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1.
J West Afr Coll Surg ; 4(4): 39-69, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-27182510

RESUMO

BACKGROUND: Women with breast cancer undergo multimodal treatment for best outcome. This study seeks to identify the treatment challenges for such women in Imo State, Nigeria vis-à-vis similar women in Indiana USA. We compared the treatment modalities of both groups; noting predictors of compliance for subsequent action. SETTING: Federal Medical Centre, Owerri; Imo State, Imo State University, Orlu, Nigeria and Indiana University Hospital, Indiana, USA. DESIGN: A retrospective study. METHODOLOGY: From 2000-2013, 100 randomly pulled charts of patients treated for pathologically confirmed breast cancer in Imo, Nigeria Federal Medical Centre Owerri, Imo State University Hospital; and Indiana University Hospital U.S. respectively were reviewed. The demographics, clinical and pathological data of the patients with confirmed breast cancer were obtained. The data were formatted and analyzed with SPSS version 16.0. The clinical features, management options, outcomes and specific features were compared for both groups using Wilcoxon Rank Sum tests (age, parity) and chi-square tests for all other variables. A 5% significance level was used for all tests. RESULTS: One hundred patients were included for each group. The mean/minimum ages; Imo, Nigeria 41.7/21 (SD/SE 15.3/1.5) vs. Indiana, U.S.56.4/29 (SD 12.4/SE 1.2) p<0.0001. Histology for Indiana USA women was predominantly ductal carcinoma in situ (DCIS) P<0.0001 while that of Imo, Nigeria was invasive ductal carcinoma inflammatory cancer P<0.0326. Women in both locations received chemotherapy and surgery. Imo women received less radiotherapy. Toxicity from chemotherapy remained constant features for both groups, P<0.0001. In Indiana USA, the 5year survival exceeded 85%; In Imo Nigeria it was 10%. This study showed that Women on both locations who were likely to be compliant were those receiving mastectomy; Imo, Nigeria 44(56%) <0.013 vs. Indiana, U.S. 74(80%) p<0.0186; women with cosmesis given; Imo, Nigeria 41(42%) vs. Indiana, U.S. 91 (94%) p<0.0001. Sample sizes were inadequate to perform multivariable models. CONCLUSION: The multimodal treatment regimen implied that there was need for an algorithm protocol for breast cancer women. Thus the need to improve the quality of treatment particularly in Nigeria by improved treatment documentation to overcome key barriers involving information exchange.

2.
Am J Physiol Heart Circ Physiol ; 294(4): H1833-9, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18245564

RESUMO

Shear rate is significantly lower in the superficial femoral compared with the brachial artery in the supine posture. The relative shear rates in these arteries of subjects in the upright posture (seated and/or standing) are unknown. The purpose of this investigation was to test the hypothesis that upright posture (seated and/or standing) would produce greater shear rates in the superficial femoral compared with the brachial artery. To test this hypothesis, Doppler ultrasound was used to measure mean blood velocity (MBV) and diameter in the brachial and superficial femoral arteries of 21 healthy subjects after being in the supine, seated, and standing postures for 10 min. MBV was significantly higher in the brachial compared with the superficial femoral artery during upright postures. Superficial femoral artery diameter was significantly larger than brachial artery diameter. However, posture had no significant effect on either brachial or superficial femoral artery diameter. The calculated shear rate was significantly greater in the brachial (73 +/- 5, 91 +/- 11, and 97 +/- 13 s(-1)) compared with the superficial femoral (53 +/- 4, 39 +/- 77, and 44 +/- 5 s(-1)) artery in the supine, seated, and standing postures, respectively. Contrary to our hypothesis, our current findings indicate that mean shear rate is lower in the superficial femoral compared with the brachial artery in the supine, seated, and standing postures. These findings of lower shear rates in the superficial femoral artery may be one mechanism for the higher propensity for atherosclerosis in the arteries of the leg than of the arm.


