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1.
Rev Esp Med Nucl Imagen Mol ; 36(5): 285-291, 2017.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-28341228

RESUMO

OBJECTIVE: To evaluate the efficiency of radioguided occult lesion localising in non-palpable breast lesions (NPBL) compared to the surgical wire technique. METHOD: A prospective study was conducted on 161 women with NPBL, of whom 80 marked with the wire (group 1), whereas 81 women were marked with an intratumour injection of 99mTc-nanocoloid (group 2). The NPBL were located by ultrasound or stereotactic guidance. The lumpectomies were performed following the wire direction in group 1, and with the aid of a gamma-probe in group 2. Surgical margins were then checked, determining the need of extension if the margin was less than 5mm in the intra-surgical study, and less than 2mm in the deferred study. Data were collected on the mean number detected by surgery, surgical margins, number of extensions, presence of residual tumour in the extension, second surgeries, lumpectomy volume, as well as total resected volume, volume/tumour ratio, and complications. RESULTS: No significant differences were observed between the two groups in the mean number detected, surgical margins, number of extensions, presence of residual tumour in the extension, second surgeries, lumpectomy volume, total resected volume, volume/tumour ratio or complications. The multivariate analysis showed the determining factors of the resected volume were the radiological guidance technique, as well as the surgeon. CONCLUSIONS: The radioguided occult lesion localising technique helps in the detection and resection of NPBL with the same efficiency as the surgical wire, and adds the possibility of sentinel node detection in the same surgery. The determining factors of the resected volume were the radiological guidance technique and the surgeon.


Assuntos
Doenças Mamárias/cirurgia , Neoplasias da Mama/cirurgia , Mastectomia Segmentar/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Doenças Mamárias/diagnóstico por imagem , Neoplasias da Mama/diagnóstico por imagem , Feminino , Humanos , Pessoa de Meia-Idade , Palpação , Estudos Prospectivos , Compostos Radiofarmacêuticos , Cirurgia Assistida por Computador , Agregado de Albumina Marcado com Tecnécio Tc 99m
2.
Ultrason Sonochem ; 21(4): 1570-7, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24530142

RESUMO

A rapid in situ biosynthesis of gold nanoparticles (AuNPs) is proposed in which a geranium (Pelargonium zonale) leaf extract was used as a non-toxic reducing and stabilizing agent in a sonocatalysis process based on high-power ultrasound. The synthesis process took only 3.5 min in aqueous solution under ambient conditions. The stability of the nanoparticles was studied by UV-Vis absorption spectroscopy with reference to the surface plasmon resonance (SPR) band. AuNPs have an average lifetime of about 8 weeks at 4 °C in the absence of light. The morphology and crystalline phase of the gold nanoparticles were characterized by transmission electron microscopy (TEM). The composition of the nanoparticles was evaluated by electron diffraction and X-ray energy dispersive spectroscopy (EDS). A total of 80% of the gold nanoparticles obtained in this way have a diameter in the range 8-20 nm, with an average size of 12±3 nm. Fourier transform infrared spectroscopy (FTIR) indicated the presence of biomolecules that could be responsible for reducing and capping the biosynthesized gold nanoparticles. A hypothesis concerning the type of organic molecules involved in this process is also given. Experimental design linked to the simplex method was used to optimize the experimental conditions for this green synthesis route. To the best of our knowledge, this is the first time that a high-power ultrasound-based sonocatalytic process and experimental design coupled to a simplex optimization process has been used in the biosynthesis of AuNPs.


Assuntos
Geranium/química , Ouro/química , Nanopartículas Metálicas/química , Extratos Vegetais/química , Folhas de Planta/química , Sonicação/métodos , Catálise , Técnicas de Química Sintética , Sonicação/instrumentação
3.
Br J Cancer ; 110(5): 1179-88, 2014 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-24423923

