217 research outputs found

    The diversity of bioactive proteins in Australian snake venoms

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    Australian elapid snakes are among the most venomous in the world. Their venoms contain multiple components that target blood hemostasis, neuromuscular signaling, and the cardiovascular system. We describe here a comprehensive approach to separation and identification of the venom proteins from 18 of these snake species, representing nine genera. The venom protein components were separated by two-dimensional PAGE and identified using mass spectrometry and de novo peptide sequencing. The venoms are complex mixtures showing up to 200 protein spots varying in size from 10. These include many proteins identified previously in Australian snake venoms, homologs identified in other snake species, and some novel proteins. In many cases multiple trains of spots were typically observed in the higher molecular mass range (> 20 kDa) (indicative of post-translational modification). Venom proteins and their post-translational modifications were characterized using specific kantibodies, phosphoprotein- and glycoprotein-specific stains, enzymatic digestion, lectin binding, and antivenom reactivity. In the lower molecular weight range, several proteins were identified, but the predominant species were phospholipase A(2) and alpha-neurotoxins, both represented by different sequence variants. The higher molecular weight range contained proteases, nucleotidases, oxidases, and homologs of mammalian coagulation factors. This information together with the identification of several novel proteins (metalloproteinases, vespryns, phospholipase A(2) inhibitors, protein-disulfide isomerase, 5'-nucleotidases, cysteinerich secreted proteins, C-type lectins, and acetylcholinesterases) aids in understanding the lethal mechanisms of elapid snake venoms and represents a valuable resource for future development of novel human therapeutics

    Relationships between maternal overweight prior to pregnancy, feeding mode and infant feeding beliefs and practices

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    Aim To examine whether pre-pregnancy weight status was associated with maternal feeding beliefs and practices in the early post-partum period. Methods Secondary analysis of longitudinal data from Australian mothers. Participants (N=486) were divided into two weight status groups based on self-reported pre-pregnancy weight and measured height: healthy weight (BMI <25kg/m2; n=321) and overweight (BMI>25kg/m2; n=165). Feeding beliefs and practices were self-reported via an established questionnaire that assessed concerns about infant overeating and undereating, awareness of infant cues, feeding to a schedule, and using food to calm. Results Infants of overweight mothers were more likely to have been given solid foods in the previous 24hrs (29% vs 20%) and fewer were fully breastfed (50% vs 64%). Multivariable regression analyses (adjusted for maternal education, parity, average infant weekly weight gain, feeding mode and introduction of solids) revealed pre-pregnancy weight status was not associated with using food to calm, concern about undereating, awareness of infant cues or feeding to a schedule. However feeding mode was associated with feeding beliefs and practices. Conclusions Although no evidence for a relationship between maternal weight status and early maternal feeding beliefs and practices was observed, differences in feeding mode and early introduction of solids was observed. The emergence of a relationship between feeding practices and maternal weight status may occur when the children are older, solid feeding is established and they become more independent in feeding

    Crystallization and preliminary X-ray diffraction data for a purple acid phosphastase from sweet potato

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    Purple acid phosphatase from sweet potato is a homodimer of 110 kDa. Two forms of the enzyme have been characterized. One contains an Fe-Zn centre similar to that previously reported for red kidney bean purple acid phosphatase. Another isoform, the subject of this work, is the first confirmed example of an Fe-Mn-containing enzyme. Crystals of this protein have been grown from PEG 6000. They have unit-cell parameters a = b = 118.4, c = 287.4 Angstrom and have the symmetry of space group P6(5)22, with one dimer per asymmetric unit. Diffraction data collected using a conventional X-ray source from a cryocooled crystal extend to 2.90 Angstrom resolution. The three-dimensional structure of the enzyme will provide insight into the coordination of this novel binuclear metal centre

    Expression of CD45RC and Ia Antigen in the Spinal Cord in Acute Experimental Allergic Encephalomyelitis: An Immunocytochemical and Flow Cytometric Study

