497 research outputs found
Rebuilding after emergency: Revamping agricultural research in Sierra Leone after civil war
"The civil war in Sierra Leone, caused by a mix of political, social, and economic factors, had a huge impact on the overall economy in general and on the performance of the agricultural sector in particular. The agricultural research system of Sierra Leone was severely affected by the civil war. Research infrastructure was destroyed, laboratories were damaged and abandoned, and well-trained researchers and scientists fled from the country. With the cessation of hostilities in 2002, the government of Sierra Leone concentrated its efforts on the resettlement of displaced persons and on social and economic reconstruction. The efforts of the government include the rehabilitation and reorganization of the former National Agricultural Research Coordinating Council (NARCC), which was coordinating agricultural research in Sierra Leone. The Sierra Leone Agricultural Research Institute (SLARI) Act was passed by the parliament of Sierra Leone in 2007 to replace NARCC. As a new organization, SLARI needed to make strategic decisions to guide its operations in order to make it effective in responding to the demands of stakeholders within the food and agriculture system. To provide a focus for SLARI and link its agenda to national development priorities, a strategic plan and operational plan were developed. The methodology used to design the SLARI strategic plan applied an organizational innovation model through which the plan was nested within the strategic plan of the Forum for Agricultural Research in Africa (FARA) and Conseil Ouest et Center Africain pour la Recherche et le Développement Agricoles (CORAF) / West and Central African Council for Agricultural Research and Development (WECARD), and the operational plan was hinged on Comprehensive African Agricultural Development Program (CAADP) and Framework for African Agricultural Productivity (FAAP) principles. This would ensure synergy with regional and subregional strategies. The strategic plan would promote increased coordination, interaction, interlinkages, partnerships, and networks among the various agents associated with agricultural research for development systems in Sierra Leone. It would also help achieve SLARI's vision of increasing food security and wealth among Sierra Leone's rural population. For SLARI to make a meaningful contribution to agricultural development in Sierra Leone, the operational plan must be implemented in such a way that the results envisaged in the strategic plan can be achieved. This requires funds and commitment from all stakeholders, especially the government of Sierra Leone." from authors' abstractwar, Agriculture, Development, Research, Strategic plan, Operational plan, Science and technology, Agricultural research,
Effects of zooplankton size and concentration and light intensity on the feeding behavior of Atlantic mackerel \u3cem\u3eScomber scombrus\u3c/em\u3e
Atlantic mackerel Scomber scombrus had low clearance rates when fed older stage copepodites of the copepod Calanus finmarchicus at high concentrations and high clearance rates at low concentrations. These rates were consistent with filter feeding at high concentrations and particulate feeding at low concentrations. Intermediate and small copepods presented together at high concentrations were cleared at lower rates than the large C. finmarchicus, suggesting lower filtration efficiencies. Intermediate and small copepods were presented over a range of light intensities (8.2 x 10-8 to 1.6 x 100 µE m-2 s-1). Feeding rate did not change significantly between 1.6 x 100 and 2.0 x 10-6 µE m-2 s-1, but decreased to nearly zero at 8.2 x 10-8 µE m-2 s-1, indicating a light intensity threshold for feeding of about 10-7 µE m-2 s-1. This threshold enables mackerel to feed throughout the night near the ocean surface. Swimming speed decreased to a lesser degree than feeding rate at the lowest light intensity, indicating that the change in filter-feeding rate is only partially due to the change in speed. The school dispersed in both low and high light levels, but spacing between fish did not appear to be related to feeding rate
Medical care in the workhouses in Birmingham and Wolverhampton, 1834-1914
This study of the medical role of the urban workhouses of Birmingham and Wolverhampton after the New Poor Law addresses the following questions: what were the standards of medical and nursing practice and what treatments were used to alleviate inmates’ suffering? It considers the nature of illnesses encountered covering acute non-infective illnesses, infectious disease and chronic disability, and highlights the important role the workhouse played in providing institutional care, especially in the isolation of epidemic diseases. Birmingham workhouse had a well-developed medical service prior to the New Poor Law and this continued until the mid-nineteenth century. By comparison, Wolverhampton workhouse did not meet satisfactory levels of medical and nurse staffing until near the end of the century. The study provides a new perspective on medical care in workhouse infirmaries by showing how standards varied over time within the same institution and how medicalisation of the workhouse began in the early years after the New Poor Law. Medical care in workhouses has been viewed as important only in the context of the development of the National Health Service but this study demonstrates that it provided significant, and at times high quality, medical treatment for the poor
Development and optimization of a differentiated airway epithelial cell model of the bovine respiratory tract
