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1.
Ann Anat ; 250: 152155, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37683899

RESUMO

BACKGROUND: Mental health problems are common in medical professionals and their development already starts at the undergraduate level. Studies on medical students can replicate higher prevalence for depression and burnout in this group, but they normally compare semester cohorts in an anonymized, cross-sectional approach and without a preventive perspective. METHODS: We surveyed medical students at the beginning and end of their medical curriculum and collected data on burnout, depressivity, work related experience and salutogenesis parameters with validated self-administered questionnaires. Most remarkably we obtained the data from the same 58 individuals after 5.5 years, representing data of the highest quality in order to compare the mental health status at the beginning and the end of our students´ medical curriculum. RESULTS: Our results not only show a severe exacerbation of physical, mental and emotional burnout in the participants at the end of their studies. The students also do not seem to have sufficient personal (resilience) or social resources (e.g. experience of social support) for coping with their mental health problems around the time of their graduation. CONCLUSIONS: Our participants reflect a development of mental health during their medical studies at university that is paving the way to the devastating prevalence of mental disorders and suicide in health professionals. From our results we derive an urgent need to integrate self-care and active coping in the learning goals of medical curricula.


Assuntos
Esgotamento Profissional , Estudantes de Medicina , Humanos , Saúde Mental , Estudantes de Medicina/psicologia , Estudos Longitudinais , Adaptação Psicológica , Inquéritos e Questionários , Esgotamento Profissional/epidemiologia , Esgotamento Profissional/psicologia
2.
Acute Med ; 22(4): 209-257, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38284637

RESUMO

OBJECTIVE: To determine factors affecting inpatient sleep and assess the range and effectiveness of non-pharmacological interventions aimed at improving the sleep of patients admitted to regular care wards. METHODS: A systematic literature search was conducted in five scientific databases, including articles published from inception to June 23rd, 2023. Eligible studies evaluated sleep disturbing factors or the effect of non-pharmacological intervention(s). Meta-analyses on intervention studies were conducted using a random effects model. Certainty of evidence was assessed using the GRADE approach. RESULTS: Out of 591 potentially eligible studies, 229 were included in this review. Sleep disturbers were identified in 153 studies, and 102 studies were eligible for meta-analysis. Common factors contributing to poor sleep included noise, light, care-related interruptions, pain, and anxiety. The meta-analyses revealed large pooled effects in favor of sleep for the use of eye masks and earplugs, headphones and white noise, aromatherapy, massage, muscle relaxation and breathing exercises, and advanced nursing strategies. However, the certainty of the evidence ranged from moderate to very low. CONCLUSION: Inpatient sleep is often disturbed by patient-related, care-related, and environmental factors. While there are promising non-pharmacological interventions, the overall quality of studies, heterogeneity in study populations, and differences in outcome measures present challenges for drawing definitive conclusions.


Assuntos
Hospitais , Pacientes Internados , Humanos , Hospitalização , Sono
3.
ESMO Open ; 7(1): 100388, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35121522

RESUMO

BACKGROUND: Pulmonary metastasis (M1-PUL) as first site of dissemination in pancreatic ductal adenocarcinoma (PDAC) is a rare event and may define a distinct biological subgroup. PATIENTS AND METHODS: Arbeitsgemeinschaft Internistische Onkologie-Young Medical Oncologists-Pankreas-0515 study (AIO-YMO-PAK-0515) was a retrospective German multicenter study investigating clinical and molecular characteristics of M1-PUL PDAC patients; 115 M1-PUL PDAC patients from 7 participating centers were included. Clinical characteristics and potential prognostic factors were defined within the M1-PUL cohort. Archival tumor samples were analyzed for Her2/neu, HNF1A and KRT81 expression. Additionally, messenger RNA (mRNA) expression analysis (using a 770-gene immune profiling panel) was carried out in the M1-PUL and in a control cohort (M1-ANY). RESULTS: Median overall survival in the entire M1-PUL cohort was 20 months; the most favorable prognosis (median survival: 28 months) was observed in the subgroup of 66 PDAC patients with metachronous lung metastases after previous curative-intent surgery. The number of metastatic lesions, uni- or bilateral lung involvement as well as metastasectomy were identified as potential prognostic factors. Her2/neu expression and PDAC subtyping (by HNF1A and KRT81) did not differ between the M1-PUL and the M1-ANY cohort. mRNA expression analysis revealed significant differentially expressed genes between both cohorts: CD63 and LAMP1 were among the top 20 differentially expressed genes and were identified as potential mediators of organotropism and favorable survival outcome of M1-PUL patients. CONCLUSION: M1-PUL represents a clinically favorable cohort in PDAC patients. Site of relapse might already be predetermined at the time of surgery and could potentially be predicted by gene expression profiling.


