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1.
Encephale ; 49(2): 152-157, 2023 Apr.
Artículo en Francés | MEDLINE | ID: mdl-36253182

RESUMEN

Psychiatric emergency units (UUP) are nowadays important gateways to healthcare. Whether integrated into general emergency departments or not, these units have very heterogeneous resources and organisations which are not always in line with a populations' needs. The increasing activity of emergency departments in recent years and the recurrent psychiatric bed shortages have shed light upon the weaknesses of this key link in the mental healthcare process. The Seine-Saint-Denis is a department of France located in the Grand Paris metropolis in the Île-de-France region. Ranked third in terms of population size in France, it is marked by social precariousness. With regard to mental health, it has one of the lowest rates of psychiatric beds per capita in France. A great deal of thought has been ongoing for five years on how best to upgrade the offer of unscheduled psychiatric care, particularly the management of emergencies. The growing imbalance between demand and supply depending on living areas urges a rapid equalization of resources. This operation requires an accurate activity characterization, allowing more effective organizations and adequate resource allocation. We sought to characterize the activity of psychiatric emergencies by selecting quantitative and qualitative indicators by means of a consensus method, the Delphi Method, which consists of iterative questioning of an expert group. We first submitted 36 potential criteria to twenty-five experts. Twenty obtained a weak to a strong consensus. Seventeen were then selected as potentially useful for activity characterization. In a second time, we tested the consensus on selected indicators by interviewing a panel of 19 experts. A strong consensus was found on four criteria: "Number of visits for psychiatric advice>2000/year", "Number of emergency room visits>40,000/year", "Density of adult hospital beds<150 per 100,000 inhabitants", "Passage rate for homeless patients and/or outside the sector>10%". Using these criteria in the classification of UUPs would test their validity and provide a potentially helpful tool for improving organizations and resource allocation.


Asunto(s)
Urgencias Médicas , Servicio de Urgencia en Hospital , Adulto , Humanos , Técnica Delphi , Francia/epidemiología , Salud Mental
2.
Epidemiol Infect ; 144(16): 3365-3375, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27535719

RESUMEN

Hepatitis B virus (HBV) vaccination has been part of the Expanded Programme of Immunization (EPI) in Tunisia since 1995. The aim of this study was to evaluate, for the first time, the impact of mass vaccination in Tunisia 17 years after this programme was implemented, and in parallel, assess the long-term persistence of anti-HBs antibody in the vaccinated Tunisian population. A total of 1422 students were recruited (703 vaccinated, 719 non-vaccinated). HBV seromarkers were checked. None of the students from either group had positive HBsAg. The overall prevalence of anti-HBc was 0·8%. A Significantly higher prevalence of anti-HBc was noted in unvaccinated students than in vaccinated (1·4% vs. 0·3%, P = 0·02). The overall seroprotection rate (anti-HBs titre ⩾10 mIU/ml) was 68·9% in vaccinated subjects. Seroprotection rates and geometric mean titres decreased significantly with increasing age, reflecting waning anti-HBs titre over time. No significant difference was detected between seroprotection rates and gender or students' area of origin. Incomplete vaccination was the only factor associated with an anti-HBs titre <10 mIU/ml. This study demonstrates the excellent efficacy of the HBV vaccination programme in Tunisia 17 years after its launch. However, a significant decline of anti-HBs seroprotection has been observed in ⩾15-year-old adolescents which places them at risk of infection. Additional studies are needed in hyperendemic regions in Tunisia.

4.
J Fr Ophtalmol ; 2023 Oct 06.
Artículo en Inglés | MEDLINE | ID: mdl-37806934

RESUMEN

OBJECTIVE: The goal of this clinical case is to report a case of ophthalmic zoster in a five-year-old boy and to insist on the relevance of early antiviral treatment (aciclovir) so as to minimize corneal affection and preserve visual function. OBSERVATION: We report the case of a five-year-old boy of preschool age with no notable pathological history who came for consultation with a painful eruption affecting the forehead, the upper eyelid, the nose. The clinical examination showed many erythematous vesicles affecting the left hemi-face. The diagnosis of ophthalmic zoster has been retained. Minimum biological laboratory assessment is normal. The treatment was local antiseptic and systemic aciclovir with high dose for ten days. The evolution was favorable. Zoster is rare in children. The ophthalmic form is exceptional. The diagnosis is clinical and should mention some bladdery lesions grouped in bunches with a disposition which follows a metamere. It can be responsible for serious ocular complications. CONCLUSION: The particularity of our observation is the presence of zoster in an immunocompetent child and the ophthalmic localization, that remains exceptional in children.

