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1.
J Geophys Res Solid Earth ; 126(9): e2021JB022200, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35845177

RESUMO

The 2016-2017 Central Italy earthquake sequence struck the central Apennines between August 2016 and October 2016 with Mw ∈ [5.9; 6.5], plus four earthquakes occurring in January 2017 with Mw ∈ [5.0; 5.5]. We study Global Positioning System time series including near- and far-field domains. We use a variational Bayesian independent component analysis technique to separate the post-seismic deformation from signals caused by variation of the water content in aquifers at hundreds of meters of depth and of the soil moisture. For each independent component, realistic uncertainties and a plausible physical explanation are provided. We focus on the study of afterslip on the main structures surrounding the mainshock, highlighting the role played by faults that were not activated during the co-seismic phase in accommodating the post-seismic deformation. We report aseismic deformation occurring on the Paganica fault, which hosted the Mw 6.1 2009 L'Aquila earthquake, suggesting that static stress transfer and aseismic slip influence the recurrence time of nearby (∼50 km further south of the mainshocks) segments. A ∼2-3 km thick subhorizontal shear-zone, clearly illuminated by seismicity, which bounds at depth the west-dipping normal faults where the mainshocks nucleated, also shows aseismic slip. Since afterslip alone underestimates the displacement in the far-field domain, we consider the possibility that the shear zone marks the brittle-ductile transition, assuming the viscoelastic relaxation of the lower crust as a mechanism contributing to the post-seismic displacement. Our results suggest that multiple deformation processes are active in the first 2 years after the mainshocks.

2.
Cogn Process ; 16 Suppl 1: 233-6, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26233529

RESUMO

BACKGROUND: The thesis of embodied cognition claims that perception of the environment entails a complex set of multisensory processes which forms a basis for the agent's potential and immediate actions. However, in the case of artworks, an agent becomes an observer and action turns into a reaction. This raises questions about the presence of embodied or situated cognition involved in art reception. AIMS: The study aimed to assess the bodily correlates of perceiving fictional pictorial spaces in the absence of a possibility of an actual physical immersion or manipulation of represented forms. METHOD: The subjects were presented with paintings by Vermeer and De Hooch, whilst their body sway and eye movements were recorded. Moreover, test and questionnaires on mental imagery (MRT, VVIQ and OSIQ) were administered. RESULTS: Three major results were obtained: (1) the degree of pictorial depth did not influence body sway; (2) fixations to distant elements in paintings (i.e. backgrounds) were accompanied by an increase in body sway; and (3) mental rotation test scores correlated positively with body sway. CONCLUSIONS: Our results suggest that in certain cases--despite the fictional character of art--observers' reactions resemble reactions to real stimuli. It is proposed that these reactions are mediated by mental imagery (e.g. mental rotation) that contributes to the act of representing alternative to real artistic spaces.


Assuntos
Percepção de Profundidade/fisiologia , Imaginação , Pinturas , Postura , Percepção Espacial/fisiologia , Adulto , Movimentos Oculares , Feminino , Humanos , Masculino , Equilíbrio Postural/fisiologia , Adulto Jovem
3.
Med Vet Entomol ; 29(4): 361-70, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26177673

RESUMO

The secretory region of the salivary glands in Glossina pallidipes Austen (Diptera: Glossinidae) is characterized by an external muscle layer. Scanning electron microscopy and transmission electron microscopy investigations provide a detailed description of the longitudinal muscle fibres and a comparison of their structure when affected by salivary gland hypertrophy virus. The virus is responsible for hypertrophy of the salivary glands in symptomatic flies, specifically of the muscle fibres, the cytoarchitecture of which is completely altered. Although observations did not reveal viral particles in the muscle cells of either asymptomatic or symptomatic flies, muscle fibres were enlarged and detached from one another and their associated basement membrane only in symptomatic flies. A decrease in type IV collagen labelling in the basement membrane of the muscles in symptomatic flies is reported and is considered a potential cause of the salivary gland muscle alteration and, possibly, myopathy. The maintenance of an organized muscular layer is essential for the normal secretion of saliva and hence its pathology in symptomatic tsetse flies could affect the normal transmission of the trypanosome that develops inside the salivary gland epithelium. Therefore, a better understanding of the possible role of the virus is essential in order to elucidate its impact on salivary deployment in symptomatic flies.


