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Análise da expressão e atividade de receptores ativados por proteases em plaquetas de pacientes com hipertensão arterial pulmonar / Platelet protease-activated receptors expression and activity in patients with pulmonary arterial hypertensionJoão Henrique de Carvalho 07 April 2009 (has links)
A hipertensão arterial pulmonar é uma síndrome clínica e hemodinâmica, caracterizada pelo aumento de resistência vascular na microcirculação. A vasoconstrição presente na doença ocorre principalmente devido à disfunção endotelial, induzindo a um estado pró-trombótico onde a participação das plaquetas é inequívoca. A trombina, principal agonista da ativação plaquetária, exerce seus efeitos nas células por meio de receptores ativados por proteases. Através da citometria de fluxo, este trabalho teve por objetivo analisar (1) a expressão do receptor ativado por protease do tipo 1 (PAR-1) na membrana de plaquetas, em seu estado íntegro ou clivado, (2) a atividade, mediante a formação de agregados entre plaquetas e leucócitos e, plaquetas e monócitos após estímulo de receptores ativados por proteases, além (3) da expressão de selectina-P na membrana plaquetária após estimulação. Foram estudados 30 pacientes portadores de hipertensão arterial pulmonar sob tratamento ambulatorial no Instituto do Coração da Faculdade de Medicina da Universidade de São Paulo. A idade destes pacientes variou de 11 a 78 anos, e a média da pressão sistólica da artéria pulmonar foi de 89+29 mmHg. Em 30% dos pacientes, o número de plaquetas esteve abaixo de 150x103/l, e em 40%, o nível do hematócrito apresentou-se acima de 50%. No presente estudo, não foi observada diferença significante na expressão do PAR-1 íntegro em plaquetas de pacientes comparativamente aos controles (p = 0,2). Em contrapartida, as plaquetas dos pacientes apresentaram menor quantidade de receptor clivado (p = 0,01), sugerindo internalização destes receptores. Com relação à avaliação da atividade de PAR-1 através da formação de agregados entre plaquetas e leucócitos e, plaquetas e monócitos após estimulação por agentes capazes de atuar sobre o receptor de trombina, não foram observadas diferenças entre pacientes e controles, ou seja, em ambos os casos houve a formação de agregados (p = 0,2 e p = 0,4, respectivamente). Em relação aos leucócitos, o SFLLRN, estimulou o receptor independentemente do seu estado, íntegro ou clivado, nos pacientes (p < 0,05), enquanto que nos indivíduos normais, a resposta só foi observada quando o receptor íntegro foi estimulado por trombina (p < 0,05). Tanto nos pacientes estudados, como nos controles, a estimulação do PAR-1 plaquetário, promoveu aumento da expressão de selectina-P na superfície plaquetária (p < 0,0001), embora não houvesse diferença entre os grupos (p = 0,9). Estes resultados demonstram que as plaquetas dos pacientes não são refratárias à liberação de seu conteúdo granular, e encontram-se aptas a responder aos estímulos tanto quanto as plaquetas dos controles. Este estudo reforça a importância da terapia antiplaquetária em pacientes com hipertensão arterial pulmonar. / Pulmonary hypertension is a clinical and hemodynamic syndrome, characterized by the increase of vascular resistance in lungs, generally through various mechanisms, involving vasoconstriction and remodeling of the arterial wall. Endothelial dysfunction in pulmonary arterial hypertension leads to a prothrombotic status, in which platelet participation seems to be unequivocal. Thrombin is the most potent platelet activator and exerts its effects on cells, through protease-activated receptors. Flow cytometry procedure was employed to assess (1) platelet protease-activated receptor 1 (PAR-1) expression, in both uncleaved and cleaved forms, (2) PAR-1 activity, through platelet-leukocyte and platelet-monocyte aggregates formation in response to the thrombin receptor stimulus, and finally (3) platelet P-selectin expression after stimulus. Thirty patients with pulmonary arterial hypertension (age 11 to 78 years) under treatment at the Heart Institute, University of São Paulo were enrolled. The systolic pulmonary arterial pressure was 89+29 mmHg. The platelet count was < 150x103/l in 30% of the patients, and the hematocrit level was > 50% in 40% of the patients. In the present study, there was no relevant difference in the level of intact platelet protease-activated receptor 1 expression in patients and controls (p = 0.2). On the other hand, the expression of cleaved receptors was decreased in patients (p = 0.01) platelets, what suggests internalization. There was no difference on platelet-leukocyte, and platelet-monocyte aggregates in response to the thrombin receptor stimulus between patients and controls, in other words, in both cases there was the aggregates formation (p = 0.2). However, aggregates formation in patients appeared to occur predominately in response to an agent (SFLLRN) capable to stimulate the receptor, independent of its state, intact or cleaved (p < 0.05). Otherwise, in healthy individuals, the response occurred especially when the intact receptor was stimulated by thrombin (p < 0.05). In these patients, similarly to the controls, platelet protease-activated receptor 1 stimulation induced membrane P-selectin expression (p < 0.001), although there was no difference between the groups (p = 0.9). These findings suggest that platelets from patients are not refractory to its granular content secretion and are capable to respond to stimulus as the controls platelets. This study re-enforce the importance of anti platelet therapy in pulmonary arterial hypertension patients.
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mTOR Inhibitors and Calcineurin Inhibitors Do Not Affect Adhesion Molecule Expression of Human Macro- and Microvascular Endothelial CellsLehle, Karla, Schreml, Stephan, Kunz-Schughart, Leoni A., Rupprecht, Leopold, Birnbaum, Dietrich E., Schmid, Christof, Preuner, Jürgen G. January 2008 (has links)
We examined the effect of cyclosporin A, tacrolimus, sirolimus and everolimus on the cell growth, viability, proliferation, expression of cellular adhesion molecules (CAM) and leukocyte (PBMC) binding of human macrovascular (coronary artery, saphenous vein) and microvascular endothelial cells (EC). Tacrolimus did not affect EC integrity, growth or expression of CAM. Exclusively, EC from the coronary arteries showed a reduced cellular growth (about 30%) under cyclosporin A and tacrolimus treatment. In contrast, treatment with mTOR inhibitors reduced EC proliferative activity by about 40%, independently of the EC origin. No induction of apoptosis (caspase-3/7 activity) or cytotoxicity (MTS test) was observed. Long-term treatment with high concentrations of sirolimus and everolimus did not enhance the expression of CAM. Stimulation with tumor necrosis factor significantly increased the expression of CAM, independently of the drugs used. None of the mTOR inhibitors influenced the tumor necrosis factor-induced expression of CAM, whereas adhesion of PBMC increased significantly, as described by other papers. In summary, neither calcineurin inhibitors nor mTOR inhibitors activate human micro- and macrovascular EC. Therefore, the investigated drugs are unlikely to contribute to EC activation during transplant-associated vasculopathy. / Dieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG-geförderten) Allianz- bzw. Nationallizenz frei zugänglich.