Assuntos
Artéria Braquial/fisiologia , Artéria Femoral/fisiologia , Postura , Adulto , Velocidade do Fluxo Sanguíneo , Pressão Sanguínea , Artéria Braquial/diagnóstico por imagem , Feminino , Artéria Femoral/diagnóstico por imagem , Frequência Cardíaca , Hemorreologia , Humanos , Fluxometria por Laser-Doppler , Masculino , Valores de Referência , Fluxo Sanguíneo Regional , Ultrassonografia
3.
Arch Virol ; 149(11): 2171-86, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15503205

RESUMO

Borna disease virus (BDV) infection in its predominant natural host - horses and sheep - leads to fatal meningoencephalomyelitis. The immune-mediated disease can also be induced experimentally in rats following intra- cerebral BDV infection. Despite a vigorous immune response, BDV persists in the central nervous system (CNS) in surviving rats. However, immunization of rats with BDV-specific T-cells prior to challenge with BDV prevents neurological disease and results in virus clearance from the CNS. To analyze whether interferon gamma (IFNgamma) might contribute to viral clearance in the rat brain, we tested the susceptibility of BDV to the antiviral action of rat IFNgamma using different rat cell lines. Even at high concentrations of IFNgamma, BDV infection of astrocyte and fibroblast cell lines as well as of rat embryo cells could not be inhibited efficiently. Similarly, infection of cultured rat hippocampal slices with BDV was not inhibited by rat IFNgamma. In contrast, de novo BDV infection of monkey kidney cells as well as human oligodendroglial cells was blocked by preincubation with human IFNgamma. Furthermore, IFNgamma reduced the BDV load in persistently BDV-infected human oligodendroglial cells but not in infected rat astrocytes. These data suggest species-specific differences in the susceptibility of BDV to the antiviral action of IFNgamma.


Assuntos
Antivirais/farmacologia , Vírus da Doença de Borna/efeitos dos fármacos , Interferon gama/farmacologia , Animais , Doença de Borna/prevenção & controle , Linhagem Celular , Feminino , Hipocampo/virologia , Humanos , Ratos , Ratos Endogâmicos Lew , Especificidade da Espécie , Replicação Viral/efeitos dos fármacos
4.
Arch Virol ; 148(1): 45-63, 2003 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-12536295

RESUMO

Infection of newborn rats with Borna disease virus (BDV) leads to viral persistence in the central nervous system without overt signs of inflammation. Nevertheless, these rats display distinct behavioral and neurodevelopmental abnormalities. The molecular basis of the latter is still unknown. Using a cDNA array representing 1200 genes, we sought to identify cellular genes which are differentially expressed following perinatal BDV-infection. RNA samples prepared from different brain regions were analysed at various time points before or after BDV-induced defects become evident. In infected brains, we found upregulated expression of genes encoding brain fatty acid binding protein (B-FABP), beta2-microglobulin (beta2m) and, as described previously, the chemokine IP-10. Kinetic studies revealed sustained increased expression of B-FABP in infected frontal cortices beginning about three weeks p.i. Moreover, a slight transient increase of B-FABP expression in infected hippocampi was observed 3-5 weeks p.i. In situ hybridization studies combined with immunohistochemistry suggested that expression of beta2m was predominantly upregulated in glial cells and possibly also in some neurons. Employing cultured infected hippocampus slices and infected genetically modified mice, we provide evidence, that the observed upregulation of beta2m expression is not triggered by IFN-gamma, but rather by IFN-alpha/beta.


