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1.
J Environ Manage ; 210: 87-95, 2018 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-29331853

RESUMEN

Studies on the availability of heavy metals in composted organic materials and in soil amended with these materials are of practical significance. They are used in the assessment of the purity of the soil environment and of the biological value of plants intended for human and animal consumption. Composting of organic materials has a significant effect on changes in mobile forms of heavy metals. Therefore, the aim of this study was to determine the effect of the addition of biochar and sewage sludge on (i) the contents of water soluble forms of Cu, Cd, Pb, and Zn in composts; and (ii) the contents of mobile forms of these elements in sandy soil after the addition of composts. Addition of sewage sludge and biochar to maize straw did not increase the heavy metal forms extracted with water in total content of heavy metals. The content of Cd and Cu extracted with water in composts produced from maize straw and sewage sludge, and produced from maize straw, sewage sludge and biochar was higher than the one determined in compost produced from maize straw. The content of Pb and Zn extracted with water in compost produced from maize straw, sewage sludge and biochar was lower than in compost produced from maize straw. The addition of sewage sludge and biochar to maize straw had an immobilizing effect on mobile forms of the studied elements compared to compost produced from maize straw and sewage sludge. The addition of composts to soil decreased the contents of mobile forms of Cu, Cd, and Pb extracted with 1 M NH4NO3 compared to the contents in the control soil. However, the content of Zn extracted with NH4NO3 increased in treatments with 0.5% dose of compost produced from maize straw and sewage sludge and 0.5% dose of compost produced from maize straw, sewage sludge and biochar. In none of the analyzed cases, the application of the composts produced did not exceed the acceptable content of studied elements in the soil.


Asunto(s)
Carbón Orgánico , Compostaje , Metales Pesados/química , Animales , Humanos , Aguas del Alcantarillado , Suelo , Contaminantes del Suelo , Zea mays
2.
J Environ Manage ; 222: 1-2, 2018 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-29800858

RESUMEN

The discussion letter we received was carefully reviewed by us, authors. We would like to thank Moussavi et al. for their interest and emphasis on the originality of our studies. Every substantive discussion on study results is valuable, especially when it gives a new perspective on the results obtained. We would like to note that our manuscript lacks some of the results listed by Moussavi et al., not because of our ignorance, but because of the concept of our manuscript's structure. We would like to point out that the research methods used in the published manuscript were selected based on available literature. We also want to emphasise the very diversified scientific approach to procedures for determining the availability of trace elements in soil. This approach was also noted and clearly justified in many studies. We believe that the diversity of scientists' approach to the investigated subject is a very important and creative component of science.


Asunto(s)
Compostaje , Metales Pesados , Contaminantes del Suelo , Carbón Orgánico , Aguas del Alcantarillado , Suelo , Zea mays
3.
Folia Morphol (Warsz) ; 72(4): 293-9, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-24402749

RESUMEN

The aim of the study was to investigate the distribution of the circle of Willis variants in Polish population by means of computed tomography angiography (CTA). The results were then analysed and compared with another study that used similar methods but that was carried out on an ethnically distinct population. Patients presenting with intracranial pathology were excluded from the initial study population. In total, 250 CTA belonging to 129 female and 121 male patients were reviewed. A modified classification system of the circle was proposed, which took into consideration the anterior and the posterior aspects of the circle individually. The typical variant of Willis's circle occurred in 16.80% of cases. The anterior and the posterior portions of the circle were normal in 47.20% and 26.80% of the patients respectively. As for the anterior part, lack of the anterior communicating artery was the most frequent abnormality (22.80%). Bilateral absence of posterior communicating arteries was the most common anomaly in the posterior part of the circle (29.20%). This type of anomaly was also the most common, when taking into consideration the entire circle (12.00%). There were statistically significant differences between the age groups and genders when considering the occurrence of an incomplete circle. Overall, a substantial proportion of patients manifested clinically important variants that were incapable of providing collateral circulation. Comparison with other imaging-based and cadaveric studies revealed noticeable differences, that may have resulted from the variable technical features of other studies or other factors such as the ethnical origins of the studied populations.


