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1.
Arch Biochem Biophys ; 728: 109356, 2022 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-35868535

RESUMO

Experimental autoimmune encephalomyelitis (EAE) is a mouse model of demyelinating diseases, such as multiple sclerosis (MS). MS can be accompanied by autoimmune hepatitis. In this study, nanomechanical, biorheological and histological examinations were carried out by atomic force microscopy (AFM), rheology, and immunofluorescence microscopy to investigate changes in the liver tissue of EAE mice and the effect of natalizumab, a monoclonal antibody against α4-integrin (VLA-4) cell adhesion molecule, used in MS therapy. Liver samples collected from EAE mice in three successive phases of the disease showed inflammatory changes manifested by leukocyte infiltrations and elevated levels of proinflammatory cytokine IL-1ß. Liver stiffness and viscoelasticity increased in the onset phase of EAE, decreased in the peak phase and increased again in the chronic phase to reach the highest values. These changes were not associated with inflammation parameters which increased in the peak phase and decreased to the lowest values in the chronic phase. Moreover, anti-VLA treatment, which reduced the inflammation parameters, had an ambiguous effect on stiffness and viscoelasticity: it increased them in the peak phase but decreased in the chronic phase. The observed discrepancies can result from a complex network of interactions between inflammation and fibrosis, as well as between liver cells and the extracellular matrix influencing the biomechanical properties of the liver tissue.


Assuntos
Encefalomielite Autoimune Experimental , Esclerose Múltipla , Animais , Anticorpos Monoclonais , Modelos Animais de Doenças , Inflamação , Integrina alfa4beta1 , Fígado , Camundongos , Camundongos Endogâmicos C57BL
2.
Arch Biochem Biophys ; 680: 108221, 2020 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-31816310

RESUMO

Experimental autoimmune encephalomyelitis (EAE) is a commonly used mouse model of multiple sclerosis, a chronic inflammatory disease of the central nervous system (CNS) characterized by demyelination leading to brain and spinal cord malfunctions. We postulate that not only biological but also biomechanical properties play an important role in impairements of CNS function. Atomic force microscopy (AFM) was applied to investigate mechanical properties of spinal cords collected from EAE mice in preonset, onset, peak, and chronic disease phases. Biomechanical changes were compared with histopathological alterations observed in the successive phases. The deformability of gray matter did not change, while rigidity of white matter increased during the onset phase, remained at the same level in the peak phase and decreased in the chronic phase. Inflammatory infiltration and laminin content accompanied the tissue rigidity increase, whereas demyelination and axonal damage showed an opposite effect. The increase in white matter rigidity can be regarded as an early signature of EAE.


Assuntos
Encefalomielite Autoimune Experimental/patologia , Esclerose Múltipla/patologia , Medula Espinal/patologia , Animais , Fenômenos Biomecânicos , Modelos Animais de Doenças , Encefalomielite Autoimune Experimental/fisiopatologia , Feminino , Camundongos , Camundongos Endogâmicos C57BL , Esclerose Múltipla/fisiopatologia , Medula Espinal/fisiopatologia
3.
Analyst ; 141(22): 6217-6225, 2016 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-27704077

RESUMO

Various techniques have been already reported to differentiate between normal (non-malignant) and cancerous cells based on their physico-chemical properties. This is relatively simple when studied cancerous cells originate from distant stages of cancer progression. Here, studies on chemical properties of two closely related human melanoma cell lines are presented: WM115 melanoma cells were taken from the vertical growth phase while WM266-4 from the skin metastatic site of the same patient. Their chemical properties were studied by two techniques, namely time-of-flight secondary ion mass spectra (ToF SIMS) and photothermal microspectroscopy (PTMS), used to record mass and photothermal spectra of cells, respectively. In our approach, independently of the spectra type, its full range, i.e. masses and wavenumbers within the range 0-500 kDa and 500-4000 cm-1, underwent a similar methodology for principal component analysis (PCA). PCA outcome shows results groupped depending on the sample type (either WM115 or WM266-4 cells). The results are independent of the method applied to study chemical properties of melanoma cells, indicating that cancer-related changes are large enough to be identified with these techniques and to differentiate between cells originating from vertical growth phase and skin metastatis.