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Odnos inflamatornih biomarkera endotelne disfunkcije i ateroskleroze kod hiperalimentacione gojaznosti / Association between inflammatory biomarkers of endothelial dysfunction and atherosclerosis in obesityIlinčić Branislava 24 November 2015 (has links)
<p>UVOD: Gojaznost je hronično, multifaktorijalno i kompleksno oboljenje povezano sa povećanim rizikom od aterosklerotskih kardiovaskularnih bolesti (KVB). Disfunkcija vaskularnog endotela predstavlja rani događaj u patofiziološkom kontinuumu aterosklerotskog procesa, a produženo izlaganje vaskularnog endotela faktorima rizika za aterosklerozu udruženim sa gojaznosti (insulinska rezistencija, dislipidemija, proinflamatorno/protrombozno stanje), može doprineti procesima aktivacije/disfunkcije endotela i progresiji ateroskleroze u supkliničku, odnosno kliničku formu bolesti. CILJ: Uporediti koncentracije solubilne forme adhezionih molekula – intracelularnog adhezivnog molekula –1 (sICAM–1) i E selektina (sE–selektin), između ispitanika sa hiperalimentacionim tipom gojaznosti i normalno uhranjenih zdravih ispitanika, kao i utvrditi eventualno postojanje razlika u koncentraciji sICAM–1 i sE–selektina između ispitanika kod kojih je merenjem debljine kompleksa intima medija karotidne arterije (IMK) uočen supklinički stadijum ateroskleroze i ispitanika koji imaju normalnu debljinu IMK. Ispitati povezanost parametara telesne kompozicije (ukupne masne mase tela i masne mase abdominalnih depoa), cirkulišućih koncentracija biomarkera disfunkcije vaskularnog endotela (sICAM–1 i sE–selektina) i IMK kod ispitanika sa hiperalimentacionim tipom gojaznosti. MATERIJAL I METODE: U istraživanje je uključeno 60 ispitanika sa hiperalimentacionim tipom gojaznosti bez pridruženih komorbiditeta i 30 zdravih normalno uhranjenih učesnika usklađenih sa ispitanicima po godinama života i polu koji su činili kontrolnu grupu. Svim ispitanicima su urađena antropometrijska merenja, analiza komponenata telesne kompozicije (bioelektrična impedansna analiza, Tanita Body Composition Analyzer BC – 418 MA III), laboratorijska analiza uzoraka krvi na automatizovanim analizatorskim sistemima sa određivanjem parametara metabolizma glukoze (bazalno i 2 h u toku oralnog glukoza tolerans testa), lipida i lipoproteina, inflamacije i homocisteina. Određivanje serumske koncentracije sICAM–1 i sE–selektina je vršeno ELISA tehnikom (R&D Systems, Inc. Minneapolis, USA). Vrednosti IMK–a su određivane pomoću karotidnog dupleks ultrazvuka (Aloka SSD–650 US system, Tokyo), a na osnovu izmerenih (IMK) i normalno očekivanih vrednosti IMK za svakog ispitanika je izračunavan IMK Z–skor. Supklinički stadijum ateroskleroze je definisan kao vrednost IMK Z–skora veća od 1 (što odgovara vrednosti IMK većoj od 95 percentila normalno očekivane vrednosti u odnosu na pol i godine života ispitanika). REZULTATI: Ispitanici sa hiperalimentacionim tipom gojaznosti su imali statistički značajno više vrednosti medijane serumske koncentracije sE–selektina u poređenju sa medijanom serumske koncetracije sE–selektina učesnika u kontrolnoj grupi (36,2 (33,21–43.7) vs. 25,14 (23,1–29,48) ng/mL, P=0,00). Gojazni ispitanici III stepena gojaznosti su imali statistički značajno višu medijanu serumske koncenracije sE–selektina u odnosu na medijanu sE–selektina u ispitanika I stepena gojaznosti (41,5 (36,58–49,48) vs. 34,34 (22,49–36,62) ng/mL, P=0,00), odnosno medijanu sE–selektina u ispitanika II stepena gojaznosti (41,5 (36,58–49,48) vs. 32,1 (26,1–43,64) ng/mL, P=0,00). Nije uočena statistički značajna razlika u medijani serumske koncentracije sE–selektina između ispitanika I i II stepena gojaznosti (34,34 (22,49–36,62) vs. 32,1 (26,1–43,64) ng/mL, P=0,12). Gojazni ispitanici su imali statistički značajno više vrednosti medijane serumske koncentracije sICAM–1 u poređenju sa medijanom serumske koncetracije sICAM–1 učesnika u kontrolnoj grupi (266,8 (245,8–326,73) vs.183,32 (167,9–208,57), P=0,00). U ispitivanoj grupi gojaznih uočena je statistički značajna razlika u medijani koncentracije sICAM–1 između ispitanika u I, II i III stepena gojaznosti (200,6 (190,26 - 264,4) vs. 278,5 (219,54 - 343,24) vs. 329,6 (259,2 - 350,34) ng/mL, P=0,00). Učestalost IMK Z–skor > 1 je bila statistički značajno eća u gojaznih ispitanika u odnosu na kontrolnu grupu (36/60 vs. 7/30, P=0,00). Ispitanici sa IMK Z–skor > 1 su imali statistički značajno višu medijanu koncentracije sICAM–1 u odnosu na ispitanike kod kojih je IMK Z–skor ≤ 1 (295,4 (238,46–340,38) vs. 244,2 (227,35–260,38), P=0.00). Regresionom analizom (R2=0,71, korigovani R2=0,59) je utvrđeno da su parametri hsCRP (β=0,45, P=0,00), HOMA–IR (β=0,44, P=0,035) i ISI (β=–0,36, P=0,028) nezavisno i statistički značajno povezani sa serumskom koncentracijom sE–selektina. Regresionom analizom (R2=0,65, korigovani R2=0,56) je utvrđeno da parametri ITM (β=0,55, P=0,00), trigliceridi (β=0,30, P=0,00), HDL holesterol (β=–0,31, P=0,00), odnos TG/HDL–holesterol (β=0,33, P=0,01), hsCRP (β=0,31, P=0,00) i fibrinogen (β=0,34, P=0,00) su nezavisno i statistički značajno povezani sa serumskom koncentracijom sICAM–1. U faktorskoj analizi je izdvojeno pet faktora “gojaznost”, “insulinska rezistencija”, “aterogeni faktor”, “endotelna disfunkcija i vaskularna inflamacija” i “metabolički faktor” koji