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1.
Front Immunol ; 13: 968815, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36189218

RESUMO

Currently immunomodulatory compounds are under investigation for use in patients with cardiovascular disease, caused by atherosclerosis. These trials, using recurrent cardiovascular events as endpoint, require enrollment of large patient groups. We investigated the effect of key risk factors for atherosclerosis development, ageing and smoking, on the immune system, with the objective to identify biomarkers differentiating between human populations, and potentially serving as endpoints for future phase 1B trials with immunomodulatory compounds. Blood was collected from young healthy volunteers (aged 18-25 years, n=30), young smokers (18-25 years, n=20), elderly healthy volunteers (>60 years, n=20), heavy smokers (>45 years, 15 packyears, n=11) and patients with stable coronary artery disease (CAD) (>60 years, n=27). Circulating immune cell subsets were characterized by flow cytometry, and collected plasma was evaluated by proteomics (Olink). Clear ageing effects were observed, mostly illustrated by a lower level in CD8+ and naïve CD4+ and CD8+ T cells, with an increase in CD4+ and CD8+ effector memory T cells in elderly healthy volunteers compared to young healthy volunteers. Heavy smokers showed a more inflammatory cellular phenotype, especially a shift in Th1/Th2 ratio: higher Th1 and lower Th2 percentages compared to young healthy volunteers. A significant decrease in circulating atheroprotective oxLDL-specific IgM was found in patients with CAD compared to young healthy volunteers. Elevated pro-inflammatory and chemotactic proteins TREM1 and CCL11 were observed in elderly volunteers compared to young volunteers. In addition, heavy smokers had an increase in pro-inflammatory cytokine IL-6 and lysosomal protein LAMP3. These data show that ageing and smoking are associated with an inflammatory immunophenotype, and that heavy smokers or aged individuals may serve as potential populations for future clinical trials investigating immunomodulatory drugs targeted for cardiovascular disease.


Assuntos
Aterosclerose , Doenças Cardiovasculares , Adolescente , Adulto , Envelhecimento , Aterosclerose/metabolismo , Biomarcadores/metabolismo , Linfócitos T CD8-Positivos , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/etiologia , Doenças Cardiovasculares/metabolismo , Citocinas/metabolismo , Humanos , Imunoglobulina M/metabolismo , Interleucina-6/metabolismo , Pessoa de Meia-Idade , Fumar/efeitos adversos , Células Th1 , Receptor Gatilho 1 Expresso em Células Mieloides/metabolismo , Adulto Jovem
2.
Physiol Res ; 70(5): 815-820, 2021 11 29.
Artigo em Inglês | MEDLINE | ID: mdl-34505520

RESUMO

Transforming growth factor beta 1 (TGF-beta1) is a pro-fibrotic cytokine with a key role in wound repair and regeneration, including induction of fibroblast-to-myofibroblast transition. Genistein is a naturally occurring selective estrogen receptor modulator with promising anti-fibrotic properties. In the present study we aimed to investigate whether genistein modulates TGF-beta1 (canonical and non-canonical) signaling in normal dermal fibroblasts at the protein level (Western blot and immunofluorescence). We demonstrated that TGF-beta1 induces the myofibroblast-like phenotype in the studied fibroblast signaling via canonical (SMAD) and non-canonical (AKT, ERK1/2, ROCK) pathways. Genistein induced only ERK1/2 expression, whereas the combination of TGF-beta1 and genistein attenuated the ERK1/2 and ROCK signaling. Of note, the other studied pathways remained almost unaffected. From this point of view, genistein does not impair conversion of normal fibroblasts to myofibroblast-like cells.


Assuntos
Fibroblastos/efeitos dos fármacos , Genisteína/farmacologia , Fitoestrógenos/farmacologia , Fator de Crescimento Transformador beta1/metabolismo , Avaliação Pré-Clínica de Medicamentos , Fibroblastos/metabolismo , Humanos , Cultura Primária de Células , Transdução de Sinais/efeitos dos fármacos , Fator de Crescimento Transformador beta1/antagonistas & inibidores
3.
Brain Behav Immun ; 88: 515-528, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32305572

