172 research outputs found
High-nutrition biscuits to increase animal protein in diets of HIV-infected Kenyan women and their children: A study in progress
Author's manuscript.Background. Preliminary evidence suggests that improved nutrition early in HIV infection may delay progression to AIDS and delay the initiation or improve the effectiveness of antiretroviral drug therapy. There are few studies that evaluate food-based interventions in drug-naĂŻve, HIV-infected women and their children. Meat provides several nutrients identified as important in maintaining immune function and lean body mass.
Objective. To design supplemental meat and soybean biscuits for use in a randomized trial examining the effect of meat in the diet of drug-naĂŻve, HIV-infected rural Kenyan women on changes in weight, lean body mass, morbidity, nutritional status, and activities of daily living of the women and growth and development of their children.
Methods. We designed three supplemental biscuits: one with added dried beef, another with added soybean flour, and a wheat biscuit to serve as a control biscuit to be used in a randomized feeding intervention in drug-naĂŻve, HIV-infected rural Kenyan women and their children. The nutritional contents of the different types of biscuit were examined and compared.
Results. The three biscuits were isocaloric. Meat biscuits provided more lysine, vitamin B12, and bioavailable zinc. Soybean biscuits provided more total and absorbable iron; however, higher fiber and phytate contents may inhibit nutrient absorption. Data analysis for clinical outcomes of the trial is ongoing.
Conclusions. The âbiscuit modelâ is useful for nutrition supplementation studies because it can be provided in a blinded and randomized fashion, safely and privately in a home under directly observed consumption by a highly stigmatized population. It is well received by adults and children, and the biscuits can be produced locally with available, simple, affordable technology.NICHD NIH HHS - 1R01HD57646-01A
Morbidity and nutrition status of rural drug-naĂŻve Kenyan women living with HIV
This paper describes morbidity in a group of HIV-positive drug-naĂŻve rural women in western Kenya. A total of 226 drug-naĂŻve HIV-positive women were evaluated for baseline morbidity, immune function, and anthropometry before a food-based nutrition intervention. Kenyan nurses visited women in their homes and conducted semi-structured interviews regarding symptoms and physical signs experienced at the time of the visit and during the previous week and physical inspection. Blood and urine samples were examined for determination of immune function (CD4, CD8, and total lymphocyte counts), anaemia, malaria, and pregnancy status. Intradermal skin testing with tuberculin (PPD), candida, and tetanus toxoid antigens was also performed to evaluate cell-mediated immunity. Anthropometry was measured, and body mass index (BMI) was calculated. Seventy-six per cent of the women reported being sick on the day of the interview or within the previous week. Illnesses considered serious were reported by 13.7% of women. The most frequent morbidity episodes reported were upper respiratory tract infections (13.3%), suspected malaria (5.85%), skeletal pain (4.87%), and stomach pain (4.42%). The most common morbidity signs on physical inspection were respiratory symptoms, most commonly rhinorrhea and coughing. Confirmed malaria and severe diarrhea were significantly associated with a higher BMI
Cerebrospinal Fluid Biomarkers in Cerebral Amyloid Angiopathy: New Data and Quantitative Meta-Analysis
Background To evaluate the diagnostic accuracy of cerebrospinal fluid (CSF) biomarkers in patients with probable cerebral amyloid angiopathy (CAA) according to the modified Boston criteria in a retrospective multicentric cohort. Methods Beta-amyloid 1-40 (AÎČ40), beta-amyloid 1-42 (AÎČ42), total tau (t-tau), and phosphorylated tau 181 (p-tau181) were measured in 31 patients with probable CAA, 28 patients with Alzheimer's disease (AD), and 30 controls. Receiver-operating characteristics (ROC) analyses were performed for the measured parameters as well as the AÎČ42/40 ratio to estimate diagnostic parameters. A meta-analysis of all amenable published studies was conducted. Results In our data AÎČ42/40 (AUC 0.88) discriminated best between CAA and controls while AÎČ40 did not perform well (AUC 0.63). Differentiating between CAA and AD, p-tau181 (AUC 0.75) discriminated best in this study while AÎČ40 (AUC 0.58) and AÎČ42 (AUC 0.54) provided no discrimination. In the meta-analysis, AÎČ42/40 (AUC 0.90) showed the best discrimination between CAA and controls followed by t-tau (AUC 0.79), AÎČ40 (AUC 0.76), and p-tau181 (AUC 0.71). P-tau181 (AUC 0.76), AÎČ40 (AUC 0.73), and t-tau (AUC 0.71) differentiated comparably between AD and CAA while AÎČ42 (AUC 0.54) did not. In agreement with studies examining AD biomarkers, AÎČ42/40 discriminated excellently between AD and controls (AUC 0.92-0.96) in this study as well as the meta-analysis. Conclusion The analyzed parameters differentiate between controls and CAA with clinically useful accuracy (AUC > âŒ0.85) but not between CAA and AD. Since there is a neuropathological, clinical and diagnostic continuum between CAA and AD, other diagnostic markers, e.g., novel CSF biomarkers or other parameters might be more successful
Frequency of deep-seated cerebral microbleeds in patients with lobar hemorrhages and histopathological evidence for cerebral amyloid angiopathy