objašnjavaju 69.72% ukupne varijanse ispitivanog uzorka. U multivarijabilnom modelu sa svim faktorima zajedno kojim je objašnjeno ukupno 75% varijanse, jedino je faktor gojaznost imao statički značajan i nezavistan uticaj na vrednost IMK Z–skor > 1 (OR=2,74 (CI 1,18–6,33), P=0,019). U faktoru gojaznost su se izdvojili parametri: FAT trunk (%), FAT (%), OS (cm), ITM (kg/m2), LDL – holesterol (mmol/L), SP (mmHg), HOMA1–%B, fibrinogen (g/L), ApoB/apoA-I i hsCRP (mg/L). Univarijantom logističkom regresijom je uočeno da porast u koncentraciji LDL–H (OR=5,33 (CI 1,9–14,2), P=0,02) i koncentraciji hsCRP–a (OR=2,53 (CI 1,3–3,98),P=0,017) povećava rizik za postojanje vrednosti IMK Z–skor > 1. ZAKLJUČAK: Cirkulišuće serumske koncentracije biomarkera disfunkcije vaskularnog endotela, sE–selektina i sICAM–1, su značajno više kod ispitanika sa hiperalimentacionim tipom gojaznosti u odnosu na njihove koncentracije u normalno uhranjenih ispitanika. U gojaznih ispitanika, koncentracija sE–selektina je povezana sa vrednostima indeksa insulinske rezistencije i biomarkera inflamacije, dok je koncentracija sICAM–1 značajno povezana sa udelom masne mase u ukupnoj telesnoj masi, vrednostima biomarkera inflamacije i proaterogenih lipidskih parametara. Ispitanici kod kojih postoji uvećanje abdominalnih masnih depoa i ukupnog udela masnog tkiva u telesnoj masi, vrednosti SKP, koncentracije LDL – holesterola, vrednosti lipoproteinskog indeksa ApoAI/apoB, bazalne insulinemije i biomarkera inflamacije, imaju trostruko povećan rizik od supkliničkog stadijuma ateroskleroze. U gojaznih osoba prilikom procene rizika od aterosklerotskih KVB, potrebno je utvrditi fenotipske osobine vaskularnog endotela i eventualno postojanje supkliničkog stadijuma ateroskleroze, da bi se definisale adekvatne preventivne mere i sagledale potencijalne terapijske mogućnosti.</p> / <p>INTRODUCTION: Obesity is a chronic, multifactorial and complex disease associated with an increased risk of atherosclerotic cardiovascular diseases (CVD). Vascular endothelial dysfunction is an early event in the pathophysiological continuum of atherosclerotic process. The prolonged exposure of vascular endothelium to classical and obesity associated risk factors (insulin resistance, dyslipidemia, proinflammatory state) could further promote deterioration of endothelial function and progression of atherosclerosis to subclinical or clinical form of disease. OBJECTIVE: The aim of the study was to compare the concentration of soluble forms of adhesion molecules, intracellular adhesion molecule-1 (sICAM-1) and E-selectin (sE-selectin), between obese subjects and normal weight healthy subjects, as well as to determine the possible existence of differences in concentration of sICAM-1 and sE-selectin among subjects with subclinical stage of atherosclerosis (assessed by measuring the thickness of the intima media complex of the carotid artery (IMT)), and subjects who have a normal value of IMT. Also, the aim was to determine the association between the parameters of body composition (total body fat mass and fat mass intra-abdominal depots), circulating concentrations of sICAM-1 and sE-selectin, and value of IMT in obese subjects. MATERIALS AND METHODS: The study included 60 obese nondiabetic subjects, without preexisting CVD and other associated comorbidity, and 30 healthy normal weight age and sex matched participants. All subjects underwent anthropometric measurements, analysis of the components of body composition (bioelectrical impedance analysis, Tanita Body Composition Analyzer BC - 418 MA III), laboratory analysis of blood samples (automated analyzer systems) with determining the parameters of glucose metabolism (basal and 2 h during the oral glucose tolerance test), lipids and lipoproteins, inflammation and homocysteine. Serum concentrations of sICAM-1 and sE-selectin were determined by ELISA (R & D Systems, Inc., Minneapolis, USA). The values of IMK were determined by carotid duplex ultrasound (Aloka – ProSound ALPHA 10). IMK Z-score was calculated using the measured and the normal expected values of IMT for each patient. Subclinical stage of atherosclerosis was defined as the value of IMT Z-score greater than 1 (corresponding to the 95th sex-age-specific percentile of IMT measurements). RESULTS: Obese subjects had significantly higher median sE-selectin serum concentrations compared to median serum concentrations of sE-selectin in the normal weight subjects (36.2 (33.21-43.7) vs 25.14 (23.1-29.48) ng/mL, P=0.00). Morbid obesity subjects had significantly higher sE-selectin median serum concentration compared to the median sE-selectin concentration in moderate obese subjects (41.5 (36.58-49.48) vs 34.34 (22.49-36.62) ng/mL, P=0.00), and compared to the median sE-selectin concentration in severely obese subjects (41.5 (36.58-49.48) vs. 32.1 (26.1-4364) ng / mL, P=0.00). Obese subjects had significantly higher median sICAM-1 serum concentration compared to median sICAM-1 serum concentration in the control group (266.8 (245.8-326.73) vs. 183.32 (167.9-208.57), P=0.00). In the obese group, we observed a statistically significant difference in median sICAM-1 serum concentrations between moderate, severely and morbid obese subjects (200.6 (190.26-264.4) vs. 278.5 (219.54-343.24) vs. 329.6 (259.2-350.34) ng/mL, P=0.00). The