Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 26
Filtrar
Mais filtros











Base de dados
Intervalo de ano de publicação
1.
Transplantation ; 71(9): 1343-6, 2001 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-11397975

RESUMO

Cerebral phaeohyphomycosis is a rare disease caused by dematiaceous (darkly pigmented) fungi. Cladophialophora species are highly neurotropic, and Cladophialophora bantiana (synonym=Xylohypha bantiana or C. trichoides) is the most commonly identified agent. Most reported cases of cerebral phaeohyphomycosis have occurred in immunocompetent patients; however, some case reports and experimental data have suggested that cellular immune deficiency is a risk factor. We report a case of pulmonary and cerebral phaeohyphomycosis in a cardiac transplant patient due to a newly identified species of Cladophialophora. Optimal management includes both antifungal therapy and surgery.


Assuntos
Encefalopatias/microbiologia , Infecções Fúngicas do Sistema Nervoso Central/imunologia , Adulto , Feminino , Humanos , Imunocompetência , Micoses/imunologia , Phialophora/isolamento & purificação
2.
Infect Immun ; 69(3): 1889-94, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11179369

RESUMO

Hemolytic uremic syndrome (HUS) is associated with intestinal infection by enterohemorrhagic Escherichia coli strains that produce Shiga toxins. Globotriaosylceramide (Gb3) is the functional receptor for Shiga toxin, and tumor necrosis factor alpha (TNF-alpha) upregulates Gb3 in both human macrovascular umbilical vein endothelial cells and human microvascular brain endothelial cells. TNF-alpha treatment enhanced Shiga toxin binding and sensitivity to toxin. This upregulation was specific for Gb3 species containing normal fatty acids (NFA). Central nervous system (CNS) pathology in HUS could involve cytokine-stimulated elevation of endothelial NFA-Gb3 levels. Differential expression of Gb3 species may be a critical determinant of Shiga toxin toxicity and of CNS involvement in HUS.


Assuntos
Barreira Hematoencefálica/efeitos dos fármacos , Endotélio Vascular/efeitos dos fármacos , Toxina Shiga/farmacologia , Triexosilceramidas/biossíntese , Fator de Necrose Tumoral alfa/farmacologia , Relação Dose-Resposta a Droga , Sinergismo Farmacológico , Humanos
3.
Kidney Int ; 54(4): 1117-27, 1998 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9767527

RESUMO

BACKGROUND: Shiga toxin 1 (Stx1) is a causative agent in hemolytic uremic syndrome (HUS). Its receptor, the glycosphingolipid globotriaosylceramide (Gb3), is expressed on cultured human endothelial and mesangial cells. Mesangial cell injury in HUS ranges from mild cellular edema to severe mesangiolysis and eventual glomerulosclerosis. We hypothesized that, in addition to endothelial cells, mesangial cells are targets of Stx1. METHODS: Human mesangial cells were exposed to Stx1. Protein synthesis was measured using [35S]-methionine/cysteine. Cell viability was measured as the lysosomal uptake of Neutral Red. Monocyte chemotactic peptide (MCP-1) mRNA and protein were analyzed by Northern blotting and ELISA. RESULTS: Stx1 (0.25 to 2500 ng/ml) resulted in a dose-dependent inhibition of protein synthesis. This effect of Stx1 was potentiated by preincubation of the cells with interleukin-1alpha (IL-1alpha; 2 ng/ml) or tumor necrosis-alpha (TNF-alpha; 500 U/ml). Stx1 had little effect on mesangial cell viability during the first 24 hours of exposure to Stx1. However, prolonged incubation with Stx1 for 48 and 72 hours resulted in a 68% and 80% decrease in cell-viability, respectively. Stx1 elicited a dose and time dependent increase in the levels of MCP-1 mRNA, an effect that was potentiated by preincubation with IL-1alpha. CONCLUSION: These data indicate that mesangial cells are susceptible to the effects of Stx1 in vitro. Stx1 exerts a spectrum of biologic effects on mesangial cells ranging from activation of chemokine genes to a lethal toxic injury. Immunoinflammatory cytokines potentiate the effects of Stx1. Thus, glomerular pathology in HUS may also result from a direct effect of Stx1 on mesangial cells.


