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2.
Eur Rev Med Pharmacol Sci ; 21(6): 1329-1334, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-28387894

RESUMO

OBJECTIVE: According to the JNC7 report, prehypertension category includes subjects with systolic blood pressure between 120 and 139 mmHg and/or diastolic blood pressure between 80 and 89 mmHg that would be at risk for developing hypertension and its untoward sequelae as myocardial infarction and cerebrovascular disease. Moreover, ambulatory blood pressure monitoring made it possible to detect subjects with masked hypertension, who are at risk of greater target organ damage than those with normal ambulatory or home blood pressure. The aim of this study was to evaluate the risk of cardiac, cerebral and vascular events in a group of prehypertensive subjects, with and without masked hypertension. PATIENTS AND METHODS: We studied 204 consecutive asymptomatic prehypertensive subjects without history and signs of cardiovascular disease or diabetes. All the subjects underwent clinical evaluation, electrocardiogram, routine laboratory tests and ambulatory blood pressure monitoring. They were followed-up for a maximum of 237 months or until a cardiovascular event occurred. RESULTS: Twenty-seven cardiovascular events (13.2%) occurred, including 4 abdominal aortic aneurysms. Age (p<0.0001), total cholesterol (p=0.004), smoking (p=0.03) and clinically overt hypertension development (p=0.011) were related to cardiovascular events. Prognosis was not related to masked hypertension. CONCLUSIONS: The results of this study suggest that, in subjects with prehypertension, followed for 20 years, traditional cardiovascular risk factors and development of clinically overt hypertension could be more relevant than ambulatory hypertension in the prediction of an adverse outcome.


Assuntos
Pré-Hipertensão/epidemiologia , Adulto , Idoso , Pressão Sanguínea , Monitorização Ambulatorial da Pressão Arterial , Doenças Cardiovasculares/epidemiologia , Feminino , Seguimentos , Humanos , Hipertensão/epidemiologia , Masculino , Pessoa de Meia-Idade , Fatores de Risco
3.
J Fr Ophtalmol ; 38(6): 486-92, 2015 Jun.
Artigo em Francês | MEDLINE | ID: mdl-25976135

RESUMO

PURPOSE: The useful field of view is a test which takes into account the influence of patient attention during the evaluation of the visual field. This study aims to generate normative data for an adaptation of the useful field of view (UFOV) test. These normative data are essential to judge, in a clinical setting, whether patients' performance is normal or not across demographically similar peers, in order to advise whether or not to resume driving after a brain injury (traumatic brain injury, stroke or cerebral tumour). PATIENTS AND METHODS: This study examined demographic influences on an UFOV adaptation in a sample of 52 control participants (17 males and 35 females, aged 19 to 69) with no prior ophthalmologic or neurologic history. This adaptation used three visual attention tasks. In a simple task (ST), the participant had to detect, as fast as (s)he could, a single target in a visual display; in a double task (DT,) (s)he had to detect both a central and a lateral target in a double task with visual distractions present on the screen. The number of missed targets and the time needed to detect them are measured. RESULTS: Time to detect target was found to differ by gender and by age. Men and young people (from 19 to 29 years) are faster at detecting central and lateral targets. However, no demographic influence was observed on the number of missed targets. CONCLUSIONS: A normative table for this French UFOV adaptation is provided. This will allow clinicians to compare patient performance with similar peers and may help in identifying persons who would benefit from training on a driving simulator or having a road test with a driving-school.


Assuntos
Atenção , Campos Visuais , Adulto , Fatores Etários , Idoso , Condução de Veículo/psicologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reconhecimento Visual de Modelos , Tempo de Reação , Valores de Referência , Fatores Sexuais , Adulto Jovem
4.
Oncogene ; 30(13): 1551-65, 2011 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-21170086