frequency of IMT Z-score> 1 was significantly higher in the obese group compared to control group (36/60 vs. 7/30, P=0.00). Subjects with IMT Z-score> 1 had significantly higher median concentrations of sICAM-1 compared to those in which the IMK Z-score ≤ 1 (295.4 (238.46-340.38) vs. 244.2 ( 227.35-260.38), P=0.00). In regression analysis (R2=0.71, adjusted R2=0.59), hsCRP (β=0.45, P=0.00), HOMA-IR (β=0.44, P=0.035) and ISI (β=-0.36, P=0.028) were independently and significantly associated with serum sE-selectin concentration. In regression analysis (R2=0.65, adjusted R2=0.56), BMI (β=0.55, P=0.00), triglycerides (β=0.30, P=0.00), HDL cholesterol (β=-0.31, P=0.00), the ratio of TG/HDL-cholesterol ratio (β=0.33, P=0.01), hsCRP (β=0.31, P=0.00 ) and fibrinogen (β=0.34, P=0.00) were independently and significantly associated with serum sICAM-1 concentration. In the Factor analysis, five factors "obesity", "insulin resistance", "atherogenic factor," "endothelial dysfunction and vascular inflammation" and "metabolic factor" explained 69.72% of the total variance of the test sample. In a multivariate model with all the factors together (75% of the total variance), "obesity" factor was significantly and independently associated with IMT Z-score> 1 (OR=2.74 (CI 1.18-6.33), P=0.019). The "obesity" factor consisted of parameters: trunk fat (%), fat (%), waist (cm), BMI (kg/m2), LDL – cholesterol (mmol/L), systolic blood presure (mmHg), HOMA1-% B, fibrinogen (g/L), Apo B/apoA-I and hsCRP (mg/L). Logistic regression analysis showed that independent predictors of IMT Z-score> 1 were LDL-cholesterol (OR=5.33(CI 1.9-14.2), P=0.02) and hsCRP (OR=2.53 (CI 1.3-3.98), P=0.017). CONCLUSION: Circulating serum concentrations of endothelial dysfunction biomarkers, sE-selectin and sICAM-1, were significantly higher in obese subjects compared to concentration in the normal weight subjects. In obese subjects, the concentration of sE-selectin was associated with insulin resistance and biomarkers of inflammation, whereas sICAM-1 concentration was associated with fat mass, inflammation biomarkers and the proatherogenic lipid parametars. In individuals with increased abdominal fat depots and total proportion of fat mass in the body weight, values of SBP, LDL-C, ApoB/apoA-I, basal insulin levels and biomarkers of inflammation, there is threefold increased risk of subclinical stages of atherosclerosis. In order to define an adequate preventive measures and possible therapeutic options for atherosclerotic CVD in obese subjects, it is necessary to assess the phenotypic characteristics of vascular endothelium and possible presence of subclinical stage of atherosclerosis.</p>
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MICROPIPETTE CELL ADHESION ASSAY: A NOVEL <i>IN VITRO</i>ASSAY TO MODEL LEUKOCYTE ADHESION IN THE PULMONARY CAPILLARIES OF THE LUNGSundd, Prithu January 2007 (has links)
No description available.
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Investigation of Interactions Between Galectin-3 and P-selectin via Ligands on Breast Cancer Cell LinesHall, Sarah Jane 16 September 2022 (has links)
No description available.
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DIFFERENTIAL GENE EXPRESSION DURING ISCHEMIA AND REPERFUSION IN AN EXTRACORPOREAL SMALL BOWEL PERFUSION MODEL IN SWINE / Differentielle Genexpression während Ischämie und Reperfusion im Modell der extrakorporalen Dünndarmperfusion am SchweinHosseini, Seyed Mehdi 30 October 2002 (has links)
No description available.
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Ispitivanje endotelne disfunkcije i postojanja rezistencije na antitrombocitnu terapiju kod bolesnika sa tipom 2 dijabetes melitusa / Endothelial dysfunction and antiplatelet therapy resistance assessment in patients with type 2 diabetes mellitusMijović Romana 26 September 2016 (has links)
<p>UVOD: Procesi koji obuhvataju endotelnu disfunkciju, oksidativni stres, hroničnu inflamaciju, hiperaktivnost i aktivaciju trombocita te narušavanje ravnoteže procesa koagulacije i fibrinolize od najranijih faza razvoja dijabetes melitusa tip 2 (T2DM) promovišu aterogenezu i nastanak aterotromboznih komplikacija. Kompleksan terapijski pristup u T2DM ima za cilj ne samo uspostavljanje glikoregulacije, korekciju brojnih metaboličkih poremećaja i modifikaciju pridruženih faktora rizika za nastanak ateroskleroze već i primenu antitrombocitne terapije u cilju primarne ili sekundarne prevencije aterotromboznih komplikacija. Uprkos primenjenoj antiagregacionoj terapiji, deo bolesnika doživi rekurentne aterotrombozne atake. Bolesnici sa T2DM se izdvajaju kao grupa sa posebnim rizikom za recidivantne aterotromboze što može biti uslovljeno rezistencijom na primenjenu antitrombocitnu terapiju. Praćenje efekata antitrombocitne terapije i blagovremeno identifikovanje rezistentnih bolesnika ima za cilj optimizaciju primenjene antitrombocitne terapije što može biti od izuzetnog kliničkog značaja u smislu sprečavanja progresije aterotromboznog procesa. CILJ: Proceniti i uporediti nivoe biomarkera, pokazatelja endotelne aktivacije, aktivacije i agregabilnosti trombocita u bolesnika sa bolešću arterijskih krvnih sudova u tipu 2 dijabetes melitusa u odnosu na njihove vrednosti u zdravoj populaciji. Uporediti efikasnost primenjene antitrombocitne terapije