Assuntos
Toxinas Bacterianas/toxicidade , Mesângio Glomerular/efeitos dos fármacos , Mesângio Glomerular/metabolismo , Tamanho Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Quimiocina CCL2/biossíntese , Quimiocina CCL2/genética , DNA/biossíntese , Endotélio Vascular/efeitos dos fármacos , Mesângio Glomerular/citologia , Síndrome Hemolítico-Urêmica/etiologia , Humanos , Interleucina-1/farmacologia , Modelos Biológicos , Biossíntese de Proteínas , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Toxinas Shiga , Fator de Necrose Tumoral alfa/farmacologia
4.
Clin Infect Dis ; 27(1): 205-8, 1998 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9675477

RESUMO

We present clinical, bacteriologic, and pathological findings for four patients with AIDS and cutaneous miliary tuberculosis. All patients had generalized tuberculosis with hematogenous dissemination to multiple organs including the skin. Microscopic examination of the skin lesions revealed ill-formed or no granulomata, extensive necrosis, and numerous acid-fast bacilli. Mycobacterium tuberculosis was detected in the skin lesions by cultures for three patients and by polymerase chain reaction for one. Three of the isolates were resistant to at least isoniazid and rifampin, and one was susceptible to these drugs. The outcome was rapidly fatal for the three patients with multidrug-resistant tuberculosis. This report draws attention to the reappearance of a once-rare manifestation of disseminated tuberculosis which, in the setting of advanced human immunodeficiency virus disease, may offer the first indication of infection with multidrug-resistant M. tuberculosis and a poor prognosis.


Assuntos
Síndrome da Imunodeficiência Adquirida/complicações , Tuberculose Cutânea/complicações , Tuberculose Miliar/complicações , Tuberculose Resistente a Múltiplos Medicamentos/complicações , Adulto , Evolução Fatal , HIV-1 , Humanos , Masculino , Mycobacterium tuberculosis/isolamento & purificação , Tuberculose Cutânea/diagnóstico , Tuberculose Miliar/diagnóstico , Tuberculose Resistente a Múltiplos Medicamentos/diagnóstico
5.
Artif Organs ; 22(1): 87-94, 1998 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9456234

RESUMO

In vivo characterization studies were performed to compare the dynamic in vivo performance of the Penn State/3M Health Care electric total artificial heart to existing in vitro data. Fully implanted systems were utilized including the artificial heart, controller, backup batteries, compliance chamber, and transcutaneous energy transmission. Catheters were implanted to measure central venous pressure (CVP), left atrial pressure (LAP), right atrial pressure (RAP), pulmonary artery pressure (PAP), and aortic pressure (AoP). Cardiac output (CO) was determined from the implanted controller, and systemic vascular resistance (SVR) was calculated. Steady state data were collected for each animal along with data regarding the transient responses to changes in preload and afterload. Preload was manipulated through volume changes. Afterload changes were accomplished through vasoactive agents. Increased preload caused little change in cardiac output because the pump output was nearly maximum at baseline. LAP, AoP, and SVR increased with increasing RAP. Decreased preload caused a reduction in CO, LAP, and SVR. Afterload increase resulted in a slight decrease in flow and an increase in system power and SVR. Afterload reduction was accompanied by a decrease in preload and a concomitant reduction in flow. Overall, the system response was similar to the response observed in vitro.


Assuntos
Coração Artificial , Animais , Pressão Sanguínea/fisiologia , Débito Cardíaco/fisiologia , Bovinos , Hematócrito , Testes de Função Renal , Testes de Função Hepática , Pressão Propulsora Pulmonar/fisiologia , Análise de Sobrevida , Resistência Vascular/fisiologia
6.
Pediatr Infect Dis J ; 14(7): 594-8, 1995 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-7567288

