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1.
Blood Cancer J ; 7(7): e587, 2017 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-28731456

RESUMO

The Ten Eleven Translocation (TET) enzymes have been found to be mutated in both diffuse large B-cell (DLBCL) and peripheral T-cell (PTCL) lymphomas resulting in DNA hypermethylation. Recent studies in embryonal stem cells showed that ascorbic acid (AA) is a cofactor for TET with a binding site at the catalytic domain, and enhances TET activity. We hypothesized that AA could potentially enhance TET activity in lymphoma cells to cause DNA demethylation, reactivate expression of tumor suppressor genes and enhance chemosensitivity. We demonstrate in vitro that AA treatment of DLBCL and PTCL cells using AA concentrations achievable intravenously increased TET activity leading to DNA demethylation. This epigenetic effect is independent of hydrogen peroxide. AA treatment increased the expression of SMAD1, a tumor suppressor gene known to be suppressed by methylation, and increased chemosensitivity of lymphoma cells. Twenty-nine percent (10/34) of unselected lymphoma patients had plasma AA levels that were deficient suggesting an additional clinical mechanism of TET hypofunction. These data indicate that AA has the potential to modify TET function in lymphoma and enhance chemosensitivity. In addition, the AA deficiency seen in some patients may further impair TET function and contribute to resistance. Clinical trials testing intravenous AA with chemotherapy are warranted.


Assuntos
Ácido Ascórbico/farmacologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Linfoma Difuso de Grandes Células B/embriologia , Oxigenases de Função Mista/biossíntese , Proteínas Proto-Oncogênicas/biossíntese , Regulação para Cima/efeitos dos fármacos , Linhagem Celular Tumoral , Humanos , Linfoma Difuso de Grandes Células B/metabolismo , Linfoma Difuso de Grandes Células B/patologia
2.
Ann Oncol ; 27(1): 165-72, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26487586

RESUMO

BACKGROUND: T-cell malignancies are heterogeneous in their clinical presentation and pathology, and have a poor prognosis. New biomarkers are needed to predict prognosis and to provide insights into signal pathways used by these cells. The goal of this study was to evaluate pretreatment serum cytokines in patients with newly diagnosed T-cell neoplasms and correlate with clinical outcome. PATIENTS AND METHODS: We evaluated 30 cytokines in pretreatment serum from 68 untreated patients and 14 normal controls. Significantly elevated cytokines were correlated with patterns of abnormalities, event-free survival (EFS) and overall survival (OS). RESULTS: Our data demonstrated significantly elevated levels (versus controls) of seven cytokines-epidermal growth factor (EGF), IL-6, IL-12, interferon gamma-induced protein (IP)-10, soluble interleukin (sIL)-2Rα, monokine induced by gamma interferon (MIG), and IL-1RA-in all T-cell neoplasms (P < 0.05). In the angioimmunoblastic subset, all seven cytokines except IP-10 and in the peripheral T-cell lymphoma (TCL)-not otherwise specified subset, only IP-10, sIL-2Rα, MIG, and IL-8 were statistically elevated compared with control. Of these, elevated cytokines all but EGF were predictive of an inferior EFS; IL-1RA, sIL-2Rα, and MIG predicted an inferior OS. In a multivariate analysis, sIL-2Rα [hazard ratio (HR) = 3.95; 95% confidence interval (CI) 1.61-8.38] and IL-1RA (HR = 3.28; 95% CI 1.47-7.29) levels remained independent predictors of inferior EFS. TCL cell lines secreted high levels of sIL-2Rα and expressed the IL-2Rα surface receptor. CONCLUSIONS: This report describes the cytokines relevant to prognosis in patients with untreated TCL and provides the rationale to include serum IL-1RA and sIL-2Rα as biomarkers in future trials. Inhibition of these cytokines may also be of therapeutic benefit.


Assuntos
Biomarcadores Tumorais/sangue , Proteína Antagonista do Receptor de Interleucina 1/sangue , Subunidade alfa de Receptor de Interleucina-2/sangue , Linfoma de Células T/sangue , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Linhagem Celular Tumoral , Intervalo Livre de Doença , Feminino , Humanos , Estimativa de Kaplan-Meier , Linfoma de Células T/mortalidade , Masculino , Pessoa de Meia-Idade , Prognóstico , Modelos de Riscos Proporcionais , Estatísticas não Paramétricas , Adulto Jovem
3.
Eur Radiol ; 25(9): 2682-7, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25740803