Assuntos
Vírus de DNA/fisiologia , Moscas Tsé-Tsé/crescimento & desenvolvimento , Moscas Tsé-Tsé/virologia , Animais , Feminino , Masculino , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Microscopia de Fluorescência , Glândulas Salivares/anatomia & histologia , Glândulas Salivares/crescimento & desenvolvimento , Glândulas Salivares/ultraestrutura , Glândulas Salivares/virologia , Moscas Tsé-Tsé/anatomia & histologia , Moscas Tsé-Tsé/ultraestrutura
4.
Fish Shellfish Immunol ; 42(2): 483-93, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25475077

RESUMO

MHC II-ß chain gene transcripts were quantified by real-time PCR and localised by in situ hybridization in the developing thymus of the teleost Dicentrarchus labrax, regarding the specialization of the thymic compartments. MHC II-ß expression significantly rose when the first lymphoid colonization of the thymus occurred, thereafter increased further when the organ progressively developed cortex and medulla regions. The evolving patterns of MHC II-ß expression provided anatomical insights into some mechanisms of thymocyte selection. Among the stromal cells transcribing MHC II-ß, scattered cortical epithelial cells appeared likely involved in the positive selection, while those abundant in the cortico-medullary border and medulla in the negative selection. These latter most represent dendritic cells, based on typical localization and phenotype. These findings provide further proofs that efficient mechanisms leading to maturation of naïve T cells are operative in teleosts, strongly reminiscent of the models conserved in more evolved gnathostomes.


Assuntos
Bass/genética , Bass/imunologia , Genes MHC da Classe II , Ativação Linfocitária , Timo/metabolismo , Animais , Bass/metabolismo , Hibridização In Situ/veterinária , Reação em Cadeia da Polimerase em Tempo Real/veterinária , Timócitos/citologia , Timócitos/metabolismo , Timo/crescimento & desenvolvimento
5.
Fish Shellfish Immunol ; 34(5): 1335-44, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23470814

RESUMO

The pharmacological potential of Aloe arborescens Miller leaf components was investigated, with special attention deserved to immune modulatory effects on the Sparus aurata fibroblast cell line SAF-1. The cells were treated with Aloe extract at different concentrations (1.2-4.8 mg ml(-1)) for various times (24-72 h). The lowest concentration did not provoke any cellular damage observable by SEM and did not affect ATP amounts after 24 and 48 h, while even induced a significant increase over controls after 72 h. We next examined the transcription kinetics of different immune-related genes (IL-1ß, TGF-ß, TNF-α, COX-2, IFN-I, Mx and MHCI-α) in SAF-1 cells stimulated with LPS or poly I:C. The Aloe extract (1.2 mg ml(-1)) acted as a powerful immune stimulant in LPS- or poly I:C-activated SAF-1 cells, inducing a synergic effect on interconnected genes that are expected to be involved in different aspects of the immune responses. These reports provide a new perspective for the use of A. arborescens to prevent or oppose bacterial and viral fish diseases and to face, as an alternative strategy based on natural plant extracts, the growing unwillingness to rely upon standard solutions involving antibiotics or antimicrobial chemicals.


