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1.
Clin Exp Dermatol ; 44(5): e177-e180, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30593710

RESUMO

The clinical characteristics associated with hidradenitis suppurativa (HS) severity are poorly understood. In this study, 124 patients with HS from 6 Italian dermatology centres participated in this study. Disease severity was assessed using the Hidradenitis Suppurativa Physician's Global Assessment score (HS-PGA) and Hurley score. The impact of clinical characteristics on disease severity was assessed by logistic regression. Clinical characteristics were similar between men (n = 53) and women (n = 71). Disease severity was also similar; 75% of the patients had Hurley stage II or III disease, and > 60% had moderate, severe or very severe HS as judged by HS-PGA. Lesions were more frequent in the gluteal region in men (32.3% in men vs. 8.7% in women, P < 0.001) and more frequent on the breast in women (16.3% in women vs. 4.6% in men, P = 0.02). Obesity was associated with increased disease severity as measured by HS-PGA (OR: 3.28, 95% CI 1.55-6.95, P < 0.01) and Hurley classification (OR: 3.22, 95% CI 1.34-7.31, P < 0.01). Although severity of HS is similar between the sexes, the localization of lesions is different.


Assuntos
Hidradenite Supurativa/fisiopatologia , Adulto , Axila , Mama , Nádegas , Comorbidade , Feminino , Virilha , Hidradenite Supurativa/epidemiologia , Humanos , Itália/epidemiologia , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Obesidade/epidemiologia , Índice de Gravidade de Doença , Fatores Sexuais , Adulto Jovem
3.
Clin Genet ; 93(5): 1039-1048, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29266212

RESUMO

Clinical exome sequencing (CES) is increasingly being used as an effective diagnostic tool in the field of pediatric genetics. We sought to evaluate the parental experience, understanding and psychological impact of CES by conducting a survey study of English-speaking parents of children who had diagnostic CES. Parents of 192 unique patients participated. The parent's interpretation of the child's result agreed with the clinician's interpretation in 79% of cases, with more frequent discordance when the clinician's interpretation was uncertain. The majority (79%) reported no regret with the decision to have CES. Most (65%) reported complete satisfaction with the genetic counseling experience, and satisfaction was positively associated with years of genetic counselor (GC) experience. The psychological impact of CES was greatest for parents of children with positive results and for parents with anxiety or depression. The results of this study are important for helping clinicians to prepare families for the possible results and variable psychological impact of CES. The frequency of parental misinterpretation of test results indicates the need for additional clarity in the communication of results. Finally, while the majority of patients were satisfied with their genetic counseling, satisfaction was lower for new GCs, suggesting a need for targeted GC training for genomic testing.


Assuntos
Deficiências do Desenvolvimento/genética , Sequenciamento do Exoma/métodos , Exoma/genética , Aconselhamento Genético , Adulto , Criança , Deficiências do Desenvolvimento/fisiopatologia , Revelação , Feminino , Testes Genéticos , Humanos , Masculino , Pais , Inquéritos e Questionários
4.
J Biol Regul Homeost Agents ; 32(2): 407-413, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29685026

RESUMO

Articular pain is one of the most frequent complaints practitioners face in their daily work. With an aging population, many patients have multiple comorbidities that are associated with the presence of chronic diseases, while others experience allergies, side effects or do not respond to standard medications or procedures. Therefore, there is an urgent need for new effective and safe strategies to manage articular pain, especially in its chronic manifestations. This randomized controlled trial was designed to assess the efficacy of a single therapy session using a biophysical procedure matched with a common non-steroidal anti-inflammatory drug (ibuprofen) and placebo. Biophysical therapy was performed using a Med Select 729 device. One hundred fifty patients (mean age 56±15.6 years) diagnosed with acute or chronic articular pain at different locations were randomized into 3 groups and the Numeric Pain Rating Score (NPRS) was used to measure pain at baseline, after one week, one month, and three months. While no difference in NPRS was observed at baseline among the 3 groups, a statistically significant difference was observed at all subsequent time points, respectively, after one week (p less than 0.05), one month (p less than 0.001), and three months (p less than 0.01), for both ibuprofen and biophysical groups vs placebo. Biophysical treatment of articular pain was shown to be as effective as a conventional non-steroidal anti-inflammatory treatment over a period of 3 months compared to placebo and could, therefore, represent an integrative, safe and long-lasting therapy to be considered for the management of acute and particularly chronic articular pain in current medical practice.


