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Language impairments caused by stroke (post-stroke aphasia, PSA) and neurodegeneration (primary progressive aphasia, PPA) have overlapping symptomatology, nomenclature and are classically divided into categorical subtypes. Surprisingly, PPA and PSA have rarely been directly compared in detail. Rather, previous studies have compared certain subtypes (e.g. semantic variants) or have focused on a specific cognitive/linguistic task (e.g. reading). This study assessed a large range of linguistic and cognitive tasks across the full spectra of PSA and PPA. We applied varimax-rotated principal component analysis to explore the underlying structure of the variance in the assessment scores. Similar phonological, semantic and fluency-related components were found for PSA and PPA. A combined principal component analysis across the two aetiologies revealed graded intra- and intergroup variations on all four extracted components. Classification analysis was used to test, formally, whether there were any categorical boundaries for any subtypes of PPA or PSA. Semantic dementia formed a true diagnostic category (i.e. within group homogeneity and distinct between-group differences), whereas there was considerable overlap and graded variations within and between other subtypes of PPA and PSA. These results suggest that (i) a multidimensional rather than categorical classification system may be a better conceptualization of aphasia from both causes; and (ii) despite the very different types of pathology, these broad classes of aphasia have considerable features in common.
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Afasia Primária Progressiva/diagnóstico , Afasia Primária Progressiva/psicologia , Análise de Componente Principal/métodos , Semântica , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/psicologia , Idoso , Afasia Primária Progressiva/etiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Fonética , Acidente Vascular Cerebral/complicaçõesRESUMO
Extinction risk has been linked to biological and anthropogenic variables. Prediction of extinction risk in valuable fauna may not follow mainstream drivers when species are exploited for international markets. We use results from an International Union for Conservation of Nature Red List assessment of extinction risk in all 377 known species of sea cucumber within the order Aspidochirotida, many of which are exploited worldwide as luxury seafood for Asian markets. Extinction risk was primarily driven by high market value, compounded by accessibility and familiarity (well known) in the marketplace. Extinction risk in marine animals often relates closely to body size and small geographical range but our study shows a clear exception. Conservation must not lose sight of common species, especially those of high value. Greater human population density and poorer economies in the geographical ranges of endangered species illustrate that anthropogenic variables can also predict extinction risks in marine animals. Local-level regulatory measures must prevent opportunistic exploitation of high-value species. Trade agreements, for example CITES, may aid conservation but will depend on international technical support to low-income tropical countries. The high proportion of data deficient species also stresses a need for research on the ecology and population demographics of unglamorous invertebrates.
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Conservação dos Recursos Naturais/estatística & dados numéricos , Espécies em Perigo de Extinção , Extinção Biológica , Pepinos-do-Mar/fisiologia , Alimentos Marinhos/estatística & dados numéricos , Análise de Variância , Animais , Pesqueiros/estatística & dados numéricos , Oceanos e Mares , Alimentos Marinhos/economiaRESUMO
Dust can affect the radiative balance of the atmosphere by absorbing or reflecting incoming solar radiation; it can also be a source of micronutrients, such as iron, to the ocean. It has been suggested that production, transport and deposition of dust is influenced by climatic changes on glacial-interglacial timescales. Here we present a high-resolution record of aeolian dust from the EPICA Dome C ice core in East Antarctica, which provides an undisturbed climate sequence over the past eight climatic cycles. We find that there is a significant correlation between dust flux and temperature records during glacial periods that is absent during interglacial periods. Our data suggest that dust flux is increasingly correlated with Antarctic temperature as the climate becomes colder. We interpret this as progressive coupling of the climates of Antarctic and lower latitudes. Limited changes in glacial-interglacial atmospheric transport time suggest that the sources and lifetime of dust are the main factors controlling the high glacial dust input. We propose that the observed approximately 25-fold increase in glacial dust flux over all eight glacial periods can be attributed to a strengthening of South American dust sources, together with a longer lifetime for atmospheric dust particles in the upper troposphere resulting from a reduced hydrological cycle during the ice ages.
