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1.
Cancer Causes Control ; 29(3): 315-324, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29423760

RESUMO

PURPOSE: The Caribbean population faces a growing burden of multiple non-communicable chronic diseases (NCDs). Breast cancer is the leading cause of cancer death for women in the Caribbean. Given the substantial burden of NCDs across the region, cancer prevention and control strategies may need to be specifically tailored for people with multiple co-morbidities. Preventive screening, such as timely mammography, is essential but may be either facilitated or hampered by chronic disease control. The main objective of this study is to examine the relationship between a chronic disease and timely breast cancer screening. METHODS: We conducted a cross-sectional data analysis using baseline data from the Eastern Caribbean Health Outcomes Research Network (ECHORN) Cohort Study-ECS. Our independent variables were presence of chronic diseases (hypertension or diabetes), defined as having been told by a clinical provider. Our dependent variable was timely screening mammography, as defined by receipt of mammography within the past 2 years. We examined bivariate and multivariate associations of covariates and timely screening mammography. RESULTS: In our sample (n = 841), 52% reported timely screening mammography. Among those with timely screening, 50.8% reported having hypertension, and 22.3% reported having diabetes. In our bivariate analyses, both diabetes and hypertension were associated with timely screening mammography. In partially adjusted models, we found that women with diabetes were significantly more likely to report timely screening mammography than women without diabetes. In our fully adjusted models, the association was no longer significant. Having a usual source of healthcare and a woman's island of residence were significantly associated with timely screening mammography (p < 0.05). CONCLUSIONS: We found that half of eligible women received timely screening mammography. Diabetes and hypertension, though common, are not associated with timely screening mammography. Usual source of care remains an important factor to timely breast cancer screening.


Assuntos
Neoplasias da Mama/diagnóstico , Detecção Precoce de Câncer , Doenças não Transmissíveis , Adulto , Idoso , Neoplasias da Mama/epidemiologia , Região do Caribe , Doença Crônica , Estudos de Coortes , Estudos Transversais , Diabetes Mellitus/epidemiologia , Feminino , Humanos , Hipertensão/epidemiologia , Mamografia , Pessoa de Meia-Idade , Doenças não Transmissíveis/epidemiologia , Avaliação de Resultados em Cuidados de Saúde
2.
Br J Cancer ; 107(9): 1481-7, 2012 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-23037712

RESUMO

BACKGROUND: Bevacizumab improves outcome for most recurrent glioblastoma patients, but the duration of benefit is limited and survival after initial bevacizumab progression is poor. We evaluated bevacizumab continuation beyond initial progression among recurrent glioblastoma patients as it is a common, yet unsupported practice in some countries. METHODS: We analysed outcome among all patients (n=99) who received subsequent therapy after progression on one of five consecutive, single-arm, phase II clinical trials evaluating bevacizumab regimens for recurrent glioblastoma. Of note, the five trials contained similar eligibility, treatment and assessment criteria, and achieved comparable outcome. RESULTS: The median overall survival (OS) and OS at 6 months for patients who continued bevacizumab therapy (n=55) were 5.9 months (95% confidence interval (CI): 4.4, 7.6) and 49.2% (95% CI: 35.2, 61.8), compared with 4.0 months (95% CI: 2.1, 5.4) and 29.5% (95% CI: 17.0, 43.2) for patients treated with a non-bevacizumab regimen (n=44; P=0.014). Bevacizumab continuation was an independent predictor of improved OS (hazard ratio=0.64; P=0.04). CONCLUSION: The results of our retrospective pooled analysis suggest that bevacizumab continuation beyond initial progression modestly improves survival compared with available non-bevacizumab therapy for recurrent glioblastoma patients require evaluation in an appropriately randomised, prospective trial.


Assuntos
Inibidores da Angiogênese/administração & dosagem , Anticorpos Monoclonais Humanizados/administração & dosagem , Neoplasias Encefálicas/tratamento farmacológico , Glioblastoma/tratamento farmacológico , Recidiva Local de Neoplasia/tratamento farmacológico , Adulto , Idoso , Inibidores da Angiogênese/efeitos adversos , Anticorpos Monoclonais Humanizados/efeitos adversos , Bevacizumab , Progressão da Doença , Esquema de Medicação , Humanos , Pessoa de Meia-Idade , Estudos Retrospectivos , Análise de Sobrevida , Resultado do Tratamento , Adulto Jovem
3.
Br J Cancer ; 107(8): 1399-408, 2012 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-22976800

