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10962. Toxoplasma gondii strain-dependent effects on mouse behaviour
- Creator:
- Kannan, Geetha, Moldovan, Krisztina, Xiao, Jian-Chun, Yolken, Robert H., Jones-Brando, Lorraine, and Pletnikov, Mikhail V.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Toxoplasma, behaviour, and strain dependency
- Language:
- English
- Description:
- Toxoplasma gondii reportedly manipulates rodent behaviour to increase transmission to its definitive feline host. We compared the effects of mouse infection by two Type II strains of T. gondii, Prugniaud (PRU) and ME49, on attraction to cat odour, locomotor activity, anxiety, sensorimotor gating, and spatial working and recognition memory 2 months post-infection (mpi). Attraction to cat odour was reassessed 7 mpi. At 2 mpi, mice infected with either strain exhibited significantly more attraction to cat odour than uninfected animals did, but only PRU-infected mice exhibited this behaviour 7 mpi. PRU-infected mice had significantly greater body weights and hyperactivity, while ME49-infected mice exhibited impaired spatial working memory. No differences in parasite antibody titres were seen between PRU- and ME49-infected mice. The present data suggest the effect of T. gondii infection on mouse behaviour is parasite strain-dependent.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
10963. Toxoplasma gondii-altered host behaviour: clues as to mechanism of action
- Creator:
- Webster, Joanne P. and McConkey, Glenn A.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Toxoplasma gondii, rodents, behaviour, schizophrenia, mechanisms, and dopamine
- Language:
- English
- Description:
- A convincing body of evidence now exists, from both human and animal studies, and encompassing epidemiological to experimental, to indicate that the common protozoan Toxoplasma gondii can cause specific behavioural changes in its host. Such behavioural alterations are likely to be the product of strong selective pressures for the parasite to enhance transmission from its intermediate host reservoir, primarily rodent, to its feline definitive host, wherein sexual reproduction can occur and the parasite's life cycle completed. Here we consider what the available data to date may reveal about the potential mechanisms involved, the future research that needs to be performed, and the subsequent implications for animal and human health.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
10964. Toxoplasmosis as a cause for behaviour disorders - overview of evidence and mechanisms
- Creator:
- Fekadu, Abebaw, Shibre, Teshome, and Cleare, Anthony J.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- toxoplasmosis, Toxoplasma gondii, behavioural disorder, personality changes, schizophrenia, mood disorders, and review
- Language:
- English
- Description:
- Background - There is growing interest in the role of microbial agents in the causation of psychiatric disorders. The neurotropic protozoan parasite Toxoplasma gondii is one of the main candidates and has been associated with various psychiatric conditions, including schizophrenia. Methods - A narrative review of the literature from the main medical databases (Medline, PubMed, PsycINFO), Google Scholar and Google using combinations of applicable terms. Results - T. gondii affects the brain in both the acute and the latent stages of infection causing apparent brain pathologies in infected rodents and both immuno-compromised and immuno-competent humans. In immuno-competent individuals, behavioural disorders are primarily related to the latent stages of the illness. Behavioural/mental disorders that include schizophrenia, mood disorders, personality changes and cognitive impairments may be related to infection with T. gondii. Evidence for a behavioural effect of T. gondii comes from observational reports in animal models and controlled behavioural analysis in humans. Indirect clues of infection also come from raised seroprevalence or serotitres of antitoxoplasma antibodies among those with mental disorders. The pathophysiologic mechanism through which T. gondii may exert its effect is not clear, but direct impact on the brain and changes in neuroimmunomodulation, neurotransmission and some gene-environment interactions are postulated. Conclusion - There is evidence supporting a potential role of T. gondii infection in the onset of some behavioural disorders. Confirmation of such a role would prove a significant breakthrough in the search for the aetiology, treatment and prevention of behavioural disorders, such as schizophrenia. However, the associations remain preliminary.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
10965. Trace elements have beneficial, as well as detrimental effects on bone homeostasis
- Creator:
- Ivana Žofková, Davis, M., and Jaroslav Blahoš
- Format:
- print, bez média, and svazek
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, bor, kadmium, měď, železo, olovo, hořčík, mangan, selen, zinek, boron, cadmium, copper, iron, lead, magnesium, manganese, selenium, zinc, bone mineral density, bone quality, fluoride, 14, and 612
- Language:
- English
- Description:
- The protective role of nutrition factors such as calcium, vitamin D and vitamin K for the integrity of the skeleton is well understood. In addition, integrity of the skeleton is positively influenced by certain trace elements (e.g. zinc, copper, manganese, magnesium, iron, selenium, boron and fluoride) and negatively by others (lead, cadmium, cobalt). Deficiency or excess of these elements influence bone mass and bone quality in adulthood as well as in childhood and adolescence. However, some protective elements may become toxic under certain condition s, depending on dosage (serum concentration), duration of treatment and interactions among individual elements. We review the beneficial and toxic effects of key elements on bone homeostasis., I. Zofkova, M. Davis, J. Blahos., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
