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1.
J Stomatol Oral Maxillofac Surg ; 119(1): 16-18, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29030281

RESUMEN

INTRODUCTION: Temporomandibular joint internal derangement is a common disorder, which usually resolves with conservative management. However, 5% of patients require surgery and although many techniques have been described, a gold standard surgical procedure has not yet been established. OBJECTIVES: The aim of this study was to compare the clinical outcome of disc repositioning plus temporal eminectomy versus disc repositioning alone, for the treatment of temporomandibular joint internal derangement. METHODOLOGY: Matched case-control retrospective pilot study. Records of patients diagnosed with temporomandibular joint internal derangement from January 2010 to December 2015 were studied. Eleven patients treated with disc repositioning plus temporal eminectomy for the case group and 11 patients treated with disc repositioning alone for the age- and gender-matched control group. RESULTS: No difference was found in terms of pain, noise or blockage with the maximum oral opening between the groups at the first or sixth month after surgery. However, there were differences in movement restriction at the first and sixth month after surgery, in favor of the temporal eminectomy group. These differences were statistically significant only at the sixth month after surgery (P: 0.03). CONCLUSIONS: Our results suggest that disc repositioning plus temporal eminectomy could be a short-term benefit in terms of mobility and oral opening. However, larger samples and prospective trials will be necessary to corroborate the current findings.


Asunto(s)
Luxaciones Articulares , Disco de la Articulación Temporomandibular , Humanos , Proyectos Piloto , Estudios Prospectivos , Estudios Retrospectivos , Resultado del Tratamiento
2.
Phys Rev Lett ; 102(13): 132501, 2009 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-19392349

RESUMEN

High-precision Penning-trap mass measurements of the N approximately Z approximately 34 nuclides 68Se, 70Se, (70m)Br, and 71Br were performed, reaching experimental uncertainties of 0.5-15 keV. The new and improved mass data together with theoretical Coulomb displacement energies were used as input for rp process network calculations. An increase in the effective lifetime of the waiting point nucleus 68Se was found, and more precise information was obtained on the luminosity during a type I x-ray burst along with the final elemental abundances after the burst.

3.
Phys Rev Lett ; 100(13): 132501, 2008 Apr 04.
Artículo en Inglés | MEDLINE | ID: mdl-18517939

RESUMEN

A new long-lived isomeric state in (65)Fe has been discovered with Penning trap mass spectrometry and high-precision mass measurements of the neutron-rich isotopes (63-65)Fe and (64-66)Co have been performed with the Low-Energy Beam and Ion Trap Facility at the NSCL. For the new isomer in (65)Fe an excitation energy of 402(5) keV has been determined from the measured mass difference between the isomeric and ground states. The mass uncertainties of all isotopes have been reduced by a factor of 10-100 compared to previous results. In the case of (64)Co the previous mass value was found to deviate by about 5 standard deviations from the new measurement.

4.
Phys Rev Lett ; 100(18): 182501, 2008 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-18518366

RESUMEN

The extended radius of a halo nuclide is very sensitive to the minute binding energy of its valence nucleons. The binding energy of 11Li has been measured with high precision by using the radio-frequency spectrometer MISTRAL at CERN's ISOLDE facility. The new two-neutron separation energy of 378+/-5 keV is 25% higher than the previously accepted value with an uncertainty 5 times smaller.

5.
Pathol Biol (Paris) ; 55(5): 246-55, 2007 Jun.
Artículo en Francés | MEDLINE | ID: mdl-16631319

RESUMEN

Active Denial Systems (ADS) is a millimetric wave radiation emitting technology now included in the non lethal weapon arsenal. Such devices emit electromagnetic, thus agitating water in the skin and causing feeling of heat enough that target individual retreats from the beam. They can be used at up to 1 km from the target. We have reviewed the literature on the interactions of millimetric waves (MMW) with biological systems. An opposition appears between the observations performed in the Former Soviet Union and Russia showing potential interaction sometimes deleterious while generally of good influence and used in therapy. By way of contrast, most of the other studies, performed in USA, address local acute effects, exclusively located on the skin and eyes of the target, and considered as completely reversible.


