Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 79
Filtrar
Más filtros

Banco de datos
País/Región como asunto
Tipo del documento
Intervalo de año de publicación
1.
Epidemiol Infect ; 145(5): 1058-1068, 2017 04.
Artículo en Inglés | MEDLINE | ID: mdl-28029091

RESUMEN

Rift Valley fever virus (RVFV) is an emerging pathogen of major concern throughout Africa and the Arabian Peninsula, affecting both livestock and humans. In the past recurrent epidemics were reported in Mauritania and studies focused on the analysis of samples from affected populations during acute outbreaks. To verify characteristics and presence of RVFV during non-epidemic periods we implemented a multi-stage serological and molecular analysis. Serum samples of small ruminants, cattle and camels were obtained from Mauritania during an inter-epidemic period in 2012-2013. This paper presents a comparative analysis of potential variations and shifts of antibody presence and the capability of inter-epidemic infections in Mauritanian livestock. We observed distinct serological differences between tested species (seroprevalence: small ruminants 3·8%, cattle 15·4%, camels 32·0%). In one single bovine from Nouakchott, a recent RVF infection could be identified by the simultaneous detection of IgM antibodies and viral RNA. This study indicates the occurrence of a low-level enzootic RVFV circulation in livestock in Mauritania. Moreover, results indicate that small ruminants can preferably act as sentinels for RVF surveillance.


Asunto(s)
Anticuerpos Antivirales/sangre , Epidemias , ARN Viral/sangre , Fiebre del Valle del Rift/epidemiología , Virus de la Fiebre del Valle del Rift/aislamiento & purificación , Rumiantes , Animales , Mauritania/epidemiología , Fiebre del Valle del Rift/inmunología , Fiebre del Valle del Rift/virología , Virus de la Fiebre del Valle del Rift/genética , Virus de la Fiebre del Valle del Rift/inmunología , Estudios Seroepidemiológicos
2.
Kidney Int ; 89(3): 712-9, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26509590

RESUMEN

Intravital multiphoton microscopy is a powerful tool to study kidney physiology in living animals. However, certain technical issues have curbed its usage to date, including limited depth of tissue penetration and high background emission of endogenous signals. Most previous studies have used the excitation range 700­1000 nm. Since newer longer wavelength excitation lasers may provide solutions to these problems we constructed a microscope coupled to a laser tunable up to 1300 nm and optimized for kidney imaging. This set-up offers substantial advantages for intravital studies, especially when coupled with newly available far-red probes. First, the background at longer wavelengths is markedly reduced, thus increasing the signal to background ratio. Second, the depth of tissue penetration is significantly increased, enabling detailed imaging of previously inaccessible structures, such as deeper glomeruli. Third, using a combination of two- and three-photon excitation, multiple different fluorescent probes can be imaged simultaneously in the same animal, with clear spectral separation. Application of these techniques helped visualize pathological aspects of tubular cell function in a well-established model of acute kidney injury (maleate toxicity). Thus, utilizing long wavelength excitation offers substantial advantages for intravital kidney imaging, which together enhance the capabilities of this powerful and increasingly used research technique.


Asunto(s)
Lesión Renal Aguda/patología , Microscopía Intravital , Riñón/patología , Microscopía de Fluorescencia por Excitación Multifotónica , Lesión Renal Aguda/inducido químicamente , Animales , Modelos Animales de Enfermedad , Masculino , Maleatos , Ratones Endogámicos C57BL , Valor Predictivo de las Pruebas
3.
J Toxicol Environ Health A ; 74(2-4): 103-9, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21218339

RESUMEN

For almost two decades after the discovery of the first bovine spongiform encephalopathy (BSE) case, it was generally accepted that only one BSE strain existed globally. However, in 2004, two novel BSE forms (L-type and H-type) were separately identified in two different European Member States, forms that differed from the classical (C-type) form by their biochemical properties and by the pattern of PrP(Sc) deposition as determined by immunohistochemistry (IHC). 60 atypical BSE cases have been identified worldwide as of November 2010, including one H- and one L-type BSE case each in Germany. However, it was not known whether the biological properties (pathogenesis and agent distribution, as well as transmissibility to other species) of these novel forms were the same as in classical BSE cases. Eleven calves were thus challenged intracranially, five with the German H-type and six with German L-type BSE cases. The experimental design and the clinical studies, followed by laboratory testing, are described in this manuscript.