10966. Traceless component of the conformal curvature tensor in Kähler manifold.
- Creator:
- Funabashi, Shoichi, Kim, Hyang Sook, Kim, Young-Mi, and Pak, Jin Suk
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Kähler manifold, conformal tensor field, trace decomposition, concircular transformation, and spectrum
- Language:
- English
- Description:
- We investigate the traceless component of the conformal curvature tensor defined by (2.1) in Kähler manifolds of dimension $\ge 4$, and show that the traceless component is invariant under concircular change. In particular, we determine Kähler manifolds with vanishing traceless component and improve some theorems (for example, [4, pp. 313–317]) concerning the conformal curvature tensor and the spectrum of the Laplacian acting on $p$ $(0\le p\le 2)$-forms on the manifold by using the traceless component.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
10967. Traces of anisotropic Besov-Lizorkin-Triebel spaces-a complete treatment of the borderline cases
- Creator:
- Farkas, Walter, Johnsen, Jon, and Sickel, Winfried
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- anisotropic Besov and Lizorkin-Triebel spaces, approximation spaces, trace operators, boundary problems, interpolation, atomic decompositions, refined Sobolev embeddings, and anisotropic scales
- Language:
- English
- Description:
- Including the previously untreated borderline cases, the trace spaces (in the distributional sense) of the Besov-Lizorkin-Triebel spaces are determined for the anisotropic (or quasi-homogeneous) version of these classes. The ranges of the traces are in all cases shown to be approximation spaces, and these are shown to be different from the usual spaces precisely in the cases previously untreated. To analyse the new spaces, we carry over some real interpolation results as well as the refined Sobolev embeddings of J. Franke and B. Jawerth to the anisotropic scales.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
10968. Traces of functions with a dominating mixed derivative in $\Bbb R^3$
- Creator:
- Vybíral, Jan and Sickel, Winfried
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Sobolev spaces of dominating mixed smoothness, Besov and Lizorkin-Triebel classes of dominating mixed smoothness, Fourier analytic characterizations, atomic decompositions, and traces on hyperplanes in oblique position
- Language:
- English
- Description:
- We investigate traces of functions, belonging to a class of functions with dominating mixed smoothness in ${\mathbb{R}}^3$, with respect to planes in oblique position. In comparison with the classical theory for isotropic spaces a few new phenomenona occur. We shall present two different approaches. One is based on the use of the Fourier transform and restricted to $p=2$. The other one is applicable in the general case of Besov-Lizorkin-Triebel spaces and based on atomic decompositions.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
10969. Traces of reality: alternative realisms in Taiwan during the 1960s and 1970s
- Creator:
- Storm, Carsten
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Taiwan, realism, modernism, nativism, and literary theory
- Language:
- English
- Description:
- In Taiwanese literature, as in many other national literatures, realism is a term which has been used to serve many aims. Aesthetic and narrative aspects contribute to realism as much as poliical, ideological and/or social convictions. In Taiwam, it has been used as a label by almost all literary groups and schools since the first wave of native literature (xiangtu wenxue) in the 1920s in order to describe and ligitimize their respective literary and - frequently - political claims. Over time, the very meaning of the term "realism" had been subject to multiple changes, thus turning "realism" into an almost empty signifier that needed to be further framed. Realism increasingly tended to be accompanied by an explanatory adjunct, specifying what kind of realism was indicated. The article re-evaluates epistemological issues connected to the use of realism among Taiwan´s modernists and nativists in the 1960s and 1970s. It argues that the struggle between both groups is primarily in relation to the appropriate adjunct to be attached to realism. Both movements illustrate how realism has grown into a meta-term of modernity, while its aesthetics, subject matter, and ethical impact have became increasingly vague.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
10970. Tracking control design for nonlinear polynomial systems via augmented error system approach and block pulse functions technique
- Creator:
- Warrad, Bassem Iben, Bouafoura , Mohamed Karim, and Braiek, Naceur Benhadj
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- tracking control, nonlinear polynomial systems, augmented error system approach, block pulse functions, and practical stability
- Language:
- English
- Description:
- In this paper, tracking control design for a class of nonlinear polynomial systems is investigated by augmented error system approach and block pulse functions technique. The proposed method is based on the projection of the close loop augmented system and the associated linear reference model that it should follow over a basis of block pulse functions. The main advantage of using this tool is that it allows to transform the analytical differential calculus into an algebraic one relatively easy to solve. The developments presented have led to the formulation of a linear system of algebraic equations depending only on parameters of the feedback control. Once the control gains are determined by solving the latter optimization problem in least square sense, the practical stability of the closed loop augmented system is checked through given conditions. A double inverted pendulums benchmark is used to validate the proposed tracking control method.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public