Asunto(s)
Angiografía Cerebral , Círculo Arterial Cerebral/diagnóstico por imagen , Tomografía Computarizada por Rayos X , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Cadáver , Círculo Arterial Cerebral/anomalías , Femenino , Humanos , Masculino , Persona de Mediana Edad , Polonia , Adulto Joven
4.
Radiat Prot Dosimetry ; 199(15-16): 1824-1828, 2023 Oct 11.
Artículo en Inglés | MEDLINE | ID: mdl-37819323

RESUMEN

Currently, the most used methods of plastic scintillator (PS) manufacturing are cell casting and bulk polymerisation, extrusion, injection molding, whereas digital light processing (DLP) 3D printing technique has been recently introduced. For our research, we measured blue-emitting EJ-200, EJ-208, green-emitting EJ-260, EJ-262 cell cast and two types of blue-emitting DLP-printed PSs. The light output of the samples, with the same dimension of 10 mm × 10 mm × 10 mm, was compared. The light output of the samples, relative to the reference EJ-200 cell-cast scintillator, equals about 40-49 and 70-73% for two types of 3D-printed, and two green-emitting cell-casted PSs, respectively. Performance of the investigated scintillators is sufficient to use them in a plastic scintillation dosemeter operating in high fluence gamma radiation fields.


Asunto(s)
Radiometría , Conteo por Cintilación , Conteo por Cintilación/métodos , Impresión Tridimensional
5.
Spectrochim Acta A Mol Biomol Spectrosc ; 268: 120667, 2022 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-34865975

RESUMEN

Raman spectroscopy and Raman imaging are powerful techniques to monitor biochemical composition around blood vessel. The aim of this study was to understand the role of pro- and antiangiogenic factors in angiogenesis process. Raman imaging and Raman single spectrum measurements allow the diagnosis of cancer biochemical changes in blood vessel based on several biomarkers simultaneously. We have demonstrated that Raman imaging combined with statistical methods are useful to monitoring pro- and antiangiogenic factors responsible for angiogenesis process. In this work Raman markers of proangiogenic and antiangiogenic factors were identified based on their vibrational signatures. Obtained results can help understand how growing tumor create its vascular system.


Asunto(s)
Neoplasias , Espectrometría Raman , Inhibidores de la Angiogénesis/farmacología , Diagnóstico por Imagen , Humanos , Neoplasias/tratamiento farmacológico , Vibración
6.
Sci Rep ; 12(1): 2120, 2022 02 08.
Artículo en Inglés | MEDLINE | ID: mdl-35136078

RESUMEN

Cytochrome c (Cyt c) is a key protein that is needed to maintain life (respiration) and cell death (apoptosis). The dual-function of Cyt c comes from its capability to act as mitochondrial redox carrier that transfers electrons between the membrane-embedded complexes III and IV and to serve as a cytoplasmic apoptosis-triggering agent, activating the caspase cascade. However, the precise roles of Cyt c in mitochondria, cytoplasm and extracellular matrix under normal and pathological conditions are not completely understood. To date, no pathway of Cyt c release that results in caspase activation has been compellingly demonstrated in any invertebrate. The significance of mitochondrial dysfunctionality has not been studied in ductal carcinoma to the best of our knowledge. We used Raman spectroscopy and imaging to monitor changes in the redox state of the mitochondrial cytochromes in ex vivo surgically resected specimens of human breast tissues, and in vitro human breast cells of normal cells (MCF 10A), slightly malignant cells (MCF7) and highly aggressive cells (MDA-MB-231). We showed that Raman imaging provides insight into the biology of human breast ductal cancer. Here we show that proper concentration of monounsaturated fatty acids, saturated fatty acids, cardiolipin and Cyt c is critical in the correct breast ductal functioning and constitutes an important parameter to assess breast epithelial cells integrity and homeostasis. We look inside human breast ducts by Raman imaging answering fundamental questions about location and distribution of various biochemical components inside the lumen, epithelial cells of the duct and the extracellular matrix around the cancer duct during cancer development in situ. Our results show that human breast cancers demonstrate a redox imbalance compared to normal tissue. The reduced cytochrome c is upregulated in all stages of cancers development. The results of the paper shed light on a largely non-investigated issues regarding cytochromes and mitochondrial function in electron transfer chain. We found in histopathologically controlled breast cancer duct that Cyt c, cardiolipin, and palmitic acid are the main components inside the lumen of cancerous duct in situ. The presented results show direct evidence that Cyt c is released to the lumen from the epithelial cells in cancerous duct. In contrast the lumen in normal duct is empty and free of Cyt c. Our results demonstrate how Cyt c is likely to function in cancer development. We anticipate our results to be a starting point for more sophisticated in vitro and in vivo animal models. For example, the correlation between concentration of Cyt c and cancer grade could be tested in various types of cancer. Furthermore, Cyt c is a target of anti-cancer drug development and a well-defined and quantitative Raman based assay for oxidative phosphorylation and apoptosis will be relevant for such developments.


