55 research outputs found

    Identification and cardiotropic actions of sulfakinin peptides in the American lobster Homarus americanus

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    In arthropods, a group of peptides possessing a -Y(SO3H)GHM/ LRFamide carboxy-terminal motif have been collectively termed the sulfakinins. Sulfakinin isoforms have been identified from numerous insect species. In contrast, members of this peptide family have thus far been isolated from just two crustaceans, the penaeid shrimp Penaeus monodon and Litopenaeus vannamei. Here, we report the identification of a cDNA encoding prepro-sulfakinin from the American lobster Homarus americanus. Two sulfakinin-like sequences were identified within the open-reading frame of the cDNA. Based on modifications predicted by peptide modeling programs, and on homology to the known isoforms of sulfakinin, particularly those from shrimp, the mature H. americanus sulfakinins were hypothesized to be pEFDEY(SO3H)GHMRFamide (Hoa-SK I) and GGGEY(SO3H)DDY(SO3H)GHLRFamide (Hoa-SK II). Hoa-SK I is identical to one of the previously identified shrimp sulfakinins, while Hoa-SK II is a novel isoform. Exogenous application of either synthetic Hoa-SK I or Hoa-SK II to the isolated lobster heart increased both the frequency and amplitude of spontaneous heart contractions. In preparations in which spontaneous contractions were irregular, both peptides increased the regularity of the heartbeat. Our study provides the first molecular characterization of a sulfakinin-encoding cDNA from a crustacean, as well as the first demonstration of bioactivity for native sulfakinins in this group of arthropods

    \u3ci\u3eFundulus\u3c/i\u3e as the premier teleost model in environmental biology: Opportunities for new insights using genomics

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    A strong foundation of basic and applied research documents that the estuarine fish Fundulus heteroclitus and related species are unique laboratory and field models for understanding how individuals and populations interact with their environment. In this paper we summarize an extensive body of work examining the adaptive responses of Fundulus species to environmental conditions, and describe how this research has contributed importantly to our understanding of physiology, gene regulation, toxicology, and ecological and evolutionary genetics of teleosts and other vertebrates. These explorations have reached a critical juncture at which advancement is hindered by the lack of genomic resources for these species. We suggest that a more complete genomics toolbox for F. heteroclitus and related species will permit researchers to exploit the power of this model organism to rapidly advance our understanding of fundamental biological and pathological mechanisms among vertebrates, as well as ecological strategies and evolutionary processes common to all living organisms

    Alcohol management plans in Aboriginal and Torres Strait Islander (Indigenous) Australian communities in Queensland: Community residents have experienced favourable impacts but also suffered unfavourable ones

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    Background: In Australia, ‘Alcohol Management Plans’ (AMPs) provide the policy infrastructure for State and Commonwealth Governments to address problematic alcohol use among Aboriginal and Torres Strait Islanders. We report community residents’ experiences of AMPs in 10 of Queensland’s 15 remote Indigenous communities. Methods: This cross-sectional study used a two-stage sampling strategy: N = 1211; 588 (48%) males, 623 (52%) females aged ≥18 years in 10 communities. Seven propositions about ‘favourable’ impacts and seven about ‘unfavourable’ impacts were developed from semi-structured interviews. For each proposition, one-sample tests of proportions examined participant agreement and multivariable binary logistic regressions assessed influences of gender, age (18–24, 25–44, 45–64, ≥65 years), residence (≥6 years), current drinking and Indigenous status. Confirmatory factor analyses estimated scale reliability (ρ), item loadings and covariances. Results: Slim majorities agreed that: AMPs reduced violence (53%, p = 0.024); community a better place to live (54%, 0.012); and children were safer (56%, p < 0.001). More agreed that: school attendance improved (66%, p < 0. 001); and awareness of alcohol’s harms increased (71%, p < 0.001). Participants were equivocal about improved personal safety (53%, p = 0.097) and reduced violence against women (49%, p = 0.362). The seven ‘favourable’ items reliably summarized participants’ experiences of reduced violence and improved community amenity (ρ = 0.90). Stronger agreement was found for six ‘unfavourable’ items: alcohol availability not reduced (58%, p < 0.001); drinking not reduced (56%, p < 0.001)); cannabis use increased (69%, p < 0.001); more binge drinking (73%, p < 0.001); discrimination experienced (77%, p < 0.001); increased fines, convictions and criminal records for breaching restrictions (90%, p < 0.001). Participants were equivocal (51% agreed, p = 0.365) that police could enforce restrictions effectively. ‘Unfavourable’ items were not reliably reflected in one group (ρ = 0.48) but in: i) alcohol availability and consumption not reduced and ii) criminalization and discrimination. In logistic regressions, longer-term (≥ 6 years) residents more likely agreed that violence against women had reduced and that personal safety had improved but also that criminalization and binge drinking had increased. Younger people disagreed that their community was a better place to live and strongly agreed about discrimination. Current drinkers’ views differed little from the sample overall. Conclusions: The present Government review provides an opportunity to reinforce ‘favourable’ outcomes while targeting: illicit alcohol, treatment and diversion services and reconciliation of criminalization and discrimination issues. Keywords: Alcohol, Indigenous, Aboriginal and Torres Strait Islander, Australian, Legal intervention, EvaluationThe study was funded by the National Health and Medical Research Council of Australia (NHMRC, Project Grant #APP1042532) with additional support from the Australian Primary Health Care Research Institute-funded Centre for Research Excellence for the Prevention of Chronic Conditions in Rural and Remote High Risk Populations at James Cook University & University Adelaide. Associate Professor Caryn West is a National Health and Medical Research Council of Australia Early Career Research Fellow (#APP1070931). Professor Clough holds a NHMRC Career Development Award (#APP1046773)

