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1.
Ann Rheum Dis ; 74(11): 2043-9, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25038238

RESUMO

OBJECTIVE: To evaluate genetic, demographic and clinical features in patients with cryopyrin-associated periodic syndrome (CAPS) from the Eurofever Registry, with a focus on genotype-phenotype correlations and predictive disease severity markers. METHODS: A web-based registry retrospectively collected data on patients with CAPS. Experts in the disease independently validated all cases. Patients carrying NLRP3 variants and germline-mutation-negative patients were included. RESULTS: 136 patients were analysed. The median age at disease onset was 9 months, and the median duration of follow-up was 15 years. Skin rash, musculoskeletal involvement and fever were the most prevalent features. Neurological involvement (including severe complications) was noted in 40% and 12% of the patients, respectively, with ophthalmological involvement in 71%, and neurosensory hearing loss in 42%. 133 patients carried a heterozygous, germline mutation, and 3 patients were mutation-negative (despite complete NLRP3 gene screening). Thirty-one different NLRP3 mutations were recorded; 7 accounted for 78% of the patients, whereas 24 rare variants were found in 27 cases. The latter were significantly associated with early disease onset, neurological complications (including severe complications) and severe musculoskeletal involvement. The T348M variant was associated with early disease onset, chronic course and hearing loss. Neurological involvement was less strongly associated with V198M, E311 K and A439 V alleles. Early onset was predictive of severe neurological complications and hearing loss. CONCLUSIONS: Patients carrying rare NLRP3 variants are at risk of severe CAPS; onset before the age of 6 months is associated with more severe neurological involvement and hearing loss. These findings may have an impact on treatment decisions.


Assuntos
Proteínas de Transporte/genética , Síndromes Periódicas Associadas à Criopirina/genética , Sistema de Registros , Adolescente , Adulto , Alelos , Artralgia/etiologia , Artralgia/genética , Artrite/etiologia , Artrite/genética , Criança , Pré-Escolar , Estudos de Coortes , Conjuntivite/etiologia , Conjuntivite/genética , Síndromes Periódicas Associadas à Criopirina/complicações , Síndromes Periódicas Associadas à Criopirina/fisiopatologia , Europa (Continente) , Exantema/etiologia , Exantema/genética , Feminino , Genótipo , Mutação em Linhagem Germinativa , Cefaleia/etiologia , Cefaleia/genética , Perda Auditiva Neurossensorial/etiologia , Perda Auditiva Neurossensorial/genética , Heterozigoto , Humanos , Lactente , Masculino , Meningite/etiologia , Meningite/genética , Mutação , Mialgia/etiologia , Mialgia/genética , Proteína 3 que Contém Domínio de Pirina da Família NLR , Papiledema/etiologia , Papiledema/genética , Fenótipo , Estudos Retrospectivos , Índice de Gravidade de Doença , Uveíte/etiologia , Uveíte/genética , Adulto Jovem
2.
Ann Rheum Dis ; 73(12): 2160-7, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23965844

RESUMO

OBJECTIVE: To evaluate the genetic findings, demographic features and clinical presentation of tumour necrosis factor receptor-associated autoinflammatory syndrome (TRAPS) in patients from the Eurofever/EUROTRAPS international registry. METHODS: A web-based registry collected retrospective data on patients with TNFRSF1A sequence variants and inflammatory symptoms. Participating hospitals included paediatric rheumatology centres and adult centres with a specific interest in autoinflammatory diseases. Cases were independently validated by experts in the disease. RESULTS: Complete information on 158 validated patients was available. The most common TNFRSF1A variant was R92Q (34% of cases), followed by T50M (10%). Cysteine residues were disrupted in 27% of cases, accounting for 39% of sequence variants. A family history was present in 19% of patients with R92Q and 64% of those with other variants. The median age at which symptoms began was 4.3 years but 9.1% of patients presented after 30 years of age. Attacks were recurrent in 88% and the commonest features associated with the pathogenic variants were fever (88%), limb pain (85%), abdominal pain (74%), rash (63%) and eye manifestations (45%). Disease associated with R92Q presented slightly later at a median of 5.7 years with significantly less rash or eye signs and more headaches. Children were more likely than adults to present with lymphadenopathy, periorbital oedema and abdominal pains. AA amyloidosis has developed in 16 (10%) patients at a median age of 43 years. CONCLUSIONS: In this, the largest reported case series to date, the genetic heterogeneity of TRAPS is accompanied by a variable phenotype at presentation. Patients had a median 70 symptomatic days a year, with fever, limb and abdominal pain and rash the commonest symptoms. Overall, there is little evidence of a significant effect of age or genotype on disease features at presentation.