Asunto(s)
Neoplasias de la Mama/metabolismo , Carcinoma Ductal de Mama/metabolismo , Citocromos c/metabolismo , Mitocondrias/metabolismo , Espectrometría Raman , Neoplasias de la Mama/diagnóstico por imagen , Neoplasias de la Mama/etiología , Carcinoma Ductal de Mama/diagnóstico por imagen , Carcinoma Ductal de Mama/etiología , Femenino , Humanos , Técnicas In Vitro , Células MCF-7 , Oxidación-Reducción
7.
Sci Rep ; 12(1): 18561, 2022 11 03.
Artículo en Inglés | MEDLINE | ID: mdl-36329066

RESUMEN

Raman spectroscopy and Raman imaging were used to identify the biochemical and structural features of human cancer lung cells (CCL-185) and the cancer cells supplemented with glucose and deuterated glucose at normal and hyperglycemia conditions. We found that isotope substitution of glucose by deuterated glucose allows to separate de novo lipid synthesis from exogenous uptake of lipids obtained from the diet. We demonstrated that glucose is largely utilized for de novo lipid synthesis. Our results provide a direct evidence that high level of glucose decreases the metabolism via oxidative phosphorylation in mitochondria in cancer cells and shifts the metabolism to glycolysis via Warburg effect. It suggests that hyperglycemia is a factor that may contribute to a more malignant phenotype of cancer cells by inhibition of oxidative phosphorylation and apoptosis.


Asunto(s)
Carcinoma , Hiperglucemia , Humanos , Espectrometría Raman , Fosforilación Oxidativa , Glucólisis/fisiología , Glucosa/metabolismo , Lípidos , Pulmón/metabolismo
8.
Spectrochim Acta A Mol Biomol Spectrosc ; 262: 120091, 2021 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-34175760

RESUMEN

Spectroscopic methods provide information on the spatial localization of biochemical components based on the analysis of vibrational spectra. Raman spectroscopy and Raman imaging can be used to analyze various types of human brain tumors and breast cancers. The objective of this study is to evaluate the Raman biomarkers to distinguish tumor types by Raman spectroscopy and Raman imaging. We have demonstrated that bands characteristic for carotenoids (1156 cm-1, 1520 cm-1), proteins (1004 cm-1), fatty acids (1444 cm-1, 1655 cm-1) and cytochrome (1585 cm-1) can be used as universal biomarkers to assess aggressiveness of human brain tumors. The sensitivity and specificity obtained from PLS-DA have been over 73%. Only for gliosarcoma WHO IV the specificity is lower and takes equal 50%. The presented results confirm clinical potential of Raman spectroscopy in oncological diagnostics.


