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1.
Exp Parasitol ; 260: 108725, 2024 May.
Article de Anglais | MEDLINE | ID: mdl-38458554

RÉSUMÉ

Duddingtonia flagrans is a nematophagous fungus which has shown promising results as a non-chemical parasitic control tool. The fungus disrupts the parasite's life cycle by trapping larvae in the environment through the networks generated from chlamydospores, thus preventing the reinfection of animals. One barrier to the development of a commercial product using this tool is the need to increase chlamydospore production in the laboratory for its administration to livestock. The purpose of this study was to evaluate the addition of mannitol to an enriched culture medium and the effect of adverse cultivation conditions on chlamydospore production. D. flagrans was cultivated on Petri dishes with corn agar for 4 weeks at 27 °C and 70% relative humidity (RH). Four groups were then formed, all with Sabouraud agar as a base, to which different growth inducers were added: GSA (glucose Sabouraud agar), GSA-MI (glucose Sabouraud agar + meso inositol), GSA-E (enriched glucose Sabouraud agar), and AE-M (enriched agar + mannitol). After 4 weeks, chlamydospores were recovered by washing the surface of each plate with distilled water and then quantified. The medium that yielded the highest amount of chlamydospores was subjected to different cultivation conditions: NC (normal conditions): 70% RH and 27 °C, AC (adverse conditions) 1: 20% RH and 40 °C, CA2: 60% RH and 27 °C, and CA3: 55% RH and 24 °C. It was determined that mannitol increases chlamydospore production (65x106 chlamydospores/plate), and when reducing humidity by 10% under cultivation conditions it resulted in an approximately 10% increase in chlamydospore production compared to the control group. These results suggest that the addition of polyols, as well as its cultivation under certain environmental conditions, can improve chlamydospore production on a laboratory scale.


Sujet(s)
Agar-agar , Milieux de culture , Duddingtonia , Mannitol , Spores fongiques , Mannitol/pharmacologie , Milieux de culture/composition chimique , Spores fongiques/croissance et développement , Duddingtonia/croissance et développement , Duddingtonia/physiologie , Glucose/métabolisme , Animaux , Inositol/pharmacologie , Humidité , Température , Agents de lutte biologique/pharmacologie
2.
Arch. Soc. Esp. Oftalmol ; 98(1): 58-61, ene. 2023. ilus
Article de Espagnol | IBECS | ID: ibc-214333

RÉSUMÉ

Se describen 4 casos clínicos de pacientes con desprendimiento de retina regmatógeno (DRR) asociado a elevación de presión intraocular (PIO) en el momento del diagnóstico del DRR. Todos los pacientes eran hombres que acudieron a urgencias por miodesopsias, presentaban inflamación leve a moderada en cámara anterior y elevación de la presión intraocular mayor de 30mmHg. En todos ellos se detectó la presencia de DRR. Esto demuestra que los desprendimientos de retina no siempre presentan la PIO baja, y es compatible con valores de PIO alta. En esos casos de enfermedad retiniana y PIO elevada, se debe examinar minuciosamente la cámara anterior y el fondo de ojo para que no pase desapercibido un desprendimiento de retina que requiere tratamiento inmediato. Esta asociación de una PIO elevada y un DRR se denomina síndrome de Schwartz-Matsuo (AU)


Four clinical cases of patients with rhegmatogenous retinal detachment (RRD) associated with elevated intraocular pressure (IOP) are described. All the patients were men who came to the emergency service with floaters, all presented mild to moderate inflammation in the anterior chamber and increased intraocular pressure greater than 30mmHg. All were diagnosed of RRD. This demonstrates that a RRD does not always present low IOP. In these cases of clinical retinal pathology and high IOP, we must carefully examine the anterior chamber and the fundus of the eye so that an associated retinal detachment does not remain unnoticed, and can be treated immediately. This association of elevated IOP and RRD is called as Schwartz-Matsuo Syndrome (AU)


Sujet(s)
Humains , Mâle , Adulte d'âge moyen , Décollement de la rétine/imagerie diagnostique , Décollement de la rétine/complications , Pression intraoculaire
3.
Arch Soc Esp Oftalmol (Engl Ed) ; 98(1): 58-61, 2023 Jan.
Article de Anglais | MEDLINE | ID: mdl-36371054

