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Biomedical subjects

J F Moore

Publications and source records attributed to J F Moore.

At least 19 recordsLinked to original sources
PubMed2001

Antiferrodistortive reconstruction of the PbTiO(3)(001) surface.

We present in situ x-ray scattering measurements of the surface structures of PbTiO(3) (001) in equilibrium with PbO vapor. At 875 to 1025 K, a reconstruction having c(2x2) symmetry is present under most conditions, while a 1 x 6 reconstruction occurs under PbO-poor conditions. The atomic structure of the c(2x2) phase is found to consist of a single layer of an antiferrodistortive structure with oxygen cages counter-rotated by 10 degrees about the titanium ions.

Journal Article↗
PubMed2000

Cocaine inhibits NGF-induced PC12 cells differentiation through D(1)-type dopamine receptors.

In utero cocaine exposure can adversely affect CNS development. Previous studies showed that cocaine inhibits neuronal differentiation in a dose-dependent fashion in nerve growth factor (NGF)-stimulated PC12 cells. Cocaine binds with high affinity to several neurotransmitter transporters, resulting in elevated neurotransmitter levels in nerve endings. To determine if cocaine inhibits neurite outgrowth through the effects of these neurotransmitters, we applied dopamine, norepinephrine, serotonin, and acetylcholine to NGF-induced PC12 cells. Dopamine was the only neurotransmitter to inhibit neurite outgrowth significantly in a dose-dependent pattern without affecting cell viability. Norepinephrine and acetylcholine did not affect neurite outgrowth, while serotonin enhanced it. Furthermore, GBR 12909, a potent dopamine transporter (DAT) inhibitor, yielded similar effects. We then showed PC12 cells express D(1) and D(2) receptors and DAT proteins. Dopamine uptake measured over time was significantly blocked by cocaine and GBR 12909 which may result in elevated extracellular dopamine. The role of dopamine receptors in PC12 differentiation was further examined by using D(1) and D(2) specific receptor agonists. Only the D(1) agonist, SKF-38393, had a significant dose-dependent inhibitory effect. In addition, a D(1) antagonist produced significant recovery of neurite outgrowth in cocaine-treated cells. These findings suggest that cocaine inhibitory effects on neuronal differentiation are mediated through its binding to the dopamine transporter, resulting in increased dopamine level in the synapses. Subsequently, up regulation of D(1) receptors alters NGF signaling pathways.

Animals↗
PubMed2000

Cocaine inhibition of neuronal differentiation in NGF-induced PC12 cells is independent of ras signaling.

In utero exposure to cocaine may result in altered neuronal development. Our previous studies demonstrated cocaine inhibits neurite outgrowth in NGF-induced PC12 cells through dopamine, by activation of D1 receptors. This study examined where cocaine interferes in the NGF signaling cascade. GSrasl cells that inducibly express activated forms of Ras upon treatment with dexamethasone were used. Morphological differentiation was quantified by counting cells bearing neurite-like processes after 72 h exposure to either dexamethasone or NGF alone, or with cocaine, dopamine or SKF-38393. Cocaine, dopamine, and the D1 agonist inhibited neurite-like process outgrowth in both dexamethasone and NGF-induced GSras1 cells. GAP-43 expression, used as a measure for biochemical differentiation was severely diminished in NGF and dexamethasone-induced GSras1 cells treated with cocaine. These results suggest that cocaine, dopamine and activation of D1 receptors affect the NGF signaling downstream, independent of ras expression, leading to altered neuronal differentiation.

2,3,4,5-Tetrahydro-7,8-dihydroxy-1-phenyl-1H-3-ben↗
PubMed2000

Perinatal care: cultural and technical differences between China and the United States.

A comparison of perinatal care in the U.S. and China is presented. Perinatal care has made tremendous achievements in both countries since mid-century. However, the outcomes in the two cultures are different due to the different focus on caring concepts, the strengths of a nursing philosophy, and the emphasis on the nursing role in maternal care. Perinatal family in the U.S. will have advantages in perinatal education physical facilities, and a philosophy of care. North American women have greater access to early prenatal and continuing care, and less infant mortality. Chinese women have less access to qualified nursing services, higher infant mortality rates, and limited perinatal education. Overall, Chinese perinatal care is far behind that which is found in the U.S. This comparison analyzes the strengths and weaknesses in both cultures with a focus on change that will produce healthier and more consistent optimal outcomes.

