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5.
Sci Rep ; 10(1): 7968, 2020 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-32409755

RESUMO

The diagnostic possibilities of multiphoton tomography (MPT) in dermatology have already been demonstrated. Nevertheless, the analysis of MPT data is still time-consuming and operator dependent. We propose a fully automatic approach based on convolutional neural networks (CNNs) to fully realize the potential of MPT. In total, 3,663 MPT images combining both morphological and metabolic information were acquired from atopic dermatitis (AD) patients and healthy volunteers. These were used to train and tune CNNs to detect the presence of living cells, and if so, to diagnose AD, independently of imaged layer or position. The proposed algorithm correctly diagnosed AD in 97.0 ± 0.2% of all images presenting living cells. The diagnosis was obtained with a sensitivity of 0.966 ± 0.003, specificity of 0.977 ± 0.003 and F-score of 0.964 ± 0.002. Relevance propagation by deep Taylor decomposition was used to enhance the algorithm's interpretability. Obtained heatmaps show what aspects of the images are important for a given classification. We showed that MPT imaging can be combined with artificial intelligence to successfully diagnose AD. The proposed approach serves as a framework for the automatic diagnosis of skin disorders using MPT.

6.
J Biomed Opt ; 25(1): 1-12, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-32003191

RESUMO

Two-photon microscopes have been successfully translated into clinical imaging tools to obtain high-resolution optical biopsies for in vivo histology. We report on clinical multiphoton coherent anti-Stokes Raman spectroscopy (CARS) tomography based on two tunable ultrashort near-infrared laser beams for label-free in vivo multimodal skin imaging. The multiphoton biopsies were obtained with the compact tomograph "MPTflex-CARS" using a photonic crystal fiber, an optomechanical articulated arm, and a four-detector-360 deg measurement head. The multiphoton tomograph has been employed to patients in a hospital with diseased skin. The clinical study involved 16 subjects, 8 patients with atopic dermatitis, 4 patients with psoriasis vulgaris, and 4 volunteers served as control. Two-photon cellular autofluorescence lifetime, second harmonic generation (SHG) of collagen, and CARS of intratissue lipids/proteins have been detected with single-photon sensitivity, submicron spatial resolution, and picosecond temporal resolution. The most important signal was the autofluorescence from nicotinamide adenine dinucleotide [NAD(P)H]. The SHG signal from collagen was mainly used to detect the epidermal-dermal junction and to calculate the ratio elastin/collagen. The CARS/Raman signal provided add-on information. Based on this view on the disease-affected skin on a subcellular level, skin areas affected by dermatitis and by psoriasis could be clearly identified. Multimodal multiphoton tomographs may become important label-free clinical high-resolution imaging tools for in vivo skin histology to realize rapid early diagnosis as well as treatment control.

.

7.
J Biomater Appl ; 33(9): 1285-1297, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30791851

RESUMO

BACKGROUND: Application of controlled in vitro techniques can be used as a screening tool for the development of new hemostatic agents allowing quantitative assessment of overall hemostatic potential. MATERIALS AND METHODS: Several tests were selected to evaluate the efficacy of cotton gauze, collagen, and oxidized regenerated cellulose for enhancing blood clotting, coagulation, and platelet activation. RESULTS: Visual inspection of dressings after blood contact proved the formation of blood clots. Scanning electron microscopy demonstrated the adsorption of blood cells and plasma proteins. Significantly enhanced blood clot formation was observed for collagen together with ß-thromboglobulin increase and platelet count reduction. Oxidized regenerated cellulose demonstrated slower clotting rates not yielding any thrombin generation; yet, led to significantly increased thrombin-anti-thrombin-III complex levels compared to the other dressings. As hemostyptica ought to function without triggering any adverse events, induction of hemolysis, instigation of inflammatory reactions, and initiation of the innate complement system were also tested. Here, cotton gauze provoked high PMN elastase and elevated SC5b-9 concentrations. CONCLUSIONS: A range of tests for desired and undesired effects of materials need to be combined to gain some degree of predictability of the in vivo situation. Collagen-based dressings demonstrated the highest hemostyptic properties with lowest adverse reactions whereas gauze did not induce high coagulation activation but rather activated leukocytes and complement.

