Search

Despite over 80 years of clinical experience with coagulation factor (F)VIII inhibitors, surprisingly little is known about the in vivo mechanism of this most serious complication of replacement therapy for hemophilia A. These neutralizing anti-drug alloantibodies arise in ~30% of patients. Inhibitor formation is T cell-dependent, but events leading up to helper T cell activation have been elusive due in part to the complex anatomy and cellular makeup of the spleen. Here, we show that FVIII antigen presentation to CD4+ T cells critically depends on a select set of several anatomically distinct antigen presenting cells, whereby marginal zone B cells, marginal zone and marginal metallophilic but not red pulp macrophages (RPMFs) participate in shuttling FVIII to the white pulp where conventional dendritic cells (DCs) prime helper T cells, which then differentiate into follicular helper T (Tfh) cells. Toll-like receptor 9 (TLR9) stimulation accelerated Tfh responses, Germinal Center and inhibitor formation, while systemic administration of FVIII alone in hemophilia A mice increased frequencies of monocyte-derived and plasmacytoid DCs. Moreover, FVIII enhanced T cell proliferation to another protein antigen (ovalbumin), and inflammatory signaling-deficient mice were less likely to develop inhibitors, indicating that FVIII may have intrinsic immunostimulatory properties. Ovalbumin, which, unlike FVIII, is absorbed into the RPMF compartment, fails to elicit T cell proliferative and antibody responses when administered at the same dose as FVIII. Altogether, we propose that an antigen trafficking pattern that results in efficient in vivo delivery to DCs and inflammatory signaling, shape the immunogenicity of FVIII.

Type I interferons (IFN) are central players in the pathogenesis of systemic lupus erythematosus (SLE) and the up-regulation of interferon-stimulated genes (ISGs) in SLE patients is subjected to increasing scrutiny as for its use in diagnosis, stratification and monitoring of SLE patients. Determinants of this immunological phenomenon are yet to be fully charted. The purpose of this systematic review was to characterize expressions of ISGs in blood of SLE patients and to analyze if they associated with core demographic and clinical features of SLE. Twenty cross-sectional, case-control studies comprising 1033 SLE patients and 602 study controls could be included. ISG fold-change expression values (SLE vs controls), demographic and clinical data were extracted from the published material and analyzed by hierarchical cluster analysis and generalized linear modelling. ISG expression varied substantially within each study with IFI27, IFI44, IFI44L, IFIT4 and RSAD2, being the top-five upregulated ISGs. Analysis of inter-study variation showed that IFI27, IFI44, IFI44L, IFIT1, PRKR and RSAD2 expression clustered with the fraction of SLE cases having African ancestry or lupus nephritis. Generalized linear models adjusted for prevalence of lupus nephritis and usage of hydroxychloroquine confirmed the observed association between African ancestry and IFI27, IFI44L, IFIT1, PRKR and RSAD2, whereas disease activity was associated with expression of IFI27 and RNASE2. In conclusion, this systematic review revealed that expression of ISGs often used for deriving an IFN signature in SLE patients were influenced by African ancestry rather than disease activity. This underscores the necessity of taking ancestry into account when employing the IFN signature for clinical research in SLE.

Mechanisms thought to regulate activated factor VIII (FVIIIa) cofactor function include A2-domain dissociation and activated protein C (APC) cleavage. Unlike A2-domain dissociation, there is no known phenotype associated with altered APC cleavage of FVIII, and biochemical studies have suggested APC plays a marginal role in FVIIIa regulation. However, the in vivo contribution of FVIIIa inactivation by APC is unexplored. Here we compared wild-type B-domainless FVIII (FVIII-WT) recombinant protein with an APC-resistant FVIII variant (FVIII-R336Q/R562Q; FVIII-QQ). FVIII-QQ demonstrated expected APC resistance without other changes in procoagulant function or A2-domain dissociation. In plasma-based studies, FVIII-WT/FVIIIa-WT demonstrated dose-dependent sensitivity to APC with or without protein S, whereas FVIII-QQ/FVIIIa-QQ did not. Importantly, FVIII-QQ demonstrated approximately fivefold increased procoagulant function relative to FVIII-WT in the tail clip and ferric chloride injury models in hemophilia A (HA) mice. To minimize the contribution of FV inactivation by APC in vivo, a tail clip assay was performed in homozygous HA/FV Leiden (FVL) mice infused with FVIII-QQ or FVIII-WT in the presence or absence of monoclonal antibody 1609, an antibody that blocks murine PC/APC hemostatic function. FVIII-QQ again demonstrated enhanced hemostatic function in HA/FVL mice; however, FVIII-QQ and FVIII-WT performed analogously in the presence of the PC/APC inhibitory antibody, indicating the increased hemostatic effect of FVIII-QQ was APC specific. Our data demonstrate APC contributes to the in vivo regulation of FVIIIa, which has the potential to be exploited to develop novel HA therapeutics.

