In vitro characterization of CT-001-a short-acting factor VIIa with enhanced prohemostatic activity.

BACKGROUND: Traumatic injury and the associated acute bleeding are leading causes of death in people aged 1 to 44 years. Acute bleeding in pathological and surgical settings also represents a significant burden to the society. Yet there are no approved hemostatic drugs currently available. While clinically proven as an effective pro-coagulant, activated factor VII (FVIIa) use in acute bleeding has been hampered by unwanted thromboembolic events. Enhancing the ability of FVIIa to quickly stop a bleed and clear rapidly from circulation may yield an ideal molecule suitable for use in patients with acute bleeding. OBJECTIVES: To address this need and the current liability of FVIIa, we produced a novel FVIIa molecule (CT-001) with enhanced potency and shortened plasma residence time by cell line engineering and FVIIa protein engineering for superior efficacy for acute bleeding and safety. METHODS: To address safety, CT-001, a FVIIa protein with 4 desialylated N-glycans was generated to promote active recognition and clearance via the asialoglycoprotein receptor. To enhance potency, the gamma-carboxylated domain was modified with P10Q and K32E, which enhanced membrane binding. RESULTS: Together, these changes significantly enhanced potency and clearance while retaining the ability to interact with the key hemostatic checkpoint proteins antithrombin and tissue factor pathway inhibitor. CONCLUSIONS: These results demonstrate that a FVIIa molecule engineered to combine supra-physiological activity and shorter duration of action has the potential to overcome the current limitations of recombinant FVIIa to be a safe and effective approach to the treatment of acute bleeding.

Seasonal and successional dynamics of size-dependent plant demographic rates in a tropical dry forest.

Tropical forests are globally important for biodiversity conservation and climate change mitigation but are being converted to other land uses. Conversion of seasonally dry tropical forests (SDTF) is particularly high while their protection is low. Secondary succession allows forests to recover their structure, diversity and composition after conversion and subsequent abandonment and is influenced by demographic rates of the constituent species. However, how these rates vary between seasons for different plant sizes at different successional stages in SDTF is not known. The effect of seasonal drought may be more severe early in succession, when temperature and radiation are high, while competition and density-dependent processes may be more important at later stages, when vegetation is tall and dense. Besides, the effects of seasonality and successional stage may vary with plant size. Large plants can better compete with small plants for limiting resources and may also have a greater capacity to withstand stress. We asked how size-dependent density, species density, recruitment and mortality varied between seasons and successional stages in a SDTF. We monitored a chronosequence in Yucatan, Mexico, over six years in three 0.1 ha plots in each of three successional stages: early (3-5 years-old), intermediate (18-20 years-old) and advanced (>50 years-old). Recruitment, mortality and species gain and loss rates were calculated from wet and dry season censuses separately for large (diameter > 5 cm) and small (1-5 cm in diameter) plants. We used linear mixed-effects models to assess the effects of successional stage, seasonality and their changes through time on demographic rates and on plant and species density. Seasonality affected demographic rates and density of large plants, which exhibited high wet-season recruitment and species gain rates at the early stage and high wet-season mortality at the intermediate stage, resulting in an increase in plant and species density early in succession followed by a subsequent stabilization. Small plant density decreased steadily after only 5 years of land abandonment, whereas species density increased with successional stage. A decline in species dominance may be responsible for these contrasting patterns. Seasonality, successional stage and their changes through time had a stronger influence on large plants, likely because of large among-plot variation of small plants. Notwithstanding the short duration of our study, our results suggest that climate-change driven decreases in rainy season precipitation may have an influence on successional dynamics in our study forest as strong as, or even stronger than, prolonged or severe droughts during the dry season.

How training citizen scientists affects the accuracy and precision of phenological data.

