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Laura De Pretto Stephen Acreman Matthew J. Ashfold Suresh K. Mohankumar Ahimsa Campos-Arceiz 《PloS one》2015,10(12)
Transboundary haze episodes caused by seasonal forest fires have become a recurrent phenomenon in Southeast Asia, with serious environmental, economic, and public health implications. Here we present a cross-sectional survey conducted among people in Kuala Lumpur and surrounds to assess the links between knowledge, attitudes, and practices in relation to the transboundary haze episodes. Of 305 respondents, 125 were amateur athletes participating in a duathlon event and the remainder were surveyed in an inner-city shopping mall. Across the whole sample, people who possessed more factual information about the haze phenomenon showed significantly higher levels of concern. Duathletes were more knowledgeable than non-duathletes and also more concerned about the negative effects of haze, especially on health. For all people who regularly practice outdoor sports (including people interviewed at the shopping mall), higher levels of knowledge and concerned attitudes translated into a greater likelihood of engaging in protective practices, such as cancelling their outdoor training sessions, while those with greater knowledge were more likely to check the relevant air pollution index on a daily basis. Our results indicate that the provision of accurate and timely information about air quality to residents will translate into beneficial practices, at least among particularly exposed individuals, such as amateur athletes who regularly practice outdoor sports. 相似文献
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In this article, we discuss molecular mechanisms involved in the evolution of amygdala kindling and the episodic loss of response
to pharmacological treatments during tolerance development. These phenomena allow us to consider how similar principles (in
different neurochemical systems) could account for illness progression, cyclicity, and drug tolerance in affective disorders.
We describe the phenomenon of amygdala-kindled seizures episodically breaking through effective daily pharmacotherapy with
carbamazepine and valproate, suggesting that these observations could reflect the balance of pathological vs compensatory
illness-induced changes in gene expression. Under certain circumstances, amygdala-kindled animals that were initially drug
responsive can develop highly individualized patterns of seizure breakthroughs progressing toward a complete loss of drug
efficacy. This initial drug efficacy may reflect the combination of drug-related exogenous neurochemical mechanisms and illness-induced
endogenous compensatory mechanisms. However, we postulate that when seizures are inhibited, the endogenous illness-induced
adaptations dissipate (the “time-off seizure” effect), leading to the re-emergence of seizures, a re-induction of a new, but
diminished, set of endogenous compensatory mechanisms, and a temporary period of renewed drug efficacy. As this pattern repeats,
an intermittent or cyclic response to the anticonvulsant treatment emerges, leading toward complete drug tolerance.
We also postulate that the cyclic pattern accelerates over time because of both the failure of robust illness-induced endogenous
adaptations to emerge and the progression in pathophysiological mechanisms (mediated by long-lasting changes in gene expression
and their downstream consequences) as a result of repeated occurrences of seizures. In this seizure model, this pattern can
be inhibited and drug responsivity can be temporarily reinstated by several manipulations, including lowering illness drive
(decreasing the stimulation current.), increasing drug dosage, switching to a new drug that does not show crosstolerance to
the original medication, or temporarily discontinuing treatment, allowing the illness to re-emerge in an unmedicated animal.
Each of these variables is discussed in relation to the potential relevance to the emergence, progression, and suppression
of individual patterns of episodic cyclicity in the recurrent affective disorders. A variety of clinical studies are outlined
that specifically test the hypotheses derived from this formulation. Data from animal studies suggest that illness cyclicity
can develop from the relative ratio between primary pathological processes and secondary endogenous adaptations (assisted
by exogenous medications). If this proposition is verified, it further suggests that illness cyclicity is inherent to the
neurobiological processes of episode emergence and amelioration, and one does not need to postulate a separate defect in the
biological clock. The formulation predicts that early and aggressive long-term interventions may be optimal in order to prevent
illness emergence and progression and its associated accumulating neurobiological, vulnerability factors. 相似文献
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A partial swine cDNA which encodes the functional domain of PIT-1 was isolated by the polymerse chain reaction (PCR). The swine PIT-1 cDNA clone is 95% identical at the protein level to the rat Pit-1 gene. Thus, Pit-l's known function in control of rat growth hormone and prolactin expression is likely to be conserved in swine. This swine cDNA clone was used to investigate genetic variability at PIT-1 in several American and Chinese breeds. Polymorphic BamIII fragments were found in pure-bred Meishan animals (n= 13), but only monomorphic fragments in five American breeds (n= 36). 相似文献
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D R Hickey K Jayaraman C T Goodhue J Shah S A Fingar J M Clements Y Hosokawa S Tsunasawa F Sherman 《Gene》1991,105(1):73-81
Genes encoding tuna, pigeon, and horse cytochromes c were constructed with synthetic oligodeoxyribonucleotides having preferred codons and portions of the iso-1-cytochrome c-encoding gene from the yeast Saccharomyces cerevisiae. The genes were ligated into an expression vector, which contains the normal 5'- and 3'-untranslated regions of the yeast iso-1-cytochrome c gene, and were integrated in single copy into the chromosome. Yeast strains were also constructed with multiple integrated copies of the pigeon gene. The heterologous and normal mRNA levels of the single-copy strains were equivalent. Although the N-terminal methionines were completely cleaved in the heterospecific proteins, the levels of trimethylation of Lys72 and acetylation of N-terminal glycines ranged from 39-78% and 10-70%, respectively. Horse cytochrome c was produced at a nearly normal level, whereas the pigeon and tuna cytochromes c were produced at approx. 40% of the normal levels. The levels of the cytochromes c and growth of the mutant yeast strains indicated that the heterospecific cytochromes c had approx. 50% specific activity in vivo. 相似文献
10.
The role of the epidermal growth factor-1 and hydrophobic stack domains of human factor IX in binding to endothelial cells. 总被引:6,自引:0,他引:6
W F Cheung D L Straight K J Smith S W Lin H R Roberts D W Stafford 《The Journal of biological chemistry》1991,266(14):8797-8800
To determine the function and specificity in factor IX of the first epidermal growth factor (EGF)-like domain and the eight-amino acid hydrophobic stack encoded by exon C (residues 39-46), these domains were replaced by the corresponding polypeptide regions of factor X and chimeric proteins were produced in human embryo kidney cells. Both chimeras were activated by factor XIa at a rate similar to plasma factor IX and exhibited calcium-dependent fluorescence quenching similar to plasma factor IX. Both chimeras competed equally for binding to the endothelial cell receptor. Our findings make it unlikely that the first EGF-like domain or the hydrophobic stack of factor IX are responsible for the specific binding of factor IX to its endothelial cell receptor. 相似文献