Assuntos
Doença de Borna/genética , Vírus da Doença de Borna/genética , Encéfalo/virologia , Expressão Gênica , Animais , Animais Recém-Nascidos , Doença de Borna/patologia , Encéfalo/imunologia , Quimiocina CXCL10 , Quimiocinas/metabolismo , Quimiocinas CXC/metabolismo , Ácidos Graxos/metabolismo , Hipocampo/citologia , Hipocampo/virologia , Inflamação , Cinética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Técnicas de Cultura de Órgãos , Ligação Proteica , Ratos , Ratos Endogâmicos Lew , Regulação para Cima , Microglobulina beta-2/metabolismo
6.
J Neurovirol ; 7(6): 501-10, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11704882

RESUMO

In the course of retroviral CNS infections, microglia activation has been observed frequently, and it has been hypothesized that activated microglia produce and secrete neurotoxic products like proinflammatory cytokines, by this promoting brain damage. We challenged this hypothesis in a rat model for neurodegeneration. In a kinetic study, we found that microglia cells of rats neonatally inoculated with neurovirulent murine leukemia virus (MuLV) NT40 became infected in vivo to maximal levels within 9-13 days postinoculation (d.p.i.). Beginning from 13 d.p.i., degenerative alterations, i.e., vacuolization of neurons and neuropil were found in cerebellar and other brain-stem nuclei. Elevated numbers of activated microglia cells--as revealed by immunohistochemical staining with monoclonal antibody ED1--were first detected at 19 d.p.i. and were always locally associated with degenerated areas but not with nonaltered, yet infected, brain regions. Both neuropathological changes and activated microglia cells increased in intensity and numbers, respectively, with ongoing infection but did not spread to other than initially affected brain regions. By ribonuclease protection assays, we were unable to detect differences in the expression levels of tumor-necrosis-factor-alpha (TNF-alpha), interleukin-1beta (IL-1beta), and interleukin-6 (IL-6) in microglia cells nor in total brains from infected versus uninfected rats. Our results suggest that the activation of microglia in the course of MuLV neurodegeneration is rather a reaction to, and not the cause of, neuronal damage. Furthermore, overt expression of the proinflammatory cytokines TNF-alpha, IL-1beta, and IL-6 within the CNS is not required for the induction of retroviral associated neurodegeneration in rats.


Assuntos
Vírus da Leucemia Murina , Microglia/imunologia , Doenças Neurodegenerativas/imunologia , Doenças Neurodegenerativas/virologia , Infecções por Retroviridae/imunologia , Animais , Córtex Cerebral/imunologia , Encefalite Viral/imunologia , Encefalite Viral/patologia , Encefalite Viral/virologia , Expressão Gênica/imunologia , Imuno-Histoquímica , Interleucina-1/genética , Interleucina-1/imunologia , Interleucina-6/genética , Interleucina-6/imunologia , Microglia/virologia , Doenças Neurodegenerativas/patologia , RNA Mensageiro/análise , Ratos , Ratos Endogâmicos F344 , Infecções por Retroviridae/patologia , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/imunologia , Proteínas do Envelope Viral/análise , Proteínas do Envelope Viral/imunologia
7.
Behav Brain Res ; 120(2): 189-201, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11182167

RESUMO

Borna disease virus (BDV) is a highly neurotropic RNA virus that causes a CD8(+) T cell-mediated neurological disease in certain mouse strains. We established asymptomatic persistent central nervous system (CNS) infections in mutant C57BL/10J mice that lack functional CD8(+) T cells. When analyzed at adult age for spatial learning abilities in a water maze, BDV-infected mice showed slightly impaired escape performance while their exploratory behavior in an openfield test was indistinguishable from uninfected control mice. Histological and molecular biological analysis revealed extensive viral spread throughout the CNS of infected animals. Most neurons of the hippocampus contained viral antigen, but there was no overt loss of neurons from this structure. We found almost unchanged levels of the proinflammatory cytokines IL-1beta and TNF-alpha, but clearly increased levels of the chemokines IP-10 and RANTES in brains of infected mice. Re-examination of water maze data revealed that only infected mice with IP-10 transcript levels above a certain threshold showed impaired performance, whereas the performance of infected mice with lower IP-10 levels was indistinguishable from uninfected controls. This suggests that BDV infection can disturb the function of the mammalian CNS without causing overt neuronal loss, and that the magnitude of virus-induced chemokine production in the CNS correlates with the degree of impairment.


