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Background: Vitamin E (VE) bonded polysulfone dialysis membranes have putative erythropoiesis stimulating agent (ESA)-sparing and anti-inflammatory properties based on data from a small number of studies. We sought to investigate this in a large, prospective 12-month randomized controlled trial., Methods: Two-hundred and sixty prevalent haemodialysis (HD) patients were randomized to dialysis with VE-bonded polysulfone membranes or non-VE-bonded equivalents. All ESA-dosing was performed by means of a computer-based anaemia management decision support system. Monthly data were used to calculate the ESA resistance index (ERI) and blood tests were performed at baseline, 6 and 12 months for measurement of C-reactive protein (CRP) levels., Results: Of the 260 patients, 123 were randomized to dialysis with the VE-membrane and 12-month data was available for 220 patients. At the study population level, no beneficial effect of the VE membranes on the ERI or CRP levels was observed. Post hoc analyses indicated that there was a significant fall in ERI for patients with the highest baseline ESA resistance dialysed with the VE (9.28 [7.70-12.5] versus 7.70 [5.34-12.7] IU/week/kg/g/dL Hb, P = 0.01) but not the control membranes (9.45 [7.62-12.3] versus 8.14 [4.44-15.6] IU/week/kg/g/dL Hb, P = 0.41); this was not attributable to changes in CRP levels., Conclusions: Wholesale switching of all chronic HD patients to dialysis with VE-bonded polysulfone membranes appears not to be associated with improvements in ESA-responsiveness or CRP. These membranes may have utility in patients with heightened ESA resistance.

The global increase in obesity-induced type 2 diabetes (T2DM) represents a burden for healthcare systems worldwide. Of particular concern is the increased morbidity associated with T2DM, in particular cardiovascular disease (CVD), leading to premature death. Obesity initially leads to the development of insulin resistance in adipose and other tissues. Insulin resistance is initially compensated by increased insulin secretion but ultimately insufficient insulin is produced and this leads to the development of T2DM. Understanding the causal mechanisms underpinning the development of obesity-induced insulin resistance may be beneficial in improving quality of life and life expectancy, with the potential for a major global impact on healthcare systems. There is abundant evidence from animal, human studies and in vitro studies to support functional roles for a number of inflammatory factors in obesity-induced insulin resistance. In this review we provide an overview of the evidence supporting a fundamental role for the fluid phase (in particular the complement system) and the cellular components of the innate immune system in the pathogenesis of obesity-induced insulin resistance and ultimately development of T2DM., (Copyright © 2013 Elsevier GmbH. All rights reserved.)

Background: Endogenous arginine homologues, including homoarginine, have been identified as novel biomarkers for cardiovascular disease and outcomes. Our studies of human cohorts and a confirmatory murine model associated the arginine homologue homoarginine and its metabolism with stroke pathology and outcome., Methods and Results: Increasing homoarginine levels were independently associated with a reduction in all-cause mortality in patients with ischemic stroke (7.4 years of follow-up; hazard ratio for 1-SD homoarginine, 0.79 [95% confidence interval, 0.64-0.96]; P=0.019; n=389). Homoarginine was also independently associated with the National Institutes of Health Stroke Scale+age score and 30-day mortality after ischemic stroke (P<0.05; n=137). A genome-wide association study revealed that plasma homoarginine was strongly associated with single nucleotide polymorphisms in the L-arginine:glycine amidinotransferase (AGAT) gene (P<2.1 × 10(-8); n=2806), and increased AGAT expression in a cell model was associated with increased homoarginine. Next, we used 2 genetic murine models to investigate the link between plasma homoarginine and outcome after experimental ischemic stroke: (1) an AGAT deletion (AGAT(-/-)) and (2) a guanidinoacetate N-methyltransferase deletion (GAMT(-/-)) causing AGAT upregulation. As suggested by the genome-wide association study, homoarginine was absent in AGAT(-/-) mice and increased in GAMT(-/-) mice. Cerebral damage and neurological deficits in experimental stroke were increased in AGAT(-/-) mice and attenuated by homoarginine supplementation, whereas infarct size in GAMT(-/-) mice was decreased compared with controls., Conclusions: Low homoarginine appears to be related to poor outcome after ischemic stroke. Further validation in future trials may lead to therapeutic adjustments of homoarginine metabolism that alleviate stroke and other vascular disorders.

Background: People with Multiple Sclerosis (PwMS) are less physically active than the general population and pragmatic approaches designed to equip them with the skills and confidence to participate in long-term physical activity are required., Objective: The objective of this study was to determine the feasibility of a pragmatic exercise intervention in PwMS., Methods: A voluntary sample of 30 PwMS (male n = 4, female n = 26; mean age = 40 years; range = 24-49 years), with mild to moderate disability (EDSS ≤ 5.5), were recruited from eligible participants attending outpatient clinics. A total of 28 participants were randomised to a 10 week pragmatic exercise intervention (2× supervised and 1× home-based session per week) or usual care. Clinical, functional and quality of life (MSQoL-54) outcomes were assessed at baseline, immediately and 3 months after the intervention., Results: Attrition was low (2 participants lost to immediate follow-up and 4 participants lost to 3 month follow-up), with high compliance rates (>75% of all sessions). The intervention group achieved progression of exercise volume (24.3 ± 7.0 to 30.9 ± 5.5 min per session), intensity (60.4 ± 8.8 to 67.7 ± 6.9% HR max) and training impulse (min × average HR=training impulse/load [arbitrary units; AU]) (2600 ± 1105 to 3210 ± 1269AU) during the intervention, whilst significantly increasing(P = 0.050) their physical composite score (MSQOL-54) at 10 weeks and readiness to exercise (P = 0.003) at 3 months compared with usual care., Conclusion: This pragmatic intervention was feasible for PwMS, but further research is needed to assess its long-term impact on physical activity behaviour., (Copyright © 2013 Elsevier Inc. All rights reserved.)