RESUMO

BACKGROUND: Tumours are responsive to temozolomide (TMZ) if they are deficient in O(6)-methylguanine-DNA methyltransferase (MGMT), and mismatch repair (MMR) proficient. METHODS: The effect of TMZ on medulloblastoma (MB) cell killing was analysed with clonogenic survival assays. Expression of DNA repair genes and enzymes was investigated using microarrays, western blot, and immunohistochemistry. DNA sequencing and promoter methylation analysis were employed to investigate the cause of loss of the expression of MMR gene MLH1. RESULTS: Temozolomide exhibited potent cytotoxic activity in D425Med (MGMT deficient, MLH1 proficient; IC(50)=1.7 µM), moderate activity against D341Med (MGMT proficient, MLH1 deficient), and DAOY MB cells (MGMT proficient, MLH1 proficient). MGMT inhibitor O(6)-benzylguanine sensitised DAOY, but not D341Med cells to TMZ. Of 12 MB cell lines, D341Med, D283Med, and 1580WÜ cells exhibited MMR deficiency due to MLH1 promoter hypermethylation. DNA sequencing of these cells provided no evidence for somatic genetic alterations in MLH1. Expression analyses of MMR and MGMT in MB revealed that all patient specimens (n=74; expression array, n=61; immunostaining, n=13) are most likely MMR proficient, whereas some tumours had low MGMT expression levels (according to expression array) or were totally MGMT deficient (3 out of 13 according to immunohistochemistry). CONCLUSION: A subset of MB may respond to TMZ as some patient specimens are MGMT deficient, and tumours appear to be MMR proficient.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/genética , Antineoplásicos Alquilantes/uso terapêutico , Neoplasias Cerebelares/genética , Reparo de Erro de Pareamento de DNA/genética , Dacarbazina/análogos & derivados , Resistencia a Medicamentos Antineoplásicos/genética , Meduloblastoma/genética , Proteínas Nucleares/genética , Proteínas Adaptadoras de Transdução de Sinal/biossíntese , Linhagem Celular Tumoral , Neoplasias Cerebelares/tratamento farmacológico , Neoplasias Cerebelares/metabolismo , Criança , Pré-Escolar , Metilases de Modificação do DNA/biossíntese , Metilases de Modificação do DNA/genética , Enzimas Reparadoras do DNA/biossíntese , Enzimas Reparadoras do DNA/genética , Dacarbazina/uso terapêutico , Feminino , Humanos , Masculino , Meduloblastoma/tratamento farmacológico , Meduloblastoma/metabolismo , Proteína 1 Homóloga a MutL , Proteínas Nucleares/biossíntese , O(6)-Metilguanina-DNA Metiltransferase/metabolismo , Temozolomida , Proteínas Supressoras de Tumor/biossíntese , Proteínas Supressoras de Tumor/genética
4.
Br J Radiol ; 85(1012): 382-9, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21224297

RESUMO

OBJECTIVES: The aim of this study was to determine the prognostic significance of changes in parameters derived from diffusion tensor imaging (DTI) that occur in response to treatment with bevacizumab and irinotecan in patients with recurrent glioblastoma multiforme. METHODS: 15 patients with recurrent glioblastoma multiforme underwent serial 1.5 T MRI. Axial single-shot echo planar DTI was obtained on scans performed 3 days and 1 day prior to and 6 weeks after initiation of therapy with bevacizumab and irinotecan. Apparent diffusion coefficient (ADC) and fractional anisotropy (FA) maps were registered to whole brain contrast-enhanced three-dimensional (3D) spoiled gradient recalled and 3D fluid attenuation inversion recovery (FLAIR) image volumes. Anatomic image volumes were segmented to isolate regions of interest defined by tumour-related enhancement (TRE) and FLAIR signal abnormality (FSA). Mean ADC and mean FA were calculated for each region. A Bland-Altman repeatability coefficient was also calculated for each parameter based on the two pre-treatment studies. A patient was considered to have a change in FA or ADC after therapy if the difference between the pre- and post-treatment values was greater than the repeatability coefficient for that parameter. Survival was compared using a Cox proportional hazard model. RESULTS: DTI detected a change in ADC within FSA after therapy in nine patients (five in whom ADC was increased; four in whom it was decreased). Patients with a change in ADC within FSA had significantly shorter overall survival (p=0.032) and progression free survival (p=0.046) than those with no change. CONCLUSION: In patients with recurrent glioblastoma multiforme treated with bevacizumab and irinotecan, a change in ADC after therapy in FSA is associated with decreased survival.