Assuntos
Doenças Hereditárias Autoinflamatórias/genética , Receptores Tipo I de Fatores de Necrose Tumoral/genética , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Estudos de Coortes , Progressão da Doença , Exantema/etiologia , Feminino , Febre/etiologia , Genótipo , Doenças Hereditárias Autoinflamatórias/complicações , Doenças Hereditárias Autoinflamatórias/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Dor/etiologia , Fenótipo , Sistema de Registros , Estudos Retrospectivos , Fatores de Tempo , Adulto Jovem
3.
Minerva Gastroenterol Dietol ; 58(3): 201-11, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22971631

RESUMO

Adoption of laparoscopic colorectal surgery has been slow. In the United States, of approximately 250,000 colectomies each year, only 5% to 15% of these cases are being done laparoscopically. Laparoscopic colorectal surgery can be performed successfully on patients for both benign and malignant conditions in any anatomic location of the colon and rectum. The COST trial definitively established that laparoscopic colon surgery for cancer had similar rates of local recurrence and survival compared to open surgery, with better short-term outcomes. It demonstrated that laparoscopic resections resulted in shorter hospital stays, decreased IV narcotics and oral analgesics, and improved quality of life within two weeks of surgery. In the authors' clinical experience of more than 1500 laparoscopic surgeries, patients who undergo laparoscopic colorectal surgery experience decreased rates of wound infection, hernia, and bowel obstruction. One of the challenges of laparoscopic colorectal surgery is standardizing these complex, minimally invasive procedures in the operating room. With standard techniques, one can create optimal outcomes for patients, minimizing perioperative complications and maximizing oncologic results. This paper describes a sequenced step approach for each procedure to facilitate this. Left colectomy follows a nine-step process, and right colectomy follows a four-step process. Both of these procedures are described in detail. The newest horizon in minimally invasive surgery is single incision surgery, which allows for colorectal resections through a single 2.5 cm incision, producing an excellent cosmetic result. Based on this chapter, we advocate the laparoscopic approach be used as the primary method for colorectal surgery.


Assuntos
Colectomia/métodos , Neoplasias Colorretais/cirurgia , Laparoscopia , Colectomia/instrumentação , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto , Resultado do Tratamento
4.
Arthritis Rheum ; 58(6): 1823-32, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18512793

RESUMO

OBJECTIVE: To identify a set of clinical parameters that can predict the probability of carrying mutations in one of the genes associated with hereditary autoinflammatory syndromes. METHODS: A total of 228 consecutive patients with a clinical history of periodic fever were screened for mutations in the MVK, TNFRSF1A, and MEFV genes, and detailed clinical information was collected. A diagnostic score was formulated based on univariate and multivariate analyses in genetically positive and negative patients (training set). The diagnostic score was validated in an independent set of 77 patients (validation set). RESULTS: Young age at onset (odds ratio [OR] 0.94, P = 0.003), positive family history of periodic fever (OR 4.1, P = 0.039), thoracic pain (OR 4.6, P = 0.05), abdominal pain (OR 33.1, P < 0.001), diarrhea (OR 3.3, P = 0.028), and oral aphthosis (OR 0.2, P = 0.007) were found to be independently correlated with a positive genetic test result. These variables were combined in a linear score whose ability to predict a positive result on genetic testing was validated in an independent data set. In this latter set, the diagnostic score revealed high sensitivity (82%) and specificity (72%) for discriminating patients who were genetically positive from those who were negative. In patients with a high probability of having a positive result on genetic testing, a regression tree analysis provided the most reasonable order in which the genes should be screened. CONCLUSION: The proposed approach in patients with periodic fever will increase the probability of obtaining positive results on genetic testing, with good specificity and sensitivity. Our results further help to optimize the molecular analysis by suggesting the order in which the genes should be screened.