Assuntos
Aloe/química , Regulação da Expressão Gênica , Extratos Vegetais/farmacologia , Dourada/genética , Dourada/imunologia , Animais , Linhagem Celular , Lipopolissacarídeos/farmacologia , Folhas de Planta/química , Poli I-C/farmacologia
6.
Fish Shellfish Immunol ; 30(2): 609-17, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21168509

RESUMO

Cellular and molecular data have evidenced a gut-associated lymphoid tissue in a variety of teleost species, abundantly containing T cells, whose origin, selection and functions are still unclear. This study reports CD4, CD8-α, MHCI-α, MHCII-ß, rag-1 and TCR-ß gene transcription along the intestine (anterior, middle and posterior segments) and in the thymus of one year-old Dicentrarchus labrax (L.). Real-time PCR findings depicted a main role of the thymus in T-cell development, but also rag-1 and CD8-α transcripts are detected in the intestine, having significant expression in the posterior segment. In the whole intestine TCR-ß and CD8-α exceeded CD4 transcripts. RNA ISH confirmed these data and detailed that mucosal CD8-α+ cells were especially numerous in the epithelium and in aggregates in the lamina propria. Regional differences in T-cell-specific gene expressions are first described in the intestine of a bony fish. High non-specific cytotoxic activity against xenogeneic and allogeneic cells was found in lymphocytes purified from the intestinal mucosa, providing further insight into their local defence roles.


Assuntos
Bass/imunologia , Regulação da Expressão Gênica/imunologia , Intestinos/imunologia , Linfócitos T/imunologia , Animais , Antígenos CD4/genética , Testes Imunológicos de Citotoxicidade , Perfilação da Expressão Gênica , Genes MHC da Classe II/genética , Genes Codificadores da Cadeia beta de Receptores de Linfócitos T/genética , Reação em Cadeia da Polimerase , Timo/imunologia
7.
Ann Trop Med Parasitol ; 104(3): 237-46, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20507697

RESUMO

Leptoconops spp. are small midges, members of the family Ceratopogonidae, that are relatively widespread in wetlands with sandy or silty-clay soils, including many tourist sites. Although very few of the species are proven vectors of pathogens, the blood-feeding females attack mammals, including humans, in large swarms and their painful bites may cause severe reactions, especially in children. Although Leptoconops spp. may limit the socio-economic development of an area, there are currently no effective methods for the control of their natural populations, and the repellents and netting used against mosquitoes are ineffective against these midges. The diurnal control of the adults with pesticides may have unacceptable impacts on non-target species, including humans, and be ineffective because the adult females can easily be carried, from untreated areas to treated, on the wind. In the present study, the use of a diflubenzuron-based insecticide against the larvae of Leptoconops (Holoconops) kerteszi Kieffer, 1908 - a sand-reproducing species that is widespread in certain coastal areas of the Italian province of Grosseto - was explored. In Grosseto, in summer, attacks by swarms of adult L. kerteszi create problems for the local people and the many tourists. The encouraging results of preliminary tests are discussed in relation to the potential use of diflubenzuron for the integrated control of L. kerteszi populations.


Assuntos
Ceratopogonidae , Diflubenzuron , Mordeduras e Picadas de Insetos/prevenção & controle , Controle de Insetos/métodos , Inseticidas , Animais , Ceratopogonidae/crescimento & desenvolvimento , Criança , Reservatórios de Doenças , Feminino , Humanos , Itália , Larva , Áreas Alagadas
8.
Acta Psychol (Amst) ; 132(2): 190-200, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19695558

RESUMO

In the present fMRI study the issue of the specific cortices activation during imagery generation in different sensory modalities is addressed. In particular, we tested whether the vividness variability of imagery was reflected in the BOLD signal within specific sensory cortices. Subjects were asked to generate a mental image for each auditory presented sentence. Each imagery modality was contrasted with an abstract sentence condition. In addition, subjects were asked to fill the Italian version of the Questionnaire Upon Mental Imagery (QMI) prior to each neuroimaging session. In general, greater involvement of sensory specific cortices in high-vivid versus low-vivid subjects was found for visual (occipital), gustatory (anterior insula), kinaesthetic (pre-motor), and tactile and for somatic (post-central parietal) imagery modalities. These results support the hypothesis that vividness is related to image format: high-vivid subjects would create more analogical representations relying on the same specific neural substrates active during perception with respect to low-vivid subjects. Results are also discussed according to the simulation perspective.


