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J Holliday

Publications and source records attributed to J Holliday.

At least 19 recordsLinked to original sources
PubMed2004

Combined family trio and case-control analysis of the COMT Val158Met polymorphism in European patients with anorexia nervosa.

The high activity Val158 (H) allele of the dopamine-metabolizing enzyme catechol-O-methyltransferase (COMT) was associated with anorexia nervosa (AN) in a recent family trio-based study of patients from Israel. In an attempt to replicate this finding, we performed a combined family trio and case-control study in an European population from seven centers in six different countries (Austria, Germany, Great Britain, Italy [Milan], Italy [Florence], Slovenia, and Spain), together contributing a total of 372 family trios, 684 controls and 266 cases. TDT analyses of high (H) and low (L) alleles in family trios showed that H allele and L allele were each transmitted 101 times (chi(2) = 0, ns). Allele-wise case-control analysis using separate samples simply combined from the centers was also not significant, with the frequencies of the H allele 50% in cases and same in controls. Stratified analysis of data from all centers gave an odds ratio of 0.98 (Cornfield 95% confidence limits 0.78-1.24). Analysis by genotype was likewise not significant (overall chi(2) = 0.42). Because we were not able to support the primary hypothesis that Val158Met is a risk factor for AN, we did not perform secondary analysis of minimum body mass index (mBMI), age at onset or illness subtype (restricting or binge purging anorexia). Overall we found no support for the hypothesis that the Val158 allele of COMT gene is associated with AN in our combined European sample.

Alleles↗
PubMed2001

Reducing risk for cardiovascular disease in uninsured women: combined results from two WISEWOMAN projects.

OBJECTIVE: to evaluate the effectiveness of a cardiovascular disease (CVD) risk factor reduction program for financially disadvantaged women. The program included cholesterol and blood pressure assessments and tailored physical activity and nutrition interventions. METHODS: Women who attended selected National Breast and Cervical Cancer Early Detection Program sites in North Carolina and Massachusetts received either enhanced physical activity and nutrition interventions (EI) or minimum interventions (MI). The effectiveness of EI was assessed by pooling data from the North Carolina and Massachusetts projects after 1 year, and a mixed models analysis of covariance was used to compare changes in CVD risk factors across groups. RESULTS: The blood pressure, total cholesterol, and high-density lipoprotein cholesterol profiles of both groups improved, body weight was maintained, and smoking declined. The 10-year estimated coronary heart disease death rate (per 1,000 women) at baseline was 64.8 for the El group and 61.9 for the MI group. The rate declined by 3.5 deaths per 1,000 for the EI and 0.7 per 1,000 for the MI. Although the decline was statistically significant for the EI group, the difference between groups was not significant. CONCLUSION: Further lifestyle intervention research targeting financially disadvantaged women is needed.

Adult↗
PubMed2000

Has the mammography quality standards act affected the mammography quality in North Carolina?

OBJECTIVE: The United States Food and Drug Administration implemented federal regulations governing mammography under the Mammography Quality Standards Act (MQSA) of 1992. During 1995, its first year in implementation, we examined the impact of the MQSA on the quality of mammography in North Carolina. MATERIALS AND METHODS: All mammography facilities were inspected during 1993-1994, and again in 1995. Both inspections evaluated mean glandular radiation dose, phantom image evaluation, darkroom fog, and developer temperature. Two mammography health specialists employed by the North Carolina Division of Radiation Protection performed all inspections and collected and codified data. RESULTS: The percentage of facilities that met quality standards increased from the first inspection to the second inspection. Phantom scores passing rate was 31.6% versus 78.2%; darkroom fog passing rate was 74.3% versus 88.5%; and temperature difference passing rate was 62.4% versus 86.9%. CONCLUSION: In 1995, the first year that the MQSA was in effect, there was a significant improvement in the quality of mammography in North Carolina. This improvement probably resulted from facilities' compliance with federal regulations.

Mammography↗
PubMed2000

Calcium-induced calcium release from intracellular stores is developmentally regulated in primary cultures of cerebellar granule neurons.

