Simultaneous point-of-care detection of anemia and sickle cell disease in Tanzania: the RAPID study.

Both anemia and sickle cell disease (SCD) are highly prevalent across sub-Saharan Africa, and limited resources exist to diagnose these conditions quickly and accurately. The development of simple, inexpensive, and accurate point-of-care (POC) assays represents an important advance for global hematology, one that could facilitate timely and life-saving medical interventions. In this prospective study, Robust Assays for Point-of-care Identification of Disease (RAPID), we simultaneously evaluated a POC immunoassay (Sickle SCAN™) to diagnose SCD and a first-generation POC color-based assay to detect anemia. Performed at Bugando Medical Center in Mwanza, Tanzania, RAPID tested 752 participants (age 1 day to 20 years) in four busy clinical locations. With minimally trained medical staff, the SCD POC assay diagnosed SCD with 98.1% sensitivity and 91.1% specificity. The hemoglobin POC assay had 83.2% sensitivity and 74.5% specificity for detection of severe anemia (Hb ≤ 7 g/dL). Interobserver agreement was excellent for both POC assays (r = 0.95-0.96). Results for the hemoglobin POC assay have informed the second-generation assay design to be more suitable for low-resource settings. RAPID provides practical feasibility data regarding two novel POC assays for the diagnosis of anemia and SCD in real-world field evaluations and documents the utility and potential impact of these POC assays for sub-Saharan Africa.

Equine thrombospondin II and secreted protein acidic and cysteine-rich in a model of normal and pathological wound repair.

Wound healing in horses is complicated, particularly when wounds are on the limb. The objectives of this study were to clone equine thrombospondin II (THBS2) and secreted protein acidic and cysteine-rich (SPARC) cDNAs and to compare the spatiotemporal expression of mRNAs and proteins during repair of body and limb wounds. These molecules were targeted in view of their potential biological contribution to angiogenesis, which is exacerbated during the repair of limb wounds in horses. Cloning was achieved by screening size-selected cDNA libraries previously derived from 7-day-old wounds. Expression was studied in unwounded skin and in samples from 1, 2, 3, 4, and 6 wk old wounds of the body and limb. Temporal gene expression was determined by semiquantitative RT-PCR, while protein expression was mapped immunohistochemically. The temporal pattern of expression for both genes was similar; wounding caused immediate upregulation of mRNA, which did not return to baseline by the end of the study, and overexpression was noted in body relative to limb wounds. Immunostaining for THBS2 and SPARC was induced by wounding, though no differences in stain location or intensity were detected between body and limb wounds. This study is the first to characterize equine cDNA for THBS2 and SPARC and to document mRNA expression over the different phases of repair. THBS2 and SPARC might modulate angiogenesis during wound healing in the horse, which could protect against the disproportionate fibroplasia commonly afflicting limb wounds and leading to the development of exuberant granulation tissue.

Equine lumican (LUM) cDNA sequence and spatio-temporal expression in an experimental model of normal and pathological wound healing.

The development of exuberant granulation tissue, a situation that in some ways resembles the human keloid, compromises both the aesthetic and functional outcomes of wound repair in horses. To help elucidate the underlying molecular mechanisms the spatio-temporal expression of lumican (LUM) mRNA and protein for their potential contributions to tissue remodelling of body and limb wounds, was examined in an established experimental model. Expression was studied in intact skin and in samples of 1-, 2-, 3-, 4- and 6-week-old wounds of the body and forelimb. Temporal gene expression was determined by reverse transcriptase polymerase chain reaction, and protein expression was mapped immunohistochemically. A significant increase in LUM mRNA expression was observed in response to wounding at both anatomical locations, and a significantly higher mRNA level was recorded in thoracic than in limb wounds at weeks 1, 3 and 6 of repair. The immunohistochemical observations partially corroborated the mRNA data. To the authors' knowledge this study is the first to document that the cDNA for LUM is expressed over the different phases of wound repair in horses and suggests that LUM might be involved in both inflammation and remodelling in response to dermal injury. Further studies are now required to verify and quantify the temporal expression of this protein to provide the basis for targeted therapies that might prevent the development of exuberant granulation tissue in horse wound repair.