NF-kappaB nuclear translocation after concomitant treatment with TNF-alpha. Additional reporter gene assays demonstrated, however, that increased activation of NF-kappaB does not fully account for the synergistic effect of hyperoxia and that the NF-IL-6 site in the IL-8 promoter is also required for the synergistic effect of hyperoxia. We conclude that hyperoxia alone has a minimal effect on IL-8 gene expression but synergistically increases IL-8 gene expression in the presence of TNF-alpha by a mechanism involving cooperative interaction between the transcription factors NF-kappaB and NF-IL-6.

Binding Sites↗
PubMed1996

Aging, cognitive resources, and declarative learning.

A battery of cognitive tasks designed to assess information-processing speed, working memory capability, and declarative learning was administered to a cross-sectional sample of 477 adults ranging in age from 17 to 86 years. Results showed significant age-related decrements in all three constructs. A variety of structural equation models was fit to the results. The preferred model on empirical and conceptual grounds was one that showed (a) working memory capability as the most important mediator of age effects in declarative learning; (b) working memory capability as the mediator for the effects of general processing speed on declarative learning; and (c) differentiation among verbal, numeric, and spatial processing speed and between verbal and spatial working memory capability.

Adolescent↗
PubMed1995

Cardiac tamponade: an unusual feature of adult onset Still's disease.

Adult onset Still's disease (AOSD) is an uncommon, systemic, inflammatory disorder of unknown etiology characterized by the triad of fever, arthritis and rash. We describe 2 cases of cardiac tamponade in patients with AOSD, review reported cases, and describe the features, and therapy of AOSD.

Adult↗
PubMed1994

The role of visual imagery in the retention of information from sentences.

We conducted two experiments to evaluate a multiple-code model for sentence memory that posits both propositional and visual representational systems. Both sentences involved recognition memory. The results of Experiment 1 indicated that subjects' recognition memory for concrete sentences was superior to their recognition memory for abstract sentences. Instructions to use visual imagery to enhance recognition performance yielded no effects. Experiment 2 tested the prediction that interference by a visual task would differentially affect recognition memory for concrete sentences. Results showed the interference task to have had a detrimental effect on recognition memory for both concrete and abstract sentences. Overall, the evidence provided partial support for both a multiple-code model and a semantic integration model of sentence memory.

Adult↗
PubMed1992

The tissue distribution of tumor necrosis factor biosynthesis during endotoxemia.

Tumor necrosis factor (TNF) is a protein hormone implicated in the development of septic shock and other pathologic states. However, complexities inherent in detecting TNF synthesis by individual tissues have left the precise origins of this protein undefined. In addition, the possibility that localized TNF production may contribute to the pathogenesis of organ-specific diseases such as type I diabetes has not been explored in vivo. We have developed a transgenic mouse line bearing a reporter gene construct in which the TNF coding sequence and introns are replaced by a chloramphenicol acetyltransferase (CAT) coding sequence. In normal transgenic animals, CAT activity is expressed only in the thymus. When endotoxin is administered to the animals, CAT activity is also evident in kidney, heart, islets of Langerhans, spleen, lung, fallopian tubes, and uterus, but not in other organs. The biosynthesis of CAT in vivo correlated with tissue capacity to secrete TNF in vitro. Thus, TNF was secreted by all the tissues that expressed CAT, including lung, spleen, thymus, uterus/fallopian tubes, pancreatic islets, renal glomeruli, and cultured cardiac cells after exposure to endotoxin.

Animals↗
PubMed1989

Children's expressions of spatial knowledge.

Different expressions of spatial knowledge were examined by having groups of first-, fourth-, and sixth-grade children perform model construction, verbal description, and route reversal tasks after they learned the correct path through a pedestrian maze. Age-related improvement was found in the rate of learning the maze and in the accuracy of verbal descriptions, suggesting that maze learning may be verbally mediated. All children performed well in sequencing intersections in the model but performed poorly in choosing path options in the model. Route reversal after learning was accurate and equivalent across groups. Overall, results suggest that both general and task-specific skills are involved in different products of spatial knowledge.

Child↗
PubMed1988

Attempts to train novices for beer flavor discrimination: a matter of taste.

Inexperienced beer-drinkers who could not pass a beer-flavor discrimination test were divided into a taste group, which received additional perceptual experience with beer flavors; a verbal group, which received instruction in beer flavor terminology; a taste/verbal group, which received both additional experience and instruction; and a control group. Before and after training, all subjects participated in a similarity rating task involving beer flavors and flavor-related adjectives. Additional taste experience--but not increased experience with beer-flavor terminology--improved novices' ability to detect identical beer flavors. Results are discussed in terms of the trainability of flavor discrimination and the role of cognitive factors (both flavor-related and flavor-independent) in marketing beverages.

Beer↗
PubMed1986

The clinical diagnosis of Reiter's syndrome. Ophthalmic and nonophthalmic aspects.

The histories of 113 patients with Reiter's syndrome were reviewed to obtain information regarding the sequence of the clinical signs and symptoms, laboratory findings, and progression of disease. Rheumatologic manifestations occurred in 98% of the patients, genitourinary manifestations in 74%, ophthalmic manifestations in 58%, and mucocutaneous manifestations in 42%. Four major criteria and six categories of minor criteria for the diagnosis of Reiter's syndrome, based on the frequency and specificity of the various manifestations of the disease, are proposed. The ophthalmic and nonophthalmic features are important to appreciate because the ophthalmologist is frequently at the pivotal point in suggesting or supporting the diagnosis.

Adult↗
PubMed1979

The development of cognitive maps of large- and small-scale spaces.

Kindergartners, second, and fifth graders made repeated trips through a large- or small-scale model town, and then constructed from memory the layout of buildings in either a large- or small-scale space. Accuracy of construction increased as a function of developmental level and repeated trips through the town. Children's constructions were most accurate when they were tested in the same-scale environment as that in which they developed their spatial knowledge; accuracy was impaired significantly only when children were exposed to a small space and then reconstructed in a large space. Results were interpreted in terms of a "competence-load trade-off."

Child↗
PubMed1979

Developmental issues in cognitive mapping: the selection and utilization of environmental landmarks.

2 studies were conducted to investigate developmental differences in the ability to select and use environmental landmarks for cognitively organizing distance information from a walk. In experiment 1, second-grade, fifth-grade, and college subjects viewed a simulated walk and selected scenes that were high in potential landmark value. In experiment 2, children from the same grade levels first viewed the walk and then ranked distances among either the test scenes most frequently selected by their peers or those selected most frequently by adults. Results indicated that (a) adults and children may not spontaneously select the same features as real-world landmarks; (b) children are less capable than adults in judging the value of potential landmarks as distance cues; and (c) the ability to use environmental landmarks as cues for distance information developmentally precedes the ability to assess this potential information value.

Adult↗
PubMed1975

Daily and alternate-day corticosteroid regimens in treatment of giant cell arteritis: comparison in a prospective study.

Alternate-day corticosteroid therapy was compared with two daily corticosteroid regimens for the treatment of giant cell arteritis. In a prospective study 60 patients with this disease were randomly assigned to three treatment groups: group A, 15 mg of prednisone every 8 hours; group B, 45 mg of prednisone every morning; and group C, 90 mgof prednisone every other morning. After 1 month of treatment, the arteritis seemed to be completely suppressed in 18 patients in group A and 16 in group B but in only 6 in group C. In the 14 other patients in group C, the continuing symptoms were cyclic and developed during the day steroids were not given. By changing to a daily regimen, the arteritis was controlled in most patients in group C. Adverse reactions to prednisone were noted frequently in groups A and B but rarely in group C.

Aged↗