RESUMO

BACKGROUND AND AIMS: Following an infection, cytokines not only regulate the acute immune response, but also contribute to symptoms such as inflammatory hyperalgesia. We aimed to characterize the acute inflammatory response induced by a human endotoxemia model, and its effect on pain perception using evoked pain tests in two different dose levels. We also attempted to determine whether combining a human endotoxemia challenge with measurement of pain thresholds in healthy subjects could serve as a model to study drug effects on inflammatory pain. METHODS AND RESULTS: This was a placebo-controlled, randomized, cross-over study in 24 healthy males. Twelve subjects were administered a bolus of 1 ng/kg LPS intravenously, and twelve 2 ng/kg LPS. Before days of placebo/LPS administration, subjects completed a full study day without study drug administration, but with identical pain threshold testing. Blood sampling and evoked pain tests (electrical burst and -stair, heat, pressure, and cold pressor test) were performed pre-dose and at frequent intervals up to 10hr post-dose. Data were analysed with a repeated-measures ANCOVA. For both dose levels, LPS induced an evident acute inflammatory response, but did not significantly affect any of the pain modalities. In a post-hoc analysis, lowering of pain thresholds was observed in the first 3 h after dosing, corresponding with the peak of the acute inflammatory response around 1-3 h post-dose. CONCLUSION: Mild acute systemic inflammation, as induced by 1 ng/kg and 2 ng/kg LPS intravenous administration, did not significantly change pain thresholds in this study. The endotoxemia model in combination with evoked pain tests is not suitable to study acute inflammatory hyperalgesia in healthy males.


Assuntos
Dor , Estudos Cross-Over , Método Duplo-Cego , Desenvolvimento de Medicamentos , Endotoxemia/induzido quimicamente , Voluntários Saudáveis , Humanos , Inflamação , Lipopolissacarídeos , Masculino , Dor/tratamento farmacológico , Percepção da Dor
4.
Folia Biol (Praha) ; 66(5-6): 161-168, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-34087972

RESUMO

Rapid wound closure in extensively burned patients has remained one of the major unresolved issues of medicine. Integra® is the most widely established artificial skin, which is composed of a porous matrix of cross-linked bovine collagen and chondroitin 6-sulphate covered by a semi-permeable silicone layer. We present here a (immuno)histological study of a severely burned patient with a full-thickness burn treated with a tissue-engineered dermal template (Integra®) and split-thickness skin graft-based protocol. Immunohistochemical investigation of the artificial dermis revealed that immune cell infiltration reached its peak on day 10. Tissue immunophenotyping found an increase in CD3+ cells over the course of the study as well as CD4 and CD8 positivity on day 40, indicating remaining T-cell subpopulations. We observed weak/no infiltration of NK cells (CD56+). In conclusion, the use of bi-layer Integra® represents a feasible and safe procedure resulting in formation of non-irritating dermal substitutes.


Assuntos
Queimaduras , Pele Artificial , Animais , Queimaduras/cirurgia , Bovinos , Sulfatos de Condroitina , Humanos , Transplante de Pele , Cicatrização
5.
Folia Biol (Praha) ; 66(4): 142-147, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33745261

RESUMO

It has been shown previously that oestradiol protects the vascular network, leading to increased skin flap viability associated with Bcl-2, VEGF and FGF-2 up-regulation. We have shown that genistein, a natural selective oestrogen receptor modulator, also increases skin flap viability in rats and induces Bcl-2 expression in human umbilical vein endothelial cells. In the present study we aimed to answer the question whether genistein increases expression of Bcl-2, a potent anti-apoptotic protein, in human dermal microvascular endothelial cells (HMVEC-d) as well. Our results showed that administration of genistein induces Bcl-2 expression in a concentration-dependent manner. Cell co-treatment with genistein and anti-ER compounds (MPP, PHTPP, ICI, G-15) diminished the observed positive effect of genistein on Bcl-2 expression. The decrease in Bcl-2 expression in HMVEC-d was most prominent after co-treatment with ICI (nuclear ER antagonist/ GPR30 agonist) and PHTPP (selective ER-ß antagonist). In conclusion, genistein increases Bcl-2 expression in HMVEC-d, contributing to its protective effect on the skin flap viability. However, the question whether the mechanism is ER-specific (via ER-ß) has to be answered in further studies using a model of gene silencing or genetically modified cells.


