RESUMO
Previous studies have observed a sex-dependent lateralization of amygdala activation related to emotional memory. Specifically, it was shown that the activity of the right amygdala correlates significantly stronger with memory for images judged as arousing in men than in women, and that there is a significantly stronger relationship in women than in men between activity of the left amygdala and memory for arousing images. Using a large sample of 235 male adolescents and 235 females matched for age and handedness, we investigated the sex-specific lateralization of amygdala activation during an emotional face perception fMRI task. Performing a formal sex by hemisphere analysis, we observed in males a significantly stronger right amygdala activation as compared to females. Our results indicate that adolescents display a sex-dependent lateralization of amygdala activation that is also present in basic processes of emotional perception. This finding suggests a sex-dependent development of human emotion processing and may further implicate possible etiological pathways for mental disorders most frequent in adolescent males (i.e., conduct disorder).
Assuntos
Tonsila do Cerebelo/fisiologia , Lateralidade Funcional/fisiologia , Reconhecimento Psicológico/fisiologia , Adolescente , Ira/fisiologia , Expressão Facial , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Desempenho Psicomotor/fisiologia , Caracteres SexuaisRESUMO
A fundamental function of the brain is to evaluate the emotional and motivational significance of stimuli and to adapt behaviour accordingly. The IMAGEN study is the first multicentre genetic-neuroimaging study aimed at identifying the genetic and neurobiological basis of individual variability in impulsivity, reinforcer sensitivity and emotional reactivity, and determining their predictive value for the development of frequent psychiatric disorders. Comprehensive behavioural and neuropsychological characterization, functional and structural neuroimaging and genome-wide association analyses of 2000 14-year-old adolescents are combined with functional genetics in animal and human models. Results will be validated in 1000 adolescents from the Canadian Saguenay Youth Study. The sample will be followed up longitudinally at the age of 16 years to investigate the predictive value of genetics and intermediate phenotypes for the development of frequent psychiatric disorders. This review describes the strategies the IMAGEN consortium used to meet the challenges posed by large-scale multicentre imaging-genomics investigations. We provide detailed methods and Standard Operating Procedures that we hope will be helpful for the design of future studies. These include standardization of the clinical, psychometric and neuroimaging-acquisition protocols, development of a central database for efficient analyses of large multimodal data sets and new analytic approaches to large-scale genetic neuroimaging analyses.
Assuntos
Pesquisa Comportamental/normas , Emoções/fisiologia , Estudo de Associação Genômica Ampla/normas , Comportamento Impulsivo/fisiopatologia , Transtornos Mentais/fisiopatologia , Adolescente , Animais , Pesquisa Comportamental/métodos , Encéfalo/fisiologia , Encéfalo/fisiopatologia , Mapeamento Encefálico/métodos , Mapeamento Encefálico/normas , Modelos Animais de Doenças , Estudo de Associação Genômica Ampla/métodos , Humanos , Comportamento Impulsivo/genética , Individualidade , Transtornos Mentais/genética , Seleção de Pacientes , Prazer/fisiologia , RecompensaRESUMO
The management of residues from thermal waste treatment is an integral part of waste management systems. The primary goal of managing incineration residues is to prevent any impact on our health or environment caused by unacceptable particulate, gaseous and/or solute emissions. This paper provides insight into the most important measures for putting this requirement into practice. It also offers an overview of the factors and processes affecting these mitigating measures as well as the short- and long-term behavior of residues from thermal waste treatment under different scenarios. General conditions affecting the emission rate of salts and metals are shown as well as factors relevant to mitigating measures or sources of gaseous emissions.
Assuntos
Poluição do Ar/prevenção & controle , Eliminação de Resíduos , Arquitetura de Instituições de Saúde , Gases , IncineraçãoRESUMO
In a preliminary report a new functional chromosome model is developed. Contrary to all present hypotheses this model considers not only the chromomeres but also the interchromomeres as independent genes. It is assumed that the interchromomeres are obligatory miniature-puffs, which are formed by the genes of "basic synthesis" (the synthesis which guarantees the fundamental cellular life). The genes involved in the basic synthesis are collectively defined as the "basic genome". The chromomeres developed during evolution through saltatory replication from the basic genes and contain the loci of the stage- and tissue-specific differential gene activity. All the genes of the differential synthesis are designated as the "differential genome".ZUSAMMENFASSUNG: In einer vorläufigen Mitteilung wird ein neues funktionelles Chromosomenmodell entwickelt, das entgegen allen bisherigen Hypothesen sowohl Chromomeren als auch Interchromomeren als eigenständige Gene betrachtet. Es wird angenommen, daß die Interchromomeren obligatorische Miniatur-Puffs sind, die von den Genen der jeder Zelle gleichermaßen eigenen "Basissynthese" gebildet werden. Die Summe der Gene, die an der Basissynthese beteiligt sind, wird als "Basisgenom" definiert. Die Chromomeren haben sich während der Evolution durch saltatorische Replikation aus Basisgenen entwickelt und enthalten die Loci der Stadien- und gewebespezifischen differentiellen Genaktivität. Ihre Gesamtheit wird als "Differentialgenom" definiert.Für die Anregung zu dieser Arbeit gilt Herrn Prof. Dr. F. Mechelke mein besonderer Dank.