Asunto(s)
Neoplasias Encefálicas , Neoplasias de la Mama , Neoplasias Encefálicas/diagnóstico por imagen , Neoplasias de la Mama/diagnóstico por imagen , Diagnóstico por Imagen , Femenino , Humanos , Espectrometría Raman , Vibración
9.
Sci Rep ; 9(1): 166, 2019 01 17.
Artículo en Inglés | MEDLINE | ID: mdl-30655566

RESUMEN

We have shown that Raman microspectroscopy is a powerful method for visualization of glycocalyx offering cellular interrogation without staining, unprecedented spatial and spectral resolution, and biochemical information. We showed for the first time that Raman imaging can be used to distinguish successfully between glycosylated and nonglycosylated proteins in normal and cancer tissue. Thousands of protein, lipid and glycan species exist in cells and tissues and their metabolism is monitored via numerous pathways, networks and methods. The metabolism can change in response to cellular environment alterations, such as development of a disease. Measuring such alterations and understanding the pathways involved are crucial to fully understand cellular metabolism in cancer development. In this paper Raman markers of glycogen, glycosaminoglycan, chondroitin sulfate, heparan sulfate proteoglycan were identified based on their vibrational signatures. High spatial resolution of Raman imaging combined with chemometrics allows separation of individual species from many chemical components present in each cell. We have found that metabolism of proteins, lipids and glycans is markedly deregulated in breast (adenocarcinoma) and brain (medulloblastoma) tumors. We have identified two glycoforms in the normal breast tissue and the malignant brain tissue in contrast to the breast cancer tissue where only one glycoform has been identified.


Asunto(s)
Adenocarcinoma/metabolismo , Encéfalo/metabolismo , Neoplasias de la Mama/metabolismo , Mama/metabolismo , Neoplasias Cerebelosas/metabolismo , Meduloblastoma/metabolismo , Encéfalo/patología , Mama/patología , Femenino , Humanos , Metabolismo de los Lípidos , Polisacáridos/metabolismo , Proteínas/metabolismo , Espectrometría Raman/métodos
10.
Phys Med Biol ; 52(16): 4953-66, 2007 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-17671346

RESUMEN

Nanodosimetric single-event distributions or their mean values may contribute to a better understanding of how radiation induced biological damages are produced. They may also provide means for radiation quality characterization in therapy beams. Experimental nanodosimetry is however technically challenging and Monte Carlo simulations are valuable as a complementary tool for such investigations. The dose-mean lineal energy was determined in a therapeutic p(65)+Be neutron beam and in a (60)Co gamma beam using low-pressure gas detectors and the variance-covariance method. The neutron beam was simulated using the condensed history Monte Carlo codes MCNPX and SHIELD-HIT. The dose-mean lineal energy was calculated using the simulated dose and fluence spectra together with published data from track-structure simulations. A comparison between simulated and measured results revealed some systematic differences and different dependencies on the simulated object size. The results show that both experimental and theoretical approaches are needed for an accurate dosimetry in the nanometer region. In line with previously reported results, the dose-mean lineal energy determined at 10 nm was shown to be related to clinical RBE values in the neutron beam and in a simulated 175 MeV proton beam as well.


Asunto(s)
Modelos Biológicos , Método de Montecarlo , Nanotecnología/métodos , Terapia por Captura de Neutrón/métodos , Radiometría/métodos , Simulación por Computador , Modelos Estadísticos , Dosificación Radioterapéutica , Análisis de Regresión , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
11.
Radiat Prot Dosimetry ; 126(1-4): 652-6, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17504751

RESUMEN

Secondary neutrons produced in high-energy therapeutic ion beams require special attention since they contribute to the dose delivered to patient, both to tumour and to the healthy tissues. Moreover, monitoring of neutron production in the beam line elements and the patient is of importance for radiation protection aspects around ion therapy facility. Monte Carlo simulations of light ion transport in the tissue-like media (water, A-150, PMMA) and materials of interest for shielding devices (graphite, steel and Pb) were performed using the SHIELD-HIT and MCNPX codes. The capability of the codes to reproduce the experimental data on neutron spectra differential both in energy and angle is demonstrated for neutron yield from the thick targets. Both codes show satisfactory agreement with the experimental data. The absorbed dose due to neutrons produced in the water and A-150 phantoms is calculated for proton (200 MeV) and carbon (390 MeV/u) beams. Secondary neutron dose contribution is approximately 0.6% of the total dose delivered to the phantoms by proton beam and at the similar level for both materials. For carbon beam the neutron dose contribution is approximately 1.0 and 1.2% for the water and A-150 phantoms, respectively. The neutron ambient dose equivalent, H(10), was determined for neutrons leaving different shielding materials after irradiation with ions of various energies.


