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1.
Vet Microbiol ; 162(2-4): 643-651, 2013 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-23266108

RESUMO

The severity of swine influenza is highly variable and can be exacerbated by many factors, such as a pre-infection of pigs with Mycoplasma hyopneumoniae (Mhp). The aim of this study was to investigate the oxidative stress induced by Mhp and the impact of this stress on the evolution of an infection with the European avian-like swine H1N1 influenza virus. Two experimental trials (E1 and E2), which differed only by the feed delivered to the animals, were conducted on SPF pigs. In each trial, one group of nine 6-week-old pigs was inoculated intra-tracheally with Mhp and H1N1 at 21 days intervals and a mock-infected group (8 pigs) was included. Clinical signs were observed, blood samples were collected throughout the study and pathogens were detected in nasal swabs and lung tissues. Results indicated that Mhp infection induced an oxidative stress in E1 and E2, but its level was more important in E2 than in E1 three weeks post-Mhp inoculation, before H1N1 infection. In both trials, a strong inflammatory response and a response to the oxidative stress previously induced by Mhp appeared after H1N1 infection. However, the severity of influenza disease was significantly more marked in E2 as compared to E1, as revealed by prolonged hyperthermia, stronger reduction in mean daily weight gain and earlier viral shedding. These results suggested that severity of flu syndrome and reduction in animal performance may vary depending on the level of oxidative stress at the moment of the influenza infection, and that host responses could be influenced by the feed.


Assuntos
Vírus da Influenza A Subtipo H1N1/metabolismo , Mycoplasma hyopneumoniae/metabolismo , Infecções por Orthomyxoviridae/veterinária , Estresse Oxidativo/fisiologia , Doenças dos Suínos/metabolismo , Doenças dos Suínos/microbiologia , Animais , Humanos , Influenza Humana , Pulmão/virologia , Infecções por Orthomyxoviridae/metabolismo , Infecções por Orthomyxoviridae/virologia , Sus scrofa , Suínos , Doenças dos Suínos/virologia , Eliminação de Partículas Virais
2.
Gynecol Obstet Fertil ; 40(12): 787-96, 2012 Dec.
Artigo em Francês | MEDLINE | ID: mdl-23177978

RESUMO

Worldwide statistics agree that at least one out of six couples has fertility problems. If the male gamete is the origin of this problem, it is generally admitted that the oxidative stress is involved. Modern life has obviously increased fertility problems through pesticides, xenoestrogenes, endocrine disrupting chemicals involved in plastic technology such as polychlorinated bisphenyls, bisphenol A, phthalates and alkylphenols… and other cosmetic additives. An important part of these compounds increases oxidative stress, at least in part. Oxidative stress is more than probably at the origin or recurrent increasing pathologies such as endometriosis. If the oocyte is theoretically able to repair oxidative stress linked decays such as DNA fragmentation and oxidation of bases, its capacity is finite and decreasing with age. In order to decrease DNA repair charge, reducing or even avoiding the generation of DNA damages related to reactive oxygen species through consumption of antioxidants compounds is often tempting: however Reasons will be provided to break from current treatments given haphazardly in the population in the age of reproduction, as well as the potential risks of over-exposure. Furthermore recommended treatments, in relation with the new concepts in oxidative stress, will be specified.


Assuntos
Infertilidade/etiologia , Estresse Oxidativo , Antioxidantes/administração & dosagem , Antioxidantes/efeitos adversos , Ácido Ascórbico/administração & dosagem , Dano ao DNA , Reparo do DNA , Suplementos Nutricionais , Feminino , Humanos , Infertilidade Feminina/etiologia , Infertilidade Masculina/etiologia , Masculino , Oócitos/fisiologia , Selênio/administração & dosagem , Espermatozoides/fisiologia , Superóxido Dismutase , Ubiquinona/administração & dosagem , Ubiquinona/análogos & derivados
3.
Phys Rev E Stat Nonlin Soft Matter Phys ; 81(1 Pt 1): 011118, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20365334