RESUMO

OBJECTIVES: The Z0011 trial questioned the role of axillary ultrasound (AxUS) in preoperative staging of breast cancer in patients with ≤2 positive sentinel lymph nodes (SLN). The purpose of this study was to correlate the number of abnormal nodes on AxUS with final nodal burden and determine the utility of AxUS with sampling (AxUS + S) in preoperative staging. METHODS: Six hundred and seventy-nine patients underwent pre-operative AxUS. Suspicious nodes were sampled. Negative axillae proceeded to SLN biopsy. The number of abnormal nodes identified on ultrasound and final histology as well as sensitivity and specificity for AxUS + S were calculated. Subgroup analysis was performed on Z0011 eligible patients. RESULTS: Two hundred and ninety-six patients had positive axillary nodes on final histology with 169 detected by AxUS + S (sensitivity 86.2%, specificity 100%, PPV 100 %, NPV 71.9%). Patients with nodal metastases identified by AxUS had a mean burden of 7.3 nodes on histology (1 node on AxUS = 5.2 nodes on histology, 2 nodes on AxUS = 7.5 nodes, >2 nodes = 10.1 nodes). Patients diagnosed on SLNB had a mean burden of 2.2 nodes. CONCLUSION: A single nodal metastasis detected on AxUS + S correlated with a mean of 5.2 nodes on final histology highlighting that AxUS remains essential in guiding appropriate management of the axilla in breast cancer. KEY POINTS: • Axillary ultrasound +/- sampling is an essential technique in preoperative axillary staging. • Axillary ultrasound findings correlate with final histological axillary node disease burden. • Axillary ultrasound can help triage patients who require axillary lymph node dissection. • The role of axillary ultrasound in breast cancer staging continues to evolve.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/patologia , Linfonodos/diagnóstico por imagem , Linfonodos/patologia , Cuidados Pré-Operatórios , Adulto , Idoso , Idoso de 80 Anos ou mais , Axila , Estudos de Coortes , Bases de Dados Factuais , Feminino , Humanos , Metástase Linfática , Pessoa de Meia-Idade , Estudos Retrospectivos , Sensibilidade e Especificidade , Biópsia de Linfonodo Sentinela/métodos , Ultrassonografia , Adulto Jovem
4.
Leukemia ; 28(1): 147-54, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23979523

RESUMO

Protein tyrosine phosphatases such as PTPN6 can be downregulated in various neoplasms. PTPN6 expression by immunohistochemistry in 40 diffuse large B-cell lymphoma (DLBCL) tumors was lost or suppressed in 53% (21/40). To elucidate the molecular mechanisms of PTPN6 suppression, we performed a comprehensive epigenetic analysis of PTPN6 promoter 2 (P2). None of the DLBCL primary tumors (0/37) had PTPN6 hypermethylation on the CpG1 island using methylation-specific PCR, pyrosequencing, and high-resolution melting assays. However, hypermethylation in 57% (21/37) of cases was found in a novel CpG island (CpG2) in P2. PTPN6 gene suppression was reversed by 5-aza-deoxycytidine (5-Aza), a DNA methyltransferase inhibitor, and the histone deacetylase inhibitor (HDACi) LBH589. LBH589 and 5-Aza in combination inhibited DLBCL survival and PTPN6 hypermethylation at CpG2. The role of histone modifications was investigated with a chromatin-immunoprecipitation assay demonstrating that PTPN6 P2 is associated with silencing histone marks H3K27me3 and H3K9me3 in DLBCL cells but not normal B cells. 3-Deazaneplanocin A, a histone methyltransferase inhibitor, decreased the H3K27me3 mark, whereas HDACi LBH589 increased the H3K9Ac mark within P2 resulting in re-expression of PTPN6. These studies have uncovered novel epigenetic mechanisms of PTPN6 suppression and suggest that PTPN6 may be a potential target of epigenetic therapy in DLBCL.


Assuntos
Epigênese Genética , Linfoma Difuso de Grandes Células B/terapia , Fosfoproteínas Fosfatases/antagonistas & inibidores , Sequência de Bases , Imunoprecipitação da Cromatina , Ilhas de CpG , Metilação de DNA , Primers do DNA , Humanos , Linfoma Difuso de Grandes Células B/genética , Linfoma Difuso de Grandes Células B/patologia , Reação em Cadeia da Polimerase , Regiões Promotoras Genéticas
5.
Leukemia ; 26(6): 1356-64, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22116549