Asunto(s)
Encefalopatía Espongiforme Bovina/transmisión , Animales , Encéfalo/patología , Bovinos , Encefalopatía Espongiforme Bovina/patología , Femenino , Alemania , Immunoblotting/veterinaria , Periodo de Incubación de Enfermedades Infecciosas , Proteínas PrPSc/aislamiento & purificación , Proteínas PrPSc/patogenicidad , Priones/genética , Priones/aislamiento & purificación , Priones/patogenicidad
4.
Cereb Cortex Commun ; 1(1): tgaa052, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-34296117

RESUMEN

Neuronal circuits of the spinal dorsal horn integrate sensory information from the periphery with inhibitory and facilitating input from higher central nervous system areas. Most previous work focused on projections descending from the hindbrain. Less is known about inputs descending from the cerebral cortex. Here, we identified cholecystokinin (CCK) positive layer 5 pyramidal neurons of the primary somatosensory cortex (CCK + S1-corticospinal tract [CST] neurons) as a major source of input to the spinal dorsal horn. We combined intersectional genetics and virus-mediated gene transfer to characterize CCK+ S1-CST neurons and to define their presynaptic input and postsynaptic target neurons. We found that S1-CST neurons constitute a heterogeneous population that can be subdivided into distinct molecular subgroups. Rabies-based retrograde tracing revealed monosynaptic input from layer 2/3 pyramidal neurons, from parvalbumin positive cortical interneurons, and from thalamic relay neurons in the ventral posterolateral nucleus. Wheat germ agglutinin-based anterograde tracing identified postsynaptic target neurons in dorsal horn laminae III and IV. About 60% of these neurons were inhibitory and about 60% of all spinal target neurons expressed the transcription factor c-Maf. The heterogeneous nature of both S1-CST neurons and their spinal targets suggest complex roles in the fine-tuning of sensory processing.

5.
Infect Immun ; 77(2): 576-84, 2009 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19015255

RESUMEN

Mycoplasma suis belongs to the hemotrophic mycoplasma group and causes infectious anemia in pigs. According to the present state of knowledge, this organism adheres to the surface of erythrocytes but does not invade them. We found a novel M. suis isolate that caused severe anemia in pigs with a fatal disease course. Interestingly, only marginal numbers of the bacteria were visible on and between the erythrocytes in acridine orange-stained blood smears for acutely diseased pigs, whereas very high loads of M. suis were detected in the same blood samples by quantitative PCR. These findings indicated that M. suis is capable of invading erythrocytes. By use of fluorescent labeling of M. suis and examination by confocal laser scanning microscopy, as well as scanning and transmission electron microscopy, we proved that the localization of M. suis was intracellular. This organism invades erythrocytes in an endocytosis-like process and is initially surrounded by two membranes, and it was also found floating freely in the cytoplasm. In conclusion, we were able to prove for the first time that a member of the hemotrophic mycoplasma group is able to invade the erythrocytes of its host. Such colonization should protect the bacterial cells from the host's immune response and hamper antibiotic treatment. In addition, an intracellular life cycle may explain the chronic nature of hemotrophic mycoplasma infections and should serve as the foundation for novel strategies in hemotrophic mycoplasma research (e.g., treatment or prophylaxis).


Asunto(s)
Eritrocitos/microbiología , Infecciones por Mycoplasma/veterinaria , Mycoplasma/fisiología , Enfermedades de los Porcinos/microbiología , Animales , Eritrocitos/ultraestructura , Microscopía Confocal/veterinaria , Microscopía Electrónica de Rastreo , Microscopía Electrónica de Transmisión/veterinaria , Mycoplasma/ultraestructura , Infecciones por Mycoplasma/microbiología , Porcinos
6.
J Cell Biol ; 135(1): 253-67, 1996 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-8858178

RESUMEN

Neural cell adhesion molecules of the immunoglobulin/fibronectin type III family on axons have been implicated in promotion of neurite outgrowth, fasciculation, and the mediation of specific cell adhesion. The present study demonstrates that two of these molecules on dorsal root ganglion neurons are associated with distinct protein kinases, axonin-1 with the src-related nonreceptor tyrosine kinase fyn and NgCAM with a casein kinase II-related activity and a serine/ threonine kinase related to S6 kinase. When neurites grew without contacts involving axonin-1 and NgCAM, strong fyn kinase activity was associated with axonin-1, whereas the NgCAM-associated kinase activities were low. Clustering of axonin-1 with NgCAM induced by the formation of cell-cell contacts correlated with a reduction of the axonin-1-associated fyn activity and an increased phosphorylation of NgCAM by the associated casein kinase II-related activity. Thus, axonin-1 and NgCAM trigger distinctive intracellular signals during in vitro differentiation depending on their state of association.


