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21.
BackgroundIt is estimated that over 250 million children under 5 years of age in low- and middle-income countries (LMICs) do not reach their full developmental potential. Poor maternal diet, anemia, and micronutrient deficiencies during pregnancy are associated with suboptimal neurodevelopmental outcomes in children. However, the effect of prenatal macronutrient and micronutrient supplementation on child development in LMIC settings remains unclear due to limited evidence from randomized trials.Methods and findingsWe conducted a 3-arm cluster-randomized trial (n = 53 clusters) that evaluated the efficacy of (1) prenatal multiple micronutrient supplementation (MMS; n = 18 clusters) and (2) lipid-based nutrient supplementation (LNS; n = 18 clusters) as compared to (3) routine iron–folic acid (IFA) supplementation (n = 17 clusters) among pregnant women in the rural district of Madarounfa, Niger, from March 2015 to August 2019 (ClinicalTrials.gov identifier NCT02145000). Children were followed until 2 years of age, and the Bayley Scales of Infant and Toddler Development III (BSID-III) were administered to children every 3 months from 6 to 24 months of age. Maternal report of WHO gross motor milestone achievement was assessed monthly from 3 to 24 months of age. An intention-to-treat analysis was followed. Child BSID-III data were available for 559, 492, and 581 singleton children in the MMS, LNS, and IFA groups, respectively. Child WHO motor milestone data were available for 691, 781, and 753 singleton children in the MMS, LNS, and IFA groups, respectively. Prenatal MMS had no effect on child BSID-III cognitive (standardized mean difference [SMD]: 0.21; 95% CI: −0.20, 0.62; p = 0.32), language (SMD: 0.16; 95% CI: −0.30, 0.61; p = 0.50) or motor scores (SMD: 0.18; 95% CI: −0.39, 0.74; p = 0.54) or on time to achievement of the WHO gross motor milestones as compared to IFA. Prenatal LNS had no effect on child BSID-III cognitive (SMD: 0.17; 95% CI: −0.15, 0.49; p = 0.29), language (SMD: 0.11; 95% CI: −0.22, 0.44; p = 0.53) or motor scores (SMD: −0.04; 95% CI: −0.46, 0.37; p = 0.85) at the 24-month endline visit as compared to IFA. However, the trajectory of BSID-III cognitive scores during the first 2 years of life differed between the groups with children in the LNS group having higher cognitive scores at 18 and 21 months (approximately 0.35 SD) as compared to the IFA group (p-value for difference in trajectory <0.001). Children whose mothers received LNS also had earlier achievement of sitting alone (hazard ratio [HR]: 1.57; 95% CI: 1.10 to 2.24; p = 0.01) and walking alone (1.52; 95% CI: 1.14 to 2.03; p = 0.004) as compared to IFA, but there was no effect on time to achievement of other motor milestones. A limitation of our study is that we assessed child development up to 2 years of age, and, therefore, we may have not captured effects that are easier to detect or emerge at older ages.ConclusionsThere was no benefit of prenatal MMS on child development outcomes up to 2 years of age as compared to IFA. There was evidence of an apparent positive effect of prenatal LNS on cognitive development trajectory and time to achievement of selected gross motor milestones.Trial registrationClinicalTrials.gov NCT02145000.

Christopher R. Sudfeld and colleagues evaluate the benefit of multiple micronutrient supplementation and medium‐quantity lipid‐based nutrient supplementation in pregnancy on child development in rural Niger.  相似文献   
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Background

Diet-related noncommunicable diseases (NCDs) are increasing rapidly in low- and middle-income countries (LMICs) and constitute a leading cause of mortality. Although a call for global action has been resonating for years, the progress in national policy development in LMICs has not been assessed. This review of strategies to prevent NCDs in LMICs provides a benchmark against which policy response can be tracked over time.

Methods and Findings

We reviewed how government policies in LMICs outline actions that address salt consumption, fat consumption, fruit and vegetable intake, or physical activity. A structured content analysis of national nutrition, NCDs, and health policies published between 1 January 2004 and 1 January 2013 by 140 LMIC members of the World Health Organization (WHO) was carried out. We assessed availability of policies in 83% (116/140) of the countries. NCD strategies were found in 47% (54/116) of LMICs reviewed, but only a minority proposed actions to promote healthier diets and physical activity. The coverage of policies that specifically targeted at least one of the risk factors reviewed was lower in Africa, Europe, the Americas, and the Eastern Mediterranean compared to the other two World Health Organization regions, South-East Asia and Western Pacific. Of the countries reviewed, only 12% (14/116) proposed a policy that addressed all four risk factors, and 25% (29/116) addressed only one of the risk factors reviewed. Strategies targeting the private sector were less frequently encountered than strategies targeting the general public or policy makers.