8.
Mil Med ; 182(S1): 376-382, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-28291502

RESUMO

We hypothesized that the addition of silver nanoparticles (AgNP) to a dermal substrate would impart antibacterial properties without inhibiting the proliferation of contained cells. Our in vitro model was based on the commercial substrate, Integra. The substrate was prepared by simple immersion into 0 to 1% suspension of AgNP (75 or 200 nm diameter) followed by rinsing for 20 minutes and sterilization under an ultraviolet C lamp. A total of 107 human adipose stem cells per cubic centimeter were injected and after 1 hour, 6 × 105 keratinocytes/cm2 were seeded and cultured for up to 14 days. Constructs were evaluated using a metabolic assay (WST-1), and hematoxylin and eosin and immunoperoxidase staining. Bactericidal activity was measured using a log reduction assay against bacteria that are prevalent in burns. The presence of AgNP did not significantly change the metabolic activity of constructs after 14 days of culture, and the distribution of cells within the substrate was unchanged from the controls that did not have AgNP. Antibacterial activity of Integra containing AgNP (75 nm diameter) was concentration dependent. In conclusion, the addition of AgNP to the dermal substrate suppressed bacterial growth but did not significantly affect cell proliferation, and may represent an important property to incorporate into a future clinical skin regeneration system.


Assuntos
Antibacterianos/farmacologia , Nanopartículas/uso terapêutico , Regeneração/efeitos dos fármacos , Prata/uso terapêutico , Antibacterianos/administração & dosagem , Antibacterianos/uso terapêutico , Queimaduras/tratamento farmacológico , Sulfatos de Condroitina/administração & dosagem , Sulfatos de Condroitina/uso terapêutico , Colágeno/administração & dosagem , Colágeno/uso terapêutico , Humanos , Queratinócitos/transplante , Nanopartículas/administração & dosagem , Prata/administração & dosagem , Prata/farmacologia , Pele/lesões , Transplante Autólogo/métodos
9.
J Mater Sci Mater Med ; 27(12): 190, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27844305

RESUMO

Functionalized textiles can be used in wound management to reduce the microbial burden in the wound area, to prevent wound infections, and to avoid cross-contamination between patients. In the present study, a comprehensive in vitro approach to enable the assessment of antibacterial activity of functionalized textiles and cytotoxicity of cyclodextrin (CD)-complexes with chlorhexidine diacetate (CHX), iodine (IOD), and polihexanide (PHMB) is suggested to evaluate their properties for supporting optimal conditions for wound healing. For all ß-CD-antiseptic functionalized cotton samples a strong antibacterial effect on the Gram-positive bacteria Staphylococcus aureus and Staphylococcus epidermidis as well as on the Gram-negative bacteria Klebsiella pneumoniae and Escherichia coli was proven. In addition, ß-CD-CHX and ß-CD-PHMB were effective against the yeast Candida albicans. The growth of Pseudomonas aeruginosa could be reduced significantly by ß-CD-IOD and ß-CD-PHMB. The established comprehensive testing system for determination of biocompatibility on human HaCaT keratinocytes is suitable for obtaining robust data on cell viability, cytotoxicity and mode of cell death of the ß-CD-antiseptic-complexes. The promising results of the high antimicrobial activity of these functionalized textiles show the high potential of such materials in medical applications.