Assuntos
Inibidores da Angiogênese/uso terapêutico , Anticorpos Monoclonais Humanizados/uso terapêutico , Imagem de Tensor de Difusão , Glioblastoma/tratamento farmacológico , Glioblastoma/mortalidade , Adulto , Inibidores da Angiogênese/administração & dosagem , Anisotropia , Anticorpos Monoclonais Humanizados/administração & dosagem , Antineoplásicos Fitogênicos/administração & dosagem , Antineoplásicos Fitogênicos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Bevacizumab , Camptotecina/administração & dosagem , Camptotecina/análogos & derivados , Camptotecina/uso terapêutico , Feminino , Glioblastoma/diagnóstico , Humanos , Irinotecano , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Prognóstico
5.
Br J Radiol ; 84(1000): 327-33, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20959370

RESUMO

OBJECTIVE: The aim of this study was to determine the prognostic significance of the volume and intensity of abnormal (18)F-fluorodeoxyglucose positron emission tomography (FDG-PET) accumulation within areas of contrast enhancement on post-therapeutic volumetric MRI. METHODS: A total of 10 patients with Grade III or IV glioma were treated with resection followed by intracavitary radiation therapy with (131)I-labelled antitenascin monoclonal antibody. Patients underwent serial FDG-PET and 1.5 T MR imaging. For each patient, MR and FDG-PET image volumes at each time point were aligned using a rigid-body normalised mutual information algorithm. Contrast-enhancing regions of interest (ROIs) were defined using a semi-automated k-means clustering technique. Activity within the ROI on the co-registered PET scan was calculated as a ratio (mean activity ratio; MAR) to activity in contralateral normal-appearing white matter (NAWM). The PET lesion was defined as the portion of the ROI associated with activity greater than two standard deviations above the mean in NAWM. Survival was assessed using the logrank test. RESULTS: Larger contrast-enhancing ROIs were strongly associated with an increased MAR (r = 0.51; p<0.002). Enhancing lesions with an MAR >1.2 were associated with decreased survival (p<0.016). In nine patients who died, the MAR on PET correlated inversely with survival duration (r = -0.43; p<0.01), whereas PET lesion volume did not. CONCLUSION: Following intracavitary radiation therapy, the development of contrast-enhancing lesions that are associated with high mean FDG-PET accumulation suggests poor prognosis.


Assuntos
Neoplasias Encefálicas/diagnóstico , Glioma/diagnóstico , Imageamento por Ressonância Magnética/métodos , Tomografia por Emissão de Pósitrons/métodos , Adulto , Idoso , Neoplasias Encefálicas/diagnóstico por imagem , Feminino , Fluordesoxiglucose F18 , Glioma/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Compostos Radiofarmacêuticos
6.
Br J Cancer ; 101(12): 1986-94, 2009 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-19920819

RESUMO

BACKGROUND: We evaluated bevacizumab with metronomic etoposide among recurrent malignant glioma patients in a phase 2, open-label trial. METHODS: A total of 59 patients, including 27 with glioblastoma (GBM) and 32 with grade 3 malignant glioma, received 10 mg kg(-1) bevacizumab biweekly and 50 mg m(-2) etoposide daily for 21 consecutive days each month. The primary end point was a 6-month progression-free survival, and secondary end points included safety and overall survival. Vascular endothelial growth factor (VEGF), VEGFR-2, carbonic anhydrase 9 (CA9) and hypoxia-inducible factor-2alpha (HIF-2alpha) were assessed semiquantitatively in archival tumours using immunohistochemistry and were correlated with outcome. RESULTS: Among grade 3 and GBM patients, the 6-month progression-free survivals were 40.6% and 44.4%, the radiographic response rates were 22% and 37% and the median survivals were 63.1 and 44.4 weeks, respectively. Hypertension predicted better outcome among both grade 3 and GBM patients, whereas high CA9 and low VEGF were associated with poorer progression-free survival (PFS) among those with GBM. The most common grade > or = 3 adverse events included neutropaenia (24%), thrombosis (12%), infection (8%) and hypertension (3%). Two patients had asymptomatic, grade 1 intracranial haemorrhage and one on-study death occurred because of pulmonary embolism. CONCLUSION: Bevacizumab with metronomic etoposide has increased toxicity compared with previous reports of bevacizumab monotherapy. Its anti-tumour activity is similar to that of bevacizumab monotherapy or bevacizumab plus irinotecan. (ClinicalTrials.gov: NCT00612430).


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Encefálicas/tratamento farmacológico , Glioma/tratamento farmacológico , Recidiva Local de Neoplasia/tratamento farmacológico , Administração Oral , Adulto , Idoso , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais/efeitos adversos , Anticorpos Monoclonais Humanizados , Bevacizumab , Biomarcadores Tumorais/análise , Neoplasias Encefálicas/mortalidade , Etoposídeo/administração & dosagem , Etoposídeo/efeitos adversos , Feminino , Glioma/mortalidade , Humanos , Masculino , Pessoa de Meia-Idade , Falha de Tratamento , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores
7.
Mol Pharmacol ; 75(6): 1356-63, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19261750