Asunto(s)
Moléculas de Adhesión Celular Neurona-Glia/metabolismo , Moléculas de Adhesión Celular Neuronal/metabolismo , Neuritas/fisiología , Transducción de Señal/fisiología , Animales , Quinasa de la Caseína II , Moléculas de Adhesión Celular Neurona-Glia/química , Moléculas de Adhesión Celular Neuronal/química , Comunicación Celular/fisiología , Diferenciación Celular , Células Cultivadas , Embrión de Pollo , Contactina 2 , Inhibidores Enzimáticos/farmacología , Ganglios Espinales/fisiología , Genisteína , Heparina/farmacología , Isoflavonas/farmacología , Peso Molecular , Oligonucleótidos Antisentido , Fosforilación , Fosfotirosina/análisis , Pruebas de Precipitina , Proteínas Serina-Treonina Quinasas/metabolismo , Proteínas Tirosina Quinasas/antagonistas & inhibidores , Proteínas Proto-Oncogénicas/metabolismo , Proteínas Proto-Oncogénicas c-fyn , Proteínas Quinasas S6 Ribosómicas
7.
J Cell Biol ; 135(6 Pt 1): 1593-607, 1996 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-8978825

RESUMEN

The axonal surface glycoproteins neuronglia cell adhesion molecule (NgCAM) and axonin-1 promote cell-cell adhesion, neurite outgrowth and fasciculation, and are involved in growth cone guidance. A direct binding between NgCAM and axonin-1 has been demonstrated using isolated molecules conjugated to the surface of fluorescent microspheres. By expressing NgCAM and axonin-1 in myeloma cells and performing cell aggregation assays, we found that NgCAM and axonin-1 cannot bind when present on the surface of different cells. In contrast, the cocapping of axonin-1 upon antibody-induced capping of NgCAM on the surface of CV-1 cells coexpressing NgCAM and axonin-1 and the selective chemical cross-linking of the two molecules in low density cultures of dorsal root ganglia neurons indicated a specific and direct binding of axonin-1 and Ng-CAM in the plane of the same membrane. Suppression of the axonin-1 translation by antisense oligonucleotides prevented neurite outgrowth in dissociated dorsal root ganglia neurons cultured on an NgCAM substratum, indicating that neurite outgrowth on NgCAM substratum requires axonin-1. Based on these and previous results, which implicated NgCAM as the neuronal receptor involved in neurite outgrowth on NgCAM substratum, we concluded that neurite outgrowth on an NgCAM substratum depends on two essential interactions of growth cone NgCAM: a trans-interaction with substratum NgCAM and a cis-interaction with axonin-1 residing in the same growth cone membrane.


Asunto(s)
Moléculas de Adhesión Celular Neurona-Glia/fisiología , Moléculas de Adhesión Celular Neuronal/fisiología , Neuritas/fisiología , Secuencia de Aminoácidos , Animales , Anticuerpos/inmunología , Secuencia de Bases , Células COS , Moléculas de Adhesión Celular Neurona-Glia/química , Moléculas de Adhesión Celular Neuronal/química , Moléculas de Adhesión Celular Neuronal/inmunología , Agregación Celular , Línea Celular , Membrana Celular/química , Membrana Celular/fisiología , Embrión de Pollo , Contactina 2 , ADN , Dimerización , Datos de Secuencia Molecular , Reacción en Cadena de la Polimerasa , Transcripción Genética , Células Tumorales Cultivadas
8.
Gesundheitswesen ; 71(5): 281-90, 2009 May.
Artículo en Alemán | MEDLINE | ID: mdl-19288422

RESUMEN

So far all calculations of the number of demented people are based on rates from meta-analyses, mean rates of meta-analyses or spatial analyses. This article presents age- and gender-specific prevalence and incidence rates of dementia that are based on a large sample of the German Sick Funds (Stichprobendaten von Versicherten der gesetzlichen Krankenversicherung (GKV)) with 2.3 million people from the year 2002. Prevalence rates increase from 0.8% and 0.6% for 60-64 year old men and women to 30% and 43% for men and women aged 100 or older, respectively. Incidence rates increase from 0.18 and 0.14 cases per 100 person-years for 60-64-year old men and women to 9.9 and 10.9 for over 95 year old men and women, respectively. Our results confirm rates from earlier studies on the basis of meta-analyses. Regional differences show for the first time that higher prevalence rates exist for East German women and men above age 85. In 2007 about 1.07 million moderately or severely demented people live in Germany of which about 244 000 are incident cases when we extrapolate our rates to the population of this year.


