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1.
Pharmazie ; 77(2): 54-58, 2022 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-35209964

RESUMEN

Multi-targeted tyrosine kinase inhibitors have been developed for the treatment of various cancers, but they are associated with a significant incidence of idiosyncratic drug reactions (IDRs). There is compelling evidence that most IDRs are immune mediated. Activation of inflammasomes is often one of the early steps in the initiation of an immune response. This activation could involve the pharmacological effect of the drug, or it could involve the release of damage associated molecular patters (DAMPs) caused by a reactive metabolite. We tested whether sunitinib, regorafenib, lenvatinib and cabozantinib can directly activate inflammasomes in differentiated THP-1 cells. We found that regorafenib activated the inflammasome of differentiated THP-1 cells directly. We also found that the supernatant from the incubation of sunitinib with FLC-4 cells, which have a high capacity to metabolize drugs, led to activate the inflammasome of differentiated THP-1 cells. In the supernatant of FLC-4 cells with sunitinib, the heat shock protein (HSP) 90 was significantly increased. Sunitinib is known to be oxidized to generate a reactive, potentially toxic quinone imine. These results support the hypothesis that the reactive metabolite of sunitinib can cause the release of DAMPs from hepatocytes, which leads to activation of inflammasomes. Inflammasome activation may be an important step in the activation of the immune system by regorafenib and sunitinib, which in some patients, can cause IDRs.


Asunto(s)
Inflamasomas , Inhibidores de Proteínas Quinasas , Humanos , Compuestos de Fenilurea , Inhibidores de Proteínas Quinasas/efectos adversos , Piridinas , Sunitinib , Células THP-1
2.
Pharmazie ; 71(3): 152-3, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-27183710

RESUMEN

Although hypoxic conditions have been reported to affect the expression levels of various enzymes like cytochrome P450, the effect of hypoxia for UDP-glucuronosyl transferase (UGT) expression has been unclear. We evaluated the mRNA expression of UGTs (UGT1A1·1A6·1A9·2B7) in a functional liver cell-4 (FLC-4) cell line by three-dimensional culture under hypoxic conditions (37 °C, 1% O2, 5% CO2) fo 7 days. The mRNA expression of UGT1A1·1A6·1A9·2B7 decreased significantly after 3 days and that of UGT1A1·1A6·1A9 decreased significantly after 7 days. Hypoxic conditions affect the expression levels of UGT enzymes, thus the adjustment of dosage and interval should be considered in drug therapy that metabolized by UGT.


Asunto(s)
Hipoxia de la Célula , Glucuronosiltransferasa/biosíntesis , Neoplasias Hepáticas Experimentales/enzimología , ARN Mensajero/biosíntesis , Animales , Línea Celular Tumoral , Humanos , Isoenzimas/biosíntesis , Microsomas Hepáticos/enzimología
3.
Phys Rev Lett ; 116(7): 076402, 2016 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-26943548

RESUMEN

To control the efficiency of photoinduced charge-order melting in perovskite manganites, we performed femtosecond pump-probe spectroscopy using double-pulse excitation on Pr_{0.6}Ca_{0.4}MnO_{3}. The results revealed that the transfer of the spectral weight from the near-infrared to infrared region by the second pump pulse is considerably enhanced by the first pump pulse and that the suppression of crystal anisotropy, that is, the decrease of long-range lattice deformations due to the charge order by the first pump pulse is a key factor to enhance the charge-order melting. This double-pulse excitation method can be applied to various photoinduced transitions in complex materials with electronic and structural instabilities.

4.
Phys Rev Lett ; 114(14): 149702, 2015 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-25910168
5.
Phys Rev Lett ; 113(14): 147203, 2014 Oct 03.
Artículo en Inglés | MEDLINE | ID: mdl-25325655

RESUMEN

The nature of near-surface spin canting within Fe3O4 nanoparticles is highly debated. Here we develop a neutron scattering asymmetry analysis which quantifies the canting angle to between 23° and 42° at 1.2 T. Simultaneously, an energy-balance model is presented which reproduces the experimentally observed evolution of shell thickness and canting angle between 10 and 300 K. The model is based on the concept of Td site reorientation and indicates that surface canting involves competition between magnetocrystalline, dipolar, exchange, and Zeeman energies.


