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1.
Adv Exp Med Biol ; 1185: 425-430, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31884649

RESUMO

Previous studies of retinal pigment epithelium (RPE) morphology found cell-level and spatial patterning differences in many quantitative metrics in comparing normal and disease conditions. However, most of these studies examined eyes from deceased animals. Here we sought to compare noninvasively imaged RPE cells from live mice to histopathology. We describe changes to improve noninvasive imaging of RPE in the live mouse. In retinal diseases, there can be invasion by Iba1-positive cells, which can be detected by noninvasive imaging techniques. Here we can detect potential Iba1-positive cells at the level of the RPE noninvasively.


Assuntos
Epitélio Pigmentado da Retina/diagnóstico por imagem , Cicatrização , Animais , Camundongos , Epitélio Pigmentado da Retina/patologia
2.
Br J Sports Med ; 50(18): 1135-41, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26701925

RESUMO

BACKGROUND: Skeletal maturity and age-related changes in the composition of the glenoid labrum and joint capsule may influence rates of recurrent instability in children. We systematically review risk factors which predispose children to recurrent shoulder instability. METHODS: The systematic review-concerned studies published before May 2015. Statistical analysis was undertaken to compare rates of recurrence for each extracted risk factor. Pooled ORs were analysed using random effects meta-analysis. RESULTS: 6 retrospective cohort studies met the inclusion criteria. 8 risk factors were identified across the studies including age, sex, shoulder dominance and injury side, mechanism of injury, state of physis closure, and Hill-Sachs and Bankart lesions. The rate of recurrent instability was 73%. Children aged 14-18 years were 24 times more likely to experience recurrent instability than children aged 13 years and less (93% vs 40%; OR=24.14, 95% CI (3.71 to 156.99), Z=3.33, p=0.001, I(2)=6.83%). There was a non-significant trend indicating males were 3.4 times more likely to experience recurrent instability (OR=3.44, 95% CI (0.98 to 12.06), Z=1.93, p=0.053, I(2)=0%). Analysis of one study found that children with a closed physis are 14 times more likely to experience recurrent instability compared with those with an open physis (OR=14.0, 95% CI (1.46 to 134.25), Z=2.29, p=0.02, I(2)=0%) . CONCLUSIONS: Male children aged 14 years and over had the greatest risk of recurrent shoulder instability following a first-time traumatic anterior shoulder dislocation. This meta-analysis summarises a mix of 6 acceptable and poor quality level III retrospective cohort studies. Further examination of this population with blinded prospective cohort studies will assist clinicians in the appropriate management of first-time traumatic anterior shoulder dislocation.


Assuntos
Instabilidade Articular/etiologia , Articulação do Ombro/patologia , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Recidiva , Fatores de Risco , Luxação do Ombro/etiologia , Lesões do Ombro/fisiopatologia
3.
Br J Sports Med ; 49(14): 913-22, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25900943

RESUMO

BACKGROUND: Recurrent instability following a first-time anterior traumatic shoulder dislocation may exceed 26%. We systematically reviewed risk factors which predispose this population to events of recurrence. METHODS: A systematic review of studies published before 1 July 2014. Risk factors which predispose recurrence following a first-time traumatic anterior shoulder dislocation were documented and rates of recurrence were compared. Pooled ORs were analysed using random-effects meta-analysis. RESULTS: Ten studies comprising 1324 participants met the criteria for inclusion. Recurrent instability following a first-time traumatic anterior shoulder dislocation was 39%. Increased risk of recurrent instability was reported in people aged 40 years and under (OR=13.46), in men (OR=3.18) and in people with hyperlaxity (OR=2.68). Decreased risk of recurrent instability was reported in people with a greater tuberosity fracture (OR=0.13). The rate of recurrent instability decreased as time from the initial dislocation increased. Other factors such as a bony Bankart lesion, nerve palsy and occupation influenced rates of recurrent instability. CONCLUSIONS: Sex, age at initial dislocation, time from initial dislocation, hyperlaxity and greater tuberosity fractures were key risk factors in at least two good quality cohort studies resulting in strong evidence as concluded in the GRADE criteria. Although bony Bankart lesions, Hill Sachs lesions, occupation, physiotherapy treatment and nerve palsy were risk factors for recurrent instability, the evidence was weak using the GRADE criteria-these findings relied on poorer quality studies or were inconsistent among studies.


Assuntos
Instabilidade Articular/etiologia , Luxação do Ombro/etiologia , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Suscetibilidade a Doenças , Feminino , Humanos , Instabilidade Articular/patologia , Masculino , Pessoa de Meia-Idade , Recidiva , Fatores de Risco , Fatores Sexuais , Luxação do Ombro/patologia , Adulto Jovem
4.
Environ Res ; 127: 63-73, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24267795

RESUMO

The six week eruption of Eyjafjallajökull volcano in 2010 produced heavy ash fall in a sparsely populated area of southern and south eastern Iceland and disrupted European commercial flights for at least 6 days. We adopted a protocol for the rapid analysis of volcanic ash particles, for the purpose of informing respiratory health risk assessments. Ash collected from deposits underwent a multi-laboratory physicochemical and toxicological investigation of their mineralogical parameters associated with bio-reactivity, and selected in vitro toxicology assays related to pulmonary inflammatory responses. Ash from the eruption of Grímsvötn, Iceland, in 2011 was also studied. The results were benchmarked against ash from Soufrière Hills volcano, Montserrat, which has been extensively studied since the onset of eruptive activity in 1995. For Eyjafjallajökull, the grain size distributions were variable: 2-13 vol% of the bulk samples were <4 µm, with the most explosive phases of the eruption generating abundant respirable particulate matter. In contrast, the Grímsvötn ash was almost uniformly coarse (<3.5 vol%<4 µm material). Surface area ranged from 0.3 to 7.7 m2 g(-1) for Eyjafjallajökull but was very low for Grímsvötn (<0.6 m2 g(-1)). There were few fibre-like particles (which were unrelated to asbestos) and the crystalline silica content was negligible in both eruptions, whereas Soufrière Hills ash was cristobalite-rich with a known potential to cause silicosis. All samples displayed a low ability to deplete lung antioxidant defences, showed little haemolysis and low acute cytotoxicity in human alveolar type-1 like epithelial cells (TT1). However, cell-free tests showed substantial hydroxyl radical generation in the presence of hydrogen peroxide for Grímsvötn samples, as expected for basaltic, Fe-rich ash. Cellular mediators MCP-1, IL-6, and IL-8 showed chronic pro-inflammatory responses in Eyjafjallajökull, Grímsvötn and Soufrière Hills samples, despite substantial differences in the sample mineralogy and eruptive styles. The value of the pro-inflammatory profiles in differentiating the potential respiratory health hazard of volcanic ashes remains uncertain in a protocol designed to inform public health risk assessment, and further research on their role in volcanic crises is warranted.


Assuntos
Poluentes Atmosféricos/toxicidade , Pulmão/efeitos dos fármacos , Erupções Vulcânicas/análise , Linhagem Celular/efeitos dos fármacos , Células Epiteliais/efeitos dos fármacos , Humanos , Radical Hidroxila/metabolismo , Islândia , Inflamação/induzido quimicamente , Inflamação/metabolismo , Mediadores da Inflamação/metabolismo , Pulmão/fisiopatologia , Minerais/análise , Tamanho da Partícula , Medição de Risco , Dióxido de Silício , Testes de Toxicidade
5.
Eur Respir J ; 39(3): 546-57, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21828028

RESUMO

Lung exposure to metal oxide nanoparticles (NPs) comprising soluble metal haptens may produce T-helper cell type 1 (Th1)- and Th17-associated delayed-type hypersensitivity (DTH) responses and pulmonary alveolar proteinosis (PAP). In order to study this, haptenic metal oxide NPs (NiO, Co(3)O(4), Cr(2)O(3) and CuO) were instilled into the lungs of female Wistar rats, and the immunoinflammatory responses were assessed at 24 h and 4 weeks post-instillation. Primary culture of alveolar macrophages from Wistar rats was used to evaluate the effect of the NPs on the ability to clear surfactant. NiO NPs induced chronic interstitial inflammation and pro-inflammatory Th1 and Th17 immune responses characterised by increases in the cytokines monocyte chemotactic protein (MCP)-1/CCL2, interleukin (IL)-12 p40, interferon-γ and IL-17A, whilst similar pathological responses induced by Co(3)O(4) NPs were associated with increases in MCP-1/CCL2 and IL-12 p40. However, neither Cr(2)O(3) nor CuO NPs elicited immunoinflammatory reactions. PAP was induced by both NiO and Co(3)O(4) NPs during the chronic phase. PAP was associated with over-production of surfactant by proliferation of type II cells and impaired clearance of surfactant by macrophages. These findings have implications for the risk management of occupational NP exposure and provide evidence that haptenic metal oxide NPs can induce chronic progressive lung immune responses via a DTH-like mechanism.


Assuntos
Cobalto/toxicidade , Nanopartículas Metálicas/efeitos adversos , Níquel/toxicidade , Óxidos/toxicidade , Proteinose Alveolar Pulmonar/induzido quimicamente , Animais , Líquido da Lavagem Broncoalveolar/citologia , Proliferação de Células , Células Cultivadas/imunologia , Compostos de Cromo/toxicidade , Cobre/toxicidade , Citocinas/biossíntese , Citocinas/imunologia , Feminino , Reação a Corpo Estranho/induzido quimicamente , Reação a Corpo Estranho/imunologia , Hipersensibilidade Tardia/induzido quimicamente , Hipersensibilidade Tardia/imunologia , Pulmão/efeitos dos fármacos , Pulmão/metabolismo , Pulmão/patologia , Macrófagos Alveolares/efeitos dos fármacos , Macrófagos Alveolares/imunologia , Macrófagos Alveolares/metabolismo , Nanopartículas Metálicas/ultraestrutura , Proteinose Alveolar Pulmonar/imunologia , Surfactantes Pulmonares/metabolismo , Ratos , Ratos Wistar
6.
Nat Med ; 2(1): 72-9, 1996 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8564846

RESUMO

The anticancer agent paclitaxel (Taxol) stabilizes tubulin polymerization resulting in arrest in mitosis and apoptotic cell death. Normal human fibroblasts depleted of functional p53 by SV40 T antigen or HPV-16 E6, and primary embryo fibroblasts from p53 null mice showed seven- to ninefold increased cytotoxicity by paclitaxel. Reduced levels of p53 correlated with increased G2/M phase arrest, micronucleation, and p53-independent paclitaxel-induced apoptosis. Surviving cells with intact p53 progressed through mitosis and transiently accumulated in the subsequent G1 phase, coincident with increased p53 and p21cip1,waf1 protein levels. These results are in contrast to studies linking p53 loss with resistance to DNA damaging anticancer agents.


Assuntos
Antineoplásicos Fitogênicos/toxicidade , Apoptose/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Paclitaxel/toxicidade , Proteína Supressora de Tumor p53/fisiologia , Animais , Antígenos Transformantes de Poliomavirus/biossíntese , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Relação Dose-Resposta a Droga , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Fibroblastos/patologia , Fase G2/efeitos dos fármacos , Células HeLa , Humanos , Camundongos , Camundongos Knockout , Camundongos Transgênicos , Mitose/efeitos dos fármacos , Proteínas Oncogênicas Virais/biossíntese , Proteínas Repressoras/biossíntese , Proteína Supressora de Tumor p53/deficiência , Proteína Supressora de Tumor p53/genética
7.
Inhal Toxicol ; 23(7): 372-91, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21639707

RESUMO

The marked difference in biopersistence and pathological response between chrysotile and amphibole asbestos has been well documented. This study is unique in that it has examined a commercial chrysotile product that was used as a joint compound. The pathological response was quantified in the lung and translocation of fibers to and pathological response in the pleural cavity determined. This paper presents the final results from the study. Rats were exposed by inhalation 6 h/day for 5 days to a well-defined fiber aerosol. Subgroups were examined through 1 year. The translocation to and pathological response in the pleura was examined by scanning electron microscopy and confocal microscopy (CM) using noninvasive methods. The number and size of fibers was quantified using transmission electron microscopy and CM. This is the first study to use such techniques to characterize fiber translocation to and the response of the pleural cavity. Amosite fibers were found to remain partly or fully imbedded in the interstitial space through 1 year and quickly produced granulomas (0 days) and interstitial fibrosis (28 days). Amosite fibers were observed penetrating the visceral pleural wall and were found on the parietal pleural within 7 days postexposure with a concomitant inflammatory response seen by 14 days. Pleural fibrin deposition, fibrosis, and adhesions were observed, similar to that reported in humans in response to amphibole asbestos. No cellular or inflammatory response was observed in the lung or the pleural cavity in response to the chrysotile and sanded particles (CSP) exposure. These results provide confirmation of the important differences between CSP and amphibole asbestos.


Assuntos
Amianto Amosita/toxicidade , Asbestos Serpentinas/toxicidade , Exposição por Inalação/efeitos adversos , Pulmão/patologia , Pleura/patologia , Aerossóis , Animais , Amianto Amosita/farmacocinética , Asbestos Serpentinas/farmacocinética , Determinação de Ponto Final , Fibrose , Masculino , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Tamanho da Partícula , Material Particulado/farmacocinética , Material Particulado/toxicidade , Projetos Piloto , Pleura/ultraestrutura , Cavidade Pleural/patologia , Ratos , Ratos Wistar , Fatores de Tempo , Estudos de Validação como Assunto
8.
Am J Physiol Lung Cell Mol Physiol ; 299(2): L263-71, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20435687

RESUMO

Induction of effective inflammation in the lung in response to environmental and microbial stimuli is dependent on cooperative signaling between leukocytes and lung tissue cells. We explored how these inflammatory networks are modulated by diesel exhaust particles (DEP) using cocultures of human monocytes with epithelial cells. Cocultures, or monoculture controls, were treated with DEP in the presence or absence of LPS or flagellin. Production of cytokines was explored by Western blotting and ELISA; cell signaling was analyzed by Western blotting. Here, we show that responses of epithelial cells to DEP are amplified by the presence of monocytes. DEP amplified the responses of cellular cocultures to very low doses of TLR agonists. In addition, in the presence of DEP, the responses induced by LPS or flagellin were less amenable to antagonism by the physiological IL-1 antagonist, IL-1ra. This was paralleled by the uncoupling of IL-1 production and release from monocytes, potentially attributable to an ability of DEP to sequester or degrade extracellular ATP. These data describe a model of inflammation where DEP amplifies responses to low concentrations of microbial agonists and alters the nature of the inflammatory milieu induced by TLR agonists.


Assuntos
Inflamação/imunologia , Pulmão/imunologia , Emissões de Veículos/toxicidade , Trifosfato de Adenosina/metabolismo , Linhagem Celular , Técnicas de Cocultura , Citocinas/biossíntese , Flagelina/farmacologia , Humanos , Proteína Antagonista do Receptor de Interleucina 1/imunologia , Interleucina-1/fisiologia , Interleucina-1beta/biossíntese , Interleucina-8/biossíntese , Lipopolissacarídeos/farmacologia , Monócitos/imunologia , Mucosa Respiratória/citologia , Transdução de Sinais/fisiologia , Receptores Toll-Like/agonistas
9.
Inhal Toxicol ; 22(11): 937-62, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20695727

RESUMO

The pathological response and translocation of a commercial chrysotile product similar to that which was used through the mid-1970s in a joint compound intended for sealing the interface between adjacent wall boards was evaluated in comparison to amosite asbestos. This study was unique in that it presents a combined real-world exposure and was the first study to investigate whether there were differences between chrysotile and amosite asbestos fibers in time course, size distribution, and pathological response in the pleural cavity. Rats were exposed by inhalation 6 h/day for 5 days to either sanded joint compound consisting of both chrysotile fibers and sanded joint compound particles (CSP) or amosite asbestos. Subgroups were examined through 1-year postexposure. No pathological response was observed at any time point in the CSP-exposure group. The long chrysotile fibers (L > 20 microm) cleared rapidly (T(1/2) of 4.5 days) and were not observed in the pleural cavity. In contrast, a rapid inflammatory response occurred in the lung following exposure to amosite resulting in Wagner grade 4 interstitial fibrosis within 28 days. Long amosite fibers had a T(1/2) > 1000 days and were observed in the pleural cavity within 7 days postexposure. By 90 days the long amosite fibers were associated with a marked inflammatory response on the parietal pleural. This study provides support that CSP following inhalation would not initiate an inflammatory response in the lung, and that the chrysotile fibers present do not migrate to, or cause an inflammatory response in the pleural cavity, the site of mesothelioma formation.


Assuntos
Amianto Amosita/administração & dosagem , Asbestos Serpentinas/administração & dosagem , Exposição por Inalação/efeitos adversos , Pulmão/patologia , Material Particulado/administração & dosagem , Pleura/patologia , Animais , Amianto Amosita/metabolismo , Amianto Amosita/toxicidade , Asbestos Serpentinas/metabolismo , Asbestos Serpentinas/toxicidade , Pulmão/efeitos dos fármacos , Pulmão/metabolismo , Masculino , Material Particulado/toxicidade , Projetos Piloto , Pleura/efeitos dos fármacos , Pleura/metabolismo , Ratos , Fatores de Tempo
10.
J R Coll Physicians Edinb ; 40(1): 33-6, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21125037

RESUMO

The placebo-corrected incidence of rhabdomyolysis in a systematic review of 20 statin trials was 1.6/100,000 per year. It is likely to be higher than this in everyday clinical practice when statins are knowingly or inadvertently co-prescribed with drugs that interfere with their metabolism. We report a case of rhabdomyolysis causing muscle weakness and prolonging an episode of dialysis-dependent acute kidney injury, which occurred when fusidic acid was co-prescribed with atorvastatin. Renal function and muscle power recovered when both drugs were withdrawn. We found four other cases of rhabdomyolysis with fusidic acid and atorvastatin and three with fusidic acid and simvastatin in the literature, a review of which suggests that the risks of rhabdomyolysis vary with the extent to which an individual statin is dependent for its metabolism on the cytochrome P450 3A4 isoenzyme and the degree to which this isoenzyme's activity is inhibited by a particular antimicrobial. Of note, the interaction between statins and fusidic acid did not feature in seven of eight recent reviews of statin toxicity. Our case report highlights the importance of close monitoring of patients on statins, especially when new drugs are started or if patients become unwell, by checking creatine kinase and liver function tests and by examining for new muscle weakness. Our review of statin-antimicrobial drug interactions suggests that fusidic acid is another CYP450 3A4 enzyme inhibitor with the potential to cause rhabdomyolysis when co-prescribed with simvastatin and atorvastatin.


Assuntos
Anticolesterolemiantes/farmacologia , Ácido Fusídico/farmacologia , Ácidos Heptanoicos/farmacologia , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Pirróis/farmacologia , Rabdomiólise/induzido quimicamente , Idoso , Anticolesterolemiantes/administração & dosagem , Atorvastatina , Interações Medicamentosas , Ácido Fusídico/administração & dosagem , Ácidos Heptanoicos/administração & dosagem , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/administração & dosagem , Masculino , Pirróis/administração & dosagem
11.
Thorax ; 63(4): 306-11, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18024535

RESUMO

RATIONALE: Chronic obstructive pulmonary disease (COPD) is associated with a 2-3-fold increase in the risk of ischaemic heart disease, stroke and sudden death. The mechanisms responsible for this association are not clear and appear to be independent of smoking history. OBJECTIVE: We test the hypothesis that patients with COPD have increased arterial stiffness and blood pressure in comparison with age and smoking matched controls. METHODS: In a prospective case control study, we recruited 102 patients with COPD and 103 healthy controls matched for age and smoking status. Patients were assessed by clinical history and spirometry, with arterial stiffness and blood pressure determined using radial artery applanation tonometry and sphygmomanometry. RESULTS: Patients with COPD had increased arterial stiffness compared with matched controls, with elevated augmentation pressure (17 (1) vs 14 (1) mm Hg; p = 0.005) and a reduced time to wave reflection (131 (1) vs 137 (2) ms; p = 0.004). These differences were associated with increases in both diastolic (82 (1) vs 78 (1) mm Hg; p = 0.005) and systolic blood pressure (147 (2) vs 132 (2) mm Hg; p<0.001). Serum C reactive protein concentrations were threefold higher in patients (6.1 (0.9) vs 2.3 (0.4) mg/l; p = 0.001). Data are presented as mean (SEM). CONCLUSIONS: Patients with COPD have increased arterial stiffness and blood pressure in comparison with controls matched for age and smoking status. We speculate that increased systemic inflammation and vascular dysfunction could potentially explain the excess cardiovascular morbidity and mortality associated with COPD.


Assuntos
Morte Súbita Cardíaca/etiologia , Isquemia Miocárdica/etiologia , Doença Pulmonar Obstrutiva Crônica/complicações , Acidente Vascular Cerebral/etiologia , Estudos de Casos e Controles , Elasticidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Isquemia Miocárdica/fisiopatologia , Estudos Prospectivos , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Pulso Arterial , Artéria Radial/fisiologia , Fatores de Risco , Acidente Vascular Cerebral/fisiopatologia , Resistência Vascular/fisiologia
12.
Eur Respir J ; 31(2): 241-51, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18057054

RESUMO

The epidemiological association between cancer and exposure to ambient air pollution particles (particles with a 50% cut-off aerodynamic diameter of 10 microm (PM(10))) has been related to the ability of PM(10) and its constituent nanoparticles (NPs) to cause reactive oxidative species (ROS)-driven DNA damage. However, there are no data on the molecular response to these genotoxic effects. In order to assess whether PM(10), NP and ROS-driven DNA damage induce carcinogenesis pathways, A549 cells were treated with tert-butyl-hyperperoxide (Tbh), urban dust (UD), carbon black (CB), nanoparticulate CB (NPCB), benzo(a)pyrene (BaP) and NPCB coated with BaP for

Assuntos
Carcinógenos Ambientais/toxicidade , Transformação Celular Neoplásica/induzido quimicamente , Dano ao DNA/efeitos da radiação , Nanopartículas/toxicidade , Análise de Variância , Western Blotting , Linhagem Celular Tumoral , Ensaio Cometa , Quebras de DNA de Cadeia Dupla , Genes BRCA1 , Humanos , Técnicas In Vitro , Análise Multivariada , Mutagênicos/toxicidade , Estresse Oxidativo , Fosforilação , Espécies Reativas de Oxigênio/metabolismo , Sensibilidade e Especificidade
13.
Inhal Toxicol ; 20(1): 53-62, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18236223

RESUMO

We previously demonstrated the importance of the surface area burden as the key dose metric in the elicitation of inflammation in rat lungs by low-solubility, low-toxicity particles (LSLTP). We have now explored the dosimetry of LSLTP in vitro using epithelial cell interleukin (IL)-8 gene expression as a surrogate for potential of particles to cause inflammation. The proximal alveolar region (PAR) of the lung has been identified as a key site for the retention of respirable particles, as it receives high deposition but has slow clearance compared to the larger airways. For these reasons, a few days after exposure to particles the residual dose is concentrated in the PAR region. Re-expressing our rat lung data as particle surface area burden per unit of PAR surface area we obtained a threshold value for onset of inflammation of 1 cm(2)/cm(2). We carried out dose responses in vitro for onset of IL-8 gene expression with the same particles as we had used in vivo. When we expressed the in vitro dose as surface area dose per unit A549cell culture surface area, we obtained a threshold of 1 cm(2)/cm(2). This concordance between proinflammatory effects in vivo (PMN in BAL) and in vitro (epithelial IL-8 gene expression) confirms and supports the utility of the particle surface area metric and the importance of the PAR. These studies also open the way for future in vitro approaches to studying proinflammatory effects of a range of toxic particles based on sound dosimetry that complements animal use in particle toxicology.


Assuntos
Material Particulado/química , Material Particulado/toxicidade , Pneumonia/induzido quimicamente , Alvéolos Pulmonares/efeitos dos fármacos , Animais , Linhagem Celular , Relação Dose-Resposta a Droga , Humanos , Imageamento Tridimensional/métodos , Tamanho da Partícula , Material Particulado/administração & dosagem , Pneumonia/fisiopatologia , Alvéolos Pulmonares/fisiologia , Ratos , Ratos Wistar , Solubilidade , Propriedades de Superfície
14.
Inhal Toxicol ; 20(11): 1009-28, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18788018

RESUMO

In designing a study to evaluate the inhalation biopersistence of a chrysotile asbestos that was used as a component of a joint-compound, a feasibility study was initiated to evaluate the short-term biopersistence of the chrysotile alone and of the chrysotile in combination with the sanded reformulated joint-compound. Two groups of Wistar rats were exposed to either 7RF3 chrysotile (Group 2) or to 7RF3 chrysotile combined with aerosolized sanded joint-compound (Group 3). In addition, a control group was exposed to filtered-air. The chrysotile used in the Ready Mix joint compound is rapidly removed from the lung. The chrysotile alone exposure group had a clearance half-time of fibers L > 20 microm of 2.2 days; in the chrysotile plus sanded exposure group the clearance half-time of fibers L > 20 microm was 2.8 days. However, across all size ranges there was approximately an order of magnitude decrease in the mean number of fibers remaining in the lungs of Group 3 as compared to Group 2 despite similiar aerosol exposures. Histopathological examination showed that the chrysotile exposed lungs had the same appearance as the filtered-air controls. This study uniquely illustrates that additional concurrent exposure to an aerosol of the sanded joint-compound, with large numbers of fine-particles depositing in the lungs, accelerates the recruitment of macrophages, resulting in a tenfold decrease in the number of fibers remaining in the lung. The increased number of macrophages in the chrysotile/sanded joint exposure group was confirmed histologically, with this being the only exposure-related histological finding reported.


Assuntos
Asbestos Serpentinas/farmacocinética , Materiais de Construção , Pulmão/metabolismo , Material Particulado/farmacocinética , Aerossóis , Animais , Asbestos Serpentinas/toxicidade , Câmaras de Exposição Atmosférica , Carga Corporal (Radioterapia) , Materiais de Construção/toxicidade , Estudos de Viabilidade , Exposição por Inalação , Pulmão/efeitos dos fármacos , Pulmão/patologia , Macrófagos/efeitos dos fármacos , Macrófagos/patologia , Masculino , Fibras Minerais , Tamanho da Partícula , Material Particulado/toxicidade , Ratos , Ratos Wistar , Reprodutibilidade dos Testes , Fatores de Tempo
15.
Clin Microbiol Infect ; 24(10): 1066-1069, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29409961

RESUMO

OBJECTIVES: To prospectively evaluate HiberGene's loop-mediated isothermal amplification (LAMP) assay for detection of group B streptococcus (GBS) in maternal recto-vaginal swabs and compare it with enrichment culture. METHODS: Following ethical approval and informed written consent, two low vaginal and rectal swabs were obtained from 400 pregnant women. One swab was tested for GBS using the rapid LAMP assay (index test), the second swab was tested using enrichment culture (reference standard). Antimicrobial susceptibility testing was performed according to EUCAST guidelines. RESULTS: There were 376 concordant results, 20 discordant and four invalid LAMP results. Among discordant results, six were LAMP negative/culture positive and 14 were LAMP positive/culture negative. The sensitivity was 92.2%, specificity 95.6%, positive predictive value 83.5% and negative predictive value 98.1%. The prevalence of GBS carriage was 19.25% (77/400). Forty-eight of 77 GBS-positive women were colonized vaginally (62.3%) and 70 were colonized rectally (90.9%). Erythromycin resistance was 22.4% (17/76) and clindamycin resistance was 17.1% (13/76). CONCLUSIONS: The LAMP assay is a rapid and simple test with results available in approximately 1 h compared with 48 h for culture. The test has good sensitivity and specificity compared with enrichment culture. This test can be used for rapid antenatal GBS screening.


Assuntos
Técnicas de Amplificação de Ácido Nucleico/métodos , Reto/microbiologia , Infecções Estreptocócicas/diagnóstico por imagem , Streptococcus/genética , Vagina/microbiologia , Feminino , Humanos , Gravidez , Complicações Infecciosas na Gravidez/diagnóstico , Complicações Infecciosas na Gravidez/microbiologia , Prevalência , Estudos Prospectivos , Sensibilidade e Especificidade , Manejo de Espécimes/métodos , Infecções Estreptocócicas/microbiologia
16.
Eur J Cancer ; 103: 17-23, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30196106

RESUMO

BACKGROUND: Dose-escalation of epertinib (S-222611), a new potent oral EGFR/HER2 inhibitor, has established a recommended daily dose of 800 mg in patients with solid tumours. In this study, we have recruited a larger number of patients to assess further the safety, tolerability, pharmacokinetics (PKs) and antitumour activity. PATIENTS AND METHODS: Patients with solid tumours expressing EGFR or HER2 received a single dose of epertinib at 800 mg on Day 1 to assess PK over 7 days, followed by continuous once-daily dosing from Day 8. RESULTS: We treated 76 patients with breast (n = 27), upper gastrointestinal (GI; n = 30), head and neck (n = 12) or renal cancers (n = 7). Epertinib was well-tolerated with mostly grade I and II adverse events (AEs). The most frequent AE was diarrhoea, which was generally manageable with loperamide. The objective response rate (ORR) in patients with heavily pretreated breast and upper GI cancers was 16.0% (4 PRs) and 8.3% (1CR, 1PR), respectively. All six responding patients had HER2-positive tumours; the ORR for HER2-positive breast and upper GI cancer populations was 19.0% and 20.0%. Partial response in the brain disease of one breast cancer patient lasted 7.5 months. CONCLUSION: Once-daily dosing of epertinib at 800 mg was well-tolerated and demonstrated promising antitumour activity in patients with heavily pretreated HER2-positive breast and upper GI cancer, including those with brain metastases. EUDRACT NUMBER: 2009-017817-31.


Assuntos
Neoplasias/tratamento farmacológico , Inibidores de Proteínas Quinases/uso terapêutico , Quinazolinas/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias/patologia , Inibidores de Proteínas Quinases/farmacologia , Quinazolinas/farmacologia , Resultado do Tratamento
17.
J Inherit Metab Dis ; 30(1): 23-8, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17186413

RESUMO

We report nine new patients with malonic aciduria associated with enzyme-confirmed malonyl-CoA decarboxylase (MCD) deficiency in eight. Clinical details were available on eight, and molecular genetic characterization was obtained for nine. As for 15 previously described patients, cardinal clinical manifestations included developmental delay and cardiomyopathy; metabolic perturbations (e.g. acidosis) and seizures, however, were infrequent or not observed in our patients. For all, detection of elevated malonic acid in urine (+/- increased C3DC acylcarnitine by analysis employing tandem mass spectrometry) led to pursuit of enzyme studies. MCD activities (nmol/h PER mg protein) revealed: control (n = 22), 16.2 +/- 1.8 (SEM; range 5.7-46.2); patients (n = 8, assayed in duplicate), 1.7 +/- 0.3 (10% of parallel control; range 0.6-2.8). Molecular characterization by DNA sequence analysis and multiplex ligation-dependent probe amplification revealed nine novel mutations (c.796C>T; p.Gln266X, c.481delC; p.Leu161CysfsX18, c.1367A>C; p.Tyr456Ser, c.1319G>T; p.Ser440Ile, c.1430C>T; p.Ser477Phe, c.899G>T; p.Gly300Val, c.799-1683_949-1293del3128, and two other large genomic deletions comprising exons 1 or the complete gene) and two known mutations in the MLYCD gene. Our findings increase the number of enzyme-confirmed MCD-deficient patients by >50%, and expand our understanding of the phenotypic and molecular heterogeneity of this rare disorder.


Assuntos
Carboxiliases/deficiência , Carboxiliases/genética , Erros Inatos do Metabolismo/diagnóstico , Erros Inatos do Metabolismo/genética , Mutação , Adolescente , Criança , Pré-Escolar , Éxons , Feminino , Deleção de Genes , Humanos , Lactente , Masculino , Malonatos/urina , Erros Inatos do Metabolismo/sangue , Modelos Biológicos , Modelos Genéticos , Fenótipo , Reação em Cadeia da Polimerase
18.
Toxicol Lett ; 168(1): 1-6, 2007 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-17129690

RESUMO

Reactive oxygen species (ROS) have been implicated in various pulmonary diseases by causing direct injury to lung epithelial cells. Signalling activity of cells through transcription factors such as nuclear factor kappa B (NF-kappaB) and AP-1 have been shown to be regulated by ROS, and the release of pro-inflammatory cytokines demonstrated in the study of inflammatory disease. In this study, we examined the effect of the oxidant tert-butylhydroperoxide (tBHP) on mouse J774 macrophages and its ability to cause the release of the pro-inflammatory cytokine tumour necrosis factor alpha (TNF-alpha). The role of calcium as a signalling molecule was studied using various calcium antagonists. The role of the signalling molecule cAMP was also investigated using phosphodiesterase inhibitors PDE1 and PDE4 families. Oxidative stress was investigated in lung epithelial (A549) cells with and without calcium antagonists and PDE inhibitors with regard to their ability to modulate release of the neutrophil chemoattractant interleukin 8 (IL-8). The oxidant tBHP significantly increased the cytosolic calcium concentration in J774 macrophages, which was prevented by the PDE1 inhibitor. The production of TNF-alpha protein by J774 macrophages was mediated by a pathway involving calcium as addition of calcium antagonists inhibited the tBHP stimulated increase in the cytokine. Inhibitors of both PDE1 and PDE4 completely prevented the tBHP stimulated TNF-alpha release suggesting that the cAMP pathway may be important in the oxidant induced signalling pathway leading to gene expression of pro-inflammatory cytokines. In the presence of oxidant alone, A549 epithelial cells released significant amounts of IL-8, which was inhibited by both calcium antagonist treatment and PDE inhibition treatment. These data suggest that ROS-mediated lung inflammation could be mediated at least in part by calcium and elevated PDE activity associated with decreased cAMP in both macrophages and epithelial cells. Inhibition of these pathways may provide a route for treatment of inflammatory lung diseases.


Assuntos
Células Epiteliais/efeitos dos fármacos , Macrófagos/efeitos dos fármacos , Oxidantes/farmacologia , Estresse Oxidativo , Inibidores de Fosfodiesterase/farmacologia , terc-Butil Hidroperóxido/farmacologia , 3',5'-AMP Cíclico Fosfodiesterases/antagonistas & inibidores , 4-(3-Butoxi-4-metoxibenzil)-2-imidazolidinona/farmacologia , Animais , Cálcio/metabolismo , Bloqueadores dos Canais de Cálcio/farmacologia , Proteínas Quinases Dependentes de Cálcio-Calmodulina/antagonistas & inibidores , Linhagem Celular , Quelantes/farmacologia , Nucleotídeo Cíclico Fosfodiesterase do Tipo 1 , Nucleotídeo Cíclico Fosfodiesterase do Tipo 4 , Ácido Egtázico/análogos & derivados , Ácido Egtázico/farmacologia , Células Epiteliais/metabolismo , Interleucina-8/metabolismo , Pulmão/citologia , Macrófagos/metabolismo , Camundongos , Sulfonamidas/farmacologia , Fator de Necrose Tumoral alfa/metabolismo , Verapamil/farmacologia
19.
J Physiol Pharmacol ; 58 Suppl 5(Pt 2): 461-70, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18204159

RESUMO

To assess whether nanoparticle (NP) driven DNA damage induces the expression of proinflammatory transcription factors such as NFB and AP-1 A549, lung epithelial cells were treated with Carbon Black (CB), nanoparticulate CB (NPCB), NPCB coated with BaP (BaP-NPCB) for various times ranging from 30 min to 24 h. DNA strand break was determined by the comet assay and cell cycle status was analyzed using flow cytometry. Nuclear extracts were used for WB analysis of P approximately Ser15-p53. EMSA was used to detect DNA binding. Tested NP caused single strand breaks and significantly altered cell cycle kinetics. NF-kappaB and AP-1 DNA binding were increased at early time points (2.3 and 2.6 fold at 1 hour, respectively). Effects were also found on Ser15-p53 phosphorylation. N-acetylcysteine blocked NP driven effects. In conclusion, NPCB and BaP-NPCB induce DNA damage, activating p53, proteins related to DNA repair and proinflammatory transcription factors.


Assuntos
Dano ao DNA/fisiologia , Células Epiteliais/metabolismo , Pulmão/metabolismo , NF-kappa B/metabolismo , Nanopartículas/toxicidade , Fuligem/toxicidade , Fator de Transcrição AP-1/metabolismo , Acetilcisteína/farmacologia , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/ultraestrutura , Sobrevivência Celular/efeitos dos fármacos , DNA/metabolismo , Ensaio de Desvio de Mobilidade Eletroforética , Células Epiteliais/efeitos dos fármacos , Humanos , L-Lactato Desidrogenase/metabolismo , Pulmão/citologia , Pulmão/efeitos dos fármacos , Fosforilação , Suspensões , Proteína Supressora de Tumor p53/metabolismo
20.
J Physiol Pharmacol ; 58 Suppl 5(Pt 2): 437-44, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18204156

RESUMO

cAMP responsive element binding protein (CREB) plays an important role in transcriptional machinery. CREB signaling is altered in patients with asthma. However, the role of CREB in chronic obstructive pulmonary disease (COPD) is less clear. In the present study we assessed changes in subcellular CREB distribution and activation (CREB-P) in 35 stable COPD patients treated with formoterol (F), formoterol+budesonide (F/ICS), and formoterol+budesonide+theophylline (F/ICS/Th) b.i.d. for 4 weeks, using SDS-PAGE/WB in cytosol and nuclear extracts of induced sputum cells. The expression of CREB was increased after F/ICS in both cytosolic and nuclear fractions by about 40% and 24%, respectively (P<0.001, P<0.01), while CREB-P increased after F/ICS by about 50% (P<0.01) in both compartments. These changes were not affected by theophylline. In F/ICS-treated patients, relative accumulation of CREB in cytosol was observed. These findings indicate, that poor response to ICS therapy may be related to increased CREB-associated signaling.


Assuntos
Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/biossíntese , Citoplasma/metabolismo , Doença Pulmonar Obstrutiva Crônica/metabolismo , Albuterol/uso terapêutico , Western Blotting , Broncodilatadores/uso terapêutico , Núcleo Celular/metabolismo , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/genética , Humanos , Fosforilação , Doença Pulmonar Obstrutiva Crônica/tratamento farmacológico , Doença Pulmonar Obstrutiva Crônica/genética , Serina/metabolismo , Espirometria , Escarro/química , Escarro/metabolismo , Frações Subcelulares/metabolismo , Fatores de Transcrição
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