Assuntos
Genisteína , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Células Cultivadas , Estradiol , Genisteína/farmacologia , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos
6.
Folia Biol (Praha) ; 65(1): 24-35, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31171079

RESUMO

During the last decades, plant extracts containing phytoestrogens have increasingly been used as an alternative to oestradiol hormone replacement therapy. The aim of the present study was to compare the effects of genistein with those of different phytoestrogen-containing plant extracts (from red clover flowers and soybeans) on the proliferation and differentiation of NIH-3T3, HaCaT and MCF-7 cells. Our results showed poor correlations between direct anti/pro-oxidant effects and cytotoxicity of the tested samples. In contrast, genistein showed a direct correlation between significant pro-oxidative effects at cytotoxic concentrations and almost no pro-oxidative effects at non-cytotoxic concentrations. Moreover, the tested red clover extract and genistein induced keratin-8 (luminal and prognostic marker in breast cancer) expression only in MCF-7 cells, but this effect was not seen following treatment with the soybean extract. From this point of view, the effect of consumption of phytoestrogens in oestrogen-positive breast cancer remains to be elucidated. In conclusion, our study demonstrates that various phytoestrogen- containing plant extracts and genistein are able to specifically modulate antioxidant properties and differentiation of studied cells.


Assuntos
Antioxidantes/metabolismo , Genisteína/química , Fitoestrógenos/química , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Animais , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Humanos , Queratina-8/metabolismo , Células MCF-7 , Camundongos , Células NIH 3T3
7.
Neth Heart J ; 27(10): 506-512, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31111455

RESUMO

INTRODUCTION: An increased body mass index (BMI) (>25 kg/m2) is associated with a wide range of electrocardiographic changes. However, the association between electrocardiographic changes and BMI in healthy young individuals with a normal BMI (18.5-25 kg/m2) is unknown. The aim of this study was to evaluate the association between BMI and electrocardiographic parameters. METHODS: Data from 1,290 volunteers aged 18 to 30 years collected at our centre were analysed. Only subjects considered healthy by a physician after review of collected data with a normal BMI and in sinus rhythm were included in the analysis. Subjects with a normal BMI (18.5-25 kg/m2) were divided into BMI quartiles analysis and a backward multivariate regression analysis with a normal BMI as a continuous variable was performed. RESULTS: Mean age was 22.7 ± 3.0 years, mean BMI was 22.0, and 73.4% were male. There were significant differences between the BMI quartiles in terms of maximum P-wave duration, P-wave balance, total P-wave area in lead V1, PR-interval duration, and heart axis. In the multivariate model maximum P-wave duration (standardised coefficient (SC) = +0.112, P < 0.001), P-wave balance in lead V1 (SC = +0.072, P < 0.001), heart axis (SC = -0.164, P < 0.001), and Sokolow-Lyon voltage (SC = -0.097, P < 0.001) were independently associated with BMI. CONCLUSION: Increased BMI was related with discrete electrocardiographic alterations including an increased P-wave duration, increased P-wave balance, a leftward shift of the heart axis, and decreased Sokolow-Lyon voltage on a standard twelve lead electrocardiogram in healthy young individuals with a normal BMI.

8.
Public Health ; 150: 77-83, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28646697

RESUMO

OBJECTIVES: Despite widespread vaccination programmes, pertussis remains a significant health burden in many countries. Low awareness of the disease, the high rate of asymptomatic cases in adults and difficulties with diagnosis could explain the under-reporting of pertussis. The lack of data on actual incidence constitutes an obstacle for public health authorities for the implementation of a vaccination strategy against pertussis in adults. The aim of this study was to evaluate the seroprevalence of antibodies against Bordetella pertussis infection in adults and to estimate the actual incidence of the disease compared with the reported incidence. STUDY DESIGN: Prospective, multicentre seroprevalence study. METHODS: The study was conducted in 2000 adult subjects aged ≥18 years who had not received pertussis vaccination within the last 5 years. All enrolled subjects provided a blood sample for serum testing of IgG antibodies against pertussis toxin, performed by enzyme-linked immunosorbent assay, to indicate if they had an acute infection or if they had been infected with pertussis within the last 12 months or earlier. Results were validated in accordance with the guidelines of the European Sero-epidemiology Network 2 and were expressed in ESEN units/ml. RESULTS: A positive concentration of anti-pertussis toxin antibodies, indicating previous pertussis infection, was demonstrated in 39.9% (n = 799) of all study subjects, and 0.40% (n = 8) of subjects had a concentration suggestive of a recent infection (within the last 12 months). The highest antibody seroprevalence was observed in subjects aged 18-29 years (1.46%). No cases of acute infection were detected. CONCLUSIONS: During the study period, the reported incidence of pertussis in the adult population was 0.84/100,000 inhabitants. Based on the seroprevalence results from this study, it is estimated that the actual incidence of pertussis could be as much as 699/100,000 inhabitants. The actual incidence of pertussis in adults in the Czech Republic could therefore be at least 200-fold higher than the reported incidence. These findings support the need for pertussis vaccination in the adult population.