Introduction: The Laotian rock rat is a relict species in a sister group relationship to hystricognath rodents (Hystricognathi). We asked whether there were similarities in placentation that might reflect this relationship or differences that might cast light on the evolution of Hystricognathi., Methods: We examined the reproductive tract of nonpregnant (n = 5), early (n = 3) and mid to late gestation (n = 2) females. Selected characters were mapped to a phylogenetic tree to examine their evolution in rodents., Results: The chorionic placenta was discoid and labyrinthine with a spongy zone but without internal lobes. The interhemal region was hemodichorial with syncytiotrophoblast lining maternal blood spaces and an inner layer of vacuolated cytotrophoblast. There was no subplacenta. The yolk sac was well developed with a villous portion that faced the placental disk but no fibrovascular ring. There was a single fetus that very likely would be precocial at birth., Discussion: A lobulated labyrinth and the presence of a subplacenta and a fibrovascular ring emerged as synapomorphies for Hystricognathi. Laonastes, Ctenodactylus and stem Hystricognathi all had precocial young, whereas altriciality was the plesiomorphic condition for rodents. A hemomonochorial interhemal region was plesiomorphic for rodents and Hystricognathi, and the hemodichorial condition found in Laonastes, and possibly in Ctenodactylus, was unlike that of any rodent studied to date., Conclusion: Similar to Hystricognathi, Laonastes bears precocial young, but this species lacks placental adaptations such as the subplacenta, suggesting they were evolved subsequent to a change in reproductive strategy in the common ancestor of Laonastes and Hystricognathi., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

The eutherian placenta is considered to possess great plasticity, but it is not clear how this variation reflects adaptation to different ecological niches. Because South America was isolated for most of the Tertiary, it represents a natural laboratory to examine this question. We here describe placentation in three South American groups: Xenarthra have been part of the fauna from at least the mid-Paleocene whereas caviomorph rodents and Neotropical primates are each derived from a single founder that reached South America in the Eocene and Oligocene, respectively. The common ancestor of Xenarthra had a villous, haemochorial placenta, from which the labyrinthine, endotheliochorial placenta of sloths later evolved. Placentation in Caviomorpha follows an extraordinary stable pattern, characterized by a haemomonochorial, labyrinthine and highly lobed structure with specialized growing areas. This pattern was present before arrival of these rodents in South America and enabled a successful radiation especially during the spread of grasslands. Neotropical primates have haemochorial, trabecular placentas with a specialized maternal blood supply; a pattern that contrasts with that of Old World monkeys and may have been present in the founder generation on arrival in South America. In conclusion, there is a dichotomy within Xenarthra but otherwise the ancient South American mammals do not show much variation in principal placental characters. Thus, the successful radiation of these three groups, and their adaptation to diverse ecological niches, did not require substantial alterations in placentation., (Copyright © 2013 Wiley Periodicals, Inc.)

The monomeric Rho GTPases are essential for cellular regulation including cell architecture and movement. A direct mechanism for hormonal regulation of the RhoA-type GTPases is their modulation by the G12 and G13 proteins via RH (RGS homology) containing RhoGEFs. In addition to the interaction of the G protein α subunits with the RH domain, activated RhoA also binds to the pleckstrin homology (PH) domain of PDZRhoGEF. The latter interaction is now extended to all seven members of the homologous Lbc family of RhoGEFs which includes the RH-RhoGEFs. This is evinced by direct measurements of binding or through effects on selected signaling pathways in cells. Overexpression of these PH domains alone can block RhoA-dependent signaling in cells to various extents. Whereas activated RhoA does not modulate the intrinsic activity of the RhoGEFs, activated RhoA associated with phospholipid vesicles can facilitate increased activity of soluble RhoGEFs on vesicle-delimited substrate (RhoA-GDP). This demonstrates feasibility of the hypothesis that binding of activated RhoA to the PH domains acts as a positive feedback mechanism. This is supported by cellular studies in which mutation of this binding site on PH strongly attenuates the stimulation of RhoA observed by overexpression of five of the RhoGEF DH-PH domains. This mutation is even more dramatic in the context of full-length p115RhoGEF. The utilization of this mechanism by multiple RhoGEFs suggests that this regulatory paradigm may be a common feature in the broader family of RhoGEFs.

FXIII (Factor XIII) is a Ca²+-dependent enzyme which forms covalent ϵ-(γ-glutamyl)lysine cross-links between the γ-carboxy-amine group of a glutamine residue and the ϵ-amino group of a lysine residue. FXIII was originally identified as a protein involved in fibrin clot stabilization; however, additional extracellular and intracellular roles for FXIII have been identified which influence thrombus resolution and tissue repair. The present review discusses the substrates of FXIIIa (activated FXIII) involved in thrombosis and wound healing with a particular focus on: (i) the influence of plasma FXIIIa on the formation of stable fibrin clots able to withstand mechanical and enzymatic breakdown through fibrin-fibrin cross-linking and cross-linking of fibrinolysis inhibitors, in particular α2-antiplasmin; (ii) the role of intracellular FXIIIa in clot retraction through cross-linking of platelet cytoskeleton proteins, including actin, myosin, filamin and vinculin; (iii) the role of intracellular FXIIIa in cross-linking the cytoplasmic tails of monocyte AT1Rs (angiotensin type 1 receptors) and potential effects on the development of atherosclerosis; and (iv) the role of FXIIIa on matrix deposition and tissue repair, including cross-linking of extracellular matrix proteins, such as fibronectin, collagen and von Willebrand factor, and the effects on matrix deposition and cell-matrix interactions. The review highlights the central role of FXIIIa in the regulation of thrombus stability, thrombus regulation, cell-matrix interactions and wound healing, which is supported by observations in FXIII-deficient humans and animals.

Epitheliochorial placentation is a derived condition and has evolved separately in strepsirrhine primates and laurasiatherians (pangolins, whales, and hoofed mammals). Usually it is associated with a long gestation period, small litters, and precocial young. Oxygen transfer is facilitated by indenting of the uterine and trophoblast epithelia by maternal and fetal capillaries, respectively. Histotrophic nutrition is important, and adaptations include areolas and hemophagous regions. In pigs and horses, for example, iron is transported as uteroferrin secreted from the uterine glands and taken up by areolas. In the horse, invasive trophoblast cells form cups within the endometrium that are the source of equine chorionic gonadotropin. In ruminants, binucleate trophoblast cells fuse with uterine epithelial cells to form trinucleate cells or plaques that secrete pregnancy hormones. There is evidence of immunosuppression in connection with these more invasive types of trophoblasts. The epitheliochorial condition may be advantageous for long pregnancies in large animals.

We conducted a genome-wide association study to identify novel associations between genetic variants and circulating plasminogen activator inhibitor-1 (PAI-1) concentration, and examined functional implications of variants and genes that were discovered. A discovery meta-analysis was performed in 19 599 subjects, followed by replication analysis of genome-wide significant (P < 5 × 10(-8)) single nucleotide polymorphisms (SNPs) in 10 796 independent samples. We further examined associations with type 2 diabetes and coronary artery disease, assessed the functional significance of the SNPs for gene expression in human tissues, and conducted RNA-silencing experiments for one novel association. We confirmed the association of the 4G/5G proxy SNP rs2227631 in the promoter region of SERPINE1 (7q22.1) and discovered genome-wide significant associations at 3 additional loci: chromosome 7q22.1 close to SERPINE1 (rs6976053, discovery P = 3.4 × 10(-10)); chromosome 11p15.2 within ARNTL (rs6486122, discovery P = 3.0 × 10(-8)); and chromosome 3p25.2 within PPARG (rs11128603, discovery P = 2.9 × 10(-8)). Replication was achieved for the 7q22.1 and 11p15.2 loci. There was nominal association with type 2 diabetes and coronary artery disease at ARNTL (P < .05). Functional studies identified MUC3 as a candidate gene for the second association signal on 7q22.1. In summary, SNPs in SERPINE1 and ARNTL and an SNP associated with the expression of MUC3 were robustly associated with circulating levels of PAI-1.

Placenta has a wide range of functions. Some are supported by novel genes that have evolved following gene duplication events while others require acquisition of gene expression by the trophoblast. Although not expressed in the placenta, high-affinity fetal hemoglobins play a key role in placental gas exchange. They evolved following duplications within the beta-globin gene family with convergent evolution occurring in ruminants and primates. In primates there was also an interesting rearrangement of a cassette of genes in relation to an upstream locus control region. Substrate transfer from mother to fetus is maintained by expression of classic sugar and amino acid transporters at the trophoblast microvillous and basal membranes. In contrast, placental peptide hormones have arisen largely by gene duplication, yielding for example chorionic gonadotropins from the luteinizing hormone gene and placental lactogens from the growth hormone and prolactin genes. There has been a remarkable degree of convergent evolution with placental lactogens emerging separately in the ruminant, rodent, and primate lineages and chorionic gonadotropins evolving separately in equids and higher primates. Finally, coevolution in the primate lineage of killer immunoglobulin-like receptors and human leukocyte antigens can be linked to the deep invasion of the uterus by trophoblast that is a characteristic feature of human placentation.

Objectives: To investigate the relationship among obesity, cardiovascular disease risk factors (CVDRFs), and plasma complement C3 concentration in children and adolescents., Methods: In a nationwide survey conducted between 1992 and 2000, all school children aged 6-18 yr with abnormal results in repeated urine samples, including hematuria, proteinuria, and glucosuria (n = 97 312; 36 557 boys and 60 755 girls), were investigated for their body mass index (BMI), blood pressure, fasting plasma glucose, total cholesterol, and plasma complement C3 concentrations., Results: Children in the higher percentile groups for BMI or having more CVDRFs, namely, hypertension, diabetes, and hypercholesterolemia, had higher plasma C3 concentrations independently (p for both trends <0.05, adjusted for age and gender). The odds ratios (ORs) for having one, two, or three CVDRFs in obese children were 4.74 [95% confidence interval (CI) = 4.47-5.03], 19.8 (95% CI = 17.8-22.0), and 139 (95% CI = 96.6-200), respectively, adjusted for age, gender, and family history of diabetes, which were substantially reduced after adjustment for plasma C3 concentrations. The ORs for children with plasma C3 concentrations in the highest quartile to have one, two, or three CVDRFs were 2.32 (95% CI = 2.21-2.44), 5.68 (95% CI = 4.83-6.67), and 58.6 (95% CI = 19.7-174), respectively, adjusted for age, gender, family history of diabetes, and BMI., Conclusion: Obesity is associated with clustering of CVDRFs in children and adolescents. Obesity and clustering of CVDRFs are associated with elevated plasma complement C3. Children and adolescents with higher plasma C3 concentrations have higher risk of clustering of CVDRFs independent of obesity., (© 2012 John Wiley & Sons A/S.)

Background and Method: Increased plasma clot density and prolonged lysis times are associated with cardiovascular disease. In this study, we employed a functional proteomics approach to identify novel clot components which may influence clot phenotypes., Results: Analysis of perfused, solubilised plasma clots identified inflammatory proteins, including complement C3, as novel clot components. Analysis of paired plasma and serum samples confirmed concentration-dependent incorporation of C3 into clots. Surface plasmon resonance indicated high-affinity binding interactions between C3 and fibrinogen and fibrin. Turbidimetric clotting and lysis assays indicated C3 impaired fibrinolysis in a concentration-dependent manner, both in vitro and ex vivo., Conclusion: These data indicate functional interactions between complement C3 and fibrin leading to prolonged fibrinolysis. These interactions are physiologically relevant in the context of protection following injury and suggest a mechanistic link between increased plasma C3 concentration and acute cardiovascular thrombotic events.

Endotheliochorial placentas occur in orders from all four major clades of eutherian mammal. Species with this type of placenta include one of the smallest (pygmy shrew) and largest (African elephant) land mammals. The endotheliochorial placenta as a definitive form has an interhemal area consisting of maternal endothelium, interstitial lamina, trophoblast, individual or conjoint basal laminas, and fetal endothelium. We commonly think of such placentas as having hypertrophied maternal endothelium with abundant rough endoplasmic reticulum (rER), and as having hemophagous regions. Considering them as a whole, the trophoblast may be syncytial or cellular, fenestrated or nonfenestrated, and there may or may not be hemophagous regions. Variations also appear in the extent of hypertrophy of the maternal endothelium and in the abundance of rER in these cells. This combination of traits and a few other features produces many morphological variants. In addition to endotheliochorial as a definitive condition, a transitory endotheliochorial condition may appear in the course of forming a hemochorial placenta. In some emballonurid bats the early endotheliochorial placenta has two layers of trophoblast, but the definitive placenta lacks an outer syncytial trophoblast layer. In mollosid bats a well developed endotheliochorial placenta is present for a short time even after a definitive hemochorial placenta has developed in a different region. It is concluded that the endotheliochorial placenta is more widespread and diversified than originally thought, with the variant with cellular trophoblast in particular appearing in several species studied recently., (Copyright © 2012. Published by Elsevier Ltd.)

Aims/hypothesis: Impaired fibrin clot lysis is a key abnormality in diabetes and complement C3 is one protein identified in blood clots. This work investigates the mechanistic pathways linking C3 and hypofibrinolysis in diabetes using ex vivo/in vitro studies., Methods: Fibrinolysis and C3 plasma levels were determined in type 1 diabetic patients and healthy controls, and the effects of glycaemia investigated. C3 incorporation into fibrin clots and modulation of fibrinolysis were analysed by ELISA, immunoblotting, turbidimetric assays and electron and confocal microscopy., Results: Clot lysis time was longer in diabetic children than in controls (599 ± 18 and 516 ± 12 s respectively; p < 0.01), C3 levels were higher in diabetic children (0.55 ± 0.02 and 0.43 ± 0.02 g/l respectively; p < 0.01) and both were affected by improving glycaemia. An interaction between C3 and fibrin was confirmed by the presence of lower protein levels in sera compared with corresponding plasma and C3 detection in plasma clots by immunoblot. In a purified system, C3 was associated with thinner fibrin fibres and more prolongation of lysis time of clots made from fibrinogen from diabetic participants compared with controls (244 ± 64 and 92 ± 23 s respectively; p < 0.05). Confocal microscopy showed higher C3 incorporation into diabetic clots compared with controls, and fully formed clot lysis was prolonged by 764 ± 76 and 428 ± 105 s respectively (p < 0.05). Differences in lysis, comparing diabetes and controls, were not related to altered plasmin generation or C3-fibrinogen binding assessed by plasmon resonance., Conclusions/interpretation: C3 incorporation into clots from diabetic fibrinogen is enhanced and adversely affects fibrinolysis. This may be one novel mechanism for compromised clot lysis in diabetes, potentially offering a new therapeutic target.

Objective: Emerging data implicate activation of the complement cascade in the pathogenesis of type 2 diabetes. The objective of the current study was to evaluate the relationships between components of the complement system, metabolic risk factors, and family history of type 2 diabetes in healthy South Asians., Research Design and Methods: We recruited 119 healthy, first-degree relatives of South Asian subjects with type 2 diabetes (SARs) and 119 age- and sex-matched, healthy South Asian control subjects (SACs). Fasting blood samples were taken for measurement of complement factors and standard metabolic risk factors., Results: SARs were characterized by significantly higher properdin (mean concentration 12.6 [95% CI 12.2-13.1] mg/L vs. SACs 10.1 [9.7-10.5] mg/L, P < 0.0001), factor B (187.4 [180.1-195.0] mg/L vs. SACs 165.0 [158.0-172.2] mg/L, P < 0.0001), and SC5b-9 (92.0 [86.1-98.3] ng/mL vs. SACs 75.3 [71.9-78.9] ng/mL, P < 0.0001) and increased homeostasis model assessment of insulin resistance (2.86 [2.61-3.13] vs. SACs 2.31 [2.05-2.61], P = 0.007). C-reactive protein did not differ between SARs and SACs (P = 0.17). In subgroup analysis of 25 SARs and 25 SACs with normal oral glucose tolerance tests, properdin, factor B, and SC5b-9 remained significantly elevated in SARs., Conclusions: Increased properdin and complement activation are associated with a family history of type 2 diabetes in South Asians independent of insulin resistance, and predate the development of impaired fasting glucose and impaired glucose tolerance. Properdin and SC5b-9 may be novel biomarkers for future risk of type 2 diabetes in this high-risk population and warrant further investigation.

The way in which maternal blood is associated with trophoblast prior to the formation of the different types of hemochorial placenta may be conveniently grouped into four main patterns: a transitory endotheliochorial condition; maternal blood released into a mass of trophoblast; maternal blood confined to lacunae; and fetal villi entering preexisting maternal blood sinuses. Although it might be considered logical that developing placentas would pass through an endotheliochorial stage to become hemochorial, this developmental pattern is seen only as a transient stage in several species of bats and sciuromorph rodents. More commonly a mass of trophoblast at the junction with the endometrium serves as a meshwork through which maternal blood passes, with subsequent organization of a labyrinth when the fetal vascular component is organized. The initial trophoblast meshwork may be cellular or syncytial, often leading to a similar relationship in the spongy zone and labyrinth. Old World monkeys, apes and humans have a lacunar stage prior to establishing a villous hemochorial condition. New World monkeys lack a true lacunar stage, retaining portions of maternal vessels for some time and initially forming a trabecular arrangement similar to though differently arrived at than that in the tarsier. In armadillos, preexisting maternal venous sinuses are converted into an intervillous blood space by intruding fetal villi. Variations from the major patterns of development also occur. The way in which the definitive placental form is achieved developmentally should be considered when using placental structure to extrapolate evolution of placentation., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

A wealth of evidence indicates a fundamental role for inflammation in the pathogenesis of cardiovascular disease (CVD), contributing to the development and progression of atherosclerotic lesion formation, plaque rupture, and thrombosis. An increasing body of evidence supports a functional role for complement activation in the pathogenesis of CVD through pleiotropic effects on endothelial and haematopoietic cell function and haemostasis. Prospective and case control studies have reported strong relationships between several complement components and cardiovascular outcomes, and in vitro studies and animal models support a functional effect. Complement activation, in particular, generation of C5a and C5b-9, influences many processes involved in the development and progression of atherosclerosis, including promotion of endothelial cell activation, leukocyte infiltration into the extracellular matrix, stimulation of cytokine release from vascular smooth muscle cells, and promotion of plaque rupture. Complement activation also influences thrombosis, involving components of the mannose-binding lectin pathway, and C5b-9 in particular, through activation of platelets, promotion of fibrin formation, and impairment of fibrinolysis. The participation of the complement system in inflammation and thrombosis is consistent with the physiological role of the complement system as a rapid effector system conferring protection following vessel injury. However, in the context of CVD, these same processes contribute to development of atherosclerosis, plaque rupture, and thrombosis.

Angiotensin I-converting enzyme inhibitors (ACEi) are widely used antihypertensive agents that are associated with a potentially life-threatening reaction, ACEi-angioedema. Impaired metabolism of bradykinin and des-Arg(9) -bradykinin by aminopeptidase P (APP) is a key contributor to ACEi-angioedema. This study aimed to characterize the genetic regulation of the XPNPEP2 gene and identify the genetic factors contributing to variance in plasma APP activity and ACEi-angioedema. Additive genetic factors accounted for 47.3% of variance in plasma APP activity in healthy individuals. Nested deletion analysis identified the minimal promoter (-338 bp to -147 bp) and an enhancer region (-2,502 bp to -2,238 bp). Three polymorphisms (c.-2399C>A, c.-1612G>T, and c.-393G>A) were significantly associated with plasma APP activity. Haplotype ATG was significantly associated with reduced reporter gene activity and with reduced plasma APP activity. The c.-2399C>A polymorphism was located in an enhancer region and was predicted to differentially bind hepatic nuclear factor 4 (HNF4). Over expression of HNF4 increased the activation of haplotype ATG compared with haplotype CGG. In a case control study of subjects with a history of ACEi-angioedema, haplotype ATG was significantly associated with ACEi-angioedema (OR 4.87 [1.78-13.35] P = 0.002). The ATG haplotype is functional and contributes to ACEi-angioedema through a reduction in APP., (© 2011 Wiley Periodicals, Inc.)

Objective: Neprilysin (NEP), a zinc metalloendopeptidase, has a role in blood pressure control and lipid metabolism. The present study tested the hypothesis that NEP is associated with insulin resistance and features of the metabolic syndrome (MetS) in a study of 318 healthy human subjects and in murine obesity, and investigated NEP production by adipocytes in-vitro., Methods and Results: In 318 white European males, plasma NEP was elevated in the MetS and increased progressively with increasing MetS components. Plasma NEP activity correlated with insulin, homoeostasis model assessment and body mass index (BMI) in all subjects (P<0.01). Quantitative reverse transcriptase PCR (RT-PCR) and western blotting showed that in human pre-adipocytes NEP expression is upregulated 25- to 30-fold during differentiation into adipocytes. Microarray analysis of mRNA from differentiated human adipocytes confirmed high-NEP expression comparable with adiponectin and plasminogen activator inhibitor-1. In a murine model of diet-induced insulin resistance, plasma NEP levels were significantly higher in high-fat diet (HFD)-fed compared with normal chow diet (NCD)-fed animals (1642 ± 529 and 820 ± 487 pg μl(-1), respectively; P<0.01). Tissue NEP was increased in mesenteric fat in HFD compared with NCD-fed mice (P<0.05). NEP knockout mice did not display any changes in insulin resistance, glucose tolerance, or body and epididymal fat pad weight compared with wild-type mice., Conclusion: In humans, NEP activity correlated with BMI and measures of insulin resistance with increasing levels in subjects with multiple cardiovascular risk factors. NEP protein production in human adipocytes increased during cell differentiation and plasma and adipose tissue levels of NEP were increased in obese insulin-resistant mice. Our results indicate that NEP associates with cardiometabolic risk in the presence of insulin resistance and increases with obesity.

In contrast to baboon or rhesus macaque, trophoblast invasion in the human placental bed occurs by the interstitial as well as the endovascular route and reaches as deep as the inner myometrium. We here describe two rare specimens of gorilla placenta. In the light of recent findings in the chimpanzee, we postulated the occurrence of deep invasion in gorilla pregnancy. Tissues were processed for histology (PAS, orcein), lectin staining (Ulex europaeus agglutinin 1) and immunohistochemistry (cytokeratin 7/17, α-actin). A specimen of young but undetermined gestational age included deep placental bed tissue, showing interstitial and spiral artery invasion of the inner myometrium as well as the decidua. The cell density and depth of trophoblast invasion was equivalent to a human placental bed of 10-14 weeks. Intraluminal trophoblasts were not seen in any of the invaded vessels, allowing no definite conclusions about the origin of the intramural trophoblast and the time-course of spiral artery invasion. A different late second trimester placenta specimen showed scattered extravillous trophoblast in the basal plate and underlying decidua, as well as a remodelled spiral artery containing intramural trophoblast. Absence of inner myometrial tissue precluded assessment of invasion depth in this later specimen. Despite the limited material we can conclude that key aspects of trophoblast invasion are shared by the three hominid species: gorilla, chimpanzee and human., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

Alpha-2-antiplasmin (α2AP) undergoes both N- and C-terminal cleavages, which significantly modify its activities. Compared with other Ser protease inhibitors (serpins), α2AP contains an ~50-residue-extended C-terminus, which binds plasmin(ogen). We developed 2 new ELISAs to measure the antigen levels of free total α2AP and free C-terminally intact α2AP to investigate whether α2AP antigen levels or α2AP C-terminal cleavage were associated with myocardial infarction (MI) in 320 male MI survivors and 169 age-matched controls. Patients had 15.2% reduced total α2AP antigen levels compared with controls (93.8 vs 110.6 U/dL, P < .001), with a 10.1-fold (95% confidence interval [CI]: 5.5-18.9) increased MI risk for levels in the 1st quartile compared with the 4th quartile. The percentage of C-terminal cleavage did not differ between patients and controls (38.7% and 38.1%, respectively, P = .44). In addition, all individuals were genotyped for the polymorphism Arg407Lys, which is located near the start of the extended C-terminus. Arg407Lys was not associated with α2AP C-terminal cleavage, total α2AP antigen levels, or MI risk (odds ratios compared with Arg/Arg: Arg/Lys 0.74, 95% CI: 0.50-1.10; Lys/Lys 0.77, 95% CI: 0.31-1.92). Our data show that levels of free full-length α2AP were decreased in MI, that the percentage of C-terminally cleaved α2AP was unaltered, and that Arg407Lys did not influence α2AP levels or MI risk.

It is now possible to view human placentation in an evolutionary context because advances in molecular phylogenetics provide a reliable scenario for the evolution of mammals. Perhaps the most striking finding is the uniqueness of human placenta. The lower primates have non-invasive placentae and even tarsiers and New World monkeys show restricted trophoblast invasion. Moreover, a truly villous placenta occurs only in Old World monkeys and great apes. The two latter groups of haplorhine primates show varying degrees of trophoblast-uterine interaction, including differences in the extent of decidualization, formation and disintegration of a cytotrophoblastic shell, degree of interstitial trophoblast invasion and depth of trophoblast invasion into spiral arteries. Recently, the occurrence of human-like deep invasion was confirmed in gorillas and chimpanzees. As the still enigmatic disease of pre-eclampsia also occurs in these species, such information may reveal the evolutionary roots of this disease of impaired maternal-fetal interaction., (Copyright © 2010 Elsevier Ltd. All rights reserved.)

Deep trophoblast invasion is usually considered to be a unique feature of human placentation as compared to other primates. Because of the occasional occurrence of preeclampsia in great apes, which in the human is associated with impaired deep invasion, this uniqueness may be questioned. The availability of two well-documented pregnant chimpanzee uteri in the Hubrecht Collection (Museum für Naturkunde, Berlin) allowed us to evaluate the extent of trophoblast invasion in this species. By adjusting currently used protocols, we obtained successful immunohistochemical staining for cytokeratin and α-actin, as well as Ulex europaeus agglutinin 1 (UEA1) lectin staining, in this archival material. In both specimens interstitial trophoblast invasion had occurred in both decidua and myometrium. Because of a lack of published data on fetal growth for this species, fetal sizes (7cm and 13cm) could not be strictly related to gestational ages and thus be compared with the time-course of human trophoblast invasion. However, since the earlier specimen did not show any endovascular trophoblast invasion in spiral arteries - in contrast to pregnant human uteri with equivalent fetal sizes - endovascular migration seems to begin at a different gestational age in the chimpanzee. In the later specimen endovascular trophoblast was associated with spiral artery remodelling in the inner myometrium, and this invasion was extended to include a radial artery, which at that stage still showed relatively intact vascular smooth muscle and elastic lamina. We conclude that invasion depth and spiral artery remodelling are basically similar in chimpanzees and humans, although the seemingly different time of onset may have implications for uteroplacental oxygen supply and fetal development., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

Background: Sigmodontinae, known as "New World rats and mice," is a large subfamily of Cricetidae for which we herein provide the first comprehensive investigation of the placenta., Methods: Placentas of various gestational ages ranging from early pregnancy to near term were obtained for five genera, i.e. Necromys, Euryoryzomys, Cerradomys, Hylaeamys, and Oligoryzomys. They were investigated by means of histology, immunohistochemistry, a proliferation marker, DBA-lectin staining and transmission electron microscopy., Results: The chorioallantoic placenta was organized in a labyrinthine zone, spongy zone and decidua and an inverted yolk sac persisted until term. The chorioallantoic placenta was hemotrichorial. The interhemal barrier comprised fetal capillary endothelium and three layers of trophoblast, an outermost, cellular layer and two syncytial ones, with interspersed trophoblast giant cells (TGC). In addition, accumulations of TGC occurred below Reichert's membrane. The junctional zone contained syncytial trophoblast, proliferative cellular trophoblast, glycogen cells and TGC that were situated near to the maternal blood channels. In three of the genera, TGC were also accumulated in distinct areas at the placental periphery. PAS-positive glycogen cells derived from the junctional zone invaded the decidua. Abundant maternal uNK cells with positive response to PAS, vimentin and DBA-lectin were found in the decidua. The visceral yolk sac was completely inverted and villous., Conclusion: The general aspect of the fetal membranes in Sigmodontinae resembled that found in other cricetid rodents. Compared to murid rodents there were larger numbers of giant cells and in some genera these were seen to congregate at the periphery of the placental disk. Glycogen cells were found to invade the decidua but we did not identify trophoblast in the walls of the deeper decidual arteries. In contrast these vessels were surrounded by large numbers of uNK cells. This survey of wild-trapped specimens from five genera is a useful starting point for the study of placentation in an important subfamily of South American rodents. We note, however, that some of these rodents can be captive bred and recommend that future studies focus on the study of time dated pregnancies.

Deep trophoblast invasion in the placental bed has been considered the hallmark of human pregnancy. It occurs by two routes, interstitial and endovascular, and results in transformation of the walls of the spiral arteries as they traverse the decidua and the inner third of the myometrium. Disturbances in this process are associated with reproductive disorders such preeclampsia. In contrast, trophoblast invasion in Old World monkeys occurs only by the endovascular route and seldom reaches the myometrium. Recently, it was shown that this pattern is maintained in gibbons, but that the human arrangement also occurs in chimpanzee and gorilla. There is an interesting parallel with results from placental immunology regarding the evolution of the major histocompatability complex class I antigen HLA-C and its cognate receptors. HLA-C is not present in Old World monkeys or gibbons. It emerged in the orangutan and became polymorphic in the lineage leading to gorilla, bonobo, chimpanzee, and human. Interaction between HLA-C1 and HLA-C2 on the surface of trophoblast and killer immunoglobulin-like receptors (KIRs) expressed by uterine natural killer cells are important regulators of trophoblast invasion. Evolution of this system in great apes may have been one prerequisite for deep trophoblast invasion but seems to have come at a price. The evidence now suggests that certain combinations of maternal genotype for KIRs and fetal genotype for HLA-C imply an increased risk of preeclampsia, fetal growth restriction, and recurrent abortion. The fetal genotype is in part derived from the father providing an explanation for the paternal contribution to reproductive disorders.

A century ago Thomas G. Lee amassed an unparalleled collection of developmental series of North American rodents such as the thirteen-lined ground squirrel, the Plains pocket gopher and Merriam's kangaroo rat. He was the first to describe the initial attachment of the squirrel blastocyst to the antimesometrial side of the uterus. The full potential of Lee's material was not realized until after his death, when it came into the possession of Mossman. The latter relied heavily on Lee's collection when writing his seminal monograph on the comparative morphogenesis of fetal membranes and much of Lee's material was subsequently described in detail by Mossman and others. It now forms part of the Harland W. Mossman Collection at the University of Wisconsin., (Copyright © 2010 Elsevier Ltd. All rights reserved.)

Hans Strahl, a contemporary of Duval and Hubrecht, made many important contributions to comparative placentation. Despite this he is not well known and some of his original observations tend to be attributed to later authors. Strahl published a classification of placental types based on their shape and relationship to maternal tissues. This greatly influenced the work of Otto Grosser, who became better known in part because his work was more accessible to other scientists and clinicians. Strahl described the development of the fetal membranes across a broad range of mammalian orders extending his observations beyond parturition to the post partum involution of the uterus. He paid close attention to structures designed for histotrophic nutrition including the areolae of moles, haemophagous organs of carnivores and tenrecs and chorionic vesicles of lemurs and lorises. We here provide a summary of some of the most important findings made by Strahl including work on placentation in carnivores and higher primates that remains unsurpassed., (Copyright © 2010 Elsevier Ltd. All rights reserved.)

Objective: To identify novel polymorphisms in the genes encoding the transcription factors CCAAT/enhancer binding protein alpha, beta and delta ( CEBPA, CEBPB, CEBPD) and investigate associations between polymorphisms and obesity-related phenotypes., Methods: Denaturing high-performance liquid chromatography (HPLC) was used to screen for novel gene variants and polymorphisms were genotyped in stored DNA from participants of the Leeds Family Study (537 subjects from 89 families). Genotype and haplotype analyses were carried out in STATA and PBAT, respectively., Results: Twenty-five polymorphisms were identified; 11 in CEBPA, 12 in CEBPB and 2 in CEBPD. Several allelic variants were associated at a nominal 5% level with waist-to-hip ratio (-919G>A in CEBPA, -412G>T and 646C>T in CEBPB), leptin (1558G>A in CEBPA, -1051A>G and 1383T>- in CEBPB) and adiponectin (1382G>T and 1903G>T in CEBPB). Effects of CEBPA and CEBPB allelic variants were independent, but variants within each gene were in linkage disequilibrium. Several associations were observed between other obesity-related traits and allelic variants in CEBPA and CEBPB, but not CEBPD., Conclusion: These findings suggest that common allelic variants in CEBPA and CEBPB could influence abdominal obesity and related metabolic abnormalities associated with type 2 diabetes and cardiovascular disease in healthy White Northern European families, although results require independent confirmation.

The adenomatous polyposis coli (APC) gene product is mutated in the vast majority of human colorectal cancers. APC negatively regulates the WNT pathway by aiding in the degradation of beta-catenin, which is the transcription factor activated downstream of WNT signaling. APC mutations result in beta-catenin stabilization and constitutive WNT pathway activation, leading to aberrant cellular proliferation. APC mutations associated with colorectal cancer commonly fall in a region of the gene termed the mutation cluster region and result in expression of an N-terminal fragment of the APC protein. Biochemical and molecular studies have revealed localization of APC/Apc to different sub-cellular compartments and various proteins outside of the WNT pathway that associate with truncated APC/Apc. These observations and genotype-phenotype correlations have led to the suggestion that truncated APC bears neomorphic and/or dominant-negative function that support tumor development. To analyze this possibility, we have generated a novel allele of Apc in the mouse that yields complete loss of Apc protein. Our studies reveal that whole-gene deletion of Apc results in more rapid tumor development than the APC multiple intestinal neoplasia (Apc(Min)) truncation. Furthermore, we found that adenomas bearing truncated Apc had increased beta-catenin activity when compared with tumors lacking Apc protein, which could lead to context-dependent inhibition of tumorigenesis.