RESUMO

We investigate the particle and kinetic-energy densities for a system of N fermions bound in a local (mean-field) potential V(r) . We generalize a recently developed semiclassical theory [J. Roccia and M. Brack, Phys. Rev. Lett. 100, 200408 (2008)] in which the densities are calculated in terms of the closed orbits of the corresponding classical system to D>1 dimensions. We regularize the semiclassical results (i) for the U(1) symmetry breaking occurring for spherical systems at r=0 and (ii) near the classical turning points where the Friedel oscillations are predominant and well reproduced by the shortest orbit going from r to the closest turning point and back. For systems with spherical symmetry, we show that there exist two types of oscillations which can be attributed to radial and nonradial orbits, respectively. The semiclassical theory is tested against exact quantum-mechanical calculations for a variety of model potentials. We find a very good overall numerical agreement between semiclassical and exact numerical densities even for moderate particle numbers N . Using a "local virial theorem," shown to be valid (except for a small region around the classical turning points) for arbitrary local potentials, we can prove that the Thomas-Fermi functional tau(TF)[rho] reproduces the oscillations in the quantum-mechanical densities to first order in the oscillating parts.

4.
Redox Rep ; 14(1): 23-33, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19161675

RESUMO

Oxidative stress is implicated in the development of a wide range of chronic human diseases, ranging from cardiovascular to neurodegenerative and inflammatory disorders. As oxidative stress results from a complex cascade of biochemical reactions, its quantitative prediction remains incomplete. Here, we describe a machine-learning approach to the prediction of levels of oxidative stress in human subjects. From a database of biochemical analyses of oxidative stress biomarkers in blood, plasma and urine, non-linear models have been designed, with a statistical methodology that includes variable selection, model training and model selection. Our data demonstrate that, despite a large inter- and intra-individual variability, levels of biomarkers of oxidative damage in biological fluids can be predicted quantitatively from measured concentrations of a limited number of exogenous and endogenous antioxidants.


Assuntos
Antioxidantes/análise , Inteligência Artificial , Biomarcadores/sangue , Estresse Oxidativo , Doenças Cardiovasculares/sangue , Doenças Cardiovasculares/patologia , Doença Crônica , Feminino , Humanos , Inflamação/sangue , Inflamação/patologia , Masculino , Modelos Biológicos , Doenças Neurodegenerativas/sangue , Doenças Neurodegenerativas/patologia
5.
Phys Rev E Stat Nonlin Soft Matter Phys ; 70(1 Pt 2): 016206, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15324151

RESUMO

In nonintegrable Hamiltonian systems with mixed phase space and discrete symmetries, sequences of pitchfork bifurcations of periodic orbits pave the way from integrability to chaos. In extending the semiclassical trace formula for the spectral density, we develop a uniform approximation for the combined contribution of pitchfork bifurcation pairs. For a two-dimensional double-well potential and the familiar Hénon-Heiles potential, we obtain very good agreement with exact quantum-mechanical calculations. We also consider the integrable limit of the scenario which corresponds to the bifurcation of a torus from an isolated periodic orbit. For the separable version of the Hénon-Heiles system we give an analytical uniform trace formula, which also yields the correct harmonic-oscillator SU(2) limit at low energies, and obtain excellent agreement with the slightly coarse-grained quantum-mechanical density of states.

6.
Phys Rev E Stat Nonlin Soft Matter Phys ; 70(6 Pt 2): 066208, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15697485

RESUMO

We investigate the resonance spectrum of the Hénon-Heiles potential up to twice the barrier energy. The quantum spectrum is obtained by the method of complex coordinate rotation. We use periodic orbit theory to approximate the oscillating part of the resonance spectrum semiclassically and Strutinsky smoothing to obtain its smooth part. Although the system in this energy range is almost chaotic, it still contains stable periodic orbits. Using Gutzwiller's trace formula, complemented by a uniform approximation for a co-dimension-two bifurcation scenario, we are able to reproduce the coarse-grained quantum-mechanical density of states very accurately, including only a few stable and unstable orbits.