Monitoring plant and animal phenology is a critical step to anticipating and predicting changes in species interactions and biodiversity. Because phenology necessarily involves frequent and repeated observations over time, citizen scientists have become a vital part of collecting phenological data. However, there is still concern over the accuracy and precision of citizen science data. It is possible that training citizen scientists can improve data quality though there are few comparisons of trained and untrained citizen scientists in the ability of each to accurately and precisely measure phenology. We assessed how three types of observers-experts, trained citizen scientists that make repeated observations, and untrained citizen scientists making once-per-year observations-differ in quantifying temporal change in flower and fruit abundance of American mountain ash trees (Sorbus americana Marsh.) and arthropods in Acadia National Park, Maine, USA. We found that trained more so than untrained citizen science observers over- or under-estimated abundances leading to precise but inaccurate characterizations of phenological patterns. Our results suggest a new type of bias induced by repeated observations: A type of learning takes place that reduces the independence of observations taken on different trees or different dates. Thus, in this and many other cases, having individuals make one-off observations of marked plants may produce data as good if not better than individuals making repeated observations. For citizen science programs related to phenology, our results underscore the importance of (a) attracting the most number of observers possible even if they only make one observation, (b) producing easy-to-use and informative data sheets, and

Population trends influence species ability to track climate change.

Shifts of distributions have been attributed to species tracking their fundamental climate niches through space. However, several studies have now demonstrated that niche tracking is imperfect, that species' climate niches may vary with population trends, and that geographic distributions may lag behind rapid climate change. These reports of imperfect niche tracking imply shifts in species' realized climate niches. We argue that quantifying climate niche shifts and analyzing them for a suite of species reveal general patterns of niche shifts and the factors affecting species' ability to track climate change. We analyzed changes in realized climate niche between 1984 and 2012 for 46 species of North American birds in relation to population trends in an effort to determine whether species differ in the ability to track climate change and whether differences in niche tracking are related to population trends. We found that increasingly abundant species tended to show greater levels of niche expansion (climate space occupied in 2012 but not in 1980) compared to declining species. Declining species had significantly greater niche unfilling (climate space occupied in 1980 but not in 2012) compared to increasing species due to an inability to colonize new sites beyond their range peripheries after climate had changed at sites of occurrence. Increasing species, conversely, were better able to colonize new sites and therefore showed very little niche unfilling. Our results indicate that species with increasing trends are better able to geographically track climate change compared to declining species, which exhibited lags relative to changes in climate. These findings have important implications for understanding past changes in distribution, as well as modeling dynamic species distributions in the face of climate change.

Predicting shifts in parasite distribution with climate change: a multitrophic level approach.

Climate change likely will lead to increasingly favourable environmental conditions for many parasites. However, predictions regarding parasitism's impacts often fail to account for the likely variability in host distribution and how this may alter parasite occurrence. Here, we investigate potential distributional shifts in the meningeal worm, Parelaphostrongylosis tenuis, a protostrongylid nematode commonly found in white-tailed deer in North America, whose life cycle also involves a free-living stage and a gastropod intermediate host. We modelled the distribution of the hosts and free-living larva as a complete assemblage to assess whether a complex trophic system will lead to an overall increase in parasite distribution with climate change, or whether divergent environmental niches may promote an ecological mismatch. Using an ensemble approach to climate modelling under two different carbon emission scenarios, we show that whereas the overall trend is for an increase in niche breadth for each species, mismatches arise in habitat suitability of the free-living larva vs. the definitive and intermediate hosts. By incorporating these projected mismatches into a combined model, we project a shift in parasite distribution accounting for all steps in the transmission cycle, and identify that overall habitat suitability of the parasite will decline in the Great Plains and southeastern USA, but will increase in the Boreal Forest ecoregion, particularly in Alberta. These results have important implications for wildlife conservation and management due to the known pathogenicity of parelaphostrongylosis to alternate hosts including moose, caribou and elk. Our results suggest that disease risk forecasts which fail to consider biotic interactions may be overly simplistic, and that accounting for each of the parasite's life stages is key to refining predicted responses to climate change.

Role of Parent and Peer Relationships and Individual Characteristics in Middle School Children's Behavioral Outcomes in the Face of Community Violence.