Cattle are subject to economically-important respiratory tract infections by various bacterial and viral pathogens and there is an urgent need for the development of more realistic in vitro models of the bovine respiratory tract to improve our knowledge of disease pathogenesis. In the present study, we have optimized the culture conditions in serum-free medium that allow bovine bronchial epithelial cells (BBECs) grown at an air-liquid interface to differentiate into a three-dimensional epithelium that is highly representative of the bovine airway. Epidermal growth factor was required to trigger both proliferation and differentiation of BBECs whilst retinoic acid was also essential for mucociliary differentiation. Triiodothyronine was demonstrated not to be important for the differentiation of BBECs. Oxygen concentration had a minimal effect although optimal ciliation was achieved when BBECs were cultured at 14% oxygen tension. Insert pore-density had a significant effect on the growth and differentiation of BBECs; a high-pore-density was required to trigger optimum differentiation. The established BBEC model will have wide-ranging applications for the study of bacterial and viral infections of the bovine respiratory tract; it will contribute to the development of improved vaccines and therapeutics and will reduce the use of cattle in in vivo experimentation
Augmenter of liver regeneration enhances the success rate of fetal pancreas transplantation in rodents
Background. Treatment of fetal pancreas (FP) isografts with insulin- like growth factor-I greatly improves the rate of conversion to euglycemia in diabetic rats. Complete knowledge of other factors that may facilitate the engraftment and function of FP in vivo is still embryonic. Augmenter of liver regeneration (ALR) is a newly described polypeptide growth factor found in weanling rat livers. ALR has trophic effects on regenerating liver. We studied the effects of in situ administration of this agent on FP isografts in rats. Methods. Streptozotocin-diabetic Lewis rats (blood glucose >300 mg/dl) received 16 FP isografts transplanted intramuscularly. ALR was delivered from day 1 through day 14, in doses of 40 or 400 ng/kg/d. Animals were followed for 3 months with serial weights and blood glucose monitoring. These animals were compared with those treated with vehicle alone. Results. Of the group treated with ALR at 40 ng/kg/day for 14 days, 89% (eight of nine) were euglycemic (P=0.0003). Of the group treated with ALR at 400 ng/kg/day for 14 days, 88% (seven of eight) were euglycemic (P=0.0007). Of the group treated with vehicle alone, none of the six were euglycemic. Euglycemia is defined here as glucose<200 mg/dl for 3 days. Pathology of the intramuscular transplant site showed patches of islet tissue embedded in fat. These patches demonstrated insulin immunoreactivity. Conclusions. Diabetes was reversed in a significantly greater proportion of FP + ALR-treated recipients than those animals treated with vehicle alone. Local delivery of growth factors my be used as an adjunct to FP transplantation to improve the rate of success. This in situ model may be useful to further evaluate other soluble factors
Coagulation factor VIIa binds to herpes simplex virus 1‐encoded glycoprotein C forming a factor X‐enhanced tenase complex oriented on membranes
BackgroundThe cell membrane‐derived initiators of coagulation, tissue factor (TF) and anionic phospholipid (aPL), are constitutive on the herpes simplex virus type 1 (HSV1) surface, bypassing physiological regulation. TF and aPL accelerate proteolytic activation of factor (F) X to FXa by FVIIa to induce clot formation and cell signaling. Thus, infection in vivo is enhanced by virus surface TF. HSV1‐encoded glycoprotein C (gC) is implicated in this tenase activity by providing viral FX binding sites and increasing FVIIa function in solution.ObjectiveTo examine the biochemical influences of gC on FVIIa‐dependent FX activation.MethodsImmunogold electron microscopy (IEM), kinetic chromogenic assays and microscale thermophoresis were used to dissect tenase biochemistry. Recombinant TF and gC were solubilized (s) by substituting the transmembrane domain with poly‐histidine, which could be orientated on synthetic unilamellar vesicles containing Ni‐chelating lipid (Ni‐aPL). These constructs were compared to purified HSV1 TF±/gC ± variants.ResultsIEM confirmed that gC, TF, and aPL are simultaneously expressed on a single HSV1 particle where the contribution of gC to tenase activity required the availability of viral TF. Unlike viral tenase activity, the cofactor effects of sTF and sgC on FVIIa was additive when bound to Ni‐aPL. FVIIa was found to bind to sgC and this was enhanced by FX. Orientation of sgC on a lipid membrane was critical for FVIIa‐dependent FX activation.ConclusionsThe assembly of gC with FVIIa/FX parallels that of TF and may involve other constituents on the HSV1 envelope with implications in virus infection and pathology.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/155933/1/jth14790-sup-0001-Supinfo.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/155933/2/jth14790.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/155933/3/jth14790_am.pd
Parasitic Infection Improves Survival from Septic Peritonitis by Enhancing Mast Cell Responses to Bacteria in Mice
Mammals are serially infected with a variety of microorganisms, including bacteria and parasites. Each infection reprograms the immune system's responses to re-exposure and potentially alters responses to first-time infection by different microorganisms. To examine whether infection with a metazoan parasite modulates host responses to subsequent bacterial infection, mice were infected with the hookworm-like intestinal nematode Nippostrongylus brasiliensis, followed in 2–4 weeks by peritoneal injection of the pathogenic bacterium Klebsiella pneumoniae. Survival from Klebsiella peritonitis two weeks after parasite infection was better in Nippostrongylus-infected animals than in unparasitized mice, with Nippostrongylus-infected mice having fewer peritoneal bacteria, more neutrophils, and higher levels of protective interleukin 6. The improved survival of Nippostrongylus-infected mice depends on IL-4 because the survival benefit is lost in mice lacking IL-4. Because mast cells protect mice from Klebsiella peritonitis, we examined responses in mast cell-deficient KitW-sh/KitW-sh mice, in which parasitosis failed to improve survival from Klebsiella peritonitis. However, adoptive transfer of cultured mast cells to KitW-sh/KitW-sh mice restored survival benefits of parasitosis. These results show that recent infection with Nippostrongylus brasiliensis protects mice from Klebsiella peritonitis by modulating mast cell contributions to host defense, and suggest more generally that parasitosis can yield survival advantages to a bacterially infected host
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