Conclusions

This review indicates the disconnection between the burden of NCDs and national policy responses in LMICs. Policy makers urgently need to develop comprehensive and multi-stakeholder policies to improve dietary quality and physical activity. Please see later in the article for the Editors'' Summary  相似文献   
25.
Melissopalynological analysis of 60 honey samples collected from 50 Kenyan Top Bar Hives in the North Sudanian phytogeographical region of Burkina Faso established the plant species foraged by honeybees Apis mellifera adansonii. Forty-three pollen types from 29 families were identified in the honey samples. The most common families were Mimosaceae (9.30%), Asteraceae (6.98%) and Anacardiaceae (6.98%). The most frequently visited plants were Combretum (66.66%), Tridax procumbens (66.66), Acacia seyal-group (50%), Cleome viscosa-group (50%) and Cyperus esculentus (41.67%). The results showed that Apis mellifera adansonii is polylectic with a heterogeneous foraging behaviour. Pollen analysis showed that the honeys from the two main honey flows of Burkina Faso were polyfloral.  相似文献   
26.

Background

Apical membrane antigen 1 (AMA1) is one of the best-studied blood-stage malaria vaccine candidates. When an AMA1 vaccine was tested in a malaria naïve population, it induced functionally active antibodies judged by Growth Inhibition Assay (GIA). However, the same vaccine failed to induce higher growth-inhibitory activity in adults living in a malaria endemic area. Vaccination did induce functionally active antibodies in malaria-exposed children with less than 20% inhibition in GIA at baseline, but not in children with more than that level of baseline inhibition.

Methods

Total IgGs were purified from plasmas collected from the pediatric trial before and after immunization and pools of total IgGs were made. Another set of total IgGs was purified from U.S. adults immunized with AMA1 (US-total IgG). From these total IgGs, AMA1-specific and non-AMA1 IgGs were affinity purified and the functional activity of these IgGs was evaluated by GIA. Competition ELISA was performed with the U.S.-total IgG and non-AMA1 IgGs from malaria-exposed children.

Results

AMA1-specific IgGs from malaria-exposed children and U.S. vaccinees showed similar growth-inhibitory activity at the same concentrations. When mixed with U.S.-total IgG, non-AMA1 IgGs from children showed an interference effect in GIA. Interestingly, the interference effect was higher with non-AMA1 IgGs from higher titer pools. The non-AMA1 IgGs did not compete with anti-AMA1 antibody in U.S.-total IgG in the competition ELISA.

Conclusion

Children living in a malaria endemic area have a fraction of IgGs that interferes with the biological activity of anti-AMA1 antibody as judged by GIA. While the mechanism of interference is not resolved in this study, these results suggest it is not caused by direct competition between non-AMA1 IgG and AMA1 protein. This study indicates that anti-malaria IgGs induced by natural exposure may interfere with the biological effect of antibody induced by an AMA1-based vaccine in the target population.  相似文献   
27.
Chronic inflammation is a hallmark of pulmonary diseases, which leads to lung parenchyma destruction (emphysema) and obstructive bronchiolitis occurring in both chronic obstructive pulmonary disease and asthma. Inflammation is strongly correlated with low intracellular cAMP levels and increase in specific cAMP hydrolyzing activity. The aim of the present study was to investigate the role of the cyclic phosphodiesterase type 4 (PDE4) in human lung and to determine the effects of NCS 613, a new PDE4 inhibitor, on lung inflammation and bronchial hyperresponsiveness. High cAMP-PDE activities were found in the cytosoluble fractions from human lung parenchyma and distal bronchi. PDE4 (rolipram sensitive) represented 40% and 56% of total cAMP-PDE activities in the above-corresponding tissues. Moreover, PDE4A, PDE4B, PDE4C, and PDE4D isoforms were detected in all three subcellular fractions (cytosolic, microsomal, and nuclear) with differential distributions according to specific variants. Pharmacological treatments with NCS 613 significantly decreased PDE4 activity and reduced IκBα degradation in cultured parenchyma, both of which are usually correlated with a lower inflammation status. Moreover, NCS 613 pretreatment potentiated isoproterenol-induced relaxations in human distal bronchi, while reducing TNF-α-induced hyperresponsiveness in cultured bronchi, as assessed in the presence of methacholine, U-46619, or histamine. This reducing effect of NCS 613 on human bronchi hyperresponsiveness triggered by TNF-α was related to a lower expression level of PDE4B and PDE4C, as well as a downregulation of the phosphorylated forms of p38-MAPK, CPI-17, and MYPT-1, which are known to control tone. In conclusion, specific PDE4 inhibitors, such as NCS 613, may represent an alternative and isoform-specific approach toward reducing human lung inflammation and airway overreactivity.  相似文献   
28.
Our understanding of the composition of multi-clonal malarial infections and the epidemiological factors which shape their diversity remain poorly understood. Traditionally within-host diversity has been defined in terms of the multiplicity of infection (MOI) derived by PCR-based genotyping. Massively parallel, single molecule sequencing technologies now enable individual read counts to be derived on genome-wide datasets facilitating the development of new statistical approaches to describe within-host diversity. In this class of measures the FWS metric characterizes within-host diversity and its relationship to population level diversity. Utilizing P. falciparum field isolates from patients in West Africa we here explore the relationship between the traditional MOI and FWS approaches. FWS statistics were derived from read count data at 86,158 SNPs in 64 samples sequenced on the Illumina GA platform. MOI estimates were derived by PCR at the msp-1 and -2 loci. Significant correlations were observed between the two measures, particularly with the msp-1 locus (P = 5.92×10−5). The FWS metric should be more robust than the PCR-based approach owing to reduced sensitivity to potential locus-specific artifacts. Furthermore the FWS metric captures information on a range of parameters which influence out-crossing risk including the number of clones (MOI), their relative proportions and genetic divergence. This approach should provide novel insights into the factors which correlate with, and shape within-host diversity.  相似文献   
29.
Shade trees are an integral part of most cocoa growing systems across the world. This study assesses farmers’ local knowledge of shade trees at two locations in Ghana with different climatic conditions and vulnerability to climate change. Akumadan is located in the northern dry part of the cocoa belt representing marginal conditions for cocoa cultivation, whereas Asankragua is located in the southern wet part, more ecologically favorable for cocoa cultivation. Inventories were conducted to assess the abundance of species, their structural characteristics and benefits to cocoa systems. Results show that cocoa farmers have detailed knowledge on the functions of shade trees in cocoa systems and prefer species that provide specific needs according to the location. However, abundance of species in a location does not necessary translate into beneficial impacts on cocoa productivity. In the drier part of the cocoa belt, income diversification through shade trees is an adaptation strategy to the increasingly marginal conditions for cocoa production, which has led to the high proportion of fruit trees among the most abundant species. In contrast, farmers in the southern part of the cocoa belt select shade trees for their high cocoa compatibility. Adaptation strategies for cocoa farmers should therefore promote species that best accommodate farmers’ economic, agronomic and environmental needs.  相似文献   
30.

Background

The only available vaccine that could be potentially beneficial against mycobacterial diseases contains live attenuated bovine tuberculosis bacillus (Mycobacterium bovis) also called Bacillus Calmette-Guérin (BCG). Even though the BCG vaccine is still widely used, results on its effectiveness in preventing mycobacterial diseases are partially contradictory, especially regarding Buruli Ulcer Disease (BUD). The aim of this case-control study is to evaluate the possible protective effect of BCG vaccination on BUD.

Methodology

The present study was performed in three different countries and sites where BUD is endemic: in the Democratic Republic of the Congo, Ghana, and Togo from 2010 through 2013. The large study population was comprised of 401 cases with laboratory confirmed BUD and 826 controls, mostly family members or neighbors.

Principal Findings

After stratification by the three countries, two sexes and four age groups, no significant correlation was found between the presence of BCG scar and BUD status of individuals. Multivariate analysis has shown that the independent variables country (p = 0.31), sex (p = 0.24), age (p = 0.96), and presence of a BCG scar (p = 0.07) did not significantly influence the development of BUD category I or category II/III. Furthermore, the status of BCG vaccination was also not significantly related to duration of BUD or time to healing of lesions.

Conclusions

In our study, we did not observe significant evidence of a protective effect of routine BCG vaccination on the risk of developing either BUD or severe forms of BUD. Since accurate data on BCG strains used in these three countries were not available, no final conclusion can be drawn on the effectiveness of BCG strain in protecting against BUD. As has been suggested for tuberculosis and leprosy, well-designed prospective studies on different existing BCG vaccine strains are needed also for BUD.  相似文献   
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