    Effects of elevated seawater pCO2 on gene expression patterns in the gills of the green crab, Carcinus maenas

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    Background: The green crab Carcinus maenas is known for its high acclimation potential to varying environmental abiotic conditions. A high ability for ion and acid-base regulation is mainly based on an efficient regulation apparatus located in gill epithelia. However, at present it is neither known which ion transport proteins play a key role in the acid-base compensation response nor how gill epithelia respond to elevated seawater pCO2 as predicted for the future. In order to promote our understanding of the responses of green crab acid-base regulatory epithelia to high pCO2, Baltic Sea green crabs were exposed to a pCO2 of 400 Pa. Gills were screened for differentially expressed gene transcripts using a 4,462-feature microarray and quantitative real-time PCR. Results: Crabs responded mainly through fine scale adjustment of gene expression to elevated pCO2. However, 2% of all investigated transcripts were significantly regulated 1.3 to 2.2-fold upon one-week exposure to CO2 stress. Most of the genes known to code for proteins involved in osmo- and acid-base regulation, as well as cellular stress response, were were not impacted by elevated pCO2. However, after one week of exposure, significant changes were detected in a calcium-activated chloride channel, a hyperpolarization activated nucleotide-gated potassium channel, a tetraspanin, and an integrin. Furthermore, a putative syntaxin-binding protein, a protein of the transmembrane 9 superfamily, and a Cl-/HCO3 - exchanger of the SLC 4 family were differentially regulated. These genes were also affected in a previously published hypoosmotic acclimation response study. Conclusions: The moderate, but specific response of C. maenas gill gene expression indicates that (1) seawater acidification does not act as a strong stressor on the cellular level in gill epithelia; (2) the response to hypercapnia is to some degree comparable to a hypoosmotic acclimation response; (3) the specialization of each of the posterior gill arches might go beyond what has been demonstrated up to date; and (4) a re-configuration of gill epithelia might occur in response to hypercapnia

    “Being Guided”: What Oncofertility Patients’ Decisions Can Teach Us About the Efficacy of Autonomy, Agency, and Decision-Making Theory in the Contemporary Critical Encounter

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    Recent research on patient decision-making reveals a disconnect between theories of autonomy, agency, and decision-making and their practice in contemporary clinical encounters. This study examines these concepts in the context of female patients making oncofertility decisions in the United Kingdom in light of the phenomenon of “being guided.” Patients experience being guided as a way to cope with, understand, and defer difficult treatment decisions. Previous discussions condemn guided decision-making, but this research suggests that patients make an informed, autonomous decision to be guided by doctors. Thus, bioethicists must consider the multifaceted ways that patients enact their autonomy in medical encounters

    Translating shared decision-making into health care clinical practices: Proof of concepts

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    Background: There is considerable interest today in shared decision-making (SDM), defined as a decision-making process jointly shared by patients and their health care provider. However, the data show that SDM has not been broadly adopted yet. Consequently, the main goal of this proposal is to bring together the resources and the expertise needed to develop an interdisciplinary and international research team on the implementation of SDM in clinical practice using a theory-based dyadic perspective. Methods: Participants include researchers from Canada, US, UK, and Netherlands, representing medicine, nursing, psychology, community health and epidemiology. In order to develop a collaborative research network that takes advantage of the expertise of the team members, the following research activities are planned: 1) establish networking and on-going communication through internet-based forum, conference calls, and a bi-weekly e-bulletin; 2) hold a two-day workshop with two key experts (one in theoretical underpinnings of behavioral change, and a second in dyadic data analysis), and invite all investigators to present their views on the challenges related to the implementation of SDM in clinical practices; 3) conduct a secondary analyses of existing dyadic datasets to ensure that discussion among team members is grounded in empirical data; 4) build capacity with involvement of graduate students in the workshop and online forum; and 5) elaborate a position paper and an international multi-site study protocol. Discussion: This study protocol aims to inform researchers, educators, and clinicians interested in improving their understanding of effective strategies to implement shared decision-making in clinical practice using a theory-based dyadic perspective