Assuntos
Neoplasias Pulmonares , Neoplasias Pancreáticas , Biologia , Humanos , Neoplasias Pulmonares/genética , Recidiva Local de Neoplasia , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patologia , Prognóstico , Estudos Retrospectivos
4.
Resour Conserv Recycl ; 164: 105140, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32921915

RESUMO

The Trans-Atlantic Research and Development Interchange on Sustainability Workshop (TARDIS) is a meeting on scientific topics related to sustainability. The 2019 workshop theme was "On the Role of Uncertainty in Managing the Earth for Global Sustainability." This paper presents the perspectives on this topic derived from talks and discussions at the 2019 TARDIS workshop. There are four kinds of uncertainties encountered in sustainability ranging from clear enough futures to true surprises. The current state-of-the-art in assessing and mitigating these uncertainties is discussed.

5.
Trop Anim Health Prod ; 52(4): 2179-2189, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32128662

RESUMO

Cattle production is an essential livelihood strategy in south-western Burkina Faso. Although having a distinct cultural role and known to be resistant against African animal trypanosomosis, the Lobi taurine cattle breed is endangered due to its low market value. As the first step in preservation efforts, our study aimed to develop a typology of production systems at the farm level. We used a structured questionnaire and focus group discussions for collecting data on household characteristics, socioeconomic activities, livestock, and access to services. The sample comprised 169 households in three communities. The analytical strategy included factor analysis of mixed data and hierarchical clustering. We identified four distinct types of cattle production systems: (1) sedentary Lobi farms, (2) sedentary crossbreed farms, (3) semi-transhumant Fulani zebu farms, and (4) transhumant Fulani zebu farms. Significant factors in developing this typology were the farmers' ethnic group, crop diversity, cattle herd size, cattle herd composition, number of small ruminants, and livestock management strategies. Across all production systems, men were considered being primary decision-makers in cattle production, with women, herders, and children being responsible for specific tasks. All identified production systems are increasingly confronting disease pressure and scarcity of water and land. Future efforts in preservation and breeding will need to respond to these trends in the agroecosystem, integrate risk management measures, and resonate with the specific needs of the different household members involved in cattle rearing.


Assuntos
Criação de Animais Domésticos , Cruzamento , Fazendeiros , Gado , Animais , Burkina Faso , Bovinos , Características da Família , Fazendas , Feminino , Grupos Focais , Humanos , Masculino , Inquéritos e Questionários
6.
Dev Comp Immunol ; 106: 103614, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31962062

RESUMO

The emergent availability in public databases of more complete genome assemblies allows us to improve genomic data obtained by classical molecular cloning. The main goal of this study was to refine the genomic map of the dromedary TRG locus by integrating our previous genomic data with the analysis of recent genomic assemblies. We identified an additional TRGC cassette, defined as a V-J-C recombination unit, located at the 5' of the locus and made up of five TRGV genes followed by three TRGJ genes and one TRGC gene. Hence, the complete dromedary TRG locus spans about 105 Kb and consists of three in tandem TRGC cassettes delimited by AMPH and STARD3NL genes at the 5' and 3' end, respectively. An expression assay carried out on peripheral blood showed the functional competency for the dromedary TRGC5 cassette and confirmed the presence of the somatic hypermutation mechanism able to enlarge the repertoire diversity of the dromedary γδ T cells.


Assuntos
Camelus/imunologia , Loci Gênicos/genética , Receptores de Antígenos de Linfócitos T gama-delta/genética , Linfócitos T/metabolismo , Animais , Evolução Molecular , Variação Genética , Genoma , Filogenia , Recombinação Genética , Alinhamento de Sequência , Ovinos , Hipermutação Somática de Imunoglobulina
7.
Anim Genet ; 50(6): 598-612, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31532019

