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1.
Int J Oral Maxillofac Surg ; 51(5): 659-664, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-34756661

RESUMEN

Orthognathic surgery aims to correct dentoskeletal and facial discrepancies. The expected benefits are functional, cosmetic, and psychological. In a previous publication, this group assessed the determinants of patient satisfaction to formulate the Northwick Park Orthognathic Questionnaire (NOQ). The aim of the present study was to validate this questionnaire. A total of 118 postoperative patients prospectively completed the NOQ, 30 of whom completed the questionnaire a second time. The mean completion rate was 87.6 ± 10%. Response reproducibility was high: 92% of patients gave identical responses (range 81-100%). The intra-class correlation coefficient (ICC) was 0.96 (0.96 ± 0.072). Average test-retest scores for each domain were as follows (range in parenthesis): reasons for treatment 93% (60-100%), preoperative experience 96% (81-100%), preparation for surgery 95% (81-100%), inpatient experience 89% (55-100%), post-discharge experience 83% (55-100%), benefits of treatment 92% (71-100%), overall patient education 91% (62-100%). Internal validity using Cronbach's alpha was 0.72 (standard deviation 0.23, range 0.5-1). The results confirm the consistency of responses and the reliability of the information collected with the NOQ. The NOQ is a novel questionnaire and a valid metric to quantify a patient's perception of their experience. Its adoption may aid in making targeted improvements to patient care.


Asunto(s)
Cirugía Ortognática , Cuidados Posteriores , Humanos , Alta del Paciente , Medición de Resultados Informados por el Paciente , Psicometría , Calidad de Vida , Reproducibilidad de los Resultados , Encuestas y Cuestionarios
2.
Nat Commun ; 9(1): 1051, 2018 03 13.
Artículo en Inglés | MEDLINE | ID: mdl-29535307

RESUMEN

There is an urgent need to develop vaccines against pathogenic bacteria. However, this is often hindered by antigenic diversity and difficulties encountered manufacturing membrane proteins. Here we show how to use structure-based design to develop chimeric antigens (ChAs) for subunit vaccines. ChAs are generated against serogroup B Neisseria meningitidis (MenB), the predominant cause of meningococcal disease in wealthy countries. MenB ChAs exploit factor H binding protein (fHbp) as a molecular scaffold to display the immunogenic VR2 epitope from the integral membrane protein PorA. Structural analyses demonstrate fHbp is correctly folded and the PorA VR2 epitope adopts an immunogenic conformation. In mice, immunisation with ChAs generates fHbp and PorA antibodies that recognise the antigens expressed by clinical MenB isolates; these antibody responses correlate with protection against meningococcal disease. Application of ChAs is therefore a potentially powerful approach to develop multivalent subunit vaccines, which can be tailored to circumvent pathogen diversity.


Asunto(s)
Anticuerpos Antibacterianos/inmunología , Antígenos Bacterianos/inmunología , Proteínas Bacterianas/inmunología , Neisseria meningitidis Serogrupo B/inmunología , Animales , Humanos , Vacunas Meningococicas/inmunología
3.
J Laryngol Otol ; 129(3): 283-7, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25797450

RESUMEN

OBJECTIVE: To present the first report of a giant frontal sinus osteoma treated by excision and single-stage reconstruction with custom-made titanium cranioplasty and left orbital roof prostheses. CASE REPORT: A 31-year-old man with a history of chronic frontal sinusitis presented with a deforming, painless, midline forehead swelling of 11 years' duration, which had been treated unsuccessfully in Nigeria. Differential diagnosis included both benign and malignant bony tumours. Computerised tomography revealed a giant bony frontal sinus tumour extending beyond the sinus roof and breaching the left orbit, consistent with fibrous dysplasia. Given the extent of the tumour, open craniectomy was performed for surgical extirpation. Histological analysis identified multiple osteomas. This surgical approach achieved excellent cosmesis, with no evidence of recurrence at 12-month follow up. CONCLUSION: Forehead swelling may pose diagnostic and management dilemmas for the ENT surgeon; however, effective management is facilitated by a multidisciplinary approach.


