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31.
Nermina Buljubasic K. Martijn Akkerhuis Sanneke P. M. de Boer Jin M. Cheng Hector M. Garcia-Garcia Mattie J. Lenzen Rohit M. Oemrawsingh Linda C. Battes Melissa Rijndertse Evelyn Regar Patrick W. Serruys Robert-Jan van Geuns Eric Boersma Isabella Kardys 《PloS one》2015,10(10)
Background
This study aimed to evaluate the relationship between cigarette smoking and coronary atherosclerotic burden, volume and composition as determined in-vivo by grayscale and virtual histology (VH) intravascular ultrasound (IVUS).Methods and Results
Between 2008 and 2011, (VH-)IVUS of a non-culprit coronary artery was performed in 581 patients undergoing coronary angiography. To account for differences in baseline characteristics, current smokers were matched to never smokers by age, gender and indication for catheterization, resulting in 280 patients available for further analysis. Coronary atherosclerotic plaque volume, burden, composition (fibrous, fibro-fatty, dense calcium and necrotic core) and high-risk lesions (VH-IVUS derived thin-cap fibroatheroma (TCFA), plaque burden ≥70%, minimal luminal area ≤4.0 mm2) were assessed. Cigarette smoking showed a tendency towards higher coronary plaque burden (mean±SD, 38.6±12.5% in current versus 36.4±11.0% in never smokers, p = 0.080; and odds ratio (OR) of current smoking for plaque burden above versus below the median 1.69 (1.04–2.75), p = 0.033). This effect was driven by an association in patients presenting with an acute coronary syndrome (ACS) (current smokers, plaque burden 38.3±12.8% versus never smokers, plaque burden 35.0±11.2%, p = 0.049; OR 1.88 (1.02–3.44), p = 0.042). Fibrous tissue tended to be lower in current smokers (mean±SD, 57.7±10.5% versus 60.4±12.6%, p = 0.050) and fibro-fatty tissue was higher in current smokers (median[IQR], 9.6[6.0–13.7]% versus 8.6[5.8–12.2]%, p = 0.039). However, differences in percentage necrotic core and dense calcium could not be demonstrated. Also, no differences were found with regard to high-risk lesions.Conclusions
An association between smoking and degree of coronary atherosclerosis was present in patients undergoing coronary angiography who presented with ACS. Although smoking was associated with higher fibro-fatty percentage, no associations could be demonstrated with percentage necrotic core, nor with VH-IVUS derived TCFA lesions. Since the magnitude of the differences in both degree and composition of atherosclerosis was modest, clinical relevance of the findings may be questioned. 相似文献32.
33.
Rodrigue Castro Gbedomon Valère Kolawolé Salako Aristide Cossi Adomou Romain Glèlè Kakaï Achille Ephrem Assogbadjo 《Biodiversity and Conservation》2017,26(14):3307-3327
Home gardens have received increasing attention and have been insistently presented as hotspots for agro-biodiversity over the last decades. However, apart from their exceptional high plant species diversity, there is little quantitative evidence of the effectiveness of plant species conservation in home gardens. This study examined this issue by assessing (i) the size and membership of garden flora and the contribution to the maintenance of the national flora, (ii) how home garden flora connects to the larger ecosystem it belongs to and (iii) the conservation status of plant species at the home garden level. 360 home gardens distributed in three agro-ecological zones and nine phyto-geographical districts in Benin were visited and inventoried. Diversity parameters at different taxonomic levels were calculated. Species accumulation and spatial occupancy, multivariate methods and rarity index were also used for data analysis. Findings showed that the 360 studied home gardens hosted up to 14.21% of plant species and 44.32% of plant families of the national flora. Home garden flora was constantly dominated by exotic plant species but strongly connected to their surrounding ecosystems, being composed of at least 60% of plant species from their phyto-geographical districts. Finally, home garden plant species were mostly rare and threatened at the home garden level. In this study, we acknowledge the contribution of home gardens to the maintenance of plant species diversity at regional and global levels than local level. Based on the observed prevalence of exotic species, HG effectiveness in sustainably conserving native plant species biodiversity remains questionable. 相似文献
34.
Emma E. M. Knowles Samuel R. Mathias Josephine Mollon Amanda Rodrigue Marinka M. G. Koenis Thomas D. Dyer Harald H. H. Goring Joanne E. Curran Rene L. Olvera Ravi Duggirala Laura Almasy John Blangero David C. Glahn 《Genes, Brain & Behavior》2019,18(4)
Processing speed is a psychological construct that refers to the speed with which an individual can perform any cognitive operation. Processing speed correlates strongly with general cognitive ability, declines sharply with age and is impaired across a number of neurological and psychiatric disorders. Thus, identifying genes that influence processing speed will likely improve understanding of the genetics of intelligence, biological aging and the etiologies of numerous disorders. Previous genetics studies of processing speed have relied on simple phenotypes (eg, mean reaction time) derived from single tasks. This strategy assumes, erroneously, that processing speed is a unitary construct. In the present study, we aimed to characterize the genetic architecture of processing speed by using a multidimensional model applied to a battery of cognitive tasks. Linkage and QTL‐specific association analyses were performed on the factors from this model. The randomly ascertained sample comprised 1291 Mexican‐American individuals from extended pedigrees. We found that performance on all three distinct processing‐speed factors (Psychomotor Speed; Sequencing and Shifting and Verbal Fluency) were moderately and significantly heritable. We identified a genome‐wide significant quantitative trait locus (QTL) on chromosome 3q23 for Psychomotor Speed (LOD = 4.83). Within this locus, we identified a plausible and interesting candidate gene for Psychomotor Speed (Z = 2.90, P = 1.86 × 10?03). 相似文献
35.