OBJECTIVES Four-hour gastric emptying scintigraphy (GES) is the recommended method to identify both adult and childhood gastroparesis (GP). Previous pediatric studies have, however, not used this standard. We sought to determine the characteristics and outcomes of children versus adolescents with GP using the 4-hour GES evaluation. METHODS We performed a retrospective chart review of pediatric patients diagnosed with GP by 4-hour GES (>10% retention at 4 hours). Demographics, body mass index, GP-related symptoms, comorbidities, etiologies, therapies (eg, medications), healthcare utilization, and response to therapy were captured systematically. Symptoms were compared from the initial versus last gastroenterology visit. Outcomes were categorized as no improvement; improvement (resolution of at least 1 symptom while remaining on therapy); and complete resolution of symptoms. RESULTS A total of 239 subjects (12.1 ± 4.1 years [mean ± standard deviation], 70% girls) were included. The identified characteristics of childhood GP were broad with idiopathic GP being the most common etiology. Outcomes over a median of 22 months (25%-75%: 9.0-45.5 months) were 34.8% no improvement, 34.8% some improvement, and 30.3% with complete symptom resolution. Compared to younger children, adolescents had a higher female predominance (P

Human breast cancer which affects 1/8 women is rare at a cellular level. Even in the setting of germline BRCA1/BRCA2, which is present in all breast cells, solitary cancers or cancers arising at only several foci occur. The overwhelming majority of breast cells (109–1012 cells) resist transformation. Our hypothesis to explain this rareness of transformation is that mammary oncogenesis is regulated by the cell of origin’s critical window of differentiation so that target cells outside of this window cannot transform. Our novel hypothesis differs from both the multi-hit theory of carcinogenesis and the stem/progenitor cell compartmental theory of tumorigenesis and utilizes two well established murine transgenic models of breast oncogenesis, the FVB/N-Tg (MMTV-PyVT)634Mul/J and the FVB-Tg (MMTV-ErbB2) NK1Mul/J. Tail vein fibroblasts from each of these transgenics were used to generate iPSCs. When select clones were injected into cleared mammary fat pads, but not into non-orthotopic sites of background mice, they exhibited mammary ontogenesis and oncogenesis with the expression of their respective transgenes. iPSC clones, when differentiated along different non-mammary lineages in vitro, were also not able to exhibit either mammary ontogenesis or oncogenesis in vivo. Therefore, in vitro and in vivo regulation of differentiation is an important determinant of breast cancer oncogenesis.

Background Brain-derived neurotrophic factor (BDNF) is a key neurotrophin that regulates food intake and energy hemostasis. BDNF also promotes neurogenesis, neuroplasticity, and neuroprotection. There are conflicting reports regarding how intermittent fasting affects circulating BDNF levels. We tested the hypothesis that 4-week intermittent fasting from dawn to sunset (4-week-IF) would decrease circulating BDNF levels in subjects with metabolic syndrome and healthy subjects. Methods We conducted pilot studies in subjects with metabolic syndrome and healthy subjects who fasted from dawn to sunset for more than 14 h for four consecutive weeks. We measured serum BDNF levels and metabolic parameters before 4-week-IF, at the end of 4th week during 4-week-IF, and one week after 4-week-IF. Results We enrolled 28 subjects, 14 with metabolic syndrome (women/men:6/8) with a mean age of 59 years and 14 healthy subjects (women/men:1/13) with a mean age of 32 years. Overall, BDNF levels decreased at the end of 4th week during 4-week-IF compared with the levels before 4-week-IF (mean paired difference = −98.5 ng/ml, P = 0.0006). When subjects with metabolic syndrome were compared with healthy subjects, subjects with metabolic syndrome had a lower mean paired reduction in BDNF levels at the end of 4th week during 4-week-IF compared with the levels before 4-week-IF (BDNF mean paired difference = −27.6 ng/ml vs. −169.5 ng/ml, P = 0.003). Multivariate linear regression analysis showed a positive correlation between the change in tumor necrosis factor-alpha and change in BDNF levels at the end of 4th week during 4-week-IF compared with the levels before 4-week-IF in subjects with metabolic syndrome (P = 0.040) and healthy subjects (P = 0.007). The change in weight and body mass index independently predicted the change in BDNF levels 1 week after 4-week-IF compared with the levels before 4-week-IF in subjects with metabolic syndrome. Conclusion Four-week-IF resulted in a reduction in the BDNF levels at the end of 4th week during 4-week-IF. Higher BDNF levels and a lower reduction in BDNF levels at the end of 4th week during 4-week-IF compared with the levels before 4-week-IF in subjects with metabolic syndrome than healthy subjects suggest a potential BDNF resistance similar to insulin and leptin resistance in metabolic syndrome. A positive correlation between the change in BDNF and change in tumor necrosis factor-alpha levels at the end of 4th week during 4-week-IF compared with the levels before 4-week-IF suggests that BDNF is a biomarker of inflammation and endothelial dysfunction in addition to its neurotrophic and anorexigenic features.

