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181.
From the leaves of Ageratina cylindrica, in addition to the described [(2S)‐2‐{4‐formyl‐5‐hydroxy‐2‐[(2‐methylpropanoyl)oxy]phenyl}oxiran‐2‐yl]methyl benzoate (cylindrinol A, 8 ), seven new thymol derivatives were isolated and named cylindrinols B – H ( 1 – 7 ). The structures of these compounds were established as (2‐{4‐(hydroxymethyl)‐2‐[(2‐methylpropanoyl)oxy]phenyl}oxiran‐2‐yl)methyl benzoate ( 1 ), (2‐{4‐formyl‐2‐[(2‐methylpropanoyl)oxy]phenyl}oxiran‐2‐yl)methyl benzoate ( 2 ), (2‐{4‐[(acetyloxy)methyl]‐2‐[(2‐methylpropanoyl)oxy]phenyl}oxiran‐2‐yl)methyl benzoate ( 3 ), [2‐(2‐[(2‐methylpropanoyl)oxy]‐4‐{[(2‐methylpropanoyl)oxy]methyl}phenyl)oxiran‐2‐yl]methyl benzoate ( 4 ), [2‐(5‐hydroxy‐2‐[(2‐methylpropanoyl)oxy]‐4‐{[(2‐methylpropanoyl)oxy]methyl}phenyl)oxiran‐2‐yl]methyl benzoate ( 5 ), 2‐{4‐(hydroxymethyl)‐2‐[(2‐methylpropanoyl)oxy]phenyl}prop‐2‐en‐1‐yl benzoate ( 6 ), and 2‐hydroxy‐2‐[2‐hydroxy‐4‐(hydroxymethyl)‐phenyl]‐3‐[(2‐methylpropanoyl)oxy]propyl benzoate ( 7 ), by spectroscopic means. Compounds 1 showed moderate antiprotozoal activity on both protozoa. Compounds 4 and 5 showed selectivity on Giardia lamblia trophozoites. All isolated compounds were less active than two antiprotozoal drugs, metronidazole and emetine, used as positive controls. Compound 5 exhibited a high inhibitory effect on hyperpropulsive movement of the small intestine in rats; its effect was best than loperamide, antidiarrheal drug used as a positive control.  相似文献   
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183.
IntroductionThe aim of the study was to analyse genetic architecture of RA by utilizing multiparametric statistical methods such as linear discriminant analysis (LDA) and redundancy analysis (RDA).MethodsA total of 1393 volunteers, 499 patients with RA and 894 healthy controls were included in the study. The presence of shared epitope (SE) in HLA-DRB1 and 11 SNPs (PTPN22 C/T (rs2476601), STAT4 G/T (rs7574865), CTLA4 A/G (rs3087243), TRAF1/C5 A/G (rs3761847), IRF5 T/C (rs10488631), TNFAIP3 C/T (rs5029937), AFF3 A/T (rs11676922), PADI4 C/T (rs2240340), CD28 T/C (rs1980422), CSK G/A (rs34933034) and FCGR3A A/C (rs396991), rheumatoid factor (RF), anti–citrullinated protein antibodies (ACPA) and clinical status was analysed using the LDA and RDA.ResultsHLA-DRB1, PTPN22, STAT4, IRF5 and PADI4 significantly discriminated between RA patients and healthy controls in LDA. The correlation between RA diagnosis and the explanatory variables in the model was 0.328 (Trace = 0.107; F = 13.715; P = 0.0002). The risk variants of IRF5 and CD28 genes were found to be common determinants for seropositivity in RDA, while positivity of RF alone was associated with the CTLA4 risk variant in heterozygous form. The correlation between serologic status and genetic determinants on the 1st ordinal axis was 0.468, and 0.145 on the 2nd one (Trace = 0.179; F = 6.135; P = 0.001). The risk alleles in AFF3 gene together with the presence of ACPA were associated with higher clinical severity of RA.ConclusionsThe association among multiple risk variants related to T cell receptor signalling with seropositivity may play an important role in distinct clinical phenotypes of RA. Our study demonstrates that multiparametric analyses represent a powerful tool for investigation of mutual relationships of potential risk factors in complex diseases such as RA.  相似文献   