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BACKGROUND AND OBJECTIVES: Alzheimer disease (AD) spans heterogeneous typical and atypical phenotypes. Posterior cortical atrophy (PCA) is a striking example, characterized by prominent impairment in visual and other posterior functions in contrast to typical, amnestic AD. The primary study objective was to establish how the similarities and differences of cognition and brain volumes within AD and PCA (and by extension other AD variants) can be conceptualized as systematic variations across a transdiagnostic, graded multidimensional space. METHODS: This was a cross-sectional, single-center, observational, cohort study performed at the National Hospital for Neurology & Neurosurgery, London, United Kingdom. Data were collected from a cohort of patients with PCA and AD, matched for age, disease duration, and Mini-Mental State Examination (MMSE) scores. There were 2 sets of outcome measures: (1) scores on a neuropsychological battery containing 22 tests spanning visuoperceptual and visuospatial processing, episodic memory, language, executive functions, calculation, and visuospatial processing and (2) measures extracted from high-resolution T1-weighted volumetric MRI scans. Principal component analysis was used to extract the transdiagnostic dimensions of phenotypical variation from the detailed neuropsychological data. Voxel-based morphometry was used to examine associations between the PCA-derived clinical phenotypes and the structural measures. RESULTS: We enrolled 93 participants with PCA (mean: age = 59.9 years, MMSE = 21.2; 59/93 female) and 58 AD participants (mean: age = 57.1 years, MMSE = 19.7; 22/58 female). The principal component analysis for PCA (sample adequacy confirmed: Kaiser-Meyer-Olkin = 0.865) extracted 3 dimensions accounting for 61.0% of variance in patients' performance, reflecting general cognitive impairment, visuoperceptual deficits, and visuospatial impairments. Plotting AD cases into the PCA-derived multidimensional space, and vice versa, revealed graded, overlapping variations between cases along these dimensions, with no evidence for categorical-like patient clustering. Similarly, the relationship between brain volumes and scores on the extracted dimensions was overlapping for PCA and AD cases. DISCUSSION: These results provide evidence supporting a reconceptualization of clinical and radiologic variation in these heterogenous AD phenotypes as being along shared phenotypic continua spanning PCA and AD, arising from systematic graded variations within a transdiagnostic, multidimensional neurocognitive geometry.
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Doença de Alzheimer , Atrofia , Imageamento por Ressonância Magnética , Testes Neuropsicológicos , Humanos , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/patologia , Feminino , Masculino , Atrofia/patologia , Idoso , Estudos Transversais , Pessoa de Meia-Idade , Córtex Cerebral/diagnóstico por imagem , Córtex Cerebral/patologia , Estudos de CoortesRESUMO
MSUD and PKU require lifetime management hence, regular monitoring of amino acid levels is needed to achieve good metabolic control. Ideally, plasma amino acid analysis (PLAA) is used to monitor concentrations but is expensive and not widely available in local laboratories. The newborn screening program in the Philippines uses dried blood spot (DBS) analysis as an alternative where only trained healthcare providers are allowed to perform the collection at selected facilities. With the increasing number of patients, DBS monitoring has been noted to be delayed due to multiple factors. This issue became even more evident during the COVID-19 pandemic where high-risk patients need to travel outside for blood collection. The study used a cross-sectional study design to determine the primary caregivers' perspective on DBS self-sampling for patients with MSUD and PKU and the acceptability of the samples collected. This was done through a series of collection training, pre-/post- surveys, and 10-item questionnaire, and an in-depth 1-on-1 interview for thematic analysis. The acceptability of samples was processed and evaluated by the newborn screening laboratory. At-home DBS collection by primary caregivers was found to be acceptable. The provision of knowledge and routine collection training by the medical team aids in the increase of sample acceptability as well as a source of empowerment in being equipped to take care of their child. It is highly recommended that DBS samples collected by caregivers be considered acceptable for more time and cost-saving monitoring of the patients' metabolites. This practice also promotes timely and appropriate management which can lead to better patient health outcomes.