Assuntos
Melanoma/química , Espectrometria de Massa de Íon Secundário , Linhagem Celular Tumoral , Humanos , Íons , Análise de Componente Principal , Propriedades de Superfície
4.
Biochim Biophys Acta Mol Basis Dis ; 1869(7): 166796, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37400000

RESUMO

Multiple sclerosis and its animal model, experimental autoimmune encephalomyelitis (EAE), are often accompanied by optic neuritis associated with neurofilament disruption. In this study, the stiffness of the optic nerve was investigated by atomic force microscopy (AFM) in mice with induced EAE in the successive phases of the disease: onset, peak, and chronic. AFM results were compared with the intensity of the main pathological processes in the optic nerve: inflammation, demyelination, and axonal loss, as well as with the density of astrocytes, assessed by quantitative histology and immunohistochemistry. Optic nerve tissue and serum levels of neurofilament light chain protein (NEFL) were also examined by immunostaining and ELISA, respectively. The stiffness of the optic nerve in EAE mice was lower than that in control and naïve animals. It increased in the onset and peak phases and sharply decreased in the chronic phase. Serum NEFL level showed similar dynamics, while tissue NEFL level decreased in the onset and peak phases, indicating a leak of NEFL from the optic nerve to body fluids. Inflammation and demyelination gradually increased to reach the maximum in the peak phase of EAE, and inflammation slightly declined in the chronic phase, while demyelination did not. The axonal loss also gradually increased and had the highest level in the chronic phase. Among these processes, demyelination and especially axonal loss most effectively decrease the stiffness of the optic nerve. NEFL level in serum can be regarded as an early indicator of EAE, as it rapidly grows in the onset phase of the disease.


Assuntos
Encefalomielite Autoimune Experimental , Esclerose Múltipla , Camundongos , Animais , Encefalomielite Autoimune Experimental/patologia , Esclerose Múltipla/patologia , Filamentos Intermediários/patologia , Nervo Óptico/patologia , Inflamação/metabolismo
5.
Acta Anaesthesiol Scand ; 55(6): 740-8, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21615348

RESUMO

BACKGROUND: The immunomodulatory effects of volatile anaesthetics in vitro and the protective effect of propofol in lung injury spurred us to study the effects of volatile anaesthetics and propofol on lung tissue in vivo. METHODS: Twenty-seven pigs were randomized to 4-h general anaesthesia with propofol (8 mg/kg/h, group P, n=9), sevoflurane [minimum alveolar concentration (MAC)=1.0, group S, n=9) or desflurane (MAC=1.0, group D, n=9). Four healthy animals served as the no-ventilation group. Bronchoalveolar lavage fluid (BALF) was obtained to measure the cell counts, platelet-activating factor acetylhydrolase (PAF-AcH), phospholipase A(2) (PLA(2)) and superoxide dismutase (SOD) activity. Lung tissues were evaluated histologically and for caspase-3 expression. RESULTS: Volatile anaesthetics reduced PAF-AcH levels without affecting PLA(2) activity and resulted in decreased alveolar macrophage and increased lymphocyte counts in BALF (sevoflurane: 29 ± 23%; desflurane: 26 ± 6%, both P<0.05 compared with 4 ± 2% in the no-ventilation group). These findings were accompanied by atelectasis and inflammatory cells' infiltration in the inhalational anaesthetics groups. Also, sevoflurane reduced SOD activity and both sevoflurane and desflurane induced significant caspase-3 expression. In contrast, propofol resulted in a minor degree of inflammation and preserved BALF cells' composition without triggering apoptosis. CONCLUSION: Halogenated anaesthetics seem to trigger an immune lymphocytic response in the lung, inducing significant apoptosis and impairment of PAF-AcH. In contrast, propofol preserves anti-inflammatory and anti-oxidant defences during mechanical ventilation, thus preventing the emergence of apoptosis.