Assuntos
Mapeamento Encefálico , Córtex Cerebral/fisiologia , Imaginação/fisiologia , Sensação/fisiologia , Adulto , Feminino , Humanos , Modelos Lineares , Imageamento por Ressonância Magnética , Cidade de Roma
9.
Insect Mol Biol ; 18(2): 203-11, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19320761

RESUMO

Contrary to what was assumed regarding the presence of respiratory proteins in insects, a functional hemocyanin was recently found in larvae and adults of the stoneflies species Perla marginata, whereas in the close species Perla grandis, hemocyanin functionality was deduced from sequence data. In order to verify if the presence of this ancient trait is widespread within the order and to investigate why stoneflies have maintained it, we have extended the search for hemocyanin to species of other Plecoptera families. In particular, we assessed the presence of hemocyanin in the larval stage of nine Plecoptera species, belonging to six of the seven families of the European stonefly-fauna, and analyzed its potential functionality as deduced by sequence data. We cloned and sequenced the corresponding cDNAs and studied their expression with RT-PCR technique. Moreover, we performed homology studies using the deduced amino acid sequences. On the basis of our analysis, we hypothesized a functional role of the hemocyanin only for two species: Dinocras cephalotes and Isoperla grammatica (Perloidea). In all the investigated Nemouroidea and in Siphonoperla torrentium (Perloidea), this protein may have been lost. Larval size, life-cycle length, trophic role and environmental induction are discussed as possible explanations of these different physiological requirements.


Assuntos
Hemocianinas/metabolismo , Proteínas de Insetos/metabolismo , Insetos/crescimento & desenvolvimento , Insetos/metabolismo , Animais , Hemocianinas/química , Proteínas de Insetos/química , Larva , Ninfa , Filogenia , Alinhamento de Sequência , Análise de Sequência de DNA , Homologia de Sequência de Aminoácidos
10.
Cell Tissue Res ; 336(1): 31-40, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19214582

RESUMO

The thyroid-stimulating hormone (TSH) receptor (TSHr) was made specifically fluorescent by insertion of a tetracysteine motif (TSHr-FlAsH) into the C-terminal end and transiently transfected into COS-7 and HeLa cells. The observation that TSH administration caused the intracellular level of cAMP to increase in both TSHr-FlAsH-transfected cell types indicated that the FlAsH binding motif did not alter normal TSHr functioning. When transfected into HeLa cells and stimulated with TSH, the TSHr-FlAsH receptor exhibited a pronounced perinuclear labelling pattern, whereas labelling remained on the cell surface following pre-incubation with 1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane (DDT). Chinese hamster ovary (CHO)-TSHr cells probed with anti-TSHr antibodies were fluorescent mainly in the proximity of the plasma membrane, with fluorescence being primarily restricted to a juxta-nuclear position when exposed to 10 mU/ml TSH for 1 or 5 min. However, in the presence of DDT, the anti-TSHr fluorescence maintained a peripheral location along the cell plasma membrane, even if CHO-TSHr cells were stimulated with TSH for 1 and 5 min. To verify that DDT acted specifically on the TSHr, CHO cells transfected with the A(2)a receptor were used as controls. Following a 1-min stimulation with 5'-(N-ethyl-carboxamido)-adenosine, A(2)a receptors were gradually internalized regardless of the presence of DDT in the culture medium. Finally, immunoelectron microscopy of CHO-TSHr cells showed that a 1-min exposure to TSH sufficed to displace anti-TSHr antibodies tagged with 10-nm gold particles into coated pits and vesicles but that their superficial location was retained along the plasma membrane in the presence of DDT.