Five Cape fur seals, Arctocephalus pusillus pusillus, 1 dusky kob, Argyrosomus coronus, and 55 silver kob, A. inodorus, collected from Cape Cross, Henties Bay, and Skeleton Coast Park, Namibia, were examined for acanthocephalans. Adults of Bolbosoma vasculosum and Corynosoma australe were recovered from 5 Cape fur seals, and cystacanths of C. australe from the single dusky kob and 3 of the silver kobs that were examined. This is the first record of B. vasculosum and the second of C. australe from the Namibian coast. Scanning electron microscopy of specimens of C. australe revealed features such as bursal papillae and micropores both on the proboscis hook surfaces and across the epidermal surface of the trunk. X-ray analyses of gallium cut hook, egg, and spines of C. australe are presented with analyses of spines of Corynosoma strumosum for comparison.

Background: Iohexol has been successfully used as a marker to assess intestinal permeability in humans and various other mammals. The objective of this study was to evaluate the use of oral iohexol as an intestinal permeability marker in four anatomically and nutritionally diverse bird species. Methods: Three dosages (1 ml/kg, 2 ml/kg, 4 ml/kg) of iohexol (755 mg/ml) were administered orally to each six clinically healthy pigeons and chickens at two-week intervals. Iohexol plasma concentration was determined 45, 90 and 180 minutes after administration. A comparative study was performed by administering iohexol twice to each six clinically healthy cockatiels and falcons, and determining iohexol plasma concentration at 45 or 90 minutes after administration. Results: The recommended iohexol dosage for permeability testing in birds was determined to be 1 ml/kg. Median plasma iohexol concentrations were 27.77 mu g/ml in pigeons, 12.97 mu g/ml in chickens, 14.24 mu g/ml in cockatiels, and 47.81 mu g/ml in falcons, 45 minutes after this dosage was administered. At 90 minutes after administration, median plasma iohexol concentrations were 40.68 mu g/ml in pigeons, 21.59 mu g/ml in chickens, 32.03 mu g/ml in cockatiels, and 55.96 mu g/ml in falcons. Conclusions and clinical relevance: Oral iohexol was a safe and feasible marker for intestinal permeability assessment in birds. Further investigations are warranted to establish species-specific reference intervals in larger numbers of healthy birds, and to examine the use of iohexol as a permeability marker in birds with disorders associated with altered intestinal permeability.

Given the success of B cell depletion therapy in multiple sclerosis (MS), deeper understanding of pathogenic B cells will be key in developing novel treatments. Notably, B cell depletion therapy leaves plasma cells and immunoglobulin levels largely intact, indicating that B cells provide pathogenic functions beyond antibodies. To better understand this, we recently developed a novel B cell-dependent, antibody-independent experimental autoimmune encephalomyelitis (EAE) mouse model of MS featuring immunoreactivity to the extracellular domains of myelin proteolipid protein (PLPECD). In contrast to a B cell-independent EAE model, we demonstrate here that PLPECD induced EAE in WT but not B cell-depleted mice, and that established disease was ameliorated by B cell depletion. We tested antigen presentation by B cells through mixed bone marrow chimeras and demonstrate that mice in which MHC II deficiency is restricted to B cells alone failed to exhibit EAE compared to MHC II sufficient mice. Given that HLA class II is the largest molecular link to MS incidence and CD4 T cells are causative in EAE, we tested B cells’ influence on CD4 T cells. In the absence of B cells, we observed not only lower activation and proliferation of CD4 T cells, but also noted a lower proinflammatory functional profile amongst the activated cells. Further, adoptively transferred CD4 T cells derived from B cell-depleted donors induced significantly less EAE compared to those from B cell-sufficient donors. These results demonstrate that antigen presentation by B cells plays a critical role in the activation, proliferation, function and pathogenicity of autoreactive CD4 T cells in demyelinating disease. Supported by grants from NIAID/NIH AI156123 and US Veterans Affairs I01BX003677.