    Instruments to assess the perception of physicians in the decision-making process of specific clinical encounters: a systematic review

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    <p>Abstract</p> <p>Background</p> <p>The measurement of processes and outcomes that reflect the complexity of the decision-making process within specific clinical encounters is an important area of research to pursue. A systematic review was conducted to identify instruments that assess the perception physicians have of the decision-making process within specific clinical encounters.</p> <p>Methods</p> <p>For every year available up until April 2007, PubMed, PsycINFO, Current Contents, Dissertation Abstracts and Sociological Abstracts were searched for original studies in English or French. Reference lists from retrieved studies were also consulted. Studies were included if they reported a self-administered instrument evaluating physicians' perceptions of the decision-making process within specific clinical encounters, contained sufficient description to permit critical appraisal and presented quantitative results based on administering the instrument. Two individuals independently assessed the eligibility of the instruments and abstracted information on their conceptual underpinnings, main evaluation domain, development, format, reliability, validity and responsiveness. They also assessed the quality of the studies that reported on the development of the instruments with a modified version of STARD.</p> <p>Results</p> <p>Out of 3431 records identified and screened for evaluation, 26 potentially relevant instruments were assessed; 11 met the inclusion criteria. Five instruments were published before 1995. Among those published after 1995, five offered a corresponding patient version. Overall, the main evaluation domains were: satisfaction with the clinical encounter (n = 2), mutual understanding between health professional and patient (n = 2), mental workload (n = 1), frustration with the clinical encounter (n = 1), nurse-physician collaboration (n = 1), perceptions of communication competence (n = 2), degree of comfort with a decision (n = 1) and information on medication (n = 1). For most instruments (n = 10), some reliability and validity criteria were reported in French or English. Overall, the mean number of items on the modified version of STARD was 12.4 (range: 2 to 18).</p> <p>Conclusion</p> <p>This systematic review provides a critical appraisal and repository of instruments that assess the perception physicians have of the decision-making process within specific clinical encounters. More research is needed to pursue the validation of the existing instruments and the development of patient versions. This will help researchers capture the complexity of the decision-making process within specific clinical encounters.</p

    Fundulus as the premier teleost model in environmental biology : opportunities for new insights using genomics

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    Author Posting. © Elsevier B.V., 2007. This is the author's version of the work. It is posted here by permission of Elsevier B.V. for personal use, not for redistribution. The definitive version was published in Comparative Biochemistry and Physiology Part D: Genomics and Proteomics 2 (2007): 257-286, doi:10.1016/j.cbd.2007.09.001.A strong foundation of basic and applied research documents that the estuarine fish Fundulus heteroclitus and related species are unique laboratory and field models for understanding how individuals and populations interact with their environment. In this paper we summarize an extensive body of work examining the adaptive responses of Fundulus species to environmental conditions, and describe how this research has contributed importantly to our understanding of physiology, gene regulation, toxicology, and ecological and evolutionary genetics of teleosts and other vertebrates. These explorations have reached a critical juncture at which advancement is hindered by the lack of genomic resources for these species. We suggest that a more complete genomics toolbox for F. heteroclitus and related species will permit researchers to exploit the power of this model organism to rapidly advance our understanding of fundamental biological and pathological mechanisms among vertebrates, as well as ecological strategies and evolutionary processes common to all living organisms.This material is based on work supported by grants from the National Science Foundation DBI-0420504 (LJB), OCE 0308777 (DLC, RNW, BBR), BES-0553523 (AW), IBN 0236494 (BBR), IOB-0519579 (DHE), IOB-0543860 (DWT), FSML-0533189 (SC); National Institute of Health NIEHS P42-ES007381(GVC, MEH), P42-ES10356 (RTD), ES011588 (MFO); and NCRR P20 RR-016463 (DWT); Natural Sciences and Engineering Research Council of Canada Discovery (DLM, TDS, WSM) and Collaborative Research and Development Programs (DLM); NOAA/National Sea Grant NA86RG0052 (LJB), NA16RG2273 (SIK, MEH,GVC, JJS); Environmental Protection Agency U91620701 (WSB), R82902201(SC) and EPA’s Office of Research and Development (DEN)

    Conservation status of the American horseshoe crab, (Limulus polyphemus): a regional assessment

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    The Nautilus Siphuncle as an Ion Pump

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    The siphuncle, which is believed to empty the newly formed chambers of the shell by a process involving the active transport of NaCl, has the metabolic, enzymatic, and morphological features of a transporting epithelium. It is capable of removing monovalent ions from solutions containing only Na+ and no Cl- or divalent ions, or only Cl- and no Na+ or divalent ions, indicating no obligatory coupling. The Na+ and Cl- are removed from native cameral fluid at approximately the same ratio. The levels of K + and the divalent ions are also lowered, but at slightly different rates. Neither H+ nor NH1 accumulate in cameral fluid to an appreciable extent
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