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Within the healthy population, there is substantial, heritable, and interindividual variability in the platelet response. We explored whether a proportion of this variability could be accounted for by interindividual variation in gene expression. Through a correlative analysis of genome-wide platelet RNA expression data from 37 subjects representing the normal range of platelet responsiveness within a cohort of 500 subjects, we identified 63 genes in which transcript levels correlated with variation in the platelet response to adenosine diphosphate and/or the collagen-mimetic peptide, cross-linked collagen-related peptide. Many of these encode proteins with no reported function in platelets. An association study of 6 of the 63 genes in 4235 cases and 6379 controls showed a putative association with myocardial infarction for COMMD7 (COMM domain-containing protein 7) and a major deviation from the null hypo thesis for LRRFIP1 [leucine-rich repeat (in FLII) interacting protein 1]. Morpholino-based silencing in Danio rerio identified a modest role for commd7 and a significant effect for lrrfip1 as positive regulators of thrombus formation. Proteomic analysis of human platelet LRRFIP1-interacting proteins indicated that LRRFIP1 functions as a component of the platelet cytoskeleton, where it interacts with the actin-remodeling proteins Flightless-1 and Drebrin. Taken together, these data reveal novel proteins regulating the platelet response.

Within the healthy population, there is substantial, heritable, and interindividual variability in the platelet response. We explored whether a proportion of this variability could be accounted for by interindividual variation in gene expression. Through a correlative analysis of genome-wide platelet RNA expression data from 37 subjects representing the normal range of platelet responsiveness within a cohort of 500 subjects, we identified 63 genes in which transcript levels correlated with variation in the platelet response to adenosine diphosphate and/or the collagen-mimetic peptide, cross-linked collagen-related peptide. Many of these encode proteins with no reported function in platelets. An association study of 6 of the 63 genes in 4235 cases and 6379 controls showed a putative association with myocardial infarction for COMMD7(COMM domain-containing protein 7) and a major deviation from the null hypo thesis for LRRFIP1[leucine-rich repeat (in FLII) interacting protein 1]. Morpholino-based silencing in Danio rerioidentified a modest role for commd7and a significant effect for lrrfip1as positive regulators of thrombus formation. Proteomic analysis of human platelet LRRFIP1-interacting proteins indicated that LRRFIP1 functions as a component of the platelet cytoskeleton, where it interacts with the actin-remodeling proteins Flightless-1 and Drebrin. Taken together, these data reveal novel proteins regulating the platelet response.

In this study, we demonstrate the suitability of the vertebrate Danio rerio(zebrafish) for functional screening of novel platelet genes in vivo by reverse genetics. Comparative transcript analysis of platelets and their precursor cell, the megakaryocyte, together with nucleated blood cell elements, endothelial cells, and erythroblasts, identified novel platelet membrane proteins with hitherto unknown roles in thrombus formation. We determined the phenotype induced by antisense morpholino oligonucleotide (MO)–based knockdown of 5 of these genes in a laser-induced arterial thrombosis model. To validate the model, the genes for platelet glycoprotein (GP) IIb and the coagulation protein factor VIII were targeted. MO-injected fish showed normal thrombus initiation but severely impaired thrombus growth, consistent with the mouse knockout phenotypes, and concomitant knockdown of both resulted in spontaneous bleeding. Knockdown of 4 of the 5 novel platelet proteins altered arterial thrombosis, as demonstrated by modified kinetics of thrombus initiation and/or development. We identified a putative role for BAMBI and LRRC32 in promotion and DCBLD2 and ESAM in inhibition of thrombus formation. We conclude that phenotypic analysis of MO-injected zebrafish is a fast and powerful method for initial screening of novel platelet proteins for function in thrombosis.

In this study, we demonstrate the suitability of the vertebrate Danio rerio (zebrafish) for functional screening of novel platelet genes in vivo by reverse genetics. Comparative transcript analysis of platelets and their precursor cell, the megakaryocyte, together with nucleated blood cell elements, endothelial cells, and erythroblasts, identified novel platelet membrane proteins with hitherto unknown roles in thrombus formation. We determined the phenotype induced by antisense morpholino oligonucleotide (MO)–based knockdown of 5 of these genes in a laser-induced arterial thrombosis model. To validate the model, the genes for platelet glycoprotein (GP) IIb and the coagulation protein factor VIII were targeted. MO-injected fish showed normal thrombus initiation but severely impaired thrombus growth, consistent with the mouse knockout phenotypes, and concomitant knockdown of both resulted in spontaneous bleeding. Knockdown of 4 of the 5 novel platelet proteins altered arterial thrombosis, as demonstrated by modified kinetics of thrombus initiation and/or development. We identified a putative role for BAMBI and LRRC32 in promotion and DCBLD2 and ESAM in inhibition of thrombus formation. We conclude that phenotypic analysis of MO-injected zebrafish is a fast and powerful method for initial screening of novel platelet proteins for function in thrombosis.

