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Objectives
Smoking during pregnancy may cause many health problems for pregnant women and their newborns. However, there is a paucity of research that has examined the predictors of smoking during pregnancy in Canada. This study used data from the 2009–2010 Canadian Community Health Survey (CCHS) to estimate the prevalence of smoking during pregnancy and examine the demographic, socioeconomic, health-related and behavioral determinants of this behavior.Methods and Findings
The data were obtained from the 2009–2010 CCHS master data file. Weighted estimates of the prevalence were calculated. Multivariable logistic regression was used to determine demographic, socioeconomic, health related and behavioral characteristics associated with smoking behavior during pregnancy. Women living in the Northern Territories had a high rate of smoking during pregnancy (59.3%). The prevalence of smoking during pregnancy was also high among women under 25 years old, of low socioeconomic status, who reported not having a regular medical doctor, being fair to poor in self-perceived health, having at least one chronic disease, having at least one mental illness, being heavy smokers, and being regular alcohol drinkers. Results from multivariable logistic regression revealed that the odds of smoking during pregnancy were decreased with increasing age (odds ratio [OR], 0.95; 95% confidence interval [CI], 0.91–0.99), having a regular family doctor [OR, 0.24; 95% CI, 0.11–0.52], having highest level of family income [OR, 0.09; 95% CI, 0.03–0.29]. Mothers who reported poor or fair self-perceived health [OR, 2.13; 95% CI, 0.96–4.71] and those who had at least one mental illness [OR, 1.81; 95% CI, 1.00–3.28] had greater odds of smoking during pregnancy.Conclusions
There are a number of demographic, socio-economic, health-related and behavioral characteristics that should be considered in developing and implementing effective population health promotional strategies to prevent smoking during pregnancy, promoting health and well-being of pregnant women and their newborns. 相似文献124.
In order to examine the systematic application of seed-coat microsculpturing in Isatis, seed surfaces of 23 species (41 populations) in four genera of tribe Isatideae were examined using scanning electron microscopy (SEM). Eight types of basic ornamentation patterns were recognized among the studied specimens. Of these, the reticulate–areolate type was the most common and was found in the genera Isatis, Pachypterygium, Samerari and Tauscheria and 15 species (e.g., I. cappodocica, I. kotschyana and I. tinctoria). The reticulate type, the second most frequent, occurred in 7 species while other types each were represented by only one or 2 species. Although different populations of a given species show similar seed-surface sculpturing in most cases, in some polymorphic species like I. cappadocica and I. kotschyana these patterns were variable among populations. To some extent the variation corresponds to infraspecific taxa for some species, but the differences are not significant enough to be useful in the delimitation of the subspecies recognized by previous workers. Moreover, seed-coat characters do not support the separation of genera Isatis, Pachypterygium, Sameraria and Tauscheria. 相似文献
125.
Jason M. Butler Daniel J. Nolan Eva L. Vertes Barbara Varnum-Finney Hideki Kobayashi Andrea T. Hooper Marco Seandel Koji Shido Ian A. White Mariko Kobayashi Larry Witte Chad May Carrie Shawber Yuki Kimura Jan Kitajewski Zev Rosenwaks Irwin D. Bernstein Shahin Rafii 《Cell Stem Cell》2010,6(3):251-264
Highlights? Coculture with endothelial cells promotes HSC expansion and self-renewal ? Endothelial cell effect on HSCs mediated by Notch signaling ? In vivo, sinusoidal endothelial cells (SECs) express Notch ligands ? Blocking vessel remodeling impairs hematopoietic recovery after irradiation 相似文献
126.
In this issue of Cell Stem Cell, Kiel et al. (2007) demonstrate that N-cadherin is not expressed on repopulating hematopoietic stem cells (HSCs) and that reduction of osteoblasts does not affect HSC frequency, suggesting that other molecular pathways may also modulate the interaction of HSCs with their niches. 相似文献
127.