RESUMO

Diffuse large B-cell lymphoma (DLBCL) with an activated B-cell (ABC) gene-expression profile has been shown to have a poorer prognosis compared with tumors with a germinal center B-cell type. ABC cell lines have constitutive activation of STAT3; however, the mechanisms regulating STAT3 signaling in lymphoma are unknown. In studies of class-I histone deacetylase (HDAC) expression, we found overexpression of HDAC3 in phospho STAT3-positive DLBCL and the HDAC3 was found to be complexed with STAT3. Inhibition of HDAC activity by panobinostat (LBH589) increased p300-mediated STAT3(Lys685) acetylation with increased nuclear export of STAT3 to the cytoplasm. HDAC inhibition abolished STAT3(Tyr705) phosphorylation with minimal effect on STAT3(Ser727) and JAK2 tyrosine activity. pSTAT3(Tyr705)-positive DLBCLs were more sensitive to HDAC inhibition with LBH589 compared with pSTAT3(Tyr705)-negative DLBCLs. This cytotoxicity was associated with downregulation of the direct STAT3 target Mcl-1. HDAC3 knockdown upregulated STAT3(Lys685) acetylation but prevented STAT3(Tyr705) phosphorylation and inhibited survival of pSTAT3-positive DLBCL cells. These studies provide the rationale for targeting STAT3-positive DLBCL tumors with HDAC inhibitors.


Assuntos
Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Histona Desacetilases/metabolismo , Linfoma Difuso de Grandes Células B/genética , Linfoma Difuso de Grandes Células B/metabolismo , Fator de Transcrição STAT3/genética , Acetilação , Western Blotting , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/metabolismo , Proliferação de Células/efeitos dos fármacos , Citoplasma/efeitos dos fármacos , Citoplasma/metabolismo , Imunofluorescência , Inibidores de Histona Desacetilases/farmacologia , Humanos , Ácidos Hidroxâmicos/farmacologia , Técnicas Imunoenzimáticas , Imunoprecipitação , Indóis , Linfoma Difuso de Grandes Células B/patologia , Panobinostat , Fosforilação/efeitos dos fármacos , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais/efeitos dos fármacos , Células Tumorais Cultivadas , Tirosina/metabolismo
6.
Vet Parasitol ; 184(1): 48-58, 2012 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-21880430

RESUMO

Haemonchosis is considered to be the most economically important gastrointestinal disease of small ruminants in the tropics and subtropics. However, chemical anthelmintics, which were the mainstay of control, have been compromised by a high prevalence of resistance worldwide. Copper oxide wire particles (COWP) have been shown to have anthelmintic effects, but few studies have examined their use under field conditions. The use of COWP was therefore evaluated as a tactical anthelmintic treatment in indigenous goats raised under communal farming conditions in Bergville, KwaZulu-Natal Province, South Africa. At the beginning of the summer rainfall season (October 2007), the faecal egg counts of 172 female goats belonging to 15 farmers were determined and this sampling continued every four weeks until the second week of January 2008. The goats within each of the 15 herds were ranked according to their faecal egg counts for this week. The goats were sequentially paired off within each ranking starting with those goats with the highest counts. One goat from each pair was randomly allocated to a treated or control group. Two weeks later, a 4 g COWP bolus was randomly administered to each goat in the treated group. Faecal egg counts were carried out on the goats two weeks following treatment, and the sampling of the goats then proceeded every four weeks until October 2008. Except for the six-week period prior to the administration of the COWP, the goats were examined according to the FAMACHA(©) system and symptomatically treated with 12 mg/kg levamisole when anaemic. The percentage reduction in faecal egg count due to the COWP treatment was 89.0%. Mean pre- and post-treatment faecal egg counts for the COWP-treated group (n=73) were 2347 eggs per gram of faeces (epg) and 264 epg, respectively. The corresponding values for the untreated controls (n=66) were 2652 epg and 2709 epg. The prevalence of Haemonchus spp. larvae in pre- and post-treatment faecal cultures was 72% and 46%, respectively. Symptomatic anthelmintic treatments in combination with mid-summer tactical treatments with COWP appear to be useful strategies for the control of Haemonchus contortus in indigenous goats in this farming system and this approach could have application in other similar agro-ecological zones.


Assuntos
Anti-Helmínticos/uso terapêutico , Cobre/uso terapêutico , Doenças das Cabras/tratamento farmacológico , Hemoncose/veterinária , Levamisol/uso terapêutico , Análise de Variância , Animais , Constituição Corporal , Peso Corporal , Fezes/parasitologia , Feminino , Cabras , Hemoncose/tratamento farmacológico , Haemonchus/fisiologia , Hematócrito , Contagem de Ovos de Parasitas/veterinária , Chuva , África do Sul , Temperatura , Resultado do Tratamento
7.
Leukemia ; 26(2): 340-8, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21826062

RESUMO

Notch-stimulated signaling cascade results in transcriptional regulation of genes involved in cell fate decision, apoptosis and proliferation and has been implicated in various malignancies. Here, we investigated the impact of MRK003, an inhibitor of this pathway, on myeloma and lymphoma cells. We first studied the expression patterns of notch receptors and ligands on multiple myeloma (MM) and non-Hodgkin's lymphoma (NHL) cell lines. Next, we used a γ-secretase inhibitor, MRK003 to test the importance of notch-stimulated pathways in MM and NHL disease biology. We observed expression of notch receptors and ligands on MM and NHL cell lines. MRK003 treatment induced caspase-dependent apoptosis and inhibited proliferation of MM and NHL cell lines and patient cells. Examination of signaling events after treatment showed time-dependent decrease in levels of the notch intracellular domain, Hes1 and c-Myc. MRK003 downregulated cyclin D1, Bcl-Xl and Xiap levels in NHL cells and p21, Bcl-2 and Bcl-Xl in MM cells. In addition, MRK003 caused an upregulation of pAkt, indicating crosstalk with the PI3K/Akt pathway. We evaluated MRK003 in combination with Akt1/2 kinase inhibitor and observed synergy in killing MM and NHL cell lines examined.