Objective: Methylarginines have been shown to interfere with nitric oxide (NO) formation by inhibiting NO synthase (asymmetric dimethylarginine, ADMA, and monomethylarginine, NMMA) and the cellular l-arginine uptake system (ADMA, NMMA and symmetric dimethylarginine, SDMA), thereby causing endothelial dysfunction. ADMA is a predictor of cardiovascular events and mortality in diverse populations., Methods: We investigated whether methylarginines are predictors of mortality in 394 patients after acute ischemic stroke during 7.4 years of follow-up., Results: Patients who died (N=231) were older and more frequently had one of the traditional risk factors for stroke (previous stroke/TIA, atrial fibrillation, prevalent ischemic heart disease, peripheral vascular disease, each p<0.05). ADMA (0.52 micromol/l vs. 0.50 micromol/l, p=0.015) and SDMA (0.56 micromol/l vs. 0.43 micromol/l, p<0.001) were higher in patients who died. In multivariable-adjusted hazard models, SDMA but not ADMA or NMMA was an independent predictor of all-cause mortality after stroke (SDMA, hazard ratio 2.41 (1.55-3.72), p<0.001; ADMA, hazard ratio 1.43 (0.99-2.07), p=0.06). SDMA was significantly associated with atrial fibrillation (0.55 micromol/l vs. 0.50 micromol/l, p=0.03) but there was no significant interaction between SDMA and AF in relation to mortality (p=0.81). SDMA remained significantly associated with mortality after adjusting for eGFR and also additionally adjusting for C-reactive protein, albumin, beta-thromboglobulin, and von Willebrand factor., Conclusion: Our study demonstrates that SDMA is an independent predictor of total mortality after acute stroke irrespective of renal function. SDMA is associated with atrial fibrillation, endothelial and platelet activation, and may therefore play a previously unknown role in the pathophysiology of stroke., (Copyright 2009 Elsevier Ireland Ltd. All rights reserved.)

Interest in insectivoran grade mammals has been reawakened by taxonomic changes that place tenrecs and golden moles in a new order and separate hedgehogs from moles, shrews and solenodons. This survey of their placentation shows there is great variation even within families. As an example three subfamilies of tenrec have been examined. The interhemal region is cellular hemomonochorial in Echinops and Microgale but endotheliochorial in Micropotamogale. Golden moles, which are placed in the same order, have hemodichorial placentation. Many insectivores have complex arrangements for histotrophic nutrition involving columnar trophoblast cells. These range from areolae in moles through complexly folded hemophagous regions in tenrecs to the trophoblastic annulus in shrews. Of these placental characters, few offer support to current phylogenies. However, the case for placing hedgehogs and gymnures in a separate order (Erinaceomorpha) is bolstered by the presence of interstitial implantation, amniogenesis by cavitation, a hemochorial barrier and a prominent spongy zone; these features do not occur in shrews, moles or solenodons (Soricomorpha). Three insectivoran grade mammals deserve close attention as they have been selected for genome sequencing. One of these, the European hedgehog (Erinaceus europaeus), has not been studied with current methodology and renewed investigation of this or the closely related genus Atelerix should be a priority.

Arterial thrombosis is a pivotal event in the development of cardiovascular diseases. Plasma and cellular proteins have the potential to influence thrombus morphology and function. This review summarizes the latest studies to use proteomic technologies to characterize the cellular and plasma components involved in arterial thrombosis, with a view to understanding the pathogenesis and treatment of acute cardiovascular diseases. Proteomic approaches have been extensively used to profile the proteome of endothelial cells, leukocytes, vascular smooth muscle cells, platelets and plasma in the search for risk factors for cardiovascular disease; however, further work is required to validate the direct contribution of these proteins to arterial thrombosis.

A recent phylogenetic analysis achieved good resolution between the 5 suborders of rodent. As a novel finding it suggested a basal split that gave rise to a monophyletic group comprising Hystricomorpha and Sciuromorpha. We asked whether the new tree could cast light on the evolution of the interhaemal barrier in rodents where at least seven variants have been described. To supplement existing data we first examined the placenta of the common gundi, Ctenodactylus gundi. It was shown to be haemochorial with a single layer of syncytiotrophoblast in the interhaemal membrane but with nests of cytotrophoblast elsewhere. Next we used character mapping on the recent tree to determine the pattern of evolution of the placenta with respect to principal type (e.g. haemochorial) and the trophoblast found within the interhaemal barrier. This indicated that the common ancestor of living rodents had a haemochorial placenta and that there were two independent transformations to the endotheliochorial type. Moreover, the interhaemal barrier was found to have had a single layer of syncytial trophoblast in the common ancestor of rodents, a condition that was retained in the clade comprising Hystricomorpha and Sciuromorpha. In contrast the second clade shows multiple character transformations.

Bats are a highly successful, widely distributed group, with considerable variation in placental structure. The Egyptian slit-faced bat Nycteris thebaica is a member of one of the few families with previously undescribed placentation. It was found that, although the interhemal type of the Nycteris placenta is endotheliochorial with a single layer of cytotrophoblast, the arborizing pattern of the maternal vessels and especially the extraordinary major placental artery differs from the placenta of the emballonurid bats to which this family is considered to be most closely related. The major placental artery providing maternal blood to the vessels of the placental disk has a highly glycosylated matrix surrounded by two-layered folds of trophoblast, forming an apparently rigid structure of unique morphology. The yolk sac is collapsed, with hypertrophied endodermal and mesothelial cells similar to many other bat species. The paraplacenta is extensive with abundant fetal vessels underlying cytotrophoblast and syncytial trophoblast layers, fronting on an endometrium that largely lacks uterine epithelial cells but has large decidual cells and is poorly vascularized. The placenta of Nycteris lacks a hemophagous region, unlike the emballonurid bats Taphozous and Saccopteryx. Although the latter two species have similar placentas, the placental structure of Nycteris does little to relate it to the other family within the Emballonuroidea. Shared and divergent reproductive characters are discussed in relationship to bat phylogenetic relationships.

The development of occlusive arterial and venous disease is contingent on the formation of a fibrin mesh that occurs following tissue damage and activation of the coagulation system. Clinical evidence indicates that fibrin structure and function are important determinants of cardiovascular risk, and the difference between clots formed from plasma and from purified fibrinogen highlights the importance of plasma factors in determining final clot structure. Twin, family, and case-control studies indicate there is a significant genetic contribution to variance in coagulation and fibrinolytic factors that may influence clot structure. Additionally, studies indicate a smaller but significant genetic contribution to fibrin structure, with a larger component provided by the environmental contribution. Future studies of the influence of post-translational modifications to fibrin(ogen) and other factors involved in clot formation may provide important insights into thrombotic disease mechanisms., (Copyright Thieme Medical Publishers.)

The placentation of the Hottentot golden mole (Amblysomus hottentotus) has been examined using light and electron microscopy and lectin histochemistry of nine specimens at both mid and late gestation. The placentae were lobulated towards the allantoic surface and the lobules contained roughly parallel arrays of labyrinthine structures converging on a central spongy zone. At mid gestation, the arrays were composed of an inner cellular and outer syncytial trophoblast layer, the inner layer enclosing scant connective tissue and fetal capillaries. Maternal blood spaces coursed through the outer trophoblast and were lined by trophoblastic microvilli; the blood spaces were narrow in mid gestation but enlarged near term, while the inner trophoblast layer became thinner and seemed to be syncytial. These features were confirmed by transmission electron microscopy. The microvillous surfaces and dispersed cytoplasmic particles were heavily glycosylated, as shown by lectin histochemistry, and exhibited changes with maturation, particularly a loss in N-acetyl glucosamine oligomers bound by Phytolacca americana lectin on the microvilli lining the maternal blood spaces and outer trophoblast particles. A substantial yolk sac was present both in mid and late gestation stages. It was clearly unattached to the uterus in the later stages. These morphological features are discussed in relation to the phylogenetic position of Amblysomus with respect to other members of Afrosoricida and Afrotheria.

Background: The guinea pig is an attractive model for human pregnancy and placentation, mainly because of its haemomonochorial placental type, but is rather small in size. Therefore, to better understand the impact of body mass, we studied placental development in the capybara which has a body mass around 50 kg and a gestation period of around 150 days. We paid attention to the development of the lobulated arrangement of the placenta, the growth of the labyrinth in the course of gestation, the differentiation of the subplacenta, and the pattern of invasion by extraplacental trophoblast., Methods: Material was collected from six animals at pregnancy stages ranging from the late limb bud stage to mid gestation. Methods included latex casts, standard histology, immunohistochemistry for cytokeratin, vimentin, alpha-smooth muscle actin, and proliferating cell nuclear antigen as well as transmission electron microscopy., Results: At the limb bud stage, the placenta was a pad of trophoblast covered by a layer of mesoderm from which fetal vessels were beginning to penetrate at folds in the surface. By 70 days, the placenta comprised areas of labyrinth (lobes) separated by interlobular areas. Placental growth resulted predominantly from proliferation of cellular trophoblast situated in nests at the fetal side of the placenta and along internally directed projections on fetal mesenchyme. Additional proliferation was demonstrated for cellular trophoblast within the labyrinth.Already at the limb bud stage, there was a prominent subplacenta comprising cellular and syncytial trophoblast with mesenchyme and associated blood vessels. At 90 days, differentiation was complete and similar to that seen in other hystricognath rodents. Overlap of fetal vessels and maternal blood lacunae was confirmed by latex injection of the vessels. At all stages extraplacental trophoblast was associated with the maternal arterial supply and consisted of cellular trophoblast and syncytial streamers derived from the subplacenta., Conclusion: All important characteristics of placental development and organization in the capybara resembled those found in smaller hystricognath rodents including the guinea pig. These features apparently do not dependent on body size. Clearly, placentation in hystricognaths adheres to an extraordinarily stable pattern suggesting they can be used interchangeably as models of human placenta.

Objective: Fibrin makes up the structural basis of an occlusive arterial thrombus, and variability in fibrin phenotype relates to cardiovascular risk. The aims of the current study from the EU consortium EuroCLOT were to (1) determine the heritability of fibrin phenotypes and (2) identify QTLs associated with fibrin phenotypes., Methods and Results: 447 dizygotic (DZ) and 460 monozygotic (MZ) pairs of healthy UK white female twins and 199 DZ twin pairs from Denmark were studied. D-dimer, an indicator of fibrin turnover, was measured by ELISA and measures of clot formation, morphology, and lysis were determined by turbidimetric assays. Heritability estimates and genome-wide linkage analysis were performed. Estimates of heritability for d-dimer and turbidometric variables were in the range 17% to 46%, with highest levels for maximal absorbance which provides an estimate of clot density. Genome-wide linkage analysis revealed 6 significant regions with LOD >3 on 5 chromosomes (5, 6, 9, 16, and 17)., Conclusions: The results indicate a significant genetic contribution to variability in fibrin phenotypes and highlight regions in the human genome which warrant further investigation in relation to ischemic cardiovascular disorders and their therapy.

Background: Inflammatory processes play a fundamental role in the development of cardiovascular disease., Objectives: To compare the associations of complement C3 and C-reactive protein (CRP) with myocardial infarction (MI) and cardiovascular risk factors., Methods: 342 Caucasian male subjects aged < or =65 years with MI and 193 Caucasian age matched healthy male control subjects were recruited. C3 and CRP were measured by ELISA., Results: C3 and CRP were significantly higher (p<0.001) in patients compared with healthy subjects (patients vs. healthy subjects, C3: 1.22gL(-1) vs. 1.00gL(-1); CRP: 1.41mgL(-1) vs. 0.72mgL(-1)). In a logistic regression model, including conventional cardiovascular risk factors, C3 was independently associated with MI (odds ratio for a 1 S.D. increase in C3: 2.29 [1.58, 2.92]); and this association remained after including CRP and/or fibrinogen in the model. CRP was independently associated with MI after accounting for conventional risk factors (odds ratio for a 1 S.D. increase in CRP: 1.47 [1.16, 1.87]), however, this association was lost when C3and/or fibrinogen were included in the model. Receiver operating characteristic (ROC) analysis indicated that the model which best predicted MI was the model including C3 and fibrinogen., Conclusions: These data suggest that elevated C3 is independently associated with MI and that elevated C3 may be a more specific marker of the inflammatory processes underpinning MI than CRP.

A review is given of the factors determining placental oxygen transfer and the oxygen supply to the fetus. In the case of continuous variables, such as the rate of placental blood flow, it is not possible to trace evolutionary trends. Discontinuous variables, for which we can define character states, are more amenable to analysis. This is exemplified by factors contributing, respectively, to blood oxygen affinity and placental diffusing capacity. Comparative genomics has given fresh insight into the evolution of the beta-globin gene complex. In higher primates, duplication of an embryonic gene yielded HBG-T2, a gene that is expressed in the fetus and confers high oxygen affinity on its haemoglobin. A separate event in ruminants involved duplication of an adult gene, again resulting in a fetally expressed variant (HBB-T3) that conveys high oxygen affinity. In rodents and lagomorphs, where fetal and adult haemoglobin are not different, developmental regulation of 2, 3-diphosphoglycerate ensures the high oxygen affinity of fetal blood. Oxygen diffusing capacity is dependent on diffusion distance, which may vary with the type of interhaemal barrier. It has been shown that epitheliochorial placentation is a derived state and that the common ancestor of placental mammals probably had a placenta of the endotheliochorial type. Where evolutionary trends are implied for mammals as a whole or within orders such as primates they often accompany a switch in reproductive strategy that is manifested in a change of newborn state from poorly developed (altricial) to well developed (precocial).