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BACKGROUND: Clinical variants of primary progressive aphasia (PPA) are diagnosed based on characteristic patterns of language deficits, supported by corresponding neural changes on brain imaging. However, there is (i) considerable phenotypic variability within and between each diagnostic category with partially overlapping profiles of language performance between variants and (ii) accompanying non-linguistic cognitive impairments that may be independent of aphasia magnitude and disease severity. The neurobiological basis of this cognitive-linguistic heterogeneity remains unclear. Understanding the relationship between these variables would improve PPA clinical/research characterisation and strengthen clinical trial and symptomatic treatment design. We address these knowledge gaps using a data-driven transdiagnostic approach to chart cognitive-linguistic differences and their associations with grey/white matter degeneration across multiple PPA variants. METHODS: Forty-seven patients (13 semantic, 15 non-fluent, and 19 logopenic variant PPA) underwent assessment of general cognition, errors on language performance, and structural and diffusion magnetic resonance imaging to index whole-brain grey and white matter changes. Behavioural data were entered into varimax-rotated principal component analyses to derive orthogonal dimensions explaining the majority of cognitive variance. To uncover neural correlates of cognitive heterogeneity, derived components were used as covariates in neuroimaging analyses of grey matter (voxel-based morphometry) and white matter (network-based statistics of structural connectomes). RESULTS: Four behavioural components emerged: general cognition, semantic memory, working memory, and motor speech/phonology. Performance patterns on the latter three principal components were in keeping with each variant's characteristic profile, but with a spectrum rather than categorical distribution across the cohort. General cognitive changes were most marked in logopenic variant PPA. Regardless of clinical diagnosis, general cognitive impairment was associated with inferior/posterior parietal grey/white matter involvement, semantic memory deficits with bilateral anterior temporal grey/white matter changes, working memory impairment with temporoparietal and frontostriatal grey/white matter involvement, and motor speech/phonology deficits with inferior/middle frontal grey matter alterations. CONCLUSIONS: Cognitive-linguistic heterogeneity in PPA closely relates to individual-level variations on multiple behavioural dimensions and grey/white matter degeneration of regions within and beyond the language network. We further show that employment of transdiagnostic approaches may help to understand clinical symptom boundaries and reveal clinical and neural profiles that are shared across categorically defined variants of PPA.
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Afasia Primária Progressiva , Humanos , Afasia Primária Progressiva/diagnóstico por imagem , Afasia Primária Progressiva/patologia , Imageamento por Ressonância Magnética , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Cognição , LinguísticaRESUMO
Sea ice and dust flux increased greatly in the Southern Ocean during the last glacial period. Palaeorecords provide contradictory evidence about marine productivity in this region, but beyond one glacial cycle, data were sparse. Here we present continuous chemical proxy data spanning the last eight glacial cycles (740,000 years) from the Dome C Antarctic ice core. These data constrain winter sea-ice extent in the Indian Ocean, Southern Ocean biogenic productivity and Patagonian climatic conditions. We found that maximum sea-ice extent is closely tied to Antarctic temperature on multi-millennial timescales, but less so on shorter timescales. Biological dimethylsulphide emissions south of the polar front seem to have changed little with climate, suggesting that sulphur compounds were not active in climate regulation. We observe large glacial-interglacial contrasts in iron deposition, which we infer reflects strongly changing Patagonian conditions. During glacial terminations, changes in Patagonia apparently preceded sea-ice reduction, indicating that multiple mechanisms may be responsible for different phases of CO2 increase during glacial terminations. We observe no changes in internal climatic feedbacks that could have caused the change in amplitude of Antarctic temperature variations observed 440,000 years ago.