RESUMO

BACKGROUND: In experimental models of glioblastoma multiforme (GBM), irradiation (IR) induces local expression of the chemokine CXCL12/SDF-1, which promotes tumour recurrence. The role of CXCR7, the high-affinity receptor for CXCL12, in the tumour's response to IR has not been addressed. METHODS: We tested CXCR7 inhibitors for their effects on tumour growth and/or animal survival post IR in three rodent GBM models. We used immunohistochemistry to determine where CXCR7 protein is expressed in the tumours and in human GBM samples. We used neurosphere formation assays with human GBM xenografts to determine whether CXCR7 is required for cancer stem cell (CSC) activity in vitro. RESULTS: CXCR7 was detected on tumour cells and/or tumour-associated vasculature in the rodent models and in human GBM. In human GBM, CXCR7 expression increased with glioma grade and was spatially associated with CXCL12 and CXCL11/I-TAC. In the rodent GBM models, pharmacological inhibition of CXCR7 post IR caused tumour regression, blocked tumour recurrence, and/or substantially prolonged survival. CXCR7 expression levels on human GBM xenograft cells correlated with neurosphere-forming activity, and a CXCR7 inhibitor blocked sphere formation by sorted CSCs. CONCLUSIONS: These results indicate that CXCR7 inhibitors could block GBM tumour recurrence after IR, perhaps by interfering with CSCs.


Assuntos
Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/radioterapia , Glioblastoma/tratamento farmacológico , Glioblastoma/radioterapia , Receptores CXCR/antagonistas & inibidores , Animais , Neoplasias Encefálicas/patologia , Quimiocina CXCL11/metabolismo , Quimiocina CXCL12/metabolismo , Glioblastoma/patologia , Humanos , Camundongos , Camundongos Nus , Recidiva Local de Neoplasia/metabolismo , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/metabolismo , Ratos , Ratos Sprague-Dawley , Receptores CXCR/metabolismo
4.
Clin Transl Oncol ; 16(1): 96-101, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23632814

RESUMO

PURPOSE: The objective of this study is to evaluate the tolerability and outcome of craniospinal irradiation (CSI) with helical tomotherapy (HT) in the treatment of medulloblastoma. METHODS: We evaluated 19 consecutive patients with primary medulloblastoma who were treated with HT from 2007 through 2010. HT regimens to the neuroaxis included: 23.4 Gy at 1.8 Gy/fraction (N = 10), 36 Gy at 1.8 Gy/fraction (N = 7), and 39 Gy bid at 1.3 Gy/fraction (N = 2). The tumor bed received 54-60 Gy. Potential associations between patient, treatment, and toxicity factors and overall survival (OS) were assessed in univariate analyses using the Cox proportional hazards model. Spearman's rank correlation coefficient was used to correlate potential risk factors with the grade of acute toxicity. RESULTS: The median age at diagnosis was 5 years (range 2-14) and the median follow-up for alive patients (N = 14) 40 months (range 10-62). Two- and three-year overall survival was 75 and 68 %, respectively. The most common acute toxicity was hematological (79 %), being grade 2 and grade 3 in 4 (21 %) and 11 (58 %) cases, respectively. No grade ≥2 late toxicities were observed. Higher grades of acute body toxicity were found in older children (P = 0.004). Longer time between diagnosis and radiation therapy was correlated with shorter OS (P = 0.03). In addition, higher grades of acute thrombocytopenia were associated with shorter OS (P = 0.03). CONCLUSIONS: CSI delivered with HT for medulloblastoma is well tolerated with low rates of severe acute toxicity. Further research is necessary to assess late toxicity with a longer follow-up.


Assuntos
Neoplasias Cerebelares/radioterapia , Radiação Cranioespinal/métodos , Meduloblastoma/radioterapia , Radioterapia de Intensidade Modulada , Adolescente , Criança , Pré-Escolar , Radiação Cranioespinal/efeitos adversos , Feminino , Humanos , Masculino , Radioterapia de Intensidade Modulada/efeitos adversos , Resultado do Tratamento
5.
Ann Oncol ; 24(1): 67-74, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23002278