Assuntos
Anestésicos Inalatórios/farmacologia , Anestésicos Intravenosos/farmacologia , Pulmão/efeitos dos fármacos , Propofol/farmacologia , Respiração Artificial , 1-Alquil-2-acetilglicerofosfocolina Esterase/fisiologia , Animais , Anti-Inflamatórios/farmacologia , Apoptose , Líquido da Lavagem Broncoalveolar/química , Líquido da Lavagem Broncoalveolar/citologia , Caspase 3/análise , Hemodinâmica , Pulmão/imunologia , Oxigênio/sangue , Mecânica Respiratória , Superóxido Dismutase/metabolismo , Suínos
6.
J Physiol Pharmacol ; 72(6)2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35377340

RESUMO

Rhabdomyosarcoma (RMS) is the most commonly occurring malignant soft tissue tumor in children. Despite improving its treatment methods, the current outcome in the advanced stages of this tumor is not satisfactory. RMS cells are characterized by abnormal cellular signaling due to the changes in the activity of the tyrosine kinases. Thus, substances blocking the mitogenic signal transmitted by receptors with tyrosine kinase activity raise hopes for inhibition of the uncontrolled cell growth. In this study, we examined the anticancer activity of tyrphostin AG1296, a tyrosine kinase inhibitor that binds to the intracellular domain of the PDGF (platelet-derived growth factor) receptor in human RMS alveolar and embryonal cell lines. We have discovered that tyrphostin AG1296 completely inhibited cell proliferation and effectively inhibited cell viability. Tyrphostin AG1296 induced apoptosis of the RMS cells and significantly inhibited their migration. Additionally, investigated inhibitor slightly inhibited expression of AKT and phosphorylation of ERK in alveolar RMS cells. Importantly, the inhibitor exerted also potent effects on the nanomechanical properties and cytoskeleton organization of RMS cells. To conclude, tyrphostin AG1296 is a promising compound in the treatment of alveolar RMS. Undoubtedly, a better knowledge of receptor pathomechanism of tyrosine kinases may contribute to developing new, more effective ways of RMS treatment.


Assuntos
Rabdomiossarcoma , Tirfostinas , Proliferação de Células , Criança , Humanos , Fosforilação , Rabdomiossarcoma/tratamento farmacológico , Rabdomiossarcoma/patologia , Tirfostinas/farmacologia
7.
Eur Respir J ; 33(6): 1429-36, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19047311

RESUMO

Acute liver failure (ALF) can be complicated by lung dysfunction. The aim of this study was to test the hypothesis that inhibition of oxidative stress through iron chelation with desferrioxamine (DFX) attenuates pulmonary injury caused by ALF. 14 adult female domestic pigs were subjected to surgical devascularisation of the liver and were randomised to a study group (DFX group, n = 7), which received post-operative intravenous infusion of DFX (14.5 mg x kg(-1) x h(-1) for the first 6 h post-operatively and 2.4 mg x kg(-1) x h(-1) until completion of 24 h), and a control group (n = 7). Post-operative lung damage was evaluated by histological and bronchoalveolar lavage fluid (BALF) analysis. DFX resulted in reduced BALF protein levels and tissue phospholipase (PL)A(2) activity. Plasma malondialdehyde and BALF nitrate and nitrite concentrations were lower, while catalase activity in the lung was higher after DFX treatment. PLA(2), platelet-activating factor acetylhydrolase and total cell counts in BALF did not differ between groups. Histological examination revealed reduced alveolar collapse, pneumonocyte necrosis and total lung injury in the DFX-treated animals. DFX reduced systemic and pulmonary oxidative stress during ALF. The limited activity of PLA(2) and the attenuation of pneumonocyte necrosis could represent beneficial mechanisms by which DFX improves alveolar-capillary membrane permeability and prevents alveolar space collapse.


Assuntos
Lesão Pulmonar Aguda/tratamento farmacológico , Desferroxamina/farmacologia , Falência Hepática Aguda/complicações , Lesão Pulmonar Aguda/etiologia , Análise de Variância , Animais , Líquido da Lavagem Broncoalveolar/química , Catalase/metabolismo , Desferroxamina/administração & dosagem , Feminino , Infusões Intravenosas , Malondialdeído/sangue , Necrose , Nitratos/metabolismo , Nitritos/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Fosfolipases A2/metabolismo , Proteínas/metabolismo , Distribuição Aleatória , Suínos
8.
Nanotechnology ; 20(28): 285709, 2009 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-19550007

RESUMO

A traditional photonic-force microscope (PFM) results in huge sets of data, which requires tedious numerical analysis. In this paper, we propose instead an analog signal processor to attain real-time capabilities while retaining the richness of the traditional PFM data. Our system is devoted to intracellular measurements and is fully interactive through the use of a haptic joystick. Using our specialized analog hardware along with a dedicated algorithm, we can extract the full 3D stiffness matrix of the optical trap in real time, including the off-diagonal cross-terms. Our system is also capable of simultaneously recording data for subsequent offline analysis. This allows us to check that a good correlation exists between the classical analysis of stiffness and our real-time measurements. We monitor the PFM beads using an optical microscope. The force-feedback mechanism of the haptic joystick helps us in interactively guiding the bead inside living cells and collecting information from its (possibly anisotropic) environment. The instantaneous stiffness measurements are also displayed in real time on a graphical user interface. The whole system has been built and is operational; here we present early results that confirm the consistency of the real-time measurements with offline computations.