China↗
PubMed1998

C-fos mediates cocaine inhibition of NGF-induced PC12 cell differentiation.

In utero cocaine exposure can affect CNS development. Previous studies showed that cocaine inhibits neuronal differentiation in a dose-dependent fashion, in nerve growth factor (NGF)-stimulated PC12 cells, without affecting cell viability. NGF activates intracellular signaling proteins, specific immediate-early genes (IEG) including a transient peak of c-fos expression, and induction of late genes expression, leading to the neuronal phenotype. We hypothesized that cocaine interferes with NGF signaling. Therefore, we examined the pattern of c-fos expression in our cellular model. Time course of c-fos expression up to 72 h was determined in cells treated with NGF 20 ng/ml and cocaine 10 microgram/ml (a moderately toxic level) by RT-PCR analysis. Total RNA was isolated from cells, and levels of c-fos mRNA were estimated using gene-specific primers. In both control and experimental conditions, c-fos level was maximal at 0.5 h. In the control cells, c-fos expression declined rapidly to less than 5% of the 0.5h value, while in the cocaine-treated cells, c-fos level persisted through the 72-h exposure. Adding c-fos antisense to cells treated with NGF and cocaine resulted in significant improvement of neurite out-growth, from 28% (NGF + cocaine) to 89% (NGF + cocaine + c-fos antisense) of control differentiation after 72 h of exposure (Dunnet's T < 3.24). Inhibitory effects of cocaine on NGF-induced PC12 differentiation may be attributed to alteration of c-fos expression. Further studies will be required to examine the role of D1 receptor activation in mediating c-fos expression and to explore the effects of cocaine on other IEGs.

Animals↗
PubMed1996

Inhibitory effects of cocaine on NGF-induced neuronal differentiation: incomplete reversibility after a critical time period.

We extend our findings showing dose-dependent cocaine inhibition of differentiation in NGF-stimulated PC-12 cells without affecting cell viability by demonstrating that neurite extension is severely limited after 24 h, maximal effect is reached at 36 h and recovery is only partial. Cocaine metabolites lack these effects. A similar process may occur following human prenatal exposure, perhaps through cocaine-induced changes in gene expression or other intracellular signalling events.

Animals↗
PubMed1996

Patients' health problems: differences in perceptions between home health patients and nurses.

Quality care is consumer-driven care. Yet, much of home healthcare is driven by Medicare regulations and reimbursement rates. This study compared home health patients' perceptions of their health problems with nurses' documentation of the patients' health problems. The results showed that the problems patients report and nurses document are very different. Home health nurses must move beyond a focus on medicare-reimbursable patient problems to documenting and providing consumer-driven patient care.

Aged↗
PubMed1995

Novel use of limited primer extension in detecting mutations in human iduronate 2-sulfatase gene.

Hunter syndrome is characterized by a deficiency of iduronate 2-sulfatase. A large number of mutations in the gene have been reported. We describe here the development of a limited primer method for the identification of mutations. In the reaction mixture designed for the limited primer extension, one or two deoxynucleotides from the four necessary deoxynucleotides are added as "selected nucleotides" and another deoxynucleotide which is radiolabeled is added as the "limited nucleotide". The absence of one or two of the deoxynucleotides limits the length of primer elongation, and the low concentration of the "limited nucleotide" causes an "extension-delay" effect and results in a banding pattern upon electrophoresis of the products thus making it possible to distinguish mutant and normal alleles. We have studied three novel mutations in exon IX, 407delTT (TTT to T), 423insCC (CCC to CCCCC), and W502X (TGG to TAG) of the iduronate 2-sulfatase gene by the limited primer extension method.

Base Sequence↗
PubMed1994

Choline deficiency in cultured adrenal medullary cells: effect on phosphatidylcholine biosynthesis.

