Neutron cryo-crystallography captures the protonation state of ferryl heme in a peroxidase

Heme enzymes activate oxygen through formation of transient iron-oxo (ferryl) intermediates of the heme iron. A long-standing question has been the nature of the iron-oxygen bond and, in particular, the protonation state. We present neutron structures of the ferric derivative of cytochrome c peroxidase and its ferryl intermediate; these allow direct visualization of protonation states. We demonstrate that the ferryl heme is an Fe(IV)=O species and is not protonated. Comparison of the structures shows that the distal histidine becomes protonated on formation of the ferryl intermediate, which has implications for the understanding of O–O bond cleavage in heme enzymes. The structures highlight the advantages of neutron cryo-crystallography in probing reaction mechanisms and visualizing protonation states in enzyme intermediates

Genetic educational needs and the role of genetics in primary care: a focus group study with multiple perspectives

Contains fulltext : 96953.pdf (publisher's version ) (Open Access)BACKGROUND: Available evidence suggests that improvements in genetics education are needed to prepare primary care providers for the impact of ongoing rapid advances in genomics. Postgraduate (physician training) and master (midwifery training) programmes in primary care and public health are failing to meet these perceived educational needs. The aim of this study was to explore the role of genetics in primary care (i.e. family medicine and midwifery care) and the need for education in this area as perceived by primary care providers, patient advocacy groups and clinical genetics professionals. METHODS: Forty-four participants took part in three types of focus groups: mono-disciplinary groups of general practitioners and midwives, respectively and multidisciplinary groups composed of a diverse set of experts. The focus group sessions were audio-taped, transcribed verbatim and analysed using content analysis. Recurrent themes were identified. RESULTS: Four themes emerged regarding the educational needs and the role of genetics in primary care: (1) genetics knowledge, (2) family history, (3) ethical dilemmas and psychosocial effects in relation to genetics and (4) insight into the organisation and role of clinical genetics services. These themes reflect a shift in the role of genetics in primary care with implications for education. Although all focus group participants acknowledged the importance of genetics education, general practitioners felt this need more urgently than midwives and more strongly emphasized their perceived knowledge deficiencies. CONCLUSION: The responsibilities of primary care providers with regard to genetics require further study. The results of this study will help to develop effective genetics education strategies to improve primary care providers' competencies in this area. More research into the educational priorities in genetics is needed to design courses that are suitable for postgraduate and master programmes for general practitioners and midwives

Decision making and experiences of young adults undergoing presymptomatic genetic testing for familial cancer: A longitudinal grounded theory study

Enabling informed choice is an essential component of care when offering young adults presymptomatic testing for a genetic condition. A systematic review on this topic revealed that many young adults grew up with little information regarding their genetic risk and that parents had applied pressure to them during the testing decision-making process. However, none of the studies retrieved were conducted in South European countries. To address this gap, we undertook a qualitative study based on grounded theory to explore the psychosocial implications of presymptomatic testing for hereditary cancer in Italian young adults aged 18-30 years. Interviews were conducted on three occasions: 1 month before counselling, and 2 weeks and 6 months after results. Data were coded and grouped under themes. A total of 42 interviews were conducted. Four themes emerged: knowledge, genetic counselling process, decision making and dealing with test results. Although participants grew up with little or no information about their genetic risk, none expressed regret at having the test at a young age. Pre-test counselling was appreciated as a source of information, rather than support for decision making. Decisions were often made autonomously and sometimes conflicted with parents' wishes. Participants reported no changes in health behaviours after testing. This evidence highlights the need for a comprehensive, longitudinal counselling process with appropriate timing and setting, which supports 'parent-to-offspring' risk communication first and decision making by young adults about presymptomatic testing and risk management afterwards. In conclusion, it is clear that counselling approaches for presymptomatic testing may require modification both for young adults and their parents. © 2017 European Society of Human Genetics

How communication of genetic information within the family is addressed in genetic counselling: a systematic review of research evidence

Supporting consultands to communicate risk information with their relatives is key to obtaining the full benefits of genetic health care. To understand how health-care professionals address this issue in clinical practice and what interventions are used specifically to assist consultands in their communication of genetic information to appropriate relatives, we conducted a systematic review. Four electronic databases and four subject-specific journals were searched for papers published, in English, between January 1997 and May 2014. Of 2926 papers identified initially, 14 papers met the inclusion criteria for the review and were heterogeneous in design, setting and methods. Thematic data analysis has shown that dissemination of information within families is actively encouraged and supported by professionals. Three overarching themes emerged: (1) direct contact from genetic services: sending letters to relatives of mutation carriers; (2) professionals' encouragement of initially reluctant consultands to share relevant information with at-risk relatives and (3) assisting consultands in communicating genetic information to their at-risk relatives, which included as subthemes (i) psychoeducational guidance and (ii) written information aids. Findings suggest that professionals' practice and interventions are predicated on the need to proactively encourage family communication. We discuss this in the context of what guidance of consultands by professionals might be appropriate, as best practices to facilitate family communication, and of the limits to non-directiveness in genetic counselling

Interaction among general practitioners age and patient load in the prediction of job strain, decision latitude and perception of job demands. A Cross-sectional study