Assuntos
Microscopia/instrumentação , Microscopia/métodos , Lasers
9.
J Cardiovasc Surg (Torino) ; 49(6): 801-8, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19043394

RESUMO

AIM: Patients with depressed left ventricular function are more susceptible to develop postoperative complications after cardiac surgery. The aim of the present study was to examine the effect of severe left ventricular dysfunction on the activation of systemic inflammatory reaction during and after coronary artery bypass grafting (CABG). METHODS: Clinical prospective study; 32 selected patients underwent CABG; 16 patients had depressed left ventricular function before the operation (low ejection fraction [EF] <30%)--Low EF group (study group). Sixteen patients had normal left ventricular function (normal EF, >50%)--Normal EF group (control group). The levels of inflammatory mediators TNF-alpha, IL-6, IL-8 and IL-10 were measured preoperatively, during and after cardiopulmonary bypass (CPB) and 24 hours postoperatively. RESULTS: Higher levels of almost all of inflammatory mediators were detected in patients with depressed left ventricular function compared with patients of normal EF group. IL-6 levels were found statistically significant higher in Low EF group before the induction of anesthesia (P=0.039) and after the administration of protamine (P=0.02). IL-8 levels were found statistically significant higher in Low EF group before the induction of anesthesia (P=0.05), 30 min after the start of CPB (P=0.02), after the administration of protamine (P=0.015) and 24 hours after the end of the operation (P=0.05). No statistically significant differences were demonstrated between the 2 groups of study relative to TNF-alpha and IL-10. CONCLUSION: A greater activation of systemic inflammatory reaction occurred in patients with depressed left ventricular function than in patients with normal cardiac function when they underwent CABG with extracorporeal circulation.


Assuntos
Ponte de Artéria Coronária , Mediadores da Inflamação/sangue , Volume Sistólico , Disfunção Ventricular Esquerda/sangue , Idoso , Ponte de Artéria Coronária/efeitos adversos , Feminino , Humanos , Interleucina-10/sangue , Interleucina-6/sangue , Interleucina-8/sangue , Masculino , Síndrome de Resposta Inflamatória Sistêmica/etiologia , Síndrome de Resposta Inflamatória Sistêmica/fisiopatologia , Fator de Necrose Tumoral alfa/sangue , Disfunção Ventricular Esquerda/fisiopatologia
10.
Clin Hemorheol Microcirc ; 39(1-4): 213-9, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18503128

RESUMO

Rheological properties of erythrocytes from patients with high risk of cardiovascular disease (CVD) were analyzed in relation to individual patient risk factors as well as to the medication. Additionally, comparative statistical analysis was performed considering plasma concentration of the selected mediators of vascular endothelium: 6-keto-prostaglandin F(1alpha) (PGF(1alpha)), sVCAM-1 and E-selectin adhesion molecules and interleukin-6 (IL-6). It was found that antihypertensive therapy with angiotensin-converting enzyme inhibitor (ACEI) is accompanied by improvement of RBC rheology: the increase of deformability and the decrease of aggregability. This improvement is probably mediated by endothelial prostacyclin and nitric oxide which are generated by ACEI. A correlation was observed between RBC deformability/aggregability and the patient's hematocrit level, what implicates that the hematocrit level should be explicitly taken into consideration when investigating rheological properties of erythrocytes. A strong relationship was also found between the plasma concentration of sVCAM-1 and patient's age.