Assuntos
Doença de Borna/metabolismo , Doença de Borna/psicologia , Vírus da Doença de Borna , Infecções do Sistema Nervoso Central/metabolismo , Infecções do Sistema Nervoso Central/psicologia , Quimiocinas/biossíntese , Deficiências da Aprendizagem/psicologia , Animais , Antineoplásicos/metabolismo , Comportamento Animal/fisiologia , Biomarcadores , Northern Blotting , Doença de Borna/complicações , Quimiocina CXCL10/biossíntese , Comportamento Exploratório/fisiologia , Imuno-Histoquímica , Deficiências da Aprendizagem/etiologia , Aprendizagem em Labirinto/fisiologia , Memória/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , RNA/biossíntese , Ribonucleases/metabolismo , Carga Viral
8.
Int J Oncol ; 18(2): 281-6, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11172593

RESUMO

Human SV40-transformed cells contain high levels of stabilized p53 of which only a fraction is complexed with the SV40 large tumor antigen (T-antigen). This raises the question whether the p53 which is not complexed with T-antigen retains some biological activity. Two human SV40-transformed cell lines, BEAS and SV80, were investigated. A significant level of constitutive cognate-sequence-specific DNA-binding of p53 was detected by electrophoretic mobility shift assay (EMSA) of cell extracts. Upon DNA damage by treatment with mitomycin C the DNA-binding activity was increased, as known for cells with wild-type p53. However, in both cell lines, before and after DNA damage, p53 was not able to transactivate a target gene as shown by reporter gene assay. Hence, the capability of p53 to bind its cognate sequence is a prerequisite but no proof of p53 transactivating activity. Nuclear p53 levels were not further increased after mitomycin C treatment, occasionally rather slightly decreased, often accompanied by an even larger decrease in amount of T-antigen. In conclusion, SV40-transformation of human cells has caused a loss of essential features of wild-type p53 activity, even in that fraction of p53 not in physical complex with SV40 T-antigen.


Assuntos
Antígenos Transformantes de Poliomavirus/metabolismo , Dano ao DNA/fisiologia , Proteína Supressora de Tumor p53/metabolismo , Animais , Linhagem Celular/efeitos dos fármacos , Linhagem Celular/metabolismo , Linhagem Celular Transformada , Reagentes de Ligações Cruzadas/farmacologia , Dano ao DNA/efeitos dos fármacos , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Mitomicina/farmacologia , Vírus 40 dos Símios/metabolismo
9.
Science ; 290(5495): 1331-4, 2000 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-11082056

RESUMO

A simple method was used to assemble single-walled carbon nanotubes into indefinitely long ribbons and fibers. The processing consists of dispersing the nanotubes in surfactant solutions, recondensing the nanotubes in the flow of a polymer solution to form a nanotube mesh, and then collating this mesh to a nanotube fiber. Flow-induced alignment may lead to a preferential orientation of the nanotubes in the mesh that has the form of a ribbon. Unlike classical carbon fibers, the nanotube fibers can be strongly bent without breaking. Their obtained elastic modulus is 10 times higher than the modulus of high-quality bucky paper.

10.
J Virol ; 74(19): 9267-80, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10982374

RESUMO

Borna disease virus (BDV) causes CD8(+) T-cell-mediated meningoencephalitis in immunocompetent mice and rats, thus providing a valuable animal model for studying the mechanisms of virus-induced central nervous system (CNS) immunopathology. Chemokine-mediated leukocyte recruitment to the CNS is a crucial step in the development of neurological disease. We found increased mRNA levels of IP-10 and other chemokines in brains of adult rats following infection with BDV. The marked increase in chemokine gene expression at about day 8 postinfection seemed to immediately precede the inflammatory process. In brains of rats infected as newborns, in which inflammation was only mild and transient, sustained expression of IP-10 and RANTES genes was observed. In situ hybridization studies revealed that astrocytes were the major source of IP-10 mRNAs in brains of rats infected as newborns and as adults. In brains of infected mice lacking CD8(+) T cells (beta2m(0/0)), transcripts encoding IP-10 and RANTES were also observed. IP-10 transcripts were also present in a small number of scattered astrocytes of infected knockout mice lacking mature B and T cells as well as functional alpha/beta and gamma interferon receptors, indicating that BDV can induce chemokine synthesis in the absence of interferons and other B- or T-cell-derived cytokines. These data provide strong evidence that CNS-resident cells are involved in the early localized host immune response to infection with BDV and support the concept that chemokines are pivotal for the initiation of virus-induced CNS inflammation.