A poorly functioning tumor vasculature is pro-oncogenic and may impede the delivery of therapeutics. Normalizing the vasculature, therefore, may be beneficial. We previously reported that the secreted glycoprotein leucine-rich α-2-glycoprotein 1 (LRG1) contributes to pathogenic neovascularization. Here, we investigate whether LRG1 in tumors is vasculopathic and whether its inhibition has therapeutic utility.

Glycoprotein (GP) VI is the major receptor responsible for platelet activation by collagen, but the collagen-binding surface of GPVI is unknown. To address this issue we expressed, from insect cells, the immunoglobulin (Ig)–like ectodomains (residues 1-185) of human and murine GPVI, called hD1D2 and mD1D2, respectively. Both proteins bound specifically to collagen-related peptide (CRP), a GPVI-specific ligand, but hD1D2 bound CRP more strongly than did mD1D2. Molecular modeling and sequence comparison identified key differences between hD1D2 and mD1D2. Ten mutant hD1D2s were expressed, of which 4 had human residues replaced by their murine counterpart, and 6 had replacements by alanine. CRP binding studies with these mutants demonstrated that the exchange of lysine at position 59 for the corresponding murine glutamate substantially reduced binding to CRP. The position of lysine59 on the apical surface of GPVI suggests a mode of CRP binding analogous to that used by the related killer cell Ig-like receptors to bind HLA. This surface was confirmed as critical for collagen binding by epitope mapping of an inhibitory phage antibody against GPVI. This anti-GPVI, clone 10B12, gave dose-dependent inhibition of the hD1D2-collagen interaction. Clone 10B12 inhibited activation of platelets by CRP and collagen in aggregometry and thrombus formation by the latter in whole blood perfusion. Antibody 10B12 showed significantly reduced binding to the hD1D2-E59, and, on that basis, the GPVI:10B12 interface was modeled.

Glycoprotein (GP) VI is the major receptor responsible for platelet activation by collagen, but the collagen-binding surface of GPVI is unknown. To address this issue we expressed, from insect cells, the immunoglobulin (Ig)–like ectodomains (residues 1-185) of human and murine GPVI, called hD1D2 and mD1D2, respectively. Both proteins bound specifically to collagen-related peptide (CRP), a GPVI-specific ligand, but hD1D2 bound CRP more strongly than did mD1D2. Molecular modeling and sequence comparison identified key differences between hD1D2 and mD1D2. Ten mutant hD1D2s were expressed, of which 4 had human residues replaced by their murine counterpart, and 6 had replacements by alanine. CRP binding studies with these mutants demonstrated that the exchange of lysine at position 59 for the corresponding murine glutamate substantially reduced binding to CRP. The position of lysine59 on the apical surface of GPVI suggests a mode of CRP binding analogous to that used by the related killer cell Ig-like receptors to bind HLA. This surface was confirmed as critical for collagen binding by epitope mapping of an inhibitory phage antibody against GPVI. This anti-GPVI, clone 10B12, gave dose-dependent inhibition of the hD1D2-collagen interaction. Clone 10B12 inhibited activation of platelets by CRP and collagen in aggregometry and thrombus formation by the latter in whole blood perfusion. Antibody 10B12 showed significantly reduced binding to the hD1D2-E59, and, on that basis, the GPVI:10B12 interface was modeled.

