Studies on the role of inflammation and stem cells in cardiac ischaemic injury

The regenerative capacity of human myocardium is unable to compensate adequately forth significant loss of heart muscle that occurs in acute myocardial infarction (Ml). However, recent studies indicate that the adult heart may contain populations of cells that have stem cell characteristics and which could have regenerative potential. In order to better examine the biology of such cells, this study developed a mouse model of MI that combined low mortality, reproducible infarct size and the opportunity for reperfusion studies. One potential barrier to the expression of regenerative capacity at the time of acute Ml is inflammation, which, as well as contributing to myocardial injury, may prevent the activation and function of putative stem cells. The C5/C5a axis in the complement cascade is a key mediator of the inflammatory events involved in MI and therefore represents an attractive target. An antibody to the C5a receptor was used in vivo in the murine model of MI. Although the neutrophil infiltration at the time of MI was significantly reduced (p<0.05), the size of MI was unchanged in comparison to control, suggesting that other regenerative strategies must be explored. Therefore in pursuit of a mechanism by which the heart may regenerate, cells were isolated and assayed in vitro for their stem cell capacity. Cells expressing platelet derived growth factor receptor alpha (PDGFRA) were candidates for such stem cells, both as these are present in the proepicardium and epicardium in the embryo, and that Pdgfra(^+) mice demonstrate cardiac abnormalities. A combined approach was employed, using genetically modified mice expressing Green Fluorescence Protein (GFP) under the transcriptional control of the Pdgfra locus, expression of surface antigens as well as the ability of candidate stem cells to demonstrate self renewal and proliferation in a colony forming unit fibroblast assay (CFU-F). A Sca-1(^+) /PECAM˙/PDGFRA(^GFP+) fraction isolated from the adult heart was found to be enriched for colony forming activity. Two populations were found which formed colonies, the PDGFRA(^GFPHIGH) population which had 'stem cell' like properties in terms of proliferation, prolonged self renewal and multipotent in vitro differentiation, and the PDGFRA (^GFPMEDIUM) population which had 'progenitor cell' like properties in that although it had proliferative ability, the potential of this population to continue to self renew and differentiate into multiple lineages was limited. The number of candidate stem cells and progenitor cells in the heart increased post infarct as evidenced by an increase in number of PDGFRA (^GFPHIGH) and PDGFRA (^GFPMEDIUM) cells, together with a greater colony forming ability of the PDGFRA (^GEPHIGH) cells. These effects were magnified in a proregenerative transgenic model, Pdgfra (^GFP/+) ;mlGF, in which there was over expression of insulin-like growth factor 1 (IGF-1), supporting the argument that Sca-1(^+) /PECAM˙/PDGFRA(^GFP+) cells may have a role to play in the regenerative capacity of the adult heart

Proximate composition of Mystus bleekeri in relation to body size and condition factor from Nala Daik, Sialkot, Pakistan

Proximate composition of small catfish, Mystus bleekeri, from Nala Daik, Sialkot, Pakistan was investigated and fluctuation in relation to body size and condition factor was carried out. Mean percentages for water, fat, protein and ash contents in the whole wet body weight of wild M. bleekeri were 77.87, 3.26, 15.01 and 3.87%, respectively. Body composition of the fish was effected by body size; however, condition factor remains constant with observed body constituents (% water, fat, protein, ash and organic contents). Highly significant (P&lt;0.001) correlation Found between percentage water and percentage fat, protein, ash and organic contents in both wet and dry body weight. Investigation of body size on body constituents Reflected decrease in relative amount of water, skeleton (wet and dry weight), increase in fat (dry weight), protein, organic contents (wet and dry weight), and no effect on fat (wet weight) with growth of fish. Additionally, the first reference for proximate composition for M. bleekeri is provided.Key words: Proximate composition, body size, condition factor, predictive equation, catfish, Mystus bleekeri

Contemporary Issues in Current Account Operations in Pakistani IBs - Sharia Compliant Solution

Contemporary Sharia scholars have three stances about the Current Account Operations in Pakistani Islamic Banks (IBs) i.e., (i) Ijarah based contract (ii) Wadi'ah based contract, and (iii) Qard based contract. This paper is an attempt to delve into the root causes of the differences of scholars and to find the Sharia-compliant solution acceptable for all. Descriptive as well as applied approaches are used in this paper. Clearing of ambiguity on this issue may result in twofold benefits: from the public point of view, it would satisfy practising Muslims which may result in form of huge deposits in this account (ii) from IBs viewpoint the Current Account is a bonus deposit