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11.

Background

Early and exclusive breastfeeding may improve neonatal survival in low resource settings, but suboptimal breastfeeding still exists in areas with high infant mortality. Prelacteal feeding, the practice of giving a non-breastmilk food as a neonate’s first food, has been associated with suboptimal breastfeeding practices. We examined the association of feeding a non-breastmilk food in the first three days of life (early neonatal food, or ENF) with time from birth to initiation of breastfeeding among 25,286 Bangladeshi mother-neonate pairs, in a secondary analysis of a randomized controlled trial in northwestern rural Bangladesh conducted from 2001–2007.

Methods

Trained interviewers assessed the demographic characteristics during pregnancy. At three months postpartum, the interviewers visited participants again and retrospectively assessed demographic and breastfeeding characteristics surrounding the birth. We assessed the relationship between ENF and time to initiation of breastfeeding in hours in both unadjusted and adjusted linear regression analyses. We also calculated reverse cumulative distribution curves for time to initiation of breastfeeding and analyses were stratified by an infant’s ability to breastfeed normally at birth.

Results

The mean?±?SD time from birth to initiation of breastfeeding was 30.6?±?27.9 hours. Only 2,535 (10.0%) of women reported initiating breastfeeding in the first hour after birth and 10,207 (40.4%) reported initiating breastfeeding in the first 12 hours after birth. In adjusted linear regression analyses, feeding ENF was associated with a significant increase in time, in hours, to breastfeeding initiation both among children not able to breastfeed at birth (37.4; 95% CI 33.3, 41.5) and among children able to breastfeed at birth (13.3; 95% CI 12.7, 14.0).

Conclusions

Feeding ENF was strongly associated with delayed initiation of breastfeeding, even after adjusting for other related factors and stratifying on the neonate’s ability to suckle normally after birth. More research is needed to understand the impact of these findings on optimal breastfeeding in this setting. It is possible that ENF feeding and the ability to breastfeed immediately after birth are interrelated in their respective associations to suboptimal breastfeeding initiation. This study in a large population representative of other populations in rural South Asia, demonstrates significantly longer times to breastfeeding initiation than previously appreciated, with a possible important role of ENF feeding.

Trial registration

The randomized controlled trial on which this analysis is based, “Impact of Maternal Vitamin A or Beta-Carotene Supplementation on Maternal and Infant Mortality in Bangladesh”, was registered with ClinicalTrials.gov as trial number ID GHS-A-00-03-00019-00 and identifier NCT00198822. The identifier was first received September 12, 2005 (retrospectively registered). The first participant was enrolled in August 2001.
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12.
Patients with small cell lung cancer (SCLC) die because of chemoresistance. Fibroblast growth factor-2 (FGF-2) increases the expression of antiapoptotic proteins, XIAP and Bcl-X(L), and triggers chemoresistance in SCLC cells. Here we show that these effects are mediated through the formation of a specific multiprotein complex comprising B-Raf, PKCepsilon and S6K2. S6K1, Raf-1 and other PKC isoforms do not form similar complexes. RNAi-mediated downregulation of B-Raf, PKCepsilon or S6K2 abolishes FGF-2-mediated survival. In contrast, overexpression of PKCepsilon increases XIAP and Bcl-X(L) levels and chemoresistance in SCLC cells. In a tetracycline-inducible system, increased S6K2 kinase activity triggers upregulation of XIAP, Bcl-X(L) and prosurvival effects. However, increased S6K1 kinase activity has no such effect. Thus, S6K2 but not S6K1 mediates prosurvival/chemoresistance signalling.  相似文献   
13.
Regenerative medicine is the field concerned with the repair and restoration of the integrity of damaged human tissues as well as whole organs.Since the inception of the field several decades ago,regenerative medicine therapies,namely stem cells,have received significant attention in preclinical studies and clinical trials.Apart from their known potential for differentiation into the various body cells,stem cells enhance the organ's intrinsic regenerative capacity by altering its environment,whether by exogenous injection or introducing their products that modulate endogenous stem cell function and fate for the sake of regeneration.Recently,research in cardiology has highlighted the evidence for the existence of cardiac stem and progenitor cells(CSCs/CPCs).The global burden of cardiovascular diseases’morbidity and mortality has demanded an in-depth understanding of the biology of CSCs/CPCs aiming at improving the outcome for an innovative therapeutic strategy.This review will discuss the nature of each of the CSCs/CPCs,their environment,their interplay with other cells,and their metabolism.In addition,important issues are tackled concerning the potency of CSCs/CPCs in relation to their secretome for mediating the ability to influence other cells.Moreover,the review will throw the light on the clinical trials and the preclinical studies using CSCs/CPCs and combined therapy for cardiac regeneration.Finally,the novel role of nanotechnology in cardiac regeneration will be explored.  相似文献   
14.
Extremophiles - Pigments are an essential part of everyday life on Earth with rapidly growing industrial and biomedical applications. Synthetic pigments account for a major portion of these...  相似文献   
15.
Wang  Weiling  Wang  Xiao  Lv  Zengshuai  Khanzada  Anab  Huang  Mei  Cai  Jian  Zhou  Qin  Huo  Zhongyang  Jiang  Dong 《Journal of Plant Growth Regulation》2022,41(6):2171-2184
Journal of Plant Growth Regulation - This study aims to investigate the effects of cold and salicylic acid (SA) priming on osmolytes accumulation in wheat leaves under freezing stress and its...  相似文献   
16.
A rust fungus was found on the leaves of Euphorbia helioscopia during a field study in Pakistan. Previously, Melampsora euphorbiae, M. euphorbiae-gerardianae and M. helioscopiae have been reported on E. helioscopia, the first two of which are also known from Pakistan. Morphological observations of the newly collected rust samples detected some differences from the previously described Melampsora species on E. helioscopia. The molecular analysis of the ITS and LSU sequences also detected that the rust is different from the previously reported rusts described from E. helioscopia. Based on both morphological comparisons and sequence analysis, the rust is described here as M. pakistanica sp. nov. This species could have potential as a bio-control agent against its host plant—E. helioscopia—which is a weed of wheat fields in Pakistan and elsewhere in the world.  相似文献   
17.
Perovskite solar cells based on CH3NH3PbBr3 with a band gap of 2.3 eV are attracting intense research interests due to their high open‐circuit voltage (Voc) potential, which is specifically relevant for the use in tandem configuration or spectral splitting. Many efforts have been performed to optimize the Voc of CH3NH3PbBr3 solar cells; however, the limiting Voc (namely, radiative Voc:Voc,rad) and the corresponding ΔVoc (the difference between Voc,rad and Voc) mechanism are still unknown. Here, the average Voc of 1.50 V with the maximum value of 1.53 V at room temperature is achieved for a CH3NH3PbBr3 solar cell. External quantum efficiency measurements with electroluminescence spectroscopy determine the Voc,rad of CH3NH3PbBr3 cells with 1.95 V and a ΔVoc of 0.45 V at 295 K. When the temperature declines from 295 to 200 K, the obtained Voc remains comparably stable in the vicinity of 1.5 V while the corresponding ΔVoc values show a more significant increase. Our findings suggest that the Voc of CH3NH3PbBr3 cells is primarily limited by the interface losses induced by the charge extraction layer rather than by bulk dominated recombination losses. These findings are important for developing strategies how to further enhance the Voc of CH3NH3PbBr3‐based solar cells.  相似文献   
18.
Metagenomic approach permits us to obtain the latent resources from culturable and unculturable microorganisms in ecosystem. In this study, high-throughput sequencing was practiced to comprehensively probe prokaryotic community within extreme acidic environment of Baiyin open-pit mine stope, which varied in pH and other physicochemical parameters. Bioinformatics analysis was further accomplished to process millions of Illumina reads and analyzed alpha and beta diversities, and prokaryotic community profile in different samples obtained from the acidic mine stope. Diversity indices such as ACE, Chao, Shannon, and Simpson were varied among samples. Both taxon richness and evenness were significantly higher in the solid samples than that of the water samples. Taxonomic diversity was unexpectedly higher within confined pit ecosystem. Most of the sequences were assigned to phyla Proteobacteria, Firmicutes, and Acidobacteria. In archaea, Euryarchaeota and Thaumarchaeota were major phyla reported, however, archaea occupied very little share in the metagenome. At class level, variation in community structure was higher within samples. Among iron- and sulfur-related acidophiles, 30.8% of the sequences were unidentified at genera level, while the remaining were dominated by sulfur and/or iron oxidizing Acidithiobacillus and heterotrophic Acidiphilum related groups. The community profile of solid and water groups was different and metagenomic biomarkers were higher in solid, while acidophiles and archaea were reported only in water group by using LEfSe. Among samples, community structure and abundance was varied in terms of OTUs abundance, which clearly indicates spatial variation and proposed the influence of physicochemical and geochemical properties on phylogenetic diversity. This study offers numerous treasured datasets for better understanding the community composition under the influence of geochemical and physicochemical factors and possible novelty in terms of taxonomic/phylogenetic diversity in acidic ecosystem.  相似文献   
19.
Aqucous leaf extract of common lambsquarters (Chenopodium album L.) was evaluated alone or in combination with NaCl for its effect on germination and rice seedling growth. The treatments have no effect on germination. However, growth of both shoot and root significantly decreased under NaCl alone and in combination with leaf extract. Root growth was affected more than the shoot and the effect of NaCl was accentuated in the presence of leaf extract.  相似文献   
20.
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