RESUMO

BACKGROUND: The purpose of this study was to evaluate the actuarial risk of local and regional failure in patients with completely resected non-small-cell lung cancer (NSCLC), and to assess surgical and pathological factors affecting this risk. PATIENTS AND METHODS: Between January 1998 and December 2009, 1402 consecutive stage I-III (N0-N1) NSCLC patients underwent complete resection without adjuvant radiation therapy. The median follow-up was 42 months. RESULTS: Local-regional recurrence was identified in 9% of patients, with local failure alone in 3% of patients, regional failure alone in 4% of patients, and both local and regional failure simultaneously in 2% of patients. Patients who had local failure were found to be at increased risk of mortality. By multivariate analyses, three variables were shown to be independently significant risk factors for local [surgical procedure (single/multiple wedges+segmentectomy versus lobectomy+bilobectomy+pneumonectomy), tumor size>2.7 cm, and visceral pleural invasion] and regional (pathologic N1 stage, visceral pleural invasion, and lymphovascular space invasion, LVI) recurrence, respectively. CONCLUSION: Patients with N0-N1 disease have low rates of locoregional recurrence after surgical resection. However, several prognostic factors can be identified that increase this risk and identify patients who may benefit from adjuvant treatment.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/patologia , Neoplasias Pulmonares/patologia , Recidiva Local de Neoplasia , Seleção de Pacientes , Adulto , Idoso , Idoso de 80 Anos ou mais , Área Sob a Curva , Carcinoma Pulmonar de Células não Pequenas/radioterapia , Carcinoma Pulmonar de Células não Pequenas/cirurgia , Feminino , Humanos , Neoplasias Pulmonares/radioterapia , Neoplasias Pulmonares/cirurgia , Masculino , Pessoa de Meia-Idade , Curva ROC , Fatores de Risco
6.
Clin Transl Oncol ; 15(6): 484-91, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23143953

RESUMO

PURPOSE: To investigate the outcomes and risk factors of patients treated with stereotactic ablative radiotherapy (SABR) delivered by image-guided helical tomotherapy (HT) for extracranial oligometastases. METHODS: From August 2006 through July 2011, 42 consecutive patients (median age 69 years [range 16-87]) with oligometastases (≤3) received HT to all known cancer sites (lung, n = 28; liver, n = 12; adrenal, n = 2). Prognostic factors were assessed by Cox's proportional hazards regression analysis. RESULTS: A total of 60 lesions were treated with hypofractionated HT (median dose 39 Gy [range 36-72.5]; median dose per fraction 12 Gy [range 5-20]). Complete or partial response was observed in 40 (54 %) patients. With a median follow-up period of 15 months, 1- and 2-year overall survival (OS) was 84 and 63 %, respectively; and 1- and 2-year local control (LC) was 92 and 86 %, respectively. Four patients had pneumonitis Grade ≥2 and two patients had lower gastrointestinal toxicity Grade ≥2. Only the lack of complete/partial response was associated with higher risk of mortality on univariate (HR = 3.8, P = 0.04) and multivariate (HR = 6.6, P = 0.01) analyses. CONCLUSIONS: SABR delivered by image-guided HT is well tolerated and offers adequate LC with low acute morbidity in patients with extracranial oligometastatic disease. We found that the response to HT was the only predictor for OS.


Assuntos
Neoplasias das Glândulas Suprarrenais/cirurgia , Neoplasias Hepáticas/cirurgia , Neoplasias Pulmonares/cirurgia , Neoplasias/cirurgia , Radiocirurgia , Radioterapia de Intensidade Modulada , Cirurgia Assistida por Computador , Adolescente , Neoplasias das Glândulas Suprarrenais/mortalidade , Neoplasias das Glândulas Suprarrenais/secundário , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Seguimentos , Humanos , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/secundário , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/secundário , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/mortalidade , Recidiva Local de Neoplasia/patologia , Recidiva Local de Neoplasia/cirurgia , Estadiamento de Neoplasias , Neoplasias/mortalidade , Neoplasias/patologia , Prognóstico , Taxa de Sobrevida , Adulto Jovem
7.
Science ; 337(6095): 713-7, 2012 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-22879514

RESUMO

There is a critical need for improved methane-oxidation catalysts to both reduce emissions of methane, a greenhouse gas, and improve the performance of gas turbines. However, materials that are currently available either have low activity below 400°C or are unstable at higher temperatures. Here, we describe a supramolecular approach in which single units composed of a palladium (Pd) core and a ceria (CeO(2)) shell are preorganized in solution and then homogeneously deposited onto a modified hydrophobic alumina. Electron microscopy and other structural methods revealed that the Pd cores remained isolated even after heating the catalyst to 850°C. Enhanced metal-support interactions led to exceptionally high methane oxidation, with complete conversion below 400°C and outstanding thermal stability under demanding conditions.