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Meio Ambiente , Gelo , Ferro , Cálcio/análise , Clima , Ferro/análise , Biologia Marinha , Mesilatos/análise , Oceanos e Mares , Periodicidade , Sódio/análise , América do SulRESUMO
There are few available methods for qualitatively evaluating patients with primary progressive aphasia. Commonly adopted approaches are time-consuming, of limited accuracy or designed to assess different patient populations. This paper introduces a new clinical test-the Mini Linguistic State Examination-which was designed uniquely to enable a clinician to assess and subclassify both classical and mixed presentations of primary progressive aphasia. The adoption of a novel assessment method (error classification) greatly amplifies the clinical information that can be derived from a set of standard linguistic tasks and allows a five-dimensional profile to be defined. Fifty-four patients and 30 matched controls were recruited. Five domains of language competence (motor speech, phonology, semantics, syntax and working memory) were assessed using a sequence of 11 distinct linguistic assays. A random forest classification was used to assess the diagnostic accuracy for predicting primary progressive aphasia subtypes and create a decision tree as a guide to clinical classification. The random forest prediction model was 96% accurate overall (92% for the logopenic variant, 93% for the semantic variant and 98% for the non-fluent variant). The derived decision tree produced a correct classification of 91% of participants whose data were not included in the training set. The Mini Linguistic State Examination is a new cognitive test incorporating a novel and powerful, yet straightforward, approach to scoring. Rigorous assessment of its diagnostic accuracy confirmed excellent matching of primary progressive aphasia syndromes to clinical gold standard diagnoses. Adoption of the Mini Linguistic State Examination by clinicians will have a decisive impact on the consistency and uniformity with which patients can be described clinically. It will also facilitate screening for cohort-based research, including future therapeutic trials, and is suitable for describing, quantifying and monitoring language deficits in other brain disorders.
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Maple syrup urine disease (MSUD, MIM #248600) is an autosomal recessive metabolic disorder that results in elevation of the branched-chain amino acids (BCAA) leucine, isoleucine, and valine. Elevation of BCAA and certain alpha keto-acids is associated with a catabolic state and may result in neurological and developmental delays, feeding problems, and a urine and cerumen odor of maple syrup. Pregnancy is a period of multiple adaptations necessary to support fetal growth and development. Both the third trimester of pregnancy and the postpartum period present the possibility for catabolic states. We describe our treatment of an adolescent patient with intermittent MSUD and her resulting positive pregnancy outcome.
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Two deep ice cores from central Greenland, drilled in the 1990s, have played a key role in climate reconstructions of the Northern Hemisphere, but the oldest sections of the cores were disturbed in chronology owing to ice folding near the bedrock. Here we present an undisturbed climate record from a North Greenland ice core, which extends back to 123,000 years before the present, within the last interglacial period. The oxygen isotopes in the ice imply that climate was stable during the last interglacial period, with temperatures 5 degrees C warmer than today. We find unexpectedly large temperature differences between our new record from northern Greenland and the undisturbed sections of the cores from central Greenland, suggesting that the extent of ice in the Northern Hemisphere modulated the latitudinal temperature gradients in Greenland. This record shows a slow decline in temperatures that marked the initiation of the last glacial period. Our record reveals a hitherto unrecognized warm period initiated by an abrupt climate warming about 115,000 years ago, before glacial conditions were fully developed. This event does not appear to have an immediate Antarctic counterpart, suggesting that the climate see-saw between the hemispheres (which dominated the last glacial period) was not operating at this time.
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In vitro skin absorption methods exist in Organisation for Economic Co-operation and Development (OECD) guideline form (No. 428) and are used to estimate the degree of systemic penetration of chemicals through skin. More detailed kinetics of permeation through skin compartments are not described well by existing methods. This study was designed to assess the practical feasibility of generating compartmental (stratum corneum/epidermal/dermal) disposition and kinetic data of topically applied chemicals. For chemically induced effects initiated in the skin (e.g., skin allergy), the delivery of tissue concentrations of chemical will impact the incidence and severity of biological effect. Explicit data on the kinetics of chemical disposition in skin have not traditionally been needed for skin allergy risk assessment: current in vivo assays embody delivery implicitly. Under the 7th Amendment to the European Cosmetics Directive, in vivo assays (such as the local lymph node assay for skin sensitization) will not be permitted to assess cosmetic ingredients. New in vitro and in silico alternative approaches and ways of predicting risk of adverse effects in humans need to be developed, and new methods such as that described here provide a way of estimating delivered concentrations and the effect of formulation changes on that delivery. As we continue to deconstruct the contributing factors of skin allergy in humans, it will be useful to have methods available that can measure skin tissue compartment exposure levels delivered from different exposure use scenarios. Here we provide such a method. The method could also be used to generate useful data for developing in silico kinetic models of compartmental skin delivery and for refining data for skin delivery in relation to the evaluation of systemic toxicity.
