81 research outputs found
A cash-based intervention and the risk of acute malnutrition in children aged 6-59 months living in internally displaced persons camps in Mogadishu, Somalia: A non-randomised cluster trial.
BACKGROUND: Somalia has been affected by conflict since 1991, with children aged <5 years presenting a high acute malnutrition prevalence. Cash-based interventions (CBIs) have been used in this context since 2011, despite sparse evidence of their nutritional impact. We aimed to understand whether a CBI would reduce acute malnutrition and its risk factors. METHODS AND FINDINGS: We implemented a non-randomised cluster trial in internally displaced person (IDP) camps, located in peri-urban Mogadishu, Somalia. Within 10 IDP camps (henceforth clusters) selected using a humanitarian vulnerability assessment, all households were targeted for the CBI. Ten additional clusters located adjacent to the intervention clusters were selected as controls. The CBI comprised a monthly unconditional cash transfer of US29.60 (95% CI 3.51; 55.68), increase the household Food Consumption Score by 14.8 (95% CI 4.83; 24.8), and decrease the Reduced Coping Strategies Index by 11.6 (95% CI 17.5; 5.96). The study limitations were as follows: the study was not randomised, insecurity in the field limited the household cohort sample size and collection of other anthropometric measurements in the child cohort, the humanitarian vulnerability assessment data used to allocate the intervention were not available for analysis, food market data were not available to aid results interpretation, and the malnutrition incidence observed was lower than expected. CONCLUSIONS: The CBI appeared to improve beneficiaries' wealth and food security but did not appear to reduce acute malnutrition risk in IDP camp children. Further studies are needed to assess whether changing this intervention, e.g., including specific nutritious foods or social and behaviour change communication, would improve its nutritional impact. TRIAL REGISTRATION: ISRCTN Registy ISRCTN29521514
High Frequency of Cytomegalovirus-Specific Cytotoxic T-Effector Cells in HLA-A*0201-Positive Subjects during Multiple Viral Coinfections
How the cellular immune response copes with diverse antigenic competition is poorly understood. Responses of virus-specific cytotoxic T lymphocytes (CTL) were examined longitudinally in an individual coinfected with human immunodeficiency virus type 1 (HIV-1), Epstein-Barr virus (EBV), and cytomegalovirus (CMV). CTL responses to all 3 viruses were quantified by limiting dilution analysis and staining with HLA-A*0201 tetrameric complexes folded with HIV-1, EBV, and CMV peptides. A predominance of CMV-pp65-speciflc CTL was found, with a much lower frequency of CTL to HIV-1 Gag and Pol and to EBV-BMLF1 and LMP2. The high frequency of CMV-speciflc CTL, compared with HIV-1- and EBV-specific CTL, was confirmed in an additional 16 HLA-A*0201-positive virus-coinfected subjects. Therefore, the human immune system can mount CTL responses to multiple viral antigens simultaneously, albeit with different strength
Design and Construction of Absorption Cells for Precision Radial Velocities in the K Band using Methane Isotopologues
We present a method to optimize absorption cells for precise wavelength
calibration in the near-infrared. We apply it to design and optimize methane
isotopologue cells for precision radial velocity measurements in the K band. We
also describe the construction and installation of two such cells for the
CSHELL spectrograph at NASA's IRTF. We have obtained their high-resolution
laboratory spectra, which we can then use in precision radial velocity
measurements and which can also have other applications. In terms of obtainable
RV precision methane should out-perform other proposed cells, such as the
ammonia cell (NH) recently demonstrated on CRIRES/VLT. The
laboratory spectra of Ammonia and the Methane cells show strong absorption
features in the H band that could also be exploited for precision Doppler
measurements. We present spectra and preliminary radial velocity measurements
obtained during our first-light run. These initial results show that a
precision down to 20-30 m s can be obtained using a wavelength interval
of only 5 nm in the K band and S/N150. This supports the prediction that
a precision down to a few m s can be achieved on late M dwarfs using the
new generation of NIR spectrographs, thus enabling the detection of terrestrial
planets in their habitable zones. Doppler measurements in the NIR can also be
used to mitigate the radial velocity jitter due to stellar activity enabling
more efficient surveys on young active stars.Comment: accepted PASP, Apr 2012 (in press). Preprint version with 36 pages, 9
Figures, 2 Table
Protemic identification of Germline Proteins in Caenorhabditis elegans