RESUMO

The presence of DNA damage initiates signaling through the ataxia-telangiectasia mutated kinase (ATM) and the ATM- and the Rad3-related kinase (ATR), which phosphorylate, thus activating, the checkpoint kinases (Chk) 1 and 2, which leads to cell cycle arrest. The bifunctional DNA alkylator 1,3-bis(2-chloroethyl)-1-nitrosourea (BCNU) is cytotoxic primarily by inducing DNA monoadducts and ultimately, interstrand cross-links, which block DNA replication. In this study, we investigated the activation of the ATR-Chk1 pathway in response to BCNU treatment and the dependence of this response on the DNA mismatch repair (MMR) capacity. Medulloblastoma cells were exposed to low and moderate doses of BCNU, and the effects on this DNA damage signaling pathway were examined. In response to BCNU, Chk1 was found to be phosphorylated at serine 345 and exhibited increased kinase activity. Caffeine and wortmannin, which are broad-spectrum inhibitors of ATM and ATR, reduced this phosphorylation. Cell cycle analysis further revealed an accumulation of cells in the S phase in response to BCNU, an effect that was attenuated by caffeine. Small interfering RNA knockdown of ATR also reduced Chk1 phosphorylation after exposure to BCNU. However, knockdown of ATM had no effect on the observed Chk1 phosphorylation, suggesting that ATR was primarily responsible for Chk1 activation. Analysis of Chk1 activation in cells deficient in MMR proteins MutLalpha or MutSalpha indicated that the DNA damage response induced by BCNU was independent of the MMR apparatus. This MMR-independent activation seems to be the result of DNA interstrand cross-link formation.


Assuntos
Antineoplásicos Alquilantes/farmacologia , Carmustina/farmacologia , Proteínas de Ciclo Celular/fisiologia , Reparo de Erro de Pareamento de DNA/fisiologia , Proteínas Quinases/fisiologia , Proteínas Serina-Treonina Quinases/fisiologia , Proteínas Mutadas de Ataxia Telangiectasia , Proteínas de Ciclo Celular/antagonistas & inibidores , Linhagem Celular Tumoral , Quinase 1 do Ponto de Checagem , Dano ao DNA/fisiologia , Enzimas Reparadoras do DNA/genética , Ativação Enzimática , Humanos , Proteínas MutL , Proteína MutS de Ligação de DNA com Erro de Pareamento/genética , Fosforilação , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Subunidades Proteicas/genética , Fase S , Transdução de Sinais
8.
Int J Tuberc Lung Dis ; 12(11): 1279-85, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18926038

RESUMO

SETTING: Low sensitivity of acid-fast bacilli (AFB) sputum smears and absence of productive cough are obstacles to the diagnosis of pulmonary tuberculosis (PTB) in hospitals that lack access to bronchoscopy. OBJECTIVES: To evaluate induced sputum, gastric content, blood and urine specimens to improve PTB diagnosis in patients not diagnosed by expectorated sputum AFB smears. DESIGN: Patients admitted to the medical wards of a large public hospital in Gaborone, Botswana, were prospectively enrolled if they had symptoms consistent with PTB, an abnormal chest radiograph, were treated empirically with anti-tuberculosis chemotherapy or had no improvement on antibiotics, and had a non-productive cough or AFB smear-negative sputum. Induced sputum was stained for AFB and Mycobacterium tuberculosis cultures were performed on induced sputum, gastric contents, urine and blood. RESULTS: Of 140 patients meeting the enrollment criteria, 113 (81%) were human immunodeficiency virus (HIV) positive. Fifty-seven (41%) had PTB based on positive cultures from one or more sites, including 48 (84%) from induced sputum, 17 (30%) urine, 13 (23%) gastric contents and 7 (12%) blood. AFB smears were positive in only 18 (32%) culture-proven PTB cases. CONCLUSION: Induced sputum cultures greatly enhanced M. tuberculosis detection in patients with a high prevalence of HIV/AIDS in a hospital without access to bronchoscopy.


Assuntos
Erros de Diagnóstico/prevenção & controle , Programas de Rastreamento/métodos , Escarro/microbiologia , Tuberculose Pulmonar/prevenção & controle , Adulto , Idoso , Botsuana , Técnicas de Cultura de Células , Citodiagnóstico/métodos , Reações Falso-Negativas , Feminino , Infecções por HIV/microbiologia , Humanos , Masculino , Pessoa de Meia-Idade , Sensibilidade e Especificidade , Tuberculose Pulmonar/virologia
9.
Br J Cancer ; 99(2): 294-304, 2008 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-18594532

RESUMO

TRAIL/Apo-2L has shown promise as an anti-glioma drug, based on investigations of TRAIL sensitivity in established glioma cell lines, but it is not known how accurately TRAIL signalling pathways of glioma cells in vivo are reproduced in these cell lines in vitro. To replicate as closely as possible the in vivo behaviour of malignant glioma cells, 17 early passage glioma cell lines and 5 freshly resected gliomas were exposed to TRAIL-based agents and/or chemotherapeutic drugs. Normal human hepatocytes and astrocytes and established glioma cell lines were also tested. Cross-linked TRAIL, but not soluble TRAIL, killed both normal cell types and cells from three tumours. Cells from only one glioma were killed by soluble TRAIL, although only inefficiently. High concentrations of cisplatin were lethal to glioma cells, hepatocytes and astrocytes. Isolated combinations of TRAIL and chemotherapy drugs were more toxic to particular gliomas than normal cells, but no combination was generally selective for glioma cells. This study highlights the widespread resistance of glioma cells to TRAIL-based agents, but suggests that a minority of high-grade glioma patients may benefit from particular combinations of TRAIL and chemotherapy drugs. In vitro sensitivity assays may help identify effective drug combinations for individual glioma patients.


