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1.
Ann Oncol ; 34(2): 200-211, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36423745

RESUMO

BACKGROUND: Post-treatment detection of circulating tumour DNA (ctDNA) in early-stage triple-negative breast cancer (TNBC) patients predicts high risk of relapse. c-TRAK TN assessed the utility of prospective ctDNA surveillance in TNBC and the activity of pembrolizumab in patients with ctDNA detected [ctDNA positive (ctDNA+)]. PATIENTS AND METHODS: c-TRAK TN, a multicentre phase II trial, with integrated prospective ctDNA surveillance by digital PCR, enrolled patients with early-stage TNBC and residual disease following neoadjuvant chemotherapy, or stage II/III with adjuvant chemotherapy. ctDNA surveillance comprised three-monthly blood sampling to 12 months (18 months if samples were missed due to coronavirus disease), and ctDNA+ patients were randomised 2 : 1 to intervention : observation. ctDNA results were blinded unless patients were allocated to intervention, when staging scans were done and those free of recurrence were offered pembrolizumab. A protocol amendment (16 September 2020) closed the observation group; all subsequent ctDNA+ patients were allocated to intervention. Co-primary endpoints were (i) ctDNA detection rate and (ii) sustained ctDNA clearance rate on pembrolizumab (NCT03145961). RESULTS: Two hundred and eight patients registered between 30 January 2018 and 06 December 2019, 185 had tumour sequenced, 171 (92.4%) had trackable mutations, and 161 entered ctDNA surveillance. Rate of ctDNA detection by 12 months was 27.3% (44/161, 95% confidence interval 20.6% to 34.9%). Seven patients relapsed without prior ctDNA detection. Forty-five patients entered the therapeutic component (intervention n = 31; observation n = 14; one observation patient was re-allocated to intervention following protocol amendment). Of patients allocated to intervention, 72% (23/32) had metastases on staging at the time of ctDNA+, and 4 patients declined pembrolizumab. Of the five patients who commenced pembrolizumab, none achieved sustained ctDNA clearance. CONCLUSIONS: c-TRAK TN is the first prospective study to assess whether ctDNA assays have clinical utility in guiding therapy in TNBC. Patients had a high rate of metastatic disease on ctDNA detection. Findings have implications for future trial design, emphasising the importance of commencing ctDNA testing early, with more sensitive and/or frequent ctDNA testing regimes.


Assuntos
Antineoplásicos Imunológicos , DNA Tumoral Circulante , Neoplasia Residual , Neoplasias de Mama Triplo Negativas , Humanos , Biomarcadores Tumorais/sangue , Mutação , Recidiva Local de Neoplasia/sangue , Recidiva Local de Neoplasia/diagnóstico , Recidiva Local de Neoplasia/tratamento farmacológico , Recidiva Local de Neoplasia/genética , Estudos Prospectivos , Neoplasias de Mama Triplo Negativas/sangue , Neoplasias de Mama Triplo Negativas/diagnóstico , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/genética , Neoplasia Residual/sangue , Neoplasia Residual/diagnóstico , Neoplasia Residual/tratamento farmacológico , Neoplasia Residual/genética , Antineoplásicos Imunológicos/uso terapêutico , DNA Tumoral Circulante/sangue
2.
Annu Int Conf IEEE Eng Med Biol Soc ; 2021: 616-620, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34891369

RESUMO

Obstructive sleep apnea (OSA) is a common sleep disorder. Positive airway pressure (PAP) therapy is the first-line treatment, while its effectiveness is significantly limited by incomplete adherence in many patients. This work aims to find a predictive association between data from in-laboratory sleep studies during treatment (PAP titration polysomnogram, or PSG) and PAP adherence. Based on a PAP titration PSG database, we present a pipeline to develop a wavelet-based deep learning model and address two challenges. First, to tackle the problem of extremely long overnight PSG signals, it randomly draws segments and extracts features locally. The global representation for the entire signal is achieved by local feature P-norm pooling. Second, to tackle the problem of limited dataset size, the pre-trained EfficienNet-B7 is used as an unsupervised feature extractor to transfer ImageNet knowledge to PSG signals in the wavelet domain. The trained pipeline achieves 78% balanced accuracy and 83% AUC on the test set using airflow and frontal EEG signals, which, we believe, is a compelling result as a pilot study.


Assuntos
Apneia Obstrutiva do Sono , Transtornos do Sono-Vigília , Humanos , Projetos Piloto , Polissonografia , Sono , Apneia Obstrutiva do Sono/diagnóstico , Apneia Obstrutiva do Sono/terapia
3.
Anaesthesia ; 76(5): 655-664, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33399225

RESUMO

Malignant hyperthermia is defined in the International Classification of Diseases as a progressive life-threatening hyperthermic reaction occurring during general anaesthesia. Malignant hyperthermia has an underlying genetic basis, and genetically susceptible individuals are at risk of developing malignant hyperthermia if they are exposed to any of the potent inhalational anaesthetics or suxamethonium. It can also be described as a malignant hypermetabolic syndrome. There are no specific clinical features of malignant hyperthermia and the condition may prove fatal unless it is recognised in its early stages and treatment is promptly and aggressively implemented. The Association of Anaesthetists has previously produced crisis management guidelines intended to be displayed in all anaesthetic rooms as an aide memoire should a malignant hyperthermia reaction occur. The last iteration was produced in 2011 and since then there have been some developments requiring an update. In these guidelines we will provide background information that has been used in updating the crisis management recommendations but will also provide more detailed guidance on the clinical diagnosis of malignant hyperthermia. The scope of these guidelines is extended to include practical guidance for anaesthetists dealing with a case of suspected malignant hyperthermia once the acute reaction has been reversed. This includes information on care and monitoring during and after the event; appropriate equipment and resuscitative measures within the operating theatre and ICU; the importance of communication and teamwork; guidance on counselling of the patient and their family; and how to make a referral of the patient for confirmation of the diagnosis. We also review which patients presenting for surgery may be at increased risk of developing malignant hyperthermia under anaesthesia and what precautions should be taken during the peri-operative management of the patients.


Assuntos
Dantroleno/uso terapêutico , Hipertermia Maligna/tratamento farmacológico , Relaxantes Musculares Centrais/uso terapêutico , Acidose/tratamento farmacológico , Acidose/etiologia , Temperatura Corporal , Cálcio/administração & dosagem , Dióxido de Carbono/análise , Síndromes Compartimentais/tratamento farmacológico , Síndromes Compartimentais/etiologia , Coagulação Intravascular Disseminada/etiologia , Coagulação Intravascular Disseminada/terapia , Frequência Cardíaca , Humanos , Hiperpotassemia/tratamento farmacológico , Hiperpotassemia/etiologia , Hipertermia Maligna/complicações , Hipertermia Maligna/diagnóstico , Mioglobinúria/tratamento farmacológico , Mioglobinúria/etiologia , Ventilação Pulmonar , Fatores de Risco , Bicarbonato de Sódio/administração & dosagem
4.
Sleep Med ; 76: 89-97, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33129011

RESUMO

BACKGROUND: Suboptimal sleep, including insufficient/long sleep duration and poor sleep quality, is a risk factor for cardiovascular disease (CVD) common but there is little information among African Americans, a group with a disproportionate CVD burden. The current study examined the association between suboptimal sleep and incident CVD among African Americans. METHODS: This study included 4,522 African Americans without CVD at baseline (2000-2004) of the Jackson Heart Study (JHS). Self-reported sleep duration was defined as very short (<6 h/night), short (6 h/night), recommended (7-8 h/night), and long (≥9 h/night). Participants' self-reported sleep quality was defined as "high" and "low" quality. Suboptimal sleep was defined by low quality sleep and/or insufficient/long sleep duration. Incident CVD was a composite of incident coronary heart disease and stroke. Associations between suboptimal sleep and incident CVD were examined using Cox proportional hazards models over 15 follow-up years with adjustment for predictors of CVD risk and obstructive sleep apnea. RESULTS: Sample mean age was 54 years (SD = 13), 64% female and 66% reported suboptimal sleep. Suboptimal sleep was not associated with incident CVD after covariate adjustment [HR(95% CI) = 1.18(0.97-1.46)]. Long [HR(95%CI) = 1.32(1.02-1.70)] and very short [HR(95% CI) = 1.56(1.06-2.30)] sleep duration were associated with incident CVD relative to recommended sleep duration. Low quality sleep was not associated with incident CVD (p = 0.413). CONCLUSIONS: Long and very short self-reported sleep duration but not self-reported sleep quality were associated with increased hazard of incident CVD.


Assuntos
Negro ou Afro-Americano , Doenças Cardiovasculares , Sono , Adulto , Idoso , Doenças Cardiovasculares/epidemiologia , Feminino , Humanos , Incidência , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Fatores de Tempo , Estados Unidos
5.
Anaesthesia ; 74(10): 1211-1214, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31347139
8.
Oncogene ; 36(36): 5134-5144, 2017 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-28481875

RESUMO

Toll-like receptors (TLRs) are key regulators of innate immune responses, and their dysregulation is observed in numerous inflammation-associated malignancies, including gastric cancer (GC). However, the identity of specific TLRs and their molecular targets which promote the pathogenesis of human GC is ill-defined. Here, we sought to determine the clinical utility of TLR2 in human GC. TLR2 mRNA and protein expression levels were elevated in >50% of GC patient tumors across multiple ethnicities. TLR2 was also widely expressed among human GC cell lines, and DNA microarray-based expression profiling demonstrated that the TLR2-induced growth responsiveness of human GC cells corresponded with the up-regulation of six anti-apoptotic (BCL2A1, BCL2, BIRC3, CFLAR, IER3, TNFAIP3) and down-regulation of two tumor suppressor (PDCD4, TP53INP1) genes. The TLR2-mediated regulation of these anti-apoptotic and tumor suppressor genes was also supported by their increased and reduced expression, respectively, in two independent genetic GC mouse models (gp130F/F and Gan) characterized by high tumor TLR2 expression. Notably, enrichment of this TLR2-regulated gene signature also positively correlated with augmented TLR2 expression in human GC tumors, and served as an indicator of poor patient survival. Furthermore, treatment of gp130F/F and cell line-derived xenograft (MKN1) GC mouse models with a humanized anti-TLR2 antibody suppressed gastric tumor growth, which was coincident with alterations to the TLR2-driven gene signature. Collectively, our study demonstrates that in the majority of GC patients, elevated TLR2 expression is associated with a growth-potentiating gene signature which predicts poor patient outcomes, thus supporting TLR2 as a promising therapeutic target in GC.


Assuntos
Biomarcadores Tumorais/metabolismo , Proliferação de Células , Perfilação da Expressão Gênica , Neoplasias Gástricas/patologia , Receptor 2 Toll-Like/metabolismo , Animais , Apoptose , Biomarcadores Tumorais/genética , Feminino , Humanos , Camundongos , Camundongos Endogâmicos NOD , Invasividade Neoplásica , Estadiamento de Neoplasias , Prognóstico , Neoplasias Gástricas/genética , Neoplasias Gástricas/metabolismo , Taxa de Sobrevida , Receptor 2 Toll-Like/genética , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
9.
Bioresour Technol ; 242: 218-226, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28343863

RESUMO

Sustainability of a bioenergy project depends on precise assessment of biomass resource, planning of cost-effective logistics and evaluation of possible environmental implications. In this context, this paper reviews the role and applications of geo-spatial tool such as Geographical Information System (GIS) for precise agro-residue resource assessment, biomass logistic and power plant design. Further, application of Life Cycle Assessment (LCA) in understanding the potential impact of agro-residue bioenergy generation on different ecosystem services has also been reviewed and limitations associated with LCA variability and uncertainty were discussed. Usefulness of integration of GIS into LCA (i.e. spatial LCA) to overcome the limitations of conventional LCA and to produce a holistic evaluation of the environmental benefits and concerns of bioenergy is also reviewed. Application of GIS, LCA and spatial LCA can help alleviate the challenges faced by ambitious bioenergy projects by addressing both economics and environmental goals.


Assuntos
Biocombustíveis , Ecossistema , Sistemas de Informação Geográfica , Biomassa , Meio Ambiente
11.
Anaesthesia ; 72(3): 379-390, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28045209

RESUMO

Pre-hospital emergency anaesthesia with oral tracheal intubation is the technique of choice for trauma patients who cannot maintain their airway or achieve adequate ventilation. It should be carried out as soon as safely possible, and performed to the same standards as in-hospital emergency anaesthesia. It should only be conducted within organisations with comprehensive clinical governance arrangements. Techniques should be straightforward, reproducible, as simple as possible and supported by the use of checklists. Monitoring and equipment should meet in-hospital anaesthesia standards. Practitioners need to be competent in the provision of in-hospital emergency anaesthesia and have supervised pre-hospital experience before carrying out pre-hospital emergency anaesthesia. Training programmes allowing the safe delivery of pre-hospital emergency anaesthesia by non-physicians do not currently exist in the UK. Where pre-hospital emergency anaesthesia skills are not available, oxygenation and ventilation should be maintained with the use of second-generation supraglottic airways in patients without airway reflexes, or basic airway manoeuvres and basic airway adjuncts in patients with intact airway reflexes.


Assuntos
Anestesia , Serviços Médicos de Emergência , Humanos , Manuseio das Vias Aéreas/normas , Anestesia/métodos , Anestesia/normas , Anestesiologia/educação , Anestesiologia/instrumentação , Competência Clínica , Sedação Consciente/métodos , Sedação Consciente/normas , Educação de Pós-Graduação em Medicina/normas , Serviços Médicos de Emergência/organização & administração , Serviços Médicos de Emergência/normas , Intubação Intratraqueal/métodos , Intubação Intratraqueal/normas , Irlanda , Monitorização Fisiológica/métodos , Monitorização Fisiológica/normas , Transporte de Pacientes/normas , Reino Unido , Ferimentos e Lesões/terapia
12.
Rev Sci Tech ; 36(2): 639-645, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30152456

RESUMO

The World Organisation for Animal Health (OIE) plays an important leadership role in global efforts to prevent, detect and respond to infectious disease threats. Since 1924, the OIE has helped Member Countries to prevent the spread of animal diseases, while facilitating safe agricultural trade. In recent years, the OIE has also increasingly focused on the biosecurity objectives of preventing unauthorised access to and loss, theft, misuse or diversion of dangerous pathogens, including their intentional release. Preventing the intentional introduction of animal disease is critical not only because of the significant economic impact that animal diseases can have on a nation's economy, but also because a number of animal diseases can affect humans. Over 60% of human diseases are of animal origin. Therefore, the OIE, working in conjunction with its partner organisations, the Food and Agriculture Organization of the United Nations and the World Health Organization, has become a leading international organisation for the control of global infectious disease in humans as well as in animals.


L'Organisation mondiale de la santé animale (OIE) joue un rôle de chef de file dans les efforts mobilisés à l'échelle mondiale pour la prévention des menaces liées aux maladies infectieuses, leur détection et la réponse qui y est apportée. Depuis sa création en 1924, l'OIE aide ses Pays membres à prévenir la propagation des maladies animales tout en facilitant l'accès sans risque de leurs productions agricoles aux marchés internationaux. Depuis quelques années, l'OIE porte une attention accrue aux objectifs de biosûreté, c'est-à-dire l'ensemble des mesures prises pour prévenir l'accès sans autorisation, la perte, le vol, l'utilisation abusive ou l'emploi détourné d'agents pathogènes dangereux ainsi que leur libération délibérée. La prévention de l'introduction intentionnelle de maladies animales est un impératif majeur, non seulement parce que ces maladies ont un impact économique important sur l'économie d'un pays, mais aussi parce qu'un certain nombre d'entre elles affectent également l'être humain. En effet, plus de 60 % des maladies humaines sont d'origine animale. L'OIE, qui œuvre sur ces questions aux côtés de ses organisations partenaires (l'Organisation des Nations Unies pour l'alimentation et l'agriculture et l'Organisation mondiale de la santé), est devenue l'organisation phare dans le domaine de la lutte contre les maladies infectieuses dans le monde, tant humaines qu'animales.


La Organización Mundial de Sanidad Animal (OIE) cumple una importante función a la cabeza de las actividades mundiales para prevenir y detectar amenazas infecciosas y responder a ellas. Desde 1924, la OIE viene ayudando a sus Países Miembros a prevenir la propagación de enfermedades animales, facilitando al mismo tiempo un comercio agrícola seguro. De unos años a esta parte, también presta cada vez más atención a los objetivos de seguridad biológica consistentes en impedir el acceso no autorizado a patógenos peligrosos, así como su pérdida, robo, utilización indebida o sustracción, y en particular su liberación intencionada. La prevención de la introducción deliberada de enfermedades animales es fundamental no solo porque las enfermedades animales pueden perjudicar sustancialmente la economía de una nación, sino además porque muchas de esas patologías también pueden afectar al ser humano. Más del 60% de las enfermedades humanas son de origen animal. De ahí que a día de hoy la OIE, trabajando junto con otras organizaciones colaboradoras, a saber, la Organización de las Naciones Unidas para la Alimentación y la Agricultura y la Organización Mundial de la Salud, sea una de las principales instancias que obran por el control de las enfermedades infecciosas de personas y animales a escala planetaria.


Assuntos
Saúde Global/normas , Medicina Veterinária/organização & administração , Doenças dos Animais/prevenção & controle , Bem-Estar do Animal , Animais , Comércio , Surtos de Doenças/prevenção & controle , Humanos , Agências Internacionais , Cooperação Internacional , Internacionalidade , Zoonoses/prevenção & controle
13.
Oncogene ; 36(21): 3059-3066, 2017 05 25.
Artigo em Inglês | MEDLINE | ID: mdl-27893707

RESUMO

Lung cancer is the leading cause of cancer death worldwide, and is frequently associated with the devastating paraneoplastic syndrome of cachexia. The potent immunomodulatory cytokine interleukin (IL)-6 has been linked with the development of lung cancer as well as cachexia; however, the mechanisms by which IL-6 promotes muscle wasting in lung cancer cachexia are ill-defined. In this study, we report that the gp130F/F knock-in mouse model displaying hyperactivation of the latent transcription factor STAT3 via the common IL-6 cytokine family signalling receptor, gp130, develops cachexia during Kras-driven lung carcinogenesis. Specifically, exacerbated weight loss, early mortality and reduced muscle and adipose tissue mass were features of the gp130F/F:KrasG12D model, but not parental KrasG12D mice in which STAT3 was not hyperactivated. Gene expression profiling of muscle tissue in cachectic gp130F/F:KrasG12D mice revealed the upregulation of IL-6 and STAT3-target genes compared with KrasG12D muscle tissue. These cachectic features of gp130F/F:KrasG12D mice were abrogated upon the genetic normalization of STAT3 activation or ablation of IL-6 in gp130F/F:KrasG12D:Stat3-/+ or gp130F/F:KrasG12D:Il6-/- mice, respectively. Furthermore, protein levels of the soluble IL-6 receptor (sIL-6R), which is the central facilitator of IL-6 trans-signalling, were elevated in cachectic muscle from gp130F/F:KrasG12D mice, and the specific blockade of IL-6 trans-signalling, but not classical signalling, with an anti-IL-6R antibody ameliorated cachexia-related characteristics in gp130F/F:KrasG12D mice. Collectively, these preclinical findings identify trans-signalling via STAT3 as the signalling modality by which IL-6 promotes muscle wasting in lung cancer cachexia, and therefore support the clinical evaluation of the IL-6 trans-signalling/STAT3 axis as a therapeutic target in advanced lung cancer patients presenting with cachexia.


Assuntos
Adenocarcinoma/complicações , Caquexia/prevenção & controle , Genes ras/fisiologia , Interleucina-6/antagonistas & inibidores , Neoplasias Pulmonares/complicações , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/genética , Adenocarcinoma/patologia , Adenocarcinoma de Pulmão , Animais , Caquexia/etiologia , Caquexia/patologia , Transformação Celular Neoplásica/genética , Modelos Animais de Doenças , Feminino , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Masculino , Camundongos , Camundongos Transgênicos , Fator de Transcrição STAT3/antagonistas & inibidores , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais/efeitos dos fármacos
14.
Anaesthesia ; 72(1): 63-72, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27785790

RESUMO

Here, we describe proof of concept of a novel method for delivering volatile anaesthetics, where the liquid anaesthetic (sevoflurane or isoflurane) is formulated into an emulsion that is contained in a compact, lightweight device through which carrier gas flows. Release of anaesthetic is achieved by stirring of the formulation, allowing controlled and responsive release of anaesthetic at a variety of fixed flow rates between 0.5 l.min-1 and 5 l.min-1 , with ventilated, non-ventilated and draw-over breathing systems. Anaesthetic release was evaluated using target anaesthetic concentrations ranging from 0.5% v/v to 8% v/v to mimic those typically required for induction and maintenance of anaesthesia, and lower concentrations suitable for sedation. Under all conditions, output could be maintained within 0.1% v/v of the intended setting, and the device could deliver a controlled level of anaesthetic for at least 60 min, with compensation for different ambient temperatures (10-30 °C) and carrier gas flow rates. This device offers a simple, inexpensive method of delivering safe concentrations of volatile anaesthetics for a wide range of applications.


Assuntos
Anestesia por Inalação/instrumentação , Anestésicos Inalatórios/administração & dosagem , Sistemas de Liberação de Medicamentos/instrumentação , Administração por Inalação , Esquema de Medicação , Emulsões , Desenho de Equipamento , Humanos , Isoflurano/administração & dosagem , Nebulizadores e Vaporizadores , Estudo de Prova de Conceito , Sevoflurano/administração & dosagem
15.
Mol Ecol ; 25(16): 3865-83, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27357267

RESUMO

Population divergence in geographic isolation is due to a combination of factors. Natural and sexual selection may be important in shaping patterns of population differentiation, a pattern referred to as 'isolation by adaptation' (IBA). IBA can be complementary to the well-known pattern of 'isolation by distance' (IBD), in which the divergence of closely related populations (via any evolutionary process) is associated with geographic isolation. The barn swallow Hirundo rustica complex comprises six closely related subspecies, where divergent sexual selection is associated with phenotypic differentiation among allopatric populations. To investigate the relative contributions of selection and geographic distance to genome-wide differentiation, we compared genotypic and phenotypic variation from 350 barn swallows sampled across eight populations (28 pairwise comparisons) from four different subspecies. We report a draft whole-genome sequence for H. rustica, to which we aligned a set of 9493 single nucleotide polymorphisms (SNPs). Using statistical approaches to control for spatial autocorrelation of phenotypic variables and geographic distance, we find that divergence in traits related to migratory behaviour and sexual signalling, as well as geographic distance, together explain over 70% of genome-wide divergence among populations. Controlling for IBD, we find 42% of genomewide divergence is attributable to IBA through pairwise differences in traits related to migratory behaviour and sexual signalling alone. By (i) combining these results with prior studies of how selection shapes morphological differentiation and (ii) accounting for spatial autocorrelation, we infer that morphological adaptation plays a large role in shaping population-level differentiation in this group of closely related populations.


Assuntos
Evolução Biológica , Genética Populacional , Seleção Genética , Andorinhas/genética , Animais , Genoma , Geografia , Fenótipo , Isolamento Reprodutivo
17.
J Colloid Interface Sci ; 459: 175-182, 2015 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-26291573

RESUMO

Magnetic nanoparticles are the next tool in medical diagnoses and treatment in many different biomedical applications, including magnetic hyperthermia as alternative treatment for cancer and bacterial infections, as well as the disruption of biofilms. The colloidal stability of the magnetic nanoparticles in a biological environment is crucial for efficient delivery. A surface that can be easily modifiable can also improve the delivery and imaging properties of the magnetic nanoparticle by adding targeting and imaging moieties, providing a platform for additional modification. The strategy presented in this work includes multiple nitroDOPA anchors for robust binding to the surface tied to the same polymer backbone as multiple poly(ethylene oxide) chains for steric stability. This approach provides biocompatibility and enhanced stability in fetal bovine serum (FBS) and phosphate buffer saline (PBS). As a proof of concept, these polymer-particles complexes were then modified with a near infrared dye and utilized in characterizing the integration of magnetic nanoparticles in biofilms. The work presented in this manuscript describes the synthesis and characterization of a nontoxic platform for the labeling of near IR-dyes for bioimaging.


Assuntos
Biofilmes , Di-Hidroxifenilalanina/química , Corantes Fluorescentes/química , Legionella pneumophila , Nanopartículas/química , Polietilenoglicóis/química , Animais , Bovinos , Legionella pneumophila/citologia , Legionella pneumophila/fisiologia , Camundongos , Microscopia de Fluorescência
19.
Oncogene ; 34(12): 1510-9, 2015 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-24727895

RESUMO

Interleukin (IL)-6 family cytokines signal exclusively via the gp130 coreceptor, and are implicated in smoking-associated lung cancer, the most lethal cancer worldwide. However, the role of gp130 signalling pathways in transducing the carcinogenic effects of tobacco-related compounds is ill-defined. Here, we report that lung tumourigenesis induced by the potent tobacco carcinogen 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (Nicotine-derived Nitrosamine Ketone; NNK) is suppressed in gp130(F/F) knock-in mice characterized by the contrasting gp130-dependant hypoactivation of extracellular signal-regulated kinase mitogen-activated protein kinase (ERK MAPK) and phosphatidylinositol 3-kinase/Akt, and hyperactivation of signal transducer and activator of transcription (STAT)3 signalling cascades. Specifically, in response to NNK, the absolute number and size of lung lesions in gp130(F/F) mice were significantly reduced compared with gp130(+/+) littermate controls, and associated with lower cellular proliferation without any alteration to the level of apoptosis in gp130(F/F) lung tumours. At the molecular level, reduced activation of ERK MAPK, but not Akt, was observed in lung tumours of gp130(F/F) mice, and corresponded with impaired expression of several tumour suppressor genes (for example, Trp53, Tsc2). Notably, STAT3 was not activated in the lungs of gp130(+/+) mice by NNK, and genetic normalization of STAT3 activation in gp130(F/F):Stat3(-/+) mice had no effect on NNK-induced tumourigenesis. The expression of tumour suppressor genes was reduced in tumours from current versus never-smoking lung cancer patients, and in vitro pharmacological inhibition of ERK MAPK signalling in human lung cancer cells abrogated NNK-induced downmodulation of tumour suppressor gene expression. Among IL-6 cytokine family members, IL-6 gene expression was specifically upregulated by NNK in vitro and in vivo, and inversely correlated with tumour suppressor gene expression. Collectively, our data reveal that a key molecular mechanism by which NNK promotes tumour cell proliferation during tobacco carcinogen-induced lung carcinogenesis is via upregulation of IL-6 and the preferential usage of gp130-dependant ERK MAPK signalling to downmodulate tumour suppressor gene expression.


Assuntos
Carcinógenos/metabolismo , Carcinoma Pulmonar de Células não Pequenas/patologia , Neoplasias Pulmonares/patologia , Sistema de Sinalização das MAP Quinases , Nitrosaminas/efeitos adversos , Animais , Carcinoma Pulmonar de Células não Pequenas/induzido quimicamente , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Linhagem Celular , Proliferação de Células , Receptor gp130 de Citocina/genética , Receptor gp130 de Citocina/metabolismo , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Interleucina-6/metabolismo , Neoplasias Pulmonares/induzido quimicamente , Neoplasias Pulmonares/metabolismo , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Masculino , Camundongos , Nitrosaminas/metabolismo
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