RESUMO

Hemolytic uremic syndrome (HUS) is thought to be a vascular endothelial injury disease. The mechanism of injury is unknown although verocytotoxins (Shiga-like toxins (SLTs)) are known to be associated with it. Recent evidence suggests that in vitro treatment of some endothelial cells with tumor necrosis factor alpha (TNF-alpha) dramatically increases their susceptibility to SLTs. We studied 25 children with HUS, 63 children with SLT-positive bloody diarrhea, 62 children with bloody diarrhea not associated with SLTs and 39 children admitted for elective surgery, included as an age- and season-matched control group. The TNF-alpha concentrations were found to be significantly elevated in children with HUS (range, 1 to 95 pg/ml; geometric mean, 32.2 pg/ml) compared with the healthy controls (range, 0 to 53 pg/ml; mean, 12.5 pg/ml; P < 0.001). Because it is hypothesized that TNF-alpha elevation might precede development of HUS, we also studied children with blood diarrhea. The TNF-alpha serum concentrations were significantly higher during the first 10 days after onset of bloody diarrhea than after the first 10 days (P < 0.02). Such elevation could be associated with vascular endothelial glycolipid receptor up-regulation and increased susceptibility to the effects of SLTs.


Assuntos
Síndrome Hemolítico-Urêmica/sangue , Síndrome Hemolítico-Urêmica/fisiopatologia , Fator de Necrose Tumoral alfa/análise , Argentina , Estudos de Casos e Controles , Pré-Escolar , Diarreia/etiologia , Fezes/microbiologia , Feminino , Síndrome Hemolítico-Urêmica/complicações , Humanos , Imunoensaio , Lactente , Masculino , Prognóstico
7.
Clin Immunol Immunopathol ; 70(3): 245-50, 1994 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-7508835

RESUMO

Immunophenotypic changes in peripheral blood mononuclear cells were analyzed by flow cytometry in several patient groups positive for cocaine in their urine. Single- and dual-color immunofluorescence staining was performed to examine total numbers of NK, T, and B cells, as well as the coexpression of surface molecules on T cells associated with memory function, helper/inducer capacity, and activation status. In addition, levels of several serum proteins (including immunoglobulins) and other demographic variables were evaluated. Our results show that cocaine-intoxicated patients display reductions in the total percentage of CD4+ T cells and increases in the number of NK cells. Dramatic shifts within certain T cell subpopulations were also observed. In particular, there appeared to be a preferential stimulation of "activated" T cells as indicated by increased levels of class II+ CD4 and CD8 T cells and IL2r+ CD4 T cells. "Memory" CD8+ T cell subpopulations (i.e., CD45RO+) were reduced in the cocaine-positive patients, whereas CD45R+/CD8+ T cells were accordingly increased in the same individuals. In some cases, direct correlation could be established between certain T cell percentages and cocaine levels. None of the serum protein levels measured appeared to be influenced by cocaine. These findings demonstrate that cocaine utilization is associated with variations in levels of certain T cell subpopulations and other immune cells. This may represent a disruption of particular immunologic cell networks which could ultimately influence host resistance to infection and malignancy.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Cocaína , Células Matadoras Naturais/imunologia , Transtornos Relacionados ao Uso de Substâncias/imunologia , Proteínas de Fase Aguda/análise , Adulto , Relação CD4-CD8 , Cocaína/urina , Proteínas do Sistema Complemento/análise , Feminino , Citometria de Fluxo , Humanos , Imunoglobulinas/sangue , Memória Imunológica , Masculino , Gravidez , Transtornos Relacionados ao Uso de Substâncias/complicações , Subpopulações de Linfócitos T/imunologia
8.
J Clin Invest ; 92(5): 2110-6, 1993 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8227326

RESUMO

We have examined the hypothesis that TNF may play a pathogenetically important role in the hemolytic uremic syndrome. Specifically, we considered the possibility that shigatoxin, which eventuates this syndrome, might induce TNF biosynthesis, and/or that TNF and shigatoxin might sensitize animals, each to the toxic effects of the other agent. Shigatoxin was found to sensitize mice to the lethal effect of LPS and to the lethal effect of TNF. On the other hand, pretreatment of animals with either TNF or LPS did not noticeably sensitize mice to the lethal effect of shigatoxin. Intraperitoneal injections of shigatoxin did not induce the production of detectable quantities of TNF in the plasma of mice. When shigatoxin was injected into transgenic mice bearing a chloramphenicol acetyltransferase (CAT) reporter gene that indicates TNF synthesis, CAT activity was induced within the kidney, but not in other tissues. We therefore conclude that shigatoxin acts to induce TNF synthesis within the kidney, and at the same time increases renal sensitivity to the toxic effects of TNF. While this mouse model does not reproduce the hemolytic uremic syndrome as it occurs in humans, it does suggest that local synthesis of TNF within the kidney may contribute to renal injury induced by shigatoxin.