7.
Phys Rev Lett ; 89(11): 116601, 2002 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-12225159

RESUMO

We formulate a semiclassical theory for systems with spin-orbit interactions. Using spin coherent states, we start from the path integral in an extended phase space, formulate the classical dynamics of the coupled orbital and spin degrees of freedom, and calculate the ingredients of Gutzwiller's trace formula for the density of states. For a two-dimensional quantum dot with a spin-orbit interaction of Rashba type, we obtain satisfactory agreement with fully quantum-mechanical calculations. The mode-conversion problem, which arose in an earlier semiclassical approach, has hereby been overcome.

8.
J Neurol Neurosurg Psychiatry ; 70(6): 794-7, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11385017

RESUMO

Primary CNS lymphomas are detected with increasing frequency in immunocompetent and immunodeficient persons. Primary involvement of the spinal roots has only rarely been reported. The unusual history is described of a patient with a primary spinal Burkitt's lymphoma initially presenting as an S1 syndrome showing lymphocytic pleocytosis in the CSF, leading to the misdiagnosis of meningoradiculitis. Repeated spinal MRI disclosed a spinal mass lesion and histological and immunohistological examination of the tumour confirmed the diagnosis of spinal Burkitt's lymphoma.


Assuntos
Linfoma de Burkitt/líquido cefalorraquidiano , Linfoma de Burkitt/patologia , Medula Espinal/patologia , Adulto , Feminino , Humanos , Imageamento por Ressonância Magnética
9.
Phys Rev E Stat Nonlin Soft Matter Phys ; 63(6 Pt 2): 065201, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11415159

RESUMO

We have derived a semiclassical trace formula for the level density of the three-dimensional spheroidal cavity. To overcome the divergences occurring at bifurcations and in the spherical limit, the trace integrals over the action-angle variables were performed using an improved stationary phase method. The resulting semiclassical level density oscillations and shell-correction energies are in good agreement with quantum-mechanical results. We find that the bifurcations of some dominant short periodic orbits lead to an enhancement of the shell structure for "superdeformed" shapes related to those known from atomic nuclei.

10.
Phys Rev Lett ; 86(8): 1574-7, 2001 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-11290196

RESUMO

We derive simple analytical expressions for the particle density rho(r) and the kinetic energy density tau(r) for a system of noninteracting fermions in a d-dimensional isotropic harmonic oscillator potential. We test the Thomas-Fermi (TF, or local-density) approximation for the functional relation tau[rho] using the exact rho(r) and show that it locally reproduces the exact kinetic energy density tau(r), including the shell oscillations, surprisingly well everywhere except near the classical turning point. For the special case of two dimensions (2D), we obtain the unexpected analytical result that the integral of tau(TF)[rho(r)] yields the exact total kinetic energy.

11.
J Med Primatol ; 30(6): 322-7, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11990532

RESUMO

Cotton-top tamarins are well known for their prevalence to idiopathic colitis and adenocarcinomas. At the same time, information on the incidence of spontaneous lymphomas in this highly endangered species is rare. Records, 212 in total, of cotton-top tamarins (Saguinus oedipus) necropsied at the German Primate Centre between 1979 and 1998 were viewed to establish the prevalence of lymphoid neoplasms. Neoplastic lymphoid cell growth was mentioned in three necropsy records. Immunohistology was performed in all three cases on the remaining formalin-fixed, paraffin-embedded tissue using antibodies against CD20, CD3, lysozyme, Ki-67, IgM, IgG, kappa, lambda and EBNA-2. Combining histological and immunohistological results, the lymphomas could be differentiated into two low-grade T-cell lymphomas and one high-grade multicentric polymorphic B-cell lymphoma. This corresponds to a 1.4% incidence of lymphomas in our cotton-top tamarin population over a period of 19 years. Although frozen material was not available and virological testing could not be carried out, clinical or histological evidence did not support an aetiological role of Herpes (H.) saimiri, H. ateles, simian T-cell leukaemia virus type 1 (STLV-1) or Epstein-Barr-related herpesvirus in any of these cases. The lymphomas were considered to be spontaneous.