184.
Barrier islands on the north coast of the Gulf of Mexico are an internationally important coastal resource. Each spring hundreds of thousands of Nearctic-Neotropical songbirds crossing the Gulf of Mexico during spring migration use these islands because they provide the first landfall for individuals following a trans-Gulf migratory route. The effects of climate change, particularly sea level rise, may negatively impact habitat availability for migrants on barrier islands. Our objectives were (1) to confirm the use of St. George Island, Florida by trans-Gulf migrants and (2) to determine whether forested stopover habitat will be available for migrants on St. George Island following sea level rise. We used avian transect data, geographic information systems, remote sensing, and simulation modelling to investigate the potential effects of three different sea level rise scenarios (0.28 m, 0.82 m, and 2 m) on habitat availability for trans-Gulf migrants. We found considerable use of the island by spring trans-Gulf migrants. Migrants were most abundant in areas with low elevation, high canopy height, and high coverage of forests and scrub/shrub. A substantial percentage of forest (44%) will be lost by 2100 assuming moderate sea level rise (0.82 m). Thus, as sea level rise progresses, less forests will be available for migrants during stopover. Many migratory bird species’ populations are declining, and degradation of barrier island stopover habitat may further increase the cost of migration for many individuals. To preserve this coastal resource, conservation and wise management of migratory stopover areas, especially near ecological barriers like the Gulf of Mexico, will be essential as sea levels rise.  相似文献   
185.
B-cell chronic lymphocytic leukemia (CLL) remains an incurable disease, and despite the improvement achieved by therapeutic regimes developed over the last years still a subset of patients face a rather poor prognosis and will eventually relapse and become refractory to therapy. The natural rotenoid deguelin has been shown to induce apoptosis in several cancer cells and cell lines, including primary human CLL cells, and to act as a chemopreventive agent in animal models of induced carcinogenesis. In this work, we show that deguelin induces apoptosis in vitro in primary human CLL cells and in CLL-like cells from the New Zealand Black (NZB) mouse strain. In both of them, deguelin dowregulates AKT, NFκB and several downstream antiapoptotic proteins (XIAP, cIAP, BCL2, BCL-XL and survivin), activating the mitochondrial pathway of apoptosis. Moreover, deguelin inhibits stromal cell-mediated c-Myc upregulation and resistance to fludarabine, increasing fludarabine induced DNA damage. We further show that deguelin has activity in vivo against NZB CLL-like cells in an experimental model of CLL in young NZB mice transplanted with spleen cells from aged NZB mice with lymphoproliferation. Moreover, the combination of deguelin and fludarabine in this model prolonged the survival of transplanted mice at doses of both compounds that were ineffective when administered individually. These results suggest deguelin could have potential for the treatment of human CLL.  相似文献   
186.