5.
Arch Razi Inst ; 78(1): 205-211, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-37312711

RESUMEN

The genus Ziziphora belongs to medicinal plants. It is often used as a stomach tonic, carminative, antimicrobial, and expectorant; the extracted essential oils can be used as a second line of defence against pathogens. This study aimed to determine the antioxidant activity of essential oils of Z. clinopodioides as well as antibacterial activity against foodborne pathogens (Bacillus sp., Escherichia coli, Staphylococcus aureus and Pseudomonas sp.). The antibacterial activity of Z. clinopodioides essential oil was determined using the microdilution (M.D.) method in the nutritional broth medium and the agar disk diffusion assay. The result demonstrated that essential oil exhibit solid antibacterial properties against both gram-positive and gram-negative bacteria. Sequentially regarding MIC and MBC values, Escherichia coli was a higher level of resistance to the essential oil compared to Bacillus sp. Our findings suggested that the essential oil of Z. clinopodioides could be used as an antibacterial agent. The total antioxidant capacity of Z. clinopodioides leaves was assessed as ascorbic acid equivalents per gram of the leaves essential oil extract. The total antioxidant capacity was determined using ascorbic acid (y=0.1185x + 49.508, R2=0.3877). While the result of Z. clinopodioides was (y=0.1372x + 40.032, R2=0.4503).


Asunto(s)
Lamiaceae , Aceites Volátiles , Animales , Antioxidantes/farmacología , Antibacterianos/farmacología , Bacterias Gramnegativas , Bacterias Grampositivas , Ácido Ascórbico , Escherichia coli , Aceites Volátiles/farmacología
6.
Ann Cardiol Angeiol (Paris) ; 71(2): 112-114, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32829892

RESUMEN

The pulmonary alveolocapillary dysplasia (ACD) with pulmonary vein misalignment (PVM) is a rare condition characterized by a congenital anomaly of the development of the pulmonary parenchyma. We present a case of an 8-month-old infant who died quickly from acute respiratory failure complicating an unknown ACD. We also describe its epidemiological characteristics in infants and we discuss the diagnosis's difficulties. In this case, a pulmonary arterial hypertension was decompensated by an infection. A medico-legal autopsy was performed. As for the Histological examination, it showed the features of ACD/PVM.


Asunto(s)
Síndrome de Circulación Fetal Persistente , Venas Pulmonares , Humanos , Lactante , Recién Nacido , Diagnóstico Erróneo , Síndrome de Circulación Fetal Persistente/diagnóstico , Síndrome de Circulación Fetal Persistente/patología , Alveolos Pulmonares/anomalías , Alveolos Pulmonares/irrigación sanguínea , Alveolos Pulmonares/patología , Venas Pulmonares/anomalías , Venas Pulmonares/patología
7.
J Exp Med ; 181(1): 21-31, 1995 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-7807003

RESUMEN

The barrier function of blood vessels is though to be regulated at least in part by endothelium. This concept is supported by the dramatic loss of barrier function occurring in the hyperacute rejection of vascularized grafts mediated by anti-endothelial cell (EC) antibodies and complement. In this process, the endothelium is not destroyed but instead loses the ability to retain blood cells and plasma proteins within capillaries. The noncytotoxic mechanism that allows this change in EC function has been unknown. Here we report that within 10 to 20 min of exposure to human xenoreactive natural antibodies and complement, porcine EC undergo alterations in cell shape and in the cytoskeleton that disrupt monolayer integrity and lead to formation of intercellular gaps. Gap formation is not associated with cell death but requires the complement complex C5b67. The gaps induced by anti-EC antibodies and complement are transient; gap closure requires formation of C5b-9 complexes on the cells and the rate of recovery depends on the release of cellular products into the medium. Preincubation of EC with dibutyryl cAMP (0.5 mM) prevents gap formation and disruption of the cytoskeleton caused by antibodies and complement. These results provide evidence that the integrity of endothelium is regulated by components of the complement system and suggest a mechanism that may explain the prominent loss of endothelial integrity seen in humoral immune responses.