RÉSUMÉ

Four clinical cases of patients with rhegmatogenous retinal detachment (RRD) associated with elevated intraocular pressure (IOP) are described. All the patients were men who came to the emergency service with floaters, all presented mild to moderate inflammation in the anterior chamber and increased intraocular pressure greater than 30 mmHg. All were diagnosed of RRD. This demonstrates that a RRD does not always present low IOP. In these cases of clinical retinal pathology and high IOP, we must carefully examine the anterior chamber and the fundus of the eye so that an associated retinal detachment does not remain unnoticed, and can be treated immediately. This association of elevated IOP and RRD is called as Schwartz-Matsuo Syndrome.1.


Sujet(s)
Glaucome , Décollement de la rétine , Mâle , Humains , Femelle , Décollement de la rétine/complications , Pression intraoculaire , Glaucome/complications , Rétine/anatomopathologie , Chambre antérieure du bulbe oculaire/anatomopathologie
4.
Med Oral Patol Oral Cir Bucal ; 27(3): e248-e256, 2022 May 01.
Article de Anglais | MEDLINE | ID: mdl-35368011

RÉSUMÉ

BACKGROUND: Oral mucositis is one of the most common side effects in cancer patients receiving systemic antineoplastics. However, the underlying biological mechanisms leading to this condition are still unclear. For this reason, it has been hypothesised that systemic antineoplastics may cause an imbalance on the oral microbiota that subsequently triggers oral mucosa damage. MATERIAL AND METHODS: A systematic review was performed following the PRISMA protocol and the PICO question established was: patients diagnosed with cancer, who are candidates for receiving systemic antineoplastics (P=Patients), that undergo oral microbiome determinations (I=Intervention), before and after systemic antineoplastics administration (C=Comparison), to analyse changes in the oral microbiome composition (O=Outcome). The bibliographic search was carried out in PubMed and other scientific repositories. RESULTS: Out of 166 obtained articles, only 5 met eligibility criteria. Acute myeloid leukaemia (AML) was the most frequent type of cancer (40 %) among the participants. Only one of the studies included a control group of healthy subjects. Heterogeneity in the protocols and approaches of the included studies hindered a detailed comparison of the outcomes. However, it was stated that a decrease in bacteria α diversity is often associated with oral mucositis. On the other hand, fungal diversity was not associated with oral mucositis although α diversity was lower at baseline on patients developing oral candidiasis. CONCLUSIONS: There is insufficient scientific evidence of oral microbiological changes in patients undergoing systemic antineoplastics. Further investigations ought to be carried out to identify microorganisms that might play a key role in the pathogenesis of oral mucosa damage in patients undergoing systemic antineoplastics.


Sujet(s)
Antinéoplasiques , Candidose buccale , Microbiote , Tumeurs , Stomatite , Antinéoplasiques/effets indésirables , Candidose buccale/traitement médicamenteux , Humains , Tumeurs/complications , Tumeurs/traitement médicamenteux
5.
Phys Chem Chem Phys ; 14(37): 13058-66, 2012 Oct 05.
Article de Anglais | MEDLINE | ID: mdl-22890231

RÉSUMÉ

Excitation properties of the isolated C(60) and (C(60))(N) model clusters (N = 2, 3, 4, 6 and 13) are studied using an a priori parameterized and self-consistent Hamiltonian, the Complete Neglect of Differential Overlap considering the l azimuthal quantum number method. This method properly describes electron excitations of the isolated C(60) after the configuration interaction of singles (CIS) procedure, when those are compared with experimental data in n-hexane solution and in a molecular beam. Geometry models of (C(60))(N) clusters to model the effect of aggregation were obtained from the fullerene fcc crystal. Some peaks in the low energy edge of the absorption spectrum appear corresponding to clustering effects, as well as small increases of bandwidths in the strong bands at the UV region. An analysis of the theoretical absorption spectrum for dimer models has been carried out, taking into account the influence of the distance between fullerene centers. The density of states of CIS for fullerene clusters in the range from 2.0 to 6.5 eV shows the possibility of electron transitions as functions of the size of the clusters.