tienopiridinima u bolesnika sa tipom 2 dijabetes melitusa i bolešću arterijskih krvnih sudova u odnosu na efikasnost ove terapije u nedijabetičnoj populaciji bolesnika sa bolešću arterijskih krvnih sudova. MATERIJAL I METODE: U ispitivanje je uključeno 100 ispitanika oba pola, starosti od 33 do 70 godina života, kod kojih je prethodno utvrđeno postojanje neke od kliničkih manifestacija bolesti arterijskih krvnih sudova (IBS, CVB, PAB) koji kao antitrombocitnu terapiju uzimaju tienopiridinski preparat, klopidogrel. Od toga, 50 uključenih ispitanika imalo je dijagnozu dijabetes melitus tipa 2, a 50 su bili bolesnici bez dijabetesa. Kontrolnu grupu je činilo 30 klinički i biohemijski zdravih ispitanika, nepušača koji su prema polnoj i dobnoj strukturi odgovarali ispitivanim grupama bolesnika. Svim ispitanicima su urađena antropometrijska merenja, laboratorijska analiza uzoraka krvi na automatizovanim analizatorima sa određivanjem parametara metabolizma glukoze, lipida, parametera inflamacije, KKS, parmetara koagulacije i trombocitnih pokazatelja. Određivanje serumske koncentracije sE–selektina i sP-selektina je vršeno ELISA tehnikom (R&D Systems, Inc. Minneapolis, USA). Plazmatska koncentracija vWFAg-a određivana je imunoturbidimetrijskom metodom na koagulacionom analizatoru Siemens Healthcare Diagnostics, Nemačka. Agregabilnost trombocita je određivana impedantnom agregometrijom (Multiple Electrode Aggregometry - MEA) na Multiplate analizatoru, Dynabyte, Minhen, Nemačka. Bazalna agregabilnost trombocita procenjivana je TRAP testom, rezidualna agregabilnost trombocita pod terapijom klopidogrela ADP testom, rezidualna agregabilnost trombocita pod terapijom aspirina, ASPI testom. Individualni odgovor na primenjenu antiagregacionu terapiju je procenjivan i na osnovu procenta sniženja bazalne agregabilnosti trombocita (%SAT) nakon primenjene antiagregacione terapije što je izračunato sledećim formulama: procena antiagregacionog efekta klopidogrela:%SATadp =100 x (1-ADP/TRAP) i procena antiagregacionog efekta aspirina:%SATaspi =100 x (1-ASPI/TRAP). REZULTATI: Nivo sE-slektina je bio signifikantno viši u bolesnika sa T2DM u odnosu na bolesnike bez dijabetesa (45,1±18,1vs.31,8±10,5ng/ml; p<0,001) i kontrolnu grupu zdravih ispitanika (45,1±18,1vs.27,2±11,2ng/ml; p<0,001). Plazmatski nivo vWF Ag, bio je statistički značajno viši u bolesnika sa T2DM u odnosu na grupu ispitanika bez dijabetesa (172±75,2vs. 146±40,6%; p=0,045), kao i u odnosu na kontrolnu grupu zdravih (172±75,2vs.130±33,8%; p=0,007). Nivo sPselektina bio je statistički značajno viši kod bolesnika s T2DM u odnosu na ispitanike u grupi dijabetesa (95,2±31,8vs.84,0±21,8 ng/ml; p=0,042) i kontrolnoj grupi (95,2±31,8vs.76,7±16,2ng/ml; p=0,004). Uočeno je da je %rP statistički bio značajno viši u grupi dijabetičara u odnosu na grupu ispitanika bez dijabetesa (3,47±1,30vs.2,30±1,30%; p<0,001) i kontrolnu grupu zdravih (3,47±1,30vs.2,29±1,23%; p<0,001). Bolesnici sa T2DM imali su statistički značajno više vrednosti ADP testa (70,3±22,0vs.56,9±19,7U; p=0,002) u odnosu na bolesnike bez dijabetesa, a uočen je i značajno niži stepen procenta sniženja bazalne agregabilnosti, %SATadp, u dijabetičara u odnosu na ispitanike bez dijabetesa (31,6±12,4vs. 48,6±12,6 %; p<0,001). U grupi ispitanika sa T2DM vrednost TRAP testa statistički značajno pozitivno koreliše sa brojem neutrofila (r=0,349;p= 0,013) i NLR-om (r=0,472;p=0,001), a multivarijantnom linearnom regresionom analizom dokazana je nezavisna povezanost TRAP testa i fibrinogena (B=9,61;p=0,009). Takođe, u istoj ispitivanoj grupi postoji pozitivna povezanost ADP testa sa HOMAIR (r=0,319;p=0,024), NLR-om (r=0,515;p<0,001), hsCRP-om (r=0,356;p=0,011), kao i sa %rP (r=0,302;p=0,049). Multivarijantnom linearnom regresionom analizom dokazana je nezavisna povezanost ADP testa i ITM (B=1,43;p=0,043). %SATadp u bolesnika sa T2DM negativno je korelisao sa ITM (r= -0,381;p=0,006), OS (r= - 0,387;p=0,006), HOMA-IR (r= -0,349;p=0,013), hsCRP-om (r= -0,288; p=0,043), %rP (r= -0,302;p=0,049), sE-selektinom (r= -0,369; p=0,008) i sP-selektinom (r= - 0,374;p=0,007). U grupi dijabetičara, postoji pozitivna povezanost %rP sa ITM (r=0,365;p= 0,016), OS (r=0,435;p=0,004), HOMA-IR (r=0,409;p=0,006), hsCRP (r=0,374;p=0,014), sP-selektinom (r=0,341;p=0,025) i vWFAg-om (r=0,348;p=0,022). Takođe, sE-selektin pozitivno koreliše sa ITM (r=0,380;p =0,006), OS (r=0,380; p=0,007), HOMA-IR (r=0,339;p=0,016), hsCRP-om (r=0,351;p=0,013), a sP-selektin sa ITM (r=0,312;p=0,027), OS (r=0,395;p=0,005), HOMA-IR (r=0,286;p=0,044), hsCRP-om (r=0,369; p=0,008) i nivoom sE – selektina (r=0,560;p <0,001). Evaluirajući odgovor na terapiju klopidogrelom u podgrupama bolesnika sa dijabetesom, napravljenim prema kvartilnoj distribuciji nivoa ADP-a, tj. stepenu rezidualne agregabilnosti trombocita u toku terapije klopidogrelom, uočeno je da ukupna bazalna agregabilnost trombocita procenjena TRAP testom statistički značajno raste od prvog do četvrtog kvartila (76,50 ±19,91 vs. 94,54±16,67 vs. 112,00±10,22 vs. 128,92±15,69U;p<0,001), dok se %SATadp od prvog do četvrtog kvartila značajno smanjivao (40,44±13,33 vs. 31,20±11,82 vs. 33,16±7,03 vs. 21,53±10,16%). ZAKLJUČAK: Koncentracije cirkulišućih biomarkera endotelne aktivacije, sE – selektina i vWF Ag-a, solubilnog biomarkera trombocitne aktivacije, sP – selektina, kao i procenat retikulisanih trombocita, %rP, markera trombocitnog prometa, značajno su povišene kod bolesnika sa bolešću arterijskih krvnih sudova u tipu 2 dijabetes melitusa u odnosu na njihove koncentracije kod zdravih ispitanika i bolesnika bez dijabetesa. Bolesnici sa T2DM imali su znatno viši stepen rezistencije na antitrombocitnu terapiju klopidogrelom u odnosu na bolesnike bez dijabetesa, procenjene stepenom rezidualne agregabilnosti trombocita, ADP test, kao i procentom sniženja ukupne bazalne agregabilnosti trombocita, %SATadp, metodom impedantne agregometrije, a što je uslovilo i trend učestalijeg ponavljanja ishemijskih ataka u odnosu na bolesnike bez dijabetesa. Međusobna povezanost ispitivanih biomarkera endotelne i trombocitne aktivacije (sE – selektina, vWF Aga, sP – selektina), kao i markera prometa trombocita (%rP) sa metaboličko inflamatornim parametrima i sa indikatorima odgovora na antiagregacionu terapiju, može ukazivati na to da nepovoljan metabolički milje dijabetičara može biti jedan od doprinosnih faktora lošem odgovoru na antitrombocitnu terapiju klopidogrelom.</p> / <p>INTRODUCTION: Processes involving endothelial dysfunction, oxidative stress, chronic inflammation, platelet activation and the imbalance between coagulation and fibrinolysis promote atherogenesis and atherothrombotic complications at early stage of diabetes mellitus type 2 (T2DM). The complex therapeutic approach in T2DM aims not only to reestablish glycemic control and to correct a number of metabolic disorders, but also to achieve primary or secondary prevention of atherothrombotic complications. Despite the applied antiplatelet therapy, some patients experience recurrent atherothrombotic attacks. Patients with T2DM are the group at particular risk for recurrent atherothrombosis, which can be caused by antiplatelet therapy resistance. Monitoring the effectiveness of antiplatelet therapy and identification of resistant patients aims to optimize the applied antiplatelet therapy, which can be of great clinical significance in terms of preventing progression of atherotrombotic processes. AIM: Evaluate and compare the levels of biomarkers, indicators of endothelial activation, platelet activation and aggregability in patients with arterial vascular disease in type 2 diabetes mellitus compared to their values in a healthy population. Compare the effectiveness of applied antiplatelet therapy with thienopyridines in patients with type 2 diabetes mellitus and arterial vascular disease compared to the efficacy of this therapy in nondiabetic population of patients with arterial vascular disease. MATERIAL AND METHODS: The study included 100 patients, 33 to 70 years of age, with previously established existence of some of the clinical manifestations of arterial vascular disease (CAD, CVD, PAD), taking thienopyridine antiplatelet therapy with clopidogrel. 50 patients was previously diagnosed with diabetes mellitus type 2 and 50 were nondiabetic patients. Control group included 30 age and sex matched healthy participants, non-smokers. All subjects underwent anthropometric measurements and laboratory analysis of blood samples on automated analyzers with determining the parameters of glucose metabolism, lipids, inflammation parameters, complete blood count, coagulation and platelet parameters. Serum concentrations of sEselectin and sP-selectin were determined by ELISA (R&D Systems, Inc., Minneapolis, USA). vWFAg was determined by immunoturbidimetry on coagulometer Siemens Healthcare Diagnostics, Germany. Platelet aggregability was determined by impedance aggregometry (Multiple Electrode Aggregometry - MEA) on Multiplate analyzer, Dynabyte, Munich, Germany. Basal platelet aggregability was estimated by TRAP test, residual platelet aggregability during clopidogrel treatment was estimated by ADP test and during aspirin treatement by ASPI test. Individual response to antiplatelet therapy was estimated by the percentage of decrease in basal platelet aggregability (%DPA) obtained after antiplatelet therapy, calculated bypresented formulas: %DPAadp =100 x (1-ADP/TRAP)and %DPAaspi =100 x (1- ASPI/TRAP). RESULTS: Concentration of sE-selectin was significantly higher in patients with T2DM in order to non-diabetic patients (45,1±18,1vs.31,8±10,5ng/ml;p<0,001) and healthy control group (45,1±18,1vs.27,2±11,2ng/ml; p<0,001). vWF Ag was significantly higher in diabetic patients than in non-diabetics (172±75,2vs. 146±40,6%; p=0,045) and healthy controls (172±75,2vs.130±33,8%; p=0,007). sP-selectin was also significantly higher in patients with T2DM than in non-diabetics (95,2±31,8vs.84,0±21,8 ng/ml; p=0,042) and healthy controls (95,2±31,8vs.76,7±16,2ng/ml; p=0,004). %rP was significantly higher in group of patients with T2DM than in nondiabetic patients (3,47±1,30vs.2,30±1,30%; p<0,001) and healthy control group (3,47±1,30vs.2,29±1,23%; p<0,001). T2DM patients had statistically higher values of ADP test (70,3±22,0vs.56,9±19,7U; p=0,002) compared to patients without diabetes, and significantly lower %DPAadp (31,6±12,4vs. 48,6±12,6 %; p<0,001). In T2DM group of patients, level of TRAP test correlated positively with number of white blood cells (r=0,349;p= 0,013) and NLR (r=0,472;p=0,001), and multivariant linear regression analisys showed significant independent