Asunto(s)
Anticuerpos/inmunología , Proteínas del Sistema Complemento/farmacología , Endotelio Vascular/citología , Animales , Reacciones Antígeno-Anticuerpo , Supervivencia Celular , Activación de Complemento , AMP Cíclico/fisiología , Citoesqueleto/ultraestructura , Endotelio Vascular/inmunología , Humanos , Técnicas In Vitro , Uniones Intercelulares/ultraestructura , Permeabilidad , Porcinos , Factores de Tiempo
8.
J Exp Med ; 182(6): 1807-14, 1995 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-7500026

RESUMEN

Inflammation and immunity may be associated with endothelial cell (EC) injury and thrombus formation. We explored the mechanisms through which a humoral immune response directed against the endothelium might promote coagulation. Using the interaction of anti-EC antibodies and complement (C) with cultured EC as a model, we studied the expression and function of tissue factor, a cofactor for factor VIIa-mediated conversion of factor X to Xa. Exposure of EC to anti-EC antibodies and C in sublytic amounts stimulated the synthesis of tissue factor over a period of 16-42 h. Cell surface expression of tissue factor activity required activation of C and assembly of the membrane attack complex, because expression was inhibited by soluble CR1 and was not detected in the absence of C8. Elaboration of tissue factor messenger RNA was observed over a period of 8-30 h and required protein synthesis. Expression of tissue factor was not a direct consequence of the action of C on the EC but was a secondary response that required as an intermediate step the release of interleukin 1 alpha, an early product of the EC response to C activation. These findings suggest that, after the assembly of membrane attack complex on EC, the production of tissue factor and initiation of coagulation in a blood vessel depend on the production of interleukin 1 alpha and on its availability to stimulate affected EC.


Asunto(s)
Proteínas del Sistema Complemento/metabolismo , Endotelio Vascular/metabolismo , Tromboplastina/metabolismo , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Células Cultivadas , Cicloheximida/farmacología , Cartilla de ADN/química , Expresión Génica , Interleucina-1/metabolismo , Datos de Secuencia Molecular , Inhibidores de la Síntesis de la Proteína/farmacología , ARN Mensajero/genética , Porcinos , Tromboplastina/genética
9.
Ann Cardiol Angeiol (Paris) ; 69(2): 67-73, 2020 Apr.
Artículo en Francés | MEDLINE | ID: mdl-32222285

RESUMEN

Sudden cardiac death in young is seen as a dramatic phenomenon requiring knowledge of its impact. We aim to study the epidemiological characteristics of sudden cardiac ischemic death in young, and to discuss his involvement in the occurrence of death. We performed a retrospective cohort study using autopsy data from the department of forensic medicine of the University Hospital of Fattouma Bourguiba, Monastir-Tunisia. A review of all autopsies performed during 23 years was done. In each case, clinical information and circumstances of death were obtained. We have included all sudden death in persons aged between 1 year and 35 years for the male and from one year to 45 years for female. We collected 312 cases of sudden death during the studied period. The collected data were processed using SPSS 20. The significance level was set at 0.05. Thirty-two cases of cardiac ischemic sudden death have been collected. Myocardial infarction was the second cause of sudden death in young patients. There was a male predominance. The most affected subjects were aged between 25-45 years. The death occurred more frequently at rest. Coronary artery disease has been discovered in twenty-four cases (75%). The myocardial infarction occurred on healthy coronary arteries in eight cases. An anomalous course of coronary arteries, in particular myocardial bridging, was found in eight cases (25%). Toxicological screening was negative in all cases. Identifying epidemiological characteristics of sudden cardiac ischemic death in this population is important for guiding approaches to prevention that must be based on dietary hygienic measures and the control of cardiovascular risk factors.