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Acroleína/análogos & derivados , Alérgenos/metabolismo , Absorção Cutânea/fisiologia , Acetona , Acroleína/metabolismo , Adulto , Etanol , Feminino , Humanos , Pessoa de Meia-Idade , Azeite de Oliva , Óleos de Plantas , Propilenoglicol , Pele/metabolismo , Técnicas de Cultura de TecidosRESUMO
In this review, we discuss and compare studies of xenobiotic metabolism in both human skin and 3D human skin reconstructs. In comparison to the liver, the skin is a less studied organ in terms of characterising metabolic capability. While the skin forms the major protective barrier to environmental chemical exposure, it is also a potential target organ for adverse health effects. Occupational, accidental or intended-use exposure to toxic chemicals could result in acute or delayed injury to the skin (e.g. inflammation, allergy, cancer). Skin metabolism may play a role in the manifestation or amelioration of adverse effects via the topical route. Today, we have robust testing strategies to assess the potential for local skin toxicity of chemical exposure. Such methods (e.g. the local lymph node assay for assessing skin sensitisation; skin painting carcinogenicity studies) incorporate skin metabolism implicitly in the in vivo model system used. In light of recent European legislation (i.e. 7(th) Amendment to the Cosmetics Directive and Registration Evaluation and Authorisation of existing Chemicals (REACH)), non-animal approaches will be required to reduce and replace animal experiments for chemical risk assessment. It is expected that new models and approaches will need to account for skin metabolism explicitly, as the mechanisms of adverse effects in the skin are deconvoluted. 3D skin models have been proposed as a tool to use in new in vitro alternative approaches. In order to be able to use 3D skin models in this context, we need to understand their metabolic competency in relation to xenobiotic biotransformation and whether functional activity is representative of that seen in human skin.
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Modelos Biológicos , Pele/metabolismo , Xenobióticos/metabolismo , Biotransformação , Humanos , Pele/enzimologiaRESUMO
OBJECTIVES: Little is known about the influence of control beliefs on antiretroviral drug adherence in patients who migrated from sub-Saharan Africa to Europe. The aim of this study was to explore the differences in health locus of control and control beliefs between HIV infected patients from sub-Saharan Africa with and without a lifetime experience of migration. METHODS: A sample of 62 HIV infected consecutive patients referred to the HIV clinics at the University Hospital of Münster (Germany) and at the Rubaga Hospital Kampala (Uganda) were enrolled into this study. We compared three groups of patients: sub-Saharan African migrants, German patients, and local Ugandan patients. We used the German health and illness related control beliefs questionnaire (KKG), the Competence and control beliefs questionnaire (FKK), and the Powe Fatalism Inventory-HIV/AIDS-Version (PFI-HIV/AIDS-Version) and translated these scales into English and Luganda. In addition, the patients' sociodemographic, acculturation, clinical, and immunological data were registered. RESULTS: Significant results were shown in HIV related external locus of control between migrated sub-Saharan African and local Ugandan patients compared to German patients. General control beliefs showed no significant differences. In the PFI-HIV-Version, there was a significant difference between migrated sub-Saharan African and Ugandan patients compared to German patients. CONCLUSIONS: Our data suggest that the experience of migration does not influence the locus of control. Compared to German HIV patients, African patients in general showed a significantly higher external health locus of control which might have implications for drug adherence.