Assuntos
Febre Familiar do Mediterrâneo/diagnóstico , Febre Familiar do Mediterrâneo/genética , Índice de Gravidade de Doença , Adolescente , Adulto , Fatores Etários , Idoso , Algoritmos , Criança , Pré-Escolar , Estudos de Coortes , Proteínas do Citoesqueleto/genética , Diarreia/etiologia , Humanos , Lactente , Pessoa de Meia-Idade , Dor/etiologia , Fosfotransferases (Aceptor do Grupo Álcool)/genética , Pirina , Receptores Tipo I de Fatores de Necrose Tumoral/genética , Sensibilidade e Especificidade , Estomatite Aftosa/etiologia
5.
Exp Parasitol ; 114(3): 189-92, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16674944

RESUMO

Intracellular development of Cystoisospora belli was demonstrated in 4 different mammalian cell lines. Human ileocecal adenocarcinoma (HCT-8), epithelial carcinoma of lung (A549), Madin-Darby bovine kidney (MDBK), and African green monkey kidney (VERO) were exposed in vitro to C. belli sporozoites, which had been isolated from the feces of HIV-AIDS patients. Parasites invaded all the cellular types between 4 and 12h after exposure and multiplication was demonstrated after 24 h. Grater number of merozoites formed in VERO cells, followed by HCT-8. In the MDBK and HCT-8 cells, the parasitophorous vacuole was less evident and immobile merozoites were observed in the cytoplasm. In VERO cells, one or several parasitophorous vacuoles contained up to 16 mobile sporozoites. No oocysts were found in any of the cell types used. VERO cells may be suitable for studies of the interaction between parasite and host cells.


Assuntos
Infecções Oportunistas Relacionadas com a AIDS/parasitologia , Coccidiose/parasitologia , Sarcocystidae/crescimento & desenvolvimento , Infecções Oportunistas Relacionadas com a AIDS/complicações , Animais , Bovinos , Linhagem Celular , Linhagem Celular Tumoral , Chlorocebus aethiops , Coccidiose/complicações , Fezes/parasitologia , Humanos , Células Vero
7.
Parasitol Res ; 91(5): 384-9, 2003 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-14505041

RESUMO

The following heteroxenous and cyst-forming coccidian genera, Besnoitia, Cystoisospora, Frenkelia, Hammondia, Neospora, Sarcocystis and Toxoplasma have been compared biologically, and a key to determine their tissue cysts is provided.


Assuntos
Classificação , Coccídios , Cistos/parasitologia , Oocistos/fisiologia , Animais , Coccídios/classificação , Coccídios/crescimento & desenvolvimento , Humanos , Terminologia como Assunto
8.
Clin Exp Immunol ; 130(3): 484-8, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12452839

RESUMO

Hereditary periodic fever syndromes comprise a group of distinct disease entities linked by the defining feature of recurrent febrile episodes. Hyper IgD with periodic fever syndrome (HIDS) is caused by mutations in the mevalonate kinase (MVK) gene. The mechanisms by which defects in the MVK gene cause febrile episodes are unclear and there is no uniformly effective treatment. Mutations of the TNFRSF1A gene may also cause periodic fever syndrome (TRAPS). Treatment with the TNFR-Fc fusion protein, etanercept, is effective in some patients with TRAPS, but its clinical usefulness in HIDS has not been reported. We describe a 3-year-old boy in whom genetic screening revealed a rare combination of two MVK mutations producing clinical HIDS as well as a TNFRSF1A P46L variant present in about 1% of the population. In vitro functional assays demonstrated reduced receptor shedding in proband's monocytes. The proband therefore appears to have a novel clinical entity combining Hyper IgD syndrome with defective TNFRSF1A homeostasis, which is partially responsive to etanercept.