Asunto(s)
Muerte Súbita Cardíaca/epidemiología , Infarto del Miocardio/mortalidad , Adolescente , Adulto , Distribución por Edad , Factores de Edad , Cardiomegalia/complicaciones , Cardiomegalia/mortalidad , Causas de Muerte , Niño , Preescolar , Enfermedad Coronaria/complicaciones , Enfermedad Coronaria/mortalidad , Muerte Súbita Cardíaca/etiología , Femenino , Humanos , Lactante , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Distribución por Sexo , Factores Sexuales , Túnez/epidemiología , Adulto Joven
10.
Int J Surg Case Rep ; 65: 48-51, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31689627

RESUMEN

INTRODUCTION: Ballistic traumatology of the shoulder joint is uncommon. Usually, it is associated to comminuted fractures of the upper humerus. Total shoulder arthroplasty has been proposed to restore a good function. The indication of resurfacing hemi arthroplasty still controversial and is not commonly reported after ballistic traumatology. PRESENTATION OF CASE: We report the case of a 26-year-old soldier victim of a gunshot of the left shoulder entailing a comminuted complex fracture of the upper extremity of the humerus. After shoulder immobilization of 3 months joint mobility was very limited. Radiographs showed bone malunion with a total loss of the hemispherical form of the humeral head. Patient has undergone a resurfacing hemi arthroplasty. Surgery outcome was good. At five years of follow-up, there were no major functional complaints. Clinical and radiological result was satisfactory with a good shoulder mobility. DISCUSSION: Shoulder arthroplasty provided good functional outcome in case of post fracture sequelae. Difficulty was to choose between total arthroplasty and hemi arthroplasty. In young and active patients, authors disapproved total arthroplasty in post traumatic gleno-humeral arthrosis to prevent revision difficulties especially after glenoid erosion. CONCLUSION: Although follow-up still be limited, the indication of shoulder hemi arthroplasty was appropriate regarding functional outcome and patient satisfaction. Further clinical and radiological supervision still necessary to detect glenoid erosion.

11.
J Clin Invest ; 100(5): 1150-8, 1997 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-9276732

RESUMEN

Lipid inflammatory mediators are thought to play a critical role in the pathogenesis of vascular injury. Among the events which might cause the synthesis of eicosanoids in blood vessels is activation of the complement. To evaluate how complement might influence eicosanoid metabolism, we investigated endothelial cells exposed to xenoreactive antibodies and complement, as might occur in rejecting xenografts where severe vascular injury is a typical feature. While resting porcine aortic endothelial cells released only prostaglandin (PG) I2, endothelial cells stimulated with xenoreactive antibodies and complement released PGE2 and thromboxane A2 (TXA2), in addition to increased amounts of PGI2. This alteration in eicosanoid metabolism was associated with induction of cyclooxygenase (Cox)-2 and thromboxane synthase, but not Cox-1. Unlike results seen in other systems, the upregulation of Cox-2 and the subsequent release of eicosanoids by endothelial cells was not directly induced by complement but rather required production of IL-1alpha, which acted on endothelial cells as an autocrine factor. Since eicosanoids have a potent effect on inflammation, vascular tone and platelet aggregation, we postulated that the abnormalities in eicosanoid release induced by xenoreactive antibodies and complement might provide one explanation for the vascular injury, focal ischemia, and thrombosis observed in acute vascular rejection and other vasculitides mediated by complement.


Asunto(s)
Eicosanoides/metabolismo , Endotelio Vascular/metabolismo , Isoenzimas/fisiología , Prostaglandina-Endoperóxido Sintasas/fisiología , Trasplante Heterólogo/inmunología , Animales , Células Cultivadas , Ciclooxigenasa 2 , Rechazo de Injerto , Interleucina-1/fisiología , Isoenzimas/análisis , Prostaglandina-Endoperóxido Sintasas/análisis , ARN Mensajero/análisis , Porcinos , Tromboxano-A Sintasa/análisis
12.
Surg Endosc ; 21(12): 2193-8, 2007 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-17522933