Assuntos
Secretases da Proteína Precursora do Amiloide/antagonistas & inibidores , Óxidos S-Cíclicos/farmacologia , Inibidores Enzimáticos/farmacologia , Linfoma não Hodgkin/tratamento farmacológico , Mieloma Múltiplo/tratamento farmacológico , Tiadiazóis/farmacologia , Apoptose/efeitos dos fármacos , Sequência de Bases , Linhagem Celular Tumoral , Óxidos S-Cíclicos/uso terapêutico , Primers do DNA , Ensaios de Seleção de Medicamentos Antitumorais , Inibidores Enzimáticos/uso terapêutico , Humanos , Linfoma não Hodgkin/patologia , Mieloma Múltiplo/patologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Tiadiazóis/uso terapêutico
8.
Onderstepoort J Vet Res ; 75(3): 237-47, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19040138

RESUMO

The potential economic benefits of combining tactical anthelmintic treatment for gastrointestinal nematodes and nutritional supplementation with urea-molasses blocks were examined in Boer goats raised under extensive grazing conditions in the summer rainfall area of South Africa. Eight groups of nine goats were monitored over a 12-month period from 1 October 2002 to 9 October 2003. Ad libitum nutritional supplementation with urea-molasses blocks was provided when the goats were housed at night, during the summer (wet season--December 2002 to February 2003), and/or the winter (dry season--June 2003 to August 2003). All the goats were treated symptomatically for Haemonchus contortus infection when deemed necessary by clinical examination of the conjunctiva for anaemia using the FAMACHA system. Half the groups were tactically treated for gastrointestinal nematodes in mid-summer (28 January 2003). Under the symptomatic treatment, climatic and extensive grazing conditions encountered during the trial, feed supplementation in the winter dry season had the greatest economic benefit and is therefore recommended. Tactical anthelmintic treatment afforded no additional advantage, but the nematode challenge was low.


Assuntos
Criação de Animais Domésticos/métodos , Anti-Helmínticos/uso terapêutico , Doenças das Cabras/tratamento farmacológico , Helmintíase Animal/tratamento farmacológico , Melaço , Ureia/administração & dosagem , Anemia/prevenção & controle , Anemia/veterinária , Ração Animal , Fenômenos Fisiológicos da Nutrição Animal , Animais , Anti-Helmínticos/economia , Análise Custo-Benefício , Suplementos Nutricionais , Feminino , Doenças das Cabras/economia , Doenças das Cabras/prevenção & controle , Cabras , Helmintíase Animal/economia , Helmintíase Animal/prevenção & controle , Masculino , Poaceae , Estações do Ano , África do Sul , Resultado do Tratamento
9.
J S Afr Vet Assoc ; 78(2): 81-9, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17941600

RESUMO

This study was carried out with the cooperation of farmers owning communally grazed indigenous goats in southwestern KwaZulu-Natal Province, South Africa, where farmers had identified poor reproductive performance in their herds as one of their major problems. The aim was to quantify the effects of 3 interventions and the interaction between these interventions on goat productivity and gastrointestinal nematode infection. The interventions were: urea-molasses block supplementation during the dry winter seasons of 2004 and 2005, tactical anthelmintic treatment with ivermectin (400 microg/kg) during the wet summer period (on 3 January 2005) and symptomatic treatment with ivermectin (400 microg/kg) of all goats judged anaemic throughout the entire study period. The FAMACHA system was used as a gauge of anaemia. It was noted that goats considered anaemic tended to remain so throughout the study period. The tactical anthelmintic treatment was effective as it markedly reduced (P = 0.066) the summer peak in faecal egg counts and is therefore recommended. By contrast, while the urea-molasses block supplementation appeared to reduce the faecal egg counts immediately following the 2004 supplementation (P < 0.05), this did not hold true in 2005. Interestingly, in the tactically treated anaemic goats, the improvement in the number of kids suckled per doe year-on-year tended to be greater than in the non-anaemic goats. It is considered that the routine symptomatic treatment of anaemic goats may have been a key factor. More detailed investigations into the routine symptomatic treatment of anaemic goats are therefore recommended.


Assuntos
Anti-Helmínticos/uso terapêutico , Doenças das Cabras/prevenção & controle , Cabras/fisiologia , Helmintíase Animal/prevenção & controle , Ivermectina/uso terapêutico , Melaço , Ureia/administração & dosagem , Anemia/prevenção & controle , Anemia/veterinária , Ração Animal , Fenômenos Fisiológicos da Nutrição Animal , Animais , Suplementos Nutricionais , Fezes/parasitologia , Feminino , Doenças das Cabras/epidemiologia , Helmintíase Animal/epidemiologia , Masculino , Contagem de Ovos de Parasitas/veterinária , Estações do Ano , África do Sul/epidemiologia , Aumento de Peso
10.
J Clin Oncol ; 19(3): 720-6, 2001 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-11157023

RESUMO

PURPOSE: Previous studies in patients with non-Hodgkin's lymphoma (NHL) and other malignancies have suggested that the presence of host infiltrates in the tumors of these patients may predict a better outcome. This study was undertaken to determine the prognostic importance of the presence of T cells in the biopsy specimens of patients with B-cell NHL. PATIENTS AND METHODS: Seventy-two patients with diffuse large B-cell NHL were prospectively evaluated at a single institution between 1987 and 1994. The percentage of CD3+, CD3+/HLA-DR+, CD4+, CD8+, and natural killer cells was determined by flow cytometry in the pretreatment diagnostic biopsy specimen and correlated with patient outcome. RESULTS: An increase in the percentage CD4+ T cells in the pretreatment tumor biopsies significantly correlated with patient outcome. The percent of CD4+ T cells was also highly correlated with CD3+/HLA-DR+, CD45RO+, and low L-selectin (CD62L) expression, indicating that the CD4+ T cells are activated memory T-helper cells. Those patients with increased numbers of CD4+ T cells, compared with other patients, had a significantly longer 5-year failure-free survival (72% v 43%, respectively; P =.04), as well as a significantly longer 5-year overall survival (65% v 38%, respectively; P =.05). When evaluated in a multivariate model, the International Prognostic Index and more than 20% infiltrating CD4+ T cells in the pretreatment biopsy were significant independent predictors of relapse-free and overall survival. CONCLUSION: The presence of increased numbers of activated CD4+ cells in the area of B-cell diffuse large-cell NHL predicts a better prognosis. This finding provides a strong rationale for the investigation of cellular immunotherapy in B-cell NHL.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Linfoma de Células B/imunologia , Linfoma Difuso de Grandes Células B/imunologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Biópsia , Intervalo Livre de Doença , Feminino , Citometria de Fluxo , Humanos , Imunofenotipagem , Ativação Linfocitária/imunologia , Linfócitos do Interstício Tumoral/imunologia , Linfoma de Células B/tratamento farmacológico , Linfoma de Células B/patologia , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Linfoma Difuso de Grandes Células B/patologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
11.
Arthritis Res ; 3(1): 41-7, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11178125

RESUMO

The present study demonstrates that endogenous production of IL-12 is crucial for survival in Staphylococcus aureus-induced arthritis in mice. Staphylococcal load is enhanced in several organs, because of lack of IL-12. This might be due to decreased production of IFN-gamma in IL-12-deficient mice. Although IL-12-deficient mice were exposed to higher staphylococcal load, they demonstrated no increased severity of arthritis as compared with control animals.


Assuntos
Artrite Infecciosa/imunologia , Artrite Infecciosa/microbiologia , Interleucina-12/fisiologia , Sepse/imunologia , Infecções Estafilocócicas/imunologia , Animais , Artrite Infecciosa/sangue , Contagem de Colônia Microbiana , Interferon gama/biossíntese , Interferon gama/sangue , Interleucina-12/biossíntese , Interleucina-12/deficiência , Interleucina-12/genética , Articulações/microbiologia , Rim/microbiologia , Fígado/microbiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Sepse/microbiologia , Staphylococcus aureus/imunologia
12.
Br J Haematol ; 115(4): 854-61, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11843819