8.
Clin Pharmacol Ther ; 89(5): 726-34, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21451509

RESUMO

The safety and pharmacokinetic (PK)/pharmacodynamic (PD) profile of the novel CCR1 antagonist CCX354 was evaluated in double-blind, placebo-controlled, single- and multiple-dose phase I studies (1-300 mg/day oral doses). CCX354 was well tolerated and displayed a linear dose-exposure profile, with half-life approaching 7 h at the 300-mg dose. The extent of CCR1 receptor blockade on blood monocytes, which correlated well with plasma concentrations of the drug, was assessed using fluorescently labeled CCL3 binding in whole blood from phase I subjects. High levels of receptor coverage at the 12-h time point were achieved after a single dose of 100 mg CCX354. Preclinical studies indicate that effective blockade of inflammatory cell infiltration into tissues requires ≥90% CCR1 inhibition on blood leukocytes at all times. The comparison of the properties of CCX354 with those published for other CCR1 antagonists has informed the dose selection for ongoing clinical development of CCX354 in rheumatoid arthritis (RA).


Assuntos
Mediadores da Inflamação/farmacologia , Mediadores da Inflamação/farmacocinética , Quinoxalinas/farmacologia , Quinoxalinas/farmacocinética , Receptores CCR1/antagonistas & inibidores , Adulto , Animais , Relação Dose-Resposta a Droga , Método Duplo-Cego , Feminino , Humanos , Mediadores da Inflamação/administração & dosagem , Masculino , Pessoa de Meia-Idade , Monócitos/efeitos dos fármacos , Monócitos/metabolismo , Monócitos/patologia , Ligação Proteica/fisiologia , Quinoxalinas/administração & dosagem , Coelhos , Ratos , Ratos Wistar , Receptores CCR1/metabolismo , Adulto Jovem
9.
Bioorg Med Chem Lett ; 17(8): 2188-92, 2007 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-17329103

RESUMO

A novel series of imidazolylpyrimidines were found to possess inhibitory activity against the human CMV UL70 primase. Extensive SAR studies on an HTS lead led to potent, orally bioavailable compounds with anti-CMV IC(50) values of 150 nM in both viral yield and viral DNA replication assays and with a much reduced cytotoxicity compared to marketed treatments ganciclovir and cidofovir.


Assuntos
Antivirais/química , Citomegalovirus/efeitos dos fármacos , DNA Primase/antagonistas & inibidores , Pirimidinas/farmacologia , Administração Oral , Animais , Antivirais/farmacologia , Disponibilidade Biológica , Citomegalovirus/enzimologia , Replicação do DNA , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Humanos , Concentração Inibidora 50 , Pirimidinas/química , Pirimidinas/toxicidade , Ratos , Relação Estrutura-Atividade , Carga Viral
10.
Bioorg Med Chem Lett ; 16(18): 4879-83, 2006 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-16814545

RESUMO

Infection by human cytomegalovirus (hCMV) remains a potent threat to susceptible people throughout the world. We have discovered a series of imidazolyl-pyrimidine compounds, which were found to be irreversible inhibitors of the hCMV UL70 primase based on results from radiolabeling and SAR studies. Two promising analogs are described that rival ganciclovir and cidofovir in antiviral potency and possess improved cytotoxicity profiles.