Assuntos
Coqueluche/epidemiologia , Adolescente , Adulto , Anticorpos Antibacterianos/sangue , Bordetella pertussis/imunologia , República Tcheca/epidemiologia , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Vacina contra Coqueluche/administração & dosagem , Estudos Prospectivos , Estudos Soroepidemiológicos , Coqueluche/prevenção & controle , Adulto Jovem
9.
Neth Heart J ; 25(1): 16-23, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27752967

RESUMO

INTRODUCTION: Pulmonary vein (PV) reconnection is frequently the cause of recurrence of atrial fibrillation (AF) after ablation. The second-generation gold multi-electrode ablation (Gold-MEA) catheter has a new design possibly resulting in improved lesion formation compared with its predecessor. We aimed to determine the association between effective radiofrequency applications with the Gold-MEA catheter and outcome after AF ablation. METHODS: 50 consecutive patients with paroxysmal AF underwent Gold-MEA (PVAC GOLDTM, Medtronic Inc.) ablation. The Gold-MEA catheter was navigated to the PV ostium by fluoroscopy. Duty-cycled radiofrequency ablations were performed at all PV ostia. Lesions were considered transmural when electrode temperature was >50 °C and power >3 W for >30 seconds. After the ablation procedure, patients visited the outpatient clinic at 3­month intervals including 24-hour Holter ECGs. RESULTS: Mean age was 56 years. All PVs were acutely isolated with the Gold-MEA catheter. Procedure time was 111 ± 22 minutes, ablation time was 24 ± 6.7 minutes and fluoroscopy time was 20 ± 8.1 minutes. No procedure-related complications were observed. One year after ablation, 60 % of patients were still free of arrhythmia recurrences after a single PV isolation attempt. The number of transmural lesions was associated with arrhythmia-free survival: 25.0 % in <72 transmural lesions, 64.3 % in 72-108 transmural lesions and 71.4 % in >108 transmural lesions (p = 0.029). CONCLUSION: PV isolation can be performed successfully with the Gold-MEA catheter, with a favourable safety profile. Transmurality of lesions was associated with ablation success and may improve AF ablation success.

10.
Scand J Immunol ; 84(1): 12-9, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27104295

RESUMO

The complement system is a part of the innate immune system and is involved in recognition and clearance of pathogens and altered-self structures. The lectin pathway of the complement system is initiated when soluble pattern recognition molecules (PRMs) with collagen-like regions bind to foreign or altered self-surfaces. Associated with the collagen-like stems of these PRMs are three mannan-binding lectin (MBL)-associated serine proteases (MASPs) and two MBL-associated proteins (MAps). The most studied of the PRMs, MBL, is present in serum mainly as trimeric and tetrameric oligomers of the structural subunit. We hypothesized that oligomerization of MBL may influence both the potential to bind to micro organisms and the interaction with the MASPs and MAps, thus influencing the ability to initiate complement activation. When testing binding at 37 °C, we found higher binding of tetrameric MBL to Staphylococcus aureus (S. aureus) than trimeric and dimeric MBL. In serum, we found that tetrameric MBL was the main oligomeric form present in complexes with the MASPs and MAp44. Such preference was confirmed using purified forms of recombinant MBL (rMBL) oligomers, where tetrameric rMBL interacted stronger with all of the MASPs and MAp44, compared to trimeric MBL. As a direct consequence of the weaker interaction with the MASPs, we found that trimeric rMBL was inferior to tetrameric rMBL in activating the complement system. Our data suggest that the oligomeric state of MBL is crucial both for the binding properties and the effector function of MBL.