Assuntos
Toxinas Bacterianas/farmacologia , Regulação da Expressão Gênica , Rim/efeitos dos fármacos , Fator de Necrose Tumoral alfa/biossíntese , Animais , Cloranfenicol O-Acetiltransferase/biossíntese , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Genes Reporter , Síndrome Hemolítico-Urêmica/etiologia , Rim/patologia , Lipopolissacarídeos/farmacologia , Camundongos , Camundongos Endogâmicos C3H , Camundongos Transgênicos , Modelos Biológicos , Toxinas Shiga , Fator de Necrose Tumoral alfa/genética
9.
Ann Intern Med ; 117(3): 184-90, 1992 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-1616212

RESUMO

OBJECTIVE: To determine the clinical manifestations of patients with human immunodeficiency virus (HIV) infection and tuberculosis caused by multiple-drug-resistant bacilli compared with those with single-drug-resistant or susceptible bacilli. DESIGN: Descriptive, case-control, and cohort studies. SETTING: A large urban teaching hospital. PATIENTS: Sixty-two patients with tuberculosis caused by multiple-drug-resistant bacilli (cases) and 55 patients with tuberculosis caused by single-drug-resistant or susceptible bacilli (controls). MEASUREMENTS: Characteristics of clinical presentation, radiographs, pathologic abnormalities, antituberculosis treatment, and clinical course. RESULTS: Twenty cases (32%) had concomitant pulmonary and extrapulmonary disease at presentation compared with 9 controls (16%; odds ratio, 2.4; 95% CI, 1.0 to 5.9). More cases had alveolar infiltrates (76%; odds ratio, 3.6; CI, 1.2 to 11.4), interstitial infiltrates with a reticular pattern (67%; odds ratio, 7.8; CI, 1.0 to 83.5), and cavitations (18%; odds ratio, 6.6; CI, 0.8 to 315.3) on initial chest radiographs compared with controls (49%, 19%, and 3%, respectively). Pathologic specimens from cases showed extensive necrosis, poor granuloma formation, marked inflammatory changes with a predominance of neutrophils, and abundant acid-fast bacilli. Twenty-five cases received two or more effective antituberculosis drugs for more than 2 months. Only 2 cases had three consecutive negative cultures for Mycobacterium tuberculosis; one patient died within 1 day of the last negative culture, and the other had positive cultures 496 days later. The remaining 23 cases had persistently or intermittently positive cultures despite therapy. The clinical course of these cases suggested overwhelming miliary tuberculosis with involvement of the lungs (77%), pleura (15%), stool (34%), meninges (13%), bone marrow (16%), blood (10%), lymph nodes (10%), and skin (8%). The median survival time was 2.1 months for cases compared with 14.6 months for controls (P = 0.001, log-rank test). CONCLUSIONS: Tuberculosis caused by multiple-drug-resistant bacilli in patients with HIV infection is associated with widely disseminated disease, poor treatment response with an inability to eradicate the organism, and substantial mortality.


Assuntos
Síndrome da Imunodeficiência Adquirida/complicações , Antituberculosos/farmacologia , Mycobacterium tuberculosis/efeitos dos fármacos , Tuberculose Pulmonar/microbiologia , Adulto , Antituberculosos/administração & dosagem , Estudos de Casos e Controles , Estudos de Coortes , Resistência Microbiana a Medicamentos , Quimioterapia Combinada , Feminino , Humanos , Masculino , Modelos de Riscos Proporcionais , Análise de Sobrevida , Resultado do Tratamento , Tuberculose Pulmonar/complicações , Tuberculose Pulmonar/tratamento farmacológico , Tuberculose Pulmonar/patologia
10.
Infect Immun ; 60(4): 1613-7, 1992 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-1548083