Assuntos
Citomegalovirus/efeitos dos fármacos , Citomegalovirus/enzimologia , DNA Primase/antagonistas & inibidores , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/farmacologia , Antivirais/síntese química , Antivirais/química , Antivirais/farmacologia , Medula Óssea/efeitos dos fármacos , Linhagem Celular , DNA Primase/metabolismo , Inibidores Enzimáticos/química , Humanos , Estrutura Molecular , Pirimidinas/química , Relação Estrutura-Atividade
11.
Gastroenterol Hepatol ; 26(7): 411-6, 2003.
Artigo em Espanhol | MEDLINE | ID: mdl-12887854

RESUMO

INTRODUCTION: Studies examining the relationship between stress secondary to adverse life events (ALE) and inflammatory bowel disease (IBD) have produced controversial data. The aim of this study was to explore the subjective perception of this relationship in IBD patients. PATIENTS AND METHODS: Seventy consecutive patients suffering from IBD (40 Crohn's disease, 30 ulcerative colitis) were assessed using a self-rating questionnaire related to demographic variables, clinical characteristics, subjective perception of the influence of ALE on the course of IBD, psychiatric background, and the HAD scale. The results of this scale were compared with a group of 25 relatives. RESULTS: Forty-two patients (60%) perceived that there was relationship between ALE and the onset of their disease, forty-nine (70%) between ALE and the increasing IBD symptoms severity, and fifty-one patients (72.9%) with disease activity. Sixteen of the patients (22.9%) had been visited by a psychiatrist during relapses of IBD. Twenty-five patients (42.4%) reached a score of 11 or higher on the depression or anxiety subscales of the HAD, indicating a probable psychological disorder. CONCLUSIONS: IBD patients perceive a strong relationship between ALE and the course of IBD. We have found a high prevalence of anxiety and depression symptoms in these patients. If this observation is confirmed with objective measurements, it will be important to consider psychiatric intervention for these patients.


Assuntos
Doenças Inflamatórias Intestinais/complicações , Doenças Inflamatórias Intestinais/psicologia , Estresse Fisiológico , Atividades Cotidianas , Adulto , Ansiedade/complicações , Ansiedade/epidemiologia , Depressão/complicações , Depressão/epidemiologia , Feminino , Humanos , Doenças Inflamatórias Intestinais/epidemiologia , Masculino , Prevalência , Qualidade de Vida , Índice de Gravidade de Doença , Inquéritos e Questionários
12.
Rev Esp Quimioter ; 15(3): 247-56, 2002 Sep.
Artigo em Espanhol | MEDLINE | ID: mdl-12582428

RESUMO

The aims of this study were twofold: i) to evaluate the sustained response rate at 6 months, at 12 months and at the end of the follow-up [(46.39 +/- 9.74 months) (range: 6-60 months)] in patients with chronic hepatitis C retreated with interferon-a (IFN-a) plus ribavirin for 6 months (group A), 12 months (group B), in patients with relapse and those with no response to a previous course of monotherapy with IFN-a; and ii) to evaluate changes in the histological liver lesion. One hundred and four patients (100 with genotype 1 and four without), 44 with relapse and 60 non-responders, were included. A total of 20.2% of the patients were excluded because of side effects. Fifty percent of the relapsing patients with genotype 1 showed a sustained response. The sustained response rate was higher in group B than in group A, whereas the rate for the relapsing patients was lower in group B than in group A (13/20 vs. 5/16; 7.2% vs. 61.5%; p <0.09 and p <0.009, respectively). However, 9.3% of the non-responding patients showed a sustained response (A/B: 2/2). The relapsing patients who had a genotype other than 1 showed a sustained response. The sustained response rate was constant throughout the follow-up, except in relapsing patients from group A (the late relapse rate was 28.6%). The viral load was not related to the response. The grade and stage of the histological lesion improved in patients with sustained response (n=20) and in one-third of the non-responding patients (n=45) (p <0.0001 and p <0.0001). IFN in combination with ribavirin was more effective in relapsing patients with genotype 1 at 12 months than in those at 6 months of treatment, whereas the effectiveness in non-responding patients was low. The sustained response evaluation at 6 months was reliable, except in relapsing patients with 6 months of treatment. The histological lesion improved significantly with combination antiviral therapy.