Asunto(s)
Nanopartículas de Magnetita/química , Modelos Químicos , Materiales Biocompatibles/química , Óxido Ferrosoférrico/química , Magnetometría/métodos , Propiedades de Superficie , Temperatura , Termodinámica
6.
IEEE Trans Magn ; 49(7): 3449-3452, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25382864

RESUMEN

A linear array of Nd-Fe-B magnets has been designed and constructed in an inverted Halbach configuration for use in separating magnetic nanoparticles. The array provides a large region of relatively low magnetic field, yet high magnetic field gradient in agreement with finite element modeling calculations. The magnet assembly has been combined with a flow channel for magnetic nanoparticle suspensions, such that for an appropriate distance away from the assembly, nanoparticles of higher moment aggregate and accumulate against the channel wall, with lower moment nanoparticles flowing unaffected. The device is demonstrated for iron oxide nanoparticles with diameters of ~ 5 and 20 nm. In comparison to other approaches, the inverted Halbach array is more amenable to modeling and to scaling up to preparative quantities of particles.

7.
Drug Discov Ther ; 5(4): 181-4, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22466298

RESUMEN

We investigated the effects of a Chinese herbal medicine, Gosha-jinki-gan (GJG), on the regulation of insulin levels in rats fed a sucrose-rich diet (SRD). Normal Wistar rats in the SRD group were fed an SRD for 4 weeks. Increased dietary sucrose did not alter plasma glucose levels but it increased plasma insulin levels at 2 and 4 weeks in the SRD-fed rats relative to control rats that were fed standard chow. GJG treatment significantly suppressed the SRD-induced elevation in plasma insulin levels. These results suggest that GJG improves hyperinsulinemia caused by an SRD.

8.
Phys Rev Lett ; 104(20): 207203, 2010 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-20867056

RESUMEN

A new development in small-angle neutron scattering with polarization analysis allows us to directly extract the average spatial distributions of magnetic moments and their correlations with three-dimensional directional sensitivity in any magnetic field. Applied to a collection of spherical magnetite nanoparticles 9.0 nm in diameter, this enhanced method reveals uniformly canted, magnetically active shells in a nominally saturating field of 1.2 T. The shell thickness depends on temperature, and it disappears altogether when the external field is removed, confirming that these canted nanoparticle shells are magnetic, rather than structural, in origin.


Asunto(s)
Magnetismo , Nanopartículas de Magnetita/química , Difracción de Neutrones , Dispersión del Ángulo Pequeño , Temperatura
9.
Phys Rev Lett ; 99(14): 147201, 2007 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-17930712

RESUMEN

In studying well-characterized, exchange-biased Fe(3)O(4)/CoO superlattices, we demonstrate a causal link between the exchange bias effect and the perpendicular coupling of the ferrimagnetic and antiferromagnetic spins. Neutron diffraction studies reveal that for thin CoO layers the onset temperature for exchange biasing T(B) matches the onset of locked-in, preferential perpendicular coupling of the spins, rather than the antiferromagnetic ordering temperature T(N). The results are explained by considering the role of anisotropic exchange first proposed by Dzyaloshinsky and Moriya and developing a model based purely on information on structural defects and exchange for these oxides. The devised mechanism provides a general explanation of biasing in systems with perpendicular coupling.