Asunto(s)
Demencia/epidemiología , Programas Nacionales de Salud/estadística & datos numéricos , Distribución por Edad , Anciano , Anciano de 80 o más Años , Demencia/economía , Femenino , Alemania/epidemiología , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Prevalencia , Medición de Riesgo/métodos , Factores de Riesgo , Distribución por Sexo
9.
Anim Genet ; 39(4): 400-6, 2008 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18513278

RESUMEN

Bovine spongiform encephalopathy (BSE) belongs to a group of neurodegenerative diseases known as transmissible prion diseases. Recently, variants in the promoter region of the prion protein (PRNP) gene have been shown to have a considerable effect on the susceptibility to BSE. However, a previous genome scan revealed other putative BSE-susceptibility loci. Here, we analysed such a region on BTA10, which contains the functional candidate gene HEXA. Three hundred and twenty kilobases that, besides HEXA, also contain ARIH1, BRUNOL6 and PARP6 were characterized and screened for polymorphisms. Genotyping of 38 SNPs in Holstein-Friesian animals from the UK (350 diseased and 270 controls) revealed two intronic SNPs that were associated with BSE incidence, with experiment-wise P-values of 3.5 x 10(-3) and 7.7 x 10(-3) respectively. Both SNPs were in strong linkage disequilibrium and the rare alleles had a protective effect. These alleles were contained in a haplotype dubbed 'UK-protective' that was significantly overrepresented in the controls with a permuted P-value of 2 x 10(-3). An association study in German Holstein animals (73 diseased and 627 controls) revealed an opposite effect of the 'UK-protective' haplotype in this population, i.e. it was overrepresented in the diseased animals, although not significant after correction for multiple testing. These findings indicate a causal variant for BSE susceptibility on BTA10 in linkage disequilibrium with the markers studied. Candidate gene analyses of the surrounding region and additional association studies will help to clarify the origin of the protective effects and to identify causal variants for BSE susceptibility on BTA10.


Asunto(s)
Bovinos/genética , Encefalopatía Espongiforme Bovina/genética , Predisposición Genética a la Enfermedad , Hexosaminidasa A/genética , Polimorfismo de Nucleótido Simple , Animales , Cromosomas Artificiales Bacterianos , Cromosomas de los Mamíferos/genética , Biblioteca Genómica , Haplotipos , Intrones , Desequilibrio de Ligamiento , Alineación de Secuencia , Análisis de Secuencia de ADN
10.
Acta Physiol (Oxf) ; 222(1)2018 01.
Artículo en Inglés | MEDLINE | ID: mdl-28580772

RESUMEN

AIMS: (i) To determine whether exercise-induced increases in muscle mitochondrial volume density (MitoVD ) are related to enlargement of existing mitochondria or de novo biogenesis and (ii) to establish whether measures of mitochondrial-specific enzymatic activities are valid biomarkers for exercise-induced increases in MitoVD . METHOD: Skeletal muscle samples were collected from 21 healthy males prior to and following 6 weeks of endurance training. Transmission electron microscopy was used for the estimation of mitochondrial densities and profiles. Biochemical assays, western blotting and high-resolution respirometry were applied to detect changes in specific mitochondrial functions. RESULT: MitoVD increased with 55 ± 9% (P < 0.001), whereas the number of mitochondrial profiles per area of skeletal muscle remained unchanged following training. Citrate synthase activity (CS) increased (44 ± 12%, P < 0.001); however, there were no functional changes in oxidative phosphorylation capacity (OXPHOS, CI+IIP ) or cytochrome c oxidase (COX) activity. Correlations were found between MitoVD and CS (P = 0.01; r = 0.58), OXPHOS, CI+CIIP (P = 0.01; R = 0.58) and COX (P = 0.02; R = 0.52) before training; after training, a correlation was found between MitoVD and CS activity only (P = 0.04; R = 0.49). Intrinsic respiratory capacities decreased (P < 0.05) with training when respiration was normalized to MitoVD. This was not the case when normalized to CS activity although the percentage change was comparable. CONCLUSIONS: MitoVD was increased by inducing mitochondrial enlargement rather than de novo biogenesis. CS activity may be appropriate to track training-induced changes in MitoVD.


Asunto(s)
Entrenamiento Aeróbico , Mitocondrias Musculares/metabolismo , Mitocondrias Musculares/ultraestructura , Músculo Esquelético/metabolismo , Músculo Esquelético/ultraestructura , Adulto , Citrato (si)-Sintasa/análisis , Humanos , Masculino , Biogénesis de Organelos , Fosforilación Oxidativa , Adulto Joven
11.
Curr Biol ; 6(9): 1153-8, 1996 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-8805367