Dongang Nana Rodrigue Roman Ngono Ngane Annie Rosalie Amit Kumar Koanga Mogtomo Martin Luther Vineeta Singh Mouelle Sone Albert 《Parasitology international》2018,67(1):29-33
The gold standard for malaria diagnosis is the microscopic examination of Giemsa stained thick blood smears though microscopy mostly may not detect the presence of Plasmodium species infections in asymptomatic samples. In the reported study, we used two diagnostic methods viz. the conventional microscopic examination and polymerase chain reaction (PCR) assay to analyse the asymptomatic malaria samples. PCR assay amplifying 18S small-subunit ribosomal RNA (SSU rRNA) gene of Plasmodium in 122 samples confirmed 68% of isolates as asymptomatic P. falciparum infections; with 87.9% mono-infections. We observed that the P. malariae positive samples were not diagnosed in microscopic examination of the blood smears but the PCR based diagnostic method revealed the presence of 12% P. malariae infections in asymptomatic samples from Yaoundé region of Cameroon where no official cases of P. malariae have been reported for over a decade. The sequence analysis further confirmed the presence of 12% P. malariae in malaria positive samples with three base pair deletions and five substitutions in the SSU rRNA gene. 相似文献
36.
N. J. Delraso D. R. Mattie C. S. Godin 《In vitro cellular & developmental biology. Plant》1989,25(11):1031-1038
Summary Primary rat hepatocyte suspension cultures (∼2×106 cells) exposed to solubilized 2,3,4-trimethylpentane at concentrations ranging from 7.9 to 31.5 mM under two different culture conditions resulted in a linear dose response, as determined by lactate dehydrogenase leakage
and viability data. A significant increase in the 2,3,4-trimethylpentane effective concentration 50 for primary hepatocytes
occurred when exposures were implemented in medium containing 0.05% albumin. The effective concentration 50 for hepatocytes
exposed to 2,3,4-trimethylpentane in medium lacking and containing albumin were 17.1 and 20.7 mM, respectively. Metabolite analysis by gas chromatography-mass spectrometry of supernatant (lacking or containing albumin)
and cell extracts from hepatocyte cultures exposed to 2,3,4-trimethylpentane for 4 h indicated the presence of three metabolites:
2,3,4-trimethyl-1-pentanol, 2,3,4-trimethyl-2-pentanol, and 2,3,4-trimethyl-1-pentanoic acid. Electron microscopic examination
of 2,3,4-trimethylpentane-exposed primary hepatocytes indicated ultrastructural changes which included abnormal condensed
chromatin association with the nuclear membrane, swollen mitochondria, increased amounts of cytoplasmic lipid, significant
los of microvilli from the cell surface, increased vacuolation, and increased numbers of peroxisomes. Although these changes
were observed under both culture conditions, they were more severe in cultures lacking albumin. This study indicates that
primary hepatocyte suspension cultures provide a useful system for rapidly identifying liver metabolites of selected test
compounds of interest.
Animals used in this study were handled in accordance with the principles stated in the Guide for the Care and Use of Laboratory
Animals, prepared by the Committee on Care and Usage of Laboratory Animals of the Institute of Laboratory Animals Resources,
National Research Council, DHHS, National Institute of Health publication 85–23, 1985, and the Animal Welfare Act of 1966,
as amended. This material has been funded wholly or in part by the United States Air Force under contract F33615-85-C-0532
to NSI Technology Services Corporation. It has been subject to review by the United States Air Force and it has been approved
for publication as a customer document. Mention of trade names or commercial products does not constitute endorsement or recommendation
for use. 相似文献
37.
Lone Jrgensen Nils Brünner Mogens Spang-Thomsen Mattie R. James Robert Clarke Per Dombernowsky Birgit Svenstrup 《The Journal of steroid biochemistry and molecular biology》1997,63(4-6):275-281
Androgen and estrogen metabolism was investigated in the hormone-dependent human breast cancer cell line MCF-7 and its two hormone-resistant sublines MCF-7/LCC1 and MCF-7/LCC2. Using the product isolation method, the activity of aromatase, 5-reductase, 3/β-hydroxysteroid oxidoreductase and 17β-hydroxysteroid oxidoreductase were investigated isolating the following steroids: estriol (E3), estradiol (E2), estrone (E1), 3/β-androstanediol (A-diol), testosterone (T), dihydrotestosterone (DHT), androsterone (AND), androstenedion (4-AD) and androstanedione (A-dion). For all experiments, cells were preincubated with cortisol and subsequently incubated with [14C]T or [14C]4-AD as the substrate in medium without phenol red and with serum charcoal stripped of steroids. The results showed no aromatase activity in any of the cell lines under the experimental conditions used, and preincubation with cortisol had no effect on the enzyme activity. With [14C]T as the substrate, the metabolized level of DHT was very similar in the three cell lines, though MCF-7/LCC1 and MCF-7/LCC2 utilized the substrate to a much lesser extent. The amount of DHT and 4-AD produced were comparable in the two hormone-resistant cell lines, while the amount of 4-AD was significantly higher in MCF-7 cells. No differences in enzyme activity were found in the three cell lines when [14C]4-AD was used as the substrate. This study showed an altered androgen metabolism in the MCF-7/LCC1 and MCF-7/LCC2 sublines compared to the parent MCF-7. However, since treatment with DHT and T inhibited cell growth equally well in all three tumor cell lines, it is unlikely that the found differences in steroid metabolism was involved in the acquisition of the endocrine resistance of the two MCF-7 sublines. 相似文献
38.
39.
Sébastien Rodrigue Rex R. Malmstrom Aaron M. Berlin Bruce W. Birren Matthew R. Henn Sallie W. Chisholm 《PloS one》2009,4(9)