Assuntos
Linfoma de Células B/patologia , Linfoma de Células T/patologia , Doenças dos Macacos/patologia , Saguinus , Animais , Feminino , Incidência , Linfoma de Células B/diagnóstico , Linfoma de Células B/veterinária , Linfoma de Células T/diagnóstico , Linfoma de Células T/veterinária , Doenças dos Macacos/diagnóstico , Estudos Retrospectivos
13.
Comp Med ; 50(2): 212-7, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10857013

RESUMO

BACKGROUND AND PURPOSE: The sexual activity of male tree shrews is socially influenced; therefore, the testicular lesions in adult male tree shrews were of interest. METHODS: The testes of 229 adult and 9 subadult male tree shrews were obtained during routine necropsy and were subjected to light microscopy. At one time, 138 animals were experimentally exposed to social conflicts. RESULTS: Hypospermatogenesis (testicular inactivity) was observed in social stress-exposed males up to two years of age. Seasonality of hypospermatogenesis could not be statistically supported. Testicular atrophy, observed in 21 animals, was neither stress- nor age-related; it developed unilaterally, with the left testis preferred. Testicular tumors developed in animals older than 2 years, with increasing frequency particularly of Leydig cell tumors in animals more than four year old. CONCLUSION: Testicular lesions were more frequently found in male tree shrews than they were observed in nonhuman primates kept at the German Primate Center. Connections to social stress were statistically supported, particularly with respect to hypospermatogenesis. Testicular tumors, in contrast, were distinctly age related.


Assuntos
Doenças Testiculares/etiologia , Doenças Testiculares/patologia , Neoplasias Testiculares/patologia , Testículo/patologia , Tupaia , Fatores Etários , Animais , Atrofia/etiologia , Atrofia/patologia , Dominação-Subordinação , Hamartoma/etiologia , Hamartoma/patologia , Incidência , Tumor de Células de Leydig/etiologia , Tumor de Células de Leydig/patologia , Masculino , Necrose , Oligospermia/etiologia , Oligospermia/patologia , Estudos Retrospectivos , Estações do Ano , Seminoma/etiologia , Seminoma/patologia , Tumor de Células de Sertoli/etiologia , Tumor de Células de Sertoli/patologia , Espermatogênese/fisiologia , Estresse Fisiológico/patologia , Neoplasias Testiculares/etiologia
14.
Lab Anim ; 34(1): 106-10, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10759374

RESUMO

Two adrenal gland tumours in captive born cotton-top tamarins (Saguinus oedipus oedipus) are described. One was a pheochromocytoma in a 14-year-old male, the other one a cortical adenoma in a 7.5-year-old female. Both were associated with morphological signs of myocardial damage and circulatory problems. The findings are discussed and compared to adrenal gland tumours in man.


Assuntos
Neoplasias das Glândulas Suprarrenais/veterinária , Saguinus , Neoplasias das Glândulas Suprarrenais/patologia , Animais , Feminino , Masculino , Feocromocitoma/patologia , Feocromocitoma/veterinária
15.
Mov Disord ; 14(4): 681-3, 1999 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10435508

RESUMO

We examined 57 patients with idiopathic torsion dystonia (ITD) for the 3-bp GAG deletion in the DYT1 gene on human chromosome 9q34. Three of five patients with early limb-onset ITD, one of them with a positive family history, tested positive for the mutation, as did one young patient with multifocal dystonia and a short course of the disease. Two patients with early-onset generalized dystonia beginning in the cervical muscles, as well as five other patients with multifocal, 14 patients with segmental, and 30 patients with focal cervical dystonia did not carry the mutation. This suggests that the GAG deletion is responsible for a major portion of cases of typical early limb-onset dystonia, but not for other types of dystonia, in our population.