RESUMEN

INTRODUCTION: This study was undertaken to determine if the body position in which gastroesophageal reflux occurs before fundoplication--i.e., pattern of reflux--affects symptoms before or after laparoscopic Nissen fundoplication. METHODS: A total of 417 patients with gastroesophageal reflux disease (GERD) underwent pH studies, and the severity of reflux in the upright and supine positions was determined. The percent time with pH less than 4 was used to assign patients to one of four groups: upright reflux (pH < 4 more than 8.3% of time in upright position, n = 80), supine reflux (pH < 4 more than 3.5% of time in supine position, n = 73), bipositional reflux (both supine and upright reflux, n = 163), or neither (n = 101). Before and after laparoscopic Nissen fundoplication, the frequency and severity of symptoms of reflux (e.g., dysphagia, regurgitation, choking, heartburn, chest pain) were scored on a Likert scale (0 = never/not bothersome to 10 = always/very bothersome). For each patient, symptom scores before versus after fundoplication were compared using the Wilcoxon matched pairs test; comparisons of symptom scores among patients grouped by reflux patterns were made using Kruskal-Wallis test. RESULTS: Before fundoplication, the patterns of reflux did not affect the frequency or severity of reflux symptoms. After laparoscopic fundoplication, all symptoms of bipositional reflux improved, and essentially all symptoms of isolated supine or upright reflux or neither improved. CONCLUSIONS: Preoperatively, regardless of the patterns of reflux, symptoms among patients were similar. After fundoplication, symptoms of GERD improved for all patterns of reflux. Laparoscopic fundoplication imparts dramatic and broad relief of symptoms of GERD, regardless of the patterns of reflux. Application of laparoscopic Nissen fundoplication is encouraged.


Asunto(s)
Fundoplicación , Reflujo Gastroesofágico/fisiopatología , Reflujo Gastroesofágico/cirugía , Laparoscopía , Postura , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Satisfacción del Paciente , Índice de Severidad de la Enfermedad , Posición Supina , Resultado del Tratamiento
13.
Surg Endosc ; 21(12): 2183-6, 2007 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-17522934

RESUMEN

BACKGROUND: Recollection of preoperative symptom frequency and severity may change postoperatively, thus invalidating longitudinal studies. This study was undertaken to compare symptoms of achalasia before myotomy to patients' postoperative recollection of premyotomy symptoms. METHODS: A total of 173 patients, 54% male, of median age 48 years, have undergone laparoscopic Heller myotomy and have been followed through a prospectively maintained registry. Preoperatively, patients scored the frequency and severity of their symptoms on a Likert scale: 0 (never/very bothersome) to 10 (always/very bothersome). Similarly, after laparoscopic Heller myotomy, patients scored the frequency and severity of their symptoms, and re-scored their preoperative symptoms. Data are presented as median, mean +/- SD. RESULTS: Before myotomy, dysphagia, regurgitation, choking, chest pain, vomiting, and heartburn were particularly notable; symptom scores nearly globally improved after myotomy (p < 0.05 for all, Wilcoxon matched pairs test), especially obstructive symptoms. Postmyotomy recollection of premyotomy symptom frequency and severity was neither substantively nor consistently different from premyotomy scoring. CONCLUSIONS: Before myotomy, patient symptom scores reflected the deleterious impact of achalasia. After myotomy, patient symptom scores dramatically improved, reflecting the favorable impact of laparoscopic Heller myotomy. Even years after myotomy, patient recollection of premyotomy symptom severity and frequency is very accurate and supports longitudinal studies of symptom improvement after myotomy.


Asunto(s)
Acalasia del Esófago/fisiopatología , Acalasia del Esófago/cirugía , Laparoscopía , Recuerdo Mental , Adulto , Anciano , Acalasia del Esófago/psicología , Femenino , Humanos , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Sistema de Registros , Índice de Severidad de la Enfermedad , Resultado del Tratamiento
14.
J Phys Condens Matter ; 18(17): 4161-75, 2006 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-21690771

RESUMEN

We have studied the magnetic properties of (57)Fe-doped NiO nanoparticles using Mössbauer spectroscopy and magnetization measurements. Two samples with different degrees of interparticle interaction were studied. In both samples the particles were characterized by high-resolution transmission electron microscopy and x-ray diffraction and found to be plate-shaped. Computer simulations showed that high-field Mössbauer data are very sensitive to the size of the uncompensated magnetic moment. From analyses of the Mössbauer spectra we have estimated that the size of the uncompensated magnetic moment is in accordance with a model based on random occupation of surface sites. The analyses of the magnetization data gave larger magnetic moments, but the difference can be explained by the different sensitivity of the two methods to a particle size distribution and by interactions between the particles, which may have a strong influence on the moments estimated from magnetization data.