Assuntos
DDT/farmacologia , Disruptores Endócrinos/farmacologia , Receptores da Tireotropina/metabolismo , Glândula Tireoide/efeitos dos fármacos , Animais , Células CHO , Células COS , Chlorocebus aethiops , Cricetinae , Cricetulus , Fluorescência , Células HeLa , Humanos , Transporte Proteico/efeitos dos fármacos , Receptores da Tireotropina/genética , Tireotropina/metabolismo , Tireotropina/farmacologia , Transfecção
11.
Eur J Phys Rehabil Med ; 44(4): 449-53, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19002094

RESUMO

Prior to the beginning of this study, the participant (an adolescent with postcoma multiple disabilities) had learned to use a forehead-skin response to access environmental stimuli. These learning data seemed to indicate a minimally conscious state (i.e., awareness of the link between response and stimuli) in spite of 1) a previous diagnosis of postcoma vegetative state; and 2) concomitant electrophysiological measurement showing no evidence of a passive P300 response and of mismatch negativity. The present study was an effort to extend the early learning investigation with two additional responses and related stimuli to broaden learning evidence and ascertain possible choice behavior. Results indicated that the participant learned the new responses and also provided evidence of choice behavior. These data were discussed in terms of the usefulness of the learning paradigm in the assessment and rehabilitation of persons with postcoma multiple disabilities and consciousness disorders.


Assuntos
Pessoas com Deficiência/reabilitação , Estado Vegetativo Persistente/reabilitação , Adolescente , Comportamento de Escolha , Auxiliares de Comunicação para Pessoas com Deficiência , Testa/fisiologia , Humanos , Masculino , Movimento/fisiologia , Estimulação Física
12.
Eur J Neurosci ; 27(11): 2922-7, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18588532

RESUMO

In a recent functional magnetic resonance imaging study, a complex neural circuit was shown to be involved in human males during sexual arousal [A. Ferretti et al. (2005) Neuroimage, 26, 1086]. At group level, there was a specific correlation between penile erection and activations in anterior cingulate, insula, amygdala, hypothalamus and secondary somatosensory regions. However, it is well known that there are remarkable inter-individual differences in the psychological view and attitude to sex of human males. Therefore, a crucial issue is the relationship among cerebral responses, sexual arousal and psychosexual identity at individual level. To address this issue, 18 healthy male subjects were recruited. Their deep sexual identity (DSI) was assessed following the construct revalidation by M. Olivetti Belardinelli [(1994) Sci. Contrib. Gen. Psychol., 11, 131] of the Franck drawing completion test, a projective test providing, according to this revalidation, quantitative scores on 'accordance/non-accordance' between self-reported and psychological sexual identity. Cerebral activity was evaluated by means of functional magnetic resonance imaging during hard-core erotic movies and sport movies. Results showed a statistically significant positive correlation between the blood oxygen level-dependent signal in bilateral hypothalamus and the Franck drawing completion test score during erotic movies. The higher the blood oxygen level-dependent activation in bilateral hypothalamus, the higher the male DSI profile. These results suggest that, in male subjects, inter-individual differences in the DSI are strongly correlated with blood flow to the bilateral hypothalamus, a dimorphic brain region deeply implicated in instinctual drives including reproduction.


Assuntos
Nível de Alerta/fisiologia , Identidade de Gênero , Hipotálamo/fisiologia , Comportamento Sexual/fisiologia , Adulto , Mapeamento Encefálico , Circulação Cerebrovascular/fisiologia , Literatura Erótica/psicologia , Lateralidade Funcional/fisiologia , Humanos , Hipotálamo/irrigação sanguínea , Imageamento por Ressonância Magnética , Masculino , Vias Neurais/anatomia & histologia , Vias Neurais/fisiologia , Testes Neuropsicológicos , Variações Dependentes do Observador , Consumo de Oxigênio/fisiologia , Estimulação Luminosa , Caracteres Sexuais
13.
Cereb Cortex ; 18(5): 1139-47, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-17720687