This study examines processes linking inner-city community violence exposure to subsequent internalizing and externalizing problems. Hypothesized risk and protective factors from three ecological domains -- children's parent and peer relationships and individual characteristics -- were examined for mediating, moderating or independent roles in predicting problem behavior among 667 children over three years of middle school. Mediation was not found. However, parent and peer variables moderated the association between exposure and internalizing problems. Under high exposure, normally protective factors (e.g., attachment to parents) were less effective in mitigating exposure's effects than under low exposure; attachment to friends was more effective. Individual competence was independently associated with decreased internalizing problems. Variables from all domains, and exposure, were independently associated with externalizing problems. Protective factors (e.g., parent attachment) predicted decreased problems; risk factors (e.g., friends' delinquency) predicted increased problems. Results indicate community violence reduction as essential in averting inner-city adolescents' poor behavioral outcomes.

Trends in adult attitudes toward secondhand smoke in Indiana, 2002-2007: the impact of smoking status.

PURPOSE: As more research has been distributed through the media about the negative health impact of exposure to secondhand smoke (SHS), the public's support for smoke-free policies has increased. The purpose of this study was to evaluate trends in knowledge and attitudes about SHS exposure among Indiana adults by smoking status. METHODS: Study data were from four cross-sectional studies previously conducted by the Indiana Tobacco Prevention and Cessation Agency using the Adult Tobacco Survey protocol between the years 2002 and 2007. RESULTS: Eighteen questions were identified as addressing SHS, 16 of which were available for more than 1 year and were evaluated for time trends. Significant overall trends toward increased awareness of SHS's health effects and support for smoking bans were noted in 10 of the 16 questions analyzed. No significant overall change, positive or negative, occurred in the remaining six questions. When responses were analyzed by smoking status, never smokers and former smokers consistently exhibited higher rates of anti-SHS sentiments and knowledge of SHS than did current smokers. CONCLUSIONS: In general, the trends are encouraging to public health efforts to raise awareness about SHS, but there remains much room for improvement, particularly among current smokers.

Potent triazolothione inhibitor of heat-shock protein-90.

Heat-shock protein-90 is an attractive target for anticancer drugs, as heat-shock protein-90 blockers such as the ansamycin 17-(allylamino)-17-demethoxygeldanamycin greatly reduce the expression of many signaling molecules that are disregulated in cancer cells and are key drivers of tumor growth and metastasis. While 17-(allylamino)-17-demethoxygeldanamycin has shown promise in clinical trials, this compound class has significant template-related drawbacks. In this paper, we describe a new, potent non-ansamycin small-molecule inhibitor of heat-shock protein-90, BX-2819, containing resorcinol and triazolothione rings. Structural studies demonstrate binding of BX-2819 to the ADP/ATP-binding pocket of heat-shock protein-90. The compound blocked expression of heat-shock protein-90 client proteins in cancer cell lines and inhibited cell growth with a potency similar to 17-(allylamino)-17-demethoxygeldanamycin. In a panel of four cancer cell lines, BX-2819 blocked growth with an average IC(50) value of 32 nM (range of 7-72 nM). Efficacy studies demonstrated that treatment with BX-2819 significantly inhibited the growth of NCI-N87 and HT-29 tumors in nude mice, consistent with pharmacodynamic studies showing inhibition of heat-shock protein-90 client protein expression in tumors for greater than 16 h after dosing. These data support further studies to assess the potential of BX-2819 and related analogs for the treatment of cancer.

Stage-structured matrix models for organisms with non-geometric development times.

Matrix models have been used to model population growth of organisms for many decades. They are popular because of both their conceptual simplicity and their computational efficiency. For some types of organisms they are relatively accurate in predicting population growth; however, for others the matrix approach does not adequately model growth rate. One of the reasons for the lack of accuracy is that most matrix-based models implicitly assume a specific degree of variability in development times for the organism. Because the variability is implicit, the implied variances are often not verified with experimental data. In this paper, we shall present extensions to the stage-classified matrix models so that organisms with arbitrary means and standard deviations of development times can be modeled.

Intervening processes between youths' exposure to community violence and internalizing symptoms over time: the roles of social support and coping.

The roles of social support and coping as intervening processes between exposure to community violence and internalizing symptoms were examined longitudinally among a community sample of 667 middle school students in the inner city. After controlling for potential confounders (e.g., social desirability, victimization and witnessing of family violence, guardian's psychological symptomatology), internalizing symptoms at Year 2 were predicted by hypothesized changes over 1 year, such that increased community violence exposure, decreased guardian and peer support, and increased use of defensive and confrontational behavioral coping were related to more internalizing symptoms of anxiety, depression and PTSD, although some of these relations varied by gender. The relations between internalizing symptoms at Year 3 and increased changes in exposure to community violence over 2 years were moderated by social support and/or coping, such that decreased guardian support and increased use of defensive and confrontational coping were generally associated with more symptoms for boys exposed to community violence. Girls who witnessed increased community violence and who increased their use of defensive or confrontational coping experienced more internalizing symptoms. The findings underscore the importance of developmental and contextual considerations in the design and implementation of interventions.

Physical child abuse and adolescent violent delinquency: the mediating and moderating roles of personal relationships.

Adolescent personal relationships with parents and peers are studied for their mediating and moderating roles in the effect of preadolescent physical abuse on adolescent violent delinquency. One hundred physically abused preadolescents and 100 matched nonabused classmates were studied at 10 and 16 years. Adolescent attachment to parents and verbal and physical abuse in relationships with parents during adolescence mediated between preadolescent abuse and later violent delinquency. Friends' delinquency in adolescence and verbal and physical abuse with best friends in adolescence moderated the relationship between early abuse and later violent delinquency. Low levels of delinquency among friends significantly decreased risk for violent delinquent outcome for abused as contrasted to nonabused adolescents. Abusive behavior with best friends exacerbated risk for violent delinquent outcome more for abused than for nonabused adolescents. Attachment to friends was not found to play a significant role in the relationship between childhood abuse and adolescent violent delinquency.

Indolinone based phosphoinositide-dependent kinase-1 (PDK1) inhibitors. Part 2: optimization of BX-517.

Based on the lead compound BX-517, a series of C-4' substituted indolinones have been synthesized and evaluated for PDK1 inhibition. Modification at C-4' of the pyrrole afforded potent compounds (7b and 7d) with improved solubility and ADME properties. In this letter, we describe the synthesis, selectivity profile, and pharmacokinetic data of selected compounds.

Adolescent suicidal behavior: associations with preadolescent physical abuse and selected risk and protective factors.

OBJECTIVES: To determine whether preadolescent physical abuse raises the risk of adolescent suicidal behavior, to examine potential mediators and moderators of the relationship between preadolescent abuse and adolescent suicidality, and to examine whether distal (preadolescent) risk factors add to proximal (adolescent) factors in predicting suicidality. METHOD: Seventy-five physically abused preadolescents on the New York City Maltreatment Register and 78 controls were studied at ages 10.5 and 16.5 years. Adolescent suicidal ideation and attempts and hypothesized risk and protective factors were assessed by self-report, parent interview, and teacher ratings. Data were analyzed by logistic regression. RESULTS: Preadolescent physical abuse was a robust, largely unmediated, independent predictor of adolescent suicidality. Only adolescent internalizing problems mediated the relationship. No risk factors moderated the relationship. Adolescent attachment to parents and internalizing problems contributed independently to the prediction of suicidality risk in abused and control subjects. No preadolescent risk or protective factors added to the predictions beyond risk deriving from preadolescent abuse. CONCLUSIONS: The association between preadolescent physical abuse and adolescent suicidality is largely unmediated and unmoderated by well-documented risk factors for suicidality. Therefore, comprehensive interventions to reduce abusive parenting must begin when families enter the child protection system, along with therapeutic interventions with the children and adolescents themselves.

Indolinone based phosphoinositide-dependent kinase-1 (PDK1) inhibitors. Part 1: design, synthesis and biological activity.

HTS screening identified 1 with micromolar inhibitory activity against PDK1. Optimization of 1 afforded 4i (BX-517) which has single-digit nanomolar activity against PDK1 and excellent selectivity against PKA.