18 research outputs found
Risk factors for presentation to hospital with severe anaemia in Tanzanian children: a case-control study.
In malaria endemic areas anaemia is a usually silent condition that nevertheless places a considerable burden on health services. Cases of severe anaemia often require hospitalization and blood transfusions. The objective of this study was to assess risk factors for admission with anaemia to facilitate the design of anaemia control programmes. We conducted a prospective case-control study of children aged 2-59 months admitted to a district hospital in southern Tanzania. There were 216 cases of severe anaemia [packed cell volume (PCV) < 25%] and 234 age-matched controls (PCV > or = 25%). Most cases [55.6% (n = 120)] were < 1 year of age. Anaemia was significantly associated with the educational level of parents, type of accommodation, health-seeking behaviour, the child's nutritional status and recent and current medical history. Of these, the single most important factor was Plasmodium falciparum parasitaemia [OR 4.3, 95% confidence interval (CI) 2.9-6.5, P < 0.001]. Multivariate analysis showed that increased recent health expenditure [OR 2.2 (95% CI 1.3-3.9), P = 0.005], malnutrition [OR 2.4 (95%CI 1.3-4.3), P < 0.001], living > 10 km from the hospital [OR 3.0 (95% CI 1.9-4.9), P < 0.001], a history of previous blood transfusion [OR 3.8 (95% CI 1.7-9.1), P < 0.001] and P. falciparum parasitaemia [OR 9.5 (95% CI 4.3-21.3), P < 0.001] were independently related to risk of being admitted with anaemia. These findings are considered in terms of the pathophysiological pathway leading to anaemia. The concentration of anaemia in infants and problems of access to health services and adequate case management underline the need for targeted preventive strategies for anaemia control
Malaria illness mediated by anaemia lessens cognitive development in younger Ugandan children
BACKGROUND: Asymptomatic falciparum malaria is associated with poorer cognitive performance in African schoolchildren and intermittent preventive treatment of malaria improves cognitive outcomes. However, the developmental benefits of chemoprevention in early childhood are unknown. Early child development was evaluated as a major outcome in an open-label, randomized, clinical trial of anti-malarial chemoprevention in an area of intense, year-round transmission in Uganda. METHODS: Infants were randomized to one of four treatment arms: no chemoprevention, daily trimethoprim–sulfamethoxazole, monthly sulfadoxine–pyrimethamine, or monthly dihydroartemisinin–piperaquine (DP), to be given between enrollment (4–6 mos) and 24 months of age. Number of malaria episodes, anaemia (Hb < 10) and neurodevelopment [Mullen Scales of Early Learning (MSEL)] were assessed at 2 years (N = 469) and at 3 years of age (N = 453); at enrollment 70 % were HIV-unexposed uninfected (HUU) and 30 % were HIV-exposed uninfected (HEU). RESULTS: DP was highly protective against malaria and anaemia, although trial arm was not associated with MSEL outcomes. Across all treatment arms, episodes of malarial illness were negatively predictive of MSEL cognitive performance both at 2 and 3 years of age (P = 0.02). This relationship was mediated by episodes of anaemia. This regression model was stronger for the HEU than for the HUU cohort. Compared to HUU, HEU was significantly poorer on MSEL receptive language development irrespective of malaria and anaemia (P = 0.01). CONCLUSIONS: Malaria with anaemia and HIV exposure are significant risk factors for poor early childhood neurodevelopment in malaria-endemic areas in rural Africa. Because of this, comprehensive and cost/effective intervention is needed for malaria prevention in very young children in these settings
Percolation network of organo-modified layered double hydroxide platelets into polystyrene showing enhanced rheological and dielectric behavior
International audienceA hybrid organic inorganic layered double hydroxide incorporating 2-acrylamido-2-methyl-1-propane sulfonic acid (AMPS) is characterized by means of XRD, FTIR, and XPS. The in situ polymerization is scrutinized by 13C CPMAS as well as by a set of XRD experiments with varying temperature. It is found that the in situ polymerization is complete at 200 °C, and the hybrid framework sustains temperatures as high as 350 °C. Direct incorporation of poly(AMPS) is reported and the resulting hybrid LDH phases studied. Subsequently, all generated hybrid platelets are used as organo-modified 2D-type filler dispersed into polystyrene (PS). An immiscible PS composite structure with salient gel-like viscoelastic