Assuntos
Anti-Infecciosos/química , Infecções Bacterianas/tratamento farmacológico , Materiais Biocompatíveis , Ciclodextrinas/química , Têxteis , Anti-Infecciosos Locais , Apoptose , Biguanidas , Candida albicans/efeitos dos fármacos , Caspase 3/metabolismo , Linhagem Celular , Sobrevivência Celular , Escherichia coli/efeitos dos fármacos , Citometria de Fluxo , Humanos , Queratinócitos/efeitos dos fármacos , Queratinócitos/microbiologia , Klebsiella pneumoniae/efeitos dos fármacos , Teste de Materiais , Testes de Sensibilidade Microbiana , Pseudomonas aeruginosa/efeitos dos fármacos , Infecções Estafilocócicas/tratamento farmacológico , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus epidermidis/efeitos dos fármacos
10.
Lab Chip ; 16(22): 4319-4325, 2016 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-27731881

RESUMO

Culturing cells at the air-liquid interface (ALI) is essential for creating functional in vitro models of lung tissues. We present the use of direct-patterned laser-treated hydrophobic paper as an effective semi-permeable membrane, ideal for ALI cell culture. The surface properties of the paper are modified through a selective CO2 laser-assisted treatment to create a unique porous substrate with hydrophilic regions that regulate fluid diffusion and cell attachment. To select the appropriate model, four promising hydrophobic films were compared with each other in terms of gas permeability and long-term strength in an aqueous environment (wet-strength). Among the investigated substrates, parchment paper showed the fastest rate of oxygen permeability (3 times more than conventional transwell cell culture membranes), with the least variation in its dry and wet tensile strengths (124 MPa and 58 MPa, remaining unchanged after 7 days of submersion in PBS).The final paper-based platform provides an ideal, robust, and inexpensive device for generating monolayers of lung epithelial cells on-chip in a high-throughput fashion for disease modelling and in vitro drug testing.


Assuntos
Técnicas de Cultura de Células/instrumentação , Papel , Mucosa Respiratória/citologia , Análise Serial de Tecidos/instrumentação , Humanos , Dispositivos Lab-On-A-Chip , Fenômenos Mecânicos , Oxigênio/metabolismo , Permeabilidade , Molhabilidade
11.
Mol Cancer Res ; 14(7): 660-71, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27097643

RESUMO

UNLABELLED: Adipose-derived stem cells (ASC) have received considerable attention in oncology because of the known direct link between obesity and cancer as well as the use of ASCs in reconstructive surgery after tumor ablation. Previous studies have documented how cancer cells commandeer ASCs to support their survival by altering extracellular matrix composition and stiffness, migration, and metastasis. This study focused on delineating the effects of ASCs and adipocytes on the self-renewal of stem/progenitor cells and hierarchy of breast epithelial cells. The immortalized breast epithelial cell line MCF10A, ductal carcinoma in situ (DCIS) cell lines MCF10DCIS.com and SUM225, and MCF10A-overexpressing SRC oncogene were examined using a mammosphere assay and flow cytometry for the effects of ASCs on their self-renewal and stem-luminal progenitor-differentiated cell surface marker profiles. Interestingly, ASCs promoted the self-renewal of all cell types except SUM225. ASC coculture or treatment with ASC conditioned media altered the number of CD49f(high)/EpCAM(low) basal/stem-like and CD49f(medium)/EpCAM(medium) luminal progenitor cells. Among multiple factors secreted by ASCs, IFNγ and hepatocyte growth factor (HGF) displayed unique actions on epithelial cell hierarchy. IFNγ increased stem/progenitor-like cells while simultaneously reducing the size of mammospheres, whereas HGF increased the size of mammospheres with an accompanying increase in luminal progenitor cells. ASCs expressed higher levels of HGF, whereas adipocytes expressed higher levels of IFNγ. As luminal progenitor cells are believed to be prone for transformation, IFNγ and HGF expression status of ASCs may influence susceptibility for developing breast cancer as well as on outcomes of autologous fat transplantation on residual/dormant tumor cells. IMPLICATIONS: This study suggests that the ratio of ASCs to adipocytes influences cancer cell hierarchy, which may impact incidence and progression. Mol Cancer Res; 14(7); 660-71. ©2016 AACR.