Understanding and validating annual structures in fish otoliths are important for stock assessments and fisheries ecology. Biannual translucent zone formation has been demonstrated for 3–21 months old Namibian shallow-water hake Merluccius capensis. This paper addresses the hypothesis that the pattern continues in older fish. Otolith zone periodicity was studied for four cohorts hatched in July of 1996, 1998, 2002 and 2005, based on modal progression analysis (n = 1059). Edge analysis and marginal increment analysis were performed on otoliths representing eleven months of the year from port samples (n = 1153) from the years 2007–2015. Two to three translucent (T)-zones are formed on the hake otoliths each year, one or two between austral summer and autumn (January to April) and one in winter–spring (between July and October). Annual zones are usually the T2, T5, T8 zones (likely every third T-zone). Annual zones are not distinguishable from pseudo-annuli under the light microscope, and therefore otolith length measurements (OL) at each T-zone should be used as a guide for assigning age (9, 15 and 19 mm OL for ages 1, 2 and 3 respectively). Otolith T-zones are associated with both warm and cold periods, when they are presumably limited by temperature or dissolved oxygen concentration as well as food availability and feeding efficiency at both ends of their tolerance range. The most noticeable factor influencing the formation of translucent zones in otoliths is fish condition, not always linked with spawning (not always linked with high GSI). M. capensis otolith zonation is thus linked with their endogenous adaptation to the ecosystem, their fish physiology and also regulated by environmental variability.

The hypothesis that fast growth rates demonstrated for 3–21-month-old Merluccius capensis continue for older fish is tested. Cohort-specific growth rates of M. capensis between 6 and 65 cm total length were described using a von Bertalanffy growth function (VBGF) fitted to annual/bi-annual research survey length-frequency distributions (LFDs) from 1995 to 2011 and monthly commercial LFDs from 1998 to 2011. These data were combined with cohort analysis of younger fish from seal scat data to provide cohort-specific growth rates for cohorts hatched from 1994 to 2008. The fitted VBGF gave L t (cm) = 108.6*{1-exp[–0.199*( t (y) + 0.025)]}. M. capensis grow between 1.4 and 0.8 cm month −1 from ages 1 to 5 years, varying by 0.2 cm month −1 among cohorts. This is about twice as fast as growth rates previously estimated from otolith methods, which therefore need to be re-evaluated. It follows that M. capensis should have higher natural mortality rates and a greater stock productivity than previously believed, emphasizing the need to review this in the current stock assessment approaches.

This work investigated the potential effects of dietary garlic (Allium sativum) crude polysaccharide (GPE) (0, 0.5, 1.0, 2.0, and 4.0%/kg diet) on growth, haematological parameters, whole body composition, and resistance against low pH in African catfish, Clarias gariepinus juveniles. At the end of 60 days, fish fed GPE supplemented diets had significantly increased (P 0.05) was observed in the cumulative survival among dietary groups following a challenge with low pH, except somewhat high survival in garlic-supplemented fish especially at 72 h. Similarly, no significant difference (P > 0.05) was presented in the whole body composition and organo-somatic indices among groups. Based on the second order polynomial analysis, dietary inclusion level less than or equal to 1.88% of garlic/kg diet is estimated suitable to support growth, feed utilization, and ultimately health in C. gariepinus juvenile culture. Keywords: African catfish, Aquaculture, Clarias gariepinus, Garlic, herbs, Immunostimulants

Transmission angle control is well studied for both crank rocker and Grashof crank slider mechanisms. However, non-Grashof slider-crank mechanisms have received less attention. For these mechanisms, the fully rotatable crank constraint is removed increasing the complexity of the problem. Furthermore, methods of linkage synthesis by optimization are becoming more prevalent. When optimizing a mechanism, it is important to prevent the evaluation of non-constructible and undesirable linkages. Presented here is a method of solution rectification by means of transmission angle control for slider-crank mechanisms which can be used to parameterize a problem to prevent the evaluation of invalid linkages. The solution is kept general to include fully rotatable crank slider mechanisms as well. The solution considers both crank driven and slider driven mechanisms as well as a reversible driver mechanism. An example is provided to demonstrate the method. It will be shown that by defining a transmission angle, valid linkages can be generated preventing the evaluation of invalid solutions.