Assuntos
Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/patologia , Eritrócitos/citologia , Reologia/métodos , Idoso , Inibidores da Enzima Conversora de Angiotensina/farmacologia , Selectina E/metabolismo , Epoprostenol/farmacologia , Agregação Eritrocítica , Deformação Eritrocítica , Feminino , Humanos , Interleucina-6/metabolismo , Masculino , Pessoa de Meia-Idade , Fatores de Risco
11.
Data Brief ; 8: 1322-32, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27570811

RESUMO

Data included in this article are associated with the research article entitled 'Protocol of single cells preparation for time-of-flight secondary ion mass spectrometry' (Bobrowska et al., 2016 in press) [1]. This data file contains topography images of single melanoma cells recorded using atomic force microscopy (AFM). Single cells cultured on glass surface were subjected to the proposed sample preparation protocol applied to prepare biological samples for time-of-flight secondary ion mass spectrometry (ToF SIMS) measurements. AFM images were collected step-by-step for the single cell, after each step of the proposed preparation protocol. It consists of four main parts: (i) paraformaldehyde fixation, (ii) salt removal, (iii) dehydrating, and (iv) sample drying. In total 13 steps are required, starting from imaging of a living cell in a culture medium and ending up at images of a dried cell in the air. The protocol was applied to melanoma cells from two cell lines, namely, WM115 melanoma cells originated from primary melanoma site and WM266-4 ones being the metastasis of WM115 cells to skin.

12.
Biochim Biophys Acta ; 1042(2): 217-20, 1990 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-2105748

RESUMO

The metabolism of exogenous platelet-activating-factor was studied in the protozoan Tetrahymena pyriformis in vivo. When the cells are exposed to 1.10(-6) M PAF, the molecule is rapidly metabolized to 1-O-alkyl-2-acyl(long chain)-GPC, a major component of the protozoan membranes. The appearance of lyso-PAF from the first minutes even in low levels provides evidence that deacetylation is an intermediate step. After incubation for 30 min, transformation to aminoethyl phosphonolipids is also observed. The fate of PAF in concentrations 1.5.10(-11) M or 1.10(-8) M PAF, was the same. An amount of PAF depending on the external PAF concentration remained intact in the cell even after 1 h incubation. Our results suggest that the easily cultured protozoan can be a useful model for studying PAF's metabolism.


Assuntos
Fator de Ativação de Plaquetas/metabolismo , Tetrahymena pyriformis/metabolismo , Animais , Cromatografia Líquida de Alta Pressão , Cinética , Espectrofotometria Ultravioleta
13.
Biochim Biophys Acta ; 1170(3): 258-64, 1993 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-8218344

RESUMO

The ciliated protozoan Tetrahymena pyriformis contains platelet-activating factor (PAF) as a physiological minor lipid. Its subcellular localization was found as follows: 13.7% in the pellicles, 24.9% in mitochondria, 56.5% in microsomes and 7.1% in the cytosol. Succinate dehydrogenase was used as marker enzyme. PAF remains cell-associated unless bovine serum albumin is included in the extracellular medium. In this case 15% of total PAF, portion comparable to that found in the pellicles, is released. Investigation of the principal enzymic activities involved in PAF formation showed that PAF-acetyltransferase (2.3.167) is totally absent from the protozoan. This means that the 'remodelling' pathway occurring in pro-inflammatory cells does not contribute in PAF formation in our system. A dithiothreitol (DTT)-insensitive CDPcholine phosphocholinetransferase activity involved in PAF biosynthesis is shown for the first time to be responsible for PAF production in T. pyriformis. It uses exogenous alkyl-acetyl-glycerol as substrate and is saturated over substrate concentration 250 microM. It can also use endogenous lipids as substrate. It is distributed mainly in mitochondria and microsomes, much less is found in the pellicles and it is totally absent from the cytosol. Its insensitivity to DTT, its selectivity to alkyl-acetyl-G and its different distribution compared to the enzymic activity involved in PC formation (EC 2.7.8.2) suggest that a different enzyme, specific for PAF formation (EC2.7.8.16) via the de novo pathway exists in the protozoan.