association of TRAP test with fibrinogen (B=9,61;p=0,009). Statistically significant positive correlation of ADP test with HOMA-IR (r=0,319;p=0,024), NLR (r=0,515;p<0,001), hsCRP (r=0,356;p=0,011) and %rP (r=0,302;p=0,049) was observed in patients with T2DM. Multivariant linear regression analisys showed significant independent association of ADP test with BMI (B=1,43;p=0,043). %DPAadp negatively correlated with BMI (r=-0,381;p=0,006), WC (r= - 0,387;p=0,006), HOMA-IR (r= -0,349;p=0,013), hsCRP (r= -0,288; p=0,043), %rP (r= -0,302;p=0,049), sE-selectin (r= -0,369; p=0,008) and sP-selectin (r= -0,374;p=0,007) in diabetic patients. Significant positive correlation of %rP with BMI (r=0,365;p= 0,016), WC (r=0,435;p=0,004), HOMA-IR (r=0,409;p=0,006), hsCRP (r=0,374;p=0,014), sP-selectin (r=0,341;p=0,025) and vWFAg (r=0,348;p=0,022) was found in diabetics. Also, sE-selectin positively correlated with BMI (r=0,380;p =0,006), WC (r=0,380; p=0,007), HOMA-IR (r=0,339;p=0,016), hsCRP(r=0,351;p=0,013), and sPselectin correlated positively with BMI (r=0,312;p=0,027), WC (r=0,395;p=0,005), HOMA-IR (r=0,286;p=0,044), hsCRP (r=0,369; p=0,008) and sE – selectin (r=0,560;p <0,001). Evaluating the response to clopidogrel therapy in subgrpoups of diabetic patients accoarding the quartile distribution of ADP test (clopidogrel on-treatment platelet reactivity), it is found that total basal aggregability estimated by TRAP test significantly increased from the first to the fourth quartile (76,50 ±19,91 vs. 94,54±16,67 vs. 112,00±10,22 vs. 128,92±15,69U;p<0,001) while %DPAadp decreased (40,44±13,33 vs. 31,20±11,82 vs. 33,16±7,03 vs. 21,53±10,16%). CONCLUSION: Concentration of circulating biomarkers of endothelial activation, sE-selectin and vWF Ag, soluble marker of platelet activation, sP – selectin, as well as percentage of reticulated platelets, %rP, marker of platelet turnover, were significantly higher in patients with arterial vascular disease in T2DM compared to healthy controls and non-diabetics. Patients with T2DM had significantly higher degree of resistance to antiplatelet therapy with clopidogrel compared to non diabetics, estimated by ADP test, as well as with %DPAadp, what caused more frequent recurrent ischemic attacks compared to nondiabetic patients. Correlation of biomarkers of endothelial and platelet activation (sE – selectin, vWF Ag, sP – selectin) and markers of platelet turnover (%rP) with metabolic profile indicators and poor antiplatelet therapy response suggest that altered metabolic profile can be one of contributing factors of poor antiplatelet response in diabetic patients.</p>
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Synthèse d'une librairie d'analogues monomériques et dimériques du sLe XCalosso, Mickael 09 1900 (has links)
Dans cet ouvrage sera décrite la synthèse de nouveaux analogues du sialyl
Lewis X (sLex). A cet effet, nous avons préparé une librairie d’analogues synthétisée
à partir d’une approche mettant en jeu un «espaceur» acyclique permettant d’avoir un
biais conformationnel que nous avons défini comme la stratégie ATC-B.
Nous avions déjà démontré que certains analogues portant un groupe benzoate
en C-2 et en C-4 du galactose présentent une activité 50 fois supérieure à celle du
sLex. Nous avions par ailleurs démontré qu’en l’absence du benzoate en C-2,
l’activité devient alors trois fois plus faible. A présent, il paraissait interessant de
synthétiser des analogues ayant seulement un groupe benzoate en C-4 pour evaluer
l’impact de ce groupement sur la puissance de nos analogues.
Par le passé, nous avions également mis en évidence le rôle des esters sur
l’activité des analogues portant un «espaceur» acyclique dans le cadre de la stratégie
ATC-B. Nous effectuerons donc des variations à ce niveau pour en évaluer l’impact.
Enfin, nous avons préparé une nouvelle famille d’analogues de type dimère.
Ceux-ci seront constitués de 2 unités des composés monomériques synthétisés
précédemment. La synthèse de ces dimères fera l’emploi de la «Click Chemistry».
Cette étude nous mènera a vous présenter la synthèse de ces composés et la
méthodologie employée. / This work describes the synthesis of novel sialyl Lewis X (sLex) analogues.
To this end, we have prepared a library of analogues by implementing a strategy that
makes use of an Acyclic Tether which allows for defined Conformational Bias (ATCB
strategy).
We have previously shown that analogues bearing a benzoate group at both
positions C-2 and C-4 of the galactose exert an activity 50-fold greater than that of
sLex. Indeed, removing the benzoate at position C-4 while keeping the one at C-2 led
to a three fold decrease in potency. We are currently preparing the corresponding
analogues that have the benzoate only at position C-4 in order to fully evaluate its
impact on the potency of the analogue.
We have also previously elucidated the role of esters on the activity of
analogues that have acyclic tether as part of the ATC-B strategy. Variations have
been made at the level of the ester and their impact has been evaluated.
Lastly, we have prepared a novel family of analogues consisting of two
identical monomeric subunits linked together. Synthesis of these dimers was
performed via «Click Chemistry». This study describes the synthesis of the
compounds and the methodology employed.