Sexual reproduction involves fusion of 2 haploid gametes to form diploid offspring with genetic contributions from both parents. Gamete formation represents a unique developmental program involving the action of numerous germline-specific proteins. In an attempt to identify novel proteins involved in reproduction and embryonic development, we have carried out a proteomic characterization of the process in Caenorhabditis elegans. To identify candidate proteins, we used 2D gel electrophoresis (2DGE) to compare protein abundance in nucleus-enriched extracts from wild-type C. elegans, and in extracts from mutant worms with greatly reduced gonads (glp-4(bn2) worms reared at 25°C); 84 proteins whose abundance correlated with germline presence were identified. To validate candidates, we used feeding RNAi to deplete candidate proteins, and looked for reduction in fertility and/or germline cytological defects. Of 20 candidates so screened for involvement in fertility, depletion of 13 (65%) caused a significant reduction in fertility, and 6 (30%) resulted in sterility (\u3c5 % of wild-type fertility). Five of the 13 proteins with demonstrated roles in fertility have not previously been implicated in germline function. The high frequency of defects observed after RNAi depletion of candidate proteins suggests that this approach is effective at identifying germline proteins, thus contributing to our understanding of this complex organ
Early Hypothalamic FTO Overexpression in Response to Maternal Obesity – Potential Contribution to Postweaning Hyperphagia
Intrauterine and postnatal overnutrition program hyperphagia, adiposity and glucose intolerance in offspring. Single-nucleotide polymorphisms (SNPs) of the fat mass and obesity associated (FTO) gene have been linked to increased risk of obesity. FTO is highly expressed in hypothalamic regions critical for energy balance and hyperphagic phenotypes were linked with FTO SNPs. As nutrition during fetal development can influence the expression of genes involved in metabolic function, we investigated the impact of maternal obesity on FTO.Female Sprague Dawley rats were exposed to chow or high fat diet (HFD) for 5 weeks before mating, throughout gestation and lactation. On postnatal day 1 (PND1), some litters were adjusted to 3 pups (vs. 12 control) to induce postnatal overnutrition. At PND20, rats were weaned onto chow or HFD for 15 weeks. FTO mRNA expression in the hypothalamus and liver, as well as hepatic markers of lipid metabolism were measured.At weaning, hypothalamic FTO mRNA expression was increased significantly in offspring of obese mothers and FTO was correlated with both visceral and epididymal fat mass (P<0.05); body weight approached significance (P = 0.07). Hepatic FTO and Fatty Acid Synthase mRNA expression were decreased by maternal obesity. At 18 weeks, FTO mRNA expression did not differ between groups; however body weight was significantly correlated with hypothalamic FTO. Postnatal HFD feeding significantly reduced hepatic Carnitine Palmitoyltransferase-1a but did not affect the expression of other hepatic markers investigated. FTO was not affected by chronic HFD feeding.Maternal obesity significantly impacted FTO expression in both hypothalamus and liver at weaning. Early overexpression of hypothalamic FTO correlated with increased adiposity and later food intake of siblings exposed to HFD suggesting upregulation of FTO may contribute to subsequent hyperphagia, in line with some human data. No effect of maternal obesity was observed on FTO in adulthood
A high-precision near-infrared survey for radial velocity variable low-mass stars using CSHELL and a methane gas cell
We present the results of a precise near-infrared (NIR) radial velocity (RV) survey of 32 low-mass stars with spectral types K2-M4 using CSHELL at the NASA InfraRed Telescope Facility in the K band with an isotopologue methane gas cell to achieve wavelength calibration and a novel, iterative RV extraction method. We surveyed 14 members of young (≈25-150 Myr) moving groups, the young field star ϵ Eridani, and 18 nearby (<25 pc) low-mass stars and achieved typical single-measurement precisions of 8-15 m s-1with a long-term stability of 15-50 m s-1 over longer baselines. We obtain the best NIR RV constraints to date on 27 targets in our sample, 19 of which were never followed by high-precision RV surveys. Our results indicate that very active stars can display long-term RV variations as low as ∼25-50 m s-1 at ≈2.3125 μm, thus constraining the effect of jitter at these wavelengths. We provide the first multiwavelength confirmation of GJ 876 bc and independently retrieve orbital parameters consistent with previous studies. We recovered RV variabilities for HD 160934 AB and GJ 725 AB that are consistent with their known binary orbits, and nine other targets are candidate RV variables with a statistical significance of 3σ-5σ. Our method, combined with the new iSHELL spectrograph, will yield long-term RV precisions of ≲5 m s-1 in the NIR, which will allow the detection of super-Earths near the habitable zone of mid-M dwarfs
