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Preventing horticultural introductions of invasive plants: potential efficacy of voluntary initiatives 总被引:1,自引:0,他引:1
Jennifer W. Burt Adrianna A. Muir Jonah Piovia-Scott Kari E. Veblen Andy L. Chang Judah D. Grossman Heidi W. Weiskel 《Biological invasions》2007,9(8):909-923
Although prevention is the most cost-effective way to avoid the enormous expenses associated with plant invasions, invasive
plants continue to be imported as trade commodities for horticultural use. With very little government regulation of horticultural
imports of invasive plants, efforts have turned toward fostering voluntary initiatives to encourage self-regulation by the
horticulture trade. Our study takes the first step toward evaluating the potential success of these voluntary initiatives.
We conducted a survey of nursery professionals to gauge their perceptions of invasive species, the role of the horticulture
trade in invasive plant introductions, and their participation—potential and actual—in preventive measures outlined in the
St Louis Voluntary Codes of Conduct for nursery professionals. We found nursery professionals to be highly aware of invasive
plants and to accept responsibility as a trade for horticultural introductions. Although only 7% of respondents had heard
of the St Louis Voluntary Codes of Conduct, the majority (57%) reported having participated in at least two of seven preventive
measures, and most (78%) reported willingness to engage in the majority of preventive measures. We found that several factors
significantly predict increased participation in preventive measures, particularly awareness of invasive plants and involvement
in trade associations. We also identified incentives and obstacles to participating in preventive behaviors, including “concern
for the environment” and “lack of information,” respectively. Our results suggest that participation in voluntary initiatives
will improve through increased outreach, and we provide specific recommendations for improving participation in voluntary
programs in the horticulture trade. 相似文献
93.
Skoneczna A McIntyre J Skoneczny M Policinska Z Sledziewska-Gojska E 《Journal of molecular biology》2007,366(4):1074-1086
Saccharomyces cerevisiae Rad30 is the homolog of human DNA polymerase eta whose inactivation leads to the cancer-prone syndrome xeroderma pigmentosum variant. Both human and yeast polymerase eta are responsible for error-free bypass of UV-induced cis-syn pyrimidine dimers and several other DNA lesions. Here we show, using yeast strains expressing TAP-tagged Rad30, that the level of this protein is post-translationally regulated via ubiquitination and proteasome-mediated degradation. The half-life of Rad30 is 20 min and it increases due to proteasomal defects. Mutations inactivating components of the Skp1/cullin/ F-box (SCF) ubiquitin ligase complex: Skp1 and the F-box protein Ufo1 stabilize Rad30. Our results indicate also that ultraviolet irradiation causes transient stabilization of Rad30, which leads, in turn, to temporary accumulation of this polymerase in the cell. We conclude that proteolysis plays an important role in regulating the cellular abundance of Rad30. These results are the first indication of a role for controlled proteasomal degradation in modulating cellular level of translesion DNA polymerase in eukaryotes. 相似文献
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95.
Diatoms are ubiquitous and abundant primary producers that have been traditionally considered as a beneficial food source for grazers and for the transfer of carbon through marine food webs. However, many diatom species produce polyunsaturated aldehydes that disrupt development in the offspring of grazers that feed on these unicellular algae. Here we provide evidence that production of the physiological messenger nitric oxide increases after treatment with the polyunsaturated aldehyde decadienal in embryos of the sea urchin Paracentrotus lividus. At high decadienal concentrations, nitric oxide mediates initial apoptotic events leading to loss of mitochondrial functionality through the generation of peroxynitrite. At low decadienal concentrations, nitric oxide contributes to the activation of hsp70 gene expression thereby protecting embryos against the toxic effects of this aldehyde. When nitric oxide levels were lowered by inhibiting nitric oxide synthase activity, the expression of hsp70 in swimming blastula decreased and the proportion of abnormal plutei increased. However, in later pluteus stages nitric oxide was no longer able to exert this protective function: hsp70 and nitric oxide synthase expression decreased with a consequent increase in the expression of caspase-8. Our findings that nitric oxide production increases rapidly in response to a toxic exogenous stimulus opens new perspectives on the possible role of this gas as an important messenger to environmental stress in sea urchins and for understanding the cellular mechanisms underlying toxicity during diatom blooms. 相似文献
96.
Huffman MD Rao KD Pichon-Riviere A Zhao D Harikrishnan S Ramaiya K Ajay VS Goenka S Calcagno JI Caporale JE Niu S Li Y Liu J Thankappan KR Daivadanam M van Esch J Murphy A Moran AE Gaziano TA Suhrcke M Reddy KS Leeder S Prabhakaran D 《PloS one》2011,6(6):e20821
Objective
To estimate individual and household economic impact of cardiovascular disease (CVD) in selected low- and middle-income countries (LMIC).Background
Empirical evidence on the microeconomic consequences of CVD in LMIC is scarce.Methods and Findings
We surveyed 1,657 recently hospitalized CVD patients (66% male; mean age 55.8 years) from Argentina, China, India, and Tanzania to evaluate the microeconomic and functional/productivity impact of CVD hospitalization. Respondents were stratified into three income groups. Median out-of-pocket expenditures for CVD treatment over 15 month follow-up ranged from 354 international dollars (2007 INT$, Tanzania, low-income) to INT$2,917 (India, high-income). Catastrophic health spending (CHS) was present in >50% of respondents in China, India, and Tanzania. Distress financing (DF) and lost income were more common in low-income respondents. After adjustment, lack of health insurance was associated with CHS in Argentina (OR 4.73 [2.56, 8.76], India (OR 3.93 [2.23, 6.90], and Tanzania (OR 3.68 [1.86, 7.26] with a marginal association in China (OR 2.05 [0.82, 5.11]). These economic effects were accompanied by substantial decreases in individual functional health and productivity.Conclusions
Individuals in selected LMIC bear significant financial burdens following CVD hospitalization, yet with substantial variation across and within countries. Lack of insurance may drive much of the financial stress of CVD in LMIC patients and their families. 相似文献97.
Pawlik P Mostowska A Lianeri M Sajdak S Kędzia H Jagodzinski PP 《Molecular biology reports》2012,39(5):5553-5560
Data indicates that genetic factors alone do not account for ovarian tumorigenesis, suggesting that epigenetic status additionally
affects this process. Therefore, we assessed the possible contribution of polymorphic variants of genes that may affect DNA
methylation to the risk of ovarian cancer incidence in the Polish population. Using PCR-RFLP and HRM analyses, we studied
the distribution of BHMT (rs3733890), MTHFD1 (rs2236225), MTHFR (rs1801133), MTR (rs1805087), MTRR (rs1801394) and TCN2 (rs1801198) genotypes and alleles in patients with ovarian cancer (n = 136) and controls (n = 160). Moreover, using DNA and methylation-specific PCR (MSP) we also determined the methylation of the Cadherin 13
(CDH13) promoter in cancerous tissue from these patients. We did not observe a significant association between all studied gene variants
and the incidence of ovarian cancer. The lowest P
trend = 0.1226 was observed for the MTHFR Ala222Val polymorphism. Moreover, the lowest P = 0.0772 was found in the comparison of MTHFR Ala/Ala versus Val/Val and Val/Ala genotypes in patients and control groups. The multifactor dimensionality reduction analysis
also did not indicate a significant interactive genetic effect on ovarian cancer incidence for all analyzed SNPs. However,
we observed frequent methylation of the CDH13 promoter in approximately 21% (29/136) patients with ovarian carcinomas. Our results might suggest that the selected polymorphic
gene variants may not contribute to ovarian cancer incidence. 相似文献
98.
Mostowska M Lianeri M Oko A Mostowska A Jagodziński PP 《Molecular biology reports》2012,39(5):5933-5941
Various studies have indicated that chemokines such as monocyte chemotactic protein-1 (MCP-1) play an important role in the
pathogenesis of primary glomerulonephritis (GN) and other glomerular diseases. Moreover, patients with primary GN display
aberrant galactosylation of the O-linked carbohydrate moieties of IgA. Therefore, we analysed the distribution of the functional
MCP-1 −2518 A > G (rs 1024611) and 1 beta 1,3-galactosyltransferase (C1GalT1) 1365 A > G (rs1047763) polymorphic variants in patients with primary GN (n = 144) and controls (n = 437) in a sample of the Polish population. We did not find a significant difference in the prevalence of the MCP-1 −2518
A > G and C1GalT1 1365 A > G polymorphisms in patients with primary GN and healthy individuals. Odds Ratio (OR) for GN patients with the MCP-1
−2518 GG genotype was 0.869 (95% CI = 0.410–1.840, P = 0.7130), and OR of the −2518 GG and −2518AG genotypes was 1.004 (95% CI = 0.689–1.464, P = 0.9836). OR for C1GalT1 1365AA genotype was 0.484 (95% CI = 0.181–1.293, P = 0.1402) and OR of the 1365AA and 1365AG genotypes was 0.839 (95% CI = 0.573–1.228, P = 0.3651). We also did not observe a difference in the distribution of alleles between patients and controls. The MCP-1 −2518
G allelic OR was 0.976 (95% CI = 0.725–1.314, P = 0.8744). The OR for the C1GalT1 1365A allele was 0.816 (95% CI = 0.596–1.118, P = 0.205). Moreover, there was no significant association between the MCP-1 −2518 A > G and C1GalT1 1365 A > G genotypes with different morphological types of primary GN or clinical manifestations. Our observations indicate
that the MCP-1 −2518 A > G and C1GalT1 1365 A > G polymorphisms might not be a risk factor in the incidence of primary GN in the Polish population. 相似文献
99.
The link between 20S proteasome activity and post-replication DNA repair in Saccharomyces cerevisiae
We have shown previously that deletion of the Saccharomyces cerevisiae UMP1 gene encoding the 20S proteasome maturase causes sensitivity to UV radiation. In the current report, we have extended this finding to show that mutations specifically compromising chymotrypsin-like or trypsin-like activity of 20S proteasome peptidases also result in increased UV sensitivity. We have also established that mutations affecting proteasome activity, namely ump1Delta, pre2-K108R and pup1-T20A, result in spontaneous and UV-induced mutator phenotypes. To elucidate the origin of these DNA repair phenotypes of the proteasomal mutants, we performed epistasis analysis, with respect to UV sensitivity, using yeast strains with the UMP1 deletion in different DNA repair backgrounds. We show that UMP1 is not epistatic to RAD23 and RAD2, which are involved in the nucleotide excision repair (NER) pathway. Instead, our results indicate that UMP1 as well as PUP1 and PRE2 (encoding catalytic subunits of 20S proteasome) belong to an epistatic group of genes functioning in post-replication DNA repair (PRR) and are hypostatic to RAD18, which, in complex with RAD6, plays a central role in PRR. We also show that UMP1 is epistatic to REV3 and RAD30, although the relationship of UMP1 with these genes is different. 相似文献
100.
The distribution of planktonic copepods in the Adriatic Seahas been analyzed on the basis of 132 samples collected at 35fixed stations during 4 seasonal cruises. A total of 127 specieshave been determined and 3 characteristic copepod communitieshave been identified. The distribution of copepod species hasbeen found to reflect the dual physiognomy of the Adriatic.The shallow northern section is characterized by high densityvalues, low species diversity, and the dominance of speciesbelonging to the estuarine and coastal communities. The relativelydeep waters of the southern section are characterized by lowdensity values, high species diversity, and the presence ofmany species belonging to the upper, middle, and lower zonesof the oceanic community. Temporal variations in the horizontalspread of these 3 communities are discussed in relation to seasonalcycles in abundance, vertical migration patterns, and the currentregime in the Adriatic. 相似文献