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1.
Ir Med J ; 114(2): 277, 2021 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-36331959

RESUMO

Presentation A 60-year-old male taking etanercept for ankylosing spondylitis was admitted to hospital with confusion and reduced level of consciousness over the preceding 24 hours. Diagnosis Magnetic Resonance Imaging (MRI) of his brain revealed pyogenic ventriculitis, and Escherichia coli was cultured from CSF. Treatment He required placement of an external ventricular drain and was treated with a prolonged course of intravenous ceftriaxone. Conclusion To our knowledge, this is the first reported case of spontaneous Gram-negative bacillary meningitis in a patient on anti-tumour necrosis factor (TNF)-alpha therapy, highlighting the risk of rare but serious infections associated with this class of medication.

2.
J Cancer Surviv ; 14(1): 31-35, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31713100

RESUMO

PURPOSE: With a substantial increase in the population of cancer survivors of working age, issues concerning sustainable employment must be addressed. The health benefits of work are well established; however, the lack of support to transition back to work is a gap in survivorship care. Researchers, occupational rehabilitation and insurance sectors, cancer support services, and consumers have collaborated to develop a tailored, multimodal occupational rehabilitation program to support resumption of meaningful work for cancer survivors. This paper describes intervention development and refinement based on pilot results and expert- and consumer-recommendations. METHODS: The pilot was conducted within the life insurance sector, a collaboration fostered by global reinsurance company Swiss Re, with cancer survivors referred to an Australian provider of occupational rehabilitation services. RESULTS: Preliminary outcomes from 15 of 72 cancer survivors following adequate engagement (excluding those who withdrew or were still actively engaged) showed 10 (67%) with improved certified capacity to work, translating to 13 (87%) with improved work status. Consultant survey results indicated barriers to participation in and engagement with the program, including referral delays, health concerns, and cancer recurrence. Expert panel recommendations were used to refine the intervention and tailor to breast cancer survivors for the feasibility stage. CONCLUSIONS: Strengths include an innovative model of referral and funding, through a life insurance provider, the involvement of a multidisciplinary collaborative team to design, develop and implement the pilot, and considerable consumer involvement. IMPLICATIONS FOR CANCER SURVIVORS: The refined intervention will address a critical gap to improve reintegration into work and society, contributing to improved quality of life for cancer survivors in Australia. Models of referral through insurers to rehabilitation services could be adopted in other jurisdictions.


Assuntos
Neoplasias da Mama/reabilitação , Sobreviventes de Câncer/psicologia , Terapia Ocupacional/métodos , Qualidade de Vida/psicologia , Retorno ao Trabalho/tendências , Austrália , Neoplasias da Mama/mortalidade , Neoplasias da Mama/psicologia , Feminino , Humanos , Projetos Piloto
3.
J Immunother Cancer ; 7(1): 62, 2019 03 04.
Artigo em Inglês | MEDLINE | ID: mdl-30832732

RESUMO

BACKGROUND: Checkpoint blockade immunotherapy has improved metastatic cancer patient survival, but response rates remain low. There is an unmet need to identify mechanisms and tools to circumvent resistance. In human patients, responses to checkpoint blockade therapy correlate with tumor mutation load, and intrinsic resistance associates with pre-treatment signatures of epithelial mesenchymal transition (EMT), immunosuppression, macrophage chemotaxis and TGFß signaling. METHODS: To facilitate studies on mechanisms of squamous cell carcinoma (SCC) evasion of checkpoint blockade immunotherapy, we sought to develop a novel panel of murine syngeneic SCC lines reflecting the heterogeneity of human cancer and its responses to immunotherapy. We characterized six Kras-driven cutaneous SCC lines with a range of mutation loads. Following implantation into syngeneic FVB mice, we examined multiple tumor responses to α-PD-1, α-TGFß or combinatorial therapy, including tumor growth rate and regression, tumor immune cell composition, acquired tumor immunity, and the role of cytotoxic T cells and Tregs in immunotherapy responses. RESULTS: We show that α-PD-1 therapy is ineffective in establishing complete regression (CR) of tumors in all six SCC lines, but causes partial tumor growth inhibition of two lines with the highest mutations loads, CCK168 and CCK169. α-TGFß monotherapy results in 20% CR and 10% CR of established CCK168 and CCK169 tumors respectively, together with acquisition of long-term anti-tumor immunity. α-PD-1 synergizes with α-TGFß, increasing CR rates to 60% (CCK168) and 20% (CCK169). α-PD-1 therapy enhances CD4 + Treg/CD4 + Th ratios and increases tumor cell pSmad3 expression in CCK168 SCCs, whereas α-TGFß antibody administration attenuates these effects. We show that α-TGFß acts in part through suppressing immunosuppressive Tregs induced by α-PD-1, that limit the anti-tumor activity of α-PD-1 monotherapy. Additionally, in vitro and in vivo, α-TGFß acts directly on the tumor cell to attenuate EMT, to activate a program of gene expression that stimulates immuno-surveillance, including up regulation of genes encoding the tumor cell antigen presentation machinery. CONCLUSIONS: We show that α-PD-1 not only initiates a tumor rejection program, but can induce a competing TGFß-driven immuno-suppressive program. We identify new opportunities for α-PD-1/α-TGFß combinatorial treatment of SCCs especially those with a high mutation load, high CD4+ T cell content and pSmad3 signaling. Our data form the basis for clinical trial of α-TGFß/α-PD-1 combination therapy (NCT02947165).