The properties of depolarization-evoked calcium transients are known to change during the maturation of dissociated cerebellar granule neuron cultures. Here, we assessed the role of the calcium-induced calcium release (CICR) mechanism in granule neuron maturation. Both depletion of intracellular calcium stores and the pharmacological blockade of CICR significantly reduced depolarization stimulated calcium transients in young but not older (>/=1 week) cultures. This functional decrease in the CICR signaling component was associated with the reduction of ryanodine receptor (RyR) immunoreactivity during granule neuron maturation both in culture and in the intact cerebellum. These observations are consistent with the idea that changes in RyR expression result in functional changes in calcium signaling transients during normal neuronal development in the intact mammalian cerebellum as well as in reduced neuronal cultures. Pharmacological disruption of CICR during neuron differentiation in vitro resulted in dose-dependent changes in survival, GAP-43 expression, and the acquisition of the glutamatergic neurotransmitter phenotype. Together, these results indicate that CICR function plays a physiologically relevant role in regulating early granule neuron differentiation in vitro and is likely to play a role in cerebellar maturation.

Animals↗
PubMed1996

IL-12 expression in AIDS-related lymphoma B cell lines.

IL-12 is a 70-kDa heterodimer formed by the 40-kDa heavy chain (p40) and the 35-kDa light chain (p35). Twenty-five Burkitt's lymphoma cell lines (CL) and seven normal lymphoblastoid B CL were studied. The Burkitt's CL included AIDS-associated B CL (AABCL) (7 EBV+/2 EBV-) and non-AABCL (8 EBV+/8 EBV-). Reverse transcription-PCR detected p40 in EBV+ AABCL (7 of 7), EBV+ non-AABCL (3 of 8), and normal lymphoblastoid B CL (6 of 6) but not in EBV- CL (0 of 10). p35 mRNA was detected in 30 of 30 CL. Constitutive secretion of p40 was found in 7 of 7 EBV+ AABCL (range, 341-18,086 pg/ml) and p70 in 3 of 7 EBV+ AABCL (range, 25-197 pg/ml), but in only 1 of 8 EBV+ non-AABCL and 0 of 7 normal lymphoblastoid CL. PMA stimulated p40 secretion in 7 of 7 EBV+ AABCL and p70 secretion in 5 of 7 EBV+ AABCL. PMA also triggered p40 and p70 secretion in 2 EBV+ non-AABCL and in 3 of 7 normal lymphoblastoid CL. No IL-12 secretion was detected in 10 EBV- CL, including EBV- AABCL. The CL produced IL-10, a known inhibitor of IL-12, but anti-IL-10 Abs did not neutralize IL-12. Similarly, neutralizing anti-IFN gamma Abs or IFN gamma did not affect B cell IL-12. For IL-12R studies, reverse transcription-PCR and 125I-IL-12 binding assays were performed. Although all CL tested showed mRNA accumulation for one of the IL-12R components, IL-12 binding sites were detected in only 1 of 30 CL. Our data suggest that: 1) AABCL constitutively secrete large amounts of IL-12, contrasting with low IL-12 production by HIV-1 infected PBMC; 2) lack of IL-12 expression in EBV- AABCL suggests that in vivo exposure of B cells to HIV-1 only does not induce IL-12 secretion and that both HIV-1 and EBV are required; 3) the autocrine-negative effect of IL-10 on IL-12 in monocytes and the enhancing effect of IFN gamma on IL-12 secretion do not apply to B cells derived from AIDS patients.

Acquired Immunodeficiency Syndrome↗
PubMed1996

Immortalized cerebellar cells can be induced to display mature neuronal characteristics.