Assuntos
Antineoplásicos/farmacologia , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Glioma/tratamento farmacológico , Ligante Indutor de Apoptose Relacionado a TNF/farmacologia , Adulto , Idoso , Antineoplásicos/administração & dosagem , Astrócitos/efeitos dos fármacos , Carboplatina/administração & dosagem , Linhagem Celular Tumoral , Cisplatino/administração & dosagem , Dacarbazina/administração & dosagem , Dacarbazina/análogos & derivados , Ensaios de Seleção de Medicamentos Antitumorais , Etoposídeo/administração & dosagem , Feminino , Glioblastoma/tratamento farmacológico , Glioblastoma/patologia , Glioma/patologia , Hepatócitos/efeitos dos fármacos , Humanos , Lomustina/administração & dosagem , Masculino , Glicoproteínas de Membrana/administração & dosagem , Pessoa de Meia-Idade , Procarbazina/administração & dosagem , Proteínas Recombinantes de Fusão/administração & dosagem , Ligante Indutor de Apoptose Relacionado a TNF/administração & dosagem , Temozolomida , Fator de Necrose Tumoral alfa/administração & dosagem , Vincristina/administração & dosagem
10.
Curr Cancer Drug Targets ; 8(3): 172-9, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18473730

RESUMO

The total expression profiles of two medulloblastoma cell lines resistant to the preactivated form of cyclophosphamide (4-hydroperoxycyclophosphamide, 4-HC) were examined using the Affymetrix GeneChip U133A array. Our primary objective was to look for possible genes, other than the well-studied aldehyde dehydrogenases (ALDH) that may be involved in cyclophosphamide (CP) resistance in medulloblastomas. We present here the lists of the most highly upregulated [30 for D341 MED (4-HCR); 20 for D283 MED (4-HCR)] and downregulated [19 for D341 MED (4-HCR); 15 for D283 MED (4-HCR)] genes which may be involved in conferring CP-resistance to the two medullobalstoma cell lines. The lists of genes from the two sublines almost had no overlap, suggesting different mechanisms of CP-resistance. One of the most noteworthy upregulated gene is TAP1 [90-fold increase in D341 MED (4-HCR) relative to D341 MED]. TAP1, a protein belonging to the ABC transporter family is normally involved in major histocompatibility class I (MHC I) antigen processing. This suggests the possible role of multidrug resistance (MDR), albeit atypical (which means it does not involve the usual MDR1 and MRP glycoproteins), in medulloblastoma's CP-resistance. Apart from TAP1, a number of other genes involved in MHC1 processing were upregulated in D341 MED (4HCR). D341 MED (4-HCR) also had a 20-fold increase in the expression of the aldo-keto reductase gene, AKR1B10, which may deactivate the reactive cyclophosphamide metabolite, aldophosphamide. For D283 MED (4-HCR), the most notable increase in expression is that of ALDH1B1, a member of the aldehyde dehydrogenase (ALDH) family of proteins.


Assuntos
Antineoplásicos Alquilantes/uso terapêutico , Neoplasias Cerebelares/genética , Ciclofosfamida/análogos & derivados , Resistencia a Medicamentos Antineoplásicos/genética , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Meduloblastoma/genética , Membro 2 da Subfamília B de Transportadores de Cassetes de Ligação de ATP , Transportadores de Cassetes de Ligação de ATP/genética , Aldeído Desidrogenase , Família Aldeído Desidrogenase 1 , Aldeído-Desidrogenase Mitocondrial , Aldeído Oxirredutases/genética , Aldeído Redutase/genética , Aldo-Ceto Redutases , Linhagem Celular Tumoral , Neoplasias Cerebelares/tratamento farmacológico , Neoplasias Cerebelares/enzimologia , Ciclofosfamida/uso terapêutico , Interpretação Estatística de Dados , Perfilação da Expressão Gênica/métodos , Regulação Enzimológica da Expressão Gênica , Genótipo , Humanos , Meduloblastoma/tratamento farmacológico , Meduloblastoma/enzimologia , Análise de Sequência com Séries de Oligonucleotídeos , Fenótipo
11.
Plast Reconstr Surg ; 117(7 Suppl): 175S-190S; discussion 191S-192S, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16799386