When sufficient insulin is administered to cause the sugar content of the blood to fall sharply to the vicinity of from 45 to 50 mg. per hundred cubic centimeters of blood, a severe reaction usually ensues. In animals, this reaction is accompanied by motor phenomena that are usually described as convulsions. Such convulsions are presumed to be the direct result of the existing hypoglycemia. Furthermore, various authors1 have found that, under electrical stimulus, irritability of the nerve increases when the blood sugar has been lowered with insulin. These facts raise the question whether persons who are subject to recurring convulsions show abnormal concentration of sugar in the blood.The observations so far reported are without much value because of the small number of patients examined. Thus, Heidema2 found hyperglycemia in two of five epileptic patients. Normal values were obtained by Kooy3 in eight patients and by Weston

Many physicians believe that defects of protein metabolism are of etiologic importance in epilepsy. This belief finds expression in the low protein diet which these clinicians prescribe for epileptic patients. The basis of such a belief is partly the result of therapeutic test and partly the result of laboratory experiment. Many writers have reported the beneficial effect of low protein, or of purin-free diets, though this favorable testimony is not unanimous. Cuneo,1 for example, states that improvement is more marked with a high protein than with a carbohydrate diet. Weeks2 et al. find no relation between diet and convulsions. The experimental evidence for faulty protein metabolism is found in the work of numerous investigators, mostly French, English and German, who have reported variations in the amounts of urinary uric acid, urea, ammonia or total nitrogen in the periods preceding or following convulsions. An analysis of these published data

Reports on the rejection of the Irish Supreme Court on an appeal brought by four home birth mothers against the State's refusal to provide them with community maternity services. View of the court on women's legal right to free maternity care; Provision of midwifery services at home; Efforts to access appropriate care for pregnant women.

Focuses on the policies in maternity care in Ireland. Integration of maternity care policies with the public health policies; Recognition of midwifery as separate profession from nursing and from obstetrics; Changes in national health and insurance systems privileging midwifery care.

The article examines the disadvantages of the Dutch-model UnFairCare health care policy being proposed by the Irish Fine Gael (FG). According to the article, the Dutch system is expensive and has cost implications for the average household. Contrary to the economies of scale being purported by FG, the Dutch experience shows the opposite to be the case and while the policy promises to abolish long term waits, the Dutch system shows growing list of wait listed patients.

In this study we demonstrate the suitability of the vertebrate Danio rerio(zebrafish) for functional screening of novel platelet genes in vivoby reverse genetics. Comparative transcript analysis of platelets and their precursor cell the megakaryocyte, together with nucleated blood cell elements, endothelial cells and erythroblasts, identified novel platelet membrane proteins with hitherto unknown role in thrombus formation. We determined the phenotype induced by antisense morpholino oligonucleotide (MO)-based knockdown of five of these genes in a laser-induced arterial thrombosis model. To validate the model, the genes for platelet Glycoprotein (GP) IIb and the coagulation protein Factor VIII were targeted. MO-injected fish showed normal thrombus initiation but severely impaired thrombus growth, consistent with the mouse knockout phenotypes, and concomitant knockdown of both resulted in spontaneous bleeding. Knockdown of four of the five novel platelet proteins altered arterial thrombosis, as demonstrated by modified kinetics of thrombus initiation and/or development. We identified a putative role for BAMBIand LRRC32in promotion and DCBLD2and ESAMin inhibition of thrombus formation. We conclude that phenotypic analysis of MO-injected zebrafish is a fast and powerful method for initial screening of novel platelet proteins for function in thrombosis.

In this study we demonstrate the suitability of the vertebrate Danio rerio (zebrafish) for functional screening of novel platelet genes in vivo by reverse genetics. Comparative transcript analysis of platelets and their precursor cell the megakaryocyte, together with nucleated blood cell elements, endothelial cells and erythroblasts, identified novel platelet membrane proteins with hitherto unknown role in thrombus formation. We determined the phenotype induced by antisense morpholino oligonucleotide (MO)-based knockdown of five of these genes in a laser-induced arterial thrombosis model. To validate the model, the genes for platelet Glycoprotein (GP) IIb and the coagulation protein Factor VIII were targeted. MO-injected fish showed normal thrombus initiation but severely impaired thrombus growth, consistent with the mouse knockout phenotypes, and concomitant knockdown of both resulted in spontaneous bleeding. Knockdown of four of the five novel platelet proteins altered arterial thrombosis, as demonstrated by modified kinetics of thrombus initiation and/or development. We identified a putative role for BAMBI and LRRC32 in promotion and DCBLD2 and ESAM in inhibition of thrombus formation. We conclude that phenotypic analysis of MO-injected zebrafish is a fast and powerful method for initial screening of novel platelet proteins for function in thrombosis.