We have established and characterized a cell line (designated Cb-E1A) that can be induced to display a variety of neuronal characteristics under simple culture conditions. This cell line was generated by retroviral-mediated gene transfer of the adenovirus 12S E1A-immortalizing gene in cerebellar cells isolated from one-week-old rats. Actively dividing cells express the E1A adenovirus protein, and exhibit minimal expression of glial cell markers and low level expression of neuronal cell markers. The immortalized cells can be induced to differentiate by culture in an alternative depolarizing medium or calcium ionophore-containing medium. This caused the expression of neuronal markers to increase rapidly, while glial markers remain unchanged. Under these culture conditions, the Cb-E1A cells also display a variety of other characteristics which suggest that they may provide a good model system for differentiated cerebellar granule neurons. Such neuronal characteristics include a reduction or cessation of mitosis and an increased susceptibility to glutamate toxicity. We think that this novel cell line and differentiation strategy will facilitate future studies of the cellular mechanisms involved in a wide variety of neuronal functions, including development and neurodegenerative disease.

Animals↗
PubMed1995

Cerebellar granule neurons develop elevated calcium responses when treated with interleukin-6 in culture.

In humans, elevated levels of cytokines are associated with several diseases (including HIV infection and Down Syndrome) that result in developmental abnormalities. Overexpression of interleukin-6 (IL-6) in the central nervous system has been shown to cause extensive neuronal abnormality in mice that becomes more evident with maturation. However, it is difficult to separate direct effects of IL-6 on the developing neurons of an intact animal from indirect effects involving effects on other cell types that possess cytokine receptors, such as microglia and astrocytes. We have found that IL-6 treatment of rat cerebellar granule neurons developing in the absence of other cell types in culture results in the persistence of large, depolarization or neurotransmitter-induced calcium transients, that are normally observed only in immature neurons. The cause of this appears to be the persistence of a calcium-induced calcium release (CICR) component of the calcium response to stimulation. This basic abnormality in neuronal development may contribute to the developmental abnormalities associated with human syndromes that involve elevated cytokine levels.

Age Factors↗
PubMed1994

Quantifying aspiration in scintigraphic deglutition testing: tissue attenuation effects.

UNLABELLED: Scintigraphic studies for determining aspiration associated with swallowing have ignored error due to differential gamma attenuation in the patient by the various regions of the body. This study sought to estimate the magnitude of that error, and to assess the feasibility of providing individual attenuation corrections based on clinical data. METHODS: Relative attenuation for the pharynx, thorax and abdomen were determined from physical measurements employing an anthropomorphic phantom and 45 adult human subjects. A small sealed radioactive source of 2.5 mCi of 99mTc was placed inside the phantom at various locations within the upper digestive tract and respiratory system, and relative count rates determined via static scans with a gamma camera. Similar data for human subjects was obtained from clinical swallowing testing using a bolus of 2.5 mCi of 99mTc in 10 cc of water. RESULTS: The ratios representing relative counts were highly similar between the phantom and average human data. Test-retest replication of results was good for the abdominal reference and pharynx ratios--less so for the thorax. A procedure is described for estimating accuracy of percent aspiration calculation based on group data, using normalization coefficients derived for separate anatomical regions in the subglottic respiratory system. CONCLUSIONS: Error in percent aspiration calculation will depend on the amount and location of aspirate. Individual subject corrections based on the type of clinical data studied should be attempted with caution.

Adult↗
PubMed1993

Calcium dependence of differentiation of GABA immunoreactivity in spinal neurons.

The developmental regulation of neurotransmitter synthesis has been extensively studied and appears in many cases to depend on electrical activity. The central nervous system of the Xenopus embryo and young larva is an attractive subject for such studies, since action potentials first elicited from Xenopus spinal neurons at the time of closure of the neural tube are long in duration and calcium-dependent. Moreover, cells exhibit spontaneous elevations of intracellular calcium during this early period as a consequence of calcium influx through voltage-dependent channels, which induces calcium release from intracellular stores. Since the early differentiation of Xenopus spinal neurons in dissociated cell culture parallels development in vivo, we have examined the maturation of gamma-aminobutyric acid (GABA) immunoreactivity in cultured neurons and explored its dependence on spontaneous calcium influx at early stages of development. We find that specific GABA immunoreactivity develops in spinal neurons in dissociated cell culture with the same time course previously defined in vivo. Additionally, this process requires calcium influx that occurs spontaneously through voltage-dependent channels. The appearance of GABA immunoreactivity is blocked by transcriptional inhibitors. The early appearance of GABA raises the possibility that it may play additional roles at early stages of development.

Animals↗
PubMed1993

Cytokine stimulation increases intracellular calcium and alters the response to quisqualate in cultured cortical astrocytes.

Cytokine levels are elevated in the central nervous system (CNS) in a variety of disorders and may contribute to abnormalities in CNS function associated with the disorders. To begin to understand the mechanisms through which elevated cytokines affect CNS cells, we have examined the effects of cytokines on astrocyte physiology within minutes of application as well as 24 h later. Both standard cultured cortical astrocytes and those induced to further differentiate by pre-treatment with forskolin were examined. Such treated astrocytes may more closely resemble those in brains exhibiting elevated cytokine levels. The cytokine focused upon was interleukin-1-beta (II-1 beta). Gamma-interferon (gamma-IFN) and tumor necrosis factor-alpha (TNF-alpha) were also examined in some studies. Changes in calcium levels produced by acute application of these cytokines were measured. The most pronounced effect was an immediate calcium elevation in response to II-1 beta in the forskolin pre-treated astrocytes. Longer term treatment with IL-1 beta in forskolin pre-treated astrocytes enhanced the calcium response to quisqualate stimulation, a glutamate neurotransmitter receptor agonist. These results suggest that situations that cause chronic changes in cytokine levels and involve astrocytic differentiation, such as chronic CNS infection or Alzheimer's disease, could change astrocytic responses to normal stimuli. Such changes may result in altered astrocytic support of neurons and therefore cause changes in CNS function.

Animals↗
PubMed1993

Calcium regulates neuronal differentiation both directly and via co-cultured myocytes.

Control of neuronal development by cellular interactions can be regulated by both extracellular and intracellular calcium. Removal of extracellular calcium affects the differentiation of amphibian spinal neurons in vitro by preventing neuronal calcium influx during the production of calcium-dependent action potentials (Holliday and Spitzer, Dev. Biol. 141:13-23, 1990). However, this culture condition affects differentiation through other mechanisms as well. We have investigated the interaction between neurons and myocytes to distinguish direct effects of low extracellular calcium on neuronal differentiation and indirect effects due to interference with neuron-myocyte interactions. We have examined the initiation of neurite outgrowth and the subsequent extension and orientation of processes. We find that (1) the number of neurons that initiate process outgrowth is reduced by the presence of myocytes in a standard medium containing calcium. Experiments with muscle-conditioned medium indicate that the production and/or secretion of inhibitory cues is calcium dependent. (2) When neurite initiation occurs, neuronal architecture in the absence of myocytes is similar to that in their presence, either in standard or in calcium-free medium, although neurite extension is enhanced by the absence of calcium. (3) Conditioned medium (CM) experiments additionally demonstrate that the orientation of neurite outgrowth to myocyte-derived cues is calcium dependent, although the production of directional cues by myocytes is calcium independent.

Animals↗
PubMed1991

Inhibition of herpes simplex virus types 1 and 2 replication in vitro by mercurithio analogs of deoxyuridine.

The in vitro antiviral activity of several 5-mercurithio analogs of 2'-deoxyuridine (dUrd) on the replication of herpes simplex virus types 1 (HSV-1) and 2 (HSV-2) were examined. Of those compounds tested, the thioglycerol analog of 5-mercuri-2'-deoxyuridine (HgdUrd) was most effective in inhibiting the replication of HSV-1 in KB cells with a 50% inhibitory dose (ID50) of 0.001 micrograms/ml while the glutathione analog of HgdUrd was the most effective in inhibiting the replication of HSV-2 with a ID50 of 0.075 micrograms/ml. Conversely in HeLa TK- cells, the mercaptoguanosine analog of HgdUrd was the most effective compound in inhibiting virus replication with ID50S of 0.098 and 0.001 micrograms/ml for HSV-1 and HSV-2 respectively. These results suggest that these mercurithio analogs of dUrd are as effective as acyclovir in preventing the replication of these herpesviruses.

Antiviral Agents↗
PubMed1991

Calcium-induced release of calcium regulates differentiation of cultured spinal neurons.

Voltage-dependent calcium influx has been shown to regulate the differentiation of cultured amphibian spinal neurons. We have examined the transient elevation of intracellular calcium induced by depolarization, using calcium indicators and confocal microscopy with high temporal and spatial resolution. Rapid calcium elevations in both the nucleus and the cytosol are primarily due to calcium-dependent release of calcium from intracellular stores. Depletion of stores associated with the endoplasmic reticulum reduces all transients. Elevations diminish with neuronal maturation. Depletion of stores of intracellular calcium at early times affects neuronal differentiation in a manner similar to the prevention of influx. The results indicate that both influx and release are necessary to promote neuronal differentiation.

Animals↗
PubMed1990

Spontaneous calcium influx and its roles in differentiation of spinal neurons in culture.

Stimulation of embryonic amphibian spinal neurons has been shown to produce calcium-dependent action potentials of long duration at early stages of development. These impulses become brief and sodium-dependent upon further differentiation. The neurons are now shown to exhibit spontaneous, transient elevations of intracellular calcium in culture during the early developmental period when activity produces greatest calcium influx. Removal of extracellular calcium during this period alone is sufficient to perturb differentiation, and influx through voltage-dependent calcium channels is shown to be required for standard development of neuronal phenotypes. No large changes in steady-state calcium levels occur in the cytoplasm during the maturation of cultured neurons despite a reduction of the calcium-dependent component of the impulse. Transient elevation of intracellular calcium is necessary for standard cytodifferentiation and may provide a link between electrical activity and gene expression.

Action Potentials↗
PubMed1987

Monoclonal antibodies with defined specificities for Torpedo nicotinic acetylcholine receptor cross-react with Drosophila neural tissue.

A panel of monoclonal antibodies with known specificity for the well-characterized nicotinic acetylcholine receptor from the electroplax of Torpedo californica, many of which cross-react with the mammalian muscle acetylcholine receptor, were examined for cross-reactivity in the fly, Drosophila melanogaster. Monoclonal antibodies with specificities for different epitopes on the transmembrane receptor complex from Torpedo cross-react with different regional subsets of neural tissue in Drosophila. Axonal tracts, neuropil, mechano-sensory bristle elements and photoreceptors, each are detected by separate monoclonal antibody classes corresponding to different epitope domains. A preliminary characterization of an antigenic determinant in Drosophila heads recognized by one of the cross-reacting monoclonal antibodies is presented. Monoclonal antibodies such as these may be useful in identifying molecules of homologous structure or function, possibly including a neuronal acetylcholine receptor.

Animals↗
PubMed1987

Immunohistochemical localization of a neuronal nicotinic acetylcholine receptor in mammalian brain.

A monoclonal antibody generated against purified acetylcholine receptor from Torpedo electric organ was used to immunohistochemically localize a neuronal nicotinic acetylcholine receptor. Regions of the rat brain stained with this antibody paralleled those areas of the brain exhibiting [3H]nicotine binding sites and corresponded to areas in which mRNAs encoding for alpha subunits of the neuronal nicotinic acetylcholine receptor are present. Thus, the anteroventral thalamus, cortex, hippocampus, medial habenula, interpeduncular nucleus, and substantia nigra/ventral tegmental area exhibited significant immunoreactivity. Neurons of the medial habenula and substantia nigra were densely stained, and processes were prominently delineated. Furthermore, in the projection areas of the medial habenula (interpeduncular nucleus and median raphe) axons were strongly immunoreactive and were distributed to distinct subdivisions of the target sites. The present data suggest that there are several discrete neuronal systems in which nicotinic acetylcholine receptors have functional importance. These immunohistochemical studies delineate at the single-cell level the localization within the mammalian central nervous system of certain nicotinic acetylcholine receptors.

Animals↗