Assuntos
Proteínas de Transporte/genética , Cromossomos Humanos Par 9 , Distonia/genética , Extremidades , Deleção de Genes , Chaperonas Moleculares , Adolescente , Adulto , Idade de Início , Idoso , Criança , Progressão da Doença , Distonia/classificação , Saúde da Família , Feminino , Marcadores Genéticos , Alemanha , Haplótipos , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo de Fragmento de Restrição
16.
Nephron ; 82(3): 221-31, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10395994

RESUMO

Renal tissues of callitrichids with IgM nephropathy were immunohistochemically examined for the participation of IgA in pathogenesis. In 58 histopathologically nephropathy-positive kidneys, IgM predominated in 20 cases and IgA in 7 cases, and in 31 cases both immunoglobulins were rated to be approximately equally involved. The disease, therefore, might be described as IgM/IgA nephropathy. The renal tissues and sera were also tested for nutritional antigens or antinutritional antigen antibodies, using immunohistochemistry and Western blots (tissues) and enzyme-linked immunosorbent assay (sera). Evidences of nutritional antigens in the renal tissues were inconclusive, although circulating IgG class antibodies against cereals, milk, and egg proteins were present in quite a number of sera. Particular consideration was paid to IgA-antigliadin antibodies, which were statistically significantly associated with nephropathy as were IgA rheumatoid factors. The findings are discussed in relation to human IgA and IgM nephropathies.


Assuntos
Callitrichinae/imunologia , Glomerulonefrite por IGA/patologia , Imunoglobulina M/imunologia , Doenças dos Macacos/patologia , Animais , Antígenos/imunologia , Alimentos , Gliadina/sangue , Gliadina/imunologia , Mesângio Glomerular/imunologia , Mesângio Glomerular/patologia , Imunoglobulina A/sangue , Imunoglobulina A/imunologia , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Imuno-Histoquímica , Rim/imunologia , Rim/patologia , Fator Reumatoide/sangue , Fator Reumatoide/imunologia
17.
J Comp Pathol ; 119(2): 183-8, 1998 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9749363

RESUMO

Adrenal cysts of epithelial origin were found incidentally in the adrenal cortical tissues of two adult female saddleback tamarins. In one case, a small cluster of minor cysts was located at the cortico-medullary border. The cysts were filled with a periodic acid-Schiff (PAS)-positive, amorphous substance and lined by a cuboidal PAS-negative epithelium, which resembled morphologically the ascending Henle's loops of the kidney. These microcysts were thought to be mesonephric remnants. In the second case, two large cysts of 1 to 3 mm diameter extended throughout the entire cortex. The cysts were filled by a watery, PAS-negative fluid and lined by a bi- to multi-layered, cytokeratin-positive epithelium. The basal epithelial layer consisted of cuboidal cells, which became cylindrical to drop-like in appearance towards the cyst lumen. The cysts closely resembled mesothelium-derived adrenal cysts in man. This is the first report of adrenal cysts in non-human primates.


Assuntos
Córtex Suprarrenal/patologia , Doenças das Glândulas Suprarrenais/veterinária , Cistos/veterinária , Doenças dos Macacos/patologia , Saguinus , Doenças das Glândulas Suprarrenais/patologia , Animais , Cistos/patologia , Epitélio/patologia , Feminino , Reação do Ácido Periódico de Schiff/veterinária
18.
J Comp Pathol ; 118(4): 301-16, 1998 May.
Artigo em Inglês | MEDLINE | ID: mdl-9651807

RESUMO

In a necropsy series at the German Primate Centre, 63 of 1132 tree shrews were found to have tumours. The youngest affected animal was < 6 months old, but the incidence of tumours increased strikingly beyond 2 years of age; of 17 animals aged > 8 years, no less than 14 (82.4%) were affected. The sites of neoplasia were the genital system (22 cases), haematopoietic system (18 cases of malignant lymphoma, many involving the digestive tract), lungs (14 cases), integument (five cases), digestive tract (three cases other than those with malignant lymphoma) and urinary bladder (one case).