RESUMO

Release from growth factor dependence and acquisition of signalling pathway addiction are critical steps in oncogenesis. To identify genes required on mammalian target of rapamycin (mTOR) addiction, we performed a genome-wide short hairpin RNA screen on a v-H-ras-transformed Pten-deficient cell line that displayed two alternative growth modes, interleukin (IL)-3-independent/mTOR-addicted proliferation (transformed growth mode) and IL-3-dependent/mTOR-non-addicted proliferation (normal growth mode). We screened for genes required only in the absence of IL-3 and thus specifically for the transformed growth mode. The top 800 hits from this conditional lethal screen were analyzed in silico and 235 hits were subsequently rescreened in two additional Pten-deficient cell lines to generate a core set of 47 genes. Hits included genes encoding mTOR and the mTOR complex 2 (mTORC2) component rictor and several genes encoding mitochondrial functions including components of the respiratory chain, adenosine triphosphate synthase, the mitochondrial ribosome and mitochondrial fission factor. Small interfering RNA knockdown against a sizeable fraction of these genes triggered apoptosis in human cancer cell lines but not in normal fibroblasts. We conclude that mTORC2-addicted cells require mitochondrial functions that may be novel drug targets in human cancer.


Assuntos
Mitocôndrias/fisiologia , Interferência de RNA , RNA Interferente Pequeno/genética , Serina-Treonina Quinases TOR/fisiologia , Transativadores/fisiologia , Trifosfato de Adenosina/biossíntese , Animais , Linhagem Celular Tumoral , Proliferação de Células , Glucose/metabolismo , Humanos , Interleucina-3/farmacologia , Camundongos , Transdução de Sinais
6.
Ann Rheum Dis ; 69(1): 132-7, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19158115

RESUMO

OBJECTIVES: To assess subclinical central nervous system (CNS) involvement in primary Sjögren syndrome (pSS), by comparing standard brain MRI, in-depth neuropsychological testing and (99m)Tc-ECD brain single-photon emission computed tomography (SPECT) of patients with pSS with matched controls. METHODS: 10 women (<55 years old), with pSS defined using European-American criteria, presence of anti-SSA and/or anti-SSB antibodies and no history of neurological involvement were prospectively investigated, and compared with 10 age- and sex-matched controls. All subjects underwent, within 1 month, brain MRI, neuropsychological testing, including overall evaluation and focal cognitive function assessment, and (99m)Tc-ECD brain SPECT. RESULTS: (99m)Tc-ECD brain SPECT abnormalities were significantly more common in patients with pSS (10/10) than controls (2/10; p<0.05). Cognitive dysfunctions, mainly expressed as executive and visuospatial disorders, were also significantly more common in patients with pSS (8/10) than controls (0/10; p<0.01). Notably, between-group comparisons enabled a significant correlation to be established between neuropsychological assessment and (99m)Tc-ECD brain SPECT abnormalities in patients with pSS (r(s) = 0.49, p<0.01). MRI abnormalities in patients and controls did not differ significantly. CONCLUSIONS: Neuropsychological testing and (99m)Tc-ECD brain SPECT seem to be the most sensitive tools to detect subclinical CNS dysfunction in pSS. The strong correlation between cortical hypoperfusion in (99m)Tc-ECD brain SPECT and cognitive dysfunction suggests an organic aetiology of CNS dysfunction in pSS. These data should be confirmed in a larger study.


Assuntos
Encéfalo/diagnóstico por imagem , Transtornos Cognitivos/etiologia , Síndrome de Sjogren/psicologia , Adolescente , Adulto , Estudos de Casos e Controles , Transtornos Cognitivos/diagnóstico por imagem , Cisteína/análogos & derivados , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Pessoa de Meia-Idade , Testes Neuropsicológicos , Compostos de Organotecnécio , Compostos Radiofarmacêuticos , Síndrome de Sjogren/diagnóstico por imagem , Tomografia Computadorizada de Emissão de Fóton Único/métodos
7.
Bone Marrow Transplant ; 45(6): 1052-5, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19855442

RESUMO

EBV-associated post transplant lymphoproliferative disease (EBV-PTLD) is a life-threatening complication that may occur after hemopoietic SCT. We prospectively screened 80 children on a weekly basis using nested quantitative PCR to evaluate EBV genome copies. EBV viral load <1000 copies per 10(5) PBMC was observed in 63% of transplants, whereas it was between 1000 and 9999 copies per 10(5) PBMC in 13%, and between 10 000 and 19 999 in 10%, with no significant increase in percentage of CD20+ lymphocytes. Viral load reached > or = 20 000 copies per 10(5) PBMC in 14% of patients, and rituximab was administered to 75% of them. None of the patients except one developed a lymphoproliferative disease. Our study found that only 13% of unrelated donor HSCT recipients had a very high risk of EBV-PTLD defined as > or = 20 000 geq per 10(5) PBMC associated with an increase in CD20+ lymphocyte. We suggest that rituximab could be administered in the presence of very high levels of EBV-DNA viral load or in the presence of mid levels of EBV-DNA viral load associated with an increase in the percentage of CD20+ lymphocytes. Through this approach, we significantly reduced the number of patients treated with rituximab, and consequently the acute and chronic adverse events related to this treatment.


