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1.
Leukemia ; 10(3): 552-7, 1996 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8642874

RESUMO

Epidemiological studies of HTLV-I infection have demonstrated the presence of this virus in certain Amerindian populations in Central and South America. We have recently reported the first evidence of endemic HTLV-I infection in North American Amerindians from the coastal regions of British Columbia, Canada. While the predominant HTLV-I-associated disease observed in British Columbia Amerindians is the HTLV-I associated neurological disease (HTLV-I-associated myelopathy/tropical spastic paraparesis), we report here the first two cases of HTLV-I-associated adult T cell leukemia/lymphoma (ATL). Clinical and PCR evidence to support the diagnosis of HTLV-I-associated ATL in these two Amerindians is presented. Both cases of ATL were found in the same tribe although neither patient was directly related to each other. While reports of HTLV-I-associated ATL have been reported in Circumartic native peoples, reports of ATL in North American single ancestry Amerindians have not been previously made to our knowledge.


Assuntos
Indígenas Norte-Americanos , Leucemia-Linfoma de Células T do Adulto/etnologia , Adulto , Southern Blotting , Colúmbia Britânica , DNA Viral/análise , Feminino , Vírus Linfotrópico T Tipo 1 Humano/genética , Vírus Linfotrópico T Tipo 1 Humano/isolamento & purificação , Humanos , Imunofenotipagem , Leucemia-Linfoma de Células T do Adulto/diagnóstico , Leucemia-Linfoma de Células T do Adulto/virologia , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase
2.
Arch Neurol ; 51(11): 1120-4, 1994 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-7980107

RESUMO

OBJECTIVE: To conduct a prospective assessment of pregnancy on women with multiple sclerosis (MS), focusing on pregnancy outcome and relapses during gestation and up to 6 months after delivery. DESIGN: Expected numbers of relapses were based on data for (1) "self-controls": the mothers ("cases") themselves prior to becoming pregnant and (2) "matched controls": female patients with MS "matched" to the mothers for year of birth, age of MS onset, MS type, MS course, and initial MS symptom(s). SETTING: Cases and controls were identified from an ambulatory care MS clinic that serves the province of British Columbia, Canada. PATIENTS OR OTHER PARTICIPANTS: Women with a diagnosis of MS who attended the MS clinic during 1982 through 1986 and subsequently became pregnant during 1982 through 1989 inclusive were included in this study as cases. Matched controls were women with MS who attended the MS clinic during the same period but did not become pregnant. RESULTS: No significant increase in relapse rate was found for cases during the first two trimesters of gestation. The number of relapses was significantly less than expected during the third trimester compared with matched controls (chi 2 = 6.80, df = 1, P < .02), but not compared with self-controls (chi 2 = 3.39, df = 1, P > .05). The observed number of relapses for the 6 months after delivery did not differ significantly from expected (self-controls: chi 2 = 2.84, df = 2, P > .05; matched controls: chi 2 = 1.76, df = 2, P > .05). CONCLUSION: These data suggest that neither pregnancy nor the 6-month period after delivery is a risk factor for relapse in MS. They are consistent with previous observations that, in the long term, pregnancy does not influence subsequent MS disability.


Assuntos
Esclerose Múltipla/etiologia , Resultado da Gravidez , Feminino , Humanos , Esclerose Múltipla/complicações , Gravidez , Recidiva
3.
Mech Ageing Dev ; 23(1): 11-9, 1983 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-6228697

RESUMO

Age-related changes in the processes involved in T cell dependent polyclonal B cell activation in man were studied by comparing immunoglobulin (Ig) produced in autologous T:B (E+:E-) cell cultures of young and old donor pairs with Ig produced in crossover cultures. Each young and old donor was classified as a responder or a non-responder based on Ig levels in autologous pokeweed mitogen-activated T:B cultures. The data indicate that: (1) T suppressor influences are a major determinant of non-response in the young; (2) T cells of nonresponder old donors can support high levels of Ig secretion by young donors' B cells; (3) low response to pokeweed mitogen stimulation in the elderly may reflect either direct refractoriness of B cells to T cell dependent stimulation, heightened B cell sensitivity to suppressor signals, or a combination of the two.