RESUMO

Several studies have identified a supramodal network critical to the reorienting of attention toward stimuli at novel locations and which involves the right temporoparietal junction and the inferior frontal areas. The present functional magnetic resonance imaging (fMRI)\magnetoencephalography (MEG) study investigates: 1) the cerebral circuit underlying attentional reorienting to spatially varying sound locations; 2) the circuit related to the regular change of sound location in the same hemifield, the change of sound location across hemifields, or sounds presented randomly at different locations on the azimuth plane; 3) functional temporal dynamics of the observed cortical areas exploiting the complementary characteristics of the fMRI and MEG paradigms. fMRI results suggest 3 distinct roles: the supratemporal plane appears modulated by variations of sound location; the inferior parietal lobule is modulated by the cross-meridian effect; and the inferior frontal cortex is engaged by the inhibition of a motor response. MEG data help to elucidate the temporal dynamics of this network by providing high-resolution time series with which to measure latency of neural activation manipulated by the reorienting of attention.


Assuntos
Atenção/fisiologia , Córtex Auditivo/fisiologia , Lobo Frontal/fisiologia , Pericárdio/fisiologia , Localização de Som/fisiologia , Estimulação Acústica , Adulto , Córtex Auditivo/citologia , Mapeamento Encefálico , Potenciais Evocados Auditivos/fisiologia , Feminino , Lobo Frontal/citologia , Humanos , Imageamento por Ressonância Magnética , Magnetoencefalografia , Vias Neurais , Orientação/fisiologia , Pericárdio/citologia , Tempo de Reação/fisiologia
14.
Ann Trop Med Parasitol ; 101(7): 611-9, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17877880

RESUMO

In female phlebotomine sandflies, little is known about the reproductive accessory glands that presumably contribute to egg production and/or oviposition. The main protein secreted in the accessory glands of female Phlebotomus papatasi was recently characterised as a lipase-like protein, the first to be found in the female accessory glands of any insect. This protein, named PhpaLIP (for Phlebotomus papatasi lipase), has now been detected and localized in the reproductive tissues of female P. papatasi, at different stages of the gonotrophic cycle, using a polyclonal anti-PhpaLIP serum and both confocal scanning laser and immuno-electron microscopy. PhpaLIP appears to be always present in the accessory glands (with a secretory peak shortly before oviposition) but was also detected in the follicle cells of the ovarioles, within the developing vitelline envelope, and in the oviducts. The results are discussed in relation to the functions that PhpaLIP could have during the gonotrophic cycle, in the various reproductive structures of female P. papatasi.


Assuntos
Proteínas de Insetos/análise , Lipase/análise , Phlebotomus , Animais , Feminino , Genitália Feminina/enzimologia , Oviposição , Phlebotomus/anatomia & histologia , Reprodução/fisiologia
15.
Brain Res Bull ; 72(4-6): 284-92, 2007 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-17452288

RESUMO

Brain network modeling is probably the biggest challenge in fMRI data analysis. Higher cognitive processes in fact, rely on complex dynamics of temporally and spatially segregated brain activities. A number of different techniques, mostly derived from paradigmatic hypothesis-driven methods, have been successfully applied for such purpose. This paper instead, presents a new data-driven analysis approach that applies both independent components analysis (ICA) and the Granger causality (GC). The method includes two steps: (1) ICA is used to extract the independent functional activities; (2) the GC is applied to the independent component (IC) most correlated with the stimuli, to indicate its functional relation with other ICs. This new method is applied to the analysis of fMRI study of listening to high-frequency trisyllabic words, non-words and reversed words. As expected, activity was found in the primary and secondary auditory cortices. Additionally, a parieto-frontal network of activations, supported by temporal and causality relationships, was found. This network is modulated by experimental conditions in agreement with the most recent models presented for word perception. The results have confirmed the validity of the proposed method, and seem promising for the detection of cognitive causal relationships in neuroimaging data.