RESUMO

Old World camels have served humans in cross-continental caravans, transporting people and goods, connecting different cultures and providing milk, meat, wool and draught since their domestication around 3000-6000 years ago. In a world of modern transport and fast connectivity, these beasts of burden seem to be out-dated. However, a growing demand for sustainable milk and meat production, especially in countries affected by climate change and increasing desertification, brings dromedaries (Camelus dromedarius) and Bactrian camels (Camelus bactrianus) back onstage and into the focus of animal breeders and scientists. In this review on the molecular genetics of these economically important species we give an overview about the evolutionary history, domestication and dispersal of Old World camels, whereas highlighting the need for conservation of wild two-humped camels (Camelus ferus) as an evolutionarily unique and highly endangered species. We provide cutting-edge information on the current molecular resources and on-going sequencing projects. We cannot emphasise enough the importance of balancing the need for improving camel production traits with maintaining the genetic diversity in two domestic species with specific physiological adaptation to a desert environment.


Assuntos
Camelus/genética , Migração Animal , Animais , Evolução Biológica , Camelus/anatomia & histologia , Camelus/classificação , Camelus/fisiologia , Domesticação , Hibridização Genética
8.
Rev Neurol (Paris) ; 175(6): 390-395, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30736986

RESUMO

INTRODUCTION: Stroke is a public health priority in France. The use of telemedicine for stroke known as telestroke, is a safe and effective practice improving access to acute stroke care including thrombolysis. Telestroke is currently being implemented in France. The objective was to describe the public health policy supporting telestroke implementation in France. METHODS: An external ex-post evaluation of telestroke policy in France was conducted through a retrospective descriptive study from 2003 to 31st December 2016. Process, content, and actors of the health policy were described at a national level. The logical framework of the telestroke policy was described. The stages model of public policy from the 'Institut National de Santé Publique du Quebec' was used. RESULTS: Agenda setting was produced from 2003 to 2007. Policy formulation lasted from 2008 to 2009 with official reports on telemedicine, telehealth and stroke. The decision-making stage included the national stroke plan, the national telemedicine implementation strategy and an administrative document in 2012 that described the organization of telestroke implementation. Implementation in 2011 was initiated with dedicated funding and methodological resources. No dedicated evaluation of policy for telestroke was defined. CONCLUSIONS: Using a health policy model allowed to describe the policies supporting telestroke implementation in France and to highlight the need for better evaluation.


Assuntos
Fibrinolíticos/uso terapêutico , Política de Saúde , Acidente Vascular Cerebral/tratamento farmacológico , Telemedicina , Terapia Trombolítica , Cuidados Críticos/legislação & jurisprudência , Cuidados Críticos/métodos , França , Implementação de Plano de Saúde/legislação & jurisprudência , Implementação de Plano de Saúde/normas , Política de Saúde/legislação & jurisprudência , Humanos , Avaliação de Programas e Projetos de Saúde , Estudos Retrospectivos , Telemedicina/legislação & jurisprudência , Telemedicina/métodos , Terapia Trombolítica/métodos , Terapia Trombolítica/normas
9.
Ann Anat ; 218: 1-6, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29551695

RESUMO

BACKGROUND: In Germany, currently two out of three medical students are female. Several studies corroborate that medical students show a significantly higher prevalence of stress-related mental disorders than the population in general. AIMS: We aimed to evaluate, if gender has an influence on the distribution of mental stress parameters and learning style among male and female medical students. METHODS: We investigated a total of 758 students of the medical faculty at the University of Erlangen-Nuernberg, Germany, using standardized and validated psychological questionnaires on depressive symptoms (BDI-II), burnout (BOSS-II) and quality of life (SF-12). In addition, we screened the students for their learning styles according to Kolb. RESULTS: Out of 723 participants who declared their gender, 57.8% were female and 37.6% were male. Female students showed significantly higher values for depressiveness as well as for emotional and cognitive burnout, whereas the mental quality of life was significantly lower. A considerably higher percentage of male students with a converging or an accommodating learning style were found in comparison to their female fellows. CONCLUSIONS: We postulate that an adaptation of the medical curriculum content to the investigated factors may contribute to a higher mental stability and less stress-related symptoms in medical students.