Assuntos
Envelhecimento , Imunoglobulinas/metabolismo , Adulto , Idoso , Linfócitos B/imunologia , Células Cultivadas , Humanos , Cooperação Linfocítica , Mitógenos de Phytolacca americana , Linfócitos T/imunologia , Linfócitos T Reguladores/imunologia
4.
Neurology ; 42(3 Pt 1): 586-9, 1992 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-1296581

RESUMO

We have reviewed thymus histology, preoperative serum acetylcholine receptor antibody status, and clinical features of all 50 patients who underwent thymectomy for generalized myasthenia gravis in the University of British Columbia-affiliated hospitals over the last 8 years. Seven patients had thymoma, 25 had hyperplasia, and 18 had a normal thymus. The seven thymoma patients all had severe limb involvement and all had circulating antibodies against the acetylcholine receptor. Patients without circulating antibodies had only minimal limb involvement and half of them had a normal thymus. Only two of the 32 (6%) patients with abnormal thymus were antibody-negative; this contrasts with six of the 18 patients (33%) with normal thymus. We conclude that seronegative patients with generalized myasthenia gravis constitute a distinct subgroup which may not be immunologically homogeneous and could be subgrouped with normal or abnormal thymic histology.


Assuntos
Anticorpos/análise , Miastenia Gravis/patologia , Adolescente , Adulto , Idoso , Feminino , Humanos , Imunoterapia , Masculino , Pessoa de Meia-Idade , Miastenia Gravis/imunologia , Miastenia Gravis/terapia , Receptores Colinérgicos/imunologia , Timectomia , Timo/patologia
5.
Neurology ; 39(7): 959-63, 1989 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-2739924

RESUMO

Increased blood-brain barrier (BBB) permeability, important in the pathogenesis of MS, may be demonstrated as lesion enhancement with high-volume delayed CT (HVDCT). We studied 40 MS patients with history, neurologic examination, HVDCT, and MRI. In addition, 7 of the patients with enhancing CT lesions were followed with serial MRI for up to 3 years and 7 months. In 3 of these patients we repeated the HVDCT. Patients with enhancing lesions on CT were younger, had shorter duration of disease, and had more frequent clinical relapses than did patients without enhancement. More than half (56%) of the enhancing CT lesions were in the deep white matter, 23% were periventricular, and 21% were at the gray/white matter junction. Half the CT enhancing lesions, when followed by serial MRI, showed significant changes in lesion size. Although the majority (59%) of these lesions faded, some remained actively changing (25%) or became confluent with adjacent lesions (16%). In 48% of the MRI examinations that showed activity, some lesions were increasing in size while others were simultaneously decreasing in size. This study confirms that MS is a dynamic process in which recurrent episodes of BBB disruption and inflammation play a major role. Recurrent episodes of inflammation may well be a prelude to the largely irreversible changes of demyelination and gliosis.


Assuntos
Esclerose Múltipla/diagnóstico , Doença Aguda , Adulto , Idoso , Idoso de 80 Anos ou mais , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Doença Crônica , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos
6.
Neurology ; 34(9): 1155-60, 1984 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-6235461

RESUMO

The proportion of MS patients whose pokeweed mitogen-stimulated mononuclear cells (MNCs) secreted greater than 1,000 ng/ml IgG per 10(6) cells (ie, "high responders") was increased compared with controls. The suppressor effect mediated by a constant number of T8+ cells from high responders, both MS and control, on IgG secretion by standard T helper (T4+) plus B-cell cultures was significantly lower than that for the same number of T8+ cells from "low responders." The proportion of T8+ cells within MNCs from MS patients did not correlate with levels of IgG secretion. Our results indicate that high levels of IgG secretion by MNCs, an occurrence overrepresented in the MS population, is significantly influenced by functional properties of T suppressor cells.