Assuntos
Astrócitos/imunologia , Astrócitos/virologia , Doença de Borna/genética , Doença de Borna/imunologia , Vírus da Doença de Borna , Quimiocinas/genética , Animais , Quimiocinas/biossíntese , Regulação Viral da Expressão Gênica , Inflamação , Masculino , Camundongos , Ratos , Ratos Endogâmicos Lew
11.
J Virol ; 74(17): 7878-83, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10933695

RESUMO

The RNA genome of Borna disease virus (BDV) shows extraordinary stability in persistently infected cell cultures. We performed bottleneck experiments in which virus populations from single infected cells were allowed to spread through cultures of uninfected cells and in which RNase protection assays were used to identify virus variants with mutations in a 535-nucleotide fragment of the M-G open reading frames. In one of the cell cultures, the major virus species (designated 2/1) was a variant with two point mutations in the G open reading frame. When fresh cells were infected with a low dose of a virus stock prepared from 2/1-containing cells, only a minority of the resulting persistently infected cultures contained detectable levels of the variant, whereas the others all seemed to contain wild-type virus. The BDV variant 2/1 remained stable in the various persistently infected cell cultures, indicating that the cells were resistant to superinfection by wild-type virus. Indeed, cells persistently infected with prototype BDV He/80 were also found to resist superinfection with strain V and vice versa. Our screen for mutations in the viral M and G genes of different rat-derived BDV virus stocks revealed that only one of four stocks believed to contain He/80 harbored virus with the original sequence. Two stocks mainly contained a novel virus variant with about 3% sequence divergence, whereas the fourth stock contained a mixture of both viruses. When the mixture was inoculated into the brains of newborn mice, the novel variant was preferentially amplified. These results provide evidence that the BDV genome is mutating more frequently than estimated from its invariant appearance in persistently infected cell cultures and that resistance to superinfection might strongly select against novel variants.


Assuntos
Vírus da Doença de Borna/genética , Genoma Viral , Animais , Astrócitos/virologia , Vírus da Doença de Borna/patogenicidade , Células Cultivadas , Variação Genética , Camundongos , Camundongos Endogâmicos , Dados de Sequência Molecular , Mutação , Ratos , Ratos Endogâmicos Lew , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sequência de DNA
12.
J Infect Dis ; 181(5): 1861-2, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10823803
13.
J Immunol Methods ; 234(1-2): 149-51, 2000 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-10669779

RESUMO

The use of multiprobe RPAs is becoming an increasingly popular method for the detection and quantitation of RNA levels in cells and tissues. Here we report that due to a polymorphism in the 3'-noncoding region of the mouse Crg-2/IP-10 gene, the mCK-5 chemokine probe set available from Pharmingen can yield aberrant signal patterns with RNA samples from BALB/c, MRL and possibly other mouse strains that may lead to false conclusions regarding expression of the Crg-2/IP-10 and MCP-1 genes.