6.
J Mech Behav Biomed Mater ; 4(7): 1011-20, 2011 Oct.
Article de Anglais | MEDLINE | ID: mdl-21783111

RÉSUMÉ

Hydroxyapatite (HAP) and fluorapatite (FAP) are essential components of dental enamel and bone. In this paper, we report a computational study of the elastic properties of HAP and FAP using ab initio and force field techniques. We have obtained the HAP and FAP elastic stiffness constants in hexagonal symmetry by fitting the Hooke law for both the energy-strain and stress-strain relations. Our ab initio HAP stiffness constants differ from the results of previous calculations, but follow similar trends. The HAP and FAP stiffness constants calculated with the ab initio method are very similar, although FAP is slightly stiffer than HAP in the hexagonal plane, and more compliant along the hexagonal axis. The pseudo-single-crystal HAP experimental stiffness constants in current use are critically reviewed. Combining the data from the ab initio simulations with the experimental FAP stiffness constants, several alternative sets of HAP stiffness constants are proposed. The mismatch in properties between HAP and FAP is evidently too small to assume it to be directly responsible for dental enamel mechanical degradation with fluorosis disease.


Sujet(s)
Apatites , Matériaux biocompatibles , Simulation numérique , Durapatite , Élasticité , Apatites/composition chimique , Matériaux biocompatibles/composition chimique , Durapatite/composition chimique , Modèles moléculaires , Conformation moléculaire , Théorie quantique
7.
Bull Math Biol ; 68(7): 1461-93, 2006 Oct.
Article de Anglais | MEDLINE | ID: mdl-16868854

RÉSUMÉ

This paper presents the derivation, under a minimal set of assumptions, of a general expression for the steady-state fractional modification of an interconvertible protein involved in four different schemes of monocyclic enzyme cascade systems. From this general expression we derive, as particular cases, other, simpler expressions by applying additional assumptions and which have, therefore, a smaller range of validity. Some of these particular expressions coincide with those already obtained in previous contributions on individualised analyses. We discuss the relationships between the kinetic parameters and the concentrations needed for the fulfilment of the additional assumptions. The goodness of the analysis was tested by reference to the shape in the steady-state of the simulated time progress curves obtained by numerical integration.


Sujet(s)
Enzymes/composition chimique , Modèles chimiques , Maturation post-traductionnelle des protéines , Algorithmes , Régulation allostérique , Activation enzymatique , Cinétique , Reproductibilité des résultats
8.
Arch Soc Esp Oftalmol ; 79(6): 273-9, 2004 Jun.
Article de Espagnol | MEDLINE | ID: mdl-15221673

RÉSUMÉ

PURPOSE: To evaluate the accuracy of disk size and cup/disk ratio (C/D) estimation by measuring the vertical diameter and cup/disk ratio at the slit lamp. METHODS: Two hundred and thirty eight eyes of 185 people, 82 glaucomas and 156 normal subjects were included. All underwent slit lamp examination, tonometry, optic nerve photographs, scanning laser tomography (HRT) and standard perimetry (Humphrey). Correlation between slit lamp measurements (vertical diameter and C/D ratio) and HRT parameters was evaluated. RESULTS: There is a significant correlation between the disk diameter measured at the slit lamp and the disk area measured with HRT (Pearson Test, r: 0.52, p<0.001). Additionally, there is significant correlation between the semi-quantitative estimation of C/D ratio at the slit lamp and the C/D area ratio from the HRT (r: 0.83, p<0.001). CONCLUSION: Measuring the vertical diameter and the C/D ratio at the slit lamp is a useful method for estimating the real disk area and C/D ratio. It is highly recommended that disk size be estimated when attempting to interpret clinical findings in the optic nerve head.