BackgroundCerebral amyloid angiopathy (CAA) is a common disease and the most common cause of lobar hemorrhages in the elderly. Usually, deep-seated microhemorrhages preclude the diagnosis of CAA. In this study, we sought to estimate the frequency of deep-seated microbleeds on MRI in patients with lobar hemorrhages and histopathological evidence for cerebral amyloid angiopathy. In addition, we describe a cohort of patients with cortical and deep-seated microbleeds on MRI and a histopathological specimen available from lobar hematoma evacuation.MethodsRetrospective database search for histopathological specimens from lobar hematoma evacuation and review of imaging findings (CT and MRI) and patient charts was performed.ResultsBetween 1 January 2012 and 31 December 2020, 88 specimens from 88 patients were available. A total of 56 specimens were excluded (no brain tissue in the specimen n = 4, other diagnosis n = 8, no MRI n = 43, and no BOLD-based sequence n = 1). Of the remaining 32 patients, 25 patients (78%) did not harbor deep-seated lesions on MRI, of which 17 patients had histopathological features of CAA. A total of seven patients harbored deep-seated CMB. Of these seven patients, three (3/20, 15%) had histopathological features of CAA.ConclusionApproximately 15% of patients with histopathologically diagnosed CAA harbor deep-seated microbleeds. This finding may add to the discussion on how to identify patients with CAA and deep-seated CMB
Maternal common mental disorders and infant development in Ethiopia : the P-MaMiE Birth Cohort
Background: Chronicity and severity of early exposure to maternal common mental disorders (CMD) has been associated with poorer infant development in high-income countries. In low- and middle-income countries (LAMICs), perinatal CMD is inconsistently associated with infant development, but the impact of severity and persistence has not been examined. Methods: A nested population-based cohort of 258 pregnant women was identified from the Perinatal Maternal Mental Disorder in Ethiopia (P-MaMiE) study, and 194 (75.2%) were successfully followed up until the infants were 12 months of age. Maternal CMD was measured in pregnancy and at two and 12 months postnatal using the WHO Self-Reporting Questionnaire, validated for use in this setting. Infant outcomes were evaluated using the Bayley Scales of Infant Development. Results: Antenatal maternal CMD symptoms were associated with poorer infant motor development ( ÎČ ^ -0.20; 95% CI: -0.37 to -0.03), but this became non-significant after adjusting for confounders. Postnatal CMD symptoms were not associated with any domain of infant development. There was evidence of a dose-response relationship between the number of time-points at which the mother had high levels of CMD symptoms (SRQ â„ 6) and impaired infant motor development ( ÎČ ^ = -0.80; 95%CI -2.24, 0.65 for ante- or postnatal CMD only, ÎČ ^ = -4.19; 95%CI -8.60, 0.21 for ante- and postnatal CMD, compared to no CMD; test-for-trend Ï213.08(1), p < 0.001). Although this association became non-significant in the fully adjusted model, the ÎČ ^ coefficients were unchanged indicating that the relationship was not confounded. In multivariable analyses, lower socio-economic status and lower infant weight-for-age were associated with significantly lower scores on both motor and cognitive developmental scales. Maternal experience of physical violence was significantly associated with impaired cognitive development. Conclusions: The study supports the hypothesis that it is the accumulation of risk exposures across time rather than early exposure to maternal CMD per se that is more likely to affect child development. Further investigation of the impact of chronicity of maternal CMD upon child development in LAMICs is indicated. In the Ethiopian setting, poverty, interpersonal violence and infant undernutrition should be targets for interventions to reduce the loss of child developmental potential.Peer Reviewe
Sequential Delivery of Host-Induced Virulence Effectors by Appressoria and Intracellular Hyphae of the Phytopathogen Colletotrichum higginsianum
Phytopathogens secrete effector proteins to manipulate their hosts for effective colonization. Hemibiotrophic fungi must maintain host viability during initial biotrophic growth and elicit host death for subsequent necrotrophic growth. To identify effectors mediating these opposing processes, we deeply sequenced the transcriptome of Colletotrichum higginsianum infecting Arabidopsis. Most effector genes are host-induced and expressed in consecutive waves associated with pathogenic transitions, indicating distinct effector suites are deployed at each stage. Using fluorescent protein tagging and transmission electron microscopy-immunogold labelling, we found effectors localised to stage-specific compartments at the host-pathogen interface. In particular, we show effectors are focally secreted from appressorial penetration pores before host invasion, revealing new levels of functional complexity for this fungal organ. Furthermore, we demonstrate that antagonistic effectors either induce or suppress plant cell death. Based on these results we conclude that hemibiotrophy in Colletotrichum is orchestrated through the coordinated expression of antagonistic effectors supporting either cell viability or cell death
Plasticity in dendroclimatic response across the distribution range of Aleppo pine (Pinus halepensis)
We investigated the variability of the climate-growth relationship of Aleppo pine across its distribution range in the Mediterranean Basin. We constructed a network of tree-ring index chronologies from 63 sites across the region. Correlation function analysis identified the relationships of tree-ring index to climate factors for each site. We also estimated the dominant climatic gradients of the region using principal component analysis of monthly, seasonal, and annual mean temperature and total precipitation from 1,068 climatic gridpoints. Variation in ring width index was primarily related to precipitation and secondarily to temperature. However, we found that the dendroclimatic relationship depended on the position of the site along the climatic gradient. In the southern part of the distribution range, where temperature was generally higher and precipitation lower than the regional average, reduced growth was also associated with warm and dry conditions. In the northern part, where the average temperature was lower and the precipitation more abundant than the regional average, reduced growth was associated with cool conditions. Thus, our study highlights the substantial plasticity of Aleppo pine in response to different climatic conditions. These results do not resolve the source of response variability as being due to either genetic variation in provenance, to phenotypic plasticity, or a combination of factors. However, as current growth responses to inter-annual climate variability vary spatially across existing climate gradients, future climate-growth relationships will also likely be determined by differential adaptation and/or acclimation responses to spatial climatic variation. The contribution of local adaptation and/or phenotypic plasticity across populations to the persistence of species under global warming could be decisive for prediction of climate change impacts across populations. In this sense, a more complex forest dynamics modeling approach that includes the contribution of genetic variation and phenotypic plasticity can improve the reliability of the ecological inferences derived from the climate-growth relationships.This work was partially supported by Spanish Ministry of Education and Science co-funded by FEDER program (CGL2012-31668), the European Union and the National Ministry of Education and Religion of Greece (EPEAEK- Environment â Archimedes), the Slovenian Research Agency (program P4-0015), and the USDA Forest Service. The cooperation among international partners was supported by the COST Action FP1106, STREeSS
The next generation neutrino telescope: IceCube-Gen2
The IceCube Neutrino Observatory, a cubic-kilometer-scale neutrino detector at the geographic South Pole, has reached a number of milestones in the field of neutrino astrophysics: the discovery of a high-energy astrophysical neutrino flux, the temporal and directional correlation of neutrinos with a flaring blazar, and a steady emission of neutrinos from the direction of an active galaxy of a Seyfert II type and the Milky Way. The next generation neutrino telescope, IceCube-Gen2, currently under development, will consist of three essential components: an array of about 10,000 optical sensors, embedded within approximately 8 cubic kilometers of ice, for detecting neutrinos with energies of TeV and above, with a sensitivity five times greater than that of IceCube; a surface array with scintillation panels and radio antennas targeting air showers; and buried radio antennas distributed over an area of more than 400 square kilometers to significantly enhance the sensitivity of detecting neutrino sources beyond EeV. This contribution describes the design and status of IceCube-Gen2 and discusses the expected sensitivity from the simulations of the optical, surface, and radio components
Sensitivity of IceCube-Gen2 to measure flavor composition of Astrophysical neutrinos
The observation of an astrophysical neutrino flux in IceCube and its detection capability to separate between the different neutrino flavors has led IceCube to constraint the flavor content of this flux. IceCube-Gen2 is the planned extension of the current IceCube detector, which will be about 8 times larger than the current instrumented volume. In this work, we study the sensitivity of IceCube-Gen2 to the astrophysical neutrino flavor composition and investigate its tau neutrino identification capabilities. We apply the IceCube analysis on a simulated IceCube-Gen2 dataset that mimics the High Energy Starting Event (HESE) classification. Reconstructions are performed using sensors that have 3 times higher quantum efficiency and isotropic angular acceptance compared to the current IceCube optical modules. We present the projected sensitivity for 10 years of data on constraining the flavor ratio of the astrophysical neutrino flux at Earth by IceCube-Gen2
Mechanical design of the optical modules intended for IceCube-Gen2
IceCube-Gen2 is an expansion of the IceCube neutrino observatory at the South Pole that aims to increase the sensitivity to high-energy neutrinos by an order of magnitude. To this end, about 10,000 new optical modules will be installed, instrumenting a fiducial volume of about 8 km3. Two newly developed optical module types increase IceCubeâs current sensitivity per module by a factor of three by integrating 16 and 18 newly developed four-inch PMTs in specially designed 12.5-inch diameter pressure vessels. Both designs use conical silicone gel pads to optically couple the PMTs to the pressure vessel to increase photon collection efficiency. The outside portion of gel pads are pre-cast onto each PMT prior to integration, while the interiors are filled and cast after the PMT assemblies are installed in the pressure vessel via a pushing mechanism. This paper presents both the mechanical design, as well as the performance of prototype modules at high pressure (70 MPa) and low temperature (â40âC), characteristic of the environment inside the South Pole ice
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