Asunto(s)
Radioterapia de Iones Pesados , Modelos Biológicos , Neutrones , Monitoreo de Radiación/instrumentación , Protección Radiológica/instrumentación , Efectividad Biológica Relativa , Simulación por Computador , Diseño de Equipo , Análisis de Falla de Equipo , Humanos , Ensayo de Materiales , Dosis de Radiación , Protección Radiológica/métodos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
12.
Eur Phys J C Part Fields ; 77(7): 475, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28943795

RESUMEN

The Compact Linear Collider (CLIC) is an option for a future [Formula: see text] collider operating at centre-of-mass energies up to [Formula: see text], providing sensitivity to a wide range of new physics phenomena and precision physics measurements at the energy frontier. This paper is the first comprehensive presentation of the Higgs physics reach of CLIC operating at three energy stages: [Formula: see text], 1.4 and [Formula: see text]. The initial stage of operation allows the study of Higgs boson production in Higgsstrahlung ([Formula: see text]) and [Formula: see text]-fusion ([Formula: see text]), resulting in precise measurements of the production cross sections, the Higgs total decay width [Formula: see text], and model-independent determinations of the Higgs couplings. Operation at [Formula: see text] provides high-statistics samples of Higgs bosons produced through [Formula: see text]-fusion, enabling tight constraints on the Higgs boson couplings. Studies of the rarer processes [Formula: see text] and [Formula: see text] allow measurements of the top Yukawa coupling and the Higgs boson self-coupling. This paper presents detailed studies of the precision achievable with Higgs measurements at CLIC and describes the interpretation of these measurements in a global fit.

13.
Spectrochim Acta A Mol Biomol Spectrosc ; 169: 182-91, 2016 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-27376758

RESUMEN

Raman microspectroscopy combined with fluorescence were used to study the distribution of Hematoporphyrin (Hp) in noncancerous and cancerous breast tissues. The results demonstrate the ability of Raman spectroscopy to distinguish between noncancerous and cancerous human breast tissue and to identify differences in the distribution and photodegradation of Hematoporphyrin, which is a photosensitizer in photodynamic therapy (PDT), photodynamic diagnosis (PDD) and photoimmunotherapy (PIT) of cancer. Presented results show that Hematoporphyrin level in the noncancerous breast tissue is lower compared to the cancerous one. We have proved also that the Raman intensity of lipids and proteins doesn't change dramatically after laser light irradiation, which indicates that the PDT treatment destroys preferably cancer cells, in which the photosensitizer is accumulated. The specific subcellular localization of photosensitizer for breast tissues samples soaked with Hematoporphyrin was not observed.


Asunto(s)
Neoplasias de la Mama/diagnóstico por imagen , Mama/diagnóstico por imagen , Hematoporfirinas/análisis , Imagen Óptica/métodos , Fármacos Fotosensibilizantes/análisis , Espectrometría Raman/métodos , Femenino , Humanos , Espectrometría de Fluorescencia/métodos
14.
Biochim Biophys Acta ; 616(2): 167-78, 1980 Dec 04.
Artículo en Inglés | MEDLINE | ID: mdl-6111338

RESUMEN

Heat denatured type I and type III calf skin collagen were found to be substrates for guinea pig liver transglutaminase (R-glutaminyl-peptide:amine gamma-glutamyl-yltransferase, EC 2.3.2.13) but not for active plasma factor XIII (factor XIIIa). Liver transglutaminase was shown to catalyse incorporation of 14C-putrescine into subunits of denatured collagen of both types, cross-linking of the latter into high molecular weight polymers and their co-cross-linking to fibrin and fibrinogen. Factor XIIIa is inactive in these respects. None of these reactions was catalysed by liver transglutaminase and plasma factor XIIIa when nondenatured collagens both soluble or in the forms of reconstituted fibrils served as substrates. Some cross-linking of cleavage products of collagen type I (obtained by treatment with collagenase from human neutrophiles) was induced by liver transglutaminase and factor XIIIa. The results indicate that although appropriate glutamine and lysine residues for a epsilon-(gamma-glutamine) lysine cross-linked formation are present in collagen, the native conformation of collagen prevents the action of liver transglutaminase and factor XIIIa.