Assuntos
Analgésicos não Narcóticos/uso terapêutico , Artralgia/terapia , Terapia por Estimulação Elétrica/métodos , Ibuprofeno/uso terapêutico , Adulto , Idoso , Anti-Inflamatórios não Esteroides/uso terapêutico , Método Duplo-Cego , Radiação Eletromagnética , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
5.
J Eur Acad Dermatol Venereol ; 32(10): 1737-1744, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29776016

RESUMO

BACKGROUND: Few studies have compared the efficacy of switching to adalimumab in the real-life setting in plaque psoriasis patients. OBJECTIVE: To evaluate the effect of adalimumab in psoriasis patients previously treated with other biologics. METHODS: In this multicentre study, psoriasis patients (N = 262) treated with an anti-TNF-alpha agent, ustekinumab or naïve to biologics then switched to adalimumab were included. Disease severity was assessed by the Psoriasis Area and Severity Index (PASI) at baseline and after 3, 6, 12, 24 and 36 months. The association between clinical risk factors and achievement of PASI response was evaluated by logistic regression. RESULTS: Adalimumab treatment resulted in a decrease in PASI (15.1 ± 6.2 at baseline vs. 2.7 ± 4.8 at 6 months, P < 0.0001), regardless of previous biologic treatment. Furthermore, adalimumab allowed 92.5%, 79% and 56% of patients to achieve PASI response (PASI 50, 75 and 90, respectively) and complete remission (PASI 100 response) in 48.4% of patients, by 6 months and maintained over 3 years, independent of prior biologic treatment. The absence of metabolic syndrome, dyslipidemia, hypertension and lower PASI and lower age at baseline was associated with achievement of PASI response at 3, 6 and 12 months, whereas at later time points (24 and 36 months), PASI 90 and PASI 100 response was associated with diagnosis of psoriasis/psoriatic arthritis. CONCLUSION: Adalimumab was effective at reducing PASI score over 3 years, irrespective of whether patients were biologic naïve or previously treated with a TNF-alpha or IL-12/23 inhibitor.


Assuntos
Adalimumab/uso terapêutico , Fármacos Dermatológicos/uso terapêutico , Psoríase/tratamento farmacológico , Adulto , Fatores Etários , Idoso , Anticorpos Monoclonais/uso terapêutico , Substituição de Medicamentos , Dislipidemias/complicações , Etanercepte/uso terapêutico , Feminino , Humanos , Hipertensão/complicações , Infliximab/uso terapêutico , Estudos Longitudinais , Masculino , Síndrome Metabólica/complicações , Pessoa de Meia-Idade , Psoríase/complicações , Estudos Retrospectivos , Índice de Gravidade de Doença , Fatores de Tempo , Ustekinumab/uso terapêutico
7.
Skin Res Technol ; 22(3): 341-8, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26450445

RESUMO

BACKGROUND AND PURPOSE: Effective non-invasive techniques to monitor plaque psoriasis progression and treatment are desirable. The aim of the study was to evaluate changes in vascular pattern using videodermatoscopy (VD) and in skin thickness by ultrasound (US), along with clinical observation, during treatment with biologicals. METHODS: Forty-two patients with moderate-to-severe plaque psoriasis treated with adalimumab, etanercept, or ustekinumab were evaluated. Following the identification of a 'target' plaque at baseline, lesion changes were monitored at 15, 30 and 60 days by clinical observation using a Target Lesion Score (TLS), and by VD and US. RESULTS: After 60 days, a significant improvement in all three parameters was observed. In adalimumab-treated patients mean values of TLS, VD, and US were reduced by 83.9%, 73.5%, and 90%, respectively; in etanercept-treated patients by 67.9%, 49.7%, and 79.3%; in ustekinumab-treated patients by 80.9%, 66.4%, and 80.1%. Skin thickness was the first parameter to improve. Vascular improvement was slower compared to clinical and US responses. CONCLUSION: VD and US may be useful to monitor psoriasis treatment. Further investigations are warranted to assess if the persistence of an altered vascular pattern despite clinical and US normalization, as observed in 22% of patients, may influence disease progression and/or correlate with rate and severity degree of relapse.


Assuntos
Produtos Biológicos/administração & dosagem , Dermoscopia/métodos , Monitoramento de Medicamentos/métodos , Psoríase/diagnóstico por imagem , Psoríase/tratamento farmacológico , Ultrassonografia/métodos , Adulto , Anti-Inflamatórios/administração & dosagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Exame Físico/métodos , Psoríase/patologia , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Resultado do Tratamento , Gravação em Vídeo/métodos
8.
Ir Med J ; 108(4): 120-1, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26016306

RESUMO

Richter's transformation of chronic lymphocytic leukaemia (CLL) to high-grade B-cell Non-Hodgkin lymphoma occurs in < 5% of CLL cases. Transformation of CLL to Hodgkin Lymphoma is a much rarer event and here we describe a patient who developed Richter's transformation into a Hodgkin Lymphoma presenting as rapidly progressive hepatosplenomegaly.


Assuntos
Transformação Celular Neoplásica , Doença de Hodgkin/patologia , Leucemia Linfocítica Crônica de Células B/patologia , Idoso , Hepatomegalia/etiologia , Humanos , Masculino , Esplenomegalia/etiologia
11.
J Endocrinol Invest ; 36(8): 606-16, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23511244

RESUMO

BACKGROUND: Previous evidence indicates that pioglitazone may improve dyslipidemia in patients with Type 2 diabetes mellitus (T2DM). AIM: The primary objective of this study was to evaluate the effect of either pioglitazone or placebo with metformin on levels of serum HDL cholesterol (HDL-C) in patients with T2DM. A secondary objective evaluated changes in metabolic syndrome (MS)-specific parameters. SUBJECTS AND METHODS: This multicenter, double-blind, randomized study was performed in patients with T2DM treated with metformin and hemoglobin A1c (HbA1c) levels between 6-8%, central obesity and reduced HDL-C. MS was evaluated from global changes in parameter values and expressed as a single factorial score following multivariate analysis of each parameter. 213 patients (110 in the pioglitazone group and 103 in the placebo group) were available for intention-to-treat analysis. RESULTS: Pioglitazone-treated patients showed a significant increase in HDL-C compared to placebo group (6.3 mg/dl vs 3.0 mg/dl; p<0.01) in addition to a greater reduction in the extent of MS (-13.2 vs -4.9; p=0.0055). Upon study completion, patients treated with pioglitazone had lower levels of HbA1c (6.41±0.65 vs 6.96±0.74%; p<0.001) and homeostasis model assessment-insulin resistance (HOMA-IR) (2.88±1.95 vs 4.68±3.63; p=0.013) and a reduction of the atherogenic LDL subfraction (pattern B) (-5.7%). CONCLUSIONS: The beneficial effects observed in pioglitazone-treated patients in the present study, (i.e. the increase in HDL-C and the reduction of insulin resistance and atherogenic LDL subfractions), support findings from the PROactive trial, where pioglitazone showed pleiotropic effects and reduced death, fatal myocardial infarction (MI) and non-fatal MI in T2DM patients with MS. Furthermore, medication used in this study showed good tolerability.


Assuntos
HDL-Colesterol/sangue , Diabetes Mellitus Tipo 2/tratamento farmacológico , Síndrome Metabólica/tratamento farmacológico , Metformina/administração & dosagem , Tiazolidinedionas/administração & dosagem , Adulto , Idoso , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/metabolismo , Método Duplo-Cego , Combinação de Medicamentos , Feminino , Hemoglobinas Glicadas/metabolismo , Homeostase , Humanos , Resistência à Insulina , Masculino , Síndrome Metabólica/metabolismo , Pessoa de Meia-Idade , Modelos Biológicos , Pioglitazona , Placebos
12.
Breast Cancer Res Treat ; 133(1): 201-14, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-21894461

RESUMO

The preferential metastasis of breast cancer cells to bone comprises a complex set of events including homing and preferential growth, which may require unique factors produced by bone or other cells in the immediate microenvironment. In this study, an in vitro co-culture system composed of bone mesenchymal stem cells and breast cancer cell lines is used to examine the role of Src kinase on breast cancer cell migration and invasion in the presence of bone-derived cells. This research shows that Src kinase activity in breast cancer cell lines with either high or low levels of endogenous Src activity is increased by bone-derived cell-conditioned medium but not HS68 fibroblast-conditioned medium. Breast cancer cells exhibit enhanced migration in co-culture with bone-derived cells but not HS68 fibroblasts or no co-cultured cells. Inhibition of Src kinase activity using the inhibitors PP2 or saracatinib or using siRNA abrogates the preferential migration of the breast cancer cell lines in response to bone-derived cells. Inhibition of Src activity with saracatinib does not have any significant effect on breast cancer cell invasion in the presence of bone-derived cells. Factors are identified that are produced preferentially by bone-derived cells over HS68 cells that may impact breast cancer cell behavior. This research implicates Src kinase as an important effector of bone-derived cell signals on breast cancer cell migration.


Assuntos
Neoplasias Ósseas/secundário , Neoplasias da Mama/patologia , Quinases da Família src/fisiologia , Benzodioxóis/farmacologia , Neoplasias Ósseas/enzimologia , Osso e Ossos/patologia , Neoplasias da Mama/enzimologia , Linhagem Celular Tumoral , Movimento Celular , Técnicas de Cocultura , Meios de Cultivo Condicionados , Ativação Enzimática , Feminino , Perfilação da Expressão Gênica , Humanos , Masculino , Células-Tronco Mesenquimais/patologia , Invasividade Neoplásica , Análise de Sequência com Séries de Oligonucleotídeos , Fosforilação , Processamento de Proteína Pós-Traducional , Quinazolinas/farmacologia , Microambiente Tumoral , Quinases da Família src/antagonistas & inibidores , Quinases da Família src/metabolismo
13.
Anaesthesia ; 67(12): 1356-63, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23061397

RESUMO

We investigated block heights that anaesthetists considered adequate for caesarean section to proceed under spinal anaesthesia. During 3 months, 15 obstetric anaesthetists recorded block height to touch, pinprick or cold when spinal anaesthesia was considered satisfactory for caesarean section to proceed. Median (IQR [range]) block height for touch, pinprick, first cold and icy were: T10 (T7-T12 [T3-L1]); T5 (T4-T6 [C7-L1]); T5 (T4-T6 [C7-L1]); and T3 (T2-T4 [C7-L1]), respectively. Modalities were significantly correlated for: touch and cold, p = 0.0001; touch and icy, p = 0.0007; touch and pinprick, p = 0.0018; cold and icy, p < 0.0001; cold and pinprick, p = 0.0001; icy and pinprick, p < 0.0001. Pairwise comparisons showed differences between all modalities (p < 0.001) apart from pinprick and first cold (p = 0.94). All women had satisfactory anaesthesia despite 76 (81%) having a block to touch below T6. Single modality assessment of block height, particularly using touch, may erroneously indicate inadequate anaesthesia for caesarean section.


Assuntos
Anestesia Obstétrica/métodos , Raquianestesia/métodos , Cesárea , Satisfação do Paciente , Sensação/efeitos dos fármacos , Adulto , Analgésicos Opioides/administração & dosagem , Anestésicos Locais/administração & dosagem , Austrália , Bupivacaína/administração & dosagem , Temperatura Baixa , Relação Dose-Resposta a Droga , Feminino , Fentanila/administração & dosagem , Humanos , Pessoa de Meia-Idade , Morfina/administração & dosagem , Medição da Dor/efeitos dos fármacos , Gravidez , Tato/efeitos dos fármacos , Adulto Jovem
15.
Anaesthesia ; 66(7): 550-5, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21564041

RESUMO

We hypothesised that in obese patients, tracheal intubation with the GlideScope® would be advantageous compared with flexible fibreoptic intubation. Seventy-five anaesthetised obese patients were randomly assigned to oral intubation by either GlideScope or flexible fibreoptic bronchoscope. We compared the two devices for time to intubate (p = 0.19), difficulty of intubation (p = 0.58), successful intubation on first attempt (p = 0.29), number of attempts (p = 0.24), incidence of hypoxaemia (p = 0.57), amount of post-intubation bleeding (p = 0.79) and sore throat (p = 0.82). None differed significantly. Median (IQR [range]) time to intubation was 37 (25-48 [19-81]) s and 95% of the first attempts were successful with the GlideScope, vs 43 (35-58 [26-96]) s and an 86% first-attempt success rate with the flexible fibreoptic bronchoscope. For experienced users, the time required to intubate the trachea in anaesthetised obese patients is similar with the GlideScope and a flexible bronchoscope.


Assuntos
Intubação Intratraqueal/instrumentação , Laringoscópios , Obesidade/complicações , Adulto , Idoso , Anestesia Geral , Broncoscópios/efeitos adversos , Feminino , Tecnologia de Fibra Óptica/instrumentação , Humanos , Intubação Intratraqueal/efeitos adversos , Intubação Intratraqueal/métodos , Estimativa de Kaplan-Meier , Laringoscópios/efeitos adversos , Masculino , Pessoa de Meia-Idade , Faringite/etiologia , Fatores de Tempo , Gravação em Vídeo/instrumentação , Adulto Jovem
16.
Sex Transm Infect ; 86(3): 247-50, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20237395

RESUMO

OBJECTIVES: To study the demographics, risk behaviours and morbidity of young long-term international travellers (backpackers) attending a sexual health service in Sydney, Australia. METHODS: Data on new patients were extracted from the Sydney Sexual Health Centre database for the period 1998 to 2006. The sexual risk behaviours and morbidity of the backpackers were compared with other patients of a similar age. RESULTS: The 5698 backpackers who attended the centre reported higher numbers of sexual partners (three or more partners in the past 3 months, 18% vs 12%, p<0.001) and a greater proportion drank alcohol at hazardous levels (22%) than the comparison group (9%, p<0.001). Rates of consistent (100%) condom use in the past 3 months were low in both backpackers (22%) and the comparison population (19%). Backpackers had higher rates of genital chlamydia infection (7% vs 5%, p<0.001) and reported higher rates of previous sexually transmitted infections (15% vs 10%, p<0.001). CONCLUSIONS: Backpackers should be a priority population for sexual health promotion and access to services.


Assuntos
Infecções Sexualmente Transmissíveis/epidemiologia , Migrantes/estatística & dados numéricos , Sexo sem Proteção/estatística & dados numéricos , Adulto , Estudos de Casos e Controles , Preservativos/estatística & dados numéricos , Feminino , Humanos , Masculino , New South Wales/epidemiologia , Parceiros Sexuais , Adulto Jovem
17.
Int J Immunopathol Pharmacol ; 23(4): 1177-83, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-21244766

RESUMO

For the past 25 years, cyclosporine A (CyA) has played a pivotal role in transplant immunosuppressant therapy. From the availability of the 2 primary marketed formulations (Sandimmun® and Sandimmun Neoral®, Novartis), confusion has existed with regard to whether these two formulations are bioequivalent. Due to the underlying clinical relevance of this information, we therefore conducted a meta-analysis of all available comparative pharmacokinetic studies to assess whether the two different CyA formulations, Sandimmun® and Sandimmun Neoral®, can be considered bioequivalent. All clinical studies that compared the bioavailability of the 2 formulations in organ transplant recipients were considered for analysis. We searched computerised databases (Embase/Excerpta Medica and Medline/PubMed) from their inception to May 2010. Only studies with AUC values determined at 12 hours were considered for analysis. Relative bioavailability was calculated with 90 percent confidence intervals (CI) for Sandimmun® (test substance) versus Sandimmun Neoral® (reference substance) according to Schuirmann?s Two One-Sided Tests Procedure and the Classical Shortest CI. Homogeneity of data was tested using the Χ(2) test. Fifteen studies were considered for meta-analysis and none of these studies reported AUC values in the 80-125 percent range required for the bioequivalence of two formulations. The overall bioavailability for Sandimmun® versus the microemulsion formulation Sandimmun Neoral® was 76 percent, with upper CI limits lower than 80 percent in some cases. Mean AUC values for Sandimmun® were significantly lower than those for Sandimmun Neoral® (p<0.01). This study demonstrates that the 2 main cyclosporine formulations, Sandimmun® and Sandimmun Neoral®, cannot be considered bioequivalent.


Assuntos
Ciclosporina/farmacocinética , Imunossupressores/farmacocinética , Área Sob a Curva , Disponibilidade Biológica , Química Farmacêutica , Ciclosporina/administração & dosagem , Humanos
18.
Expert Opin Biol Ther ; 20(1): 95-104, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31640431

RESUMO

Background: Limited information is available from real-life studies evaluating the long-term efficacy and drug retention of ustekinumab.Research design and methods: Data from 378 patients with moderate-severe psoriasis were retrospectively analyzed. Over 8 years, disease severity and treatment response were evaluated using the PASI score. Predictors of PASI response were evaluated by logistic regression. Ustekinumab retention rate was calculated by the Kaplan-Meier method.Results: Over the 8 years, >80% of patients achieved a PASI score of <3 and PASI 75, 90 and 100 response was achieved in 76.2%, 61.9% and 57.1% of patients, respectively. Predictor variables for improved PASI response (after 2 years) were HLA-C*06-POS patients, female gender and BMI <30 Kg/M2. The 2-year retention rate was 81% and 59% after 8 years with mean retention rate of 5.4 years. Improved retention rate was observed in patients positive for the HLA-C*06 allele (3.7 vs. 2.5 years, p = 0.005) and female gender (3.7 vs. 3.3 years, p = 0.06), with no significant difference observed in other patient groups. Ustekinumab was generally well tolerated without evidence of cumulative toxicity or organ toxicity.Conclusion: The long-term use of ustekinumab was observed to be effective and safe in patients with moderate-severe chronic psoriasis in a real world-setting.


Assuntos
Fármacos Dermatológicos/uso terapêutico , Psoríase/tratamento farmacológico , Ustekinumab/uso terapêutico , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Índice de Gravidade de Doença , Resultado do Tratamento
19.
Clin Exp Immunol ; 156(1): 17-24, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19161444

RESUMO

Toll-like receptor (TLR)/MyD88 signalling has emerged as a major pathway of pathogen recognition in the innate immune system. Here, we review recent data that begin to show how this pathway controls the immune response to protozoan infection, with particular emphasis on the opportunistic pathogen Toxoplasma gondii. The various ways that the parasite activates and suppresses TLR/MyD88 signalling defines several key principals that illuminate the complexities of the host-pathogen interaction. We also speculate how TLR/MyD88 signalling might be exploited to provide protection against Toxoplasma, as well as other protozoa and infection in general.


Assuntos
Receptores Toll-Like/imunologia , Toxoplasma/imunologia , Toxoplasmose/imunologia , Animais , Interações Hospedeiro-Parasita , Humanos , Imunidade Celular , Imunidade nas Mucosas , Ligantes , Transdução de Sinais/imunologia
20.
Oncogene ; 26(28): 4124-34, 2007 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-17213803

RESUMO

Reovirus shows considerable potential as an oncolytic agent for Ras-activated tumors and is currently in clinical trials. Here we ask whether such tumor cell lines can acquire resistance to reoviral oncolysis. We challenged human HT1080 fibrosarcoma cells that carry a Ras mutation by prolonged exposure to reovirus, thereby yielding highly virus-resistant HTR1 cells. These cells are persistently infected with reovirus, exhibit high Ras activity and retain the original Ras gene mutation, showing that resistance to reovirus can be displayed in cells with active Ras. The HTR1 cells also exhibit reduced cellular cathepsin B activity, which normally contributes to viral entry and activation. Persistently infected HTR1 cells were not tumorigenic in vivo, whereas immunologically cured virus-free HTR1 cells were highly tumorigenic. Thus, acquisition of resistance to reovirus may constrain therapeutic strategies. To determine whether reoviral resistance is associated with a general reduction in apoptotic potential, we challenged the HTR1 cells with apoptotic inducers and E1B-defective adenovirus, resulting in significant apoptosis and cell death following both approaches. Therefore, even if resistance to reoviral oncolysis should arise in tumor cells in vivo, other therapeutic strategies may nevertheless remain effective.


Assuntos
Fibrossarcoma/patologia , Proteína Oncogênica p21(ras)/fisiologia , Reoviridae/fisiologia , Sequência de Bases , Catepsina B/metabolismo , Linhagem Celular , Linhagem Celular Tumoral , Primers do DNA , Fibrossarcoma/virologia , Humanos , Mutação , Proteína Oncogênica p21(ras)/genética
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