RESUMEN

BACKGROUND: Growth cones at the tips of growing axons move along predetermined pathways to establish synaptic connections between neurons and their distant targets. To establish their orientation, growth cones continuously sample for, and respond to, guidance information provided by cell surfaces and the extracellular matrix. To identify specific guidance cues, growth cones have sensor molecules on their surface, which are expressed differentially during the temporospatial progress of axon outgrowth, at levels that depend on the pattern of neural activity. However, it has not been elucidated whether a change in gene expression can indeed change the molecular composition and, hence, the function of the sensor apparatus of growth cones. RESULTS: We have constructed adenoviral gene transfer vectors of the chicken growth cone sensor molecules axonin-1 and Ng-CAM. Using these vectors, we initiated the expression of axonin-1 and Ng-CAM in rat dorsal root ganglia explants during ongoing neurite outgrowth. Using specific surface immunodetection at varying time points after infection, we found that axonin-1 and Ng-CAM are transported directly to the growth cone and inserted exclusively in the growth cone membrane and not in the axolemma of the axon shaft. Furthermore, we found that axonin-1 and Ng-CAM do not diffuse retrogradely, suggesting that the sensor molecules are integrated into multimolecular complexes in the growth cone. CONCLUSIONS: During axon outgrowth, the pathway sensor apparatus of the growth cone is continuously updated by newly synthesized sensor molecules that originate directly from the transcription/translation machinery. Changes in the expression of sensor molecules may have a direct impact, therefore, on the exploratory function of the growth cone.


Asunto(s)
Axones , Neuritas , Animales , Axones/metabolismo , Moléculas de Adhesión Celular Neurona-Glia/metabolismo , Moléculas de Adhesión Celular Neuronal/metabolismo , Embrión de Pollo , Contactina 2 , Ganglios Espinales/citología , Ganglios Espinales/metabolismo , Inmunohistoquímica , Ratas
12.
Transbound Emerg Dis ; 64(6): 2049-2058, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28116860

RESUMEN

Rift Valley fever virus (RVFV) causes consistently severe outbreaks with high public health impacts and economic losses in livestock in many African countries and has also been introduced to Saudi Arabia and Yemen. Egypt with its four large outbreaks in the last 40 years represents the northernmost endemic area of RVFV. The purpose of this study was to provide an insight into the current anti-RVFV antibody status in immunized as well as non-immunized dairy cattle from the Nile Delta of Egypt. During 2013-2015, a total of 4,167 dairy cattle from four governorates including Dakahlia, Damietta, Gharbia and Port Said were investigated. All cattle were born after 2007 and therewith after the last reported Egyptian RVFV outbreak in 2003. The samples derived from vaccinated animals from 26 different dairy farms as well as non-immunized cattle from 27 different smallholding flocks. All samples were examined following a three-part analysis including a commercially available competition ELISA, an in-house immunofluorescence assay and a virus neutralization test. Additionally, a subset of samples was analysed for acute infections using IgM ELISA and real-time reverse transcriptase PCR. The results indicated that the RVFV is still circulating in Egypt as about 10% of the non-immunized animals exhibited RVFV-specific antibodies. Surprisingly, the antibody prevalence in immunized animals was not significantly higher than that in non-vaccinated animals which points out the need for further evaluation of the vaccination programme. Due to the substantial role of livestock in the amplification and transmission of RVFV, further recurrent monitoring of the antibody prevalence in susceptible species is highly warranted.


Asunto(s)
Anticuerpos Antivirales/sangre , Enfermedades de los Bovinos/epidemiología , Fiebre del Valle del Rift/epidemiología , Virus de la Fiebre del Valle del Rift/inmunología , Animales , Bovinos , Enfermedades de los Bovinos/transmisión , Enfermedades de los Bovinos/virología , Industria Lechera , Brotes de Enfermedades/veterinaria , Egipto/epidemiología , Ensayo de Inmunoadsorción Enzimática/veterinaria , Monitoreo Epidemiológico , Femenino , Ganado , Prevalencia , Fiebre del Valle del Rift/transmisión , Fiebre del Valle del Rift/virología , Vacunación/veterinaria
13.
Acta Trop ; 172: 7-13, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28427961

RESUMEN

Rift Valley fever virus (RVFV) is an arthropod-borne pathogen, causing serious epidemics in Africa and the Arabian Peninsula. In Cameroon serological data indicate the presence of RVFV, but active circulation of RVFV, causing clinical infections has not been proven yet. For this purpose we carried out a serological and molecular study on a total of 1953 randomly selected serum samples of small ruminants and cattle, which were collected in years 2013 and 2014 in Cameroon. In a first step, sera were screened serologically using a variety of assay formats to reveal RVFV specific antibodies. At the second stage, seropositive specimen were assessed for acute RVFV infections via IgM-specific ELISA and quantitative real-time RT-PCR. Our data show a significant difference in the antibody prevalence in cattle (13.5% [95% confidence interval: 11.4-15.7]) and small ruminants (3.4% [95% confidence interval: 2.3-4.7]), with indications for annual fluctuations and significant regional differences of seropositivity. One small ruminant and three bovines were eventually found to be positive in IgM ELISA and indications for viremia were found in one bovine by RVFV genome detection using quantitative real-time RT-PCR. The results of this study therefore corroborate the presence of acute RVFV-infection and its circulation in Cameroon.