Assuntos
Mapeamento Encefálico , Córtex Cerebral/fisiologia , Audição/fisiologia , Rede Nervosa/fisiologia , Análise de Componente Principal , Estimulação Acústica , Análise de Variância , Auscultação , Causalidade , Córtex Cerebral/irrigação sanguínea , Humanos , Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Modelos Neurológicos , Rede Nervosa/irrigação sanguínea , Análise de Regressão
16.
Neuroimage ; 33(2): 672-80, 2006 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-16934491

RESUMO

Similar "what/where" functional segregations have been proposed for both visual and auditory cortical processing. In this fMRI study, we investigated if the same segregation exists in the crossmodal domain, when visual and auditory stimuli have to be matched in order to perform either a recognition or a localization task. Recent neuroimaging research highlighted the contribution of different heteromodal cortical regions during various forms of crossmodal binding. Interestingly, crossmodal effects during audiovisual speech and object recognition have been found in the superior temporal sulcus, while crossmodal effects during the execution of spatial tasks have been found over the intraparietal sulcus, suggesting an underlying "what/where" segregation. In order to directly compare the specific involvement of these two heteromodal regions, we scanned ten male right-handed subjects during the execution of two crossmodal matching tasks. Participants were simultaneously presented with a picture and an environmental sound, coming from either the same or the opposite hemifield and representing either the same or a different object. The two tasks required a manual YES/NO response respectively about location or semantic matching of the presented stimuli. Both group and individual subject analysis were performed. Task-related differences in BOLD response were observed in the right intraparietal sulcus and in the left superior temporal sulcus, providing a direct confirmation of the "what-where" functional segregation in the crossmodal audiovisual domain.


Assuntos
Percepção Auditiva , Mapeamento Encefálico/métodos , Imageamento por Ressonância Magnética/métodos , Localização de Som/fisiologia , Percepção Espacial/fisiologia , Percepção Visual , Estimulação Acústica , Adulto , Lateralidade Funcional , Humanos , Masculino , Estimulação Luminosa , Tempo de Reação , Reconhecimento Psicológico , Fala
17.
Eur J Neurosci ; 24(3): 955-8, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16930423

RESUMO

Learning a musical piece requires the development of a strong linkage between sensory and motor representations. Audition plays a central role and a tight cortical auditory-motor corepresentation is a characteristic feature of music processing. Recent works have indicated the establishment of a functional connection between auditory and motor cortices during the learning of a novel piece, although no causal relation has yet been demonstrated. Here transcranial magnetic stimulation of the cortical motor representation involved in musical performance was used to test excitability changes in piano players during auditory presentation of a rehearsed and a non-rehearsed piece. Results showed an increased motor excitability for the rehearsed but not for the non-rehearsed piece. Moreover, we observed an increase of excitability over time as intracortical facilitation was already present after 30 min of training whereas cortico-spinal facilitation increased after a longer training period (5 days).


Assuntos
Percepção Auditiva/fisiologia , Aprendizagem/fisiologia , Córtex Motor/fisiologia , Movimento/fisiologia , Plasticidade Neuronal/fisiologia , Desempenho Psicomotor/fisiologia , Estimulação Acústica/métodos , Adulto , Córtex Auditivo/fisiologia , Potencial Evocado Motor/fisiologia , Feminino , Humanos , Masculino , Memória/fisiologia , Música/psicologia , Vias Neurais/fisiologia , Tratos Piramidais/fisiologia , Fatores de Tempo , Estimulação Magnética Transcraniana
18.
Ann Trop Med Parasitol ; 99(7): 673-82, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16212801

RESUMO

The reproductive accessory glands of the adult female have a functional versatility in insects, contributing to reproduction in various ways. The major protein secreted by the accessory glands of female Phlebotomus papatasi (Diptera, Psychodidae) has already been characterised and named PhpaLIP (for P. papatasi lipase) because, in terms of its amino-acid sequence, it is very similar to a wide range of vertebrate lipases. The gene coding for PhpaLIP has now been cloned into a pQE30 vector and expressed in Escherichia coli. When the recombinant PhpaLIP was tested in vitro, it was found to have not only lipase-like activity (when p-nitrophenyl caprylate was used as the substrate) but also specific antibacterial activity against some Gram-positive and Gram-negative bacteria. The possible physiological roles of PhpaLIP in P. papatasi are discussed, in the light of these results.