RESUMO
Scanning electron microscopy (SEM) with energy-dispersive X-ray microanalysis (EDX) is frequently used for morphological and qualitative chemical characterization of different materials. The applicability of this method for phase identification, is, however, often underestimated. The application of SEM/EDX for the characterization of different phases in fresh and altered municipal-waste incinerator bottom-ash samples with high lateral resolution is presented. Polished thin sections were prepared from the samples, but fresh fracture surfaces were also used. The EDX analyses were performed by using the correction procedures of a conventional standardless ZAF correction, a peak-to-background ZAF correction, and a correction method for light-element analysis. Because of their highly reactive properties the bottom-ash SEM samples require a special method of preparation. The method facilitates nondestructive preparation of the sensitive bottom-ash alteration phases (e.g. cement phases, hydroxides, salts) and their microstructures.
RESUMO
Persistent infection by Sindbis virus (SV) can be induced in cultures of BHK-21 cells. In a persistently infected cell line only 5% of the cells produced virus. Virus titers in the medium reached 10(5) PFU per ml. A persistent infection could be eliminated from cultures by seeding at most 100 cells per bottle. Compared with the original line decontaminated lines differed in several properties. After infection with SV ten times less virus was released into the medium, and an infection persisted without producing periodic cell destructions as observed in establishing a persistent infection in the original line. In decontaminated lines plaques formed by different viruses were either not visible or smaller than those in normal cells. Persistently infected as well as decontaminated lines had lost three chromosomes. The altered cell type of persistently infected lines apparently originated by selection of a cell mutant which was not destroyed by SV. Results suggested that a small number of cells susceptible to the virus continuously arises from the population of altered cells, and that virus infection is transmitted and maintained in the cultures by these sensitive cells.
Assuntos
Sindbis virus/patogenicidade , Animais , Divisão Celular , Linhagem Celular , Sobrevivência Celular , Cromossomos/análise , Cricetinae , Rim , Mutação , Ensaio de Placa Viral , Replicação ViralRESUMO
Epstein-Barr virus (EBV), the causative agent of mononucleosis and several human cancers, infects cells via complement receptor type 2 (CR2, CD21) which also serves as the receptor for the third complement component, C3. Expression of this receptor is restricted to B lymphocytes, immature thymocytes, and certain epithelial cells. In the present investigation; we describe the presence of a seemingly novel EBV receptor which is phenotypically distinct from CR2. Among various leukemic T cells studied, one, HSB-2, demonstrates no reactivity to several anti-CR2 antibodies, yet it reacts strongly with EBV as detected by incubation with biotin-conjugated virus and streptavidin-phycoerythrin. The virus binding is specific as demonstrated by blocking with anti-EBV antibodies and with non-conjugated virus. Aggregated C3 also binds HSB-2 and is capable of partially inhibiting EBV binding. The absence of CR2 on HSB-2 is further supported by the lack of expression of specific mRNA, assessed by Northern blotting analysis and polymerase chain reaction. Viral internalization and infection is demonstrated with electron microscopy, with detection of EBV-DNA by Southern blotting, and with detection of EBNA-1 transcripts by the polymerase chain reaction. Even though HSB-2 does not express CR2, it nevertheless displays transcripts which have some homology to a CR2 cDNA probe under low stringency hybridization conditions. This probe encompasses approximately the N-terminal half of CR2 which includes the EBV-binding epitope(s). The HSB-2 message is 5.2 kb, a size distinct from the 4.7-kb message of B cell CR2s. In contrast, the 5.2-kb message in not seen, under similar hybridization conditions, with a probe comprising the C-terminal half of CR2. Collectively, the data indicate that a receptor molecule having distinct phenotypic characteristics from the known CR2 protein on B cells is utilized by EBV to target human T lymphocytes.
Assuntos
Receptores de Complemento/análise , Linfócitos T/microbiologia , Animais , Antígenos de Diferenciação de Linfócitos B/análise , Antígenos de Diferenciação de Linfócitos B/genética , Sequência de Bases , Linhagem Celular , Genes Virais , Herpesvirus Humano 4/genética , Herpesvirus Humano 4/metabolismo , Dados de Sequência Molecular , Fenótipo , Receptores de Complemento/genética , Receptores de Complemento 3d , Transcrição GênicaRESUMO
EBV is a human herpes virus that causes mononucleosis and is associated with various tumors. EBV infects cells via the CR2 that was previously thought to be expressed only on the surface of B cells and certain epithelial cells. Recent findings in our laboratory and those of others, however, have shown that the EBV receptor is also present on T cells. Our study shows that Jurkat human T cells have a molecule that reacts with both anti-CR2 antibodies and the third component of complement, C3. Furthermore, the data indicate that this molecule binds EBV detected by incubation with biotin-conjugated virus and streptavidin phycoerythrin. Viral binding is specific, as it is inhibited by nonconjugated virus, with anti-CR2 antibodies, and with an antibody reactive with the glycoprotein (gp350) that EBV uses to bind CR2. In addition, EBV variably infects Jurkat cells as demonstrated by the presence of transcripts of Epstein Barr nuclear Ag (EBNA-1) using the polymerase chain reaction. Immunoprecipitation experiments with anti-CR2 antibodies and SDS-PAGE analysis reveal a protein with an apparent molecular mass of 155 kDa which is higher than the one seen in B cells. The size of this molecule is reduced to 119 kDa upon endoglycosidase F treatment. Northern blot analysis of Jurkat poly(A)+ RNA shows a transcript of 4.7 kb upon probing with the B cell CR2 cDNA. This size is consistent with that of B cell CR2 mRNA. Two cDNA clones were identified upon screening of a Jurkat cell cDNA library with the B cell CR2 cDNA. One of the clones possesses an identical nucleotide sequence to the one corresponding to B cell CR2, whereas the other represents a differentially spliced transcript which lacks the exon 8b of B cell CR2. Analysis of Jurkat and Raji mRNA by PCR demonstrated the presence of this novel splice variant in both cell lines.