Assuntos
Adipócitos/patologia , Neoplasias da Mama/patologia , Mama/patologia , Células-Tronco/patologia , Diferenciação Celular/fisiologia , Linhagem Celular , Linhagem Celular Tumoral , Proliferação de Células/fisiologia , Transformação Celular Neoplásica/patologia , Feminino , Humanos
12.
J Biomater Sci Polym Ed ; 26(14): 931-46, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26135213

RESUMO

Hemocompatibility of aqueous solutions of antimicrobial 6-deoxy-6-aminoethyleneamino (AEA) cellulose with different degrees of substitution (DS, 0.54-0.92) was investigated in vitro. The AEA cellulose derivatives were synthesized by tosylation of cellulose and subsequent nucleophilic substitution with 1,2-diaminoethane. The structure was confirmed by elemental analysis as well as by FTIR and NMR spectroscopies. Markers for coagulation (thrombin generation, aPTT, PT, blood clotting, thrombocyte activation) and membrane integrity (hemolysis) were measured in human whole blood, human platelet-rich plasma, human pooled plasma, and erythrocytes suspension. AEA cellulose with a low DS of 0.54 showed the highest hemocompatibility in vitro, suggesting the possibility of biomedical applications.


Assuntos
Materiais Biocompatíveis/química , Materiais Biocompatíveis/síntese química , Coagulação Sanguínea , Celulose , Ativação Plaquetária , Espectroscopia de Ressonância Magnética Nuclear de Carbono-13 , Celulose/análogos & derivados , Celulose/síntese química , Celulose/química , Dimetil Sulfóxido/química , Relação Dose-Resposta a Droga , Eritrócitos/fisiologia , Etilenodiaminas/química , Citometria de Fluxo , Hemólise , Humanos , Teste de Materiais , Estrutura Molecular , Plasma/fisiologia , Trombina/metabolismo , Fatores de Tempo , Compostos de Tosil/química
13.
BMC Genomics ; 12: 630, 2011 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-22192797

RESUMO

BACKGROUND: Understanding how human cells in tissue culture adapt to hypothermia may aid in developing new clinical procedures for improved ischemic and hypothermic protection. Human coronary artery endothelial cells grown to confluence at 37°C and then transferred to 25°C become resistant over time to oxidative stress and injury induced by 0°C storage and rewarming. This protection correlates with an increase in intracellular glutathione at 25°C. To help understand the molecular basis of endothelial cold-adaptation, isolated proteins from cold-adapted (25°C/72 h) and pre-adapted cells were analyzed by quantitative proteomic methods and differentially expressed proteins were categorized using the DAVID Bioinformatics Resource. RESULTS: Cells adapted to 25°C expressed changes in the abundance of 219 unique proteins representing a broad range of categories such as translation, glycolysis, biosynthetic (anabolic) processes, NAD, cytoskeletal organization, RNA processing, oxidoreductase activity, response-to-stress and cell redox homeostasis. The number of proteins that decreased significantly with cold-adaptation exceeded the number that increased by 2:1. Almost half of the decreases were associated with protein metabolic processes and a third were related to anabolic processes including protein, DNA and fatty acid synthesis. Changes consistent with the suppression of cytoskeletal dynamics provided further evidence that cold-adapted cells are in an energy conserving state. Among the specific changes were increases in the abundance and activity of redox proteins glutathione S-transferase, thioredoxin and thioredoxin reductase, which correlated with a decrease in oxidative stress, an increase in protein glutathionylation, and a recovery of reduced protein thiols during rewarming from 0°C. Increases in S-adenosylhomocysteine hydrolase and nicotinamide phosphoribosyltransferase implicate a central role for the methionine-cysteine transulfuration pathway in increasing glutathione levels and the NAD salvage pathway in increasing the reducing capacity of cold-adapted cells. CONCLUSIONS: Endothelial adaptation to mild-moderate hypothermia down-regulates anabolic processes and increases the reducing capacity of cells to enhance their resistance to oxidation and injury associated with 0°C storage and rewarming. Inducing these characteristics in a clinical setting could potentially limit the damaging effects of energy insufficiency due to ischemia and prevent the disruption of integrated metabolism at low temperatures.