Assuntos
Proteínas Sanguíneas/metabolismo , Ativação do Complemento , Lectina de Ligação a Manose/metabolismo , Multimerização Proteica , Staphylococcus aureus/fisiologia , Proteínas de Bactérias/metabolismo , Lectina de Ligação a Manose da Via do Complemento , Humanos , Serina Proteases Associadas a Proteína de Ligação a Manose/metabolismo , Ligação Proteica
12.
Neth Heart J ; 23(9): 430-5, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26021618

RESUMO

Atrial fibrillation (AF) is associated with short-term mortality after ST-elevation myocardial infarction (STEMI), but there is limited data on the temporal association between AF and mortality after STEMI. A total of 830 patients were included (age: 62 ± 12 years, 76 % male). Patients with new-onset AF < 30 days after STEMI were divided among three subgroups: AF on the day of admission, AF 24-72 h and AF > 72 h after admission. Thirty-day mortality was assessed by telephone and via the municipal population registry. Twenty patients died < 30 days after admission. In 41 patients, AF was detected on the day of admission, in 14 patients 24-72 h after admission and in 18 patients > 72 h after admission. Mortality was higher in patients with AF on the day of admission (7.3 vs 2.2 %, p = 0.036) and 24-72 h after admission (14.3 vs 1.4 %, p < 0.001), but not in patients with AF > 72 h after admission (0 vs 1.1 %, p > 0.999). Age (odds ratio (OR) 1.123, p < 0.001), Killip class (adjusted OR 8.341, p < 0.001), AF on the day of admission (OR 3.585, p = 0.049) and 24-72 h after admission (OR 11.515, p = 0.003) were, amongst other variables, associated with an increased 30-day mortality. In conclusion, only new-onset incident AF during the first 72 h after admission was associated with 30-day mortality in STEMI patients.

13.
Neth Heart J ; 23(9): 451-2, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25985761

RESUMO

A 58-year-old woman with atrial fibrillation underwent laser balloon ablation at our centre. During 12 W ablation in the left superior pulmonary vein, a sudden steam pop was witnessed with displacement of the balloon catheter. Visualisation of the pulmonary vein antrum showed a red discolouration at the last ablation site.

14.
J Hum Hypertens ; 29(5): 292-5, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25339295

RESUMO

During renal sympathetic denervation (RDN), no mapping of renal nerves is performed and there is no clear end point of RDN. We hypothesized high-frequency renal nerve stimulation (RNS) may increase blood pressure (BP), and this increase is significantly blunted after RDN. The aim of this study was to determine the feasibility of RNS in patients undergoing RDN. Eight patients with resistant hypertension undergoing RDN were included. A quadripolar catheter was positioned at four different sites in either renal artery. RNS was performed during 1 min with a pacing frequency of 20 Hz. After all patients successfully underwent RDN, RNS was repeated at the site of maximum BP response before RDN in either renal artery. Mean age was 66 years. During RNS, BP increased significantly from 108/55 to 132/68 mm Hg (P < 0.001). After RDN, systolic BP response at the site of maximum response to RNS was significantly blunted (+43.1 vs +9.3 mm Hg, P = 0.002). In three patients, a systolic BP increase >10 mm Hg was observed after RDN. In conclusion, RNS resulted in an acute temporary BP increase. This response was significantly blunted after RDN. RNS may potentially serve as an end point for RDN.


Assuntos
Estimulação Elétrica/métodos , Hipertensão , Hipoglicemiantes/uso terapêutico , Rim , Simpatectomia/métodos , Idoso , Pressão Sanguínea/fisiologia , Determinação da Pressão Arterial , Cateterismo Periférico/métodos , Resistência a Medicamentos , Procedimentos Endovasculares/métodos , Estudos de Viabilidade , Feminino , Frequência Cardíaca/fisiologia , Humanos , Hipertensão/diagnóstico , Hipertensão/fisiopatologia , Hipertensão/terapia , Rim/irrigação sanguínea , Rim/inervação , Masculino , Pessoa de Meia-Idade , Artéria Renal , Resultado do Tratamento
15.
Neth Heart J ; 23(2): 96-9, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25388798

RESUMO

INTRODUCTION: The endoscopic laser balloon ablation system (EAS) is a relatively novel technique to perform pulmonary vein isolation (PVI) in the treatment of atrial fibrillation (AF). The present study aimed to report the results of the first 50 patients treated in the Netherlands with the EAS in terms of procedural characteristics and AF-free survival. METHODS: Fifty patients successfully underwent EAS PVI. Median follow-up was 17 months. Mean age was 56 years, 82 % had paroxysmal AF. RESULTS: 99 % of the pulmonary veins were successfully isolated with the EAS. Mean procedure time was 171 min and mean fluoroscopy time was 36 min. One procedure was complicated by a temporary phrenic nerve palsy (2 %). During follow-up, 58 % of patients remained free of AF without the use of antiarrhythmic drugs. CONCLUSION: PVI with EAS is associated with a low risk of complications and a medium-term AF-free survival comparable with other PVI techniques.