Assuntos
Quimiocinas CXC/genética , Monocinas/genética , Polimorfismo Genético , Animais , Sequência de Bases , Quimiocina CXCL10 , DNA Complementar , Perfilação da Expressão Gênica , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos MRL lpr , Dados de Sequência Molecular , Kit de Reagentes para Diagnóstico , Ribonucleases
14.
J Neurovirol ; 6(6): 462-77, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11175319

RESUMO

Infection of newborn rats with Borna disease virus (BDV) leads to persistence in the absence of overt signs of inflammation. BDV persistence, however, causes cerebellar hypoplasia and hippocampal dentate gyrus neuronal cell loss, which are accompanied by diverse neurobehavioral abnormalities. Neurotrophins and their receptors play important roles in the differentiation and survival of hippocampal and cerebellar neurons. We have examined whether BDV can cause alterations in the neurotrophin network, thus promoting neuronal damage. We have used RNase protection assay to measure mRNA levels of the neurotrophins nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF), and neurotrophin-3 (NT-3), and their trkC and trkB receptors, as well as the growth factors insulin-like growth factor I (IGF-1) and basic fibroblast growth factor (bFGF), in the cerebellum and hippocampus of BDV-infected and control rats at different time points p.i. Reduced mRNA expression levels of NT-3, BDNF and NGF were found after day 14 p.i. in the hippocampus, but not in the cerebellum, of newborn infected rats. Three weeks after infection, trkC mRNA expression levels were reduced in both hippocampus and cerebellum of infected rats, whereas decreased trkB mRNA levels were only observed in the cerebellum. Reduced trkC mRNA expression was confined to the dentate gyrus of the hippocampus, as assessed by in situ hybridization. TUNEL assay revealed massive apoptotic cell death in the dentate gyrus of infected rats at days 27 and 33 p.i. Increased numbers of apoptotic cells were also detected in the cerebellar granular layer of infected rats after 8 days p.i. Moreover, a dramatic loss of cerebellar Purkinje cells was seen after day 27 p.i. Our results support the hypothesis, that BDV-induced alterations in neurotrophin systems might contribute to selective neuronal cell death.


Assuntos
Doença de Borna/genética , Vírus da Doença de Borna/patogenicidade , Encéfalo/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Fatores de Crescimento Neural/biossíntese , Proteínas do Tecido Nervoso/biossíntese , Receptores de Fator de Crescimento Neural/biossíntese , Animais , Animais Recém-Nascidos , Apoptose , Doença de Borna/metabolismo , Encéfalo/virologia , Fator Neurotrófico Derivado do Encéfalo/biossíntese , Fator Neurotrófico Derivado do Encéfalo/deficiência , Fator Neurotrófico Derivado do Encéfalo/genética , Cerebelo/metabolismo , Cerebelo/patologia , Feminino , Fator 2 de Crescimento de Fibroblastos/biossíntese , Fator 2 de Crescimento de Fibroblastos/genética , Hipocampo/metabolismo , Hipocampo/patologia , Hibridização In Situ , Marcação In Situ das Extremidades Cortadas , Fator de Crescimento Insulin-Like I/biossíntese , Fator de Crescimento Insulin-Like I/genética , Masculino , Modelos Neurológicos , Fator de Crescimento Neural/biossíntese , Fator de Crescimento Neural/deficiência , Fator de Crescimento Neural/genética , Fatores de Crescimento Neural/genética , Proteínas do Tecido Nervoso/genética , Neurônios/metabolismo , Neurônios/patologia , Neurotrofina 3/biossíntese , Neurotrofina 3/deficiência , Neurotrofina 3/genética , Isoformas de Proteínas/biossíntese , Isoformas de Proteínas/genética , Células de Purkinje/patologia , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Ratos , Ratos Endogâmicos Lew , Receptor trkB/biossíntese , Receptor trkB/genética , Receptor trkC/biossíntese , Receptor trkC/genética , Receptores de Fator de Crescimento Neural/genética
15.
J Infect Dis ; 180(5): 1695-9, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10515835

RESUMO

To estimate the frequency of persistent Borna disease virus (BDV) infections of the human central nervous system and to determine which neuropsychiatric disorders might be associated with this viral infection, reverse transcription-nested polymerase chain reaction was used to screen a large collection of autopsy brain samples for the presence of BDV-specific nucleic acids. The presence of BDV RNA was found in 3 brains of persons with psychiatric symptoms and prominent hippocampal degeneration previously reported to be positive by others. However, no BDV RNA was detected in 86 randomly collected brains from persons with various psychiatric disorders, including schizophrenia, affective disorders, and Alzheimer's disease, or from suicide victims or in 52 brains from healthy controls. Furthermore, no BDV-RNA was detected in 16 surgical brain samples from persons with epilepsy-associated hippocampal sclerosis. These results indicate that life-long persistent BDV infections are rare in humans and that such infections may be associated with certain forms of hippocampal degeneration.


Assuntos
Doença de Borna/complicações , Vírus da Doença de Borna/isolamento & purificação , Encéfalo/virologia , Hipocampo , Transtornos Mentais/virologia , Doenças Neurodegenerativas/virologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Doença de Borna/virologia , Vírus da Doença de Borna/genética , Epilepsia/complicações , Feminino , Hipocampo/patologia , Hipocampo/virologia , Humanos , Masculino , Transtornos Mentais/complicações , Pessoa de Meia-Idade , Doenças Neurodegenerativas/complicações , RNA Viral/análise , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Esclerose
17.
J Neuroimmunol ; 96(1): 29-45, 1999 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-10227422

RESUMO

Borna disease virus (BDV) causes central nervous system (CNS) disease in several vertebrate species, which is frequently accompanied by behavioral abnormalities. In the adult rat, intracerebral (i.c.) BDV infection leads to immunomediated meningoencephalitis. In contrast, i.c. infection of neonates causes a persistent infection in the absence of overt signs of brain inflammation. These rats (designated PTI-NB) display distinct behavioral and neurodevelopmental abnormalities. However, the molecular mechanisms for these virally induced CNS disturbances are unknown. Cytokines play an important role in CNS function, both under normal physiological and pathological conditions. Astrocytes and microglia are the primary resident cells of the central nervous system with the capacity to produce cytokines. Strong reactive astrocytosis is observed in the PTI-NB rat brain. We have used a ribonuclease protection assay to investigate the mRNA expression levels of proinflammatory cytokines in different brain regions of PTI-NB and control rats. We show here evidence of a chronic upregulation of proinflammatory cytokines interleukin-6, tumor necrosis factor alpha, interleukins-1alpha, and -1beta in the hippocampus and cerebellum of the PTI-NB rat brain. These brain regions exhibited only a very mild and transient immune infiltration. In contrast, in addition to reactive astrocytes, a strong and sustained microgliosis was observed in the PTI-NB rat brains. Our data suggest that CNS resident cells, namely astrocytes and microglia, are the major source of cytokine expression in the PTI-NB rat brain. The possible implications of these findings are discussed.


Assuntos
Doença de Borna/imunologia , Vírus da Doença de Borna , Encéfalo/imunologia , Citocinas/biossíntese , Encefalite Viral/imunologia , Animais , Animais Recém-Nascidos , Astrócitos/imunologia , Astrócitos/virologia , Encéfalo/citologia , Encéfalo/virologia , Cerebelo/citologia , Cerebelo/imunologia , Cerebelo/virologia , Córtex Cerebral/citologia , Córtex Cerebral/imunologia , Córtex Cerebral/virologia , Citocinas/imunologia , Feminino , Expressão Gênica/imunologia , Proteína Glial Fibrilar Ácida/análise , Hipocampo/citologia , Hipocampo/imunologia , Hipocampo/virologia , Interleucina-1/biossíntese , Interleucina-1/imunologia , Interleucina-6/biossíntese , Interleucina-6/imunologia , Microglia/imunologia , Microglia/virologia , Plasmídeos , Gravidez , RNA Viral/análise , Ratos , Ratos Endogâmicos Lew , Linfócitos T/imunologia , Linfócitos T/virologia , Fator de Necrose Tumoral alfa/biossíntese , Fator de Necrose Tumoral alfa/imunologia , Carga Viral
18.
J Virol Methods ; 71(2): 229-45, 1998 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9626956

RESUMO

Borna disease virus (BDV) infection of domestic animals and humans appears to have a worldwide distribution. There is evidence suggesting an association of BDV with certain psychiatric disorders. However, more comprehensive epidemiological studies are required to establish rigorously a link between BDV and human mental disorders, and to evaluate the role of carrier animals as potential source of BDV for human infection. The use of RT-PCR to detect BDV RNA in peripheral blood mononuclear cells (PBMCs) of infected individuals is a powerful tool to address these questions. The comparison of discrepant results reported by different investigators using this approach is hampered by the lack of controls to assess the sensitivity and reproducibility of the assays. Procedures are now described that allow the establishment of standardized controls to evaluate the performance of the RT-PCR assays. This RT-PCR assay detected reproducibly 100 copies of BDV p40 RNA in 5 microg of RNA. The data illustrate that the number of PBMCs used for RNA preparation, rather than the amount of RNA, has a critical influence on the outcome of the RT-PCR assay. Evidence is provided that levels of BDV in blood do not necessarily reflect viral load in brain.


Assuntos
Doença de Borna/epidemiologia , Vírus da Doença de Borna/isolamento & purificação , Reação em Cadeia da Polimerase/métodos , RNA Viral/sangue , Animais , Northern Blotting , Doença de Borna/diagnóstico , Vírus da Doença de Borna/genética , Vírus da Doença de Borna/fisiologia , Encéfalo/virologia , Humanos , Processamento de Imagem Assistida por Computador , Leucócitos Mononucleares/virologia , Linfoma , Reação em Cadeia da Polimerase/normas , Ratos , Ratos Endogâmicos Lew , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Células Tumorais Cultivadas , Carga Viral , Proteínas Virais/genética
19.
J Clin Microbiol ; 36(1): 286-9, 1998 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9431969

RESUMO

Forty-four clinical samples positive for GB virus C (GBV-C)/hepatitis G virus (HGV) were tested with six primer sets, four from the 5' untranslated region (5'-UTR) and two from the NS5a genomic region. Two of the 5'-UTR primer sets, when used in a single-round 60-cycle PCR, detected between 86.4 and 97.7% of the positive samples, while two different sets from the same area, when used in a nested PCR, amplified between 97.7 and 100% of the positive specimens. Both sets from the NS5a region, when used in a single-round PCR, detected 95.5% of the GBV-C/HGV-positive samples. Parallel testing with two PCR sets, one from the 5'-UTR and a second from NS5a, may eliminate false-negative results attributable to the genetic heterogeneity of the virus.


Assuntos
Flaviviridae/genética , Hepacivirus/genética , Reação em Cadeia da Polimerase , RNA Viral/análise , Primers do DNA , Humanos
20.
Brain Res Bull ; 44(6): 647-64, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9421127

RESUMO

Viruses with the ability to establish persistent infection in the central nervous system (CNS) can induce progressive neurologic disorders associated with diverse pathological manifestations. Clinical, epidemiological, and virological evidence supports the hypothesis that viruses contribute to human mental diseases whose etiology remains elusive. Therefore, the investigation of the mechanisms whereby viruses persist in the CNS and disturb normal brain function represents an area of research relevant to clinical and basic neurosciences. Borna disease virus (BDV) causes CNS disease in several vertebrate species characterized by behavioral abnormalities. Based on its unique features, BDV represents the prototype of a new virus family. BDV provides an important model for the investigation of the mechanisms and consequences of viral persistence in the CNS. The BDV paradigm is amenable to study virus-cell interactions in the CNS that can lead to neurodevelopmental abnormalities, immune-mediated damage, as well as alterations in cell differentiated functions that affect brain homeostasis. Moreover, seroepidemiological data and recent molecular studies indicate that BDV is associated with certain neuropsychiatric diseases. The potential role of BDV and of other yet to be uncovered BDV-related viruses in human mental health provides additional impetus for the investigation of this novel neurotropic infectious agent.


Assuntos
Vírus da Doença de Borna , Encéfalo/virologia , Animais , Doença de Borna/patologia , Doença de Borna/virologia , Encéfalo/patologia , Humanos
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