Assuntos
Saúde Mental , Estudantes de Medicina/psicologia , Esgotamento Profissional/epidemiologia , Esgotamento Profissional/psicologia , Currículo , Depressão/epidemiologia , Depressão/psicologia , Feminino , Humanos , Aprendizagem , Masculino , Prevalência , Qualidade de Vida , Caracteres Sexuais , Estresse Psicológico/epidemiologia , Estresse Psicológico/psicologia , Inquéritos e Questionários , Adulto Jovem
10.
Vaccine ; 35(18): 2504-2510, 2017 04 25.
Artigo em Inglês | MEDLINE | ID: mdl-28341113

RESUMO

African horse sickness (AHS) is a fatal disease of equids relevant to the global equine industry. Detection of AHS virus (AHSV) during outbreaks has become more rapid and efficient with the advent of group specific reverse transcriptase quantitative polymerase chain reaction (GS RT-qPCR) assays to detect AHSV nucleic acid. Use of GS RT-qPCR together with recently described type specific (TS RT-qPCR) assays cannot only expedite diagnosis of AHS but also facilitate further evaluation of the dynamics of AHSV infection in the equine host. A potential limitation to the application of these assays is that they detect viral nucleic acid originating from any AHS live attenuated vaccine (LAV), which is the vaccine type routinely administered to horses in South Africa. The aim of this study was to contrast the dynamics and duration of the RNAaemia to the serological responses of horses following immunization with a commercial polyvalent AHSV-LAV using GS and TS RT-qPCR assays and serum neutralisation tests. The results of the study showed extended RNAemia in vaccinated horses, and that more horses tested positive on GS RT-qPCR with lower Cq values after receiving the AHSV-LAV containing types 1, 3 and 4 prior to the vaccine containing types 2, 6, 7 and 8, rather than when the vaccine combinations were reversed. Furthermore, lower Cq values were obtained when vaccines were administered 4weeks apart as compared with a longer interval or 12weeks apart. These findings are of particular relevance in regions where AHSV-LAVs are used as the use of these vaccines may complicate the accurate interpretation of diagnostic testing results.


Assuntos
Vírus da Doença Equina Africana/imunologia , Vírus da Doença Equina Africana/isolamento & purificação , Doença Equina Africana/prevenção & controle , Anticorpos Antivirais/sangue , RNA Viral/sangue , Vacinas Virais/administração & dosagem , Animais , Anticorpos Neutralizantes/sangue , Cavalos , Imunização , Testes de Neutralização , Reação em Cadeia da Polimerase em Tempo Real , África do Sul , Vacinas Atenuadas/administração & dosagem
11.
Ann Anat ; 208: 183-186, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27381948

RESUMO

PURPOSE: Early intervention to counter mental disorders during the course of studies in dentistry is indicated in view of the pronounced prevalence of burnout in this student collective. To assess the proportion of students in whom these risk states can be quantified in measurable parameters for concrete mental disorders, we conducted surveys among students of dental medicine during the first 2.5 years of their studies. METHODS: We surveyed a total of 163 students of dental medicine in their first 5 semesters of study. Standardized, validated psychological questionnaires on depressive symptoms (Beck Depression Inventory; BDI-II) and mental and physical quality of life (Short Form Survey; SF-12) were used in the survey, with per-semester participant quotas of around 90%. RESULTS: Regarding depression, the students were within the range of the normal populace at the beginning of the 1st semester. Symptoms of depression then became more pronounced with every succeeding semester. In the fifth semester, the average levels determined were equivalent to a depression with a clinical treatment indication. Hardly any change was registered for physical wellbeing in the quality of life questionnaire. The mental sum scores, however, reflected dramatic downturns in quality of life. Highly significant correlations between the parameters described here - depressivity and mental quality of life - were observed in all semesters. CONCLUSION: The participating students begin their course of studies at the level of the average populace for the symptoms surveyed, then develop, on average, a clinically manifest depression after 2.5 years. The personal experience of a deterioration of mental quality of life appears to be crucial in the phenomena observed.


Assuntos
Depressão/epidemiologia , Depressão/psicologia , Educação em Odontologia/estatística & dados numéricos , Qualidade de Vida/psicologia , Estudantes de Odontologia/psicologia , Estudantes de Odontologia/estatística & dados numéricos , Adolescente , Adulto , Esgotamento Profissional/epidemiologia , Esgotamento Profissional/psicologia , Feminino , Alemanha/epidemiologia , Humanos , Masculino , Prevalência , Fatores de Risco , Adulto Jovem
12.
Ann Anat ; 208: 204-207, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27349937