Asunto(s)
Colágeno/metabolismo , Factor XIII/metabolismo , gamma-Glutamiltransferasa/metabolismo , Animales , Bovinos , Fibrina/metabolismo , Cobayas , Técnicas In Vitro , Hígado/enzimología , Conformación Proteica , Desnaturalización Proteica , Piel/metabolismo , Especificidad por Sustrato , Transglutaminasas
16.
Radiat Prot Dosimetry ; 115(1-4): 58-62, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-16381682

RESUMEN

A Monte Carlo study of the Feynman-method with a simple code simulating the multiplication chain, confined to pertinent time-dependent phenomena has been done. The significance of its key parameters (detector efficiency and dead time, k-source and spallation neutrons multiplicities, required number of fissions etc.) has been discussed. It has been demonstrated that this method can be insensitive to properties of the zones surrounding the core, whereas is strongly affected by the detector dead time. In turn, the influence of harmonics in the neutron field and of the dispersion of spallation neutrons has proven much less pronounced.


Asunto(s)
Diseño Asistido por Computadora , Modelos Teóricos , Neutrones , Aceleradores de Partículas/instrumentación , Protección Radiológica/instrumentación , Radiometría/métodos , Eliminación de Residuos/instrumentación , Algoritmos , Partículas alfa , Simulación por Computador , Diseño de Equipo , Análisis de Falla de Equipo , Residuos Industriales/prevención & control , Dosis de Radiación , Protección Radiológica/métodos , Eliminación de Residuos/métodos
17.
Thromb Haemost ; 44(3): 161-4, 1980 Dec 19.
Artículo en Inglés | MEDLINE | ID: mdl-6781097

RESUMEN

Human blood platelets cause the collagen gel retraction (CGR) with concomitant exclusion of fluid. CGR is positively related to the number of incorporated platelets and inversely to collagen concentration. Disruption of platelets, EDTA and cytochalasin B inhibit CGR. Platelets from patients with Glanzmann's thrombasthenia are active in CGR. The similarities and differences of CGR and fibrin retraction are discussed.


Asunto(s)
Plaquetas/fisiología , Retracción del Coagulo , Colágeno/fisiología , Adulto , Animales , Colchicina/farmacología , Citocalasina B/farmacología , Depresión Química , Ácido Edético/farmacología , Geles , Humanos , Técnicas In Vitro , Púrpura Trombocitopénica/sangre , Púrpura Trombocitopénica/genética , Conejos , Piel
18.
Thromb Haemost ; 53(3): 377-80, 1985 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-2931854

RESUMEN

Quantitation of fibronectin (FN) concentration is strongly influenced by FN fragmentation with trypsin, kallikrein and plasmin. Digestion by trypsin and kallikrein leads to a progressive decline in FN detectability by the immunoturbidimetric technique to zero values but is associated with an increase in the height of rockets in the Laurell's electroimmunoassay. Plasmin mediated FN fragmentation induces a strong overestimation of the FN content by the electroimmunoassay and, at very high enzyme concentrations, provokes an underestimation of FN by the immunoturbidimetric technique. The decline in FN reactivity in the immunoturbidimetric assay coincides with the disappearance of heavy fractions migrating only slightly faster than native FN in SDS-PAGE. The increase in the height of rockets in the electroimmunoassay is the highest when fractions of intermediate rate of migration prevail in the SDS-PAGE pattern. Concomitant use of these two immunoassays can distinguish native FN from its degraded form and may possibly provide a partial explanation for discrepancies in published studies on the concentration of circulating FN in various pathological states.