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    We performed immunocytochemical studies to analyze the inflammatory infiltrate and major histocompatibility complex class II (Ia) antigen expression in the spinal cord of Lewis rats with acute experimental allergic encephalomyelitis (EAE) induced by inoculation with myelin basic protein and adjuvants. Using antibodies to lymphocyte markers and other monoclonal antibodies we found that during clinical episodes the inflammatory infiltrate was chiefly composed of T lymphocytes and macrophages. The majority of cells in the inflammatory infiltrate were stained by the W3/25 antibody to CD4 and a proportion was stained by OX22 which labels the high molecular weight form of the leucocyte common antigen (CD45RC). CDB+ T cells were sparse and B cells were not detected. There was minimal staining with the OX39 antibody to the interleukin-2 receptor. Presumptive microglia, identified by their dendritic morphology, expressed Ia antigen during the clinical episodes and after recovery. The prominence of Ia antigen expression after recovery could indicate that this la expression was associated with downregulation of the encephalitogenic immune response. We also performed flow cytometry studies on cells extracted from the spinal cord of rats before and during attacks of EAE. With flow cytometry, we found that in established disease a mean of 83(SD, 23)% of CD2+ cells were CD4+, and a mean of 27(SD, 12)% of CD2+ cells were CD45RC+. In rats sampled on the first day of signs, a mean of 43(SD, 22)% of CD2+ cells were CD45RC+. In the cells extracted from the spinal cord of rats with established disease a mean of 47(SD, 32)% of macrophages were CD45RC+. Our study has combined an immunocytochemical assessment of tissue sections with quantitative flow cytometry assessment of cells extracted from the spinal cord of rats with acute EAE. We have shown that the majority of T lymphocytes in the spinal cord are CD45RC-. We have also found prominent Ia expression on dendritic cells in acute EAE and after clinical recovery

    Conflict and user involvement in drug misuse treatment decision-making: a qualitative study

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    <p>Abstract</p> <p>Background</p> <p>This paper examines client/staff conflict and user involvement in drug misuse treatment decision-making.</p> <p>Methods</p> <p>Seventy-nine in-depth interviews were conducted with new treatment clients in two residential and two community drug treatment agencies. Fifty-nine of these clients were interviewed again after twelve weeks. Twenty-seven interviews were also conducted with staff, who were the keyworkers for the interviewed clients.</p> <p>Results</p> <p>Drug users did not expect, desire or prepare for conflict at treatment entry. They reported few actual conflicts within the treatment setting, but routinely discussed latent conflicts – that is, negative experiences and problematic aspects of current or previous treatment that could potentially escalate into overt disputes. Conflict resulted in a number of possible outcomes, including the premature termination of treatment; staff deciding on the appropriate outcome; the client appealing to the governance structure of the agency; brokered compromise; and staff skilfully eliciting client consent for staff decisions.</p> <p>Conclusion</p> <p>Although the implementation of user involvement in drug treatment decision-making has the potential to trigger high levels of staff-client conflict, latent conflict is more common than overt conflict and not all conflict is negative. Drug users generally want to be co-operative at treatment entry and often adopt non-confrontational forms of covert resistance to decisions about which they disagree. Staff sometimes deploy user involvement as a strategy for managing conflict and soliciting client compliance to treatment protocols. Suggestions for minimising and avoiding harmful conflict in treatment settings are given.</p

    Eating for 1, Healthy and Active for 2; feasibility of delivering novel, compact training for midwives to build knowledge and confidence in giving nutrition, physical activity and weight management advice during pregnancy

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    Gold OABackground: Women in Wales are more likely to be obese in pregnancy than in any other United Kingdom (UK) country. Midwives are ideally placed to explore nutrition, physical activity and weight management concerns however qualitative studies indicate they lack confidence in raising the sensitive issue of weight. Acknowledging this and the reality of finite time and resources, this study aimed to deliver compact training on nutrition, physical activity and weight management during pregnancy to increase the knowledge and confidence of midwives in this subject. Methods A compact training package for midwives was developed comprising of evidence based nutrition, physical activity and weight management guidance for pregnancy. Training was promoted via midwifery leads and delivered within the Health Board. Questionnaires based on statements from national public health guidance were used to assess changes in self-reported knowledge and confidence pre and post training. Descriptive statistics were applied and 95% confidence intervals were calculated. Results 43 midwives registered for training, 32 (74%) attended and completed the questionnaires. Although, pre training knowledge and confidence varied between participants, statistically significant improvements in self-reported knowledge and confidence were observed post training. 97% indicated knowledge of pregnancy specific food and nutrition messages as ‘better’ (95% CI 85 to 100), as opposed to 3% stating ‘stayed the same’ – 60% stated ‘much better’. 83% indicated confidence to explain the risks of raised BMI in pregnancy was either ‘much’ or ‘somewhat better’ (95% CI 66 to 93), as opposed to 17% stating ‘stayed the same’. 89% indicated confidence to discuss eating habits and physical activity was ‘much’ or ‘somewhat better’ (95% CI 73 to 97) as opposed to 11% stating ‘stayed the same’. Emergent themes highlighted that training was positively received and relevant to midwifery practice. Conclusions This study provides early indications that a compact nutrition, physical activity and weight management training package improves midwives self-reported knowledge and confidence. Cascading training across the midwifery service in the Health Board and conducting further studies to elicit longer term impact on midwifery practice and patient outcomes are recommended