Asunto(s)
Ganado/virología , Fiebre del Valle del Rift/epidemiología , Virus de la Fiebre del Valle del Rift/inmunología , Rumiantes/virología , Animales , Anticuerpos Antivirales/sangre , Camerún/epidemiología , Bovinos , Ensayo de Inmunoadsorción Enzimática/veterinaria , Prevalencia , Reacción en Cadena en Tiempo Real de la Polimerasa , Estudios Seroepidemiológicos
14.
Surg Endosc ; 20(10): 1607-13, 2006 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16823647

RESUMEN

BACKGROUND: Postoperative systemic immune function is suppressed after open abdominal surgery, as compared with that after minimally invasive abdominal surgery. As a first line of defense, peritoneal macrophages (PMo) and polymorphonuclear neutrophil granulocytes (PMNs) are of primary importance in protecting the body from microorganisms. Previous studies have shown changes in these cell populations over time after open versus laparoscopic surgery. This study aimed to investigate the dynamics of cell recruitment and clearance of peritoneal cells. METHODS: Female NMRI mice (33 +/- 2 g) were randomly assigned to carbon dioxide (CO2) or air insufflation. Intravasal cells with phagocytic capabilities were selectively stained by intravenous injection of the fluorescent dye PKH26 24 h before surgery. Gas was insufflated into the peritoneal cavity through a catheter, and the pneumoperitoneum was maintained for 30 min. Peritoneal lavage was performed 1, 3, 8, or 24 h after surgery. Apoptotic cells were assessed by flow cytometry using a general caspase substrate. RESULTS: The total peritoneal cell count did not differ between groups. The PKH26-positive PMo level was significantly increased after CO2, as compared with air, at 1 h and 24 h. The ratio of apoptotic PMo did not differ between the groups. In the peritoneal lavage, polymorphonuclear leukocytes (PMNs) were tripled in the air group, as compared with the CO2 group, whereas the ratio of apoptotic PMNs was significantly decreased. There was a higher fraction of PKH26-positive PMNs after air exposure, as compared with that after CO2. CONCLUSIONS: Air exposure triggered a higher transmigration rate of PMNs from the blood compartment into the peritoneal cavity and decreased PMN apoptosis, as compared with CO2. The lower proportion of PKH26-positive peritoneal macrophages in the air group might have been attributable to a higher inflammatory stimulation than in the CO2 group, leading to increased emigration of PMo to draining lymph nodes. All the findings underscore a complex cell-specific regulation of cell recruitment and clearance in the peritoneal compartment.


Asunto(s)
Aire , Dióxido de Carbono/administración & dosificación , Neutrófilos/fisiología , Peritoneo/citología , Neumoperitoneo Artificial , Animales , Apoptosis , Movimiento Celular , Femenino , Citometría de Flujo , Colorantes Fluorescentes , Laparoscopía , Recuento de Leucocitos , Ratones , Compuestos Orgánicos , Fagocitosis
15.
Biochim Biophys Acta ; 1373(2): 289-98, 1998 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-9733986

RESUMEN

Monomolecular layers at the air-water interface were formed directly with isolated largest light-harvesting pigment-protein complex of Photosystem II (LHC II) or out of egg yolk lecithin (EYL) liposomes containing incorporated LHC II. Pure protein monolayers showed a mean area of 1400 A2 per molecule at the air-water interface. Monolayers were deposited onto glass slides by means of Langmuir-Blodgett (LB) technique. Chlorophyll fluorescence of LHC II-LB and EYL-LHC II-LB films proved energetic coupling of chlorophyll a and b, thus indicating native conformation of LHC II within the monolayers. Scanning force microscopy (SFM) revealed ring-like structures formed in monocomponent protein layers as well as in mixed protein-lipid films. These results suggest that a structural arrangement of LHC II is favoured in a lipid environment but that the protein has itself a strong tendency for structural complex rearrangement in our system.