Variations in atmospheric conditions can be important factors influencing temperature dynamics within the active layer of a soil. Solar radiation and air temperature can directly alter ground surface temperatures, while variations in wind and precipitation can control how quickly heat is carried through soil pores. The presence of seasonal snow cover can also create a thermal barrier between the atmosphere and ground surface. This study examines the relation between atmospheric conditions and ground temperature variations on a deglaciated island along the Western Antarctic Peninsula. Ground temperatures were most significantly influenced by incoming solar radiation, followed by air temperature variations. When winter months were included in the comparison, the influence of air temperature increased while solar radiation became less influential, indicating that snow cover reflected solar radiation inputs, but was not thick enough to insulate the ground. When ground temperatures were compared to atmospheric conditions of preceding weeks, seasonal temperature peaks 1.6 m below ground were best related to seasonal air temperature peaks from the previous two weeks. The same ground temperature peaks were best related to seasonal solar radiation peaks of seven weeks prior. This difference was a result of temperature lags within the atmosphere.

For more than sixty years the Antarctic Peninsula has experienced significant temperature increases that have accelerated glacial retreat. Glacial losses, along with the relatively warm and moist climatic conditions of the region, have increased the rate of soil development. The objective of this study is to study the properties and genesis of soils at Cierva Point, which is located in the zone of maximum warming along the western Antarctic Peninsula. Cierva Point is a terraced, steeply sloping, ice-free peninsula containing a small retreating glacier. The peninsula contains a large penguin rookery and significant areas of moss buildup. Twenty-seven soils were described; physical and chemical properties from each horizon were analyzed. Four categories of soil were identified: acidic (pH 5), moss-dominated (high organic matter accumulations), and ornithogenic (high phosphorus accumulations). Neutral soils were newly formed soils which had undergone the least development and were located closest to the glacier margin. Acidic soils were located farthest from the glacier margin, allowing for a greater nutrient leaching to occur; these soils have extremely low pH values (as low as 3.5) but did not have the high phosphorus accumulations found in ornithogenic soils or the high soil carbon content found in moss-dominated soils. In a region with rapidly retreating glaciers, such as the Antarctic Peninsula, proximity to the glacier margin becomes an important factor determining soil properties. Soils farther from the glacier have had more time to be affected by leaching, penguin activity, and moss buildup.

Shallow-water hake (Merluccius capensis) is of considerable ecological and economic importance in the Benguela Current Large Marine Ecosystem in South Africa and Namibia. Optimal management of the resource is currently constrained by the limited understanding of migration patterns and population (stock) structure. We combined data from multiple demersal trawl surveys from the entire distribution area to estimate growth rate, mortality and spatial and temporal patterns of M. capensis. Analyses were conducted using the geostatistical model GeoPop. The complexity of the model and the amount of data required a new level of soft- and hardware performance. This was achieved by utilizing Template Model Builder and high-end computational hardware (Amazon Elastic Compute Cloud, EC2). The data and the model enabled us to follow the distribution and infer movements of M. capensis from the recruitment/nursery areas, through the juvenile phase and the adults’ migration to the spawning areas outside/upstream of the nursery areas. This revealed some previously unknown migration patterns and indicated natal homing and the existence of three primary population components in the region, namely the Walvis (central and northern Namibia), the Orange (Southern Namibia—Northern SA) and the Agulhas (Southern part of SA) components. Our results also indicated substantial regional differences in mortality. We recommend that fisheries assessment, advice and management take consideration of these aspects of the distribution and population (stock) structure of M. capensis in the Benguela Current Large Marine Ecosystem.

The soils of the South Shetland Islands, Antarctica are considered weakly developed. Chemical weathering processes are generally considered to be negligible except in areas that receive large additions of seabird guano. In this paper we describe and analyze 19 soils on Hurd Peninsula, Livingston Island in the South Shetland Island Archipelago. The soils were classified according to US Soil Taxonomy and were generally weakly developed Gelorthents, Humigelepts and Haplorthels. However, B horizon formation, rubification and increases in extractable Fe and Al were observed on toposequences of raised beaches. The deposition of tephra and/or guano is likely responsible for the chemically driven processes. Guano deposits contain phosphates and oxalic acid, causing phosphatization and/or dissolution of silicates. Input of tephra with easily weatherable minerals may account for metastable mineral formation. Tephra deposition in the oldest raised beaches has formed a fine-textured mantle overlying the coarser textured subsoils. Highly weatherable tephra, as opposed to guano deposition, appears to influence soil formation at Hurd Peninsula.