RESUMO

Enterohemorrhagic Escherichia coli (EHEC) produce Shiga-like toxins and attach to certain tissue culture cells. T84 cells are human colonic carcinoma cells. Unlike previously studied cell lines, T84 cells grown on collagen-coated surfaces polarize and produce tight junctions and desmosomes, forming a colonic epithelial cell layer in vitro. The purpose of this study was to examine the attachment of EHEC strains to the T84 cell line as a possibly more relevant in vitro model of EHEC adherence. Twelve EHEC strains were grown overnight in Penassay broth, suspended in minimal essential medium with and without 0.5% mannose, and incubated for 1 to 3 h with 5- to 7-day-old T84 cell monolayers grown on collagen-coated coverslips. The bacteria were removed, and attachment was quantitated microscopically. For both E. coli O157:H7 and other EHEC serotypes, there were marked differences in adherence between strains (range of 152 to 3 bacteria per oil immersion field). Mannose partially inhibited the adherence of some EHEC strains. Adherence to the T84 cells appeared to be related to the amount of pili present and not to the serotype. Electron micrographs showed that a highly adherent strain (strain 43-12) tended to form microcolonies in the area of tight junctions on the T84 cell monolayers. In addition, the attachment of these EHEC strains to T84 cells correlated with their ability to adhere to isolated rabbit colonocytes (r = 0.91, P = 0.00004; without mannose) (r = 0.60, P = 0.04; with mannose). These data show that there are EHEC strain-related differences in adherence which can be demonstrated in a human-derived colonic epithelial cell line (T84) and that these cells can be used to study EHEC adherence.


Assuntos
Aderência Bacteriana , Colo/microbiologia , Escherichia coli/patogenicidade , Aderência Bacteriana/efeitos dos fármacos , Linhagem Celular , Epitélio/microbiologia , Humanos , Manose/farmacologia , Microscopia Eletrônica
11.
Arch Ophthalmol ; 109(2): 266-71, 1991 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-1847043

RESUMO

Members of the herpesvirus family, cytomegalovirus (CMV), Epstein-Barr virus (EBV), and herpes simplex virus (HSV), have been recognized as causal agents of chorioretinal inflammatory diseases. We investigated the use of the polymerase chain reaction for the detection of CMV, HSV, and EBV genomes in aqueous, subretinal fluid, and vitreous specimens in patients with clinically diagnosed CMV retinitis. Cytomegalovirus but not HSV or EBV genomic sequences were detected in all of these clinical specimens. We also investigated 18 normal aqueous and eight normal vitreous specimens obtained from patients undergoing cataract or vitrectomy surgery. Cytomegalovirus, HSV, and EBV DNA were not detected in any of the normal aqueous specimens. There was one weakly positive CMV normal vitreous, but none was HSV or EBV positive by the polymerase chain reaction. These results indicate that the polymerase chain reaction may be useful as a rapid and sensitive diagnostic technique to aid in the confirmation of clinical observations.


Assuntos
Humor Aquoso/microbiologia , DNA Viral/análise , Herpesviridae/isolamento & purificação , Reação em Cadeia da Polimerase , Corpo Vítreo/microbiologia , Síndrome da Imunodeficiência Adquirida/microbiologia , Anticorpos Antivirais/sangue , Autorradiografia , Citomegalovirus/genética , Citomegalovirus/isolamento & purificação , Infecções por Citomegalovirus/microbiologia , Herpesviridae/genética , Herpesvirus Humano 4/genética , Herpesvirus Humano 4/isolamento & purificação , Humanos , Reação em Cadeia da Polimerase/métodos , Retinite/microbiologia , Simplexvirus/genética , Simplexvirus/isolamento & purificação
12.
Curr Eye Res ; 9(6): 569-81, 1990 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-2167192