Assuntos
Adaptação Fisiológica , Temperatura Baixa , Endotélio/fisiologia , Proteômica , Glicólise , NAD/metabolismo , Estresse Oxidativo
14.
Pediatr Radiol ; 39(11): 1216-22, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19795114

RESUMO

BACKGROUND: Assessment of small brain lesions in children is often compromised by pulsation, flow or movement artefacts. MRI with a rotating blade-like k-space covering (BLADE, PROPELLER) can compensate for these artefacts. OBJECTIVE: We compared T2-weighted FLAIR images that were acquired with different k-space trajectories (conventional Cartesian and BLADE) to evaluate the impact of BLADE technique on the delineation of small or low-contrast brain lesions. MATERIALS AND METHODS: The subject group comprised 26 children with neurofibromatosis type 1 (NF 1), who had been routinely scanned at 1.5 T for optic pathway gliomas with both techniques and who had the typical hyperintense brain lesions seen in NF 1. Four experienced radiologists retrospectively compared unlabelled 4-mm axial images with respect to the presence of artefacts, visibility of lesions, quality of contour and contrast. RESULTS: Both techniques were comparable in depicting hyperintense lesions as small as 2 mm independent of contrast and edge definition. Pulsation and movement artefacts were significantly less common with BLADE k-space trajectory. In 7 of 26 patients (27%), lesions and artefacts were rated as indistinguishable in conventional FLAIR, but not in BLADE FLAIR images. CONCLUSION: BLADE imaging significantly improved the depiction of lesions in T2-W FLAIR images due to artefact reduction especially in the posterior fossa.


Assuntos
Artefatos , Neoplasias Encefálicas/diagnóstico , Aumento da Imagem/métodos , Imagem por Ressonância Magnética/métodos , Neurofibromatose 1/diagnóstico , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
15.
J Child Orthop ; 3(4): 313-8, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19657686

RESUMO

PURPOSE: In this retrospective study we compared the efficacy of ultrasound and radiography for determining the position of the femoral head after closed or open reduction in DDH. MATERIALS AND METHODS: The ultrasound was performed using the van Douveren technique by a transinguinal approach through a perineal window of the spica cast. Sixty-eight a.p. radiographs of the pelvis were correlated to 68 ultrasound images. RESULTS: Thirty-two radiographs were not useful for precisely determining the femoral head position, whereas the criteria described by van Douveren et al. could be identified in all ultrasound images. All ultrasound images in the study were useful and gave reliable information about the position of the femoral head. CONCLUSION: Consequently, standard radiographic documentation is no longer used as a standard in our clinic. MRI and CT are reserved for special cases. We recommend transinguinal ultrasound as a standard diagnostic method to determine the position of the femoral head in hip spica casts safely and reliably.