Asunto(s)
Campos Electromagnéticos , Exposición a Riesgos Ambientales , Estudios de Seguimiento , Humanos , Ondas de Radio , Factores de Tiempo , U.R.S.S.
6.
Transplant Proc ; 38(7): 2321-3, 2006 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-16980079

RESUMEN

Parvovirus B19 (PV B19) infection is known to cause acute anemia in solid organ transplant recipients. Intravenous immunoglobulin combined with reduction of immunosuppression may be of benefit to clear the infection. However, PV B19-associated anemia can be recurrent. We describe three renal transplant recipients with a PV B19 infection. These patients showed recurrent anemia with episodes separated by as much as several months.


Asunto(s)
Anemia/virología , Trasplante de Riñón/efectos adversos , Infecciones por Parvoviridae/diagnóstico , Parvovirus B19 Humano , Adulto , Transfusión Sanguínea , Femenino , Humanos , Inmunoglobulinas Intravenosas/uso terapéutico , Terapia de Inmunosupresión/métodos , Enfermedades Renales/cirugía , Masculino , Persona de Mediana Edad , Recurrencia , Factores de Tiempo
7.
Pharmazie ; 56(2): 125-32, 2001 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11234339

RESUMEN

Two pyrido[1,2-e]purins with different side chain lengths have been synthesized to test their ability to intercalate inside DNA. The interactions of these drugs with synthetic oligodeoxy nucleotide d(CGATCG)2 have been studied with 1H and 31P NMR spectroscopy experiments. Molecule 1, rather amphiphilic (Log(P) = 1.3, due to its hydroxypropyl side chain) can intercalate GC sites of the mini helix, under a fast exchange mechanism and a 2:1 stoechiometry. The presence of a six methylen side chain in 2 (hydroxyhexyl side chain) is responsible for a relatively poor solubility of this molecule in water (log P = 2.3). Binding, rather than intercalation, of 2 to the external GC pairs is observed, severely limited by the formation of aggregates. Models for the intercalation of 1, are proposed using energy minimizations and Molecular Dynamics (MD) calculations subject to restraints from experimental nOe connectivities. Simulations and experiments both indicate fast exchange of 1 in its intercalation site.


Asunto(s)
Sustancias Intercalantes/síntesis química , Purinas/síntesis química , ADN/efectos de los fármacos , Enlace de Hidrógeno , Sustancias Intercalantes/química , Espectroscopía de Resonancia Magnética , Modelos Moleculares , Oligonucleótidos/síntesis química , Oligonucleótidos/farmacología , Protones , Purinas/química , Solventes
8.
J Comp Neurol ; 425(1): 45-57, 2000 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-10940941

RESUMEN

Earlier studies have demonstrated overexpression of NT1 neurotensin receptors in rat brain during the first 2 weeks of life. To gain insight into this phenomenon, we investigated the identity and distribution of NT1 receptor proteins in the brain of 10-day-old rats by using two different NT1 antibodies: one (Abi3) directed against the third intracellular loop and the other (Abi4) against the C-terminus of the receptor. Immunoblot experiments that used Abi3 revealed the presence of two differentially glycosylated forms of the NT1 receptor in developing rat brain: one migrating at 54 and the other at 52 kDa. Whereas the 54-kDa form was expressed from birth to adulthood, the 52-kDa form was detected only at 10 and 15 days postnatal. Only the 52-kDa isoform was recognized by Abi4. By immunohistochemistry, both forms of the receptor were found to be predominantly expressed in cerebral cortex and dorsal hippocampus, in keeping with earlier radioligand binding and in situ hybridization data. However, whereas Abi4 immunoreactivity was mainly concentrated within nerve cell bodies and extensively colocalized with the Golgi marker alpha-mannosidase II, Abi3 immunoreactivity was predominantly located along neuronal processes. These results suggest that the transitorily expressed 52-kDa protein corresponds to an immature, incompletely glycosylated and largely intracellular form of the NT1 receptor and that the 54-kDa protein corresponds to a mature, fully glycosylated, and largely membrane-associated form. They also indicate that antibodies directed against different sequences of G-protein-coupled receptors may yield isoform-specific immunohistochemical labeling patterns in mammalian brain. Finally, the selective expression of the short form of the NT1 receptor early in development suggests that it may play a specific role in the establishment of neuronal circuitry.


Asunto(s)
Química Encefálica , Encéfalo/crecimiento & desarrollo , Ratas Sprague-Dawley/fisiología , Receptores de Neurotensina/química , Animales , Especificidad de Anticuerpos , Células COS , Proteínas de Unión al GTP/análisis , Immunoblotting , Inmunohistoquímica , Isomerismo , Masculino , Microscopía Confocal , Ratas , Receptores de Neurotensina/genética , Receptores de Neurotensina/inmunología , Transfección
9.
Arch Biochem Biophys ; 367(2): 202-15, 1999 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-10395736

RESUMEN

Three pyrido[1,2-e]purines of increasing hydrophilicity have been synthesized to evaluate as anticancer agents. These drugs interact quite differently with a synthetic oligodeoxynucleotide d(CGATCG)2. [1] is very hydrophobic due to a phenyl residue in its side chain. It only shows limited interactions with the minihelix without any evidence of intercalation. [2] and [3], on the other hand, have one ([2]) or two ([3]) hydroxyl groups in their acyl chain and present rather amphiphilic properties. The result is a similar intercalation of these derivatives between C and G base pairs as revealed by intermolecular nOe, 1H and 31P chemical shift variations. Models for the intercalation of [2] are proposed using energy minimizations and molecular dynamics (MD) calculations subject to restraints from nOe connectivities. Simulations and experiments indicate weak stability and thus fast exchange of [2] in its intercalation site.


Asunto(s)
Antineoplásicos/síntesis química , Oligonucleótidos/metabolismo , Purinas/química , Purinas/metabolismo , Sulfonamidas/química , Sulfonamidas/metabolismo , Animales , Línea Celular , Sustancias Intercalantes/metabolismo , Cinética , Espectroscopía de Resonancia Magnética , Ratones , Modelos Moleculares , Músculo Esquelético/metabolismo , Pruebas de Mutagenicidad , Conformación de Ácido Nucleico , Protones , Purinas/síntesis química , Sulfonamidas/síntesis química
10.
Eur J Neurosci ; 9(7): 1483-7, 1997 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-9240405

RESUMEN

Neurotensin is present in high quantity in the hypothalamus, where it regulates pituitary hormone secretion. A relationship between dopaminergic and neurotensinergic systems has been suggested in the hypothalamus in studies showing an effect of neurotensin on tuberoinfundibular dopaminergic neurons. In order to determine the anatomical basis of such interactions, primary cultures of rat hypothalamic neurons were used. Tyrosine hydroxylase and neurotensin containing cells were identified by immunocytochemistry and neurotensin binding sites by [125I]Tyr3-neurotensin autoradiography. Colocalization studies showed that neurotensin immunoreactivity was present in 16% of tyrosine hydroxylase-positive cells, and that these neurotensin/tyrosine hydroxylase neurons represented more than half (58%) of the neurotensinergic population. Five percent of the tyrosine hydroxylase-positive cells had neurotensin binding sites, suggesting that only a restricted number of hypothalamic dopaminergic neurons is responsive to neurotensin. Neurotensin binding sites were also found on some neurotensin-positive cells, demonstrating for the first time the presence of autoreceptors for this peptide on neurons. These results in primary cultures provide a cellular basis for direct effects of neurotensin on a subpopulation of hypothalamic dopaminergic cells, and support the possibility of an autocrine action of neurotensin in the hypothalamus.


Asunto(s)
Autorreceptores/metabolismo , Hipotálamo/metabolismo , Neuronas/metabolismo , Neurotensina/metabolismo , Receptores de Neurotensina/metabolismo , Tirosina 3-Monooxigenasa/metabolismo , Animales , Autorradiografía , Sitios de Unión , Células Cultivadas , Hipotálamo/citología , Inmunohistoquímica , Ratas/embriología , Ratas Wistar
11.
J Neuroendocrinol ; 8(8): 587-93, 1996 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-8866245

RESUMEN

Neurotensin (NT) has been shown to be involved in neuroendocrine regulation, and the presence of both the peptide and its receptors has been demonstrated in the hypothalamus. In the present study, we show that hypothalamic neurons in primary cultures express the neurotensin receptor (NTR) and we examined a possible regulation of this receptor by glucocorticoids and activators of adenylate cyclase. In the hypothalamic cultures, 125I-NT bound to a single class of binding sites, presenting a selectivity similar to that observed for the high-affinity NTR previously described in the adult rat brain. Radioautographic studies demonstrated that these 125I-NT binding sites were present on 3% of the neurons. A 48-h treatment with forskolin (fsk) decreased 125I-NT binding by 30%. No effect of dexamethasone (dex) alone was found on that parameter. However, a combined treatment with both agents led to a 40% decrease in 125I-NT binding, corresponding to a reduced number of binding sites, and to a 68% decrease in the amount of NTR mRNA. In parallel, the dex plus forsk treatment increased NT release in the incubation medium. Moreover, the decreases in 125I-NT binding and NTR mRNA induced by this treatment were abolished in the presence of an anti-NT antibody or SR 48692, a non-peptidic antagonist of NTR, suggesting that the down-regulation of NTR observed after dex plus fsk treatment was mediated by the release of endogenous NT. Agonist-induced down-regulation of the NTR in this system was confirmed by the application of an exogenous NT analogue, JMV 449. The present findings indicate that, in hypothalamic cultures, dex and fsk indirectly down-regulate NTR expression via the release of endogenous NT.


Asunto(s)
Colforsina/farmacología , Dexametasona/farmacología , Glucocorticoides/farmacología , Hipotálamo/efectos de los fármacos , Neurotensina/fisiología , Receptores de Neurotensina/efectos de los fármacos , Análisis de Varianza , Animales , Células Cultivadas , Regulación hacia Abajo/efectos de los fármacos , Hipotálamo/química , Hipotálamo/citología , Inmunoglobulinas/inmunología , Neuronas/efectos de los fármacos , Ratas , Ratas Wistar , Receptores de Neurotensina/análisis , Receptores de Neurotensina/inmunología
12.
Boll Chim Farm ; 135(3): 192-8, 1996 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-8974421

RESUMEN

Three potentially antiviral imidazo[1,2-a]pyridine derivatives of increasing hydrophilicity were tested in their interactions with model membranes and synthetic oligonucleotides. It was shown that the most hydrophobic derivative [1], located in the depth of the bilayer only induces minor membrane damages. The molecule [2], only poorly hydrophobic, integrates also the bilayer in the medium part of the chains while the most hydrophilic [3] exhibits fluidizing and slightly detergent properties. In the presence of synthetic oligonucleotide ACATGT no intercallation of the three derivatives was evidenced. By considering their antiviral activity in the absence of evident mitogenic properties, another mechanism of action was proposed.


Asunto(s)
Antivirales/química , Imidazoles/química , Piridinas/química , Membrana Dobles de Lípidos/química , Espectroscopía de Resonancia Magnética , Membranas Artificiales , Oligonucleótidos/química
13.
J Allergy Clin Immunol ; 97(3): 788-99, 1996 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-8613636

RESUMEN

We investigated whether allergen-induced eosinophil recruitment into mouse airways modifies the in vivo bronchopulmonary responses to standard agonists, and adaptation of a technique described for larger animals. Swiss, CBA, and IL-5 transgenic mice were immunized with ovalbumin and challenged intranasally after 14 days. Immunization alone was followed by increased eosinophil counts in bone marrow and blood, whereas antigenic challenge induced eosinophil infiltration in lungs and bronchoalveolar lavage fluid, which was suppressed by dexamethasone. Despite the high eosinophil counts, no bronchopulmonary hyperreactivity to methacholine or serotonin was detected 3 to 96 hours after antigenic provocation. Our results demonstrate that immunization augments the production of eosinophils by mice, which is further increased by antigenic challenge, but that eosinophil overproduction and lung infiltration, per se, are not sufficient to induce bronchopulmonary hyperreactivity, even in constitutively hypereosinophilic IL-5 transgenic mice.


Asunto(s)
Hiperreactividad Bronquial/inmunología , Movimiento Celular/inmunología , Eosinófilos/inmunología , Interleucina-5/genética , Interleucina-5/inmunología , Ovalbúmina/administración & dosificación , Ovalbúmina/inmunología , Resistencia de las Vías Respiratorias/efectos de los fármacos , Resistencia de las Vías Respiratorias/inmunología , Animales , Células de la Médula Ósea , Hiperreactividad Bronquial/sangre , Hiperreactividad Bronquial/genética , Pruebas de Provocación Bronquial , Líquido del Lavado Bronquioalveolar/citología , Movimiento Celular/efectos de los fármacos , Dexametasona/farmacología , Eosinofilia/sangre , Eosinofilia/genética , Eosinofilia/inmunología , Eosinófilos/efectos de los fármacos , Rendimiento Pulmonar/efectos de los fármacos , Rendimiento Pulmonar/inmunología , Masculino , Cloruro de Metacolina , Ratones , Ratones Endogámicos CBA , Ratones Transgénicos , Serotonina/farmacología , Especificidad de la Especie
14.
J Pharm Sci ; 85(2): 200-5, 1996 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-8683449

RESUMEN

Crucial conditions for the pharmacological use of active compounds are their ability to cross the biological barriers and reach their intracellular target. In the case of two antiviral pyridopurine derivatives, 1 and 2, this included essentially the membranes and the nucleic acids. Thus the interactions of 1 and 2 with model membranes and oligonucleotides were studied using NMR spectroscopy. It was found that these hydrophobic molecules can be incorporated into the model membranes at the terminal methyl group level, inducing dynamic perturbations in the bilayer. In the presence of the synthetic oligonucleotide ACATGT, both molecules can intercalate aspecifically in AT and GC systems. Inclusion complexes of 1 and 2 beta-cyclodextrins with a 1:1 stoichiometry, were also prepared. This led to to propose two galenic forms 1 and 2, i.e. included in phospholipid vesicles in the form of a beta-cyclodextrin complex


Asunto(s)
Aminas/química , Ciclodextrinas/química , Preparaciones Farmacéuticas/química , Dimiristoilfosfatidilcolina/química , Alimentos , Espectroscopía de Resonancia Magnética
15.
Am J Respir Cell Mol Biol ; 11(4): 386-96, 1994 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-7917307

RESUMEN

In order to characterize the response of various pulmonary cell types to polycyclic aromatic hydrocarbons, the expression of cytochrome P450 (CYP) 1A1 and 2B1 mRNA in the lung of rats, with or without induction by 3-methylcholanthrene (3MC), was analyzed by in situ hybridization using appropriate 35S-labeled riboprobes. The expression of the corresponding proteins was investigated immunohistochemically. Following induction with 3MC, the kinetics of mRNA expression differed considerably between Clara cells and type II pneumocytes and venous endothelial cells. In Clara cells, mRNA expression was detected as early as 1 h after induction, peaked between 2 and 4 h, and was completely undetectable at 14 h. In contrast, venous endothelial cells and type II pneumocytes exhibited permanent mRNA expression of CYP 1A1 in 3MC-pretreated rats. These kinetic results explain the striking absence of correlation between mRNA and protein expression observed in Clara cells 24 h after the end of the induction protocol, as these cells exhibited intense protein expression with no mRNA. In contrast, a good correlation was observed for mRNA and protein expression of CYP 2B1, with similar expressions for Clara cells and type II pneumocytes, but no expression in endothelial cells. This study clearly distinguished the regulation of CYP 1A1 expression in the rat lung from that described in the liver. The differences observed in the various lung cell types, whatever the post-transcriptional mechanisms involved, emphasize that studies must be performed at the cellular level in order to understand the specific response to xenobiotics, not only of this organ as a whole but also of its various anatomic structures.


Asunto(s)
Hidrocarburo de Aril Hidroxilasas , Sistema Enzimático del Citocromo P-450/biosíntesis , Regulación Enzimológica de la Expresión Génica , Pulmón/enzimología , Metilcolantreno/farmacología , Esteroide Hidroxilasas/biosíntesis , Secuencia de Aminoácidos , Animales , Autorradiografía , Northern Blotting , Sistema Enzimático del Citocromo P-450/análisis , Sistema Enzimático del Citocromo P-450/genética , Inducción Enzimática/efectos de los fármacos , Inmunohistoquímica , Hibridación in Situ , Hígado/efectos de los fármacos , Hígado/enzimología , Pulmón/efectos de los fármacos , Masculino , Datos de Secuencia Molecular , Sondas ARN , ARN Mensajero/análisis , ARN Mensajero/biosíntesis , Ratas , Ratas Sprague-Dawley , Esteroide Hidroxilasas/análisis , Esteroide Hidroxilasas/genética
16.
Infect Immun ; 62(7): 2893-900, 1994 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-7999145

RESUMEN

Bordetella pertussis expresses factors such as filamentous hemagglutinin, agglutinogens, pertactin, and pertussis toxin, which participate in bacterial adhesion; pertussis toxin, dermonecrotic toxin, lipopolysaccharide, and tracheal cytotoxin, which are responsible for toxic effects; and adenylate cyclase-hemolysin, which is required to initiate infection. By using a murine respiratory model, we showed that the RGD sequences of filamentous hemagglutinin and pertactin are important for bacterial persistence. However, mutants deficient in filamentous hemagglutinin and agglutinogens or in pertactin and the RGD sequence of filamentous hemagglutinin behaved as did wild-type B. pertussis, i.e., induced bronchopneumonia, alveolitis, and an influx of macrophages, lymphocytes, and polymorphonuclear leukocytes into bronchoalveolar lavage fluids. These results suggest that these adhesins are not involved in the induction of pulmonary lesions following infection. The intensity of inflammation was markedly reduced after infection with mutants deficient in either hemolytic activity or pertussis toxin expression, whereas a mutant devoid of adenylate cyclase activity behaved as did the avirulent mutant. Pertussis toxin and adenylate cyclase-hemolysin may act indirectly by altering immune cell functions and thus allowing other factors, such as filamentous hemagglutinin, agglutinogens, and pertactin, to trigger adhesion and lipopolysaccharide, dermonecrotic toxin, and tracheal cytotoxin to induce their toxic effects. However, it is possible that pertussis toxin is also responsible for the induction of some pulmonary alterations.


Asunto(s)
Adhesión Bacteriana/genética , Bordetella pertussis/genética , Bordetella pertussis/patogenicidad , Pulmón/microbiología , Factores de Virulencia de Bordetella , Tos Ferina/patología , Secuencia de Aminoácidos , Animales , Proteínas de la Membrana Bacteriana Externa/genética , Toxinas Bacterianas/genética , Líquido del Lavado Bronquioalveolar/citología , Moléculas de Adhesión Celular/genética , Modelos Animales de Enfermedad , Hemaglutininas/genética , Inflamación/etiología , Inflamación/patología , Pulmón/patología , Ratones , Datos de Secuencia Molecular , Oligopéptidos/genética , Alveolos Pulmonares/microbiología , Alveolos Pulmonares/patología , Virulencia/genética , Tos Ferina/etiología
17.
Braz J Med Biol Res ; 27(7): 1653-8, 1994 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-7874032

RESUMEN

Bronchi from guinea pigs actively sensitized to ovalbumin and boosted two weeks later display increased numbers of CD4+ T-lymphocytes and eosinophils. We have further investigated immunopathological changes in sensitized guinea pigs 2 or 24 h after antigenic challenge with ovalbumin. Lungs were resected, frozen and cryostat sections stained with monoclonal antibodies that recognize relevant guinea pig epitopes. Cyanide-resistant peroxidase activity was used to stain eosinophils. No further increase in T-lymphocytes or eosinophils was observed 2 h after challenge. At 24 h, a marked increase in EPO+ eosinophils was found, and this was accompanied by severe mucosal damage characterized by epithelial shedding and ulceration. The numbers of T-lymphocytes remained stable but a novel population of cells with the appearance of dendritic cells was seen in the bronchial wall. They were negative for macrophage markers but were strongly Class II positive. These findings suggest that antigenic challenge results in further recruitment of eosinophils, their activation and release of toxic substances to the epithelium. Furthermore, other cell types, possibly dendritic cells, are attracted to the bronchi and could play a role in maintaining allergic inflammation via antigen presentation.


Asunto(s)
Bronquios/inmunología , Hiperreactividad Bronquial/inmunología , Células Dendríticas/inmunología , Eosinófilos/inmunología , Linfocitos T/inmunología , Animales , Antígenos/inmunología , Bronquios/patología , Hiperreactividad Bronquial/patología , Cobayas , Ovalbúmina/administración & dosificación , Factores de Tiempo
18.
Braz. j. med. biol. res ; 27(7): 1653-1658, Jul. 1994.
Artículo en Inglés | LILACS | ID: lil-319779

RESUMEN

Bronchi from guinea pigs actively sensitized to ovalbumin and boosted two weeks later display increased numbers of CD4+ T-lymphocytes and eosinophils. We have further investigated immunopathological changes in sensitized guinea pigs 2 or 24 h after antigenic challenge with ovalbumin. Lungs were resected, frozen and cryostat sections stained with monoclonal antibodies that recognize relevant guinea pig epitopes. Cyanide-resistant peroxidase activity was used to stain eosinophils. No further increase in T-lymphocytes or eosinophils was observed 2 h after challenge. At 24 h, a marked increase in EPO+ eosinophils was found, and this was accompanied by severe mucosal damage characterized by epithelial shedding and ulceration. The numbers of T-lymphocytes remained stable but a novel population of cells with the appearance of dendritic cells was seen in the bronchial wall. They were negative for macrophage markers but were strongly Class II positive. These findings suggest that antigenic challenge results in further recruitment of eosinophils, their activation and release of toxic substances to the epithelium. Furthermore, other cell types, possibly dendritic cells, are attracted to the bronchi and could play a role in maintaining allergic inflammation via antigen presentation.


Asunto(s)
Animales , Cobayas , Bronquios , Células Dendríticas/inmunología , Eosinófilos/inmunología , Hiperreactividad Bronquial/inmunología , Linfocitos T , Antígenos/inmunología , Bronquios , Hiperreactividad Bronquial/patología , Ovalbúmina , Factores de Tiempo
19.
Am J Respir Cell Mol Biol ; 9(1): 44-53, 1993 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-8338676

RESUMEN

Isolated lungs from guinea pigs actively sensitized to ovalbumin and boosted 2 wk later display an enhanced bronchoconstriction and release larger amounts of secondary mediators as compared with lungs from nonimmunized animals when stimulated by platelet-activating factor or other agonists. We have investigated changes in T lymphocytes and eosinophils found in the bronchial wall of immunized and nonimmunized guinea pigs. The animals received two injections of 10 micrograms ovalbumin in Al(OH)3, at a 2-wk interval. Two studies were performed: (1) the animals were killed 7 days after the booster injection of antigen, (2) they were challenged with ovalbumin at this same day and killed after 2 or 24 h. Lungs were resected and frozen, and cryostat sections stained using monoclonal antibodies that recognize T cells, T cell subsets, or other relevant epitopes. Cyanide-resistant peroxidase activity was used to identify eosinophils. A large number of T cells, mainly of the CD4+ subset, and eosinophils were recruited into the bronchi 7 days after the booster injection of the antigen, compared with nonimmunized or nonboosted animals. In antigen-challenged animals, the numbers of T cells did not change but eosinophils were further increased in number at the 24 h time point. Also at this time point, a population of cells with a dendritic appearance was seen in the bronchial wall, which did not express macrophage markers but was strongly class II positive. Class II positivity was also noted in the bronchial epithelium and on many cells infiltrating the mucosa. These findings suggest that activated T cells and/or their products play an important role in the bronchopulmonary immunopathology associated with this model and possibly with the development of bronchial hyperreactivity.


Asunto(s)
Bronquios/patología , Hiperreactividad Bronquial/patología , Ovalbúmina/administración & dosificación , Vacunación , Animales , Antígenos/inmunología , Bronquios/inmunología , Hiperreactividad Bronquial/inmunología , Células Dendríticas , Eosinófilos/inmunología , Cobayas , Antígenos de Histocompatibilidad Clase II/inmunología , Inmunización Secundaria , Masculino , Fenotipo , Subgrupos de Linfocitos T/inmunología , Linfocitos T/inmunología
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