    Socio-semiotics and the symbiosis of humans, horses, and objects in later Iron Age Britain

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    This is an Accepted Manuscript of an article published by Taylor & Francis in Archaeological Journal on 14/03/2018, available online: https://www.tandfonline.com/doi/full/10.1080/00665983.2018.1441105Using an approach derived from material culture studies and semiotics, this paper addresses possible relationships between humans and horses in the British Iron Age.Through a study of the dominance of horse imagery found on Iron Age British coinage, specifically the Western coinage traditionally attributed to the 'Dobunni', the author explores how it may reflect possible relationships between humans and horses and their personhood therein. Drawing on wider faunal and metalwork evidence it is argued that these coins could be interpreted as a manifestation of the complex perspectives surrounding a symbiotic relationship between humans and horses

    Protocol for a randomized controlled trial of a specialized health coaching intervention to prevent excessive gestational weight gain and postpartum weight retention in women: the HIPP study

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    BackgroundPregnancy is a time of significant physiological and physical change for women. In particular, it is a time at which many women are at risk of gaining excessive weight. We describe the rationale and methods of the Health in Pregnancy and Post-birth (HIPP) Study, a study which aims primarily to determine the effectiveness of a specialized health coaching (HC) intervention during pregnancy, compared to education alone, in preventing excessive gestational weight gain and postpartum weight retention 12 months post birth. A secondary aim of this study is to evaluate the mechanisms by which our HC intervention impacts on weight management both during pregnancy and post birth.Methods/DesignThe randomized controlled trial will be conducted with 220 women who have a BMI &gt; 18.5 (American IOM cut-off for normal weight), are 18 years of age or older, English speaking, no history of disordered eating or diabetes and are less than 18 weeks gestation at recruitment. Women will be randomly allocated to either a specialized HC intervention group or an Education Alone group. Our specialized HC intervention has two components: (1) one-on-one sessions with a Health Coach, and (2) two by two hour educational group sessions led by a Health Coach. Women in the Education Alone group will receive two by two hour educational group sessions with no HC components. Body Mass Index, waist circumference, and psychological factors including motivation, readiness to change, symptoms of depression and anxiety, and body dissatisfaction will be assessed at baseline (14-16 weeks gestation), and again at follow-up: 32 weeks gestation, 6 weeks, 6 months and 12 months postpartum.DiscussionOur study responds to the urgent need to design effective interventions in pregnancy to prevent excessive gestational weight gain and postpartum weight retention. Our pregnancy HC intervention is novel and innovative and has been designed to be easily adopted by health professionals who work with pregnant women, such as obstetricians, midwives, allied health professionals and health psychologists. <br /

    A purple acid phosphatase from sweet potato contains an antiferromagnetically coupled binuclear Fe-Mn center

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    A purple acid phosphatase from sweet potato is the first reported example of a protein containing an enzymatically active binuclear Fe-Mn center. Multifield saturation magnetization data over a temperature range of 2 to 200 K indicates that this center is strongly antiferromagnetically coupled. Metal ion analysis shows an excess of iron over manganese. Low temperature EPR spectra reveal only resonances characteristic of high spin Fe(III) centers (Fe(III)-apo and Fe(III)-Zn(II)) and adventitious Cu(II) centers. There were no resonances from either Mn(II) or binuclear Fe-Mn centers. Together with a comparison of spectral properties and sequence homologies between known purple acid phosphatases, the enzymatic and spectroscopic data strongly indicate the presence of catalytic Fe(III)-Mn(II) centers in the active site of the sweet potato enzyme. Because of the strong antiferromagnetism it is likely that the metal ions in the sweet potato enzyme are linked via a mu -oxo bridge, in contrast to other known purple acid phosphatases in which a mu -hydroxo bridge is present. Differences in metal ion composition and bridging may affect substrate specificities leading to the biological function of different purple acid phosphatases
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