Hany H. Arab Samir A. Salama Ahmed H. Eid Ahmed M. Kabel Nancy N. Shahin 《Journal of cellular physiology》2019,234(12):22424-22438
Excessive drinking of alcohol has been frequently associated with gastric injury; however, its underlying molecular mechanisms have been inadequately investigated. Methyl palmitate (MP) has demonstrated marked hepato-, cardio- and pulmonary protective features; however, its effects on ethanol-induced gastric injury have not been studied. The aim of the present study was to evaluate the potential gastroprotective activity of MP against ethanol-evoked gastric mucosal damage in rats and associated molecular mechanisms, for example, mitogen-activated protein kinases (MAPKs), nuclear factor κB (NF-κB), and phosphoinositide 3 kinase/protein kinase B (PI3K/AKT) pathways. The rat stomachs were examined in terms of the inflammatory, oxidative, and apoptotic perturbations. Current data demonstrated that pretreatment with MP attenuated the gross gastric damage, scores of ulcer index, area of mucosal lesions and histopathology outcomes; actions which were similar to the reference antiulcer omeprazole. MP inhibited NF-κB expression, its nuclear translocation, and the expression of its downstream signals, for example, tumor necrosis factor-α and myeloperoxidase besides restoration of interleukin-10 levels. Western blot analysis revealed that MP counteracted the disruption of MAPKs signaling via lowering p-c-Jun N-terminal kinase 1/2 (p-JNK1/2) expression and restoring the phospho-extracellular signal-regulated kinase 1/2 (p-ERK1/2) levels without affecting p-p38MAPK levels. Additionally, MP improved the antioxidant milieu via diminishing lipid peroxides and enhancing glutathione, glutathione peroxidase, total antioxidant capacity and mucosal nitric oxide. In the context of apoptosis, MP inhibited the cleavage of caspase-3 and poly(ADP-ribose)polymerase (PARP) and Bax protein expression with upregulating B cell lymphoma-2 expression (Bcl-2), thus, promoting gastric cellular survival. This was confirmed by MP activation of the PI3K/AKT pathway manifested by enhanced expression of PI3K p110α and p-AKT. Together, the present findings report the gastroprotective actions of MP mediated via its anti-inflammatory, antioxidant, and antiapoptotic actions. The underlying molecular mechanisms involve, at least partly, the modulation of MAPKs, NF-κB and PI3K/AKT transduction. 相似文献
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129.
Seyed Mohammad Jafari Shahin Zarre Seyed Kazem Alavipanah Farrokh Ghahremaninejad 《Plant Species Biology》2014,29(3):E31-E39
We hypothesized that associations among plant functional traits may differ within different ecological assemblages and plant communities. Association among plant traits including plant maximum height, seed weight, fruit type, pollination mode, mean leaf area, and leaf type were explored within life forms, plant strategy groups along with lowland and montane forest vegetation. In total, 83 sampling plots of 400 m2 were placed along a 2400 m altitudinal gradient in Hyrcanian forest. Importance‐values of species within vegetation types were used for weighting data and trait associations were explored using categorical principal component analysis. A G‐test and Fisher's exact test of independence were used to retest significance of the correlations. Different paired trait associations (association lines) including height–leaf, height–seed, height–pollination, leaf–seed, seed–fruit and fruit–pollination were observed and their ecological or physiological basis was discussed. Life forms, strategy types and vegetation types differed based on association lines. Some of the well‐known trade‐offs appear by increasing scale from ecological groups to vegetation types in Hyrcanian forest. The observed patterns of trait associations in Hyrcanian forest and several other ecosystems of the world call the generality of previously accepted trait correlations into question. 相似文献
130.
Mohammad Hossein Mehraban Salman Odooli Reza Yousefi Rasoul Roghanian Majid Motovali-Bashi Ali-Akbar Moosavi-Movahedi 《Journal of biomolecular structure & dynamics》2017,35(9):1968-1978
A vast research has been conducted to find suitable and safe carriers for vital and pH-sensitive drugs including antibiotics. This article reports the use of easily accessible and abundant purified beta-lactoglobulin (β-LG) protein as the potential carrier of widely used Kanamycin (Kana) and Ciprofloxacin (Cip) antibiotics. Spectroscopic techniques (Fluorescence, UV–vis, Circular Dichroism) combined with molecular docking were used to determine the binding mechanism of these drugs. Fluorescence studies showed moderate binding affinity with the calculated binding constants KCip = 60.1 (±0.2)?×?103 M?1 and Kkana = 2.5 (±0.6)?×?103 M?1 with the order of Cip > Kana. Results of UV–vis were consistent with fluorescence measurements and demonstrated a stronger complexation for Cip rather than Kana. The secondary structure of β-LG was preserved upon interaction with Kana; however, a reduction in β-sheet content from 39.1 to 31.9% was convoyed with an increase in α-helix from 12.8 to 20.5% due to complexation of Cip. Molecular docking studies demonstrated that preferred binding sites of these drugs are not the same and several amino acids are involved in stabilizing the interaction. Based on the achieved results, Kana and Cip can spontaneously bind to β-LG and this protein may serve as their transport vehicle. 相似文献