16.
Folia Biol (Praha) ; 60(1): 21-7, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24594053

RESUMO

We investigated whether early postnatal over-nutrition affects normal course of skin wound healing. To induce over-nutrition the litter size was adjusted on the first day after birth to four pups/nest (small litters). In parallel, as a control, normal nests of 10 pups/nest (normal litters) were used. For the wound healing experiment 30 male Sprague-Dawley rats, 15 from normal nests and 15 from small nests, were used. Two parallel full-thickness skin incisions and two full-thickness excisions were performed on the back of each rat. Samples for histological examination (excisions) and wound tensile strength measurement (incisions) were collected on days 2, 6, and 14 after surgery. Our study demonstrates that rats from the small nests had enhanced plasma levels of insulin and enhanced body weight/fat parameters. Furthermore, in small nests, rats that expressed the above-mentioned symptoms displayed slight improvement of epidermis regeneration, accelerated demarcation line formation, and increased wound tensile strength. From this point of view the small nest model used in the present experiment is helpful for exploration whether these acquired changes might be considered as a sufficient essential factor involved in the regulation of metabolic homeostasis and wound repair in juvenile obese male rats. Nevertheless, further studies need to be performed to verify the present findings also on other animal models and humans and to describe the exact underlying mechanism.


Assuntos
Obesidade/genética , Pele/patologia , Cicatrização , Ciências da Nutrição Animal , Animais , Animais Recém-Nascidos , Peso Corporal , Modelos Animais de Doenças , Homeostase , Insulina/metabolismo , Tamanho da Ninhada de Vivíparos , Masculino , Síndrome Metabólica/genética , Ratos , Ratos Sprague-Dawley , Resistência à Tração , Desmame
17.
Phys Rev Lett ; 112(7): 074501, 2014 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-24579604

RESUMO

We describe, for the first time, an experiment devoted to the study of the spatial conformation of a flexible fiber in a turbulent flow. We propose a model for the transition from rigid to flexible regimes as the intensity of turbulence is increased or the elastic energy of the fiber is decreased. This transition occurs for a fiber typical length which is observed experimentally and recovered by our analysis. We also demonstrate that the conformations of flexible fibers in a turbulent flow are analog to conformations of flexible polymers in a good solvent. This last result opens some new and creative ways to model flexible fiber distortions in turbulent flows while addressing fundamental problems in polymer dynamics.

18.
Folia Biol (Praha) ; 58(4): 135-43, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22980504

RESUMO

Tracheotomy may be associated with numerous acute and chronic complications including extensive formation of granulation tissue. The emerging functional versatility of the adhesion/growth-regulatory galectins prompted us to perform a histochemical study of wound healing using rat trachea as model. By using non-cross-reactive antibodies and the labelled tissue lectins we addressed the issue of the presence and regulation of galectin reactivity during trachea wound healing. Beside localization of high-molecular-weight keratin, wide-spectrum cytokeratin, keratins 10 and 14, α-smooth muscle actin, vimentin, fibronectin, and Sox-2, galectins -1, -2, and -3 and their reactivity profiles were measured in frozen sections of wounded and control trachea specimens 7, 14, and 28 days after trauma. A clear trend for decreased galectin-1 presence and increased reactivity for galectin-1 was revealed from day 7 to day 28. Sox-2-positive cells were present after seven days and found in the wound bed. Interestingly, several similarities were observed in comparison to skin wound healing including regulation of galectin-1 parameters.