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Fármacos Anti-HIV/administração & dosagem , Atitude Frente a Saúde , Infecções por HIV/tratamento farmacológico , Infecções por HIV/psicologia , Controle Interno-Externo , Adesão à Medicação/psicologia , Migrantes/psicologia , Adulto , África Subsaariana/etnologia , Feminino , Alemanha/epidemiologia , Humanos , Masculino , Adesão à Medicação/estatística & dados numéricos , Pessoa de Meia-Idade , Inquéritos e Questionários , Traduções , Uganda/epidemiologiaRESUMO
Examination of a 14-year-old male who was admitted to an inpatient unit with an acute paranoid syndrome yielded serious organic findings: macroencephaly, head tilted to one side, strabismus, neurological deficits, hydroencephaly and an expressive speech disorder. The personal and family history revealed a disturbance of motor development since infancy and psychiatric illness in the immediate family. The medication and the surgical procedure selected--endoscopic third ventriculostomy--are described and the difficult differential diagnosis is discussed.
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Aqueduto do Mesencéfalo , Hidrocefalia/diagnóstico , Transtornos Neurocognitivos/diagnóstico , Transtornos Paranoides/diagnóstico , Adolescente , Aqueduto do Mesencéfalo/cirurgia , Diagnóstico Diferencial , Humanos , Hidrocefalia/psicologia , Hidrocefalia/cirurgia , Masculino , Transtornos Neurocognitivos/psicologia , Transtornos Neurocognitivos/cirurgia , Transtornos Paranoides/psicologia , Transtornos Paranoides/cirurgia , VentriculostomiaRESUMO
One possible side effect of selective serotonin re-uptake inhibitors (SSRI) is the exacerbation of nervous tics in a 12-year-old boy treated with tiapride following prescription of paroxetine for a depressive syndrome. Potential causal factors include residual cholinergic activity of paroxetine, the observably increased drive under paroxetine, metabolic properties, and protein binding. The problem of side effects under selective serotonin re-uptake inhibitors, as well as the issues of co-morbidity and co-medication in the treatment of nervous tics and Tourette's Syndrome are discussed.
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Antidepressivos Tricíclicos/uso terapêutico , Depressão/etiologia , Paroxetina/efeitos adversos , Inibidores Seletivos de Recaptação de Serotonina/efeitos adversos , Tiques/induzido quimicamente , Síndrome de Tourette/complicações , Síndrome de Tourette/tratamento farmacológico , Antidepressivos Tricíclicos/administração & dosagem , Criança , Relação Dose-Resposta a Droga , Quimioterapia Combinada , Fluvoxamina/administração & dosagem , Fluvoxamina/efeitos adversos , Humanos , Masculino , Paroxetina/administração & dosagem , Inibidores Seletivos de Recaptação de Serotonina/administração & dosagem , Tiques/etiologia , Resultado do Tratamento , Trimipramina/uso terapêuticoRESUMO
The restriction of parental rights includes not only legal but also therapeutic aspects. The therapeutic aspects refer first to the child's disorder and then to its resulting needs. Furthermore a restriction of parental rights could be necessary for therapeutic reasons when the parents' reaction to reality is insufficient, usually caused by parental psychiatric disorders. The expert's counsel should facilitate the communication with disturbed parents thus engendering an improved reality-insight by the parents. Successful helping strategies can thus be made workable. The expert, the judge and the local authority social services should mutually respect specifically defined role-functions. The communication barriers between parents and helpers can only this way be partially resolved. The expert's evidence requires a high professional competence and responsibility and goes over and above the professional contribution from family therapy.