Assuntos
Diacilglicerol Colinofosfotransferase/metabolismo , Fator de Ativação de Plaquetas/biossíntese , Tetrahymena pyriformis/metabolismo , Acetiltransferases/análise , Animais , Fracionamento Celular , Diacilglicerol Colinofosfotransferase/análise , Fator de Ativação de Plaquetas/análogos & derivados , Frações Subcelulares/metabolismo , Tetrahymena pyriformis/enzimologia
14.
Biochim Biophys Acta ; 1540(2): 127-36, 2001 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-11513974

RESUMO

The cell's cytoskeleton together with the cell membrane and numerous accessory proteins determines the mechanical properties of cell. Any factors influencing cell organization and structure can cause alterations in mechanical properties of cell (its ability for deformation and adhesion). The determination of the local elastic properties of cells in their culture conditions has opened the possibility for the measurement of the influence of different factors on the mechanical properties of the living cells. The effect of the chitosan on the stiffness of the non-malignant transitional epithelial cells of ureter (HCV 29) and the transitional cell cancer of urine bladder (T24) was determined using scanning force microscopy. The investigations were performed in the culture medium (RPMI 1640) containing 10% fetal calf serum in the presence of the microcrystalline chitosan of the three different deacetylation degrees. In parallel, the effect of chitosan on production of lactate and ATP level was determined. The results showed the strong correlation between the decrease of the energy production and the increase in Young's modulus values obtained for the cancer cells treated with chitosan.


Assuntos
Quitina/farmacologia , Bexiga Urinária/efeitos dos fármacos , Membrana Celular/efeitos dos fármacos , Células Cultivadas , Quitina/análogos & derivados , Quitosana , Citoesqueleto/efeitos dos fármacos , Glicólise/efeitos dos fármacos , Humanos , Microscopia de Força Atômica , Células Tumorais Cultivadas
15.
Intensive Care Med ; 31(10): 1401-8, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16044250

RESUMO

OBJECTIVE: The Guillain-Barré syndrome (GBS) is an acute inflammatory polyneuropathy related to autoimmunity. However, no conclusive etiological concept has yet been found. We examined the variation in autoantibodies to lipids in serum of GBS patients in response to the course of the disease but investigated titer modifications during treatment with gamma-globulin. DESIGN AND SETTING: Prospective clinical study in a 14-bed general ICU. PATIENTS: Nine patients with GBS and nine controls were included in the study. MEASUREMENTS AND RESULTS: Four blood samples were obtained before and after treatment. Serum samples, diluted 1:60, were tested by enzyme-linked immunosorbent assay for IgM, IgA, and IgG antibodies to phosphatidylcholine, phosphatidylinositol, cardiolipin, phosphatidic acid, phosphatidylserine, phosphatidylglycerol, phosphatidylethanolamine, sphingomyelin, and gangliosides. Anti-phospholipid antibodies of the IgM, IgA, and IgG families were detected in all GBS patients but in none of the controls. Phosphatidylinositol, cardiolipin, phosphatidylcholine, and phosphatidic acid were the main antigens. All patients developed anti-phosphatidylinositol antibodies of the IgM family and anti-cardiolipin antibodies of the IgA and IgG families. A decrease in the level of anti-phospholipid autoantibodies was observed after 1 day of treatment with gamma-globulin. Two days after ending gamma-globulin administration the IgG antibodies increased again. CONCLUSIONS: Our findings suggest that in GBS there is an extensive immune reaction, which is altered after gamma-globulin treatment. Anti-cardiolipin and anti-phosphatidylinositol antibodies could be useful markers for the response to treatment.


Assuntos
Anticorpos Antifosfolipídeos/sangue , Síndrome de Guillain-Barré/sangue , gama-Globulinas/uso terapêutico , Adulto , Idoso , Estudos de Casos e Controles , Feminino , Síndrome de Guillain-Barré/tratamento farmacológico , Síndrome de Guillain-Barré/imunologia , Humanos , Imunização Passiva , Imunoglobulina A/sangue , Imunoglobulina A/imunologia , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Imunoglobulina M/sangue , Imunoglobulina M/imunologia , Masculino , Pessoa de Meia-Idade , gama-Globulinas/imunologia
16.
FEBS Lett ; 288(1-2): 147-50, 1991 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-1908796

RESUMO

Our study provides evidence for the existence of an acylhydrolase activity in Tetrahymena pyriformis cells, capable of hydrolyzing the sn-2 ester bond of the PAF molecule. This activity is mainly distributed in the microsomal fraction (76.5% of total) and has properties similar to the mammalian PAF-acetylhydrolase since it is Ca(2+)-independent, acid-labile, is inhibited by DFP and PMSF but it is not affected by egg yolk phosphatidylcholine. This microsomal acylhydrolase has apparent Km and Vmax values of 1.56 microM and 373 pmols.mg.min respectively. This is the first report of the existence of a PAF-acetylhydrolase activity in a non-mammalian cell.


Assuntos
Fosfolipases A/metabolismo , Fator de Ativação de Plaquetas/metabolismo , Tetrahymena pyriformis/enzimologia , 1-Alquil-2-acetilglicerofosfocolina Esterase , Animais , Concentração de Íons de Hidrogênio , Isoflurofato/farmacologia , Cinética , Metabolismo dos Lipídeos , Microssomos/metabolismo
17.
J Biochem ; 119(4): 823-7, 1996 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8743588

RESUMO

1-O-Hexadecyl-2-acetyl-sn-glycerol, the immediate precursor of platelet- activating factor (PAF) in its de novo formation, was detected in the protozoon Tetrahymena pyriformis. It was purified from the total lipid extract by TLC, after successive developments in two different solvent systems. Characterization was assessed by (a) gas-liquid chromatography with electron capture detection, and (b) gas chromatography combined with mass spectrometry in selected ion monitoring mode, after derivatization with heptafluorobutyric acid anhydride and tert-butyldimethylchlorosilane/imidazole, respectively. Its quantity was found to be 0.1 nmol/10(7) cells from the GC-MS, using authentic alkylacetylglycerol as external standard. Cell fractionation revealed that alkylacetylglycerol is located exclusively in the microsomal fraction of the protozoon. Previously, we have reported the occurrence of PAF in the microsomal fraction, as well as a dithiothreitol-insensitive CDP-choline: cholinephosphotransferase activity that utilizes exogenous alkylacetylglycerol as substrate in the mitochondrial and microsomal fractions. The above findings indicate that PAF can be formed in the cell by the de novo pathway.


Assuntos
Éteres de Glicerila/análise , Microssomos/química , Tetrahymena pyriformis/química , Animais , Cromatografia Gasosa/métodos , Fluorocarbonos , Éteres de Glicerila/isolamento & purificação , Imidazóis , Indicadores e Reagentes , Fator de Ativação de Plaquetas , Silanos
18.
Intensive Care Med ; 29(4): 555-63, 2003 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12595981

RESUMO

OBJECTIVE: Surfactant offers protection against alveolar collapse and contributes to the local defense mechanism, but it is unclear if surfactant alterations have a role in the development of atelectasis or ventilator-associated pneumonia (VAP). The present study was undertaken to monitor surfactant, as well as biochemical BAL fluid alterations, during the course of VAP and atelectasis in mechanically ventilated patients without primary cardiopulmonary disease, to elucidate the pathogenesis and to differentiate these two entities. DESIGN. Prospective controlled study. SETTING: 14-bed general ICU of a 750-bed University Hospital. PATIENTS: Sixty-one ventilated patients, without primary cardiopulmonary disease-normal initial chest X-ray, satisfactory oxygenation (PaO(2)/FiO(2)>300 mmHg), and expected time of ventilation exceeding 2 weeks-were initially enrolled. Twelve of them developed VAP and eight lobar or segmental atelectasis during the 2-week study period. INTERVENTIONS: An initial BAL was performed in all patients within 48 h from admission. Patients who developed VAP or atelectasis were subjected to a second and third BAL during and after the resolution of VAP or atelectasis, respectively. MEASUREMENTS AND RESULTS: VAP and atelectasis resulted in a significant increase of total protein and markers of inflammation, such as PAF and neutrophils, which partially remitted after their resolution. Large surfactant aggregates, which contribute to surface tension decrease, were significantly reduced during both entities and remained low even after their resolution. CONCLUSIONS: BAL alterations during VAP and atelectasis suggest increased alveolar-capillary permeability, severe surfactant abnormalities, and signs of local inflammatory reaction. These alterations are associated with the observed deteriorated gas exchange and lung mechanics and could predispose to further lung injury in ventilated patients.