RESUMO

Hyperbaric oxygen has been advocated, both as an adjunctive or primary form of treatment, for a variety of disorders, including gas gangrene, osteoradionecrosis, and carbon monoxide poisoning. It has also been used to improve ischemic wounds before skin grafting and to support ischemic flaps. In this review, we analyze the available literature that investigates the use of hyperbaric oxygen for composite grafts, skin grafts, random flaps, distant flaps, and free flaps. An appraisal of the level of evidence for each of these uses of hyperbaric oxygen is offered. Although there are a significant amount of animal data supporting the application of hyperbaric oxygen for grafts and flaps, there is very little clinical information other than case reports and series to sustain its choice over other modalities of therapy. Multicenter prospective clinical studies are clearly needed comparing hyperbaric oxygen to other mechanical or pharmacologic interventions to improve wound healing for grafting or to support flap survival.


Assuntos
Oxigenoterapia Hiperbárica , Transplante de Pele/métodos , Retalhos Cirúrgicos/irrigação sanguínea , Animais , Medicina Baseada em Evidências , Sobrevivência de Enxerto/fisiologia , Humanos , Modelos Animais , Cicatrização/fisiologia
12.
Bioconjug Chem ; 17(1): 195-203, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16417269

RESUMO

Carbohydration of N-terminus and substitution of a threonine for the threoninol residue at the C-terminus of Tyr3-octreotide (TOC) has resulted in improved pharmacokinetics and tumor targeting of its radioiodinated derivatives. Yet, these peptides are very susceptible to in vivo deiodination due to the similarity of monoiodotyrosine (MIT) to thyroid hormone. The goal of this work was to develop octreotate analogues containing both a sugar moiety and a nontyrosine prosthetic group on which a radioiodine or 211At can be introduced. Solid-phase synthesis and subsequent modifications delivered an iodo standard of the target peptide N(alpha)-(1-deoxy-D-fructosyl)-N(epsilon)-(3-iodobenzoyl)-Lys0-octreotate (GIBLO) and the corresponding tin precursor N(alpha)-(1-deoxy-D-fructosyl)-N(epsilon)-[(3-tri-n-butylstannyl)benzoyl]-Lys0-octreotate (GTBLO). GIBLO displaced [125I]TOC from somatostatin receptor subtype 2 (SSTR2)-positive AR42J rat pancreatic tumor cell membranes with an IC50 of 0.46 +/- 0.05 nM suggesting that GIBLO retained affinity to SSTR2. GTBLO was radiohalogenated to [131I]GIBLO and N(alpha)-(1-deoxy-D-fructosyl)-N(epsilon)-(3-[211At]astatobenzoyl)-Lys0-octreotate ([211At]GABLO) in 21.2 +/- 4.9% and 46.8 +/- 9.5% radiochemical yields, respectively. From a paired-label internalization assay using D341 Med medulloblastoma cells, the maximum specific internalized radioactivity from [131I]GIBLO was 1.78 +/- 0.8% of input dose compared to 9.67 +/- 0.43% for N(alpha)-(1-deoxy-D-fructosyl)-[125I]iodo-Tyr3-octreotate ([125I]I-Gluc-TOCA). Over a 4 h period, the extent of internalization of [131I]GIBLO and [211At]GABLO was similar in this cell line. In D341 Med murine subcutaneous xenografts, the uptake of [125I]I-Gluc-TOCA at 0.5, 1 and 4 h was 21.5 +/- 4.0% ID/g, 18.8 +/- 7.7% ID/g, and 0.9 +/- 0.4% ID/g, respectively. In comparison, these values for [131I]GIBLO were 6.9 +/- 1.2% ID/g, 4.7 +/- 1.4% ID/g, and 0.8 +/- 0.5% ID/g. Both in vitro and in vivo catabolism studies did not suggest the severance of the lys0 along with its appendages from the peptide. Taken together, although GIBLO maintained affinity to SSTR2, its tumor uptake both in vitro and in vivo was substantially lower than that of I-Gluc-TOCA suggesting other factors such as net charge and overall geometry of the peptide may be important.


Assuntos
Peptídeos Cíclicos/química , Peptídeos/síntese química , Peptídeos/farmacocinética , Estanho/química , Animais , Astato , Linhagem Celular Tumoral , Glicosilação , Humanos , Radioisótopos do Iodo , Meduloblastoma/metabolismo , Camundongos , Camundongos Nus , Transplante de Neoplasias , Peptídeos/metabolismo , Ratos , Receptores de Somatostatina/metabolismo , Distribuição Tecidual
13.
Int Immunopharmacol ; 6(1): 26-35, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16332510