10.
J Clin Pharm Ther ; 29(6): 565-71, 2004 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-15584945

RESUMEN

OBJECTIVE: To better define the reported increased digitalis-like immunoreactive substances (DLIS) in neonatal plasma, we studied the relation among plasma DLIS level, blank intensity (BLK-I) value at FPIA measurement and plasma total bilirubin level. METHODS: The DLIS levels were measured in 10 neonates with or without jaundice and 10 infants in good health, using fluorescence polarization immunoassay (FPIA) and microparticle enzyme immunoassay (MEIA). BLK-I value and plasma total bilirubin level were also measured simultaneously. RESULTS: In neonates with jaundice, DLIS using FPIA, BLK-I and total bilirubin level were 0.58 +/-0.13 ng/mL, 2598 +/- 408, and 17.98 +/- 1.13 mg/dL, respectively, before phototherapy, and 0.33 +/-0.06 ng/mL, 1886 +/- 237, and 15.16 +/- 2.07 mg/dL after phototherapy. Corresponding values in neonates without jaundice were (DLIS: 0.34 +/-0.04 ng/mL; BLK-I: 1,764 +/- 278; total bilirubin: 10.37 +/- 4.54 mg/dL); in healthy infants (0.12 +/-0.06 ng/mL, 400.7 +/- 4.6 and 0.42 +/- 0.13 mg/dL, respectively) and in healthy volunteers (0.10 +/-0.07 ng/mL, 403.1 +/- 8.4, and 0.58 +/- 0.30 mg/dL, respectively). Using MEIA, DLIS was not detected in 10 neonates, 10 infants and 20 healthy volunteers. CONCLUSIONS: A fluorescent compound related to bilirubin increased the BLK-I value in the measurement of neonatal plasma using FPIA. The fluorescence was not the result of endogenous digitalis-like factors.


Asunto(s)
Digoxina/sangre , Saponinas/sangre , Bilirrubina/sangre , Cardenólidos , Fármacos Cardiovasculares/sangre , Fármacos Cardiovasculares/uso terapéutico , Preescolar , Digoxina/uso terapéutico , Femenino , Inmunoensayo de Polarización Fluorescente/métodos , Cardiopatías/sangre , Cardiopatías/tratamiento farmacológico , Humanos , Lactante , Recién Nacido , Ictericia/sangre , Ictericia/terapia , Masculino , Fototerapia , Valores de Referencia
11.
Br J Nutr ; 90(6): 1031-8, 2003 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-14641962

RESUMEN

The prevention of arterial thrombotic diseases has a high priority in developed countries. An inappropriate diet may be an important risk factor for thrombotic events. The daily intake of an anti-thrombotic diet may offer a convenient and effective way of prevention. The aim of the present study was to test tomato extracts for anti-thrombotic effects and to identify those varieties that have such an effect. A shear-induced platelet-function test (haemostatometry) was used to test anti-thrombotic potential in vitro. Extracts from those tomato varieties that showed a significant anti-thrombotic activity in vitro were further assessed in vivo, using a laser-induced thrombosis test in mice. One tomato variety (KG99-4) showed significant anti-thrombotic activity both in vitro and in vivo. KG99-4 inhibited not only platelet-rich thrombus formation but also had a thrombolytic effect. It is concluded that haemostatometry can detect and classify the anti-thrombotic potential of fruits and vegetables and offers a simple way of screening for such effects.


Asunto(s)
Dieta , Solanum lycopersicum , Trombosis/prevención & control , Animales , Coagulación Sanguínea/efectos de los fármacos , Fibrinolíticos/farmacología , Calor , Rayos Láser , Solanum lycopersicum/clasificación , Masculino , Ratones , Ratones Endogámicos C57BL , Extractos Vegetales/farmacología , Agregación Plaquetaria/efectos de los fármacos , Pruebas de Función Plaquetaria/métodos , Ratas , Ratas Wistar , Especificidad de la Especie , Trombosis/etiología
12.
Blood Coagul Fibrinolysis ; 13(6): 497-504, 2002 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-12192301