Assuntos
Proteína Smad3/metabolismo , Linfócitos T Auxiliares-Indutores/imunologia , Linfócitos T Auxiliares-Indutores/metabolismo , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/metabolismo , Fator de Crescimento Transformador beta/antagonistas & inibidores , Antineoplásicos Imunológicos/farmacologia , Antineoplásicos Imunológicos/uso terapêutico , Biomarcadores , Contagem de Linfócito CD4 , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/etiologia , Carcinoma de Células Escamosas/metabolismo , Linhagem Celular Tumoral , Sinergismo Farmacológico , Transição Epitelial-Mesenquimal , Humanos , Imuno-Histoquímica , Contagem de Linfócitos , Linfócitos do Interstício Tumoral/imunologia , Linfócitos do Interstício Tumoral/metabolismo , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Receptor de Morte Celular Programada 1/metabolismo , Transdução de Sinais/efeitos dos fármacos , Linfócitos T Auxiliares-Indutores/efeitos dos fármacos , Linfócitos T Reguladores/efeitos dos fármacos
4.
Clin Microbiol Infect ; 24 Suppl 1: e1-e38, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29544767

RESUMO

The European Society for Clinical Microbiology and Infectious Diseases, the European Confederation of Medical Mycology and the European Respiratory Society Joint Clinical Guidelines focus on diagnosis and management of aspergillosis. Of the numerous recommendations, a few are summarized here. Chest computed tomography as well as bronchoscopy with bronchoalveolar lavage (BAL) in patients with suspicion of pulmonary invasive aspergillosis (IA) are strongly recommended. For diagnosis, direct microscopy, preferably using optical brighteners, histopathology and culture are strongly recommended. Serum and BAL galactomannan measures are recommended as markers for the diagnosis of IA. PCR should be considered in conjunction with other diagnostic tests. Pathogen identification to species complex level is strongly recommended for all clinically relevant Aspergillus isolates; antifungal susceptibility testing should be performed in patients with invasive disease in regions with resistance found in contemporary surveillance programmes. Isavuconazole and voriconazole are the preferred agents for first-line treatment of pulmonary IA, whereas liposomal amphotericin B is moderately supported. Combinations of antifungals as primary treatment options are not recommended. Therapeutic drug monitoring is strongly recommended for patients receiving posaconazole suspension or any form of voriconazole for IA treatment, and in refractory disease, where a personalized approach considering reversal of predisposing factors, switching drug class and surgical intervention is also strongly recommended. Primary prophylaxis with posaconazole is strongly recommended in patients with acute myelogenous leukaemia or myelodysplastic syndrome receiving induction chemotherapy. Secondary prophylaxis is strongly recommended in high-risk patients. We strongly recommend treatment duration based on clinical improvement, degree of immunosuppression and response on imaging.


Assuntos
Antifúngicos/uso terapêutico , Aspergilose/diagnóstico , Aspergilose/tratamento farmacológico , Aspergillus/isolamento & purificação , Gerenciamento Clínico , Anticorpos Antifúngicos/sangue , Antifúngicos/farmacologia , Aspergilose/complicações , Aspergilose/imunologia , Aspergillus/efeitos dos fármacos , Aspergillus/imunologia , Biópsia/métodos , Lavagem Broncoalveolar , Diagnóstico Precoce , Flucitosina/farmacologia , Flucitosina/uso terapêutico , Galactose/análogos & derivados , Humanos , Hospedeiro Imunocomprometido , Testes Imunológicos , Aspergilose Pulmonar Invasiva/diagnóstico , Itraconazol/farmacologia , Itraconazol/uso terapêutico , Leucemia Mieloide Aguda/complicações , Leucemia Mieloide Aguda/terapia , Imageamento por Ressonância Magnética , Mananas/análise , Testes de Sensibilidade Microbiana , Síndromes Mielodisplásicas/complicações , Síndromes Mielodisplásicas/terapia , Nitrilas/farmacologia , Nitrilas/uso terapêutico , Piridinas/farmacologia , Piridinas/uso terapêutico , Tomografia Computadorizada por Raios X , Triazóis/farmacologia , Triazóis/uso terapêutico , Voriconazol/farmacologia , Voriconazol/uso terapêutico
6.
Frontline Gastroenterol ; 6(2): 141-146, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28839801

RESUMO

OBJECTIVE: Investigate success rates of cannulating a 'virgin' papilla during endoscopic retrograde cholangiopancreatography (ERCP) at a tertiary referral centre; determine reasons for failure and propose learnings for consideration in future revision of success benchmarking. DESIGN: Review of all ERCPs recorded on Endosoft database from 2006 to 2012 (n=1862). Specifically, 'virgin' papillae, defined as those with no evidence of prior surgical intervention, stents in situ or sphincterotomy (n=947). Virgin papillae present the most challenging target for endoscopists. SETTING: Gastroenterology department, St Thomas' Hospital, London. PATIENTS: All patients who underwent an ERCP recorded on Endosoft from 2006 to 2012 (n=1134). A proportion of these patients underwent repeat procedures, all considered virgin provided the aforementioned criteria were met. INTERVENTIONS: None, retrospective audit and benchmarking exercise. MAIN OUTCOME MEASURES: Determine criteria for successful cannulation of a virgin papilla. RESULTS: Overall success of cannulation of a virgin papilla at ERCP was 79.5%, 753 out of a total of 947 virgin papillae cases. Per patient with a virgin papilla, the success rate was 79.7%, 693 out of 869. Eliminating cases with features complicating cannulation increased success rates to 86% and 87%, respectively. Chronic pancreatitis was the single Indication associated with a failed cannulation (OR=3.9, CI 2.1 to 7.1), while biliary stones were significantly associated with a successful cannulation (OR=0.3, CI 0.2 to 0.4). Reasons for failure included patient agitation (OR=27.1, CI 7.9 to 92.7), duodenal stricturing (OR=12.5, CI 5.5 to 28.5), previous anatomy-changing surgery (OR=12.2, CI 3.3 to 45.4), tumour impingement (OR=9.5, CI 4.1 to 22.3) and equipment failure (OR=7.9, CI 1.4=43.5). CONCLUSIONS: The Joint Advisory Group's 80% success rate for completion of therapeutic intent must be viewed in light of published difficulty rating scales, if fair comparisons and standards are to be met. This highlights the need for standardised success criterion for ERCP training and accreditation.

7.
Bone Marrow Transplant ; 49(6): 751-5, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24614838

RESUMO

Plerixafor effectively mobilizes hematopoietic stem cells (HSCs). However, most patients' cells are successfully collected using traditional strategies and there is limited cost-effectiveness data. The objectives of this study were to: (1) summarize the published reports of mobilization using a plerixafor-based strategy during compassionate access programs and (2) describe the Canadian experience with plerixafor during its availability by Health Canada's Special Access Program. A literature search identified reports of plerixafor-based mobilization during compassionate access programs. Overall, successful collection of at least 2 × 10(6) CD34+ cells/kg was achieved in ~75% of patients, and about two-thirds of patients went on to HSCT. A greater proportion of patients had successful collections when plerixafor was used in the upfront or preemptive settings. Plerixafor was made available by Health Canada's SAP from September 2008 to December 2010. In 96 of 132 (73%) patients, there was successful collection of at least 2 × 10(6) CD34+ cells/kg. Ninety-nine (75%) patients went on to receive an autologous transplant. Plerixafor-based mobilization is effective in perceived poor mobilizers. The optimal way to incorporate plerixafor into a mobilization strategy, however, remains to be determined. Centre-specific analysis of resource utilization may help to identify the most cost-effective way to implement various plerixafor-based mobilization strategies.


Assuntos
Mobilização de Células-Tronco Hematopoéticas/métodos , Compostos Heterocíclicos/uso terapêutico , Adulto , Idoso , Antígenos CD34/metabolismo , Protocolos de Quimioterapia Combinada Antineoplásica , Autoenxertos , Benzilaminas , Canadá , Ensaios de Uso Compassivo , Análise Custo-Benefício , Ciclamos , Feminino , Neoplasias Hematológicas/tratamento farmacológico , Neoplasias Hematológicas/terapia , Mobilização de Células-Tronco Hematopoéticas/economia , Transplante de Células-Tronco Hematopoéticas/métodos , Células-Tronco Hematopoéticas/efeitos dos fármacos , Células-Tronco Hematopoéticas/imunologia , Compostos Heterocíclicos/economia , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
8.
Bone Marrow Transplant ; 48(7): 953-7, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23334277

RESUMO

The impact of donor-recipient ABO incompatibility on long-term BMT outcomes remains controversial. A common strategy is to deplete the donor marrow of red cells, although this variably reduces the number of CD34+ cells. This 10-year retrospective study assessed the impact of recipient plasma exchange in major ABO-incompatible allogeneic BMT on outcomes and survival. Target Ab titres were ≤ 1:4 for anti-A and ≤ 1:8 for anti-B. Patients with higher titres underwent plasma exchange before marrow infusion. Of 133 patients who underwent allogeneic BMT, 34 had a major ABO-incompatible donor. The median number of exchanges was 2 (range 1-4). There were no acute haemolytic transfusion reactions. Engraftment times, transfusion requirements and acute and chronic GVHD were no different from those of patients with an ABO-identical donor. Treatment-related mortality at 100 days was 21% in the group with a major ABO-incompatible donor and 17% in the group with an identical donor (P=0.8). Plasma exchange of the recipient is a safe method of managing donor-recipient major ABO incompatibility before BMT without the risk of haematopoietic progenitor cell loss associated with red cell depletion of the graft.


Assuntos
Incompatibilidade de Grupos Sanguíneos , Transplante de Medula Óssea , Bases de Dados Factuais , Hemaglutininas , Troca Plasmática , Doadores não Relacionados , Adolescente , Adulto , Idoso , Aloenxertos , Criança , Intervalo Livre de Doença , Feminino , Neoplasias Hematológicas/mortalidade , Neoplasias Hematológicas/terapia , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Taxa de Sobrevida , Fatores de Tempo
9.
Diabetologia ; 55(12): 3238-44, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23001376

RESUMO

AIMS/HYPOTHESIS: The Leicester Practice Risk Score (LPRS) is a tool for identifying those at high risk of either impaired glucose regulation (IGR), defined as impaired glucose tolerance and/or impaired fasting glucose, or type 2 diabetes from routine primary care data. The aim of this study was to determine the yield from the LPRS when applied in two diabetes prevention trials. METHODS: Let's Prevent Diabetes (LPD) and Walking Away from Diabetes (WAD) studies used the LPRS to identify people at risk of IGR or type 2 diabetes from 54 general practices. The top 10% at risk within each practice were invited for screening using a 75 g OGTT. The response rate to the invitation and the prevalence of IGR and/or type 2 diabetes in each study were calculated. RESULTS: Of those invited 19.2% (n = 3,449) in LPD and 22.1% (n = 833) in WAD attended. Of those screened for LPD 25.5% (95% CI 24.1, 27.0) had IGR and 4.5% (95% CI 3.8, 5.2) had type 2 diabetes, giving a prevalence of any abnormal glucose tolerance of 30.1% (95% CI 28.5, 31.6). Comparable rates were seen for the WAD study: IGR 26.5% (95% CI 23.5, 29.5), type 2 diabetes 3.0% (95% CI 1.8, 4.2) and IGR/type 2 diabetes 29.5% (95% CI 26.4, 32.6). CONCLUSIONS/INTERPRETATION: Using the LPRS identifies a high yield of people with abnormal glucose tolerance, significantly higher than those seen in a population screening programme in the same locality. The LPRS is an inexpensive and simple way of targeting screening programmes at those with the highest risk.


Assuntos
Intolerância à Glucose , Programas de Rastreamento/métodos , Estado Pré-Diabético/prevenção & controle , Adulto , Idoso , Glicemia/metabolismo , Feminino , Teste de Tolerância a Glucose , Hemoglobinas Glicadas/metabolismo , Prioridades em Saúde , Promoção da Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Estado Pré-Diabético/sangue , Estado Pré-Diabético/epidemiologia , Prevalência , Medição de Risco , Fatores de Risco , Reino Unido/epidemiologia
10.
Antimicrob Agents Chemother ; 55(12): 5732-9, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21930891

RESUMO

Posaconazole prophylaxis has proven highly effective in preventing invasive fungal infections, despite relatively low serum concentrations. However, high tissue levels of this agent have been reported in treated patients. We therefore hypothesized that the intracellular levels of antifungal agents are an important factor in determining the success of fungal prophylaxis. To examine the effect of host cell-associated antifungals on the growth of medically important molds, we exposed cells to antifungal agents and removed the extracellular drug prior to infection. Epithelial cells loaded with posaconazole and its parent molecule itraconazole, but not other antifungals, were able to inhibit fungal growth for at least 48 h and were protected from damage caused by infection. Cell-associated posaconazole levels were 40- to 50-fold higher than extracellular levels, and the drug was predominantly detected in cellular membranes. Fungistatic levels of posaconazole persisted within epithelial cells for up to 48 h. Therefore, the concentration of posaconazole in mammalian host cell membranes mediates its efficacy in prophylactic regimens and likely explains the observed discrepancy between serum antifungal levels and efficacy.


Assuntos
Antifúngicos/farmacocinética , Aspergillus fumigatus/efeitos dos fármacos , Membrana Celular/metabolismo , Células Epiteliais/metabolismo , Macrófagos/metabolismo , Micoses/prevenção & controle , Triazóis/farmacocinética , Antifúngicos/farmacologia , Aspergillus fumigatus/crescimento & desenvolvimento , Linhagem Celular , Quimioprevenção , Células Epiteliais/microbiologia , Humanos , Itraconazol/farmacocinética , Itraconazol/farmacologia , Pulmão/citologia , Macrófagos/microbiologia , Triazóis/farmacologia
11.
J Cyst Fibros ; 10 Suppl 2: S53-66, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21658643

RESUMO

In the majority of cases, there is no difficulty in diagnosing Cystic Fibrosis (CF). However, there may be wide variation in signs and symptoms between individuals which encourage the scientific community to constantly improve the diagnostic tests available and develop better methods to come to a final diagnosis in patients with milder phenotypes. This paper is the result of discussions held at meetings of the European Cystic Fibrosis Society Diagnostic Network supported by EuroCareCF. CFTR bioassays in the nasal epithelium (nasal potential difference measurements) and the rectal mucosa (intestinal current measurements) are discussed in detail including efforts to standardize the techniques across Europe. New approaches to evaluate the sweat gland, future of genetic testing and methods on the horizon like CFTR expression in human leucocytes and erythrocytes are discussed briefly.


Assuntos
Fibrose Cística/diagnóstico , Técnicas de Diagnóstico do Sistema Respiratório/tendências , Medicina/tendências , Europa (Continente) , Humanos
12.
J Cyst Fibros ; 10 Suppl 2: S86-102, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21658649

RESUMO

Several diseases have been clinically or genetically related to cystic fibrosis (CF), but a consensus definition is lacking. Here, we present a proposal for consensus guidelines on cystic fibrosis transmembrane conductance regulator (CFTR)-related disorders (CFTR-RDs), reached after expert discussion and two dedicated workshops. A CFTR-RD may be defined as "a clinical entity associated with CFTR dysfunction that does not fulfil diagnostic criteria for CF". The utility of sweat testing, mutation analysis, nasal potential difference, and/or intestinal current measurement for the differential diagnosis of CF and CFTR-RD is discussed. Algorithms which use genetic and functional diagnostic tests to distinguish CF and CFTR-RDs are presented. According to present knowledge, congenital bilateral absence of vas deferens (CBAVD), acute recurrent or chronic pancreatitis and disseminated bronchiectasis, all with CFTR dysfunction, are CFTR-RDs.


Assuntos
Regulador de Condutância Transmembrana em Fibrose Cística/genética , Fibrose Cística/classificação , Fibrose Cística/genética , Medicina/normas , Guias de Prática Clínica como Assunto , Fibrose Cística/fisiopatologia , Europa (Continente) , Humanos
13.
Br J Pharmacol ; 153(6): 1311-23, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18223673

RESUMO

BACKGROUND AND PURPOSE: Cystic fibrosis (CF) is caused by dysfunction of the cystic fibrosis transmembrane conductance regulator (CFTR) Cl(-) channel. In the search for new CF therapies, small molecules have been identified that rescue the defective channel gating of CF mutants (termed CFTR potentiators). Here, we investigate the long-term effects of genistein, the best-studied CFTR potentiator, on the expression and function of CFTR. EXPERIMENTAL APPROACH: We pre-treated baby hamster kidney (BHK) cells expressing wild-type or F508del-CFTR (the most common CF mutant) with concentrations of genistein that potentiate (30 microM) or inhibit (100 microM) CFTR function for 2 or 24 h at 37 degrees C before examining CFTR maturation, expression and single-channel activity. KEY RESULTS: Using the iodide efflux technique, we found that genistein pre-treatment failed to restore function to F508del-CFTR, but altered that of wild-type CFTR. Pre-treatment of cells with genistein for 2 h had little effect on CFTR processing, whereas pre-treatment for 24 h either augmented (30 microM genistein) or impaired (100 microM genistein) CFTR maturation. Using immunocytochemistry, we found that all genistein pre-treatments increased the localization of CFTR protein to the cell surface. However, following the incubation of cells with genistein (100 microM) for 2 h, individual CFTR Cl(-) channels exhibited characteristics of channel block upon channel activation. CONCLUSIONS AND IMPLICATIONS: Genistein pre-treatment alters the maturation, cell surface expression and single-channel function of CFTR in ways distinct from its acute effects. Thus, CFTR potentiators have the potential to influence CFTR by mechanisms distinct from their effects on channel gating.


Assuntos
Regulador de Condutância Transmembrana em Fibrose Cística/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Genisteína/farmacologia , Animais , Linhagem Celular , Cricetinae , Regulador de Condutância Transmembrana em Fibrose Cística/metabolismo , Relação Dose-Resposta a Droga , Genisteína/administração & dosagem , Humanos , Imuno-Histoquímica , Iodetos/metabolismo , Ativação do Canal Iônico/efeitos dos fármacos , Rim , Transporte Proteico/efeitos dos fármacos , Fatores de Tempo
14.
Infect Immun ; 73(11): 7366-74, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16239535

RESUMO

Candida albicans is the most common fungal pathogen of humans. The recent discovery of sexuality in this organism has led to the demonstration of a mating type locus which is usually heterozygous, although some isolates are homozygous. Tetraploids can be formed between homozygotes of the opposite mating type. However, the role of the mating process and tetraploid formation in virulence has not been investigated. We describe here experiments using a murine model of disseminated candidiasis which demonstrate that in three strains, including CAI-4, the most commonly used strain background, tetraploids are less virulent than diploids and can undergo changes in ploidy during infection. In contrast to reports with other strains, we find that MTL homozygotes are almost as virulent as the heterozygotes. These results show that the level of ploidy in Candida albicans can affect virulence, but the mating type configuration does not necessarily do so.


Assuntos
Candida albicans/genética , Candida albicans/patogenicidade , Genes Fúngicos Tipo Acasalamento/genética , Genes Fúngicos Tipo Acasalamento/fisiologia , Ploidias , Animais , Candida albicans/fisiologia , Proteínas Fúngicas/genética , Proteínas Fúngicas/fisiologia , Genótipo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Poliploidia , Virulência/genética
15.
J Cell Mol Med ; 9(2): 421-37, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15963261

RESUMO

To identify overlapping and non-overlapping functions for TSP-1 and alphavbeta6, we crossed TSP-1-null and beta6-null mice and compared the phenotype of the double-null mice with those of wild-type and single-null mice. The double-null mice exhibited focal acute and organizing pneumonia that was more severe than the wild-type and single-null mice as well as a significantly higher incidence of inflammation in tissues other than the lung. The TSP-1-null and beta6-null mice exhibited a five to eight-fold increase in granulocyte recruitment to the lung three days after exposure to lipopolysaccharide. They also had abnormalities that were infrequently observed in the wild-type and single-null mice, including heart degeneration (8.35% in wild-type and 28.1% in double-null mice), hyperplasia of the glandular of the stomach (2.8% in wild-type and 21.1% in double-null mice) and endometrial hyperplasia (0% in wild-type and 38.5% in double-null females). Furthermore, the beta6-null and double-null mice displayed a significant elevation in benign and malignant cancers. Stomach papillomas, squamous cell carcinomas of the ear and stomach, and adenocarcinomas of the lungs, vagina/cervix and colon were observed with the highest frequency. These data demonstrate that TSP-1 and alphavbeta6 are involved in regulation of the immune system and epithelial homeostasis. They also indicate that alphavbeta6 functions as a tumor suppressor gene and that activation of TGFbeta by TSP-1 and alphavbeta6 contributes to normal tissue architecture and function.


Assuntos
Inflamação/genética , Cadeias beta de Integrinas/genética , Neoplasias/genética , Trombospondina 1/genética , Alopecia/genética , Animais , Cardiomiopatias/genética , Cardiomiopatias/patologia , Cruzamentos Genéticos , Epitélio/patologia , Feminino , Doenças dos Genitais Femininos/genética , Doenças dos Genitais Femininos/patologia , Hiperplasia/genética , Hiperplasia/patologia , Inflamação/patologia , Longevidade/genética , Pneumopatias/genética , Pneumopatias/patologia , Masculino , Camundongos , Camundongos Knockout , Camundongos Mutantes , Neoplasias/patologia , Neoplasias de Células Escamosas/genética , Neoplasias de Células Escamosas/patologia , Fenótipo , Pneumonia/genética , Pneumonia/patologia , Gastropatias/genética , Gastropatias/patologia , Fator de Crescimento Transformador beta/metabolismo
16.
Mol Membr Biol ; 21(1): 27-38, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-14668136

RESUMO

Niflumic acid is widely used to inhibit Ca(2+) -activated Cl(-) channels. However, the chemical structure of niflumic acid resembles that of diphenylamine-2-carboxylate, a drug that inhibits the cystic fibrosis transmembrane conductance regulator (CFTR) Cl(-) channel. To investigate how niflumic acid inhibits CFTR Cl(-) channel, we studied recombinant wild-type human CFTR in excised inside-out membrane patches. When added to the intracellular solution, niflumic acid caused a concentration- and voltage-dependent decrease of CFTR Cl(-) current with half-maximal inhibitory concentration (K(i)) of 253 microM and Hill co-efficient of approximately 1, at -50 mV. Niflumic acid inhibition of single CFTR Cl(-) channels was characterized by a very fast, flickery block that decreased dramatically current amplitude without altering open-probability. Consistent with these data, spectral analysis of CFTR Cl(-) currents suggested that channel block by niflumic acid was described by the closed <--> open <--> blocked kinetic scheme with blocker on rate (k(on)) = 13.9 x 10(6) M(-1)s(-1), off rate (k(off))=3348 s(-1) and dissociation constant (K(d)) = 241 microM, at -50 mV. Based on these data, we tested the effects of niflumic acid on transepithelial Cl(-) secretion and cyst growth using type I MDCK epithelial cells. Niflumic acid (200 microM) inhibited cAMP-stimulated, bumetanide-sensitive short-circuit current by 55%. Moreover, the drug potently retarded cyst growth. We conclude that niflumic acid is an open-channel blocker of CFTR that inhibits Cl(-) permeation by plugging the channel pore. It or related agents might be of value in the development of new therapies for autosomal dominant polycystic kidney disease.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Regulador de Condutância Transmembrana em Fibrose Cística/antagonistas & inibidores , Ativação do Canal Iônico/efeitos dos fármacos , Ácido Niflúmico/farmacologia , Proteínas Recombinantes/antagonistas & inibidores , Animais , Linhagem Celular , Cloretos/metabolismo , Regulador de Condutância Transmembrana em Fibrose Cística/química , Regulador de Condutância Transmembrana em Fibrose Cística/genética , Cães , Eletrofisiologia , Humanos , Ativação do Canal Iônico/genética , Potenciais da Membrana/efeitos dos fármacos , Estrutura Molecular , Técnicas de Patch-Clamp , Proteínas Recombinantes/química , Proteínas Recombinantes/genética
18.
J Exp Clin Cancer Res ; 21(3 Suppl): 107-14, 2002 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12585664

RESUMO

The UK national study of magnetic resonance imaging as a method of screening for breast cancer (MARIBS) is in progress. The study design, accrual to date, and related research projects are described. Revised accrual rates and expected recruitment are given. 15 cancers have been detected to date, from a total of 1236 screening measurements. This event rate and the tumour grades reported are compared with recent reports from other studies in women at high risk of breast cancer.


Assuntos
Neoplasias da Mama/diagnóstico , Imageamento por Ressonância Magnética , Programas de Rastreamento , Adulto , Neoplasias da Mama/genética , Estudos de Coortes , Feminino , Genes BRCA1 , Genes BRCA2 , Predisposição Genética para Doença , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética/métodos , Mamografia , Pessoa de Meia-Idade , Mutação , Seleção de Pacientes , Controle de Qualidade , Sensibilidade e Especificidade
19.
Chest ; 120(1 Suppl): 49S-53S, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11451914

RESUMO

The integrin alphavbeta6 is restricted to epithelial cells and is dramatically induced in response to injury and inflammation. Mice expressing a null mutation of this integrin develop exaggerated inflammation of the lungs and skin, but are dramatically protected from bleomycin-induced pulmonary fibrosis. This phenotype led to the identification of a unique role for this integrin in binding to and activating latent extracellular complexes of the anti-inflammatory, profibrotic cytokine, transforming growth factor-beta(1). This integrin-mediated activation is tightly spatially restricted and appears to require direct presentation of the activated cytokine to receptors on adjacent cells. The process also requires distinct regions of the beta6-subunit cytoplasmic domain and an intact actin cytoskeleton, suggesting the existence of additional cellular mechanisms to regulate this process. If this mechanism is found to be as important in humans as it is in mice, the integrin and as yet to be identified pathways for cellular regulation of this process could be exciting new targets for intervention in fibrotic diseases of the lung and other epithelial organs.


Assuntos
Antígenos de Neoplasias , Integrinas/fisiologia , Fibrose Pulmonar/fisiopatologia , Fator de Crescimento Transformador beta/fisiologia , Animais , Integrinas/genética , Camundongos , Camundongos Knockout , Modelos Animais , Mutação , Transdução de Sinais/fisiologia , Fator de Crescimento Transformador beta1
20.
J Invest Dermatol ; 117(1): 67-73, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11442751

RESUMO

The integrin alphavbeta6 is a fibronectin receptor whose expression is not detectable on normal oral epithelium but is increased significantly in healing and in oral epithelial dysplasia and oral squamous cell carcinoma, suggesting it may promote changes associated with tumor development. To study whether alphavbeta6 may drive invasive behavior we have used transfection and retroviral infection to create a panel of epithelial cell lines expressing various levels of alphavbeta6. We report that increased expression of alphavbeta6 in malignant keratinocytes promotes invasion and leads to an increased capacity for migration towards fibronectin. alphavbeta6 expression may have a significant role in contributing to the malignant behavior of epithelial cells.


Assuntos
Antígenos de Neoplasias , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/fisiopatologia , Movimento Celular/fisiologia , Integrinas/genética , Neoplasias Cutâneas/patologia , Neoplasias Cutâneas/fisiopatologia , Materiais Biocompatíveis , Adesão Celular/fisiologia , Divisão Celular/fisiologia , Movimento Celular/efeitos dos fármacos , Colágeno , Combinação de Medicamentos , Fibronectinas/metabolismo , Fibronectinas/farmacologia , Adesões Focais/química , Regulação Neoplásica da Expressão Gênica , Humanos , Integrinas/análise , Integrinas/metabolismo , Queratinócitos/metabolismo , Queratinócitos/patologia , Laminina , Neoplasias Bucais/patologia , Neoplasias Bucais/fisiopatologia , Invasividade Neoplásica/patologia , Invasividade Neoplásica/fisiopatologia , Plásticos , Proteoglicanas , Receptores de Fibronectina/análise , Receptores de Fibronectina/metabolismo , Retroviridae/genética , Transfecção , Células Tumorais Cultivadas
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