RESUMO

Nicotine, the major addictive component of tobacco, is an immunomodulator that impacts on many cells, including immune cells involved in inflammatory processes. Nicotine also induces oxidative damage to the vascular endothelium and accentuates lipid peroxidation, resulting in vascular cell dysfunction. Furthermore, vascular endothelial cells produce growth factors, such as cytokines and chemokines capable of stimulating and recruiting immune cells to atheromatous lesions. In addition, bacterial products including lipopolysaccharides (LPS), a major component of Gram negative bacterial cell walls, activate gene expression resulting in inflammatory cytokine production causing further damage to the vasculature. In the present study, the combined effects of nicotine and bacterial LPS on the expression of IL-6, IL-8, GRO-alpha and MCP-1 in cell lines of human coronary artery endothelial cells (HCAEC) and pulmonary monocytes (THP-1) were examined by quantitative real-time PCR and ELISA. Results showed that nicotine suppressed the LPS induced production of IL-6 and IL-8 in both cell lines. Since cytokines which alter homeostasis of both vascular endothelial and immune cells are critical for the atherogenic process, further studies are warranted to examine in detail the role of nicotine in terms of effects on inflammatory reactions, including those induced by bacterial infection.


Assuntos
Citocinas/biossíntese , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/imunologia , Lipopolissacarídeos/toxicidade , Monócitos/efeitos dos fármacos , Monócitos/imunologia , Nicotina/toxicidade , Aterosclerose/etiologia , Linhagem Celular , Células Cultivadas , Quimiocina CCL2/biossíntese , Quimiocina CCL2/genética , Quimiocina CXCL1 , Quimiocinas CXC/biossíntese , Quimiocinas CXC/genética , Vasos Coronários/efeitos dos fármacos , Vasos Coronários/imunologia , Citocinas/genética , Humanos , Infecções/complicações , Peptídeos e Proteínas de Sinalização Intercelular/biossíntese , Peptídeos e Proteínas de Sinalização Intercelular/genética , Interleucina-6/biossíntese , Interleucina-6/genética , Interleucina-8/biossíntese , Interleucina-8/genética , Lipopolissacarídeos/administração & dosagem , Nicotina/administração & dosagem , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
14.
Ann Plast Surg ; 56(1): 72-7, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16374100

RESUMO

Piezoelectric sensors have been shown to respond reproducibly to changes in tissue mechanical properties surrounding an implant over a 4-month period. The vibrational amplitude at a frequency corresponding to the radial resonance shows a statistically significant change over time. The initial period of inflammation is marked by a significant reduction in amplitude, which is indicative of an increase in viscous dissipation of the tissue. As collagen displaces the cellular response, the amplitude continues to decrease. Finally, as the tissue matures, the capsule becomes stiffer, and the viscous dissipation lessens. These results are consistent with qualitative assessments of explanted capsules. Strain gauges encased in a monolithic block of silicone exhibited a greater degree of variability, yet show similar trends over time. The strain increases in the initial 4-week period and remains relatively steady over the following 4 weeks. Beyond 8 weeks, the gauges begin to extrude from the animal or suffer a loss of electrical continuity. Steps are being taken to improve the strain sensor longevity in the animals.


Assuntos
Reação a Corpo Estranho/patologia , Reação a Corpo Estranho/prevenção & controle , Teste de Materiais/instrumentação , Próteses e Implantes , Animais , Condutividade Elétrica , Eletrodos Implantados , Masculino , Ratos , Ratos Sprague-Dawley
15.
J. venom. anim. toxins incl. trop. dis ; 11(4): 605-609, out.-dez. 2005.
Artigo em Inglês | LILACS | ID: lil-417730

RESUMO

Laboratory animals are fundamental to study immunological aspects and the efficacy of new drugs to treat leishmaniasis. However, we do not have practical and good animal models to study leishmaniasis caused by Leishmania (Viannia) braziliensis - L(V)b. In this study, thirty-two experimental animals (Cavia porcellus) were injected in the hind foot with 3x105 promastigote forms of L(V)b. The animals were followed for eight weeks. None of the experimental animals developed lesions or presented the parasite in any of the tests performed (histopathological exam, smears, culture, inoculation in hamsters, and polymerase chain reaction)


Assuntos
Animais , Cobaias , Cobaias/parasitologia , Leishmania braziliensis/efeitos dos fármacos , Leishmania braziliensis/parasitologia
17.
J Invest Surg ; 17(5): 271-81, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15385260