Assuntos
Antivirais/uso terapêutico , Hepatite C Crônica/tratamento farmacológico , Interferon-alfa/uso terapêutico , Ribavirina/uso terapêutico , Adulto , Quimioterapia Combinada , Feminino , Seguimentos , Genótipo , Hepatite C Crônica/genética , Humanos , Interferon alfa-2 , Masculino , Estudos Prospectivos , Proteínas Recombinantes , Recidiva , Fatores de Tempo
13.
J Med Chem ; 44(22): 3599-605, 2001 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-11606124

RESUMO

The novel anticancer compound T138067 is an irreversible inhibitor of tubulin polymerization. Amides 3-6 were synthesized using standard methodologies and determined to be significantly less lipophilic than T138067 based on logP calculations. Tubulin polymerization and [(3)H]-T138067 competition assays revealed that these amides are pro-drugs for parent aniline 2. Amides 3-5 showed no detectable signs of crossing the blood brain barrier, while amide 6 was found in extremely small amounts (12 ng/g of brain tissue). Aniline 2, which was formed in vivo from these amides, was found in significantly smaller amounts (approximately 20 to >5000 times) in the brain than when 2 was administered directly. The in vivo efficacy of amide 6 approached that of T138067 and was better tolerated when administered to athymic nude mice bearing MX-1 human mammary tumor xenografts.


Assuntos
Compostos de Anilina/síntese química , Antineoplásicos/síntese química , Barreira Hematoencefálica , Sulfonamidas/química , Compostos de Anilina/química , Compostos de Anilina/farmacologia , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Encéfalo/metabolismo , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Masculino , Camundongos , Camundongos Nus , Polímeros , Relação Estrutura-Atividade , Transplante Heterólogo , Tubulina (Proteína)/química , Células Tumorais Cultivadas
14.
Pharm Acta Helv ; 74(2-3): 141-8, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10812951

RESUMO

The five muscarinic receptor subtypes (M1-M5) are characterized by seven helices that define a transmembrane cavity which serves as the binding pocket for agonists and antagonists. The five cavities appear to be topographically different enough to permit subtype selectivity among antagonists but not among classical agonists which tend to be smaller in size than antagonists. It was reasoned that synthesis of muscarinic agonists longer/larger than their classical counterparts might result in subtype selectivity. M1 subtype selectivity was found in a class of 1-azabicyclo[2.2.1]heptan-3-one, O-(3-aryl-2-propynyl) oximes. One of these, CI-1017, improved spatial memory of hippocampally deficient mice and nbM-lesioned rats at doses of 1.0-3.2 and 0.1-0.3 mg/kg, respectively, while producing parasympathetic side effects only at very high doses (100-178 mg/kg). Additionally, CI-1017 inhibited production of amyloidogenic A beta and increased secretion of soluble APP. Thus, CI-1017, besides treating AD symptomatically, may also retard its progression. CI-1017 has recently completed phase I clinical trials.


Assuntos
Compostos Bicíclicos Heterocíclicos com Pontes/síntese química , Compostos Bicíclicos Heterocíclicos com Pontes/farmacologia , Agonistas Muscarínicos/síntese química , Agonistas Muscarínicos/farmacologia , Oximas/síntese química , Oximas/farmacologia , Receptores Muscarínicos/efeitos dos fármacos , Animais , Clonagem Molecular , Humanos , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Memória/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C57BL , Ratos , Receptor Muscarínico M1 , Receptores Muscarínicos/metabolismo , Sistemas do Segundo Mensageiro/efeitos dos fármacos
15.
Acta Otorrinolaringol Esp ; 50(4): 316-20, 1999 May.
Artigo em Espanhol | MEDLINE | ID: mdl-10431082

RESUMO

Meningiomas are the most frequent benign intracranial tumor. Up to 20% of these neoplasms may eventually extend beyond the skull, particularly when tumor spread affects the temporal bone. We report a clinicopathological observation of an extracranial meningothelial meningioma that was diagnosed morphologically using immunohistochemical techniques. The tumor presented as polyp in the ear canal of a 70-year-old woman who had a history of ear disease and seizures and was under medical treatment. The growth was associated with a right temporal lobe tumor involving the petrosal bone that had been detected 6 years earlier on computed axial tomography.