Assuntos
Imunoglobulina G/imunologia , Esclerose Múltipla/imunologia , Linfócitos T Reguladores/imunologia , Adolescente , Adulto , Feminino , Humanos , Contagem de Leucócitos , Linfócitos/imunologia , Masculino , Pessoa de Meia-Idade
7.
Neurology ; 41(12): 1936-41, 1991 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-1745353

RESUMO

Immunologic functions are studied in conjunction with a placebo-controlled trial of lymphoblastoid interferon (IFN) in patients with chronic progressive (CP) multiple sclerosis. Prior to treatment, CD4+ cells are significantly increased and CD8+ cells decreased in the blood of MS patients. Both CD5+ and CD4+ cells increase significantly with IFN therapy early during the treatment phase of the trial, while the number of CD8+ cells decreases steadily, becoming significant at 6 months. CNS IgG synthesis rates increase with IFN treatment and maximize at 3 months. Serum antiviral activity also increases with IFN treatment. In the IFN-treated group, a trend toward improvement, determined clinically and by MRI, likely reflects the influence of a subpopulation of 10 patients. This subpopulation is now further characterized by an early increase in CNS IgG synthesis and numbers of CD5+ cells in the blood. Although these immune functions may identify a number of CP MS patients who might benefit from IFN, it is unlikely that these mechanisms actually mediate the potentially beneficial effects of this cytokine.


Assuntos
Interferon-alfa/uso terapêutico , Esclerose Múltipla/tratamento farmacológico , Esclerose Múltipla/imunologia , Adulto , Análise de Variância , Método Duplo-Cego , Feminino , Humanos , Sistema Imunitário/efeitos dos fármacos , Imunoglobulina G/biossíntese , Interferon-alfa/sangue , Linfócitos/efeitos dos fármacos , Masculino , Pessoa de Meia-Idade
8.
Neurology ; 41(5): 657-60, 1991 May.
Artigo em Inglês | MEDLINE | ID: mdl-2027480

RESUMO

We previously compared the diagnostic capabilities of MRI of the head with CT, evoked potentials, and CSF oligoclonal banding (OB) analysis in a prospective evaluation of 200 patients with suspected multiple sclerosis (MS). To examine the ability of MRI and other paraclinical tests to predict the diagnosis of clinically definite MS (CDMS), we did a systematic clinical follow-up of 200 patients who were previously reported. In that study, 85 of 200 could be diagnosed as having laboratory-supported definite MS (LSDMS). In follow-up, we excluded one patient diagnosed as LSDMS who in retrospect was considered to have had CDMS at entry and 15 patients who were eventually diagnosed as having other diseases. After a mean follow-up of 2.1 years, 55 of the remaining 184 patients (30%) had developed CDMS. Thirty-eight of 84 patients with an original diagnosis of LSDMS (45%) and 17 of the remaining 100 patients with suspected MS (17%) had become CDMS. Forty-six of the 55 patients who developed CDMS in follow-up (84%) had an initial MRI that was strongly suggestive of MS. Fifty-two of those 55 CDMS patients (95%) had at least one MS-like abnormality on MRI when originally studied. In contrast, 38 of 55 (69%) had CSF OB, 38 of 55 (69%) had an abnormal VEP, 35 of 55 (64%) had an abnormal SEP, and 21 of 55 (38%) had an abnormal CT when first studied. MRI was the most sensitive single paraclinical test for predicting CDMS. CDMS developed during follow-up in 46 of the 94 patients (49%) whose initial MRI was strongly suggestive of MS.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Encéfalo/patologia , Esclerose Múltipla/diagnóstico , Adolescente , Adulto , Encéfalo/diagnóstico por imagem , Potenciais Evocados , Feminino , Seguimentos , Humanos , Imageamento por Ressonância Magnética , Masculino , Esclerose Múltipla/diagnóstico por imagem , Esclerose Múltipla/fisiopatologia , Prognóstico , Tomografia Computadorizada por Raios X
9.
Neurology ; 40(3 Pt 1): 479-86, 1990 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-2179764

RESUMO

A randomized, double-blind, placebo-controlled, noncrossover trial determined the efficacy of lymphoblastoid interferon (IFN) in chronic progressive multiple sclerosis (CP MS). Fifty patients received 5 X 10(6) IU IFN subcutaneously daily for 6 months while 50 received placebo. After 2 years, there were no significant differences between the 2 groups based on clinical evaluations and quantitative MRI analysis of the brain, although a trend was observed in the IFN group. Clinically, the IFN group was worse at 1 and 3 months and improved at 6 to 18 months, when compared with the placebo group. Results of MRI evaluations of the brain at 6 months support this trend. This trend likely resulted from a subpopulation of 10 IFN-treated patients, characterized by a higher women:men ratio and a lower EDSS score at entry into the trial. We cannot recommend lymphoblastoid IFN as treatment for CP MS at this time.


Assuntos
Interferon Tipo I/uso terapêutico , Esclerose Múltipla/terapia , Adulto , Encéfalo/patologia , Método Duplo-Cego , Estudos de Avaliação como Assunto , Feminino , Humanos , Interferon Tipo I/efeitos adversos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla/patologia , Esclerose Múltipla/fisiopatologia , Ensaios Clínicos Controlados Aleatórios como Assunto , Estatística como Assunto
10.
Neurology ; 38(2): 180-5, 1988 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-3340277

RESUMO

We compared the diagnostic capabilities of MRI to CT, evoked potentials (EP), and CSF oligoclonal banding analysis in a prospective evaluation of 200 patients with suspected multiple sclerosis (MS). MRI was the best method for demonstrating dissemination in space. An abnormal appropriate EP in monosymptomatic disease was usually supported by MRI and CSF analysis as being predictive of MS as a clinical diagnosis. A normal appropriate EP study was not satisfactory because MRI and CSF analysis often did not support a diagnosis of non-MS. When there is agreement between three of these paraclinical studies, the diagnosis of MS is probably unequivocal. For use in research studies, laboratory-supported definite MS (LSDMS) could be diagnosed in 85 patients of the total 200 (42.5%), in 19/38 (50%) of optic neuritis (ON) patients, and in 24/52 (46%) of chronic progressive myelopathy (CPM) patients. MRI was 100% successful in identifying patients who qualified for LSDMS in the ON and CPM groups. In a short follow-up (less than 1 year), 19/200 (10%) went on to develop clinically definite MS (CDMS), and MRI predicted that diagnosis in 18/19 (95%). Only long-term follow-up will show how well these studies and the category of LSDMS predict the development of CDMS. The clinical diagnosis of MS (CDMS), even though only 95% accurate, must remain the gold standard.


Assuntos
Imageamento por Ressonância Magnética , Esclerose Múltipla/diagnóstico , Adolescente , Adulto , Idoso , Criança , Potenciais Somatossensoriais Evocados , Potenciais Evocados Visuais , Feminino , Humanos , Imunoglobulinas/líquido cefalorraquidiano , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla/líquido cefalorraquidiano , Esclerose Múltipla/diagnóstico por imagem , Estudos Prospectivos , Tomografia Computadorizada por Raios X
11.
J Immunol Methods ; 35(3-4): 189-99, 1980.
Artigo em Inglês | MEDLINE | ID: mdl-6995529

RESUMO

We describe a simple solid-phase radioimmunoassay (RIA) to detect IgG based on competitive binding between radiolabeled and unlabeled IgG for anti-IgG antibody physically adsorbed to the wells of polyvinyl microtiter plates. The assay is sensitive (1 ng), rapid, and is particularly suited for studies of in vitro IgG secretion by human peripheral blood lymphocytes, since such studies require large numbers of cultures. Conditions which permit measurement, by means of this assay, of helper and suppressor T cell effects on IgG production by human B cells in culture are described.