Assuntos
Biomarcadores/metabolismo , Lectinas/metabolismo , Traqueia/fisiologia , Cicatrização/fisiologia , Animais , Adesão Celular , Modelos Animais de Doenças , Galectinas/metabolismo , Histocitoquímica , Humanos , Masculino , Ratos , Ratos Sprague-Dawley , Pele/patologia , Traqueia/patologia , Traqueostomia/efeitos adversos , Traqueotomia/efeitos adversos
19.
Clin Exp Immunol ; 169(1): 38-48, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22670777

RESUMO

The pattern-recognition molecules mannan-binding lectin (MBL) and the three ficolins circulate in blood in complexes with MBL-associated serine proteases (MASPs). When MBL or ficolin recognizes a microorganism, activation of the MASPs occurs leading to activation of the complement system, an important component of the innate immune system. Three proteins are produced from the MASP1 gene: MASP-1 and MASP-3 and MAp44. We present an assay specific for MASP-1, which is based on inhibition of the binding of anti-MASP-1-specific antibody to MASP-1 domains coated onto microtitre wells. MASP-1 was found in serum in large complexes eluting in a position corresponding to ∼600 kDa after gel permeation chromatography in calcium-containing buffer and as monomers of ∼75 kDa in dissociating buffer. The concentration of MASP-1 in donor sera (n = 105) was distributed log-normally with a median value of 11 µg/ml (range 4-30 µg/ml). Serum and citrate plasma levels were similar, while the values in ethylenediamine tetraacetic acid plasma were slightly lower and in heparin plasma were 1·5 times higher than in serum. MASP-1 was present at adult level at 1 year of age, while it was 60% at birth. In normal healthy individuals the level of MASP-1 was stable throughout a 2-month period. After induction of an acute-phase reaction by operation we found an initial short decrease, concomitant with an increase in C-reactive protein levels, followed by an increase, doubling the MASP-1 concentration after 2 days. The present data prepare the ground for studies on the associations of MASP-1 levels with disease.


Assuntos
Reação de Fase Aguda/sangue , Reação de Fase Aguda/imunologia , Lectina de Ligação a Manose da Via do Complemento/imunologia , Serina Proteases Associadas a Proteína de Ligação a Manose/análise , Serina Proteases Associadas a Proteína de Ligação a Manose/imunologia , Adulto , Fatores Etários , Animais , Western Blotting/métodos , Proteína C-Reativa/análise , Cromatografia em Gel/métodos , Neoplasias Colorretais/sangue , Humanos , Imunidade Inata/imunologia , Imunoglobulina G/isolamento & purificação , Lactente , Recém-Nascido , Lectinas/análise , Lectinas/imunologia , Lectina de Ligação a Manose/sangue , Ratos , Ratos Wistar , Ficolinas
20.
Folia Biol (Praha) ; 58(2): 75-80, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22578958

RESUMO

Non-small cell lung cancer has one of the highest mortality rates among cancer-suffering patients. It is well known that the unwanted psychotropic effects of cannabinoids (CBs) are mediated via the CB(1) receptor (R), and selective targeting of the CB(2)R would thus avoid side effects in cancer treatment. Therefore, the aim of our study was to evaluate the effect of selective CB(2)R agonist, JWH-133, on A549 cells (non-small lung cancer) and human umbilical vein endothelial cells (HUVECs). Cytotoxicity assay and DNA fragmentation assay were employed to evaluate the influence of JWH-133 (3-(1,1-dimethylbutyl)- 1-deoxy-Δ8-tetrahydrocannabinol) on investigated cancer cells. In addition, migration assay and gelatinase zymography were performed in HUVECs to asses JWH-133 anti-angiogenic activity. Our study showed that JWH-133 exerted cytotoxic effect only at the highest concentration used (10(-4) mol/l), while inhibition of colony formation was also detected at the non-toxic concentrations (10(-5)-10(-8) mol/l). JWH-133 was also found to be able to induce weak DNA fragmentation in A549 cells. Furthermore, JWH-133 at non-toxic concentrations inhibited some steps in the process of angiogenesis. It significantly inhibited endothelial cell migration after 17 h of incubation at concentrations of 10(-4)-10(-6) mol/l. In addition, JWH-133 inhibited MMP-2 secretion as assessed by gelatinase zymography. The present study demonstrates the in vitro anti-proliferative and anti-angiogenic potential of CB(2)R agonist, JWH-133, in nonsmall lung cancer cells and HUVECs. Our results generate a rationale for further in vivo efficacy studies with this compound in preclinical cancer models.


Assuntos
Canabinoides/farmacologia , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Neoplasias Pulmonares/tratamento farmacológico , Receptor CB2 de Canabinoide/agonistas , Canabinoides/metabolismo , Técnicas de Cultura de Células , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Sobrevivência Celular , Fragmentação do DNA , Humanos , Neovascularização Patológica , Receptor CB2 de Canabinoide/metabolismo , Fatores de Tempo , Cicatrização
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