16.
Free Radic Biol Med ; 46(5): 680-91, 2009 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-19135523

RESUMO

Hypothermia for myocardial protection or storage of vascular grafts may damage the endothelium and impair vascular function upon reperfusion/rewarming. Catalytic iron pools and oxidative stress are important mediators of cold-induced endothelial injury. Because endothelial cells are highly adaptive, we hypothesized that hypothermic preconditioning (HPC) protects cells at 0 degrees C by a heme oxygenase-1 (HO-1) and ferritin-dependent mechanism. Storage of human coronary artery endothelial cells at 0 degrees C caused the release of lactate dehydrogenase, increases in bleomycin-detectible iron (BDI), and increases in the ratio of oxidized/reduced glutathione, signifying oxidative stress. Hypoxia increased injury at 0 degrees C but did not increase BDI or oxidative stress further. HPC at 25 degrees C for 15-72 h attenuated these changes by an amount achievable by pretreating cells with 10-20 microM deferoxamine, an iron chelator, and protected cell viability. Treating cells with hemin chloride at 37 degrees C transiently increased intracellular heme, HO-1, BDI, and ferritin. Elevated heme/iron sensitized cells to 0 degrees C but ferritin was protective. HPC increased iron maximally after 2 h at 25 degrees C and ferritin levels peaked after 15 h. HO-1 was not induced. When HPC-mediated increases in ferritin were blocked by deferoxamine, protection at 0 degrees C was diminished. We conclude that HPC-mediated endothelial protection from hypothermic injury is an iron- and ferritin-dependent process.


Assuntos
Células Endoteliais/fisiologia , Ferritinas/metabolismo , Hipotermia Induzida , Precondicionamento Isquêmico , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Temperatura Baixa/efeitos adversos , Vasos Coronários/patologia , Desferroxamina/farmacologia , Células Endoteliais/patologia , Ferritinas/fisiologia , Glutationa/análogos & derivados , Glutationa/análise , Heme Oxigenase-1/metabolismo , Humanos , Ferro/antagonistas & inibidores , Ferro/fisiologia , L-Lactato Desidrogenase/metabolismo , Traumatismo por Reperfusão Miocárdica/induzido quimicamente , Traumatismo por Reperfusão Miocárdica/enzimologia , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/fisiologia
17.
Cell Transplant ; 15(6): 499-510, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17121161

RESUMO

There is growing evidence that oxidative stress plays an important role in mediating the injury induced by hypothermia during the preservation of cells and tissues for clinical or research use. In cardiovascular allografts, endothelial cell loss or injury may lead to impaired control of vascular permeability and tone, thrombosis, and inflammation. We hypothesized that hypothermia-induced damage to the endothelium is linked to increases in intracellular catalytic iron pools and oxidative stress. In this study, bovine aortic endothelial cells and cell culture methods were used to model the response of the endothelium of cardiovascular tissues to hypothermia. Confluent cells were stored at 0 degrees C to 25 degrees C and cell damage was measured by lipid peroxidation (LPO) and lactate dehydrogenase release. Varying the bleomycin-detectible iron (BDI) in cells modulated cold-induced LPO and cell injury. In untreated cells, injury was highest at 0 degrees C and a minimum at 10 degrees C. A similar temperature-dependent trend was found in BDI levels and cell plating efficiencies. Arrhenius plots of cell killing and iron accumulation rates showed biphasic temperature dependence, with minima at 10 degrees C and matching activation energies above and below 10 degrees C. These findings imply that the mechanisms underlying the hypothermic increase in catalytic iron, oxidative stress, and cell killing are the same and that preservation of the endothelium may be optimized at temperatures above those routinely used.


Assuntos
Temperatura Baixa , Células Endoteliais/metabolismo , Células Endoteliais/patologia , Ferro/metabolismo , Estresse Oxidativo , Preservação de Tecido/métodos , Animais , Bleomicina/farmacologia , Catálise/efeitos dos fármacos , Bovinos , Morte Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Desferroxamina/farmacologia , Células Endoteliais/efeitos dos fármacos , Ferritinas/farmacologia , L-Lactato Desidrogenase/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Fatores de Tempo
18.
J Cell Biochem ; 99(3): 784-96, 2006 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-16676360