Asunto(s)
Metabolismo de los Lípidos , Proteínas del Complejo del Centro de Reacción Fotosintética/química , Secale/química , Clorofila/química , Complejos de Proteína Captadores de Luz , Liposomas/metabolismo , Proteínas de la Membrana/química , Microscopía de Fuerza Atómica , Fosfatidilcolinas/metabolismo , Complejo de Proteína del Fotosistema II , Hojas de la Planta/química , Proteínas de Plantas/química , Presión , Conformación Proteica , Espectrometría de Fluorescencia , Espectrofotometría , Propiedades de Superficie
16.
FEBS Lett ; 436(2): 179-84, 1998 Oct 02.
Artículo en Inglés | MEDLINE | ID: mdl-9781674

RESUMEN

Scanning probe microscopy has the potential for investigating membranes in a physiological environment. We prepared with a lysis-squirting protocol basal cell membranes, that are suitable for scanning probe microscopy. Investigations using atomic force microscopy under liquid revealed cellular filaments which correlated perfectly with fluorescently stained actin filaments. Globular structures with a diameter as little as 10 nm could be resolved by stripping cytoplasmic components from the membranes. Therefore, cytoplasmic sides of supported basal cell membranes prove useful to gain high resolution with scanning probe microscopy in studies of plasma membrane associated structures and processes under buffer solution.


Asunto(s)
Membrana Celular/ultraestructura , Animales , Línea Celular , Perros , Riñón , Microscopía de Fuerza Atómica/métodos , Microscopía Electrónica , Microscopía Fluorescente , Sensibilidad y Especificidad
17.
J Heart Lung Transplant ; 10(3): 342-50, 1991.
Artículo en Inglés | MEDLINE | ID: mdl-1854762

RESUMEN

Long-term hemodynamic evaluation after heart transplantation has rarely been reported. Fifty-seven heart transplant recipients (mean age, 42.1 years: range, 22 to 56 years) were investigated with annual cardiac catheterization. Mean follow-up was 2.2 years (range, 1 to 7 years). Years 1 through 5 were evaluated statistically. Hemodynamic variables did not change significantly during the 5-year period. Mean aortic pressure (105 +/- 16 to 115 +/- 17 mm Hg, minimum and maximum annual average value +/- SD of the 5-year period) and LVEDP (13 +/- 6 to 15 +/- 7 mm Hg) were slightly elevated. Borderline values were found for mean pulmonary artery pressure (18 +/- 4 to 21 +/- 5 mm Hg), systemic vascular resistance (1407 +/- 227 to 1487 +/- 409 dynes.sec.cm-5), pulmonary vascular resistance (86 +/- 42 to 118 +/- 66 dynes.sec.cm-5), and heart rate (85 +/- 17 to 95 +/- 14 beats/min). Mean right atrial pressure (5 +/- 2 to 8 +/- 4 mm Hg), cardiac index (2.8 +/- 0.6 to 3.5 +/- 1.1 L/min/m2), end-diastolic volume (111 +/- 37 to 137 +/- 35 ml) and ejection fraction (69% +/- 10% to 75% +/- 9%) were in the normal range. Pressure-volume loops for each year excluded the development of either restrictive or dilated cardiomyopathy with time. Contractility, as measured by imposing afterload stress, was normal in 12 of 14 representative patients. Prevalence of coronary abnormalities (circumscript coronary stenoses, diffuse vessel obliteration or dilated angiopathy) increased from 14.9% in the first to 66.7% in the fifth year. Of the patients, 93% received antihypertensive drugs.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Trasplante de Corazón/fisiología , Hemodinámica/fisiología , Adulto , Cateterismo Cardíaco , Cardiomiopatía Dilatada/epidemiología , Cardiomiopatía Restrictiva/epidemiología , Enfermedad de la Arteria Coronaria/epidemiología , Estudios de Seguimiento , Rechazo de Injerto , Trasplante de Corazón/efectos adversos , Humanos , Hipertensión/epidemiología , Terapia de Inmunosupresión , Contracción Miocárdica/fisiología , Factores de Tiempo
18.
J Heart Lung Transplant ; 13(3): 438-42; discussion 442-3, 1994.
Artículo en Inglés | MEDLINE | ID: mdl-8061020