RESUMO

Recent reports suggest that the expression of germline (GL) Ig variable region heavy-chain genes (VH) is a negative prognostic factor for B-cell chronic lymphocytic leukaemia (B-CLL) patients and that CLL B-cell CD38 expression may be a surrogate marker of Ig VH gene status. Currently, however, the usefulness of this surrogate marker is controversial. Therefore, our goal was to study the ability of CD38 to act as a surrogate marker for Ig VH somatic mutation (SM), and to identify differences in overall survival (OS), progression-free survival (PFS) and response in B-CLL patients based on these two markers. We first assessed the relationship between CD38 expression and Ig VH status on 131 B-CLL patients, including 66 patients enrolled in three North Central Cancer Treatment Group Trials. Although the mean percentages of CD38+ clonal B cells were significantly higher for patients classified as GL versus SM, CD38 was not a reliable marker for clonal B-cell SM. Overall, GL patients exhibited significantly shorter OS and PFS times than SM patients. Despite the inability of clonal B-cell CD38 expression to predict Ig VH mutation status, patients with < or =30% CD38+ cells did have shorter PFS and OS times than did CLL patients with < 30% CD38+ cells. Thus, the relationship between CD38 expression and Ig VH mutation status in B-CLL is not straightforward. Nevertheless, analysis in a co-operative group clinical trial setting suggests that both B-cell markers alone or in combination may have clinical usefulness. These data strongly encourage the study of these biological markers as they relate to disease heterogeneity in B-CLL.


Assuntos
Antígenos CD , Antígenos de Diferenciação/análise , Linfócitos B/imunologia , Genes de Imunoglobulinas , Leucemia Linfocítica Crônica de Células B/imunologia , NAD+ Nucleosidase/análise , ADP-Ribosil Ciclase , ADP-Ribosil Ciclase 1 , Biomarcadores/análise , Progressão da Doença , Intervalo Livre de Doença , Marcadores Genéticos , Humanos , Leucemia Linfocítica Crônica de Células B/genética , Glicoproteínas de Membrana , Modelos de Riscos Proporcionais , Risco , Hipermutação Somática de Imunoglobulina , Estatísticas não Paramétricas , Taxa de Sobrevida
13.
Infect Immun ; 68(5): 2431-4, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10768927

RESUMO

To investigate the role of B cells in experimental, superantigen-mediated Staphylococcus aureus arthritis and sepsis, we used gene-targeted B-cell-deficient mice. The mice were inoculated intravenously with a toxic shock syndrome toxin 1 (TSST-1)-producing S. aureus strain. The B-cell-deficient and thus agamma-globulinemic mice showed striking similarities to the wild-type control animals with respect to the development of arthritis, the mortality rate, and the rate of bacterial clearance. Surprisingly, we found that the levels of gamma interferon in serum were significantly lower (P < 0. 0001) in B-cell-deficient mice than in the controls, possibly due to impaired superantigen presentation and a diminished expression of costimulatory molecules. In contrast, the levels of interleukin-4 (IL-4), IL-6, and IL-10 in serum were equal in both groups. Our findings demonstrate that neither mature B cells nor their products significantly contribute to the course of S. aureus-induced septic arthritis.


Assuntos
Artrite Infecciosa/imunologia , Linfócitos B/imunologia , Infecções Estafilocócicas/imunologia , Animais , Artrite Infecciosa/microbiologia , Artrite Infecciosa/patologia , Artrite Infecciosa/fisiopatologia , Modelos Animais de Doenças , Feminino , Interferon gama/biossíntese , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Sepse/imunologia , Sepse/microbiologia , Sepse/patologia , Sepse/fisiopatologia , Infecções Estafilocócicas/microbiologia , Infecções Estafilocócicas/patologia , Infecções Estafilocócicas/fisiopatologia , Staphylococcus aureus/imunologia
14.
Clin Cancer Res ; 6(2): 681-92, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10690554

RESUMO

Phenylacetate (PA) and phenylbutyrate (PB) are aromatic fatty acids that are presently undergoing evaluation as potential antineoplastic agents. In vitro, PA and PB cause differentiation or growth inhibition of malignant cells. Clinical trials of these drugs as single agents indicate that they are not myelosuppressive; therefore, combinations with other chemotherapy agents may be possible. The goals of this study were to determine whether PA and PB (a) are cytotoxic to malignant B cells from patients with non-Hodgkin's lymphoma and B-cell chronic lymphocytic leukemia and (b) exhibit additive or synergistic induction of apoptosis when administered to myeloma cell lines in combination with conventional drugs. In the clinical specimens, cytotoxicity was measured by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, and percent apoptosis was measured using 7-aminoactinomycin D and flow cytometry. Viability was decreased by > 50% in 7% (1/15) of non-Hodgkin's lymphoma samples treated with 5 mM PA, 27% treated with 1 mM PB, and 60% treated with 2 mM PB. Likewise, viability was decreased by > 50% in 44% (4/9) of chronic lymphocytic leukemia samples treated with 5 mM PA, 67% treated with 1 mM PB, and 100% treated with 2 mM PB. Studies in the myeloma cell lines demonstrated that PB treatment induced activation of caspases 3, 7, and 9 accompanied by cleavage of their substrates and internucleosomal DNA degradation. Combinations of PA or PB with conventional drugs (cytarabine, topotecan, doxorubicin, etoposide, chlorambucil, melphalan, fludarabine, carboplatin, and cisplatin) were examined for synergism (combination index < 1 in median effect analysis) in inducing apoptosis of both the MY5 and 8226 human myeloma cell lines. At concentrations that killed > 50% of cells, most combinations were additive; however, PB was synergistic with cytarabine, etoposide, and topotecan, with the combination index < 1 at each of the 50, 75, and 95% apoptosis levels. These observations indicate that PA and PB can induce apoptosis in malignant B cells and enhance the cytotoxicity of agents used in the treatment of these malignancies.