RESUMO

The insertion of a foreign substance, such as a breast implant into mammalian soft tissues, evokes a wound healing response that culminates in a dense connective-tissue envelope or capsule surrounding the implant. Several biodegradable products, such as Seprafilm (carboxymethylcellulose and hyaluronic acid) and Interceed (oxidized regenerated cellulose), have been demonstrated to inhibit adhesions in abdominal and gynecologic surgery. The ability of these cellulose compounds to inhibit capsule formation was addressed in this investigation. Twenty-eight rats were implanted intermuscularly with either plain silicone discs (10 animals), discs wrapped in Seprafilm (10 animals), or discs covered with Interceed (8 animals). Additional control animals (6 animals) consisted of two that had sham operations, two animals implanted with Seprafilm only, and two more implanted with Interceed only. Animals were sacrificed in pairs at varying time intervals after implantation (2, 4, 8, 12, and 16 wk), and the tissues around the silicone discs were analyzed with light microscopy. Control animals were sacrificed at 8 wk. Both Interceed and Seprafilm slowed the formation of a capsule around the implanted silicone discs as both products were degraded. Evidence of residual material, presumably Seprafilm and Interceed, was seen intracellularly in animals 3 to 4 mo, respectively, after implantation. However, neither material prevented the eventual formation of a fibrous capsule around the silicone discs. The results of this study suggest that encapsulating foreign substances with these types of biodegradable materials will not significantly hinder capsule formation. A more direct attack on the wound healing mechanism may provide a definitive solution for capsule problems with implanted materials.


Assuntos
Materiais Biocompatíveis/farmacologia , Celulose Oxidada/farmacologia , Implantes Experimentais , Cicatrização/efeitos dos fármacos , Animais , Biodegradação Ambiental , Ácido Hialurônico , Masculino , Ratos , Ratos Sprague-Dawley , Silicones
19.
Int J Gynecol Cancer ; 12(6): 773-6, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12445259

RESUMO

Depression in cancer patients is common and may affect treatment outcome either directly (by lowering defenses) or indirectly (by lowering compliance). Neoadjuvant chemotherapy for advanced uterine cervix or breast cancer is a strenuous undertaking and may lead to depression and impair patients' willingness to comply with the rest of the treatment (eg, surgery or radiotherapy). We compare Beck Depression Inventory (BDI) scores both before and after neoadjuvant chemotherapy in order to verify if depression influences treatment outcome. We studied 22 advanced uterine cervix and 20 breast cancer patients submitted to three courses of neoadjuvant chemotherapy. We used cisplatin and ifosfamide for cervix, and fluorouracil, adriamycin, and cyclophosphamide for breast cancer. We did not identify significant differences in the number of depressed patients, before and after treatment. Cognitive affective, somatic-performance, and total BDI scores were not significantly different from before to after chemotherapy for both breast and uterine cervix cancer. After treatment, the number of depressive breast cancer patients increased while the number of uterine cervix cancer patients decreased. This trend to depression was found more often in less responsive breast cancer patients than in the more responsive cervix cancer patients. We were not able to link depression to treatment failure or success, but patients who responded to treatment were less depressed at the end of treatment.


Assuntos
Neoplasias da Mama/psicologia , Depressão , Neoplasias Uterinas/psicologia , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Cisplatino/administração & dosagem , Ciclofosfamida/administração & dosagem , Doxorrubicina/administração & dosagem , Feminino , Fluoruracila/administração & dosagem , Humanos , Ifosfamida/administração & dosagem , Pessoa de Meia-Idade , Terapia Neoadjuvante , Resultado do Tratamento , Recusa do Paciente ao Tratamento , Neoplasias Uterinas/tratamento farmacológico , Neoplasias Uterinas/patologia
20.
Int Immunopharmacol ; 2(10): 1403-9, 2002 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12400870

RESUMO

It has been recently reported that nicotine, the addictive component of tobacco, is an important modulator at the level of immune cell apoptosis or programmed cell death. Apoptosis is a process that helps maintain the homeostasis of the vascular endothelium and vascular smooth muscle cells, and alteration of the apoptotic process has been associated with cardiovascular diseases. The present study examined the effects and the mechanisms of action of nicotine on apoptosis in human coronary artery endothelial cells (HCAECs). Cultured HCAECs were treated with nicotine at a concentration that correlates with the tissue level of smokers (1 microg/ml), concurrently with tumor necrosis factor-alpha (TNF-alpha) and dexamethasone to induce apoptosis. The data showed that nicotine significantly inhibited apoptosis in HCAECs, as verified by the decreased expression level of active caspases compared to cells treated with the apoptosis inducers alone. This decrease was blocked by the addition of d-tubocurarine chloride (d-TC), a general nicotinic receptor antagonist, providing evidence that this action of nicotine was receptor-mediated. The findings were further confirmed by TUNEL assay for DNA fragmentation, a biochemical marker of apoptosis. This action of nicotine on apoptosis in human coronary artery endothelial cells suggests that nicotine may have an impact on cardiovascular pathology and atherogenesis.


Assuntos
Apoptose/efeitos dos fármacos , Vasos Coronários/efeitos dos fármacos , Endotélio Vascular/efeitos dos fármacos , Nicotina/farmacologia , Divisão Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Vasos Coronários/citologia , Fragmentação do DNA , Endotélio Vascular/citologia , Humanos , Marcação In Situ das Extremidades Cortadas , Tubocurarina/farmacologia
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