Assuntos
Antibacterianos/metabolismo , Hidrolases de Éster Carboxílico/metabolismo , Genitália Feminina/metabolismo , Phlebotomus/metabolismo , Actinomycetales/metabolismo , Animais , Antibacterianos/isolamento & purificação , Bacillus/metabolismo , Hidrolases de Éster Carboxílico/análise , Hidrolases de Éster Carboxílico/isolamento & purificação , Escherichia coli/metabolismo , Feminino , Insetos Vetores/metabolismo , Testes de Sensibilidade Microbiana/métodos , Pseudomonas/metabolismo , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/metabolismo
19.
Hum Brain Mapp ; 26(4): 251-61, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15954141

RESUMO

Recent animal and human studies indicate the existence of a neural pathway for sound localization, which is similar to the "where" pathway of the visual system and distinct from the sound identification pathway. This study sought to highlight this pathway using a passive listening protocol. We employed fMRI to study cortical areas, activated during the processing of sounds coming from different locations, and MEG to disclose the temporal dynamics of these areas. In addition, the hypothesis of different activation levels in the right and in the left hemispheres, due to hemispheric specialization of the human brain, was investigated. The fMRI results indicate that the processing of sound, coming from different locations, activates a complex neuronal circuit, similar to the sound localization system described in monkeys known as the auditory "where" pathway. This system includes Heschl's gyrus, the superior temporal gyrus, the supramarginal gyrus, and the inferior and middle frontal lobe. The MEG analysis allowed assessment of the timing of this circuit: the activation of Heschl's gyrus was observed 139 ms after the auditory stimulus, the peak latency of the source located in the superior temporal gyrus was at 156 ms, and the inferior parietal lobule and the supramarginal gyrus peaked at 162 ms. Both hemispheres were found to be involved in the processing of sounds coming from different locations, but a stronger activation was observed in the right hemisphere.


Assuntos
Vias Auditivas/anatomia & histologia , Vias Auditivas/fisiologia , Córtex Cerebral/anatomia & histologia , Córtex Cerebral/fisiologia , Potenciais Evocados Auditivos/fisiologia , Localização de Som/fisiologia , Estimulação Acústica , Adulto , Córtex Auditivo/anatomia & histologia , Córtex Auditivo/fisiologia , Mapeamento Encefálico , Feminino , Lobo Frontal/anatomia & histologia , Lobo Frontal/fisiologia , Lateralidade Funcional/fisiologia , Humanos , Imageamento por Ressonância Magnética , Magnetoencefalografia , Masculino , Lobo Parietal/anatomia & histologia , Lobo Parietal/fisiologia , Tempo de Reação/fisiologia
20.
Insect Mol Biol ; 12(5): 501-8, 2003 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12974955

RESUMO

A lipase-like protein (PhpaLIP) was identified as the major protein component in the secretion of the female reproductive accessory glands of the sand fly Phlebotomus papatasi. The full-length cDNA encoding this protein was isolated and its nucleotide sequence determined. The deduced translational product of the gene contains a GFSFG motif, consistent with a GXSXG consensus, which is shared by most bacterial and eukaryotic hydrolases. Transcriptional analysis of the PhpaLIP gene showed that its expression is female-specific, and is also detectable in districts other than accessory glands, suggesting that it might play different functions. Taken together with the observation of sequence similarity shared by PhpaLIP and mammalian lipases, the demonstration of the presence of lipase activity in the accessory gland secretion suggests a possible biological role of PhpaLIP gene product.


Assuntos
DNA Complementar/genética , Genitália Feminina/metabolismo , Lipase/genética , Phlebotomus/genética , Animais , Sequência de Bases , Primers do DNA , Eletroforese em Gel de Poliacrilamida , Feminino , Dados de Sequência Molecular , Phlebotomus/enzimologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Alinhamento de Sequência , Análise de Sequência de DNA , Espectrofotometria , Transcrição Gênica/genética
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