Assuntos
Antineoplásicos/toxicidade , Apoptose/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Fenilacetatos/toxicidade , Fenilbutiratos/toxicidade , Interações Medicamentosas , Sinergismo Farmacológico , Humanos , Leucemia Linfocítica Crônica de Células B , Linfoma de Células B , Linfoma não Hodgkin , Mieloma Múltiplo , Células Tumorais Cultivadas
15.
Leuk Lymphoma ; 34(5-6): 529-37, 1999 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10492076

RESUMO

The reasons for differences in outcome between groups of patients with diffuse large cell lymphoma (DLCL) defined by clinical prognostic factors are largely unknown. Measures of cell proliferation may offer a biological explanation for these differences. This study tested the hypothesis that these survival differences between the groups defined by established prognostic factors were due to the proliferative index. The bromodeoxyuridine labeling index (LI), a measure of the S-phase fraction, was prospectively determined on fresh tumor specimens obtained at initial diagnosis in 80 patients with DLCL seen between 1986-1993 at a single institution. Patients were grouped using prognostic factors that were significant in a univariate analysis as well as the International Index (IPI). The LI in each of these groups was compared to determine whether the differences in outcome between the groups could be explained by differences in the LI. The median LI for all patients was 5.1% (range: 0.1-25%). When the predictive effect of the LI on response and survival was analyzed, the LI did not correlate with complete response or disease-free survival (DFS). There was a trend, however, for patients with a lower LI to have a poorer overall survival (p=0.06). When the patients were analyzed using the International Index (IPI), the mean LI for patients in the low-risk, low-intermediate, high-intermediate and high risk groups was 7.1%, 10.0%, 6.4% and 6.6% respectively (p=0.41). When analyzed separately, there was no significant difference in the LI for any of the patient groups defined by significant prognostic factors. The only difference in the LI was that the median LI in patients with T-cell DLCL was significantly lower than the LI in patients with B-cell DLCL (p=0.001) and these patients had an inferior complete response rate (p=0.001), disease-free survival (p=0.003) and overall survival (p=0.015). In this study, the LI, a measure of lymphoma cell proliferation, was not a significant prognostic factor for response, disease-free survival or overall survival. Furthermore, the LI did not explain the differences in outcome between patient groups defined by the IPI. However, a lower LI seen in patients with T-cell DLCL may account for their poorer response to therapy and inferior survival when compared to patients with B-cell DLCL.


Assuntos
Linfoma Difuso de Grandes Células B/mortalidade , Linfoma Difuso de Grandes Células B/patologia , Índice Mitótico , Índice de Gravidade de Doença , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Intervalo Livre de Doença , Feminino , Humanos , L-Lactato Desidrogenase/sangue , Linfoma de Células B/sangue , Linfoma de Células B/diagnóstico , Linfoma de Células B/mortalidade , Linfoma de Células B/patologia , Linfoma de Células B/terapia , Linfoma Difuso de Grandes Células B/sangue , Linfoma Difuso de Grandes Células B/diagnóstico , Linfoma Difuso de Grandes Células B/terapia , Linfoma de Células T/sangue , Linfoma de Células T/diagnóstico , Linfoma de Células T/mortalidade , Linfoma de Células T/patologia , Linfoma de Células T/terapia , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Prognóstico , Recidiva , Indução de Remissão , Taxa de Sobrevida
16.
Onderstepoort J Vet Res ; 66(4): 273-84, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10689700