properties is obtained after bulk polymerization. In the low-frequency region, the typical Newtonian flow behaviour of PS is found to change progressively against filler loading into a shear-thinning behaviour evidenced by a pseudo-plateau in the elastic and loss modulus curves and associated with a shift of the glass transition temperature of PS to higher temperature. It is interpreted by hybrid LDH platelet domains presenting a large interface with the polymer, thus having the effect of restricting the plastic deformation by obstructing polymer chain motion. Such dispersed hybrid LDH tactoids forming a three-dimensional percolated network are indirectly evidenced by the enhancement of the dielectric properties illustrated by an increase in bulk dc conductivity of about one order at room temperature and in the dissipation factor. The study shows that hybrid LDH assembly is of relevance in topical applications regarding mechanical reinforcement as well as electrostatic energy dissipation. © 2010 The Royal Society of Chemistry
Inequality in mortality between Black and White Americans by age, place, and cause and in comparison to Europe, 1990 to 2018
: Although there is a large gap between Black and White American life expectancies, the gap fell 48.9% between 1990 and 2018, mainly due to mortality declines among Black Americans. We examine age-specific mortality trends and racial gaps in life expectancy in high- and low-income US areas and with reference to six European countries. Inequalities in life expectancy are starker in the United States than in Europe. In 1990, White Americans and Europeans in high-income areas had similar overall life expectancy, while life expectancy for White Americans in low-income areas was lower. However, since then, even high-income White Americans have lost ground relative to Europeans. Meanwhile, the gap in life expectancy between Black Americans and Europeans decreased by 8.3%. Black American life expectancy increased more than White American life expectancy in all US areas, but improvements in lower-income areas had the greatest impact on the racial life expectancy gap. The causes that contributed the most to Black Americans' mortality reductions included cancer, homicide, HIV, and causes originating in the fetal or infant period. Life expectancy for both Black and White Americans plateaued or slightly declined after 2012, but this stalling was most evident among Black Americans even prior to the COVID-19 pandemic. If improvements had continued at the 1990 to 2012 rate, the racial gap in life expectancy would have closed by 2036. European life expectancy also stalled after 2014. Still, the comparison with Europe suggests that mortality rates of both Black and White Americans could fall much further across all ages and in both high-income and low-income areas
Tumor cells hijack macrophage-produced complement C1q to promote tumor growth
Clear-cell renal cell carcinoma (ccRCC) possesses an unmet medical need, particularly at the metastatic stage, when surgery is ineffective. Complement is a key factor in tissue inflammation, favoring cancer progression through the production of complement component 5a (C5a). However, the activation pathways that generate C5a in tumors remain obscure. By data mining, we identified ccRCC as a cancer type expressing concomitantly high expression of the components that are part of the classical complement pathway. To understand how the complement cascade is activated in ccRCC and impacts patients' clinical outcome, primary tumors from three patient cohorts (n = 106, 154, and 43), ccRCC cell lines, and tumor models in complement-deficient mice were used. High densities of cells producing classical complement pathway components C1q and C4 and the presence of C4 activation fragment deposits in primary tumors correlated with poor prognosis. The in situ orchestrated production of C1q by tumor-associated macrophages (TAM) and C1r, C1s, C4, and C3 by tumor cells associated with IgG deposits, led to C1 complex assembly, and complement activation. Accordingly, mice deficient in C1q, C4, or C3 displayed decreased tumor growth. However, the ccRCC tumors infiltrated with high densities of C1q-producing TAMs exhibited an immunosuppressed microenvironment, characterized by high expression of immune checkpoints (i.e., PD-1, Lag-3, PD-L1, and PD-L2). Our data have identified the classical complement pathway as a key inflammatory mechanism activated by the cooperation between tumor cells and TAMs, favoring cancer progression, and highlight potential therapeutic targets to restore an efficient immune reaction to cancer