Asunto(s)
Fibronectinas/sangre , Péptido Hidrolasas/metabolismo , Anticuerpos , Electroforesis en Gel de Poliacrilamida , Fibrinolisina/metabolismo , Fibronectinas/aislamiento & purificación , Humanos , Inmunoensayo/métodos , Inmunoelectroforesis/métodos , Calicreínas/metabolismo , Nefelometría y Turbidimetría/métodos , Trombina/metabolismo , Tripsina/metabolismo
19.
Thromb Haemost ; 50(4): 768-72, 1983 Dec 30.
Artículo en Inglés | MEDLINE | ID: mdl-6320486

RESUMEN

Two highly purified neutral proteases from human leukocytes i.e. elastase-like protease (ELP) and chymotrypsin-like protease (CLP) do not destroy human platelets since no difference was found in 51Cr liberation from control and enzyme-treated platelets. As with pancreatic chymotrypsin (alpha-CT) ELP does not induce the release of 3H-serotonin while CLP provokes 3H-serotonin secretion, in an enzyme concentration and time dependent fashion. The rate and degree of 3H-serotonin release by CLP is similar to that produced by thrombin. Incubation of platelets at 37 degrees C for 30 min with alpha-CT or ELP renders them resistant to thrombin-releasing activity. Thrombin did not liberate any additional label from platelets which lost over 60% of serotonin during the preceding incubation with CLP. alpha-CT and ELP do not aggregate platelets either in the presence or absence of apyrase. CLP does aggregate platelets suspended in Tyrode buffer without apyrase but not in the presence of apyrase (100 mg/l). The action of alpha-CT, ELP and CLP on washed platelets induces a progressive prolongation of lag phase and a decrease in changes of light transmission during aggregation by thrombin. Similarly to alpha-CT-treated platelets, those subjected to CLP action aggregate in the presence of human fibrinogen. It is concluded that: (1) neutral proteases possibly contribute to development of defects in platelet function in pathological states associated with liberation of leukocyte content into the circulation, (2) CLP similarly to alpha-CT, exposes fibrinogen receptors but in contrast to alpha-CT, CLP aggregates platelets and stimulates serotonin secretion.


Asunto(s)
Plaquetas/efectos de los fármacos , Catepsinas/farmacología , Leucocitos/enzimología , Elastasa Pancreática/farmacología , Péptido Hidrolasas/farmacología , Catepsina G , Catepsinas/aislamiento & purificación , Quimotripsina/farmacología , Fibrinógeno , Humanos , Técnicas In Vitro , Elastasa Pancreática/aislamiento & purificación , Péptido Hidrolasas/aislamiento & purificación , Agregación Plaquetaria/efectos de los fármacos , Glicoproteínas de Membrana Plaquetaria , Receptores de Superficie Celular/efectos de los fármacos , Serina Endopeptidasas , Serotonina/metabolismo , Trombina/farmacología
20.
Thromb Haemost ; 64(2): 294-6, 1990 Oct 22.
Artículo en Inglés | MEDLINE | ID: mdl-2270537

RESUMEN

Plasma fibronectin (pFN), von Willebrand factor antigen (vWf:Ag), factor VIII procoagulant activity, fibrinogen, euglobulin lysis time (ELT) and hematocrit were determined in healthy blood donors before and after venostasis as well as after intravenous infusion of 1-deamino-8-D-arginine vasopressin (DDAVP). Both venostasis and DDAVP provoked an increase in vWf:Ag and shortening in the ELT. In contrast, venostasis only but not DDAVP induced an increase in pFN levels which was statistically significant with and without correction for a concomitant hematocrit increment. The results indicate that there is a distinct difference in the patterns of venostasis and DDAVP mediated release of proteins from the vessel wall.


Asunto(s)
Desamino Arginina Vasopresina/farmacología , Fibronectinas/sangre , Hemostasis/fisiología , Adulto , Desamino Arginina Vasopresina/administración & dosificación , Endotelio Vascular/metabolismo , Femenino , Fibronectinas/biosíntesis , Humanos , Infusiones Intravenosas , Masculino , Persona de Mediana Edad , Torniquetes
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