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Synthèse et formulation des nanoparticules polymère ciblant l'E-sélectine : évaluation in vitro dans un modèle d'endothélium activé / Synthesis and formulation of polymeric nanoparticles targeting E-selectin : in vitro evaluation in a model of activated endotheliumJubeli, Emile 17 May 2011 (has links)
Ce travail de thèse avait pour objectif d’élaborer un système vecteur ciblantl’endothélium pathologiquement activé dans les tissus enflammés, infectés ou tumoraux.Ce vecteur est sous forme de nanoparticules décorées de ligands glycosides capablesd’interagir avec l’E-sélectine, un récepteur exprimé sur les cellules endothélialesactivées.Nous avons mis au point une synthèse de copolymère amphiphile avec une architectureà bloc muni sur sa partie hydrophile d’un ligand glucidique. Ce copolymère a été par lasuite utilisé pour la préparation de nanoparticules de type coeur/couronne. La partiehydrophobe centrale est entourée d’une couronne hydrophile dont l'encombrementstérique et la mobilité limitent l'opsonisation de la particule. Le ciblage actif a été assurépar la présence d’un ligand du récepteur de l’E-sélectine aux extrémités des chaînes depolymères hydrophiles à la surface du vecteur.Avec ces nanoparticules dont les propriétés de surface sont prédéfinies, nous avonsmontré in vitro l’association efficace avec les cellules endothéliales activées, ce qui apermis de valider ce concept de ciblage moléculaire actif par l’intermédiaire du couplerécepteur/ ligand. Un tel système permettra d’améliorer l’indice thérapeutique et labiodistribution des principes actifs anti-inflammatoire et/ou anticancéreux. / The objective of this work was to develop a delivery system targeting pathologically activated endothelium within inflamed, infectious, and some tumoral tissues. This system is composed of nanoparticles bearing sugar residues that are able to recognize and interact with E-selectin, a receptor expressed on the activated endothelial cells.We synthesized an amphiphilic block copolymer with the hydrophilic part terminated by a carbohydrate ligand. The construction was achieved by a combination of click chemisty, ring-opening polymerization and atom transfer radical polymerization. This copolymer was used to prepare nanoparticles of the core/shell type where the central hydrophobic body is surrounded with the hydrophilic shell that can stabilize the particles in aqueous media and limit their opsonisation. Active targeting was achieved by coupling an analogue of sialyl Lewis X, the physiological ligand of E-selectin to the end of the hydrophilic polymer chains on the surface of the particles.We were able to demonstrate in vitro the efficient association of these nanoparticles with defined surface properties with activated endothelial cells. This allowed us to validate our concept of active molecular targeting using this couple receptor/ligand couple. Such a system could be used to improve the therapeutically index and the biodistribution of anti-inflammatory and anti-tumor drugs.
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Effekte von Hyperoxie und Stickstoffmonoxid beim NeugeborenenHöhn, Thomas 01 October 2002 (has links)
In der vorliegenden Arbeit sind Untersuchungen vorgestellt, die sich mit Wirkungen und Interaktionen von zwei ubiquitär im menschlichen Körper vorkommenden Gasen befassen, i.e. Sauerstoff und Stickstoffmonoxid. Im Falle beider Substanzen ermöglicht die geringe Größe der Moleküle eine freie Diffusion über Membranen hinweg, eine Eigenschaft, die für die Funktion der Signaltransduktion geradezu prädestiniert. Aus den vorgelegten Untersuchungen lassen sich die folgenden Folgerungen ableiten: * Stickstoffmonoxid wirkt in-vitro selektiv bakteriostatisch auf Bakterien, die üblicherweise Früh- und Neugeborene besiedeln. Dabei hängt die Selektivität von den jeweiligen bakteriellen Verteidigungsmechanismen ab, die bakteriostatische Wirkung liegt in einem Konzentrationsbereich, der außerhalb desjenigen liegt, der derzeit klinisch angewendet wird. * Hyperoxie führt im Ganztiermodell der unreifen Ratte zu einer zerebralen Hochregulation von iNOS und damit zur Synthese von NO. Soweit dies anhand der Synthese von Peroxynitrit als definitivem Schädigungsmechanismus beurteilbar ist, wird trotz entsprechender iNOS-Expression wenig bis gar kein Peroxynitrit gebildet. Da das Zusammentreffen von NO und Sauerstoff sonst regelhaft zur Entstehung von Peroxynitrit führt, müssen im Gehirn der unreifen Ratte ausreichende antioxidative Schutzmechanismen präsent sein, die diese Reaktion verhindern. * Im in-vitro-Modell der Gasäquilibrierung von Nabelschnur-PMN zeigte sich unter Hyperoxie das ausgeprägteste Aktivierungsmuster aller verglichenen Sauerstoffkonzentrationen. Dies stand im Gegensatz zur Exposition adulter Zellen, hier fand sich eine größere Hyperoxietoleranz bei gleichzeitig stärkster Aktivierung unter Hypoxiebedingungen. Welche Bedeutung diesen Ergebnissen im klinischen Umgang mit Neugeborenen zukommt muß derzeit noch offen bleiben. Allerdings häufen sich Hinweise aus experimentellen Studien, die darauf hindeuten, daß ein restriktiver Umgang mit hohen Sauerstoffkonzentrationen auch im klinischen Umfeld gerechtfertigt sein könnte. / The present investigations deal with the effects and interactions of gases, which are ubiquitous in the human body i.e. oxygen and nitric oxide. Both substances are small enough to freely diffuse across biological membranes. This ability predestines both molecules for the function of signal transduction. The results of our investigations lead to conclusions as follows: * Nitric oxide has selective bacteriostatic effects in-vitro on some bacterial strains typically isolated from preterm and term newborn infants. Selectivity depends on the presence of bacterial defense mechanisms. The bacteriostatic effect takes place at concentrations above those currently used in clinical practice. * Hyperoxia leads to upregulation of iNOS and subsequent NO production in an animal model of the immature rat. Despite this upregulation of iNOS synthesis there is no increased production of peroxynitrite which is known to cause cellular and DNA damage. Since the combination of NO and high concentrations of oxygen lead to peroxynitrite formation on a regular basis, effective antioxidant mechanisms appear to prevent peroxynitrite formation in the brain of the immature rat. * The most pronounced activation of cord blood polymorphonuclear cells (PMN) during conditions of hyperoxia, normoxia, and hypoxia was found for exposure towards high oxygen concentrations in an in-vitro model of gas equilibration. As opposed to that, hypoxia was the most potent trigger for adult PMN. It remains to be determined which clinical implications must be derived from these results. However, increasing experimental evidence indicates that exposure towards high oxygen concentrations should be restricted also in clinical practice and not only in preterm infants, but also in term newborns.
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