We use gonad- and body-weight data from 54,000 samples of Merluccius capensis and Merluccius paradoxus collected in all months of the years between 1991 and 2013 to infer peak spawning periods and areas in the Benguela Current Large Marine Ecosystem. We develop and apply a new gonadosomatic index threshold for identification of spawning individuals. Spawning M. capensis were observed throughout the study area, mainly in areas of about 100 m bottom depth. The highest proportions of spawning M. capensis females in the northern Benguela region were observed off central Namibia between 24.0 and 26.0°S. In the southern Benguela, peaks in the proportions of spawning M. capensis were observed in two areas off the South African West Coast (31.0–32.5°S and 34.5–36.0°S), whereas spawning females off the South African South Coast (east of 20°E) appeared to be more evenly distributed in space. Seasonality differed between areas. In the northern Benguela, the main spawning season of M. capensis appeared to be the austral winter (July–September, peaking in August), while off the South African South Coast, the main spawning season is suggested to be in summer (around January). Between these two extremes, on the western Agulhas bank in the southern Benguela, spawning peaks were observed in both summer and winter. These peaks largely coincided with peaks in phytoplankton production that are linked to upwelling conditions in the region. Hake condition decreased subsequent to the development of the gonads. The annual spawning cycle differed between small and large M. capensis. The current October–closure of the fishery in Namibia may not match the peak spawning in August/September and may need to be shifted to earlier in the year. Spawning M. paradoxus were mainly found in areas of 200–650 m bottom depths. In the northern Benguela, spawning M. paradoxus were observed as far north as 25°S in August. The proportion of spawning females peaked between 34.5°S and 36.5°S off the West Coast, and between 23.0°E and 26.5 °E off the South Coast. It was suggested that M. paradoxus spawn throughout the year off the South African coast, with increased intensity around March and August–October. The finding of multiple spawning seasons and areas of both M. capensis and M. paradoxus strongly suggest multiple stocks (reproductive units).

Background Adequately powered studies directly comparing hard clinical outcomes of darbepoetin alfa (DPO) versus epoetin alfa (EPO) in patients undergoing dialysis are lacking. Study Design Observational, registry-based, retrospective cohort study; we mimicked a cluster-randomized trial by comparing mortality and cardiovascular events in US patients initiating hemodialysis therapy in facilities (almost) exclusively using DPO versus EPO. Setting & Participants Nonchain US hemodialysis facilities; each facility switching from EPO to DPO (2003-2010) was matched for location, profit status, and facility type with one EPO facility. Patients subsequently initiating hemodialysis therapy in these facilities were assigned their facility-level exposure. Intervention DPO versus EPO. Outcomes All-cause mortality, cardiovascular mortality; composite of cardiovascular death, nonfatal myocardial infarction (MI), and nonfatal stroke. Measurements Unadjusted and adjusted HRs from Cox proportional hazards regression models. Results Of 508 dialysis facilities that switched to DPO, 492 were matched with a similar EPO facility; 19,932 (DPO: 9,465 [47.5%]; EPO: 10,467 [52.5%]) incident hemodialysis patients were followed up for 21,918 person-years during which 5,550 deaths occurred. Almost all baseline characteristics were tightly balanced. The demographics-adjusted mortality HR for DPO (vs EPO) was 1.06 (95% CI, 1.00-1.13) and was materially unchanged after adjustment for all other baseline characteristics (HR, 1.05; 95% CI, 0.99-1.12). Cardiovascular mortality did not differ between groups (HR, 1.05; 95% CI, 0.94-1.16). Nonfatal outcomes were evaluated among 9,455 patients with fee-for-service Medicare: 4,542 (48.0%) in DPO and 4,913 (52.0%) in EPO facilities. During 10,457 and 10,363 person-years, 248 and 372 events were recorded, respectively, for strokes and MIs. We found no differences in adjusted stroke or MI rates or their composite with cardiovascular death (HR, 1.10; 95% CI, 0.96-1.25). Limitations Nonrandom treatment assignment, potential residual confounding. Conclusions In incident hemodialysis patients, mortality and cardiovascular event rates did not differ between patients treated at facilities predominantly using DPO versus EPO.