Assuntos
Meato Acústico Externo/diagnóstico por imagem , Meato Acústico Externo/patologia , Neoplasias da Orelha/diagnóstico por imagem , Neoplasias da Orelha/patologia , Neoplasias Meníngeas/diagnóstico por imagem , Neoplasias Meníngeas/patologia , Meningioma/diagnóstico por imagem , Pólipos/diagnóstico por imagem , Pólipos/patologia , Idoso , Diagnóstico Diferencial , Feminino , Humanos , Imuno-Histoquímica , Tomografia Computadorizada por Raios X
16.
J Biol Chem ; 274(32): 22805-12, 1999 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-10428865

RESUMO

We describe a permanent line of Chinese hamster ovary cells transfected with a cDNA encoding a truncated form of Site-1 protease (S1P) that is secreted into the culture medium in an enzymatically active form. S1P, a subtilisin-like protease, normally cleaves the luminal loop of sterol regulatory element-binding proteins (SREBPs). This cleavage initiates the two-step proteolytic process by which the NH(2)-terminal domains of SREBPs are released from cell membranes for translocation to the nucleus, where they activate transcription of genes involved in the biosynthesis and uptake of cholesterol and fatty acids. Truncated S1P (amino acids 1-983), produced by the transfected Chinese hamster ovary cells, lacks the COOH-terminal membrane anchor. Like native S1P, this truncated protein undergoes normal autocatalytic processing after residue 137 to release an NH(2)-terminal propeptide, thereby generating an active form, designated S1P-B. Prior to secretion, truncated S1P-B, like native S1P-B, is cleaved further after residue 186 to generate S1P-C, which is the only form that appears in the culture medium. The secreted enzyme, designated S1P(983)-C, cleaves a synthetic peptide that terminates in a 7-amino-4-methyl-coumarin fluorochrome. This peptide, RSLK-MCA, corresponds to the internal propeptide cleavage site that generates S1P-B as described in the accompanying paper (Espenshade, P. J., Cheng, D., Goldstein, J. L., and Brown, M. S. (1999), J. Biol. Chem. 274, 22795-22804). The secreted enzyme does not cleave RSVL-MCA, a peptide corresponding to the physiologic cleavage site in SREBP-2. However, S1P(983)-C does cleave after this leucine when the RSVL sequence is contained within a 16-residue peptide corresponding to the central portion of the SREBP-2 luminal loop. The catalytic activity of S1P(983)-C differs from that of furin/prohormone convertases, two related proteases, in its more alkaline pH optimum (pH 7-8), its relative resistance to calcium chelating agents, and its ability to cleave after lysine or leucine rather than arginine. These data provide direct biochemical evidence that S1P is the protease that cleaves SREBPs and thereby functions to control lipid biosynthesis and uptake in animal cells.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Fragmentos de Peptídeos/metabolismo , Pró-Proteína Convertases , Serina Endopeptidases/metabolismo , Fatores de Transcrição/metabolismo , Sequência de Aminoácidos , Animais , Colesterol/farmacologia , Cricetinae , Proteínas de Ligação a DNA/genética , Hidroxicolesteróis/farmacologia , Dados de Sequência Molecular , Fragmentos de Peptídeos/genética , Inibidores de Proteases/farmacologia , Processamento de Proteína Pós-Traducional/efeitos dos fármacos , Proteínas Recombinantes/metabolismo , Serina Endopeptidases/genética , Proteína de Ligação a Elemento Regulador de Esterol 2 , Especificidade por Substrato , Fatores de Transcrição/genética
17.
Bioorg Med Chem Lett ; 9(13): 1843-6, 1999 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-10406652

RESUMO

In this report, we describe the synthesis of halogenated benzenesulfonamide compounds and their ability to inhibit the growth of HeLa, MCF-7 and MCF-7/ADR tumor cells in vitro. The multidrug resistance (MDR) phenotype of certain cells does not affect their sensitivity to these compounds. These agents belong to a family of compounds previously shown to bind irreversibly to cysteine-239 of beta-tubulin. Consistent with this mechanism of action, the cytotoxicities of these compounds appear to correlate with their ability to undergo nucleophilic aromatic substitution.