RESUMEN

Epidemiological studies suggest the high fat content of the Western diet to be responsible for atherosclerosis and its thrombotic complications. Despite such a prevailing view, few animal experiments have so far succeeded in demonstrating enhanced thrombogenicity due to a high fat diet. Even a high fat and a very high cholesterol (1%) diet has failed to demonstrate an enhanced thrombotic reaction in rodents and rabbits. The aim of the present study was twofold. First, we wanted to establish a new, sensitive and specific thrombosis model in mice, which can then be used to study the effect of diets. Second, we intended to employ such a thrombosis model in investigations into the effect of high or low fat diets on thrombosis. The technique described uses a laser to induce thrombus formation in the exposed carotid artery of apolipoprotein E-deficient and low-density lipoprotein receptor-deficient mice. Thrombus formation was recorded on video, analysed by computer, and the size of thrombus was calculated by image analysis software. Thrombotic status was evaluated by analysing a total of 61 individual images of the thrombotic reaction, which were taken over 600 s. The severity of atherosclerosis was assessed by image analysis of the stained elastic fibers. Two kinds of diets were used: the Western type, high fat diet contained 20% fat (w/w) and 0.05% cholesterol (w/w); the low fat diet contained 7% fat, without cholesterol. These diets were on the basis of AIN93G and were given to mice for 4 or 8 weeks. The high fat diet significantly enhanced both the thrombotic reaction and the development of atherosclerosis as compared with the low fat diet.


Asunto(s)
Dieta Aterogénica , Modelos Animales de Enfermedad , Trombofilia/etiología , Animales , Apolipoproteínas E/deficiencia , Apolipoproteínas E/genética , Arteriosclerosis/etiología , Arterias Carótidas/patología , Arterias Carótidas/ultraestructura , Rayos Láser , Estilo de Vida , Lípidos/sangre , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Receptores de LDL/deficiencia , Receptores de LDL/genética , Trombofilia/sangre , Trombosis/sangre , Trombosis/etiología , Trombosis/patología
13.
Artículo en Alemán | MEDLINE | ID: mdl-12704911

RESUMEN

In recent years the number of the patients with occlusive disease of the peripheral arteries is increasing also in Japan. For such patients there are many methods to make final diagnosis. Among a lot of methods we have chosen color duplex sonography for functional diagnosis in the patients with occlusive disease of the peripheral artery. During 2 years we have investigated color duplex sonography in addition to digital subtraction arteriography for 40 patients (68 limbs) with occlusive disease of the peripheral artery. First of all waveform of blood flow and the systolic velocities of the dorsal- and the posterior tibial arteries as well as the brachial artery were observed and measured. The blood flow volume and the ratio of systolic velocities and flow volume of lower to upper extremity (AVI, AFI) were measured and their values were also analysed in each patient. These data were compared with Fontaine's classification as a clinical symptom. For the patients with Fontaine class I, or II conservative treatments were carried out, and operative interventions such as bypass graft, or endovascular operation were carefully performed for the patients with Fontaine's class III or IV. Consequently, clinical symptoms and waveforms of systolic flow, and its velocity were remarkably improved by surgical interventions. Thus, color duplex sonography was a useful procedure to make diagnosis and to decide operative indication in the patients with occlusive disease of the peripheral artery.


Asunto(s)
Arteriopatías Oclusivas/diagnóstico por imagen , Ultrasonografía Doppler en Color , Adulto , Anciano , Anciano de 80 o más Años , Angiografía de Substracción Digital , Brazo/irrigación sanguínea , Velocidad del Flujo Sanguíneo/fisiología , Femenino , Humanos , Isquemia/diagnóstico por imagen , Pierna/irrigación sanguínea , Masculino , Persona de Mediana Edad , Valores de Referencia , Sensibilidad y Especificidad
14.
Phys Rev Lett ; 84(26 Pt 1): 6102-5, 2000 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-10991134

RESUMEN

The blocking temperature T(B) has been determined as a function of the antiferromagnetic layer thickness in the Fe3O4/CoO exchange biased system. For CoO layers thinner than 50 A, T(B) is reduced below the Néel temperature T(N) of bulk CoO (291 K), independent of crystallographic orientation or film substrate ( alpha-Al2O3, SrTiO3, and MgO). Neutron diffraction studies show that T(B) does not track the CoO ordering temperature and, hence, that this reduction in T(B) does not arise from finite-size scaling. Instead, the ordering temperature of the CoO layers is enhanced above the bulk T(N) for layer thicknesses approximately less than or equal to 100 A due to the proximity of magnetic Fe3O4 layers.