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Custódia da Criança/legislação & jurisprudência , Proteção da Criança/legislação & jurisprudência , Prova Pericial/legislação & jurisprudência , Psicoterapia/legislação & jurisprudência , Adolescente , Criança , Filho de Pais com Deficiência/legislação & jurisprudência , Pré-Escolar , Divórcio/legislação & jurisprudência , Feminino , Alemanha , Humanos , Lactente , Masculino , Transtornos Mentais/diagnóstico , Transtornos Mentais/terapia , Relações Profissional-FamíliaRESUMO
Within the clinical practice of child and adolescent psychiatry, the needs of the child are recurrently endangered by parents' expectations and/or behaviour. The task of the doctors, therapists and local authority social workers is to work together with the child's parents or guardians in order to assess their parental competence and if need be to contravene the latter with a care order. According to German law there are different possibilities of restricting the patients' rights or making a care order for children and adolescents up to the age of 18 years. The local authority social services department may make a care order especially according to the wishes of the child or the adolescent or when other circumstances necessitate it, and obtain parental consent afterwards (section 42 KJHG). The rights of the parents may be restricted in either single areas eg the place of the child's residence (section 1666 BGB) or completely (section 1666a BGB) in cooperation with the guardianship judge. The task of the judge is to decide within the legal context whether such a restriction of parental responsibility is necessary to protect the child.
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Psiquiatria do Adolescente/legislação & jurisprudência , Custódia da Criança/legislação & jurisprudência , Psiquiatria Infantil/legislação & jurisprudência , Proteção da Criança/legislação & jurisprudência , Adolescente , Criança , Alemanha , Humanos , Equipe de Assistência ao Paciente/legislação & jurisprudênciaRESUMO
Development of risk assessment methods for skin sensitization in the absence of toxicological data generated in animals represents a major scientific and technical challenge. The first step in human skin sensitization induction is the transport of sensitizer from the applied dose on the skin surface to the epidermis, where innate immune activation occurs. Building on the previous development of a time course in vitro human skin permeation assay, new kinetic data for 10 sensitizers and 2 nonsensitizers are reported. Multicompartmental modeling has been applied to analyze the data and determine candidate dose parameters for use in integrated risk assessment methods: the area under the curve (AUC) and maximum concentration (C(max)) in the epidermis. A model with two skin compartments, representing the stratum corneum and viable skin (epidermis and dermis), was chosen following a formal model selection process. Estimates of the uncertainty, as well as average values of the epidermal disposition kinetics parameters, were made by fitting to the time course skin permeation data from individual skin donors. A potential reduced time course method is proposed based on two time points at 4 and 24 h, which gives results close to those from the full time course for the current data sets. The time course data presented in this work have been provided as a resource for development of predictive in silico skin permeation models.
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Farmacocinética , Pele/efeitos dos fármacos , Área Sob a Curva , Humanos , Técnicas In Vitro , Modelos Teóricos , Medição de Risco , Pele/metabolismoRESUMO
Inductively coupled plasma mass spectrometry (ICP-MS) is a suitable tool for multi-element analysis at low concentration levels. Rare earth element (REE) determinations in standard reference materials and small volumes of molten ice core samples from Antarctica have been performed with an ICP-time of flight-MS (ICP-TOF-MS) system. Recovery rates for REE in e.g. SPS-SW1 amounted to approximately 103%, and the relative standard deviations were 3.4% for replicate analysis at REE concentrations in the lower ngL(-1) range. Analyses of REE concentrations in Antarctic ice core samples showed that the ICP-TOF-MS technique meets the demands of restricted sample mass. The data obtained are in good agreement with ICP-Quadrupole-MS (ICP-Q-MS) and ICP-Sector Field-MS (ICP-SF-MS) results. The ICP-TOF-MS system determines accurately and precisely REE concentrations exceeding 5ngL(-1) while between 0.5 and 5ngL(-1) accuracy and precision are element dependent.
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Gelo/análise , Espectrometria de Massas/instrumentação , Espectrometria de Massas/métodos , Metais Terras Raras/análise , Regiões Antárticas , Fatores de TempoRESUMO
Psychiatric Assessment of juvenile offenders deals with criteria of maturity on the one hand as well as psychiatric disorders as factors of lessened responsibility on the other. Rivalry of both in German criminal legislation for youths between 14 and 18 is discussed, especially as regards aspects of practical proceedings.