The effect of choline deficiency on the composition and biosynthesis of the major membrane phospholipids was examined in adrenal medullary cells maintained in suspension cultures. The amount and proportions of phosphatidylcholine (PC) and phosphatidylethanolamine (PE) in these cells were not affected by the removal of choline from the culture media. However, the rate of biosynthesis of choline at the phosphatide level by the stepwise methylation of PE increased twofold within 24 h after choline was removed from the culture media, while ethanolamine incorporation into PE was increased by 50%. In contrast, the rate of incorporation of labeled choline into PC, presumably via CDP-choline, was virtually identical in cells that had been preincubated in the presence or absence of 1 mM choline. These results demonstrate that cultured cells of neural origin are capable of compensating for lack of exogenous choline by forming choline at the phosphatide level through the sequential methylation of PE. The hypolipidemic drug, DH-990, when added to the culture media, inhibited conversion of phosphatidylmonomethylethanolamine (PME) to PC, but had no effect on the N-methylation of PE. This differential effect indicates that the initial N-methylation of PE is catalyzed by an enzyme that is distinguishable from the enzyme(s) catalyzing the conversion of PME to PC.

Adrenal Medulla↗
PubMed1993

Efficacy of a home-based human immunodeficiency virus prevention video program for teens and parents.

Family-based communication about sexual behavior and sexuality is a predominate theme in the key risk reduction and service objectives for human immunodeficiency virus (HIV) prevention and related issues in Healthy People 2000. These recommendations are particularly poignant for younger adolescents who are not yet sexually active and whose social orientation is primarily to family and parents. A family-centered, home-based, video program to foster parent and teen knowledge and communication regarding issues related to HIV prevention and to increase family and teen communication skills was used in an intensive field test of program efficacy. Sixty-nine families with at least one adolescent age 12 to 14 years were recruited through their primary-care physicians and were randomly assigned to either experimental (video with information and skills training) or control (video with information only) conditions in a pre-posttest with a 4-month follow-up design. Both versions of the video program resulted in substantial increases in HIV-related knowledge for parents and teens, but only the skill-training (experimental) version produced increases in knowledge of communication skills and behavioral demonstrations of family problem solving. Approaches for a broader and more effective parent-training video program and for dissemination through primary-care physicians are discussed.

Adolescent↗
PubMed1992

Family/media approach to HIV prevention: results with a home-based, parent-teen video program.

We describe the first study with a home-based HIV prevention video program for parents and young teenagers. The objectives of the program are to inform parents and teenagers about the causes and prevention of HIV infection and other sexually transmitted diseases, to increase family problem-solving skills, and to increase teen problem-solving and assertiveness skills. The objectives pertain to the goals of increasing skills needed to help teenagers avoid or manage high-risk behaviors and situations. Forty-five families with at least one 12- to 14-year-old were randomly assigned to either experimental (receive video program) or control (no video) conditions in a pretest-posttest design. After 6 months (Follow-Up 1), the experimental and control families were reassessed. The control families next received the video program, and the control families were assessed again (Follow-Up 2). The results indicate increases in parent and teen knowledge and skills only with video viewing. Approaches to improving the video program, particularly with teenagers, are discussed.

Acquired Immunodeficiency Syndrome↗
PubMed1991

Phosphoglyceride biosynthesis in bovine adrenal chromaffin cells.

Cultured adrenal chromaffin cells, representing a virtually homogeneous population of neuronal elements, have been utilized to examine the final enzymes in the formation of phosphatidylcholine (PC) and phosphatidylethanolamine (PE), namely, choline phosphotransferase, ethanolaminephosphotransferase, and the N-methyltransferases in the sequential methylation of PE to PC. Each enzyme has been characterized extensively in terms of substrate requirements, pH optima, detergent and cation effects, and response to inhibitors revealing properties very similar to those in other neural preparations. The respective activities are stable for up to two weeks of adrenal chromaffin cell culture suggesting that this system is a suitable model for examining the relative roles and the regulation of each pathway in PC formation.

Adrenal Medulla↗
PubMed1991

An experimental evaluation of a prototype public access nutrition information system for supermarkets.

Located the Nutrition for a Lifetime System (NLS-1), a prototype interactive information system, in a large supermarket to help users decrease high-fat food purchases and increase high-fiber food purchases. Study participants were randomly assigned to control (n = 23; used the NLS-1 to enter food purchases only) or experimental (n = 26; viewed videodisc instructional programs, received prompts, made commitments, received feedback from the NLS-1) conditions. According to data entered in the NLS-1 and actual food shopping receipts, experimental participants significantly reduced higher fat purchases. Increases in higher fiber purchases favored the experimental group but were not significant.

Adult↗