Assuntos
Sulfonamidas/síntese química , Resistência a Múltiplos Medicamentos , Inibidores do Crescimento/síntese química , Inibidores do Crescimento/farmacologia , Halogênios/química , Células HeLa , Humanos , Sulfonamidas/farmacologia , Células Tumorais Cultivadas
18.
Proc Natl Acad Sci U S A ; 96(10): 5686-91, 1999 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-10318945

RESUMO

Microtubules are linear polymers of alpha- and beta-tubulin heterodimers and are the major constituents of mitotic spindles, which are essential for the separation of chromosomes during mitosis. Here we describe a synthetic compound, 2-fluoro-1-methoxy-4-pentafluorophenylsulfonamidobenzene (T138067), which covalently and selectively modifies the beta1, beta2, and beta4 isotypes of beta-tubulin at a conserved cysteine residue, thereby disrupting microtubule polymerization. Cells exposed to T138067 become altered in shape, indicating a collapse of the cytoskeleton, and show an increase in chromosomal ploidy. Subsequently, these cells undergo apoptosis. Furthermore, T138067 exhibits cytotoxicity against tumor cell lines that exhibit substantial resistance to vinblastine, paclitaxel, doxorubicin, and actinomycin D. T138067 is also equally efficacious in inhibiting the growth of sensitive and multidrug-resistant human tumor xenografts in athymic nude mice. These observations suggest that T138067 may be clinically useful for the treatment of multidrug-resistant tumors.


Assuntos
Antineoplásicos/farmacologia , Cisteína/química , Sulfonamidas/farmacologia , Tubulina (Proteína)/química , Animais , Apoptose/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Citoesqueleto/efeitos dos fármacos , Resistência a Múltiplos Medicamentos , Humanos , Leucemia Linfoide/tratamento farmacológico , Camundongos , Camundongos Nus , Microtúbulos/metabolismo , Estrutura Molecular , Transplante de Neoplasias , Paclitaxel/farmacologia , Ligação Proteica , Sulfonamidas/síntese química , Células Tumorais Cultivadas , Vimblastina/farmacologia
19.
Bioorg Med Chem Lett ; 9(6): 815-20, 1999 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-10206542

RESUMO

A series of 2-sulfonyl-4H-3,1-benzoxazinones was prepared that inhibit C1r protease in vitro. Several compounds were found to be selective for C1r verses the related serine protease trypsin. Selected compounds demonstrated functional activity in a hemolysis assay.


Assuntos
Proteínas Inativadoras do Complemento 1/síntese química , Sulfonamidas/síntese química , Animais , Complemento C1r/antagonistas & inibidores , Eritrócitos/efeitos dos fármacos , Concentração Inibidora 50 , Cinética , Modelos Químicos , Ovinos , Benzenossulfonamidas
20.
J Med Chem ; 42(3): 356-63, 1999 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-9986705

RESUMO

A series of esters of 1,4-disubstituted tetrahydropyridine carboxylic acids (I) has been synthesized and characterized as potential m1 selective muscarinic receptor antagonists. The affinity of these compounds for the five human muscarinic receptor subtypes (Hm1-Hm5) was determined by the displacement of [3H]-NMS binding using membranes from transfected Chinese hamster ovarian cells. One of the most potent and selective compounds of this series is an analogue of I [11, R1 = (CH2)5CH3], which has an IC50 value of 27.3 nM at the m1 receptor and possesses 100-fold (m2), 48-fold (m3), 74-fold (m4), and 19-fold (m5) selectivities at the other receptors. Thus, this analogue appears to be more selective on the basis of binding than the prototypical m1 antagonist, pirenzepine. Functional data, such as the inhibition of carbachol-stimulated phosphatidylinositol hydrolysis, on selected analogues confirmed the muscarinic antagonistic properties of this chemical series.


Assuntos
Antagonistas Muscarínicos/química , Animais , Células CHO , Cricetinae , Humanos , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Estrutura Molecular , Antagonistas Muscarínicos/classificação , Antagonistas Muscarínicos/farmacologia , Relação Estrutura-Atividade
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