Asunto(s)
Displasia Fibrosa Ósea/diagnóstico , Seno Frontal/patología , Osteoma/diagnóstico , Adulto , Neoplasias Óseas/diagnóstico , Neoplasias Óseas/patología , Neoplasias Óseas/cirugía , Diagnóstico Diferencial , Displasia Fibrosa Ósea/patología , Displasia Fibrosa Ósea/cirugía , Seno Frontal/cirugía , Sinusitis Frontal/patología , Sinusitis Frontal/cirugía , Humanos , Masculino , Órbita/patología , Osteoma/patología , Osteoma/cirugía , Neoplasias de los Senos Paranasales/diagnóstico , Neoplasias de los Senos Paranasales/patología , Neoplasias de los Senos Paranasales/cirugía , Prótesis e Implantes , Procedimientos de Cirugía Plástica/métodos , Titanio , Tomografía Computarizada por Rayos X
4.
J Laryngol Otol ; 127(12): 1238-41, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24125173

RESUMEN

OBJECTIVE: We report the rare case of a 55-year-old woman with an asymptomatic left sphenoid sinus pseudomeningocele mimicking a mucocele. CASE REPORT: A 55-year-old woman was found to have an incidental mass in the left sphenoid sinus on computed tomography. Magnetic resonance imaging confirmed the presence of a mucocele. A left endoscopic sphenoidotomy was performed to drain the mucocele. Despite an anatomical puncture through a stenosed sphenoid ostium, alarmingly, the opening leaked cerebrospinal fluid. A dehiscent lateral wall was identified with a dural opening communicating with the sphenoid sinus. This was immediately repaired with a free nasal septal mucosal graft. Six months post-operatively, the patient remained free from cerebrospinal fluid leakage. CONCLUSION: Pseudomeningoceles are extremely rare in the absence of trauma or iatrogenic injury. Surgeons should be alert to their presence as they can mimic a unilateral mucocele or nasal polyp. Endoscopic management lends itself to a single-stage repair.


Asunto(s)
Mucocele/diagnóstico , Cirugía Endoscópica por Orificios Naturales , Seno Esfenoidal/anomalías , Seno Esfenoidal/diagnóstico por imagen , Medios de Contraste , Diagnóstico Diferencial , Drenaje/efectos adversos , Drenaje/métodos , Femenino , Humanos , Hallazgos Incidentales , Imagen por Resonancia Magnética , Persona de Mediana Edad , Mucocele/diagnóstico por imagen , Mucocele/cirugía , Cirugía Endoscópica por Orificios Naturales/métodos , Seno Esfenoidal/cirugía , Tomografía Computarizada por Rayos X , Resultado del Tratamiento
5.
J Laryngol Otol ; 126(9): 966-9, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22892225

RESUMEN

OBJECTIVE: We report a case of rhabdomyosarcoma of the trachea in a 14-month-old child, and we present the first reported use of proton beam therapy for this tumour. CASE REPORT: A 14-month-old girl presented acutely with a seven-day history of biphasic stridor. Emergency endoscopic debulking of a posterior tracheal mass was undertaken. Histological examination revealed an embryonal rhabdomyosarcoma with anaplasia. Multimodality therapy with surgery and chemotherapy was administered in the UK, and proton beam therapy in the USA. CONCLUSION: Only three cases of rhabdomyosarcoma of the trachea have previously been reported in the world literature. This is the first reported case of treatment of this tumour with proton beam therapy. Compared with conventional radiotherapy, proton beam therapy may confer improved long-term outcome in children, with benefits including reduced irradiation of the spinal cord.


Asunto(s)
Obstrucción de las Vías Aéreas/diagnóstico , Terapia de Protones , Rabdomiosarcoma Embrionario/radioterapia , Neoplasias de la Tráquea/radioterapia , Adolescente , Obstrucción de las Vías Aéreas/etiología , Anaplasia , Niño , Terapia Combinada , Diagnóstico Diferencial , Endoscopía/métodos , Femenino , Humanos , Lactante , Imagen por Resonancia Magnética , Masculino , Ruidos Respiratorios/etiología , Rabdomiosarcoma Embrionario/diagnóstico , Rabdomiosarcoma Embrionario/patología , Neoplasias de la Tráquea/diagnóstico , Neoplasias de la Tráquea/patología , Resultado del Tratamiento
6.
Br J Pharmacol ; 153 Suppl 1: S283-97, 2008 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-18037926

