Background: Plasmodium falciparum can cause a diffuse encephalopathy known as cerebral malaria (CM), a major contributor to malaria associated mortality. Despite treatment, mortality due to CM can be as high as 30% while 10% of survivors of the disease may experience short-and long-term neurological complications. The pathogenesis of CM and other forms of severe malaria is multi-factorial and appear to involve cytokine and chemokine homeostasis, inflammation and vascular injury/repair. Identification of prognostic markers that can predict CM severity will enable development of better intervention.

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Transplantation of collagenous matrix from the rat diaphyseal bone to subcutaneous sites resulted in new bone formation by an endochondral sequence. Functional bone marrow develops within the newly formed ossicle. On day 1, the implanted matrix was a discrete conglomerate with fibrin clot and polymorphonuclear leukocytes. By day 3, the leukocytes disappeared, and this event was followed by migration and close apposition of fibroblast cell surface to the collagenous matrix. This initial matrix-membrane interaction culminated in differentiation of fibroblasts to chondroblasts and osteoblasts. The calcification of the hypertrophied chondrocytes and new bone formation were correlated with increased alkaline phosphatase activity and 4sCa incorporation. The ingrowth of capillaries on day 9 resulted in chondrolysis and osteogenesis. Further remodelling of bony trabeculae by osteoclasts resulted in an ossicle of cancellous bone. This was followed by emergence of extravascular islands of hemocytoblasts and their differentiation into functional bone marrow with erythropoietic and granulopoietic elements and megakaryocytes in the ossicle. The onset and maintenance of erythropoiesis in the induced bone marrow were monitored by 5'Fe incorporation into protein-bound heme. These findings imply a role for extracellular collagenous matrix in cell differentiation.There is growing knowledge about the intracellular molecules involved in cell differentiation (8). However, information pertaining to the possible role of extracellular matrix macromolecules such as collagen and proteoglycans has lagged (20). A characteristic feature of multicellular metazoa is the presence of extracellular matrix. In skeletal and dental tissues, extracellular matrices are most prominent and may provide important clues to their role.On contact with demineralized collagenous matrices of bone and tooth, responding fibroblasts (mesenchymal cells) show an alteration of gene expression which results in emergence of new phenotypes (18,19,22,32,33). Simple techniques to study this phenomenon were developed and the temporal sequence of events were delineated (22).

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Abstract. Pregnancy in sickle cell disease (SCD) patients is associated with increased risk of maternal and fetal mortality. This study determines pregnancy outcomes among women with SCD delivering at Korle-Bu Teaching Hospital, Accra, Ghana. Nine hundred sixty (960) medical records of pregnant women (131 HbSS, 112 HbSC, and 717 comparison group) from 2007 to 2008 were reviewed. The HbSS women were at increased risk of eclampsia (adjusted odds ratio [AOR] = 10.56, 95% confidence interval [CI] = 3.60-30.96, P 0.001), intrauterine growth restriction (AOR = 4.00, 95% CI = 1.38-11.64, P = 0.011), and placenta previa (AOR = 22.03, 95% CI = 9.87-49.14, P 0.001) compared with the comparison group. The HbSC women had increased risk for intrauterine fetal death (AOR = 3.38, 95% CI = 1.15-9.96, P = 0.027) and decreased risk of delivering low birth weight babies (AOR = 0.21, 95% CI = 0.06-0.73, P = 0.014). Women with SCD in Ghana are at a greater risk of morbidity and mortality in pregnancy compared with women without hemoglobinopathies. Improved maternal and fetal outcomes in Ghanaian women with SCD can be achieved through effective intervention by health care providers with thorough knowledge about predisposing factors toward adverse outcomes.

SYNOPSIS. With the technique of preselecting pure suspensions of trypanosomes for subsequent electron microscopy and with epoxy resin embedding after glutaraldehyde fixation, we have re‐examined the ultrastructure of Trypanosoma lewisi with particular reference to the flagellum and pellicle. The peripheral flagellar tubules exhibit clockwise asymmetry; however, sub‐tubule B of the peripheral tubules is divided into a doublet by a diagonally running anti‐clockwise arm that originates from the median diaphragm. Projections which seem to be continuous with the counter‐clockwise arms extend into a “basket shaped” intra‐flagellar structure. This structure, originating distal to the flagellar pocket and running anteriorly within the flagellar membrane, may play a role in maintaining the rigidity of the flagellum. The central flagellar tubules have a double helical substructure and dense cross‐striae (diameter 50 Å), and are regularly arranged at distances of approximately 250 Å. The central tubules arise from separate kinetosomal plates that lie at two different elevations. One central flagellar tubule originates from a flattened kinetosomal plate which makes contact with the peripheral tubules. The other central tubule passes through the flattened plate to fuse with an underlying “disc‐like” plate. The primary kinetosome exhibits the uniform triplet pattern of tubules at its most proximal region. A pair of tubules closely associated with one of the triplets represents two of the four subpellicular tubules which penetrate the cytoplasm in the region of the flagellar pocket. Sub‐pellicular tubules of dimensions similar to the flagellar tubules form a uniform cytoskeleton in all regions of the cell except in the area of the flagellar pocket. A desmosome‐like structure maintains continual cell membrane contact with the flagellum and the pellicle. This structure is designated the attachment zone. The fine structure of the kinetoplast is demonstrated. The dense intra‐mitochondrial elements (presumably containing DNA) are actually tubules, embedded in a moderately dense matrix. Morphological observations indicate that this organelle is probably primarily concerned with the ontogenesis of mitochondria, and several mitochondria extend from it into the cytoplasm of the cell.

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