Objective

To establish reference charts for fetal cerebellar vermis height in an unselected population.

Methods

A prospective cross-sectional study between September 2009 and December 2014 was carried out at ALTAMEDICA Fetal–Maternal Medical Centre, Rome, Italy. Of 25203 fetal biometric measurements, 12167 (48%) measurements of the cerebellar vermis were available. After excluding 1562 (12.8%) measurements, a total of 10605 (87.2%) fetuses were considered and analyzed once only. Parametric and nonparametric quantile regression models were used for the statistical analysis. In order to evaluate the robustness of the proposed reference charts regarding various distributional assumptions on the ultrasound measurements at hand, we compared the gestational age-specific reference curves we produced through the statistical methods used. Normal mean height based on parametric and nonparametric methods were defined for each week of gestation and the regression equation expressing the height of the cerebellar vermis as a function of gestational age was calculated. Finally the correlation between dimension/gestation was measured.

Results

The mean height of the cerebellar vermis was 12.7mm (SD, 1.6mm; 95% confidence interval, 12.7–12.8mm). The regression equation expressing the height of the CV as a function of the gestational age was: height (mm) = -4.85+0.78 x gestational age. The correlation between dimension/gestation was expressed by the coefficient r = 0.87.

Conclusion

This is the first prospective cross-sectional study on fetal cerebellar vermis biometry with such a large sample size reported in literature. It is a detailed statistical survey and contains new centile-based reference charts for fetal height of cerebellar vermis measurements.  相似文献   
187.
In Mycobacterium tuberculosis (MTB) infection, the complex interaction of host immune system and the mycobacteria is associated with levels of cytokines production that play a major role in determining the outcome of the disease. Several single-nucleotide polymorphisms (SNPs) in cytokine genes have been associated with tuberculosis (TB) outcome. The aim of this study was to evaluate the association between previously reported SNPs IL2–330 T>G (rs2069762); IL4–590 C>T (rs2243250); IL6–174 G>C (rs1800795); IL10–592 A>C (rs1800872); IL10–1082 G>A (rs1800896); IL17A -692 C>T (rs8193036); IL17A -197 G>A (rs2275913); TNF -238 G>A (rs361525); TNF -308 G>A (rs1800629) and IFNG +874 T>A (rs2430561) and pulmonary TB (PTB) susceptibility. We conducted a case-control study in individuals from Southern Brazil who were recruited between February 2012 and October 2013 in a high incidence TB city. We performed a multiplex genotyping assay in 191 patients with PTB and 175 healthy subjects. Our results suggest a decreased risk for PTB development associated with the IL17A -197A allele (OR = 0.29; p = 0.04), AA genotype (OR = 0.12; p = 0.04) and A carrier (AG/AA) (OR = 0.29; p = 0.004) and IL6 -174C carrier (CC/CG) (OR = 0.46; p = 0.04). We could not properly analyze IL17A -692 C>T (rs8193036) and IFNG +874T>A due to genotypic inconsistencies and found no evidence of association for the IL2, IL4, IL10 and TNF polymorphisms and PTB. In conclusion, our results show a protective effect of IL17 and IL6 polymorphisms on PTB outcome in Southern Brazilian population.  相似文献   
188.
The interaction of chemicals with DNA may lead to genotoxicity, mutation or carcinogenicity. A simple open tubular capillary electrochromatographic method is proposed to rapidly assess the interaction affinity of three environmental contaminants (1,4-phenylenediamine, pyridine and 2,4-diaminotoluene) to DNA by measuring their retention in the capillaries coated with DNA probes. DNA oligonucleotide probes were immobilized on the inner wall of a fused silica capillary that was first derivatized with 3-(aminopropyl)-triethoxysilane (APTES). The difference in retention times and factors was considered as the difference in interaction affinity of the contaminants to the DNA probes. The interaction of the contaminants with both double-stranded (dsDNA) and single-stranded DNA (ssDNA) coatings was compared. Retention factors of 1,4-phenylenediamine, pyridine and 2,4-diaminotoluene in the capillary coated with ssDNA probe were 0.29, 0.42, and 0.44, respectively. A similar trend was observed in the capillary coated with dsDNA, indicating that 2,4-diaminotoluene has the highest affinity among the three contaminants. The relative standard deviation (RSD) for the retention factors was in the range of 0.05–0.69% (n = 3). The results demonstrated that the developed technique could be applied for preliminary screening purpose to provide DNA interaction affinity information of various environmental contaminants.  相似文献   
189.
Disposable orbitally shaken TubeSpin bioreactor 600 tubes (TS600s) were recently developed for the bench-scale cultivation of animal cells in suspension. Here we compared batch cultures of Sf9 insect cells in TS600s, spinner flasks, and shake flasks. Superior cell growth was observed in TS600s and shake flasks as compared with spinner flasks, and more favorable oxygen-enriched cell culture conditions were observed in TS600s as compared with either spinner or shake flasks. The results demonstrated the suitability of TS600s as a disposable vessel for the cultivation of Sf9 cells in suspension.  相似文献   
190.
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