RESUMO

PURPOSE: We investigated mental risk factors such as symptoms of burnout and sense of coherence in students of dental medicine at the University of Erlangen in the context of a learning type survey. Our aim was to assess the presence of analogies to the results we had previously determined for students of human medicine. METHODS: We surveyed a total of 163 dentistry students during the first 2.5 years, up to the first state examination. To ensure comparability, the data were collected from all students at the beginning of each semester. Standardized, validated questionnaires on burnout symptoms (Burnout Screening Scales; BOSS-II), sense of coherence (Sense of Coherence Scale; SOC-L9) and learning type according to Kolb were used in the survey. RESULTS: A total of about 90% of the students provided responses to the voluntary survey. The extent and manifest dynamics of the stress levels observed can be characterized as dramatic. Having started out at cognitive and emotional stress levels typical of the normal populace, a massive deterioration of these parameters was observed in the students by the time they were facing their first state examination in the 5th semester. At the same time, their sense of coherence also suffered a pronounced drop-off. No significant learning type-correlated differences were determined in a mean comparison of the measured parameters. CONCLUSION: Based on the results obtained, we see a need for preventive course offerings to students of dentistry to reduce the prevalence of mental disorders in this group. We discern additional potential for enhancement of mental health with courses more specifically geared to the different learning styles among the students.


Assuntos
Esgotamento Profissional/epidemiologia , Esgotamento Profissional/psicologia , Educação em Odontologia/estatística & dados numéricos , Transtornos Mentais/epidemiologia , Transtornos Mentais/psicologia , Estudantes de Odontologia/psicologia , Adolescente , Adulto , Distribuição por Idade , Inquéritos de Saúde Bucal , Feminino , Alemanha/epidemiologia , Humanos , Incidência , Masculino , Fatores de Risco , Distribuição por Sexo , Estudantes de Odontologia/estatística & dados numéricos , Adulto Jovem
13.
J Thromb Haemost ; 13(4): 651-9, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25529050

RESUMO

BACKGROUND: Single nucleotide polymorphisms (SNPs) in platelet-associated genes partly explain inherent variability in platelet counts. Patients with monoallelic Bernard Soulier syndrome due to the Bolzano mutation (GPIBA A156V) have variable platelet counts despite a common mutation for unknown reasons. OBJECTIVES: We investigated the effect of the most common SNP (R307H) in the hematopoietic-specific tubulin isotype ß-1 in these Bernard Soulier patients and potential microtubule-based mechanisms of worsened thrombocytopenia. PATIENTS/METHODS: Ninety-four monoallelic Bolzano mutation patients were evaluated for the R307H ß-1 SNP and had platelet counts measured by three methods; the Q43P SNP was also evaluated. To investigate possible mechanisms underlying this association, we used molecular modeling of ß-1 tubulin with and without the R307H SNP. We transfected SNP or non-SNP ß-1 tubulin into MCF-7 and CMK cell lines and measured microtubule regrowth after nocodazole-induced depolymerization. RESULTS: We found that patients with at least one R307H SNP allele had significantly worse thrombocytopenia; manual platelet counting revealed a median platelet count of 124 in non-SNP patients and 76 in SNP patients (both ×10(9)  L(-1) ; P < 0.01). The Q43P SNP had no significant association with platelet count. Molecular modeling suggested a structural relationship between the R307H SNP and microtubule stability via alterations in the M-loop of ß tubulin; in vitro microtubule recovery assays revealed that cells transfected with R307H SNP ß-1 had significantly impaired microtubule recovery. CONCLUSIONS: Our data show that the R307H SNP is significantly associated with the degree of thrombocytopenia in congenital and acquired platelet disorders, and may affect platelets by altering microtubule behavior.


Assuntos
Síndrome de Bernard-Soulier/genética , Plaquetas/metabolismo , Microtúbulos/metabolismo , Polimorfismo de Nucleotídeo Único , Tubulina (Proteína)/genética , Tubulina (Proteína)/metabolismo , Síndrome de Bernard-Soulier/sangue , Síndrome de Bernard-Soulier/diagnóstico , Plaquetas/efeitos dos fármacos , Cristalografia por Raios X , Marcadores Genéticos , Predisposição Genética para Doença , Humanos , Células MCF-7 , Microtúbulos/efeitos dos fármacos , Modelos Moleculares , Fenótipo , Contagem de Plaquetas , Conformação Proteica , Estabilidade Proteica , Índice de Gravidade de Doença , Relação Estrutura-Atividade , Transfecção , Tubulina (Proteína)/química , Moduladores de Tubulina/farmacologia
14.
Environ Manage ; 54(5): 935-50, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25156863

RESUMO

It has become increasingly clear that desertification can only be tackled through a multi-disciplinary approach that not only involves scientists but also stakeholders. In the DESIRE project such an approach was taken. As a first step, a conceptual framework was developed in which the factors and processes that may lead to land degradation and desertification were described. Many of these factors do not work independently, but can reinforce or weaken one another, and to illustrate these relationships sustainable management and policy feedback loops were included. This conceptual framework can be applied globally, but can also be made site-specific to take into account that each study site has a unique combination of bio-physical, socio-economic and political conditions. Once the conceptual framework was defined, a methodological framework was developed in which the methodological steps taken in the DESIRE approach were listed and their logic and sequence were explained. The last step was to develop a concrete working plan to put the project into action, involving stakeholders throughout the process. This series of steps, in full or in part, offers explicit guidance for other organizations or projects that aim to reduce land degradation and desertification.


Assuntos
Recuperação e Remediação Ambiental/métodos , Modelos Teóricos , Desenvolvimento de Programas , Política Pública , Clima Desértico , Recuperação e Remediação Ambiental/tendências , Humanos
15.
Anim Genet ; 45(4): 550-8, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24749721

RESUMO

The tradition of animal husbandry in the context of a nomadic lifestyle has been of great significance in the Mongolian society. Both Bactrian camels and horses have been invaluable for the survival and development of human activities in the harsh arid environment of the Mongolian steppe. As camels offer unique and sustainable opportunities for livestock production in marginal agro-ecological zones, we investigated the current genetic diversity of three local Mongolian camel breeds and compared their levels of variation with common native Mongolian camels distributed throughout the country. Based on mitochondrial and nuclear markers, we found levels of genetic diversity in Mongolian populations similar to that reported for Chinese Bactrian camels and for dromedaries. Little differentiation was detected between single breeds, except for a small group originating from the northwestern Mongolian Altai. We found neither high inbreeding levels in the different breeds nor evidence for a population decline. Although the Mongolian camel census size has severely declined over the past 20 years, our analyses suggest that there still exists a stable population with adequate genetic variation for continued sustainable utilization.


Assuntos
Camelus/genética , Variação Genética , Animais , Núcleo Celular/genética , DNA Mitocondrial/genética , Dados de Sequência Molecular , Mongólia , Reação em Cadeia da Polimerase/veterinária , Análise de Sequência de DNA/veterinária
16.
Phys Rev Lett ; 112(4): 047001, 2014 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-24580480

RESUMO

The nematic susceptibility, χφ, of hole-doped Ba(1-x)K(x)Fe2As2 and electron-doped Ba(Fe(1-x)Co(x))2As2 iron-based superconductors is obtained from measurements of the elastic shear modulus using a three-point bending setup in a capacitance dilatometer. Nematic fluctuations, although weakened by doping, extend over the whole superconducting dome in both systems, suggesting their close tie to superconductivity. Evidence for quantum critical behavior of χφ is, surprisingly, only found for Ba(Fe(1-x)Co(x))2As2 and not for Ba(1-x)K(x)Fe2As2--the system with the higher maximal Tc value.

17.
Phys Rev Lett ; 111(2): 027002, 2013 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-23889432

RESUMO

Using resistivity, heat-capacity, thermal-expansion, and susceptibility measurements we study the normal-state behavior of KFe2As2. Both the Sommerfeld coefficient (γ≈103 mJ mol(-1) K(-2)) and the Pauli susceptibility (χ≈4×10(-4)) are strongly enhanced, which confirm the existence of heavy quasiparticles inferred from previous de Haas-van Alphen and angle-resolved photoemission spectroscopy experiments. We discuss this large enhancement using a Gutzwiller slave-boson mean-field calculation, which shows the proximity of KFe2As2 to an orbital-selective Mott transition. The temperature dependence of the magnetic susceptibility and the thermal expansion provide strong experimental evidence for the existence of a coherence-incoherence crossover, similar to what is found in heavy fermion and ruthenate compounds, due to Hund's coupling between orbitals.

18.
Fortschr Neurol Psychiatr ; 80(6): 320-6, 2012 Jun.
Artigo em Alemão | MEDLINE | ID: mdl-22173965

RESUMO

In the field of adult psychiatry in German-speaking countries, little attention is as yet paid to the psychic defects that a fetus can sustain as a result of prenatal exposure to alcohol. Although children of alcohol-dependent mothers do present to psychiatric institutions as adults with manifold symptoms, e. g., attention deficit disorders, affective disorders or intellectual disability, fetal alcohol spectrum disorders are rarely diagnosed as an underlying cause. Appropriate therapy guidelines do not exist. Current review papers within the German-speaking countries usually stem from paediatric and adolescent psychiatry or medicine. Based on a selected review of the literature, the following paper addresses and discusses the disease entity of fetal alcohol spectrum disorders and fetal alcohol syndrome and their significance for adult psychiatry and also identifies open questions and research requirements, e. g., the development of diagnostic instruments or the establishment of diagnostic categories.


Assuntos
Transtornos do Espectro Alcoólico Fetal/psicologia , Efeitos Tardios da Exposição Pré-Natal/psicologia , Anormalidades Induzidas por Medicamentos/psicologia , Adolescente , Adulto , Sintomas Afetivos/etiologia , Sintomas Afetivos/psicologia , Transtorno do Deficit de Atenção com Hiperatividade/etiologia , Transtorno do Deficit de Atenção com Hiperatividade/psicologia , Feminino , Transtornos do Espectro Alcoólico Fetal/epidemiologia , Transtornos do Espectro Alcoólico Fetal/terapia , Alemanha/epidemiologia , Humanos , Doenças do Sistema Nervoso/induzido quimicamente , Doenças do Sistema Nervoso/congênito , Gravidez , Efeitos Tardios da Exposição Pré-Natal/epidemiologia , Efeitos Tardios da Exposição Pré-Natal/terapia , Escalas de Graduação Psiquiátrica , Fatores de Risco
20.
Fortschr Neurol Psychiatr ; 79(9): 500-6, 2011 Sep.
Artigo em Alemão | MEDLINE | ID: mdl-21739408

RESUMO

Besides genetic susceptibility, environmental factors and gene-environment interactions are of central interest in research on attention deficit/hyperactivity disorder in children. Focusing on maternal behaviour during pregnancy, prenatal maternal alcohol consumption is associated with behavioural disorders in children. In animal models, developmental disorders of brain structures as well as subsequent behavioural disorders - similar to findings in attention deficit disorder - were caused by prenatal alcohol exposure. These findings occur in small rodents (mice, rats) as well as in primates and can be caused by even moderate alcohol exposure. In foetal alcohol syndrome (FAS) and foetal alcohol spectrum disease (FASD) in humans, symptoms like hyperactivity, disruptive or impulsive behaviour along with reduced attention and slower reaction time are observed. These findings resemble the symptoms of ADHD. For that reason, children diagnosed with FAS/FASD are frequently diagnosed with ADHD in parallel. Even small amounts of alcohol during pregnancy are responsible for cognitive and behavioural impairments like a significantly decreased IQ. About 50 % of adult ADHD patients show alcohol abuse or dependency and/or other substance disorders. Due to this, a higher rate of prenatal exposition to psychoactive substances for children of mothers affected with ADHD seems probable. However, there are no sufficient data on ADHD and its association to substance abuse in pregnancy, which makes it difficult to quantify the impact of genetic and environmental causes for the development of childhood ADHD. So far, no link could be proven with a high level of evidence between moderate prenatal alcohol consumption and the development of childhood ADHD. It has to be recognised that all present studies are based on self-reported alcohol consumption. Data collected by this methodology are usually severely biased to an underestimation of alcohol abuse. Objective tests for alcohol abuse in pregnancy, such as the analysis of fatty acid ethyl esters or ethyl glucuronide in foetal feces after birth, show rates of alcohol consumption in pregnant women which are dramatically higher than reported. Therefore, studies investigating the association between prenatal alcohol exposure and ADHD should incorporate the analysis and validation of more objective methods, such as parameters for alcohol degradation.


Assuntos
Consumo de Bebidas Alcoólicas/efeitos adversos , Transtorno do Deficit de Atenção com Hiperatividade/etiologia , Gravidez/fisiologia , Adulto , Consumo de Bebidas Alcoólicas/epidemiologia , Transtorno do Deficit de Atenção com Hiperatividade/epidemiologia , Transtorno do Deficit de Atenção com Hiperatividade/genética , Transtorno do Deficit de Atenção com Hiperatividade/fisiopatologia , Depressores do Sistema Nervoso Central/efeitos adversos , Criança , Etanol/efeitos adversos , Feminino , Interação Gene-Ambiente , Humanos , Recém-Nascido , Transtornos Relacionados ao Uso de Substâncias/complicações
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