RESUMO

Ultraprofound hypothermia (< 5 degrees C) induces changes to cell membranes such as liquid-to-gel lipid transitions and oxidative stress that have a negative effect on membrane function and cell survival. We hypothesized that fatty acid substitution of endothelial cell lipids and alterations in their unsaturation would modify cell survival at 0 degrees C, a temperature commonly used during storage and transportation of isolated cells or tissues and organs used in transplantation. Confluent bovine aortic endothelial cells were treated with 18-carbon fatty acids (C18:0, C18:1n-9, C18:2n-6, or C18:3n-3), C20:5n-3 or C22:6n-3 (DHA), and then stored at 0 degrees C without fatty acid supplements. Storage of control cells caused the release of lactate dehydrogenase (LDH) and a threefold increase in lipid peroxidation (LPO) when compared to control cells not exposed to cold. Pre-treating cells with C18:0 decreased the unsaturation of cell lipids and reduced LDH release at 0 degrees C by 50%, but all mono- or poly-unsaturated fatty acids increased injury in a concentration-dependent manner and as the extent of fatty acid unsaturation increased. DHA-treatment increased cell fatty acid unsaturation and caused maximal injury at 0 degrees C, which was prevented by lipophilic antioxidants BHT or vitamin E, the iron chelator deferoxamine, and to a lesser extent by vitamin C. Furthermore, the cold-induced increase in LPO was reduced by C18:0, vitamin E, or DFO but enhanced by DHA. In conclusion, the findings implicate iron catalyzed free radicals and LPO as a predominant mechanism of endothelial cell injury at 0 degrees C, which may be reduced by increasing lipid saturation or treating cells with antioxidants.


Assuntos
Temperatura Baixa , Células Endoteliais/metabolismo , Ácidos Graxos Insaturados , Estresse Oxidativo , Animais , Antioxidantes/metabolismo , Bovinos , Células Cultivadas , Células Endoteliais/citologia , Ácidos Graxos Insaturados/química , Ácidos Graxos Insaturados/metabolismo , Peróxidos Lipídicos
20.
Am J Transplant ; 5(5): 995-1001, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15816879

RESUMO

Optimal lung preservation via flush of the pulmonary vasculature minimizes early graft failure post-lung transplantation. We hypothesized that the route of pulmonary flush has differential effects on thermal gradients in the lung and expression of inflammatory mediators. Swine underwent antegrade flush (AG) via pulmonary artery; AG/RG: antegrade + retrograde flush via pulmonary veins or AG/BA: antegrade + bronchial artery flush via bronchial artery. Temperatures were recorded in bronchial mucosa and peribronchial lymph nodes. RT-PCR was utilized to detect cytokine gene expression in the nodes. AG/BA flush resulted in greatest cooling of bronchial mucosa and lymph nodes (p < 0.001). The route of flush did not affect expression of RANTES, MCP-1, IL-8, IL-1beta, TNF-alpha or IL-6. However, expression of Gro was reduced 4-h post-preservation in all groups. Only AG/BA resulted in decreased IFN-gamma transcripts. These data show that, compared to AG or AG/RG, AG/BA flush results in the greatest cooling of lung compartments and down regulates lymph node expression of a cytokine and chemokine that have key roles in inflammation and immunity. These data suggest that pulmonary flush via AG/BA during donor harvest may be optimal to decrease the risk of early graft failure.


Assuntos
Transplante de Pulmão/métodos , Pulmão/patologia , Membrana Mucosa/patologia , Preservação de Órgãos/métodos , Preservação Biológica/métodos , Animais , Temperatura Corporal , Brônquios/patologia , Quimiocina CCL2/biossíntese , Quimiocina CCL5/biossíntese , Primers do DNA/química , Feminino , Regulação da Expressão Gênica , Sobrevivência de Enxerto , Interferon gama/biossíntese , Interferon gama/metabolismo , Interleucina-1/biossíntese , Interleucina-6/biossíntese , Interleucina-8/biossíntese , Pulmão/metabolismo , Linfonodos/patologia , Masculino , Membrana Mucosa/metabolismo , Soluções para Preservação de Órgãos , Artéria Pulmonar/patologia , Distribuição Aleatória , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Suínos , Temperatura , Fatores de Tempo , Fator de Necrose Tumoral alfa/biossíntese
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