15.
Leukemia ; 14(6): 1052-9, 2000 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10865972

RESUMEN

Interleukin-18 (IL-18) is a new inflammatory cytokine sharing biological functions with IL-12. The human IL-18 receptor (IL-18R) was recently identified and was found to be expressed on normal peripheral blood lymphocytes. To further characterize IL-18R, we analyzed IL-18R expression using a series of human hematopoietic cell lines selected from various cell lineages. We found the IL-18R expression on cells of T and B lineages as expected from analysis on normal cells. The IL-18R expression, however, was found not to be restricted to any specific maturation stages of T and B cells. In addition, we detected IL-18R expression in myeloid, monocytoid, erythroid and megakaryocytic cell lines, indicating that normal counterparts of these cell lineages could express IL-18R and participate in in vivo reactions caused by IL-18. Biochemical studies showed that IL-18R proteins exist as heterogeneous molecules ranging from 60 to 110 kDa. Deglycosylation experiments indicated that the heterogeneity could not be explained only by a difference in glycosylation. We also found that tumor necrosis factor-alpha (TNF-alpha) modulated the IL-18R expression, which implies an important in vivo effect of TNF-alpha on IL-18-induced reaction. Analyzing the responsiveness of IL-18R, we found that only KG-1 responded to IL-18 stimulation. This suggests that certain inhibitory mechanisms of IL-18 responsive genes are involved in the all IL-18R-positive cell lines except KG-1.


Asunto(s)
Células de la Médula Ósea/metabolismo , Receptores de Interleucina/genética , Linfocitos B/inmunología , Western Blotting , Células de la Médula Ósea/inmunología , Línea Celular Transformada , Ensayo de Inmunoadsorción Enzimática , Citometría de Flujo , Glicosilación , Humanos , Interleucina-12/farmacología , Interleucina-18/metabolismo , Subunidad alfa del Receptor de Interleucina-18 , Receptores de Interleucina/metabolismo , Receptores de Interleucina-18 , Linfocitos T/inmunología , Factor de Necrosis Tumoral alfa/farmacología , Regulación hacia Arriba
16.
J Immunol ; 164(6): 3330-6, 2000 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-10706727

RESUMEN

IL-18 is a new type of inflammatory cytokine similar to but distinct from IL-12 and IL-1beta. One intriguing property of IL-18 is synergism with IL-12 in many respects. In this study we examined the in vivo synergistic effects of IL-18/IL-12 in mice and found lethal toxicity accompanying an elevated IFN-gamma level in the serum. Since treatment with IL-18 alone did not have any apparent toxicity, and treatment with IL-12 alone showed only limited toxicity in our system, the synergy between the two cytokines was all the more remarkable. The major symptoms of the toxicity were weight loss, diarrhea, hemorrhagic colitis, splenomegaly, fatty liver, and atrophic thymus, most of which are similarly found in endotoxin-induced septic shock. However, in contrast to septic shock, TNF-alpha was not induced. The involvement of IFN-gamma in the toxicity was further studied in detail. Treatment of athymic nude mice with anti-asialo-GM1 did not reduce the toxicity, whereas anti-IFN-gamma treatment of wild-type mice alleviated it. When IFN-gamma-deficient mice were treated with IL-18/IL-12, the majority of them showed mortality and toxicity with severe pulmonary edema. These results indicate that IL-18/IL-12 treatment induces severe adverse effects through not only IFN-gamma-dependent mechanisms but also IFN-gamma-independent processes.