Assuntos
Neoplasias/epidemiologia , Neoplasias/veterinária , Tupaia , Distribuição por Idade , Animais , Feminino , Neoplasias dos Genitais Femininos/epidemiologia , Neoplasias dos Genitais Femininos/patologia , Neoplasias dos Genitais Femininos/veterinária , Neoplasias dos Genitais Masculinos/epidemiologia , Neoplasias dos Genitais Masculinos/patologia , Neoplasias dos Genitais Masculinos/veterinária , Alemanha/epidemiologia , Incidência , Linfoma/epidemiologia , Linfoma/patologia , Linfoma/veterinária , Masculino , Neoplasias Mamárias Animais/epidemiologia , Neoplasias Mamárias Animais/patologia , Neoplasias/patologia , Neoplasias Primárias Múltiplas/epidemiologia , Neoplasias Primárias Múltiplas/patologia , Neoplasias Primárias Múltiplas/veterinária , Neoplasias do Sistema Respiratório/epidemiologia , Neoplasias do Sistema Respiratório/patologia , Neoplasias do Sistema Respiratório/veterinária , Estudos Retrospectivos
19.
Neurosci Res ; 30(1): 25-34, 1998 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9572577

RESUMO

Event-related brain potentials (ERPs) were recorded from multiple scalp locations from young human subjects while they performed two different face processing tasks. The first task entailed the presentation of pairs of faces in which the second face was either a different view of the first face or a different view of a different face. The subjects had to decide whether or not the two faces depicted the same person. In the second task, pairs of faces (frontal views) were presented with the task of judging whether the expression of the second face matched that of the face. Incongruous faces in the view (identity) matching task gave rise to a negativity peaking at about 350 ms with a frontocentral maximum. This effect was similar to the N400 obtained in linguistic tasks. ERP effects in the expression matching task were much later and had a different distribution. This pattern of results corresponds well with neuropsychological and neuroimaging data suggesting specialized neuronal populations subserving identity and expression analysis but adds a temporal dimension to previous investigations.


Assuntos
Encéfalo/fisiologia , Emoções , Potenciais Evocados Visuais/fisiologia , Face , Expressão Facial , Reconhecimento Visual de Modelos/fisiologia , Adulto , Ira , Feminino , Humanos , Masculino , Sorriso
20.
J Med Primatol ; 27(6): 319-24, 1998 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10203013

RESUMO

Twenty-six gastrointestinal tumors were observed in twenty-three nonhuman primates during routine necropsies at the German Primate Center, Göttingen. The majority (15 cases) were colorectal mucoid adenocarcinomas in cotton-top tamarins (Saguinus oedipus), which in two animals were associated with gastric adenomas. Three cases of small intestinal mucoid adenocarcinomas occurred in common marmosets (Callithrix jacchus). One colonic leiomyoma was observed in a dwarf galago (Galagoides demidovii) and another one in a cotton top tamarin. Singular findings were a tubular adeno-carcinoma of the ileo-caecal valve in a saddle-backed tamarin (Saguinus fuscicollis) and a lymphosarcoma of jejunum, ileum, and colon in another saddle-backed tamarin. Multiple tubular adeno-carcinomas of the colonic diverticles occurred in an aged rhesus monkey (Macaca mulatta). The findings are discussed in comparison to the situation in man.


Assuntos
Neoplasias Gastrointestinais/veterinária , Doenças dos Primatas/epidemiologia , Animais , Callithrix , Carcinoma/epidemiologia , Carcinoma/veterinária , Feminino , Galago , Neoplasias Gastrointestinais/epidemiologia , Neoplasias Gastrointestinais/patologia , Alemanha/epidemiologia , Leiomioma/epidemiologia , Leiomioma/veterinária , Macaca mulatta , Masculino , Doenças dos Primatas/patologia , Saguinus
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