Assuntos
Imunoglobulina G , Linfócitos/metabolismo , Animais , Anticorpos Anti-Idiotípicos , Ligação Competitiva , Células Cultivadas , Humanos , Técnicas de Imunoadsorção , Fagócitos/metabolismo , Coelhos , Radioimunoensaio/métodos , Formação de Roseta
12.
AIDS Res Hum Retroviruses ; 16(9): 883-92, 2000 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-10875614

RESUMO

It has been established that the human T cell lymphotropic viruses type I and II (HTLV-I and HTLV-II) are both present in some indigenous peoples of the Americas. While HTLV-I has been identified in coastal British Columbia Indians (BCIs), HTLV-II has not been previously reported in the BCIs or other Canadian Amerindians. The prevalence of HTLV-I and HTLV-II in these populations has not been extensively studied. In this article, we examine a group of BCIs from Vancouver Island who belong to the Nuu-Chah-Nulth and are known to have an increased incidence of rheumatic disease. In 494 serum samples from this tribe, the levels of prevalence of HTLV-I and HTLV-II were 2.8 and 1.6%, respectively. No association could be made between arthropathy and HTLV-I infection. In addition, we characterized an HTLV-II isolate of a BCI from the coastal mainland of British Columbia and with a history of intravenous drug abuse. This case represents the first molecular characterization of a Canadian Amerindian HTLV-II isolate: a subtype IIa virus with phylogenetic affinity for intravenous drug user isolates and containing an extended form of the Tax protein. These results are consistent either with this strain having been sampled from a polymorphic ancestral pool of HTLV-II that gave rise to the current epidemic spread of this virus by intravenous drug use and sexual transmission, or with its being "back-transmitted" into the BC Amerindian population in association with intravenous drug use.


Assuntos
Vírus Linfotrópico T Tipo 1 Humano/isolamento & purificação , Vírus Linfotrópico T Tipo 2 Humano/genética , Vírus Linfotrópico T Tipo 2 Humano/isolamento & purificação , Sequência de Bases , Colúmbia Britânica/epidemiologia , DNA Viral/genética , Evolução Molecular , Genes pX , Infecções por HTLV-I/epidemiologia , Infecções por HTLV-I/virologia , Infecções por HTLV-II/epidemiologia , Infecções por HTLV-II/virologia , Vírus Linfotrópico T Tipo 2 Humano/classificação , Humanos , Indígenas Norte-Americanos , Masculino , Pessoa de Meia-Idade , Modelos Genéticos , Dados de Sequência Molecular , Filogenia , Homologia de Sequência do Ácido Nucleico , Estudos Soroepidemiológicos , Sequências Repetidas Terminais
13.
J Clin Virol ; 14(1): 37-50, 1999 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10548129

RESUMO

Several studies have reported an association between HTLV-II and a neurological condition which has come to be called HTLV-II-associated myelopathy and is similar, in some cases, to HTLV-I-associated myelopathy. To further explore the establishment of an etiological link between this virus and neurological disease, we determined the HTLV status of three individuals, one of which presented with symptoms of progressive ataxia. Since the patient with neurological disease and her husband were HTLV-II positive, we had the potential to study one of few cases of an HTLV-II-associated neurological disorder, and the first case in Canada. However, although the individual with the neurological disease was HTLV-II positive, we discovered that her brother, who displays the same clinical symptoms, was not positive for either HTLV-II or HTLV-I. Thus, disease association with HTLV-II became unsupportable. We present here, nevertheless, the first sequence and phylogenetic analysis of an HTLV-II isolate in Canada. This study suggests that cases of HTLV-II and neurological disease must be carefully investigated before any etiological conclusions can be made.