RESUMEN

OKT3 is recommended as rescue therapy for cases of steroid-resistant, clinically persistant acute rejection episodes after heart transplantation. In this study we determined the efficacy of such treatment. One hundred thirty-two patients were included in this study. The postoperative immunosuppressive regimen consisted of triple-drug therapy and perioperative antithymocyte globulin. During a follow-up of 10 to 108 weeks (mean, 51 +/- 20 weeks) 281 treatment-requiring acute rejection episodes (International Society for Heart and Lung Transplantation > or = II) were observed. In 29 cases (10.3%) the grade of the acute rejection episodes was either unchanged after two series of intravenous steroid pulse therapy, was worsened after the first steroid course, or the patient experienced clinical deterioration as a result of the acute rejection episodes. These patients were considered to have steroid-resistant acute rejection episodes and received a 10-day rescue therapy with OKT3, followed by control endomyocardial biopsy. In 17 cases, control endomyocardial biopsy revealed normal myocardium (group I). In 10 cases acute rejection episodes remained unchanged (group II); twice a deterioration was found (group III). However, 12 of the 17 patients from group I experienced a rebound of the acute rejection episodes (International Society for Heart and Lung Transplantation > or = II) 1 to 3 weeks later. Side effects of OKT3 treatment were fever, chills, intestinal complications, hemodynamic response, convulsions, and viral infections.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Rechazo de Injerto/terapia , Trasplante de Corazón/efectos adversos , Metilprednisolona/uso terapéutico , Muromonab-CD3/uso terapéutico , Enfermedad Aguda , Adolescente , Adulto , Anciano , Suero Antilinfocítico/uso terapéutico , Azatioprina/uso terapéutico , Biopsia , Niño , Ciclosporina/uso terapéutico , Femenino , Estudios de Seguimiento , Rechazo de Injerto/tratamiento farmacológico , Rechazo de Injerto/patología , Humanos , Masculino , Metotrexato/efectos adversos , Metotrexato/uso terapéutico , Persona de Mediana Edad , Muromonab-CD3/efectos adversos , Prednisona/uso terapéutico , Terapia Recuperativa
19.
J Neurosci Methods ; 61(1-2): 159-67, 1995.
Artículo en Inglés | MEDLINE | ID: mdl-8618415

RESUMEN

We have examined the influence of amino acids on chicken embryonic dorsal root ganglion (DRG) neurons in vitro and have found that serine has a marked impact on the morphology of the developing neurites. In cultures supplemented with L-serine (but not D-serine) at micromolar concentrations (10-200 microM), the length of the neurites was increased by up to 100% and they were seen to develop a more complex branching pattern. These effects of L-serine were found to be concentration-dependent and stereospecific and were observed on several different substrata such as laminin, Ng-CAM and axonin-1. Similar observations were also made in the case of embryonic retinal explants, while the addition of non-essential amino acids other than L-serine to DRG neurons was found to have no effect. We conclude that, although belonging to the group of non-essential amino acids and not a recognized neurotransmitter, L-serine is an important factor for the morphological differentiation of neurons in vitro.


Asunto(s)
Ganglios Espinales/efectos de los fármacos , Neuritas/efectos de los fármacos , Serina/farmacología , Animales , Recuento de Células/efectos de los fármacos , Embrión de Pollo , Técnicas In Vitro , Neuronas/efectos de los fármacos
20.
J Neurosci Methods ; 71(1): 99-111, 1997 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-9125379

RESUMEN

By homologous recombination, a first-generation adenovirus-based gene transfer vector, AdCMVax-1, was constructed as a means of manipulating the expression level of the axonal cell adhesion molecule axonin-1 in neurons and glial cells. AdCMVax-1 harbours the entire coding region of the chicken axonin-1 cDNA under the transcriptional control of the Cytomegalovirus enhancer/promoter in the early-region 1 of the viral genome. Characterization of AdCMVax-1 in vitro revealed highly efficient gene transfer and expression of recombinant axonin-1 in neurons and glial cells of dissociated rat dorsal root ganglia. Similar to its native counterpart, virus-derived axonin-1 was detected on the cell body, neurites, and growth cones of transduced neurons, occurred in a secreted and membrane-associated form, and could be cleaved from the membrane with phosphatidylinositol-specific phospholipase C. Functional characterization of recombinant axonin-1 revealed the same binding properties as previously reported for native axonin-1 isolated from the vitreous fluid of chicken embryos. In vivo gene transfer was studied by stereotactic injection of AdCMVax-1 in the dentate gyrus of the hippocampus and the facial nucleus in the brainstem of adult Wistar rats and revealed high level expression of recombinant axonin-1 in a subset of hippocampal neurons and motor neurons in the facial nucleus.


Asunto(s)
Adenovirus Humanos/genética , Moléculas de Adhesión Celular Neuronal/genética , Virus Defectuosos/genética , Vectores Genéticos , Neuronas/metabolismo , Animales , Moléculas de Adhesión Celular Neuronal/biosíntesis , Contactina 2 , Citomegalovirus/genética , ADN Complementario/genética , Giro Dentado/metabolismo , Giro Dentado/virología , Elementos de Facilitación Genéticos , Nervio Facial/metabolismo , Nervio Facial/virología , Ganglios Espinales/citología , Ganglios Espinales/embriología , Regulación de la Expresión Génica , Genoma Viral , Células HeLa , Humanos , Inyecciones , Ratones , Neuronas/virología , Regiones Promotoras Genéticas , Ratas , Ratas Wistar , Proteínas Recombinantes de Fusión/biosíntesis , Proteínas Recombinantes de Fusión/genética , Técnicas Estereotáxicas , Transcripción Genética , Células Tumorales Cultivadas
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA