971 resultados para Lung diseases, interstitial
Resumo:
Rationale: Smooth muscle cells (SMCs) are a key component of tissue-engineered vessels. However, the sources by which they can be isolated are limited.
Objective: We hypothesized that a large number of SMCs could be obtained by direct reprogramming of fibroblasts, that is, direct differentiation of specific cell lineages before the cells reaching the pluripotent state.
Methods and Results: We designed a combined protocol of reprogramming and differentiation of human neonatal lung fibroblasts. Four reprogramming factors (OCT4, SOX2, KLF4, and cMYC) were overexpressed in fibroblasts under reprogramming conditions for 4 days with cells defined as partially-induced pluripotent stem (PiPS) cells. PiPS cells did not form tumors in vivo after subcutaneous transplantation in severe combined immunodeficiency mice and differentiated into SMCs when seeded on collagen IV and maintained in differentiation media. PiPS-SMCs expressed a panel of SMC markers at mRNA and protein levels. Furthermore, the gene dickkopf 3 was found to be involved in the mechanism of PiPS-SMC differentiation. It was revealed that dickkopf 3 transcriptionally regulated SM22 by potentiation of Wnt signaling and interaction with Kremen1. Finally, PiPS-SMCs repopulated decellularized vessel grafts and ultimately gave rise to functional tissue-engineered vessels when combined with previously established PiPS-endothelial cells, leading to increased survival of severe combined immunodeficiency mice after transplantation of the vessel as a vascular graft.
Conclusions: We developed a protocol to generate SMCs from PiPS cells through a dickkopf 3 signaling pathway, useful for generating tissue-engineered vessels. These findings provide a new insight into the mechanisms of SMC differentiation with vast therapeutic potential.
Resumo:
Morbidity and mortality have declined only modestly in patients with clinical acute lung injury (ALI) and acute respiratory distress syndrome (ARDS), despite extensive research into the pathophysiology. Current treatment remains primarily supportive with lung-protective ventilation and a fluid conservative strategy. Pharmacologic therapies that reduce the severity of lung injury in preclinical models have not yet been translated to effective clinical treatment options. Consequently, further research in translational therapies is needed. Cell-based therapy with mesenchymal stem cells (MSCs) is one attractive new therapeutic approach. MSCs have the capacity to secrete multiple paracrine factors that can regulate endothelial and epithelial permeability, decrease inflammation, enhance tissue repair, and inhibit bacterial growth. This review will focus on recent studies, which support the potential therapeutic use of MSCs in ALI/ARDS, with an emphasis on the role of paracrine soluble factors.
Resumo:
The human respiratory tract of individuals with normal lung function maintains a fine-tuned balance, being asymptomatically colonised by the normal microbiota in the upper airways and sterile in the lower tract. This equilibrium may be disrupted by the exposure to insults such as cigarette smoke. In the respiratory tract, the complex and noxious nature of inhaled cigarette smoke alters host-microorganisminteraction dynamics at all anatomical levels, causing infections in many cases. Moreover, continuous exposure to cigarette smoke itself causes deleterious effects on the host that can trigger the development of chronic respiratory diseases, such as chronic obstructive pulmonary disease (COPD) and lung cancer. COPD is an irreversible airflow obstruction associated with emphysema, fibrosis, mucus hypersecretion and persistent colonisation of the lower airways by opportunistic pathogens. COPD patients keep a stable (without exacerbation) but progressively worsening condition and suffer periodic exacerbations caused, in most cases, by infections. Although smoking and smoking-associated diseases are associated with a high risk of infection, most therapies aim to reduce inflammatory parameters, but do not necessarily take into account the presence of persistent colonisers. The effect of cigarette smoke on host-pathogen interaction dynamics in the respiratory tract, together with current and novel therapies, is discussed. Copyright©ERS 2012.
Resumo:
Aim: To explore the perception of palliative care provision for people with non-malignant respiratory disease from the perspective of bereaved caregivers.
Background: It is recognized that the majority of patients diagnosed with a malignant disease will have access to palliative care provision. However, it is less clear if the same standards of palliative care are available to those with non-malignant respiratory disease in Northern Ireland and the Republic of Ireland.
Design: A qualitative study based on broad interpretivism.
Methods: This research is a PhD study funded by the Department of Education and Learning in Northern Ireland (awarded February 2011). Data collection will consist of two stages; interviews with 20 bereaved caregivers of people who have died 3–18 months previously with a diagnosis of non-malignant respiratory disease and four focus groups with healthcare professionals involved in the care of this client group. This study will be carried out at four healthcare sites across the Island of Ireland. The data will be analysed using thematic content analysis. Research Ethics committee approval was obtained (March 2012).
Discussion: This research will explore the experiences of patients with Chronic Obstructive Pulmonary Disease, Interstitial Lung Disease and Bronchiectasis and their caregivers from the perspective of the bereaved caregiver. The outcomes of this study will provide a critical first step in the development of more responsive palliative care for this client group and have important implications for future practice and policy in the palliative care provided to this client group.
Resumo:
Nontypeable Haemophilus influenzae (NTHI) is an opportunistic gram-negative pathogen that causes respiratory infections and is associated with progression of respiratory diseases. Cigarette smoke is a main risk factor for development of respiratory infections and chronic respiratory diseases. Glucocorticoids, which are anti-inflammatory drugs, are still the most common therapy for these diseases. Alveolar macrophages are professional phagocytes that reside in the lung and are responsible for clearing infections by the action of their phagolysosomal machinery and promotion of local inflammation. In this study, we dissected the interaction between NTHI and alveolar macrophages and the effect of cigarette smoke on this interaction. We showed that alveolar macrophages clear NTHI infections by adhesion, phagocytosis, and phagolysosomal processing of the pathogen. Bacterial uptake requires host actin polymerization, the integrity of plasma membrane lipid rafts, and activation of the phosphatidylinositol 3-kinase (PI3K) signaling cascade. Parallel to bacterial clearance, macrophages secrete tumor necrosis factor alpha (TNF-alpha) upon NTHI infection. In contrast, exposure to cigarette smoke extract (CSE) impaired alveolar macrophage phagocytosis, although NTHI-induced TNF-alpha secretion was not abrogated. Mechanistically, our data showed that CSE reduced PI3K signaling activation triggered by NTHI. Treatment of CSE-exposed cells with the glucocorticoid dexamethasone reduced the amount of TNF-alpha secreted upon NTHI infection but did not compensate for CSE-dependent phagocytic impairment. The deleterious effect of cigarette smoke was observed in macrophage cell lines and in human alveolar macrophages obtained from smokers and from patients with chronic obstructive pulmonary disease.
Resumo:
Nitrogen is one of the most common impurities in diamond. On a substitutional site it acts as a deep donor, approximately 1.7 eV below the conduction band. Irradiation of nitrogen containing diamond and subsequent annealing creates the nitrogen vacancy centre, which has recently attracted much attention for quantum information processing application. Another possible product of irradiation and annealing of nitrogen containing diamond is interstitial nitrogen. Presumably, a mobile carbon interstitial migrates to a substitutional nitrogen to produce an interstitial nitrogen complex which may or may not be mobile. The configuration(s) of interstitial nitrogen related defects (e.g. bond centred, [001]-split) are not known. An infra-red (IR) absorption peak at 1450 cm-1 labelled H1a has been associated with an nitrogen interstitial complex. [1] Theoretical modelling suggested that this IR local mode is due to a bond centred nitrogen interstitial [2]. However, more recent modelling [3] suggests that this defect is mobile at temperatures were H1a is stable and instead assign H1a to two nitrogen atoms occupying a single lattice site in a [001]-split configuration. To date no electron paramagnetic resonance (EPR) spectra have been conclusively associated with an interstitial nitrogen defect.
In this study we present data from new EPR and optical absorption studies in combination with uniaxial stress of nitrogen interstitial related defects in electron irradiated and annealed nitrogen doped diamond. These measurements yield symmetry information about the defects allowing us to determine which of the proposed models are possible. EPR spectra of nitrogen interstitial related defects in samples isotopically enriched with 15N are reported and we show that these explain the lack of previous EPR data for these defects. Correlations between the IR absorbance and the integrated intensity of the new EPR defects are studied for varying irradiation doses and annealing temperatures.
Resumo:
Herein, we present the use of a single gold nanorod sensor for detection of diseases on an antibody-functionalized surface, based on antibody–antigen interaction and the localized surface plasmon resonance (LSPR) ?max shifts of the resonant Rayleigh light scattering spectra. By replacing the cetyltrimethylammonium bromide (CTAB), a tightly packed self-assembled monolayer of HS(CH2)11(OCH2CH2)6OCH2COOH(OEG6) has been successfully formed on the gold nanorod surface prior to the LSPR sensing, leading to the successful fabrication of individual gold nanorod immunosensors. Using prostate specific antigen (PSA) as a protein biomarker, the lowest concentration experimentally detected was as low as 111 aM, corresponding to a 2.79 nm LSPR ?max shift. These results indicate that the detection platform is very sensitive and outperforms detection limits of commercial tests for PSA so far. Correlatively, its detection limit can be equally compared to the assays based on DNA biobarcodes. This study shows that a gold nanorod has been used as a single nanobiosensor to detect antigens for the first time; and the detection method based on the resonant Rayleigh scattering spectrum of individual gold nanorods enables a simple, label-free detection with ultrahigh sensitivity.
Resumo:
Immunohistochemistry (IHC) plays a central role in the histopathological classification of diseases, including cancer. More recently, the importance of immunohistochemical staining is increasing. IHC usage in diagnostics is invaluable; however, the genetic and therapeutic significance of biomarker immunostaining has become equally relevant.
Resumo:
To compare the rejection rates of non-small cell lung cancer (NSCLC) samples obtained by differing sampling methods for testing by Sanger sequencing for epidermal growth factor receptor (EGFR) mutations. To assess the association between unsatisfactory outcomes and the quantity of DNA extracted from cytological versus histological samples.
Resumo:
RUNX3 aberrations play a pivotal role in the oncogenesis of breast, gastric, colon, skin and lung tissues. The aim of this study was to characterize further the expression of RUNX3 in lung cancers. To achieve this, a lung cancer tissue microarray (TMA), frozen lung cancer tissues and lung cell lines were examined for RUNX3 expression by immunohistochemistry, while the TMA was also examined for EGFR and p53 expression. RUNX3 promoter methylation status, and EGFR and KRAS mutation status were also investigated. Inactivation of RUNX3 was observed in 70% of the adenocarcinoma samples, and this was associated with promoter hypermethylation but not biased to EGFR/KRAS mutations. Our results suggest a central role of RUNX3 downregulation in pulmonary adenocarcinoma, which may not be dependent of other established cancer-causing pathways and may have important diagnostic and screening implications.
Resumo:
Several randomized phase III studies in advanced stage non-small cell lung cancer (NSCLC) confirmed the superior response rate and progression-free survival of using epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor as first-line therapy compared with chemotherapy in patients with activating EGFR mutations. Despite the need for EGFR mutation tests to guide first-line therapy in East Asian NSCLC, there are no current standard clinical and testing protocols.
Resumo:
Aim: To explore how older people with lung and colorectal cancer
view registered complementary therapy (CT) services in Northern
Ireland. Background: A literature review highlighted gaps around
information, access, and communication between patients and health
professionals regarding CT services. Methods: Using structured
interviews, a survey of 68 patients in one hospital and one hospice was
conducted in Belfast, Northern Ireland. Results: All respondents felt
that CT services should be better promoted and more easily
accessible to older people with cancer. Some patients were concerned
about the lack of written information provided regarding CT services,
which they believed led to poorer uptake and uncertainty regarding
the potential benefits. Others were concerned that engaging in or
disclosing CT usage might negatively affect existing relationships with
medical professionals. Conclusion: Patients should be offered high
quality written information on CT services to enable choice, improve
knowledge, and promote wider access. Increased physician education
may facilitate provision of such information.