Sujet(s)
Nerf optique/anatomie et histologie , Anthropométrie , Femelle , Glaucome/anatomopathologie , Humains , Mâle , Microscopie confocale , Adulte d'âge moyen , Nerf optique/anatomopathologie , Reproductibilité des résultats
9.
Arch. Soc. Esp. Oftalmol ; 79(6): 273-280, jun. 2004. graf, tab
Article de Espagnol | IBECS | ID: ibc-81423

RÉSUMÉ

Objetivo: Evaluar la precisión de la estimación del tamaño de la papila y el índice excavación/papila (E/P) mediante la medición del diámetro vertical y la excavación en la lámpara de hendidura. Método: Se incluyeron 238 ojos de 185 personas, 82 con glaucoma y 156 normales. Todos fueron examinados con lámpara de hendidura, tonometría, fotografías del nervio óptico, tomografía con láser confocal (HRT) y perimetría estándar (Humphrey). Se evaluó la correlación entre el diámetro vertical de la papila y el índice excavación/papila (E/P) medidos en la lámpara de hendidura (lente de 90 o 78 dioptrías) y varios parámetros objetivos obtenidos con el HRT. Resultados: Existe una correlación estadísticamente significativa entre el diámetro papilar estimado mediante biomicroscopía y el área de la papila calculado por el HRT (Test de Pearson, r: 0,52, p<0,001). Asimismo se observó una correlación estadísticamente significativa entre la estimación semicuantitativa del índice E/P obtenido por biomicroscopia y el parámetro área de la excavación/área de la papila calculado por el HRT (r: 0,83; p<0,001). Conclusión: La medida del diámetro vertical y del índice E/P en la lámpara de hendidura es una buena estimación del área de la papila y del cociente área excavación/área de la papila. Se recomienda la valoración del tamaño de la papila a la hora de interpretar los hallazgos clínicos observados en el nervio óptico(AU)


Purpose: To evaluate the accuracy of disk size and cup/disk ratio (C/D) estimation by measuring the vertical diameter and cup/disk ratio at the slit lamp. Methods: Two hundred and thirty eight eyes of 185 people, 82 glaucomas and 156 normal subjects were included. All underwent slit lamp examination, tonometry, optic nerve photographs, scanning laser tomography (HRT) and standard perimetry (Humphrey). Correlation between slit lamp measurements (vertical diameter and C/D ratio) and HRT parameters was evaluated. Results: There is a significant correlation between the disk diameter measured at the slit lamp and the disk area measured with HRT (Pearson Test, r: 0.52, p<0.001). Additionally, there is significant correlation between the semi-quantitative estimation of C/D ratio at the slit lamp and the C/D area ratio from the HRT (r: 0.83, p<0.001). Conclusion: Measuring the vertical diameter and the C/D ratio at the slit lamp is a useful method for estimating the real disk area and C/D ratio. It is highly recommended that disk size be estimated when attempting to interpret clinical findings in the optic nerve head(AU)


Sujet(s)
Humains , Papille optique/ultrastructure , Nerf optique/ultrastructure , Microscopie confocale , Ophtalmoscopie
10.
Immunity ; 15(2): 237-47, 2001 Aug.
Article de Anglais | MEDLINE | ID: mdl-11520459

RÉSUMÉ

Lymphocytes home to lymph nodes, using L-selectin to bind specific ligands on high endothelial venules (HEV). In vitro studies implicate GlcNAc-6-sulfate as an essential posttranslational modification for ligand activity. Here, we show that genetic deletion of HEC-GlcNAc6ST, a sulfotransferase that is highly restricted to HEV, results in the loss of the binding of recombinant L-selectin to the luminal aspect of HEV, elimination of lymphocyte binding in vitro, and markedly reduced in vivo homing. Reactivity with MECA 79, an adhesion-blocking mAb that stains HEV in lymph nodes and vessels in chronic inflammatory sites, is also lost from the luminal aspects of HEV. These results establish a critical role for HEC-GlcNAc6ST in lymphocyte trafficking and suggest it as an important therapeutic target.


Sujet(s)
Chimiotaxie des leucocytes , Sélectine L/métabolisme , Noeuds lymphatiques/cytologie , Système lymphatique/enzymologie , Lymphocytes/cytologie , Sulfotransferases/métabolisme , Animaux , Adhérence cellulaire , Lectines/métabolisme , Ligands , Souris , Souches mutantes de souris , Sulfotransferases/génétique
11.
J Immunol ; 166(2): 1233-40, 2001 Jan 15.
Article de Anglais | MEDLINE | ID: mdl-11145706

RÉSUMÉ

Ag-specific activation of CD4(+) T cells is known to be causative for the cytokine production associated with lung allergy. Chemokine-induced leukocyte recruitment potentially represents a critical early event in Ag-induced lung inflammation. Whether Ag-specific, lung CD4(+) T cell activation is important in lung chemokine production is currently not clear. Using alphabeta-TCR transgenic BALB/c DO11.10 mice, we investigated the ability of Ag-specific CD4(+) T cell activation to induce lung chemokine production and leukocyte recruitment. Within 1 h of exposure of DO11. 10 mice to OVA aerosol, lung mRNA and protein for the neutrophil chemokines KC and macrophage inflammatory protein (MIP)-2 were greatly increased. Accordingly, neutrophils in the airways increased by >50-fold, and KC and MIP-2 proved to be functional because their neutralization significantly reduced airway neutrophilia. CD4(+) T cell activation was critical because CD4(+) but not CD8(+) T cell depletion reduced KC production, which correlated well with the previously observed inhibition of neutrophil influx after CD4(+) T cell depletion. In vitro studies confirmed that OVA-induced KC and MIP-2 production was conditional upon the interaction of CD4(+) T cells with APCs. A likely secondary mediator was TNF-alpha, and a probable source of these chemokines in the lung was alveolar macrophages. Thus, Ag-specific CD4(+) T cell activation in the lung leads to rapid up-regulation of neutrophil chemokines and the recruitment of neutrophils to the site of Ag exposure. This may be a key early event in the pathogenesis of Ag-induced lung inflammation.


Sujet(s)
Lymphocytes T CD4+/immunologie , Lymphocytes T CD4+/métabolisme , Chimiokines CXC/biosynthèse , Déterminants antigéniques des lymphocytes T/immunologie , Protéines et peptides de signalisation intercellulaire , Poumon/immunologie , Poumon/métabolisme , Activation des lymphocytes/immunologie , Régulation positive/immunologie , Administration par inhalation , Administration par voie nasale , Aérosols , Animaux , Présentation d'antigène , Cellules présentatrices d'antigène/immunologie , Cellules présentatrices d'antigène/métabolisme , Liquide de lavage bronchoalvéolaire/composition chimique , Liquide de lavage bronchoalvéolaire/cytologie , Liquide de lavage bronchoalvéolaire/immunologie , Lymphocytes T CD4+/cytologie , Inhibition de la migration cellulaire , Chimiokine CXCL1 , Chimiokine CXCL2 , Chimiokines/biosynthèse , Chimiokines/génétique , Chimiokines/immunologie , Chimiokines CXC/antagonistes et inhibiteurs , Facteurs chimiotactiques/antagonistes et inhibiteurs , Facteurs chimiotactiques/biosynthèse , Facteurs chimiotactiques/génétique , Facteurs chimiotactiques/immunologie , Test ELISA , Femelle , Substances de croissance/biosynthèse , Substances de croissance/génétique , Substances de croissance/immunologie , Sérums immuns/administration et posologie , Sérums immuns/pharmacologie , Poumon/cytologie , Déplétion lymphocytaire , Mâle , Souris , Souris de lignée BALB C , Souris transgéniques , Granulocytes neutrophiles/immunologie , Ovalbumine/administration et posologie , Ovalbumine/antagonistes et inhibiteurs , Ovalbumine/immunologie , Ovalbumine/métabolisme
12.
Rev Esp Cardiol ; 52(6): 415-21, 1999 Jun.
Article de Espagnol | MEDLINE | ID: mdl-10373775

RÉSUMÉ

BACKGROUND AND OBJECTIVES: Intracoronary ultrasound provides a number of advantages in the quantification and characterization of coronary stenoses with regard to contrast angiography. However, previous studies have reported a 3.5 to 11% complication rate, and a 10-30% failure rate in performing this technique. The purpose of the study is to analyze the feasibility of performing intracoronary ultrasound and the incidence of complications associated with the use of contemporary, state of the art equipment. MATERIAL AND METHODS: The feasibility of performing intracoronary ultrasound, analyzed as the percentage of successes and failures in performing the examination was reviewed, as well as the complication rate associated with the technique in all the procedures carried out between July 1, 1994 and February 29, 1996 in which intravascular ultrasound was attempted. Complications were categorized as related, non-related and uncertainly related to the ultrasound study. RESULTS: 239 vessels were studied with intravascular ultrasound in 209 procedures (74% interventional) performed on 139 patients. Ultrasound examination was feasible in all the diagnostic studies and in 96% of the interventional procedures. The major and minor procedural complication rate was 2.4 and 10.5% respectively. No major complication was related to the ultrasound examination. Three patients experienced minor complications (1.4%) related to the ultrasound study. All three complications occurred in baseline studies during interventional procedures. CONCLUSIONS: Intracoronary ultrasound is feasible and safe in the vast majority of the procedures. Improvements in smaller catheter size and design and larger operator expertise have significantly reduced the complication rate, particularly the most frequent coronary spasm so far. Complications are associated with baseline studies during interventional procedures and with less operator expertise.


Sujet(s)
Vaisseaux coronaires/imagerie diagnostique , Échographie interventionnelle , Sujet âgé , Maladie coronarienne/imagerie diagnostique , Femelle , Humains , Mâle , Adulte d'âge moyen , Études rétrospectives , Échographie interventionnelle/effets indésirables , Échographie interventionnelle/instrumentation
13.
Immunity ; 10(4): 421-9, 1999 Apr.
Article de Anglais | MEDLINE | ID: mdl-10229185

RÉSUMÉ

IkappaB kinase-alpha and -beta (IKK-alpha and IKK-beta), the catalytic subunits of the IKK complex, phosphorylate IkappaB proteins on specific serine residues, thus targeting IkappaB for degradation and activating the transcription factor NF-kappaB. To elucidate the in vivo function of IKK-beta, we generated IKK-beta-deficient mice. The homozygous mouse embryo dies at approximately 14.5 days of gestation due to liver degeneration and apoptosis. IKK-beta-deficient embryonic fibroblasts have both reduced basal NF-kappaB activity and impaired cytokine-induced NF-kappaB activation. Similarly, basal and cytokine-inducible kinase activities of the IKK complex are greatly reduced in IKK-beta-deficient cells. These results indicate that IKK-beta is crucial for liver development and regulation of NF-kappaB activity and that IKK-alpha can only partially compensate for the loss of IKK-beta.


Sujet(s)
Mort foetale/immunologie , Foie/embryologie , Foie/anatomopathologie , Mitogen-Activated Protein Kinases , Facteur de transcription NF-kappa B/métabolisme , Protein-Serine-Threonine Kinases/déficit , Protein-Serine-Threonine Kinases/génétique , Animaux , Calcium-Calmodulin-Dependent Protein Kinases/génétique , Calcium-Calmodulin-Dependent Protein Kinases/métabolisme , Lignée cellulaire , Croisements génétiques , Activation enzymatique/génétique , Activation enzymatique/immunologie , Femelle , Mort foetale/enzymologie , Mort foetale/génétique , Humains , I-kappa B Kinase , Interleukine-6/biosynthèse , JNK Mitogen-Activated Protein Kinases , Mâle , Souris , Souris de lignée C57BL , Souris knockout , Transfection/immunologie , Facteur de nécrose tumorale alpha/biosynthèse , Facteur de nécrose tumorale alpha/pharmacologie , Facteur de nécrose tumorale alpha/physiologie
15.
IEEE Trans Biomed Eng ; 45(6): 746-53, 1998 Jun.
Article de Anglais | MEDLINE | ID: mdl-9609939

RÉSUMÉ

A new method is presented for computing the electric lead field of a realistic head shape model which has piecewise homogeneous conductivity. The basic formulae are derived using the well-known reciprocity theorem. Previously described methods are also based upon this theorem, but these first calculate the electric potential inside the head by a scalar boundary element method (BEM), and then approximate the ohmic current density by some sort of gradient. In contrast, this paper proposes the direct evaluation of the ohmic current density by discretizing the vector Green's second identity which leads to a vector version of BEM. This approach also allows the derivation of the same equations for the three concentric spheres model as obtained by Rush and Driscoll [8]. The results of simulations on a spherical head model indicate that the use of a vector BEM leads to an improvement of accuracy in the computation of the ohmic current density with respect to those reported previously, in term of different measures of error.


Sujet(s)
Conductivité électrique , Tête/anatomie et histologie , Modèles biologiques , Algorithmes , Électrodes , Électroencéphalographie , Modèles neurologiques , Sensibilité et spécificité , Propriétés de surface
17.
J Clin Invest ; 98(2): 529-39, 1996 Jul 15.
Article de Anglais | MEDLINE | ID: mdl-8755666

RÉSUMÉ

Chemokines (pro-inflammatory chemoattractant cytokines) are expressed in pathological conditions of the central nervous system (CNS). Previous studies suggested that the CNS is relatively resistant to leukocyte diapedesis after chemokine injection, leaving their functional role unresolved. The CNS function of N51/KC, a neutrophil-selective chemokine, was addressed by expressing N51/KC under control of the myelin basic protein (MBP) promoter in transgenic (tg) mice (MBP-N51/KC mice). CNS-specific N51/KC expression produced remarkable neutrophil infiltration into perivascular, meningeal, and parenchymal sites, demonstrating that this chemokine exerts the multiple functions in vivo required to recruit leukocytes into the CNS. MBP-N5 1/KC mice represent an incisive model for the molecular dissection of neutrophil entry into the CNS. Unexpectedly, MBP-N51/KC mice developed a neurological syndrome of pronounced postural instability and rigidity at high frequency beginning at 40 days of age, well after peak chemokine expression. 68/182 mice in one tg fine were found dead before one year of age, with prominent neurological symptoms premortem in 26 (38%). Florid microglial activation and blood-brain barrier disruption without dysmyelination were the major neuropathological alterations. Late-onset neurological symptoms in MBP-N51/KC mice may indicate unanticipated consequences of CNS chemokine expression.


Sujet(s)
Chimiokines CXC , Facteurs chimiotactiques/biosynthèse , Cytokines/biosynthèse , Substances de croissance/biosynthèse , Protéines et peptides de signalisation intercellulaire , Maladies du système nerveux/physiopathologie , Névroglie/physiologie , Granulocytes neutrophiles/physiologie , Oligodendroglie/physiologie , Animaux , Astrocytes/anatomopathologie , Séquence nucléotidique , Encéphale/anatomopathologie , Encéphale/physiopathologie , Chimiokine CXCL1 , Chimiokines , Facteurs chimiotactiques/génétique , Cytokines/génétique , Amorces ADN , Femelle , Substances de croissance/génétique , Introns , Mâle , Souris , Souris de lignée C57BL , Souris de lignée DBA , Souris de lignée ICR , Souris transgéniques , Microscopie électronique , Données de séquences moléculaires , Protéine basique de la myéline/biosynthèse , Protéine basique de la myéline/génétique , Maladies du système nerveux/génétique , Maladies du système nerveux/anatomopathologie , Névroglie/anatomopathologie , Granulocytes neutrophiles/anatomopathologie , Granulocytes neutrophiles/ultrastructure , Oligodendroglie/anatomopathologie , Réaction de polymérisation en chaîne , Posture , Régions promotrices (génétique) , Protéines de fusion recombinantes/biosynthèse , Cartographie de restriction
18.
J Immunol ; 155(12): 5769-76, 1995 Dec 15.
Article de Anglais | MEDLINE | ID: mdl-7499865

RÉSUMÉ

Transgenic mice overexpressing the chemokine monocyte chemoattractant protein-1 (MCP-1) in the thymus and central nervous system have a higher number of mononuclear cells in those tissues than do control littermates. In the thymus, there is a modest increase in the number of Mac-1 and F4/80 positive cells, but no apparent change in the number of lymphoid cells. A more pronounced mononuclear infiltrate is detected in transgenic mice expressing MCP-1 in the brain. The vast majority of the recruited cells in the brain are monocytes and macrophages, as defined by light microscopy, and ultrastructural and immunohistochemical criteria. Such cells are found in a perivascular orientation with minimal parenchymal infiltration, possibly as a consequence of the accumulation of MCP-1 in the vessels, as shown by immunohistochemistry. The mononuclear cell infiltrate in the brain can be significantly amplified by LPS treatment, suggesting that the recruitment properties of MCP-1 can be potentiated by additional factors.


Sujet(s)
Chimiokine CCL2/physiologie , Facteurs chimiotactiques/physiologie , Chimiotaxie des leucocytes/physiologie , Macrophages/physiologie , Monocytes/physiologie , Animaux , Séquence nucléotidique , Vaisseaux sanguins/ultrastructure , Encéphale/effets des médicaments et des substances chimiques , Encéphale/ultrastructure , Lipopolysaccharides , Souris , Souris transgéniques , Données de séquences moléculaires , Thymus (glande)/effets des médicaments et des substances chimiques , Thymus (glande)/ultrastructure
19.
Toxicol Appl Pharmacol ; 133(1): 130-8, 1995 Jul.
Article de Anglais | MEDLINE | ID: mdl-7541169

RÉSUMÉ

One-week-old larvae of the mollusc Crassostrea virginica, an oyster, were exposed to Cd concentrations ranging from the control with no added Cd to 0.2 microM CdCl2 for 24 hr. Concentration-dependent increases in total cadmium accumulation, cytosolic and metallothionein-bound Cd concentrations, and levels of the MT mRNA were detectable over this range of exposure concentrations. Increases in these measures were apparent at the lowest exposure concentration of 0.005 microM, with dramatic increases observed between 0.04 and 0.2 microM Cd. Although the concentrations of MT-bound Cd increased, the fraction of total Cd that was bound to MTs declined in larvae treated with 0.04 and 0.2 microM Cd, presumably due to the inability of MT biosynthesis to keep up with the higher rates of Cd uptake at the higher concentrations. This decreased effectiveness of MTs in sequestering Cd in relation to the total Cd load and the associated increase in the nonthionein Cd fraction at these higher treatment conditions coincided with a decline in the RNA to DNA ratio and an increase in a nonacetylated variant of the MT. The former is indicative of an inhibition of larval metabolism and growth. The latter is an unexpected form for this MT and is believed to signify disruption of normal cotranslational modification of the N-terminal amino acid sequence.


Sujet(s)
Cadmium/toxicité , ADN/analyse , Métallothionéine/biosynthèse , Mollusca/effets des médicaments et des substances chimiques , ARN/analyse , Animaux , Relation dose-effet des médicaments , Métallothionéine/génétique , Mollusca/physiologie , ARN messager/analyse
20.
J Exp Med ; 180(6): 2039-48, 1994 Dec 01.
Article de Anglais | MEDLINE | ID: mdl-7964481

RÉSUMÉ

Transgenic mice expressing the chemokine N51/KC in thymus, skin, and tongue showed a marked infiltration of a single class of inflammatory cells (neutrophils) in the sites of transgene expression. In the thymus, neutrophils were most numerous in the cortex and juxta-medullary regions, often forming aggregates or clusters. A similar, but less intense, neutrophilic infiltrate occurred in close proximity to the epidermal basal layer of the tongue and skin. No morphologic evidence of injury was observed in the thymus, skin, or tongue of these transgenic mice, indicating that N51/KC expression induces recruitment but not inflammatory activation of neutrophils. The lack of activation in the thymus resulted in a large senescent neutrophilic population that was phagocytosed by thymic macrophages and epithelial-reticular cells. These results indicate that N51/KC is a neutrophil chemoattractant in vivo and establish these transgenic mice as effective models to study the phenomena of recruitment and clearance of neutrophils, events that are critical for the initiation and resolution of the inflammatory response.


Sujet(s)
Chimiokines CXC , Facteurs chimiotactiques/biosynthèse , Expression des gènes , Substances de croissance/biosynthèse , Protéines et peptides de signalisation intercellulaire , Granulocytes neutrophiles/métabolisme , Peau/métabolisme , Thymus (glande)/métabolisme , Vieillissement/métabolisme , Animaux , Séquence nucléotidique , Chimiokine CXCL1 , Hormone de croissance/biosynthèse , Hormone de croissance/génétique , Humains , Inflammation/physiopathologie , Souris , Souris de lignée C57BL , Souris de lignée DBA , Souris transgéniques , Microscopie électronique , Données de séquences moléculaires , Granulocytes neutrophiles/physiologie , Oligodésoxyribonucléotides , Thymus (glande)/croissance et développement , Thymus (glande)/ultrastructure , Langue/métabolisme
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