RESUMO

Herpetic ocular disease is one of the major causes of corneal blindness. Clinical diagnosis of corneal disease is based principally on corneal appearance. However, abnormal morphology of the corneal epithelium (CE) is not an indicator for the presence of a herpes virus. Further, it has not been established if herpes viruses are present in normal corneal epithelial tissue. In these studies, the polymerase chain reaction was used to evaluate normal and diseased corneal epithelium for the presence of herpes simplex virus type 1 (HSV-1), Epstein-Barr virus (EBV) and cytomegalovirus (CMV) genomic sequences. Thirty-two normal corneal epithelium specimens obtained from cadavers shortly after death were analyzed for HSV-1, EBV and CMV genomic sequences. Three of the 32 normal CE specimens were positive for amplified EBV DNA, 1 was positive for HSV-1 DNA, and none was positive for CMV DNA. We also tested eight herpetic dendritic lesions of which 3 were HSV-1 culture and PCR positive. The remaining five dendritic lesions were HSV-1 culture and PCR negative. Since these lesions were not evaluated for other herpesviruses, the etiology of these dendritic lesions is unknown. Six corneal epithelium samples from HIV-infected donors were negative for EBV, CMV and HSV-1 amplified sequences. Positive EBV, CMV and HSV-1 serology on all normal donors and on donors with clinically apparent disease did not correlate with positive PCR results. The results of these studies suggest that EBV and HSV-1 DNA can be amplified from a small percentage of apparently normal corneal epithelium.


Assuntos
Córnea/microbiologia , DNA Viral/análise , Amplificação de Genes , Ceratite Dendrítica/microbiologia , Reação em Cadeia da Polimerase , Simplexvirus/isolamento & purificação , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Antivirais/análise , Sequência de Bases , Southern Blotting , Citomegalovirus/genética , Citomegalovirus/isolamento & purificação , Epitélio/microbiologia , Feminino , Imunofluorescência , Herpesvirus Humano 4/genética , Herpesvirus Humano 4/isolamento & purificação , Humanos , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Hibridização de Ácido Nucleico , Sondas de Oligonucleotídeos , Valor Preditivo dos Testes , Simplexvirus/genética
13.
J Clin Microbiol ; 28(5): 1026-32, 1990 May.
Artigo em Inglês | MEDLINE | ID: mdl-2161862

RESUMO

Epstein-Barr virus (EBV) has been implicated in several ocular diseases; however, detection of the EBV genome in ocular tissues has not been documented. We report the detection of amplified EBV genomic sequences in 11 of 26 normal lacrimal gland DNA samples by using the polymerase chain reaction. Serum was available for 19 of the lacrimal gland donors. All 19 were EBV seropositive, although of the 19 lacrimal gland-seropositive patients, EBV sequences were detected in only 10 of the samples. Further, amplified EBV sequences were not detected in circulating lymphocyte DNA from normal seropositive volunteers, most likely because of the low frequency of circulating EBV-infected B cells. Amplification of EBV from cadaver lacrimal gland DNA was possible with minute quantities of DNA, whereas peripheral blood mononuclear cell DNA from normal volunteers did not amplify EBV sequences. Interestingly, the peripheral blood mononuclear cell polymerase chain reactions contained approximately 100 times more DNA than the lacrimal gland polymerase chain reactions. We conclude that the lacrimal gland may be a site for EBV persistence and that positive EBV serology is not an indicator of which individuals may have EBV harbored within their lacrimal glands.


Assuntos
Herpesvirus Humano 4/isolamento & purificação , Aparelho Lacrimal/microbiologia , Sequência de Bases , Sondas de DNA , DNA Viral/genética , Desoxirribonuclease BamHI , Genes Virais , Herpesvirus Humano 4/genética , Humanos , Linfócitos/microbiologia , Dados de Sequência Molecular , Reação em Cadeia da Polimerase
14.
J Pediatr ; 113(6): 1008-14, 1988 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-3057156

RESUMO

The pathogenesis of primary (classic) hemolytic-uremic syndrome (HUS) is thought to be related to cytotoxin-producing enteric pathogens such as Shigella dysenteriae serotype 1 and Escherichia coli serotypes O157:H7 and 026:H11. The relevant cytotoxins include Shiga toxin and the closely related Shiga-like toxins (SLTs) produced by some E. coli strains. Intravenously administered immune globulin (IVIG) therapy has been reported to be beneficial in a few children with HUS. We therefore examined commercially available immune globulin preparations for the presence of anticytotoxin-neutralizing antibodies. Cytotoxicity and neutralization of the HUS-associated cytotoxins were quantitatively determined by means of a (3H)thymidine-labeled HeLa cell assay. The immune globulin preparations tested almost completely neutralized Shiga toxin (produced by S. dysenteriae 1) and SLT-I (produced by E. coli serotype 026:H11). Twofold dilutions of the preparations showed significant (p less than 0.01) neutralizing titers of 1:64 to 1:128. No significant neutralization (greater than 20%) of SLT-II (produced by E. coli strain C600 (933W] was noted. The IVIG preparation lost its inhibitory activity when passed through a protein A-Sepharose column, which bound immune globulin, indicating that its neutralizing effect is related to the antibody content. We also examined sera from 30 children without diarrhea or HUS; only one child had neutralizing titers against Shiga toxin (1:64) and SLT-I (1:128). Immune globulin preparations contain anticytotoxin-neutralizing antibodies, a finding that warrants further investigation of the therapeutic role of these preparations in early treatment of children with HUS related to Shiga toxin and SLT-I.


Assuntos
Anticorpos Antibacterianos/administração & dosagem , Citotoxinas/imunologia , Escherichia coli/imunologia , Síndrome Hemolítico-Urêmica/terapia , Imunização Passiva/métodos , Testes de Neutralização , Shigella dysenteriae/imunologia , Adolescente , Criança , Pré-Escolar , Citotoxicidade Imunológica , Diarreia Infantil/terapia , Disenteria Bacilar/terapia , Infecções por Escherichia coli/terapia , Células HeLa/imunologia , Síndrome Hemolítico-Urêmica/imunologia , Humanos , Lactente
15.
Chest ; 93(4): 772-5, 1988 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-3349832

RESUMO

Thirty-six patients with AIDS and culture-proven nontuberculous mycobacteriosis were compared to 20 patients with acquired immunodeficiency syndrome (AIDS) and tuberculosis with regard to clinical signs, symptoms, and diagnostic methods. Patients with nontuberculous mycobacteriosis were more often younger and homosexuals, while patients with tuberculosis were usually Haitian-American or users of intravenous drugs. A majority of patients with tuberculosis presented with fever and weight loss. These symptoms were seen in approximately 50 percent of the patients with nontuberculous mycobacteriosis. A distinct syndrome of dyspnea, chills, hemoptysis, and chest pain was seen in a significant minority of patients with nontuberculous mycobacteriosis. Lymphadenopathy was seen almost exclusively in patients with tuberculosis. Pulmonary sources (expectorated sputum or bronchoscopy specimens) were the most common source of diagnosis in both groups. Patients in both groups in whom the diagnosis was obtained from pulmonary sources frequently had negative chest x-ray films on presentation. Cavitary disease was absent from both groups.


Assuntos
Síndrome da Imunodeficiência Adquirida/complicações , Infecções por Mycobacterium não Tuberculosas/etiologia , Infecções por Mycobacterium/etiologia , Infecções Oportunistas/etiologia , Tuberculose Pulmonar/etiologia , Adulto , Fatores Etários , Broncoscopia , Feminino , Haiti/etnologia , Homossexualidade , Humanos , Masculino , Infecções por Mycobacterium não Tuberculosas/diagnóstico , Fatores de Risco , Escarro/microbiologia , Transtornos Relacionados ao Uso de Substâncias , Tuberculose Pulmonar/diagnóstico , Estados Unidos
16.
Arch Pathol Lab Med ; 110(8): 749-51, 1986 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-3488048

RESUMO

A 29-year-old Haitian man with acquired immunodeficiency syndrome presented with nasal obstruction and epistaxis. A computed tomogram of the head showed thickened nasal and paranasal sinus mucosa. A biopsy specimen of the turbinate disclosed inflammatory tissue containing amoebic trophozoites. The patient was empirically treated with rifampin and ketoconazole. He died four months after biopsy of other complications of acquired immunodeficiency syndrome. At autopsy, the amoebic infection was found only in the paranasal sinuses, a calf nodule, and in an intradermal abscess in the left leg. Pneumocystitis carinii pneumonia, Mycobacterium avium-cellulare in the liver and retroperitoneal lymph nodes, cytomegalovirus infection of the adrenal glands, and Kaposi's sarcoma in the spleen were additionally present. The organism was cultured and studied by electron microscopy, dark-field microscopy, and immunofluorescence.


Assuntos
Síndrome da Imunodeficiência Adquirida/complicações , Amebíase/complicações , Sinusite/complicações , Adulto , Amebíase/patologia , Amebíase/fisiopatologia , Antibacterianos/uso terapêutico , Epistaxe/complicações , Florida , Haiti/etnologia , Humanos , Masculino , Pneumonia por Pneumocystis/complicações , Pneumonia por Pneumocystis/tratamento farmacológico , Sinusite/tratamento farmacológico , Sinusite/patologia , Sinusite/fisiopatologia
17.
Arch Pathol Lab Med ; 110(5): 433-6, 1986 May.
Artigo em Inglês | MEDLINE | ID: mdl-2421690

RESUMO

Using specific antibodies and the peroxidase-antiperoxidase technique, we were able to demonstrate a variety of fungal organisms in smears and sections of formaldehyde-fixed, paraffin-embedded tissue. The procedure is simple, fast, and accurate and may be used as an alternative to, or in conjunction with, cultural methods to identify fungi specifically.


Assuntos
Micoses/diagnóstico , Animais , Fungos/isolamento & purificação , Humanos , Técnicas Imunoenzimáticas , Micoses/imunologia , Micoses/patologia , Coloração e Rotulagem , Baleias , Leveduras/isolamento & purificação
19.
Arch Pathol Lab Med ; 106(3): 112-4, 1982 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-6895835

RESUMO

A 34-year-old woman had wide-spread panniculitis due to a disseminated infection with Mycobacteria avium-intracellulare. The patient had previously received treatment with high dosages of corticosteroids. Suppurative lesions teeming with acid-fast bacilli and without formation of granulomas were found in many organs, including the skin, mediastinum, spleen, liver, and gastrointestinal tract. Both the appearance of disseminated M avium-intracellular infection resembling panniculitis and the involvement of mediastinum have not previously been reported, to our knowledge.


Assuntos
Infecções por Mycobacterium não Tuberculosas/diagnóstico , Infecções por Mycobacterium/diagnóstico , Paniculite Nodular não Supurativa/diagnóstico , Corticosteroides/efeitos adversos , Adulto , Diagnóstico Diferencial , Feminino , Humanos , Terapia de Imunossupressão , Doenças do Mediastino/microbiologia , Doenças do Mediastino/patologia , Infecções por Mycobacterium/patologia , Mycobacterium avium/isolamento & purificação , Micobactérias não Tuberculosas/isolamento & purificação , Dermatopatias Infecciosas/microbiologia , Dermatopatias Infecciosas/patologia
20.
J Infect Dis ; 142(6): 884-91, 1980 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-6257801

RESUMO

Colostral cells have been previously shown to mediate antibody-dependent cellular cytotoxicity (ADCC) to herpes to simplex virus-infected cells. A comparison of colostral cells to matched peripheral blood mononuclear cells has revealed significantly lower ADCC activity, higher antibody requirements, and slower kinetics of colostral cell ADCC against infected cells. Colostral cells failed to mediate natural killer cytotoxicity. Lymphocytes, monocyte macrophages, and polymorphonuclear leukocytes isolated from peripheral blood and incubated with colostrum from virus-immune or nonimmune women markedly inhibited ADCC. Inhibitory activity was found in lipid and aqueous fractions and was due to an effect on leukocytes, not target cells. A partial explanation was inhibition of expression of leukocyte Fc receptors, a prerequisite for ADCC, by acellular colostrum. These results raise questions concerning the potential antiviral activity of colostral cells in vitro.


Assuntos
Citotoxicidade Celular Dependente de Anticorpos , Colostro/imunologia , Citotoxicidade Imunológica , Leucócitos/imunologia , Feminino , Humanos , Gravidez , Receptores Fc/imunologia , Simplexvirus/imunologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA