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J Jones

Publications and source records attributed to J Jones.

At least 145 records · Page 8Linked to original sources
PubMed2000

Transcriptional repression by AtMYB4 controls production of UV-protecting sunscreens in Arabidopsis.

An Arabidopsis thaliana line that is mutant for the R2R3 MYB gene, AtMYB4, shows enhanced levels of sinapate esters in its leaves. The mutant line is more tolerant of UV-B irradiation than wild type. The increase in sinapate ester accumulation in the mutant is associated with an enhanced expression of the gene encoding cinnamate 4-hydroxylase, which appears to be the principal target of AtMYB4 and an effective rate limiting step in the synthesis of sinapate ester sunscreens. AtMYB4 expression is downregulated by exposure to UV-B light, indicating that derepression is an important mechanism for acclimation to UV-B in A.thaliana. The response of target genes to AtMYB4 repression is dose dependent, a feature that operates under physiological conditions to reinforce the silencing effect of AtMYB4 at high activity. AtMYB4 works as a repressor of target gene expression and includes a repression domain. It belongs to a novel group of plant R2R3 MYB proteins involved in transcriptional silencing. The balance between MYB activators and repressors on common target promoters may provide extra flexibility in transcriptional control.

Arabidopsis↗
PubMed2000

Longitudinal analysis of symptoms reported by patients with chronic fatigue syndrome.

PURPOSE: To determine the effect of chronic fatigue syndrome (CFS) illness duration and onset type on the likelihood of reporting a symptom during successive follow-up periods.METHODS: In 1997, a two-phase RDD survey in Wichita, Kansas, was conducted to estimate the prevalence of CFS. Phase I identified 56,154 respondents 18-69 years of age and screened for severe fatigue, extreme tiredness or exhaustion lasting for 1 month or longer. In phase II an equal number of fatigued (n = 7,176) and randomly selected non-fatigued subjects were asked about 8 CFS and 13 non-CFS symptoms, as well as the presence of specific medical and psychiatric conditions. Eligible respondents were clinically evaluated to establish CFS diagnosis. Phase II respondents were re-contacted at 12- (n = 4,331) and 24-months (n = 4,266) for additional follow-up and diagnosis. In this study we considered symptoms reported as being present most of the time during each successive observation period. Generalized estimating equations were used to model symptoms over time and to address study questions. Such a model accounts for correlations among repeated symptoms for each subject. We used an auto-regressive structure for the correlation matrix, assuming the correlations between each pair of repeated symptoms should decrease as the time between symptoms increased.RESULTS: There were 74 CFS patients who had been ill for 1 to 20 years (median = 6.3 years). Among these, 46 reported gradual and 28 reported sudden onset. Symptoms fluctuated over the course of illness. However, only stomach pain (non-CFS symptom) was more likely to be reported as duration of illness increased (p < 0.05). There was no association between onset type and the likelihood of reporting a symptom during an interview, except that chills and severe headaches were more likely to be reported by sudden cases.CONCLUSIONS: The likelihood of expressing CFS and non-CFS symptom "most of the time" is the same across years of illness. More analyses are warranted to consider expression of symptoms for >/=6 months and severe symptoms.

Journal Article↗
PubMed2000

1-[2-[(Heteroaryloxy)heteroaryl]carbamoyl]indolines: novel and selective 5-HT2C receptor inverse agonists with potential as antidepressant/anxiolytic agents.

Bisaryl ethers have been identified with excellent 5-HT2C affinity and selectivity over both 5-HT2A and 5-HT2B receptors. Compounds such as 11, 27 and 38 have potent oral activity in a centrally mediated pharmacodynamic model of 5-HT2C function and their potential as novel non-sedating anxiolytic and antidepressants is under investigation.

Administration, Oral↗