Assuntos
Ataxia/virologia , Infecções por HTLV-II/virologia , Vírus Linfotrópico T Tipo 2 Humano/isolamento & purificação , Doenças da Medula Espinal/virologia , Ataxia/sangue , Ataxia/líquido cefalorraquidiano , Sequência de Bases , DNA/análise , Feminino , Infecções por HTLV-II/sangue , Infecções por HTLV-II/líquido cefalorraquidiano , Vírus Linfotrópico T Tipo 2 Humano/genética , Humanos , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Filogenia , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Testes Sorológicos , Doenças da Medula Espinal/sangue , Doenças da Medula Espinal/líquido cefalorraquidiano , Sequências Repetidas Terminais/genética
14.
J Neurol Sci ; 53(3): 519-29, 1982 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-6978384

RESUMO

261 multiple sclerosis (MS) patients were HLA-A and -B typed and 94 were HLA-D typed. The results were compared to those of controls typed for HLA-A; HLA-B (356) and HLA-D (113). We confirm and extend earlier findings (Oger et al. 1980b) that some phenotypes could modulate the expression of the MS susceptibility gene linked to B7-DR2: DR3 was found together with DR2 in 12/94 MS and only 3/113 controls and could be marker for an "augmentor" gene. In contrast, B35 and DR1 as well as B12 and DR7 could be markers of protector genes. We compared typing results of patients subgrouped on clinical features. 61 patients with progressive evolution showed increased A1, A1-B8, B8-DR3 and A1-B8-DR3 when compared to 200 patients with remitting evolution. When compared to controls both groups showed increased B7 but only the remitting group showed increased DR2. 71 patients with "benign MS" showed increased B7-DR2 and A3-B7-DR2. 54 patients with "severe disease" showed increased DR3 and A1-B8-DR3 when compared to controls. Both groups showed increased B7 (49.2% and 44.4% versus 25.5% for controls). 120 patients treated greater than 5 years with azathioprine were divided into "no progression" and "progression" while treated. Both groups showed increased B7 when compared to controls. DR2 was increased only in the "no progression" group. B8-DR3 and A1-B8-DR3 were found increased in the "progression" group only. We conclude that two forms of MS exist with different HLA profiles.


Assuntos
Antígenos HLA/genética , Esclerose Múltipla/genética , Fenótipo , Adolescente , Adulto , Criança , Feminino , Regulação da Expressão Gênica , Ligação Genética , Antígenos HLA-B , Antígeno HLA-B7 , Antígenos HLA-DR , Antígenos de Histocompatibilidade Classe II/genética , Humanos , Masculino , Pessoa de Meia-Idade
15.
Can J Neurol Sci ; 20(4): 302-6, 1993 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8313245

RESUMO

Human T-cell lymphotropic virus type 1 (HTLV-I) is responsible for HTLV-I associated myelopathy or tropical spastic paraparesis (HAM/TSP) and for adult T-cell leukemia/lymphoma (ATLL). Both diseases have been well described in individuals living in Japan, West Indies, Seychelles Islands and Columbia where infection with HTLV-I is considered endemic and in persons whose descendants originated from these endemic areas. We report here 4 cases of HAM/TSP in 4 natives from 4 different tribal groups from British Columbia (B.C.). These are the first case reports of HTLV-I linked diseases found among North American Aboriginals. Possible routes of infection for HTLV-I infection included sexual transmission, breast feeding, blood transfusions and IV drug use. The seroprevalence of HTLV-I in North American Native population is unknown and we suggest that it is endemic in this ethnic group.


Assuntos
Indígenas Norte-Americanos , Paraparesia Espástica Tropical/epidemiologia , Adulto , Colúmbia Britânica , Feminino , Humanos , Masculino , Manitoba , Pessoa de Meia-Idade , Paraparesia Espástica Tropical/transmissão
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