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181.
Thomas C Nightingale CM Donin AS Rudnicka AR Owen CG Sattar N Cook DG Whincup PH 《PloS one》2012,7(3):e32619
Background
Socio-economic position (SEP) and ethnicity influence type 2 diabetes mellitus (T2DM) risk in adults. However, the influence of SEP on emerging T2DM risks in different ethnic groups and the contribution of SEP to ethnic differences in T2DM risk in young people have been little studied. We examined the relationships between SEP and T2DM risk factors in UK children of South Asian, black African-Caribbean and white European origin, using the official UK National Statistics Socio-economic Classification (NS-SEC) and assessed the extent to which NS-SEC explained ethnic differences in T2DM risk factors.Methods and Findings
Cross-sectional school-based study of 4,804 UK children aged 9–10 years, including anthropometry and fasting blood analytes (response rates 70%, 68% and 58% for schools, individuals and blood measurements). Assessment of SEP was based on parental occupation defined using NS-SEC and ethnicity on parental self-report. Associations between NS-SEC and adiposity, insulin resistance (IR) and triglyceride differed between ethnic groups. In white Europeans, lower NS-SEC status was related to higher ponderal index (PI), fat mass index, IR and triglyceride (increases per NS-SEC decrement [95%CI] were 1.71% [0.75, 2.68], 4.32% [1.24, 7.48], 5.69% [2.01, 9.51] and 3.17% [0.96, 5.42], respectively). In black African-Caribbeans, lower NS-SEC was associated with lower PI (−1.12%; [−2.01, −0.21]), IR and triglyceride, while in South Asians there were no consistent associations between NS-SEC and T2DM risk factors. Adjustment for NS-SEC did not appear to explain ethnic differences in T2DM risk factors, which were particularly marked in high NS-SEC groups.Conclusions
SEP is associated with T2DM risk factors in children but patterns of association differ by ethnic groups. Consequently, ethnic differences (which tend to be largest in affluent socio-economic groups) are not explained by NS-SEC. This suggests that strategies aimed at reducing social inequalities in T2DM risk are unlikely to reduce emerging ethnic differences in T2DM risk. 相似文献182.
183.
Ewa Jankowska-Steifer Gayane Martirosian Alicja Ekiel Aldona Komar Barbara Wiechuła Jarosław Jóźwiak Paweł Cieślik Stanisław Moskalewski 《World journal of microbiology & biotechnology》2011,27(7):1689-1694
We have previously demonstrated that C. histolyticum reference strain ATCC 19401 produces not only lethal factor but also hitherto unrecognized vacuolating toxin. The aim of
this study was to compare vacuolating and lethal activities of six reference C. histolyticum strains (ATCC 6282, 8034, 17859, 17860, 19401 and 25770) and to determine whether production of vacuolating toxin is strain-dependent
and how the amounts of both toxins produced by the same strain are related to each other and also to protease, collagenase
and clostripain activities. All strains produced vacuolating and lethal toxins as well as collagenase, clostripain and proteases,
but with different yield. Strain ATCC 19401 demonstrated considerable vacuolating and lethal activities and low activity of
collagenase, clostripain and proteases. In other strains such relationship was not evident. Positive correlations were observed
in collagenase and clostripain activities of all studied C. histolyticum strains (r = 0.71). Positive correlations were detected also in vacuolating activities of studied strains and clostripain (r = 0.62) and collagenase (r = 0.87) production, and this effect was statistically significant (P < 0.05). Negative non-significant correlations were detected: (a) in lethal activities of studied strains and clostripain,
or collagenase activities, (b) in vacuolating activities and protease production. 相似文献
184.
Sylwia Bloch Bożena Nejman-Faleńczyk Karolina Pierzynowska Ewa Piotrowska Alicja Węgrzyn Christelle Marminon 《Journal of enzyme inhibition and medicinal chemistry》2018,33(1):639-650
Oxidative stress may be the major cause of induction of Shiga toxin-converting (Stx) prophages from chromosomes of Shiga toxin-producing Escherichia coli (STEC) in human intestine. Thus, we aimed to test a series of novel antioxidant compounds for their activities against prophage induction, thus, preventing pathogenicity of STEC. Forty-six compounds (derivatives of carbazole, indazole, triazole, quinolone, ninhydrine, and indenoindole) were tested. Fifteen of them gave promising results and were further characterized. Eleven compounds had acceptable profiles in cytotoxicity tests with human HEK-293 and HDFa cell lines. Three of them (selected for molecular studies) prevent the prophage induction at the level of expression of specific phage genes. In bacterial cells treated with hydrogen peroxide, expression of genes involved in the oxidative stress response was significantly less efficient in the presence of the tested compounds. Therefore, they apparently reduce the oxidative stress, which prevents induction of Stx prophage in E. coli. 相似文献
185.
186.
The Clp ATPases define a novel class of molecular chaperones 总被引:14,自引:3,他引:11
The Clp ATPases were originally identified as a regulatory component of the bacterial ATP-dependent Clp serine proteases. Proteins homologous to the Escherichia coli Clp ATPases (ClpA, B, X or Y) have been identified in every organism examined so far. Recent data suggest that the Clp ATPases are not only specificity factors which help to 'present' various protein substrates to the ClpP or other catalytic proteases, but are also molecular chaperones which can function independently of ClpP. This review discusses the recent evidence that the Clp ATPases are indeed molecular chaperones capable of either repairing proteins damaged during stress conditions or activating the initiation proteins for Mu, λ or P1 DNA replication. A mechanism is suggested to explain how the Clp ATPases 'decide' whether to repair or destroy their protein substrates. 相似文献
187.
Ewa Witkowska Alicja Oriowska Jan Izdebski Jan Salwa Joanna Wietrzyk Adam Opolski 《Journal of peptide science》2004,10(5):285-290
Eleven analogues of the laminin pentapeptide amide fragment Tyr-Ile-Gly-Ser-Arg-NH2 (YIGSR-NH2) corresponding to a B1 chain fragment of the glycoprotein laminin have been synthesized by the solid phase method, and their biological activity has been studied in vitro by a cell adhesion assay: all of them inhibited the adhesion of LLC tumor cells to laminin. The analogues were found to be more resistant to enzymatic degradation in human serum than YIGSR-NH2 itself. Analogue DatIGSHar-NH2 was selected for an experimental pulmonary metastasis assay in vivo: it had higher antimetastatic activity than YIGSR-NH2. 相似文献
188.
Iwona Skrzecz Robert Wolski Alicja Sowinska Jerzy Raczko Wojciech Janiszewski Robert Kuzminski 《Journal of Applied Entomology》2019,143(4):397-407
This study aimed to develop a semiochemical‐baited trapping system to monitor the populations of small banded pine weevil, Pissodes castaneus, a serious pest in Pinus sylvestris young stands that are weakened by biotic and abiotic factors. The scope of the work included the development of a dispenser for compounds (ethanol and α‐pinene) emitted by P. sylvestris and the pheromones of P. castaneus: grandisol and grandisal. Additionally, the effectiveness of beetle catches in different types of traps (unitrap, cross‐unitrap and long and short pipe traps) baited with a dispenser was assessed. The olfactometric studies showed that most of the newly hatched beetles that had not fed were attracted by a mixture of grandisol and grandisal. However, in the group of feeding beetles, half were attracted by a mixture of ethanol and α‐pinene. These results indicated that both pheromones and α‐pinene plus ethanol should be useful for capturing P. castaneus beetles. In the field trials, the highest efficiency was found in baited unitraps that caught up to several hundred P. castaneus beetles, while the baited cross‐unitraps caught up to a few dozen beetles. No insects were found in either type of baited pipe trap or in any of the unbaited control traps. The baited unitraps and cross‐unitraps also collected, with varied intensity, Hylobius abietis beetles, a serious pest of reforestations. These results indicate the possibility of using a unitrap baited with a 4‐component attractant for monitoring P. castaneus in integrated pest management for the protection of young forests. 相似文献
189.
The antioxidative action of amphiphilic mono-(alkanoylamino) ethyldimethylamine-N-oxides (EDA), di-N-oxides 1,1-bis {[2-(N,N-dimethylamino)ethyl]amido}alkane-di-N-oxides (MEDA) and 1,1-bis {[3-(N,N-dimethylamino)propyl]amido}alkane-di-N-oxides (MPDA) with a 12- and 14-membered acyl chain against tert-butylhydroperoxide (TBHP)-produced peroxyl and paraquat (PQ)-generated superoxide radicals was determined in superoxide dismutase-deficient mutants of Saccharomyces cerevisiae, and, in parallel, in a chemical assay based on chemiluminescence changes caused in a luminol system by peroxyl radicals generated from the azo-compound 2,2'-azobis(2-amidinopropane dihydrochloride) (AAPH). At 30 micromol/L, the shorter-chain compounds did not affect strain survival while longer-chain ones, in some cases, lowered the survival of sod2 and sod1 sod2 cells. Whether nontoxic or medium-toxic, all N-oxides protected the sod strains against the toxic effect of PQ and TBHP, the protection being stronger with the di-N-oxides. The survival was lowered only by 14-MPDA in the TBHP-exposed sod2 mutant. Membrane lipids isolated from all strains were protected against TBHP-induced peroxidation by both mono- and di-N-oxides, the protection being dependent on the alkyl chain length. Mono-N-oxides were again less active than di-N-oxides with the same alkyl chains, the antiperoxidative activity being also dependent on lipids isolated from the individual mutants. In the chemiluminescence assay, the IC50 value of the N-oxides for scavenging of radicals generated from AAPH generally decreased (i.e. the scavenging efficiency increased) with increasing chain length and was the highest in MEDA. 相似文献
190.