Asunto(s)
Interferón gamma/inmunología , Interleucina-12/efectos adversos , Interleucina-18/efectos adversos , Animales , Peso Corporal/efectos de los fármacos , Citocinas/biosíntesis , Combinación de Medicamentos , Sinergismo Farmacológico , Femenino , Sueros Inmunes/administración & dosificación , Sueros Inmunes/farmacología , Inyecciones Intraperitoneales , Interferón gamma/administración & dosificación , Interferón gamma/biosíntesis , Interferón gamma/deficiencia , Interleucina-12/administración & dosificación , Interleucina-12/toxicidad , Interleucina-18/administración & dosificación , Interleucina-18/toxicidad , Células Asesinas Naturales/inmunología , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Ratones Noqueados , Ratones Desnudos , Edema Pulmonar/etiología , Edema Pulmonar/inmunología , Edema Pulmonar/mortalidad , Linfocitos T/inmunología
17.
Eur Heart J ; 21(4): 296-305, 2000 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10653677

RESUMEN

AIMS: Although increased digitalis-like immunoreactive substances have been found in cases of hypertension and heart failure, no information is available about digitalis-like immunoreactive substances in patients with hypertrophic cardiomyopathy. We investigated digitalis-like immunoreactive substances in the plasma and biopsied specimens of patients with hypertrophic cardiomyopathy. METHODS AND RESULTS: In 40 patients with hypertrophic cardiomyopathy (27 with the non-obstructive type and 13 with the obstructive type), the plasma concentration of digitalis-like immunoreactive substances was studied by fluorescence polarization immunoassay. Right ventricular endomyocardial biopsy specimens were analysed immunohistochemically, using a monoclonal antibody against digoxin. An increase in digitalis-like immunoreactive substances of more than 0.2 ng. ml(-1)in plasma was found in six of 27 patients with non-obstructive hypertrophic cardiomyopathy (22.2%) and five of 13 with obstructive hypertrophic cardiomyopathy (38.4%). Under light microscopy, positive staining against the antibody was observed heterogeneously on some cardiocytes. In non-obstructive hypertrophic cardiomyopathy, digitalis-like immunoreactive substances in the plasma correlated with the left atrial dimension and inversely with the cardiac index. In obstructive hypertrophic cardiomyopathy, plasma and myocardial digitalis-like immunoreactive substances were positively correlated; they also correlated with left ventricular end-diastolic pressures. Under electron microscopy, digitalis-like immunoreactive substances were detected at the sarcolemma in the free wall, T-tubules, intercalated discs and Z-bands of cardiocytes. CONCLUSIONS: Increased digitalis-like immunoreactive substances in plasma and cardiocytes, which may have been caused by pressure and/or volume overload, were found in patients with hypertrophic cardiomyopathy. Digitalis-like immunoreactive substances may act on the sarcolemma of cardiocytes and be transported into the cytoplasm.


Asunto(s)
Cardiomiopatía Hipertrófica/sangre , Digoxina , Miocardio/metabolismo , Saponinas/sangre , ATPasa Intercambiadora de Sodio-Potasio/antagonistas & inhibidores , Adulto , Anciano , Anticuerpos Monoclonales , Cardenólidos , Cardiomiopatía Hipertrófica/fisiopatología , Femenino , Inmunoensayo de Polarización Fluorescente , Hemodinámica , Humanos , Inmunohistoquímica , Masculino , Persona de Mediana Edad , Miocardio/citología
19.
Int J Exp Pathol ; 75(6): 441-51, 1994 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-7734333

RESUMEN

Bacteria, or the culture supernatants of an elastase non-producing strain of Pseudomonas aeruginosa, elicited a chemotactic response from polymorphonuclear leucocytes (PMN) in vitro. The chemoattractive capacity was diminished under the presence of Boc-Phe-Leu-Phe-Leu-Phe, a receptor antagonist of N-formyl-Met-Leu-Phe (fMLP) which is a bacterial chemotactic peptide to PMN. This indicated that the chemoattractant derived from Pseudomonas aeruginosa was a fMLP-like molecule(s). In contrast, culture supernatants of an elastase producing strain of Pseudomonas aeruginosa produced negligible chemotactic response from PMN. Indeed, an inhibitory effect of the culture supernatants or of purified Pseudomonas aeruginosa elastase (PAE) on PMN chemotaxis was observed when fMLP was used as a chemoattractant. Another fMLP-induced function of PMN, respiratory burst activation, was also diminished by pretreatment of PMN with PAE. PAE hydrolysed fMLP at the Met-Leu bond and diminished the chemoattractant capacity. In addition, a receptor analysis with fML-3H-P demonstrated a decrease in numbers of fMLP receptors on PMN without changing the dissociation constant values after the treatment of the cells with PAE. In the primary structure of the fMLP receptor previously reported, a preferential amino acid sequence for cleavage by PAE was identified in what was believed to be an extracellular portion of the receptor molecule. These results suggested that PAE could diminish PMN infiltration in response to Pseudomonas aeruginosa in vivo by cleavage of the fMLP-like pseudomonal chemotactic ligand and the receptors on PMN.


Asunto(s)
Absceso/enzimología , Proteínas Bacterianas , Quimiotaxis de Leucocito/efectos de los fármacos , Queratitis/enzimología , Metaloendopeptidasas/farmacología , Pseudomonas aeruginosa/enzimología , Medios de Cultivo Condicionados , Humanos , Hidrólisis/efectos de los fármacos , Modelos Biológicos , N-Formilmetionina Leucil-Fenilalanina/farmacología , Neutrófilos/fisiología , Infecciones por Pseudomonas/enzimología , Pseudomonas aeruginosa/clasificación , Receptores de Formil Péptido , Receptores Inmunológicos/efectos de los fármacos , Receptores de Péptidos/efectos de los fármacos
20.
Graefes Arch Clin Exp Ophthalmol ; 231(9): 521-8, 1993 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-8224956

RESUMEN

In order to identify the causative factors of ring abscess, which is the characteristic feature of pseudomonal keratitis, pseudomonal endotoxin, exotoxin A, and elastase were each separately injected into guinea pig cornea. There was no formation of ring abscess. Injection of living Pseudomonas aeruginosa strains IFO3455 and Takamatsu which produce all three molecules, clearly induced ring abscess. In contrast, when heat-killed bacteria strain IFO3455 or living bacteria of the non-elastase-producing strain PA103 were injected, ring abscess was not induced. Furthermore, when living bacteria strain IFO3455 were injected with anti-elastase antibody or a protease inhibitor, ovomacroglobulin, ring abscess formation was significantly inhibited. Histological examination demonstrated that the ring abscess was a dense accumulation and aggregation of polymorphonuclear leukocytes (PMN) with debris of cells and lamellae in the deep stroma at the corneal margins, suggesting prevention of PMN migration to the central lesion. The presence of anti-elastase antibody or a specific elastase inhibitor facilitated PMN migration towards living bacteria strain IFO3455 in an in vitro model. These results indicate that pseudomonal elastase is a necessary but not sufficient factor in the formation of ring abscess in pseudomonal keratitis.


Asunto(s)
ADP Ribosa Transferasas , Absceso/microbiología , Toxinas Bacterianas , Infecciones Bacterianas del Ojo , Queratitis/microbiología , Elastasa Pancreática/fisiología , Infecciones por Pseudomonas , Pseudomonas aeruginosa/enzimología , Factores de Virulencia , Absceso/patología , Animales , Córnea/patología , Endotoxinas/fisiología , Exotoxinas/fisiología , Femenino , Cobayas , Queratitis/patología , Masculino , Conejos , Exotoxina A de Pseudomonas aeruginosa
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