Assuntos
Antígenos CD/genética , Febre Familiar do Mediterrâneo/tratamento farmacológico , Imunoglobulina G/uso terapêutico , Leucócitos Mononucleares/metabolismo , Mutação , Receptores do Fator de Necrose Tumoral/antagonistas & inibidores , Receptores do Fator de Necrose Tumoral/genética , Receptores do Fator de Necrose Tumoral/uso terapêutico , Antígenos CD/sangue , Pré-Escolar , Análise Mutacional de DNA , Etanercepte , Febre Familiar do Mediterrâneo/genética , Febre Familiar do Mediterrâneo/metabolismo , Humanos , Masculino , Ácido Mevalônico/urina , Linhagem , Fosfotransferases (Aceptor do Grupo Álcool)/metabolismo , Receptores do Fator de Necrose Tumoral/sangue , Receptores Tipo I de Fatores de Necrose Tumoral
9.
Neth J Med ; 59(3): 118-25, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11583827

RESUMO

Hereditary periodic fever syndromes are defined by recurrent attacks of generalised inflammation for which no infectious or auto-immune cause can be identified. For most of these disorders, the molecular basis has recently been elucidated. This has opened the prospect of novel therapeutic approaches. Familial Mediterranean fever (FMF) is caused by mutations in the MEFV gene. Pathogenesis is poorly understood. The clinical severity is in part related to the mutations involved. Tumour necrosis factor receptor-1-associated periodic syndrome (TRAPS) is caused by mutations in the TNFRSF1A gene. This results in decreased serum levels soluble TNF-receptor leading to inflammation due to unopposed TNF-alpha action. Results of treatment with recombinant TNF-receptor analogues are promising. The hyper IgD periodic fever syndrome (HIDS) is caused by mutations in the MVK gene, leading to mevalonate kinase deficiency. The pathogenesis remains unclear. Muckle-Wells syndrome (MWS) and familial cold urticaria (FCU) are probably allelic disorders. The gene has been located, but not identified.


Assuntos
Febre Familiar do Mediterrâneo , Algoritmos , Árvores de Decisões , Diagnóstico Diferencial , Febre Familiar do Mediterrâneo/sangue , Febre Familiar do Mediterrâneo/classificação , Febre Familiar do Mediterrâneo/diagnóstico , Febre Familiar do Mediterrâneo/genética , Febre Familiar do Mediterrâneo/terapia , Humanos , Inflamação , Mutação/genética , Receptores do Fator de Necrose Tumoral/sangue , Receptores do Fator de Necrose Tumoral/genética , Receptores do Fator de Necrose Tumoral/uso terapêutico , Índice de Gravidade de Doença
10.
Arch Dis Child ; 85(2): 158-9, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11466192

RESUMO

BACKGROUND: The hyperimmunoglobulinaemia D and periodic fever syndrome is a hereditary periodic fever, caused by deficiency of the enzyme mevalonate kinase. It is unclear how this defect leads to recurrent fever episodes. AIM: To assess the involvement of cysteinyl leukotrienes in the pathogenesis of fever attacks as reflected by urinary leukotriene E(4) (LTE(4)) excretion. METHODS: Urinary LTE(4) was measured in seven patients while febrile and afebrile. RESULTS: LTE(4) was raised during fever in all subjects (46-199 nmol/mol creatinine, mean 92; normal <40). Urinary LTE(4) was normal between attacks, as well as in normal children with fever as a result of miscellaneous causes. CONCLUSION: Our results suggest that cysteinyl leukotrienes play a role in the pathophysiology of this disorder. As no effective treatment is yet available, leukotriene receptor antagonists might offer a new therapeutic approach for patients with the hyperimmunoglobulinaemia D and periodic fever syndrome.


Assuntos
Febre Familiar do Mediterrâneo/urina , Hipergamaglobulinemia/urina , Imunoglobulina D , Leucotrieno E4/urina , Adolescente , Criança , Cromatografia Gasosa , Cromatografia Líquida de Alta Pressão , Humanos , Espectrometria de Massas , Ácido Mevalônico/urina , Técnica de Diluição de Radioisótopos
11.
Lancet ; 355(9199): 201-2, 2000 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-10675124

RESUMO

A fatal measles case in an immunocompromised Indonesian child was associated with nosocomial transmission to health care workers. The virus isolated proved to represent a new genotype within clade G.