Assuntos
Linfócitos B/patologia , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Herpesvirus Humano 4/fisiologia , Carga Viral , Ativação Viral , Anticorpos Monoclonais/uso terapêutico , Anticorpos Monoclonais Murinos , Antígenos CD20 , Criança , Pré-Escolar , DNA Viral/sangue , Feminino , Humanos , Contagem de Linfócitos , Transtornos Linfoproliferativos/etiologia , Transtornos Linfoproliferativos/prevenção & controle , Masculino , Estudos Prospectivos , Rituximab , Transplante Homólogo
8.
Bone Marrow Transplant ; 41 Suppl 2: S100-3, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18545229

RESUMO

Viral infections are a rare complication in autologous hemopoietic stem cell transplant (HSCT) recipients but represent a frequent cause of disease after allogeneic HSCT. In the last years, there has been an increase in the number of viral diseases observed in these patients. This fact may be at least partially due to an improvement in diagnostic facilities, but the increasing number of transplant procedures and the more severe immunosuppression may also have played an important role.


Assuntos
Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Hospedeiro Imunocomprometido , Condicionamento Pré-Transplante/efeitos adversos , Viroses/imunologia , Criança , Humanos , Transplante Autólogo , Transplante Homólogo , Viroses/etiologia
9.
Bone Marrow Transplant ; 41 Suppl 2: S107-11, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18545231

RESUMO

Invasive mycoses represent a rare but severe complication following hemopoietic SCT (HSCT) in children. Their incidence is related to the type of donor, being higher after allogeneic transplant, especially from alternative donors. Moreover, the incidence of invasive mycoses varies in the different post transplant phases. Neutropenia, lymphopenia, GvHD, high-dose steroids or other immunosuppressive drugs represent well-known risk factors. The clinical features of invasive mycoses after HSCT in children are similar to those observed in adults, and the diagnostic tools, including Aspergillus galactomannan antigen detection, are feasible also in pediatrics. Mortality due to invasive mycoses after HSCT in children is high.


Assuntos
Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Micoses/etiologia , Aspergilose/diagnóstico , Criança , Galactose/análogos & derivados , Humanos , Mananas/análise , Micoses/prevenção & controle , Fatores de Risco
10.
Bone Marrow Transplant ; 41 Suppl 2: S104-6, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18545230

RESUMO

The incidence of bacteremia following hemopoietic SCT (HSCT) changes over time from the procedure. The first 30 days have the highest incidence, both in autologous and allogeneic HSCT recipients. In the following periods, bacteremia is a frequent complication in allogeneic HSCT, especially from alternative donors. Gram-positive cocci represent the most frequent cause of single-agent bacteremia. Knowledge of epidemiology (incidence and etiology) of bacteremias following HSCT is pivotal for planning management strategies (prevention, diagnosis and therapy) that must be distinct in the different post-transplant period.


Assuntos
Bacteriemia/etiologia , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Bacteriemia/prevenção & controle , Criança , Doença Enxerto-Hospedeiro/complicações , Humanos , Fatores de Risco , Condicionamento Pré-Transplante/efeitos adversos
11.
Bone Marrow Transplant ; 41(4): 339-47, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18026151

RESUMO

We performed a retrospective single center study to define the epidemiology of bacteremias or invasive mycoses in pediatric allogeneic hematopoietic SCT (HSCT) from matched related donors (MRD) or alternative donors (AD). During 119 213 days of follow-up, 156 infections were observed: 130 bacteremias (27 in MRD-HSCT and 103 in AD-HSCT recipients) and 26 invasive mycoses (8 in MRD-HSCT and 18 in AD-HSCT recipients). Overall, the risk of bacteremia was fivefold that of invasive mycosis (P<0.001). AD-HSCT recipients had a higher percentage of infections (89 vs 27%; P<0.001), a higher rate/100 days of immunosuppression (infection rate (IR): 0.21 vs 0.06; P<0.001) and a higher proportion of repeated infections (44 vs 9%; P=0.001). In AD-HSCT, the relative risk of bacteremia was 2.87 in the pre-engraftment period, 5.84 in the early post-engraftment period and 6.46 in the late post-engraftment period (P<0.001) compared to MRD-HSCT. Only after 1 year did the epidemiology become similar. The epidemiology of invasive mycoses did not differ significantly between the two types of transplant.


Assuntos
Bacteriemia/epidemiologia , Infecção Hospitalar/epidemiologia , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Micoses/epidemiologia , Adolescente , Criança , Pré-Escolar , Hospitais Pediátricos/estatística & dados numéricos , Humanos , Incidência , Lactente , Itália/epidemiologia , Estudos Retrospectivos , Transplante Homólogo/efeitos adversos
12.
J Chemother ; 19(3): 339-42, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17594932

RESUMO

Nebulized liposomal amphotericin B (20-15 mg twice daily by nebulizer) was combined with high dose intravenous liposomal amphotericin B (10 mg/kg/day) and high dose caspofungin (100 mg/m(2)) for the treatment of severe, recurrent pulmonary aspergillosis following allogeneic hematopoietic stem cell transplantation from alternative donor in a patient with mitochondrial disease (Pearson's syndrome). This combined treatment was administered for 8 days. Nebulized liposomal amphotericin B was well tolerated. Since severe transplant complications developed, nebulized administration was withdrawn and intravenous doses of liposomal amphotericin B and caspofungin were tapered to usual schedules. Pulmonary aspergillosis responded well to 45 days of combined intravenous antifungal therapies which were maintained for 2 years with secondary prophylaxis, because of persistent immunosuppressive treatment.


Assuntos
Anfotericina B/uso terapêutico , Antifúngicos/uso terapêutico , Aspergilose/tratamento farmacológico , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Pneumopatias Fúngicas/tratamento farmacológico , Doenças Mitocondriais/terapia , Fosfatidilcolinas/uso terapêutico , Fosfatidilgliceróis/uso terapêutico , Administração por Inalação , Anfotericina B/administração & dosagem , Antifúngicos/administração & dosagem , Caspofungina , Combinação de Medicamentos , Quimioterapia Combinada , Equinocandinas , Feminino , Humanos , Injeções Intravenosas , Lipopeptídeos , Peptídeos Cíclicos/uso terapêutico , Fosfatidilcolinas/administração & dosagem , Fosfatidilgliceróis/administração & dosagem , Síndrome , Transplante Homólogo
13.
Pediatr Transplant ; 11(1): 113-6, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17239134

RESUMO

We describe a case of Cryptosporidium infection occurring in a child after allogeneic SCT for acute non-lymphoblastic leukemia. This patient presented an intestinal, biliar, and pancreatic Cryptosporidium disease associated with an intestinal aGvHD. The increase in CD3+/CD4+ cells secondary to the reduction of steroid therapy associated with the improvement of aGvHD and the use of antiparasitic treatments (especially nitazoxanide) improved the infection-related symptoms and led to a complete clearance of the Cryptosporidium.


Assuntos
Antiparasitários/uso terapêutico , Criptosporidiose/terapia , Leucemia Mieloide Aguda/terapia , Transfusão de Linfócitos , Transplante de Células-Tronco , Tiazóis/uso terapêutico , Animais , Antígenos CD/sangue , Biópsia , Complexo CD3/sangue , Linfócitos T CD4-Positivos/transplante , Criança , Colo/parasitologia , Colo/patologia , Criptosporidiose/tratamento farmacológico , Cryptosporidium/isolamento & purificação , Humanos , Masculino , Nitrocompostos , Transplante Homólogo
14.
Pediatr Blood Cancer ; 49(7): 1010-2, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16685738

RESUMO

Tunnel infection is an uncommon but serious complication observed in patients with partially implanted central venous catheters. International guidelines suggest that should include antibiotics and catheter removal. A success rate of only 5-20% was reported without catheter removal. We treated 13 episodes of tunnel Gram-positive bacterial infection occurring in pediatric patients with cancer or serious blood disorders with 24-hr intra-catheter antibiotic continuous infusion. This approach led to a 69% success rate. Continuous infusion might be an attractive option to treat tunnel Gram-positive bacterial infections when catheter removal might not be feasible or advisable.


Assuntos
Antibacterianos/administração & dosagem , Cateterismo Venoso Central/efeitos adversos , Doenças Hematológicas/complicações , Neoplasias/complicações , Infecções Estafilocócicas/tratamento farmacológico , Adolescente , Criança , Pré-Escolar , Feminino , Seguimentos , Humanos , Lactente , Infusões Intra-Arteriais , Masculino , Estudos Retrospectivos , Terapia de Salvação/métodos , Infecções Estafilocócicas/etiologia , Resultado do Tratamento
15.
Oncogene ; 25(50): 6595-603, 2006 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-16702946

RESUMO

Retroviral integration mutagenesis and treatment with the frameshift mutagen ICR191 were used to transform v-H-ras expressing PB-3c cells to interleukin-3 (IL-3) independence. Six clones displayed viral integrations into the 3' region of the IL-3 gene thus acting post-transcriptionally by disrupting the AU-rich instability element. Two clones contained reverse orientation integration into the raf-1 gene revealing an enhancer insertion mechanism. Growth by this mechanism was sensitive to the Raf-1 inhibitor BAY 43-9006 and the Mek inhibitor U0126. Following treatment with ICR191, IL-3-independent clones were recovered and studied by cell fusion. With 21/22 clones, IL-3 independence resulted from a recessive mechanism as cellular hybrids with parental cells reverted to IL-3 dependence. Recessive clone D2c displayed increased phospho-Erk1/2 levels and was growth sensitive to U0126, but not to BAY43-9006. The single dominant clone, D5a, showed no signs of mitogen-activated protein kinases pathway activation but displayed constitutive phosphorylation of Stat5. We conclude that PB-3c has several options to acquire IL-3 growth autonomy involving transcriptional or post-transcriptional mechanisms affecting the distal regulators Erk or Stat5. The reported panel of independent dominant and recessive transformants should provide a useful tool for inhibitor profiling.


Assuntos
Transformação Celular Neoplásica/genética , Células Clonais/citologia , Hematopoese/genética , Interleucina-3/genética , Interleucina-3/fisiologia , Aminacrina/análogos & derivados , Aminacrina/farmacologia , Benzenossulfonatos/farmacologia , Butadienos/farmacologia , Mutação da Fase de Leitura/efeitos dos fármacos , Genes Dominantes , Genes Recessivos , Humanos , MAP Quinase Quinase Quinases/metabolismo , Mutagênese Insercional , Células-Tronco Neoplásicas/citologia , Niacinamida/análogos & derivados , Nitrilas/farmacologia , Compostos de Mostarda Nitrogenada/farmacologia , Compostos de Fenilureia , Proteínas Proto-Oncogênicas c-raf/metabolismo , Piridinas/farmacologia , Retroviridae/genética , Fator de Transcrição STAT5/metabolismo , Sorafenibe , Transfecção
16.
J Chemother ; 17(3): 334-8, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16038529

RESUMO

Metastatic/advanced colorectal cancer is considered a resistant disease and oncologic emergencies secondary to advanced disease may be regarded with a nihilistic attitude. The objective of this report is to emphasize the efficacy of the oxaliplatin/5-fluorouracil/leucovorin regimen (FOLFOX-4) in three patients presenting oncologic emergencies secondary to advanced colon cancer. The first case was a 40-year-old man with severe respiratory insufficiency due to massive carcinomatous lymphangitis; subsequently a cecal adenocarcinoma was diagnosed. The patient's conditions became life-threatening and he was admitted to the intensive care unit. The second case was a 41-year-old woman presenting with fever, abdominal mass and pain. Ultrasound and CT-scan revealed two hepatic masses (13 x 15 and 15 x 20 cm), diagnosed as liver metastases from colon cancer. The patient's condition deteriorated with intestinal obstruction secondary to the large left liver mass. The third case was a 58-year-old woman presenting with hepatic mass, fever and weight loss. Ultrasound and CT-scan showed a liver lesion occupying the right lobe (12 x 14 cm). Ultrasonically-guided biopsy and colonoscopy showed liver metastases from cecal cancer. A 5-fluorouracil/leucovorin regimen failed to improve her clinical condition and she had disease progression, inferior vena cava neoplastic thrombosis and right hydronephrosis. All three patients rapidly improved after a few cycles of oxaliplatin-containing chemotherapy. These cases demonstrate that even patients with advanced colorectal cancer presenting with oncologic emergencies and life-threatening conditions can be successfully treated with the FOLFOX-4 regimen.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Colorretais/complicações , Neoplasias Colorretais/tratamento farmacológico , Doença Aguda , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Feminino , Fluoruracila/administração & dosagem , Humanos , Obstrução Intestinal/etiologia , Leucovorina/administração & dosagem , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/secundário , Linfangite/etiologia , Masculino , Pessoa de Meia-Idade , Compostos Organoplatínicos/administração & dosagem , Resultado do Tratamento
17.
Brain Res ; 1020(1-2): 173-7, 2004 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-15312800

RESUMO

Astrocytes provide structural, trophic and metabolic support to neurons and modulate synaptic activity. Under physiological conditions, neuronal-derived nitric oxide (NO) plays an important role in the modulation of a variety of central nervous system (CNS) functions. NO, although short lived, can travel sufficient distances to be able to act as an intercellular messenger in the brain. Its targets include adjacent neurons and astrocytes. The aim of the present study was performed in order to investigate the effects produced by incubation of lipoproteins, at different times, with human astrocytoma cells and thus measuring NO and its metabolite production. NO and peroxynitrite production, iNOS and nNOS expression by Western immunoblot were evaluated. The LDL and HDL-treated cells showed an increased production of NO, more evident after 12 h, compared to basal levels; concerning peroxynitrite production, LDL and HDL-treated cells showed a higher fluorescence, more evident at 3 h. nNOS and iNOS protein levels were significantly higher in the cells incubated with control LDL and HDL. The present work supports the hypothesis that lipoproteins can induce the formation of reactive astrocytes, inducing iNOS as reported by other authors, giving experimental support to a role played by LDL and HDL inducing a reactive response.


Assuntos
Astrócitos/metabolismo , HDL-Colesterol/fisiologia , LDL-Colesterol/fisiologia , Óxido Nítrico/metabolismo , Ácido Peroxinitroso/metabolismo , Idoso , Astrócitos/enzimologia , Astrocitoma , Indução Enzimática , Humanos , Óxido Nítrico Sintase/metabolismo , Óxido Nítrico Sintase Tipo II , Espécies Reativas de Oxigênio/metabolismo , Fatores de Tempo , Células Tumorais Cultivadas
18.
Eur J Cancer ; 38(18): 2382-7, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12460782

RESUMO

Imaging techniques like ultrasonography (US) or computed tomography (CT) allow full liver scanning and the accurate detection of focal lesions of the liver parenchyma. The occurrence of such lesions in concomitance with non-Hodgkin's lymphoma (NHL), both at the onset of the disease and during follow-up, is of great significance, because it affects staging, prognosis and therapeutic choices. Moreover, the occurrence of focal liver lesions in the setting of a lymphoma is generally considered to be a marker of liver involvement. Nonetheless, data on the prevalence and clinical significance of focal liver lesions occurring in these clinical conditions are limited. Therefore, we retrospectively evaluated the prevalence, nature and clinical significance of focal liver lesions diagnosed by imaging techniques (US and CT) in 414 consecutive NHL patients. The nature of the lesions was established either by US-guided biopsy or by evaluation of the response to chemotherapy for the underlying disease and confirmed by clinical and US follow-up. Subtype of NHL (aggressive or indolent) and Hepatitis C virus (HCV) status were also considered. We detected 129 focal liver lesions (76 at onset and 53 during the follow-up). Hepatic involvement by NHL was found in 69 cases (53%). We observed 7 cases of Hepatocellular Carcinoma (HCC) and 3 cases of metastasis. At onset, only 39% of the detected lesions were due to lymphoma and 58% were benign. Conversely, 74% of the liver lesions detected during the follow-up were due to NHL while 15% to a malignancy other than NHL. All HCC cases occurred in HCV-positive patients with chronic liver disease. We concluded that the focal liver lesions detected at onset in NHL patients are frequently benign and unrelated to the underlying disease. Conversely, most focal liver lesions detected during the follow-up period are malignant and the possibility of HCC occurrence in HCV-positive patients should always be considered. Therefore, these lesions should undergo a full diagnostic work-up, including US-guided biopsy.


Assuntos
Hepatite C Crônica/patologia , Neoplasias Hepáticas/patologia , Linfoma não Hodgkin/patologia , Biópsia por Agulha/métodos , Carcinoma Hepatocelular/diagnóstico por imagem , Carcinoma Hepatocelular/patologia , Cistos/diagnóstico por imagem , Cistos/patologia , Feminino , Seguimentos , Hemangioma/diagnóstico por imagem , Hemangioma/patologia , Hepatite C Crônica/diagnóstico por imagem , Humanos , Hepatopatias/diagnóstico por imagem , Hepatopatias/patologia , Neoplasias Hepáticas/diagnóstico por imagem , Linfoma não Hodgkin/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Tomografia Computadorizada por Raios X/métodos , Ultrassonografia
19.
Cell ; 107(4): 451-64, 2001 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-11719186

RESUMO

Inherently unstable mammalian mRNAs contain AU-rich elements (AREs) within their 3' untranslated regions. Although found 15 years ago, the mechanism by which AREs dictate rapid mRNA decay is not clear. In yeast, 3'-to-5' mRNA degradation is mediated by the exosome, a multisubunit particle. We have purified and characterized the human exosome by mass spectrometry and found its composition to be similar to its yeast counterpart. Using a cell-free RNA decay system, we demonstrate that the mammalian exosome is required for rapid degradation of ARE-containing RNAs but not for poly(A) shortening. The mammalian exosome does not recognize ARE-containing RNAs on its own. ARE recognition requires certain ARE binding proteins that can interact with the exosome and recruit it to unstable RNAs, thereby promoting their rapid degradation.


Assuntos
Regiões 3' não Traduzidas/genética , Inativação Gênica/fisiologia , RNA Mensageiro/metabolismo , Proteínas de Ligação a RNA/fisiologia , Transativadores , Sequência de Aminoácidos , Animais , Pareamento de Bases , Sequência de Bases , Sistema Livre de Células , Genes fos , Humanos , Interleucina-2/genética , Células Jurkat/efeitos dos fármacos , Células Jurkat/metabolismo , Mamíferos/genética , Dados de Sequência Molecular , Poli A/metabolismo , RNA Neoplásico/metabolismo , Proteínas Recombinantes de Fusão/metabolismo , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Nucleotídeos de Timina/farmacologia
20.
RNA ; 7(11): 1578-88, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11720287

RESUMO

To functionally classify AU-rich elements (AREs) from six different cytokine mRNAs, we made use of two previously described HT1080-derived cellular mutants (slowA, slowC) that lack a function required for the rapid degradation of interleukin-3 (IL-3) mRNA. Here we show that the defect is specific for ARE-containing mRNAs, whereas nonsense-mediated decay is intact. Degradation of beta-globin reporter transcripts mediated by the AREs of IL-3, GM-CSF, and TNFalpha, as well as by the structurally different and less potent AREs of IL-2 and IL-6, is impaired in both mutants. All these reporter transcripts are also sensitive to decay induced by ectopic expression of the RNA-binding protein tristetraprolin in the slowC background. Thus, we concluded that the mutants slowA and slowC define a common mRNA degradation pathway that targets cytokine AREs. In NIH3T3 cells, this decay pathway becomes incapacitated by upstream signaling from p38 MAP- or PI3-kinases, which independently stabilize cytokine ARE-containing transcripts. In contrast, c-fos ARE-directed mRNA degradation proceeds through a different pathway not affected by these kinases.


Assuntos
Citocinas/genética , Proteínas de Ligação a DNA , RNA Mensageiro/metabolismo , Elementos de Resposta , Regiões 3' não Traduzidas/metabolismo , Células 3T3 , Animais , Sequência de Bases , Códon sem Sentido , Ativação Enzimática , Fator Estimulador de Colônias de Granulócitos e Macrófagos/genética , Humanos , Proteínas Imediatamente Precoces/metabolismo , Interleucina-2/genética , Interleucina-3/genética , Interleucina-4/genética , Interleucina-6/genética , Camundongos , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Dados de Sequência Molecular , Mutagênese , Fosfatidilinositol 3-Quinases/metabolismo , RNA , Estabilidade de RNA , Proteínas de Ligação a RNA/metabolismo , Tristetraprolina , Células Tumorais Cultivadas , Fator de Necrose Tumoral alfa/genética , Dedos de Zinco , Proteínas Quinases p38 Ativadas por Mitógeno
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