Assuntos
Líquido da Lavagem Broncoalveolar/microbiologia , Pneumonia/etiologia , Atelectasia Pulmonar/etiologia , Respiração Artificial/efeitos adversos , Análise de Variância , Broncoscopia , Feminino , Humanos , Masculino , Pneumonia/complicações , Pneumonia/microbiologia , Estudos Prospectivos , Atelectasia Pulmonar/complicações , Surfactantes Pulmonares , Estatísticas não Paramétricas
19.
Intensive Care Med ; 24(4): 296-303, 1998 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9609406

RESUMO

OBJECTIVE: To determine the concentration of proteins and phospholipids, markers of inflammatory reaction such as platelet-activating factor (PAF), and cell alterations in bronchoalveolar lavage (BAL) fluid during the evolution of the acute respiratory distress syndrome (ARDS). DESIGN: Prospective controlled study. SETTING: 14-bed medical-surgical intensive care unit in a 750-bed university teaching hospital. PATIENTS: 19 mechanically ventilated patients, 9 patients with ARDS and 10 patients without cardiopulmonary disease (controls), were eligible for this study. INTERVENTIONS: BAL was performed during the early, intermediate, and late phases of ARDS. MEASUREMENTS AND RESULTS: Total phospholipids and individual phospholipid classes of the surfactant, proteins, PAF, and cells were measured. High levels of PAF, an increase in neutrophils and proteins, and quantitative as well as qualitative alterations in phospholipids in BAL fluid were observed in ARDS patients compared to the control group. PAF, proteins, and neutrophils were higher in early ARDS than in intermediate or late ARDS. The surfactant pool increased in the early phase and decreased in the intermediate or late phase of the syndrome. The qualitative alterations of surfactant consist of reduced phospholipid content in the surfactant structures with good surface properties; moreover, there was a considerable decrease in the percentage of phosphatidylcholine and phosphatidylglycerol, followed by an increase in phosphatidylethanolamine, phosphatidylserine, phosphatidylinositol, and sphingomyelin in all three phases of ARDS compared to the control group. Lysophosphatidylcholine was detectable only in late ARDS. CONCLUSION: Total surfactant phospholipids, surfactant components, and inflammatory markers such as PAF, cells, and proteins were affected in patients with ARDS. These factors, undergoing quantitative alterations during the course of ARDS, could have a significant role in the pathogenesis and evolution of ARDS.


Assuntos
Líquido da Lavagem Broncoalveolar/química , Líquido da Lavagem Broncoalveolar/citologia , Contagem de Leucócitos , Fator de Ativação de Plaquetas/análise , Proteínas/análise , Surfactantes Pulmonares/análise , Síndrome do Desconforto Respiratório/imunologia , Síndrome do Desconforto Respiratório/patologia , Adolescente , Adulto , Idoso , Biomarcadores/análise , Estudos de Casos e Controles , Progressão da Doença , Feminino , Humanos , Inflamação , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Prospectivos , Surfactantes Pulmonares/química , Reprodutibilidade dos Testes , Síndrome do Desconforto Respiratório/mortalidade , Fatores de Tempo
20.
Clin Rheumatol ; 20(2): 91-7, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11346238

RESUMO

The purpose of this study was to investigate the biochemical characteristics as well as the occurrence and specificity of antiphospholipid antibodies in the bronchoalveolar lavage (BAL) fluid from a patient with both antiphospholipid antibodies syndrome (APS) and acute respiratory distress syndrome (ARDS). Proteins, lipids, cells and autoantibodies were determined. Immunoglobulins were purified with affinity chromatography. Autoantibody identification was assessed with enzyme-linked immunosorbent assay (ELISA) and with electrophoresis, followed by immunoblotting and revelation with antihuman IgG-peroxidase conjugate. Antiphospholipid antibodies were found to be present in the BAL fluid as well as in the serum from a patient with APS. Specifically, antiphosphatidylserine and antiphosphatidic acid IgG antibodies in the BAL fluid and antiphosphatidylcholine and anticardiolipin IgG antibodies in the serum were detected at high levels. BAL fluid protein and the percentage of neutrophils were found to be increased. A quantitative as well as qualitative deficiency of surfactant phospholipids was also observed. Antibodies directed against surfactant phospholipids could cause surfactant abnormalities and an inflammatory reaction. These disorders may be one of the causes of the ARDS or a factor in the perpetuation of the inflammation.


Assuntos
Síndrome Antifosfolipídica/patologia , Líquido da Lavagem Broncoalveolar , Síndrome do Desconforto Respiratório/patologia , Adulto , Anticorpos Antifosfolipídeos/análise , Anticorpos Antifosfolipídeos/classificação , Síndrome Antifosfolipídica/complicações , Líquido da Lavagem Broncoalveolar/química , Líquido da Lavagem Broncoalveolar/imunologia , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Síndrome do Desconforto Respiratório/etiologia
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