15.
Circulation ; 101(15): 1867-73, 2000 Apr 18.
Artículo en Inglés | MEDLINE | ID: mdl-10769290

RESUMEN

BACKGROUND: Interaction of complement with endothelial cells (ECs) underlies the development of inflammation and coagulation in disease. Assembly of the membrane attack complex (MAC) of complement on EC membrane, like stimulation with cytokines, upregulates tissue factor and cyclooxygenase-2 but does so via the intermediary action of IL-1alpha. We asked whether the MAC activates porcine aortic and microvascular ECs in a global manner by this mechanism and whether this mechanism is used by membrane pore-forming structures. METHODS AND RESULTS: Exposure of ECs to complement caused upregulation of mRNAs for E-selectin, intracellular adhesion molecule-1, vascular cell adhesion molecule-1, Ikappa-Balpha, interleukin (IL)-1alpha, IL-1beta, IL-8, and plasminogen activator inhibitor-1 over a period of 6 hours. The expression of these genes was not a primary response to stimulation, however, because IL-1 receptor antagonist inhibited expression of these genes. Activation of ECs by complement depended on the autocrine action of IL-1alpha, because complement-mediated EC activation was inhibited by anti-IL-1alpha antibodies. Melittin and mastoparan, amphiphilic pore-forming peptides like the MAC, induced E-selectin through intermediary action of IL-1. CONCLUSIONS: These findings suggest that transmembrane pore-forming proteins, as a class of molecules, activate ECs through the autocrine effects of IL-1alpha.


Asunto(s)
Complejo de Ataque a Membrana del Sistema Complemento/metabolismo , Endotelio Vascular/citología , Interleucina-1/metabolismo , Proteínas de la Membrana/metabolismo , Animales , Activación de Complemento/fisiología , Selectina E/metabolismo , Cinética , ARN Mensajero/metabolismo , Porcinos , Regulación hacia Arriba
16.
Mol Immunol ; 36(13-14): 965-71, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-10698351

RESUMEN

The complement system contributes critically to the barrier to transplantation of cells and organs. In the case of tissues and organs transplanted between individuals of the same species, that is in allotransplantation, the barrier posed by complement is seemingly eclipsed by the barrier posed by cellular immune responses. In the case of cells and organs transplanted between individuals of disparate species, that is xenotransplantation, the complement system has been thought to pose a nearly insurmountable barrier. With our understanding on how the complement system contributes to rejection, it is now clear that the complement system is more important in allotransplantation and more forgiving in xenotransplantation than was previously thought.


Asunto(s)
Proteínas del Sistema Complemento/metabolismo , Inmunología del Trasplante , Enfermedad Aguda , Animales , Activación de Complemento , Rechazo de Injerto/etiología , Rechazo de Injerto/inmunología , Humanos , Trasplante Heterólogo , Trasplante Homólogo
17.
J Invest Dermatol ; 83(1 Suppl): 67s-71s, 1984 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-6330225

RESUMEN

Three mouse strains as well as wt and 7 ts mutants of herpes simplex virus (HSV) type 2 (strain HG52) have been used to investigate latency. The mice were inoculated in the right rear footpad. Virus reactivation following explanation and culture of the dorsal root ganglia and the footpad was scored. The results show that: HSV-2 can be maintained in the mouse footpad in a state indistinguishable from latency; virus gene functions necessary for latency can be identified by the use of ts mutants; and mouse strains differ in their ability to support latent infection. An infectious center assay was used to quantitate virus reactivation from dissociated dorsal root ganglia. HSV-1 strain 17 wt spread after inoculation at doses of greater than or equal to 5.0 X 10(5) plaque-forming units (pfu), producing latency also in contralateral ganglia but with lower efficiency.


Asunto(s)
Pie/microbiología , Ganglios Espinales/microbiología , Herpes Simple/microbiología , Simplexvirus/patogenicidad , Animales , Genes Virales , Ratones , Ratones Endogámicos , Mutación , Simplexvirus/genética , Simplexvirus/aislamiento & purificación , Especificidad de la Especie , Activación Viral
18.
Immunol Res ; 16(3): 273-97, 1997.
Artículo en Inglés | MEDLINE | ID: mdl-9379077

RESUMEN

The transplantation of tissue and organs between individuals of different species, that is xenotransplantation, engenders a variety of severe immune responses. Xenogeneic immune responses mediated by naturally occurring antibodies and complement lead to hyperacute and acute vascular rejection of vascularized organ grafts and may also cause vascular rejection of cell and tissue grafts. Under some circumstances, however, a vascularized organ graft may evade humoral rejection despite the presence of antidonor antibodies in the circulation of the recipient; this condition is called accommodation. Xenogeneic immune responses mediated by T-lymphocytes and natural killer cells may cause acute cellular rejection. The extent to which cellular rejection of xenografts resembles cellular rejection of allografts remains to be determined. New insights into the molecular mechanisms underlying the immune responses to xenotransplantation have shed new light on the pathogenesis of immunological disease and have allowed the development of specific immunomodulatory strategies that may facilitate clinical application of xenotransplantation.


Asunto(s)
Trasplante de Órganos , Trasplante de Tejidos , Inmunología del Trasplante , Trasplante Heterólogo , Animales , Humanos , Células Asesinas Naturales/inmunología
19.
Transplantation ; 72(3): 509-15, 2001 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-11502984

RESUMEN

BACKGROUND: Platelets exert their normal functions at sites of endothelial disruption by plugging discontinuities in blood vessels and secreting products that promote thrombosis, inflammation, and the healing of wounds. Whether platelets might induce these changes in xenograft blood vessels, leading to development of acute vascular rejection, has been uncertain. METHODS: To examine the role of human platelets in modulation of xenograft endothelium, pig endothelial cells were treated with human platelets. RESULTS: Treatment of quiescent porcine endothelial cells with human platelets modulated the endothelial cells. Whereas resting human platelets caused little change in normal porcine endothelial cells, platelets activated with small amounts of thrombin induced striking changes in the endothelial cells, including the induction of tissue factor activity, the expression of E-selectin, and the secretion of endothelin-1. These changes were induced, at least in part, by interleukin-1 (IL-1) associated with the platelet surface and were modified by the secretion of transforming growth factor-beta (TGF-beta). CONCLUSION: These findings may explain how the activation of platelets at an early point in the rejection of vascularized organ xenografts or in chronic diseases might contribute to thrombotic, ischemic, and inflammatory changes characteristic of an organ xenograft undergoing rejection.


Asunto(s)
Plaquetas/fisiología , Endotelio Vascular/fisiología , Rechazo de Injerto/etiología , Trasplante Heterólogo , Animales , Selectina E/metabolismo , Endotelina-1/metabolismo , Endotelio Vascular/citología , Rechazo de Injerto/fisiopatología , Humanos , Interleucina-1/farmacología , Activación Plaquetaria , Porcinos , Tromboplastina/metabolismo , Factor de Crecimiento Transformador beta/farmacología
20.
Transplantation ; 61(1): 161-4, 1996 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-8560559

RESUMEN

In this study, we have investigated the early in vitro effects of natural killer (NK) cells on porcine aortic endothelial cell (PAEC) monolayers. Incubation of effector cells containing about 70% CD56+ cells on PAEC monolayer led to time-dependent changes in PAEC monolayer morphology. As little as 20 min of incubation resulted in changes in PAEC shape and in the appearance of gaps between the cells. These effects have been observed for up to 6 hr, but not before 20 min or after 6 hr. When NK-depleted effector cells were used, no morphological changes were observed in comparison with the same effectors before depletion; if CD56+ cells were added back, the effects were comparable with those on nondepleted effector cells. There was no detectable NK cell-mediated cytolytic activity during the 1-6 hr of incubation of peripheral blood lymphocytes with PAEC monolayers. These data indicate that NK cells may participate in endothelial cell changes leading to xenograft rejection.


Asunto(s)
Endotelio Vascular/citología , Células Asesinas Naturales/citología , Animales , Tamaño de la Célula , Células Cultivadas , Técnicas de Cocultivo , Endotelio Vascular/inmunología , Uniones Comunicantes , Rechazo de Injerto/inmunología , Humanos , Células Asesinas Naturales/inmunología , Porcinos
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