BACKGROUND: It is widely recognized and accepted that job strain adversely impacts the workforce. Individual responses to stressful situations can vary greatly and it has been shown that certain people are more likely to experience high levels of stress in their job than others. Studies highlighted that there can be age differences in job strain perception. METHODS: Cross-sectional postal survey of 300 Lithuanian general practitioners. Psychosocial stress was investigated with a questionnaire based on the Reeder scale. Job demands were investigated with the Karasek scale. The analysis included descriptive statistics; logistic regression beta coefficients to find out predictors and interactions between characteristics and predictors. RESULTS: Response rate was 66% (N = 197). Logistic regression as significant predictors for job strain assigned – duration of work in primary care; for job demands- age and duration of working in primary care; for decision latitude- age and patient load. The interactions with regard to job strain showed that GP's age and job strain are negatively associated to a low patient load. Lower decision latitude for older GP age is strongly related to higher patient load. Job demands and GP age are slightly positively related at low patient load. CONCLUSIONS: Lithuanian GP's have high patient load and are at risk of stress, they have high job demands and low decision latitude. Older GP's perceive less strain, lower job demands and higher decision latitude in case of low patient load. Young GP's decision latitude has week association to patient load. Regarding to the changes in patient load younger GP's perceive it more sensitively as changes in job demands

Variability of Intensive Care Admission Decisions for the Very Elderly

Although increasing numbers of very elderly patients are requiring intensive care, few large sample studies have investigated ICU admission of very elderly patients. Data on pre triage by physicians from other specialities is limited. This observational cohort study aims at examining inter-hospital variability of ICU admission rates and its association with patients' outcomes. All patients over 80 years possibly qualifying for ICU admission who presented to the emergency departments (ED) of 15 hospitals in the Paris (France) area during a one-year period were prospectively included in the study. Main outcome measures were ICU eligibility, as assessed by the ED and ICU physicians; in-hospital mortality; and vital and functional status 6 months after the ED visit. 2646 patients (median age 86; interquartile range 83–91) were included in the study. 94% of participants completed follow-up (n = 2495). 12.4% (n = 329) of participants were deemed eligible for ICU admission by ED physicians and intensivists. The overall in-hospital and 6-month mortality rates were respectively 27.2% (n = 717) and 50.7% (n = 1264). At six months, 57.5% (n = 1433) of patients had died or had a functional deterioration. Rates of patients deemed eligible for ICU admission ranged from 5.6% to 38.8% across the participating centers, and this variability persisted after adjustment for patients' characteristics. Despite this variability, we found no association between level of ICU eligibility and either in-hospital death or six-month death or functional deterioration. In France, the likelihood that a very elderly person will be admitted to an ICU varies widely from one hospital to another. Influence of intensive care admission on patients' outcome remains unclear

Presymptomatic genetic testing for hereditary cancer in young adults: a survey of young adults and parents

Presymptomatic testing for hereditary cancer syndromes should involve a considered choice. This may be particularly challenging when testing is undertaken in early adulthood. With the aim of exploring the psychosocial implications of presymptomatic testing for hereditary cancer in young adults and their parents, a cross-sectional survey was designed. Two questionnaires were developed (one for young adults who had considered presymptomatic testing, one for parents). Questionnaires were completed by 152 (65.2%) young adults and 42 (73.7%) parents. Data were analysed using descriptive statistics, inferential testing, and exploratory factor analysis and linear regression analysis. Young adults were told about their potential genetic risk at a mean age of 20 years; in most cases, information was given by a parent, often in an unplanned conversation. Although testing requests were usually made by young adults, the majority of parents felt they had control over the young adult’s decision and all felt their children should be tested. Results suggest that some young adults did not understand the implications of the genetic test but complied with parental pressure. Counselling approaches for presymptomatic testing may require modification both for young adults and their parents. Those offering testing need to be aware of the complex pressures that young adults can experience, which can influence their autonomous choices. It is therefore important to emphasise to both parents and young adults that, although testing can bring benefits in terms of surveillance and prevention, young adults have a choice

Evolutionary and pulsational properties of white dwarf stars

Abridged. White dwarf stars are the final evolutionary stage of the vast majority of stars, including our Sun. The study of white dwarfs has potential applications to different fields of astrophysics. In particular, they can be used as independent reliable cosmic clocks, and can also provide valuable information about the fundamental parameters of a wide variety of stellar populations, like our Galaxy and open and globular clusters. In addition, the high densities and temperatures characterizing white dwarfs allow to use these stars as cosmic laboratories for studying physical processes under extreme conditions that cannot be achieved in terrestrial laboratories. They can be used to constrain fundamental properties of elementary particles such as axions and neutrinos, and to study problems related to the variation of fundamental constants. In this work, we review the essentials of the physics of white dwarf stars. Special emphasis is placed on the physical processes that lead to the formation of white dwarfs as well as on the different energy sources and processes responsible for chemical abundance changes that occur along their evolution. Moreover, in the course of their lives, white dwarfs cross different pulsational instability strips. The existence of these instability strips provides astronomers with an unique opportunity to peer into their internal structure that would otherwise remain hidden from observers. We will show that this allows to measure with unprecedented precision the stellar masses and to infer their envelope thicknesses, to probe the core chemical stratification, and to detect rotation rates and magnetic fields. Consequently, in this work, we also review the pulsational properties of white dwarfs and the most recent applications of white dwarf asteroseismology.Comment: 85 pages, 28 figures. To be published in The Astronomy and Astrophysics Revie