RESUMO

Surveys to determine the prevalence and degree of resistance of Haemonchus spp. of sheep and goats to the available anthelmintics in South Africa indicate that small ruminant production is entering a crisis situation. Three surveys employing the faecal egg count reduction (FECR) test to determine resistance were conducted in some of the main sheep-producing areas in the summer rainfall region of South Africa, where H. contortus is the principal worm species in sheep. After analyzing the data recorded in the surveys by six different methods, including the RESO test at two different levels of confidence, the results obtained in the least stringent one (geometric mean reduction of the worm egg counts of drenched, vs untreated group of sheep) are reported in this paper, so that if any bias was obtained it would be in the favour of the anthelmintic. In Mpumalanga and KwaZulu-Natal there was anthelmintic resistance in Haemonchus spp. on all the 52 farms surveyed. Sixteen percent of the strains of H. contortus were < 60% susceptible to three of the four anthelmintics tested, and 8% of the strains were < 40% susceptible to all four of the anthelmintics. FECR tests of sheep in six localities in the Lebowa district of Northern Province indicated that even in previously disadvantaged communities where anthelmintic treatment is less intensive, anthelmintic resistance is developing, and is possibly at the level at which the situation on commercial sheep and goat farms in South Africa was 25 years ago. From the data it appears that the level of anthelmintic resistance of H. contortus in South Africa is possibly the highest that has so far been recorded in the world and that strains of it are emerging that may soon not be controllable by treatment with any of the existing anthelmintics. Farmers in the summer rainfall region, if not the whole country, must be alerted to the immediate need for testing the parasite burdens of their sheep for susceptibility to preparations in all four groups of anthelmintic compounds currently available. Alternative methods of integrated worm control, including biological, must be sought and implemented with urgency, to reduce further selection for resistance and to induce reversion of the resistance that has already developed.


Assuntos
Anti-Helmínticos/uso terapêutico , Doenças das Cabras/tratamento farmacológico , Hemoncose/veterinária , Haemonchus/efeitos dos fármacos , Doenças dos Ovinos/tratamento farmacológico , Albendazol/farmacologia , Albendazol/uso terapêutico , Animais , Anti-Helmínticos/farmacologia , Resistência a Medicamentos , Fezes/parasitologia , Doenças das Cabras/parasitologia , Cabras , Hemoncose/tratamento farmacológico , Ivermectina/farmacologia , Ivermectina/uso terapêutico , Levamisol/farmacologia , Levamisol/uso terapêutico , Contagem de Ovos de Parasitas , Rafoxanida/farmacologia , Rafoxanida/uso terapêutico , Distribuição Aleatória , Ovinos , Doenças dos Ovinos/parasitologia , África do Sul
17.
Leuk Lymphoma ; 31(1-2): 167-75, 1998 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9720726

RESUMO

Syndecan-1 is a low-affinity receptor for basic fibroblast growth factor (bFGF). In this study, we used flow cytometry to examine expression of syndecan-1 on monoclonal cells from the blood (n = 37) and marrow (n = 81) of patients with plasma cell (PC) proliferative disorders (PCPD) and blood cells from patients (n = 39) with B cell chronic lymphocytic leukemia (B-CLL). The marrow CD38+CD45- and CD38+CD45+ PC were syndecan-1 positive in all patients with PCPD and there was no difference between patients with monoclonal gammopathy of undetermined significance (MGUS) vs multiple myeloma or cases with vs without bone lesions. In 38% of cases, syndecan-1 expression on the PC was heterogeneous with > or =25% of PC syndecan-1 negative. We found similar syndecan-1 expression on blood and marrow PC in the 36 cases with paired samples. CLL cells were syndecan-1 negative in 97% (38/39) of the cases. Syndecan-1 is a useful marker to detect malignant plasma cells in the blood or marrow; however, it is not helpful in distinguishing MGUS from active myeloma. In addition, syndecan-1 is present on the less mature (CD45+) PC, and there is heterogeneity of expression within and between patients. The relevance of the bFGF bound to myeloma cells via syndecan-1 remains to be elucidated.


Assuntos
Leucemia Linfocítica Crônica de Células B/metabolismo , Glicoproteínas de Membrana/metabolismo , Mieloma Múltiplo/metabolismo , Paraproteinemias/metabolismo , Proteoglicanas/metabolismo , Divisão Celular/fisiologia , Eritrócitos/efeitos dos fármacos , Humanos , Estudos Retrospectivos , Sindecana-1 , Sindecanas
19.
Commun Dis Rep CDR Rev ; 7(6): R87-90, 1997 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-9185382

RESUMO

Preliminary enquiries following prompt notification of three cases of suspected food poisoning revealed that they had all attended the same three functions during the preceding weekend. Subsequent investigation identified 49 people with gastrointestinal symptoms, 13 of whom were infected with Salmonella enteritidis phage type 6. Forty-five of those with symptoms, including 11 with confirmed infection, had eaten a buffet meal at a public house. Eating egg sandwiches was strongly associated with infection. Defects in the kitchen structure and the storage and handling of the implicated food items provided the potential for cross contamination. Salmonella was isolated from several environmental sites, including a general purpose cleaning cloth. Two different quiches and pork pies, which were possible vehicles of infection were thought to have been contaminated after being brought into the kitchen. The investigation did not reveal whether or not shell eggs used in the sandwiches were the original source or whether they too had been contaminated during their preparation.


Assuntos
Infecções por Salmonella/diagnóstico , Salmonella enteritidis , Surtos de Doenças , Microbiologia de Alimentos , Humanos , Infecções por Salmonella/epidemiologia
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