ICDP workshop on the Lake Tanganyika Scientific Drilling Project: a late Miocene–present record of climate, rifting, and ecosystem evolution from the world's oldest tropical lake
The Neogene and Quaternary are characterized by enormous changes in global climate and environments, including global cooling and the establishment of northern high-latitude glaciers. These changes reshaped global ecosystems, including the emergence of tropical dry forests and savannahs that are found in Africa today, which in turn may have influenced the evolution of humans and their ancestors. However, despite decades of research we lack long, continuous, well-resolved records of tropical climate, ecosystem changes, and surface processes necessary to understand their interactions and influences on evolutionary processes. Lake Tanganyika, Africa, contains the most continuous, long continental climate record from the mid-Miocene (∼10 Ma) to the present anywhere in the tropics and has long been recognized as a top-priority site for scientific drilling. The lake is surrounded by the Miombo woodlands, part of the largest dry tropical biome on Earth. Lake Tanganyika also harbors incredibly diverse endemic biota and an entirely unexplored deep microbial biosphere, and it provides textbook examples of rift segmentation, fault behavior, and associated surface processes. To evaluate the interdisciplinary scientific opportunities that an ICDP drilling program at Lake Tanganyika could offer, more than 70 scientists representing 12 countries and a variety of scientific disciplines met in Dar es Salaam, Tanzania, in June 2019. The team developed key research objectives in basin evolution, source-to-sink sedimentology, organismal evolution, geomicrobiology, paleoclimatology, paleolimnology, terrestrial paleoecology, paleoanthropology, and geochronology to be addressed through scientific drilling on Lake Tanganyika. They also identified drilling targets and strategies, logistical challenges, and education and capacity building programs to be carried out through the project. Participants concluded that a drilling program at Lake Tanganyika would produce the first continuous Miocene–present record from the tropics, transforming our understanding of global environmental change, the environmental context of human origins in Africa, and providing a detailed window into the dynamics, tempo and mode of biological diversification and adaptive radiations.© Author(s) 2020. This open access article is distributed under
the Creative Commons Attribution 4.0 License
The ability of genetically lean or fat slow-growing chickens to synthesize and store lipids is not altered by the dietary energy source
The increasing use of unconventional feedstuffs in chicken's diets results in the substitution of starch by lipids as the main dietary energy source. To evaluate the responses of genetically fat or lean chickens to these diets, males of two experimental lines divergently selected for abdominal fat content were fed isocaloric, isonitrogenous diets with either high lipid (80 g/kg), high fiber (64 g/kg) contents (HL), or low lipid (20 g/kg), low fiber (21 g/kg) contents (LL) from 22 to 63 days of age. The diet had no effect on growth performance and did not affect body composition evaluated at 63 days of age. Glycolytic and oxidative energy metabolisms in the liver and glycogen storage in liver and Sartorius muscle at 63 days of age were greater in chicken fed LL diet compared with chicken fed HL diet. In Pectoralis major (PM) muscle, energy metabolisms and glycogen content were not different between diets. There were no dietary-associated differences in lipid contents of the liver, muscles and abdominal fat. However, the percentages of saturated (SFA) and monounsaturated fatty acids (MUFA) in tissue lipids were generally higher, whereas percentages of polyunsaturated fatty acids (PUFA) were lower for diet LL than for diet HL. The fat line had a greater feed intake and average daily gain, but gain to feed ratio was lower in that line compared with the lean line. Fat chickens were heavier than lean chickens at 63 days of age. Their carcass fatness was higher and their muscle yield was lower than those of lean chickens. The oxidative enzyme activities in the liver were lower in the fat line than in the lean line, but line did not affect energy metabolism in muscles. The hepatic glycogen content was not different between lines, whereas glycogen content and glycolytic potential were higher in the PM muscle of fat chickens compared with lean chickens. Lipid contents in the liver, muscles and abdominal fat did not differ between lines, but fat chickens stored less MUFA and more PUFA in abdominal fat and muscles than lean chickens. Except for the fatty acid composition of liver and abdominal fat, no interaction between line and diet was observed. In conclusion, the amount of lipids stored in muscles and fatty tissues by lean or fat chickens did not depend on the dietary energy source
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