Assuntos
Infecção Hospitalar/virologia , Vírus do Sarampo/genética , Sarampo/transmissão , Criança , Feminino , Humanos , Hospedeiro Imunocomprometido/imunologia , Indonésia/etnologia , Sarampo/imunologia , Sarampo/virologia , Países Baixos/epidemiologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/imunologia
12.
J Parasitol ; 85(4): 657-62, 1999 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10461945

RESUMO

Infection and immunity to toxoplasmosis induced by the RH strain of Toxoplasma gondii was compared in Sprague-Dawley (SD) and Wistar rats and in outbred Swiss Webster mice. All rats injected with up to 1,000,000 RH-strain tachyzoites remained clinically normal, whereas mice injected with only 1 live tachyzoite died of acute toxoplasmosis. Rats could be infected with 1 tachyzoite of the RH strain as shown by antibody development and by bioassay in mice. However, after 8 days, RH-strain organisms were recovered only inconsistently from SD and Wistar rat brains. Contrary to a report of sterile immunity to T. gondii infection in rats after immunization with live RH tachyzoites, we found infection immunity after challenge with the VEG strain. Toxoplasma gondii tissue cysts of the VEG strain could be recovered from most SD and Wistar rats, first injected with live RH-strain tachyzoites and then challenged with oocysts of the VEG strain. Our RH strain, and probably many others, passed for 50+ yr as tachyzoites has lost not only the capacity to form oocysts, but also shows a marked reduction or absence of tissue cyst (bradyzoites) formation.


Assuntos
Toxoplasma/imunologia , Toxoplasmose Animal/imunologia , Animais , Anticorpos Antiprotozoários/sangue , Suscetibilidade a Doenças , Feminino , Camundongos , Ratos , Ratos Sprague-Dawley , Ratos Wistar , Especificidade da Espécie , Toxoplasma/patogenicidade
13.
Oncogene ; 18(18): 2901-7, 1999 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-10362261

RESUMO

In order to identify the alternative pathways which may substitute for the p53 function during embryogenesis, we have focused our studies on p53 -/- normally developing mouse embryos that survived a genotoxic stress. We assumed that under these conditions p53-independent pathways, which physiologically control genomic stability, are enhanced. We found that while p53 +/+ mouse embryos elicited, as expected, a p53-dependent apoptosis, p53-/- normally developing mice exhibited an accentuated p53-independent apoptotic response. The p53-dependent apoptosis detected in p53+/+ embryos, was an immediate reaction mostly detected in the brain, whereas the p53-independent apoptosis was a delayed reaction with a prominent pattern observed in epithelial cells of most organs in the p53-deficient mice only. These results suggest that in the absence of p53-dependent apoptosis, which is a fast response to damaged DNA, p53-independent apoptotic pathways, with slower kinetics, are turned on to secure genome stability.


Assuntos
Apoptose/genética , Embrião de Mamíferos/citologia , Desenvolvimento Embrionário e Fetal/genética , Proteína Supressora de Tumor p53/genética , Animais , Embrião de Mamíferos/efeitos da radiação , Feminino , Raios gama , Masculino , Camundongos , Camundongos Endogâmicos , Camundongos Knockout , Defeitos do Tubo Neural/genética , Estresse Fisiológico , Proteína Supressora de Tumor p53/metabolismo
14.
Vet Parasitol ; 77(1): 1-32, 1998 May.
Artigo em Inglês | MEDLINE | ID: mdl-9652380

RESUMO

We critically review and summarize information on the prevalence of Toxoplasma gondii infections in rats, mainly Rattus norvegicus, and their possible role as a source of infection for larger carnivores and omnivores. We also review information on immunology and natural resistance, contributing to the model value of rats in the analysis of human infection. Rats can be successfully infected with oocysts (sporozoites), tissue cysts (bradyzoites), and tachyzoites. Even adult rats, that are resistant to clinical toxoplasmosis, can be infected orally with a few oocysts or tissue cysts. Infections with tachyzoites of the RH strain are highly variable. Congenital transmission of T. gondii occurs at a high rate when rats are infected during pregnancy. Congenitally infected rats can harbor viable T. gondii in the absence of detectable antibodies to T. gondii and rats with low antibody titers may harbor few or no organisms. The isolation of viable T. gondii by bioassay is the only reliable means to determine persistence of chronic T. gondii infection in feral rats. No evidence was found for maintenance of T. gondii in rats by vertical transmission in the absence of cats.