Otoliths collected at least monthly from scat samples of Cape fur seals Arctocephalus pusillus are used to show that shallow-water hake Merluccius capensis from the northern Benguela develop three translucent zones in their first 1·5 years of life. The novel sampling approach provided otoliths that belonged to four M. capensis cohorts of approximate known age (hatched in 1996, 1998, 2002 and 2005), allowing age verification. Following spawning in austral winter, translucent zones consistently formed first in summer and autumn (T1), then in winter and spring (T2) and again in summer and autumn (T3), with no difference in appearance of the zones (biannuli) for the four cohorts considered. The second translucent zone is usually the first true annulus (year mark). It forms during July to September in fish of 15-20 cm total length (LT ). Formation of the translucent zones appears to be determined by fish length or age, rather than by exogenous cues. It is suggested that length measurements should be used to help determine the first age group; fish with a translucent zone marked at otolith lengths >7·5 mm should be termed 1 year-old fish. Ages of M. capensis used in previous stock assessment models have been overestimated. Biannuli are an unusual occurrence in fish otoliths in general, but have been observed in other Merluccius species.

The effects of climate change along the climatically sensitive Western Antarctic Peninsula (WAP) on active layer dynamics have just begun to be monitored. But extreme climates and difficult access make borehole installation here challenging. This study was designed to examine the ability of two commonly used, minimally intrusive techniques (the Stefan and Kudryavtsev equations) to predict active layer temperature dynamics and maximum active layer thickness (ALT) on Amsler Island, on the WAP. The ALT in soils and unconsolidated materials was predicted to be between 4.7 and 8.7 m, and between 11.9 and 18.6 m in bedrock, consistent with measurements made in a 14.6 m deep borehole. The thermal model HYDRUS accurately predicted temperature dynamics at several monitored borehole depths. The success of the HYDRUS method indicates that the model can be a useful tool in predicting active layer temperatures and approximating ALTs in regions that are too difficult to install monitoring boreholes. Copyright © 2015 John Wiley & Sons, Ltd.

We investigate the spatial distributions of juvenile and adult hake Merluccius capensis on the Namibian continental shelf using data from 25 biomass surveys (1990–2007) to identify (i) nursery/spawning areas, their spatial or temporal separation and change and (ii) length, depth and latitude preference patterns. The density of fish (number-of-fish per 30-min-haul) was examined in relation to fish total length (TL) and latitude and TL and bottom depth. Nursery aggregations were most frequent in central (22–25°S) and southern (26–29°S) Namibia, increasing in density in the south since 2000. Hatch dates of ≤17 cm fish were calculated from juvenile growth rates. Peaks occurred in winter and summer-autumn in the centre and slightly later in the south. Spawning areas appear to have shifted southward since the late 1970s, showing the plasticity of this stock as a response to fishing pressure and environmental variability and change. Merluccius capensis show a stable pattern of latitude preference over the 25 surveys examined. They first occur on the mid-shelf