RESUMEN

The effects of nicotine on dopamine transmission from mesostriatal dopamine neurons are central to its reinforcing properties. Only recently however, has the influence of presynaptic nicotinic receptors (nAChRs) on dopaminergic axon terminals within striatum begun to be understood. Here, rather than simply enhancing (or inhibiting) dopamine release, nAChRs perform the role of a presynaptic filter, whose influence on dopamine release probability depends on presynaptic activity in dopaminergic as well as cholinergic neurons. Both mesostriatal dopaminergic neurons and striatal cholinergic interneurons play key roles in motivational and sensorimotor processing by the basal ganglia. Moreover, it appears that the striatal influence of dopamine and ACh cannot be fully appreciated without an understanding of their reciprocal interactions. We will review the powerful filtering by nAChRs of striatal dopamine release and discuss its dependence on activity in dopaminergic and cholinergic neurons. We will also review how nicotine, acting via nAChR desensitization, promotes the sensitivity of dopamine synapses to activity. This filtering action might provide a mechanism through which nicotine promotes how burst activity in dopamine neurons facilitates goal-directed behaviour and reinforcement processing. More generally, it indicates that we should not restrict our view of presynaptic nAChRs to simply enhancing neurotransmitter release. We will also summarize current understanding of the forms and functions of the diverse nAChRs purported to exist on dopaminergic axons. A greater understanding of nAChR form and function is imperative to guide the design of ligands with subtype-selective efficacy for improved therapeutic interventions in nicotine addiction as well as Parkinson's disease.


Asunto(s)
Dopamina/fisiología , Neostriado/fisiología , Sistema Nervioso Parasimpático/fisiología , Receptores Nicotínicos/fisiología , Receptores Presinapticos/fisiología , Transmisión Sináptica/fisiología , Animales , Humanos , Terminales Presinápticos/fisiología , Receptor Cross-Talk/fisiología
7.
Neuropharmacology ; 44(4): 503-15, 2003 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-12646287

RESUMEN

Cytisine (cy) is a potent and competitive partial agonist at alpha4 subunit-containing nicotinic acetylcholine (nACh) receptors while at homomeric alpha7-nACh receptors it behaves as a full agonist with a relatively lower potency. In the present study, we assessed the effects of bromination or iodination of the pyridone ring of cy and N-methylcytisine (N-Me-cy) on the effects of these compounds on recombinant human (h) alpha7, halpha4beta2 and halpha4beta4 nACh receptors expressed in clonal cell lines and Xenopus oocytes. Halogenation at C(3) of cy or N-Me-cy usually brings about a marked increase in both affinity and efficacy at halpha7, halpha4beta2 and halpha4beta4 nACh, the extent of which depends on whether the halogen is bromine or iodine, and upon receptor subtype. The effects of halogenation at C(5) are strongly influenced by the specific halogen substituent so that bromination causes a decrease in both affinity and efficacy while iodination decreases affinity but its effects on efficacy range from a decrease (halpha7, halpha4beta4 nACh receptors) to a marked increase (halpha4beta2 nACh receptors). Based on these findings, which differ from those showing that neither the affinity nor efficacy of nicotine, 3-(2-azetidinylmethoxy)-pyridine or epibatidine are greatly affected by halogenation, dehalogenation or halogen exchange at equivalent positions, we suggest that cy, N-Me-cy and their halo-isosteres bind to neuronal nACh receptors in a different orientation allowing the halogen atom to interact with a hydrophobic halogen-accepting region within the predominantly hydrophobic agonist-binding pocket of the receptors.


Asunto(s)
Alcaloides/farmacología , Agonistas Nicotínicos/farmacología , Receptores Nicotínicos/efectos de los fármacos , Alcaloides/química , Animales , Azocinas , Bromo/química , Línea Celular , Humanos , Yodo/química , Agonistas Nicotínicos/química , Técnicas de Placa-Clamp , Quinolizinas , Ensayo de Unión Radioligante , Receptores Nicotínicos/metabolismo , Receptores Nicotínicos/fisiología , Proteínas Recombinantes/metabolismo , Relación Estructura-Actividad , Xenopus laevis
8.
FEMS Microbiol Lett ; 202(2): 171-6, 2001 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-11520610

RESUMEN

Two Csp proteins (CspA and CspD) were fused to the green fluorescent protein GFP and expressed from their natural promoters or from an inducible promoter. Fluorescence microscopy and computerized image analysis indicate that in Escherichia coli growing at 37 degrees C CspD localizes in the nucleoid like the control H-NS while CspA occupies a polar position away from the nucleoid. Following cold shock CspA maintains its location, while CspD is not sufficiently expressed to permit its localization. The different localization of CspA and CspD indicates that these proteins play different roles in the cell in spite of their extensive structural similarity.


Asunto(s)
Proteínas Bacterianas/biosíntesis , Escherichia coli/metabolismo , Factores de Transcripción/biosíntesis , Proteínas Bacterianas/análisis , Western Blotting , Nucléolo Celular , Frío , Proteínas Fluorescentes Verdes , Proteínas Luminiscentes , Microscopía Fluorescente , Factores de Transcripción/análisis
9.
Biochimie ; 83(2): 269-75, 2001 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11278078

RESUMEN

The condensation of DNA in bacterial nucleoids during cell cycle is a complex and dynamic process. Proteins displaying the physico-chemical properties of histones are known to contribute to this process. During a search for B. subtilis nucleoid associated proteins, HBsu and L24 were identified as the most abundant proteins in nucleoid containing fractions. Purified L24 binds and condenses DNA in vitro. In this paper we describe immunofluorescence studies that demonstrated that L24 is located at the poles of the nucleoids in exponentially growing cells. In contrast, the protein is dispersed in the cytoplasm during stationary phase. Moreover, overexpression of the rplX gene encoding L24 disrupts nucleoid segregation and positioning.


Asunto(s)
Bacillus subtilis/genética , Segregación Cromosómica , ADN Bacteriano/metabolismo , Proteínas Ribosómicas/metabolismo , División Celular , Cromosomas Bacterianos , Hibridación Fluorescente in Situ , Microscopía Fluorescente , Plásmidos , ARN Ribosómico/química , Proteínas Ribosómicas/aislamiento & purificación
10.
J Bacteriol ; 182(16): 4414-24, 2000 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10913073

RESUMEN

The lrpC gene was identified during the Bacillus subtilis genome sequencing project. Previous experiments suggested that LrpC has a role in sporulation and in the regulation of amino acid metabolism and that it shares features with Escherichia coli Lrp, a transcription regulator (C. Beloin, S. Ayora, R. Exley, L. Hirschbein, N. Ogasawara, Y. Kasahara, J. C. Alonso, and F. Le Hégarat, Mol. Gen. Genet. 256:63-71, 1997). To characterize the interactions of LrpC with DNA, the protein was overproduced and purified. We show that LrpC binds to multiple sites in the upstream region of its own gene with a stronger affinity for a region encompassing P1, one of the putative promoters identified (P1 and P2). By analyzing lrpC-lacZ transcriptional fusions, we demonstrated that P1 is the major in vivo promoter and that, unlike many members of the lrp/asnC family, lrpC is not negatively autoregulated but rather slightly positively autoregulated. Production of LrpC in vivo is low in both rich and minimal media (50 to 300 LrpC molecules per cell). In rich medium, the cellular LrpC content is six- to sevenfold lower during the exponentional phase than during the stationary growth phase. Possible determinants and the biological significance of the regulation of lrpC expression are discussed.


Asunto(s)
Bacillus subtilis/genética , Bacillus subtilis/metabolismo , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Regulación Bacteriana de la Expresión Génica , Regiones Promotoras Genéticas , Factores de Transcripción , Secuencia de Aminoácidos , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Secuencia de Bases , Sitios de Unión , Clonación Molecular , Cartilla de ADN , ADN Bacteriano/química , ADN Bacteriano/genética , Escherichia coli/genética , Proteínas de Escherichia coli , Proteína Reguladora de Respuesta a la Leucina , Datos de Secuencia Molecular , Conformación de Ácido Nucleico , Proteínas Recombinantes de Fusión/metabolismo
11.
Thromb Haemost ; 81(1): 96-103, 1999 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-10348718

RESUMEN

Plasminogen activator inhibitor 2 (PAI-2) is a major product of activated human monocytes. Here we show that monocytes inhibited u-PA- but not t-PA-mediated fibrinolysis, by secreting PAI-2 into an overlying fibrin clot. Extracts of arterial and venous human thrombi were found to contain active PAI-2. PAI-2 was cross-linked to fibrin in a reaction catalyzed by two major transglutaminases (TG), tissue TG and factor XIII. The activity of PAI-2 was not affected by such cross-linking. Cross-linking of PAI-2 to fibrin was inhibited by Tridegin, a specific inhibitor of TG, and also by EDTA and iodoacetamide. The use of competitive peptides mimicking the loop between helices C and D of PAI-2 identified Gln 83 and 86 as residues important in cross-linking. This study defines a mechanism by which PAI-2 is localized to fibrin, where it acts as an effective inhibitor of u-PA-mediated fibrinolysis.


Asunto(s)
Fibrina/metabolismo , Fibrinólisis , Monocitos/metabolismo , Inhibidor 2 de Activador Plasminogénico/metabolismo , Activador de Plasminógeno de Tipo Uroquinasa/metabolismo , Células Cultivadas , Reactivos de Enlaces Cruzados , Fibrinólisis/efectos de los fármacos , Humanos , Péptidos/metabolismo , Inhibidor 2 de Activador Plasminogénico/farmacología
12.
Mol Gen Genet ; 256(1): 63-71, 1997 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-9341680

RESUMEN

In the course of the Bacillus subtilis genome sequencing project, we identified an open reading frame encoding a putative 16.4 kDa protein. This protein shows, respectively, 34% and 25% identity with the Escherichia coli regulatory proteins Lrp and AsnC. Phylogenetic analysis suggests that it represents a new group in the AsnC-Lrp family. Sequence comparisons, as well as immunodetection experiments, lead to the conclusion that the product of this B. subtilis lrp-like-gene is a bona fide Lrp protein-the first one to be detected in gram-positive bacteria. When expressed in E. coli, the B. subtilis Lrp-like protein is able to repress, by about two-fold, the expression of the ilvIH operon which is normally regulated by E. coli Lrp, indicating functional similarity in their regulatory targets. Vegetative growth of a B. subtilis lrp-like mutant is not affected in rich medium. However, the lrp-like mutation causes a transitory inhibition of growth in minimal medium in the presence of valine and isoleucine, which is relieved by leucine. This points to a possible role in regulation of amino acid metabolism. In addition, sporogenesis occurs earlier in the lrp-like mutant than in the reference strain, implying that the B subtilis Lrp-like protein plays a role in the growth phase transition.


Asunto(s)
Bacillus subtilis/genética , Genes Bacterianos , Factores de Transcripción , Secuencia de Aminoácidos , Bacillus subtilis/química , Bacillus subtilis/crecimiento & desarrollo , Proteínas Bacterianas/química , Proteínas Bacterianas/genética , Proteínas Bacterianas/fisiología , Secuencia de Bases , Southern Blotting , Western Blotting , Clonación Molecular , Proteínas de Unión al ADN/química , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/fisiología , Escherichia coli/química , Escherichia coli/genética , Proteínas de Escherichia coli , Regulación Bacteriana de la Expresión Génica , Calor , Operón Lac/genética , Proteína Reguladora de Respuesta a la Leucina , Datos de Secuencia Molecular , Mutagénesis Insercional , Sistemas de Lectura Abierta , Operón , Filogenia , Análisis de Secuencia de ADN , Esporas Bacterianas/fisiología , beta-Galactosidasa/genética , beta-Galactosidasa/metabolismo
13.
Proc Natl Acad Sci U S A ; 84(18): 6467-70, 1987 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-3114750

RESUMEN

Treatment of the Daudi Burkitt lymphoma-derived cell line with human interferon alpha, which inhibits cell proliferation in this system, induces differentiation of these B-lymphoid cells into cells with a plasmacytoid phenotype. This differentiation, quantified by the appearance of surface antigens characteristic of mature plasma cells, is impaired by addition to the culture medium of the ADP-ribosyltransferase (ADPRT; EC 2.4.2.30) inhibitors 3-methoxybenzamide or 3-aminobenzamide. These agents also protect the cells against the inhibition of proliferation induced by low doses of interferon alpha. In contrast, the large inhibition of thymidine incorporation into DNA caused by interferon treatment is not affected by the ADPRT inhibitors. The phorbol ester phorbol 12-tetradecanoate 13-acetate induces the same plasma cell surface antigens that are induced by interferon treatment, and this effect is also impaired by the ADPRT inhibitors. These results suggest that interferons and phorbol esters share a mechanism of action that requires ADPRT activity. Protection of the cells against the antiproliferative effect of interferons by the ADPRT inhibitors suggests that growth inhibition may be a consequence of cell differentiation. In contrast, the inhibition of thymidine incorporation alone is not sufficient for the cessation of cell proliferation and is not a true reflection of the rate of DNA synthesis.


Asunto(s)
Antígenos de Superficie/análisis , Linfocitos B/inmunología , Inhibidores de Poli(ADP-Ribosa) Polimerasas , Linfocitos B/citología , Benzamidas/farmacología , Diferenciación Celular/efectos de los fármacos , Línea Celular , ADN/biosíntesis , Humanos , Interferón Tipo I/farmacología , Acetato de Tetradecanoilforbol/farmacología
14.
Int J Cancer ; 40(1): 53-7, 1987 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-2439466

RESUMEN

Treatment of Daudi B-lymphoblastoid cells with low concentrations of either natural or recombinant human alpha-interferons inhibits cell proliferation and modulates the expression of a number of cell-surface antigens. Using a panel of monoclonal antibodies (MAbs) identifying determinants expressed at the surface of normal plasma cells, and polyclonal antibodies against surface and cytoplasmic immunoglobulin, we have found that growth inhibition is accompanied by plasmacytoid differentiation. Assays of growth stimulation of heterologous cells indicate that the culture medium from interferon-treated Daudi cells contains substantially more B-cell growth factor activity than that from control cells. However, the interferon-treated cells exhibit an impaired ability to respond to both these autocrine factors and exogenous factors produced by another Burkitt lymphoma line. These findings show that, in the case of Daudi cells, growth inhibition by interferons is closely associated with both terminal differentiation and a refractoriness to growth factors. In this system IFN-alpha may therefore be considered to be a B-cell differentiation factor, suggesting a possible basis for the anti-proliferative effects observed with certain human B-cell malignancies.


Asunto(s)
Linfoma de Burkitt/patología , Sustancias de Crecimiento/farmacología , Interferones/farmacología , Anticuerpos Monoclonales , Antígenos de Superficie/biosíntesis , Linfocitos B/análisis , Diferenciación Celular/efectos de los fármacos , División Celular/efectos de los fármacos , Humanos
15.
Pharmacol Biochem Behav ; 25(5): 989-93, 1986 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-3786371

RESUMEN

Opiate naive rats received 24 hours of continuous subcutaneous infusion of 0.67 mg/kg/hr naloxone via osmotic minipump. As in previous studies, this induced an opiate-abstinence-like syndrome of significantly increased oxygen consumption and behavioral signs (wet-dog shakes, abdominal writhes, etc.). Clonidine, which selectively reduces central noradrenergic activity, has been shown to reverse opiate abstinence syndrome. Subcutaneous injection of 0.033 and 0.01 mg/kg clonidine totally reversed the abstinence-like behaviors and respiratory activity induced by naloxone infusion. This constitutes an additional point of similarity between opiate abstinence syndrome and the "endorphin blockade syndrome" or withdrawal from endogenous opioids resulting from chronic naloxone treatment. It is consistent with the hypothesis that hyperactivity of central noradrenergic mechanisms may contribute to both phenomena.


Asunto(s)
Conducta Animal/efectos de los fármacos , Clonidina/farmacología , Naloxona/antagonistas & inhibidores , Consumo de Oxígeno/efectos de los fármacos , Animales , Masculino , Naloxona/administración & dosificación , Naloxona/farmacología , Ratas , Ratas Endogámicas
16.
Med Oncol Tumor Pharmacother ; 3(3-4): 269-73, 1986.
Artículo en Inglés | MEDLINE | ID: mdl-3027466

RESUMEN

The autocrine growth profile of human B lymphocytes transformed with Epstein-Barr virus (EBV) was found to comprise three distinct components: a B-cell growth factor (BCGF); an interleukin-1 (IL-1)-like activity; an activity requiring cell-to-cell contact for its action. Observations on the inhibition of the EBV-carrying Daudi lymphoma line by alpha-interferon indicated that loss of response to these autostimulatory factors was underlying growth cessation. Furthermore, a putative receptor for BCGF was found to be down-regulated on B cells stimulated with non-transforming mitogens but constitutively expressed following EBV-transformation. Taken together with recent evidence that normal B cells produce autostimulatory factors, these findings suggest that the special feature of autocrine growth by EBV-immortalized cells is a maintenance of what should normally be a transient phenotype, possibly through deregulation of receptor expression. This hypothesis is discussed.


Asunto(s)
Linfocitos B/microbiología , Transformación Celular Viral , Herpesvirus Humano 4 , Linfocitos B/citología , Comunicación Celular , División Celular , Sustancias de Crecimiento/análisis , Humanos , Interleucina-1/análisis , Interleucina-4 , Cinética , Linfocinas/análisis , Peso Molecular , Receptores de Interleucina-4 , Receptores Mitogénicos/análisis
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