Assuntos
Modelos Animais de Doenças , Muridae/parasitologia , Doenças dos Roedores/epidemiologia , Toxoplasmose Animal/epidemiologia , Animais , Feminino , Interações Hospedeiro-Parasita , Transmissão Vertical de Doenças Infecciosas/veterinária , Gravidez , Prevalência , Ratos , Doenças dos Roedores/imunologia , Doenças dos Roedores/transmissão , Toxoplasmose Animal/imunologia , Toxoplasmose Animal/transmissão
15.
Rev. Soc. Bras. Med. Trop ; 31(2): 163-171, mar.-abr. 1998. ilus, tab
Artigo em Português | LILACS | ID: lil-464110

RESUMO

Em 22 pacientes com sorologia positiva para o vírus da imunodeficiência humana, com ou sem síndrome da imunodeficiência adquirida, dos quais 7 com meningoencefalite toxoplásmica e 15 com meningoencefalite chagásica associadas, procuraram-se dados diferenciais, entre as duas encefalopatias, tanto à anatomia patológica quanto à tomografia computadorizada do crânio. Os resultados observados e os dados da literatura nos permitiram concluir que enquanto na meningoencefalite necrosante focal por Toxoplasma gondii o acometimento dos núcleos da base é freqüente, na meningoencefalite necrosante focal causada pelo Trypanosoma cruzi, lesões dessas estruturas parecem não ocorrer ou ser excepcionais. De outro lado, o acometimento da substância branca parece nitidamente maior na meningoencefalite chagásica que na meningoencefalite toxoplásmica, ao passo que o parasitismo e a hemorragia do tecido nervoso, bem como as lesões das bainhas de mielina são mais freqüentes e intensos na meningoencefalite causada pelo Trypanosoma cruzi que naquela por Toxoplasma.


Twenty-two HIV+ patients with encephalitis were studied. Of these, 7 had meningoencephalitis due to Toxoplasma gondii (MT) and 15 due to Trypanosoma cruzi (MC). Pathologic and computerized axial tomography (CAT) changes were compared. We found that focal necrotizing encephalitis due to Toxoplasma involved the cerebral cortex and the basal ganglia, whereas lesions due to Trypanosoma cruzi were centered in the white matter, sometimes extending into the cortex. Hemorrhages, myelin lesions and organisms were more pronounced in chagasic than in toxoplasmic encephalitis. These findings are consistent with the literature reviewed.


Assuntos
Humanos , Doença de Chagas/diagnóstico , Meningoencefalite/parasitologia , Síndrome da Imunodeficiência Adquirida/complicações , Toxoplasmose/diagnóstico , Diagnóstico Diferencial , Doença de Chagas/parasitologia , Doença de Chagas/patologia , Meningoencefalite/patologia , Meningoencefalite , Toxoplasmose/parasitologia , Toxoplasmose/patologia , Toxoplasmose
16.
Parasitol Res ; 83(1): 1-5, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9000224

RESUMO

We review herein studies concerning the genomic polymorphism of Toxoplasma gondii including 3 clones (1 linked with mouse pathogenicity), 5 zymodemes, and 13 schizodemes. Because mutations occur with some frequency and several allelic configurations are present in isolates grown in the same environment, we conclude that many of the mutations may not be affected by selection pressure. However, the gametocyte-forming ability is under selection pressure from the hose and depends on the development of bradyzoites in tissue cysts. After prolonged multiplication exclusively in the tachyzoite stage in mice and, possibly, in patients the gametocyte-forming ability may be lost. To avoid this genomic change, isolates should be passed in the laboratory, permitting bradyzoite and tissue-cyst formation. Mouse pathogenicity is selected for during mouse passage. We find no major genomic instability justifying species or subspecies distinctions.


Assuntos
Frequência do Gene , Polimorfismo Genético , Toxoplasma/genética , Animais , Gametogênese , Genoma de Protozoário , Humanos , Camundongos , Modelos Genéticos , Mutagênese , Toxoplasma/classificação , Toxoplasma/patogenicidade
17.
J Infect Dis ; 174(5): 1091-7, 1996 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8896514

RESUMO

Tumor necrosis factor (TNF) is thought to play a key role in the pathogenesis of cerebral malaria. A double-blind, placebo-controlled trial of an anti-TNF monoclonal antibody (B-C7) comprised 610 Gambian children with cerebral malaria, with mortality and residual neurologic sequelae as primary study end points. Sixty (19.9%) of 302 children who received B-C7 died compared with 64 (20.8%) of 308 children who received placebo (adjusted odds ratio [OR], 0.90; 95% confidence interval [CI], 0.57-1.42). Residual neurologic sequelae were detected in 15 (6.8%) of 221 survivors from the B-C7 group and in 5 (2.2%) of 225 survivors of the placebo group (adjusted OR, 3.35; 95% CI, 1.08-10.4). The monoclonal antibody used in this study did not improve survival in cerebral malaria and was associated with a significant increase in neurologic sequelae. A possible explanation of the latter observation is that the antibody acts to retain TNF within the circulation and thereby prolongs its effects on vascular endothelium.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Malária Cerebral/terapia , Fator de Necrose Tumoral alfa/fisiologia , Anticorpos Monoclonais/efeitos adversos , Criança , Pré-Escolar , Método Duplo-Cego , Feminino , Humanos , Lactente , Malária Cerebral/complicações , Malária Cerebral/mortalidade , Masculino , Óxido Nítrico/fisiologia
19.
Med Pediatr Oncol ; 25(6): 473-4, 1995 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-7565311

RESUMO

Carboplatin has been reported to cause acute renal failure when administered in high doses to adult patients. We report a 4 1/2-year-old girl who was treated with high-dose carboplatin for metastatic parameningeal embryonal rhabdomyosarcoma. Acute renal failure developed followed by a slow partial recovery of renal function. Possible contributing factors are discussed.


Assuntos
Injúria Renal Aguda/induzido quimicamente , Carboplatina/efeitos adversos , Pré-Escolar , Feminino , Humanos , Neoplasias Meníngeas/tratamento farmacológico , Neoplasias Meníngeas/secundário , Rabdomiossarcoma Embrionário/tratamento farmacológico , Rabdomiossarcoma Embrionário/secundário
20.
Am J Trop Med Hyg ; 53(5): 448-57, 1995 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-7485702

RESUMO

We conducted a survey of 760 Amerindian children 2-12 years of age in the Bayano and San Blas areas of Panama in 1991 to determine the prevalence of serum antibodies to Toxoplasma gondii and the importance of hypothesized risk factors in human-induced native and sylvatic conditions, which have had few environmental changes, as opposed to rural and urban areas in Panama previously studied. The overall prevalence of infection ranged between 0% and 42.5%. No age curve was detected, indicative of nonconstant transmission. Only two hypothesized risk factors, floor type and having cats inside the house, were significantly associated with the presence of antibodies in some of the communities. Antibody prevalence appeared to be associated more with the community of residence than with any specific behavior. The risk factor of importance may be the level of oocyst contamination, since infection by tissue cysts in meat was excluded. On three of the nine islands studied, no antibody was detected in the children or the cats. It would appear that T. gondii is not present on these islands. Although the data did not support the importance of many of the hypothesized risk factors, the study is consistent with the theory of transmission by oocysts and the importance of cats in transmission.


Assuntos
Indígenas Centro-Americanos , Toxoplasmose/epidemiologia , Animais , Anticorpos Antiprotozoários/sangue , Doenças do Gato/epidemiologia , Doenças do Gato/transmissão , Gatos , Criança , Pré-Escolar , Fatores de Confusão Epidemiológicos , Feminino , Humanos , Entrevistas como Assunto , Masculino , Carne , Análise Multivariada , Panamá/epidemiologia , Prevalência , Fatores de Risco , População Rural , Toxoplasma/imunologia , Toxoplasmose Animal/epidemiologia , Toxoplasmose Animal/transmissão , Abastecimento de Água
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