Activated factor VIII (FVIIIa) is an essential cofactor in the intrinsic tenase (Xase) enzyme complex that generates factor Xa and propagates clot formation. The FVIIIa heterotrimer is comprised of a metal ion linked dimer (A1/A3-C1-C2 domains) that is associated with the A2 domain by weak non-covalent interactions. Regulation of FXa formation by the intrinsic Xase enzyme complex occurs by FIXa inhibition and mechanisms contributing to FVIIIa inactivation, including: 1) rapid A2 domain dissociation and 2) activated protein C (APC) cleavage of FVIIIa. While FVIIIa inactivation by APC is considered important, there are surprisingly no in vivo studies documenting the hemostatic role of APC in FVIIIa regulation. Further, published data demonstrate APC cleavage of FVIIIa at physiologic protein concentrations occurs over hours while A2 dissociation occurs rapidly over minutes. Thus, it is thought that the predominant mechanism of FVIIIa inactivation is A2 dissociation and APC likely plays a marginal role in FVIIIa regulation. Additionally, unlike described A2 mutations that enhance dissociation and cause hemophilia A (HA), there is no known disease state attributed to altered FVIIIa cleavage by APC. This is in contrast to FVIII's homologous protein, FVa, whereby resistance to APC cleavage is the most common inherited thrombophilia (FV-Leiden [FVL]). Understanding the physiologically relevant mechanisms of FVIIIa inactivation has immediate clinical applicability for understanding safety considerations in HA therapeutics that bypass FVIIIa regulation (FVIII mimetic antibodies, e.g. emicizumab). Further, as evidenced by successful hemophilia B gene therapy trials using a gain of function FIX variant (FIX-Padua), altering FVIIIa inactivation could be exploited for therapeutic benefit in the setting of gene transfer. We aimed to determine the in vivo hemostatic role of APC in FVIIIa regulation and pair these studies with purified system analysis. We introduced Arg to Gln mutations at FVIII APC cleavage sites (R336Q and R562Q, herein called FVIII-QQ) on a B-domain deleted FVIII (FVIII-WT) backbone and produced recombinant FVIII-QQ and FVIII-WT. Unlike FVIII-WT, western blot analysis of FVIII-QQ incubated with APC and phospholipids had no evidence of cleavage. Enzyme kinetic studies using purified components demonstrated no appreciable difference in the Km or Vmax for FX within the intrinsic Xase enzyme complex or A2 dissociation of FVIII-QQ relative to FVIII-WT. These data confirmed no unexpected differences in FVIII-QQ relative to FVIII-WT. To begin to evaluate the role of APC in FVIIIa regulation, we measured thrombin generation in murine and human HA plasma reconstituted with FVIII-QQ or FVIII-WT in the presence of increasing APC concentrations. The IC50 of APC was 2-3-fold higher for FVIII-QQ than FVIII-WT. To evaluate the in vivo hemostatic effect of APC in FVIIIa regulation, HA mice were infused with FVIII-QQ or FVIII-WT and evaluated by tail clip injury and 7.5% FeCl3 carotid artery occlusion models. Required doses of FVIII-QQ to normalize blood loss from a tail clip assay and time to vessel occlusion in a FeCl3 assay were 4-5 fold lower than necessary FVIII-WT doses; the superior hemostatic effect of FVIII-QQ supported the physiologic significance of APC in FVIIIa inactivation. To isolate the role of APC in FVIIIa regulation from APC inactivation of FVa, we backcrossed HA mice with FVL mice to create homozygous HA/FVL mice. HA/FVL mice were infused with FVIII-QQ or FVIII-WT and underwent tail clip assay analysis. Doses of FVIII-QQ required to normalize blood loss were again less than FVIII-WT. To further isolate the enhanced hemostatic effect of FVIII-QQ to APC resistance, we performed the tail clip assay in HA/FVL mice infused with FVIII-QQ or FVIII-WT in the presence or absence of MPC1609, an antibody that blocks murine APC function (Xu et al. J Thromb Haemost 2008). In the presence of MPC1609, the same dose of FVIII-WT and FVIII-QQ was required to normalize blood loss (Figure 1). Collectively, our in vitro and in vivo data support the physiologic significance of APC in FVIIIa regulation. To our knowledge these data are the first to demonstrate the in vivo hemostatic effect of APC in FVIIIa inactivation. Our data may be translated to rationally exploit APC regulation of FVIIIa to develop novel HA therapeutics or further delineate safety considerations in therapies that bypass FVIIIa regulation. Figure 1 Disclosures Camire: Pfizer: Research Funding. George:University of Pennyslvania: Employment; Pfizer: Consultancy; Avrobio: Membership on an entity's Board of Directors or advisory committees.

Wilhelm, M. R., Roux, J-P., Moloney, C. L., and Jarre, A. 2013. Data from fur seal scats reveal when Namibian Merluccius capensis are hatched and how fast they grow. – ICES Journal of Marine Science, 70: . Scat samples were collected regularly at several breeding colonies of Cape fur seals along the Namibian coast. Merluccius capensis otoliths were obtained from these samples, identified, and measured. Cohorts were easily distinguishable using otolith length measurements converted to fish total length. Growth rates of 2- to 21-month-old hake and hatch dates for each of 15 cohorts were estimated from September 1994 to October 2009 (1994–2008 cohorts) using a Schnute growth function and a non-linear mixed-effects model. The function describing growth of these young hake was length Lt (cm) at age t (years) Lt = 3.17 + (25.0 − 3.17) × [1 − e−0.665 × (t − 0.140)]/[1 − e−0.665 × (1.74–0.140)]. Cohort-specific random effects showed a population hatch date estimate of 31 July (austral winter), varying by 94 days among cohorts, from 31 May (1996 cohort) to 1 September (2004 cohort). The mean growth rate from ages 6 to 12 months was 1.26 cm month−1 for the population, ranging between 0.97 cm month−1 (1996 cohort) and 1.38 cm month−1 (2004 cohort). As this rate is almost double the previously estimated value, which is currently used in the stock assessment models, this result may have major implications for the current stock assessment results and the management of the stock. Re-examination of growth rates needs to be extended to older fish.