Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 254
Filter
1.
Eur Ann Otorhinolaryngol Head Neck Dis ; 139(1): 21-27, 2022 Jan.
Article in English | MEDLINE | ID: mdl-34140263

ABSTRACT

OBJECTIVES: This document presents the fundamentals of speech audiometry in noise, general requirements for implementation and criteria for choice among the tests available in French according to the health-professional's needs. MATERIAL AND METHODS: The recommendations are based on a systematic analysis of the literature carried out by a multidisciplinary group of doctors, audiologists and audioprosthetists from all over France. They are graded A, B, C or expert opinion according to decreasing level of scientific evidence. RESULTS: Eight tests of speech audiometry in noise can be used in France. CONCLUSION: To be complete, evaluation of hearing status requires testing understanding of speech in noise. The examination must begin with a minimum of two measurements familiarizing the subject with the test procedure. For initial diagnosis, adaptive procedures establishing the 50% speech reception threshold (SRT50) in noise are to be preferred in order to obtain a rapid and standardized measurement of perception of speech in noise. When the aim is to measure real-life speech comprehension, tests based on sentences, cocktail-party noise and free-field stimulation are to be preferred. Prosthetic gain is evaluated exclusively in free field. This is the only way to evaluate the contribution of binaurality and to measure perception in noise in an environment as close as possible to real life. In order to avoid acoustic interference in free field, at least five loudspeakers should be used, in particular for evaluating the effectiveness of directional microphones, CROS devices enabling sounds picked up in the damaged ear to be rerouted to the functional ear, or bimodal fitting (i.e., when hearing is enabled by two modalities: for example, hearing aid for one ear, cochlear implant for the other).


Subject(s)
Audiology , Cochlear Implants , Hearing Aids , Otolaryngology , Speech Perception , Adult , Humans , Speech
2.
Moulineaux; European Annals of Otorhinolaryngology, Head and Neck Diseases; Jun. 14, 2021.
Non-conventional in English | BIGG - GRADE guidelines | ID: biblio-1291637

ABSTRACT

This document presents the fundamentals of speech audiometry in noise, general requirements for implementation and criteria for choice among the tests available in French according to the health-professional's needs. The recommendations are based on a systematic analysis of the literature carried out by a multidisciplinary group of doctors, audiologists and audioprosthetists from all over France. They are graded A, B, C or expert opinion according to decreasing level of scientific evidence. Eight tests of speech audiometry in noise can be used in France. To be complete, evaluation of hearing status requires testing understanding of speech in noise. The examination must begin with a minimum of two measurements familiarizing the subject with the test procedure. For initial diagnosis, adaptive procedures establishing the 50% speech reception threshold (SRT50) in noise are to be preferred in order to obtain a rapid and standardized measurement of perception of speech in noise. When the aim is to measure real-life speech comprehension, tests based on sentences, cocktail-party noise and free-field stimulation are to be preferred. Prosthetic gain is evaluated exclusively in free field. This is the only way to evaluate the contribution of binaurality and to measure perception in noise in an environment as close as possible to real life. In order to avoid acoustic interference in free field, at least five loudspeakers should be used, in particular for evaluating the effectiveness of directional microphones, CROS devices enabling sounds picked up in the damaged ear to be rerouted to the functional ear, or bimodal fitting (i.e., when hearing is enabled by two modalities: for example, hearing aid for one ear, cochlear implant for the other).


Subject(s)
Humans , Audiometry, Speech/methods , Hearing Loss/diagnosis , France
3.
Transl Psychiatry ; 7(6): e1154, 2017 06 20.
Article in English | MEDLINE | ID: mdl-28632203

ABSTRACT

Early identification of Alzheimer's disease (AD) risk factors would aid development of interventions to delay the onset of dementia, but current biomarkers are invasive and/or costly to assess. Validated plasma biomarkers would circumvent these challenges. We previously identified the kinase DYRK1A in plasma. To validate DYRK1A as a biomarker for AD diagnosis, we assessed the levels of DYRK1A and the related markers brain-derived neurotrophic factor (BDNF) and homocysteine in two unrelated AD patient cohorts with age-matched controls. Receiver-operating characteristic curves and logistic regression analyses showed that combined assessment of DYRK1A, BDNF and homocysteine has a sensitivity of 0.952, a specificity of 0.889 and an accuracy of 0.933 in testing for AD. The blood levels of these markers provide a diagnosis assessment profile. Combined assessment of these three markers outperforms most of the previous markers and could become a useful substitute to the current panel of AD biomarkers. These results associate a decreased level of DYRK1A with AD and challenge the use of DYRK1A inhibitors in peripheral tissues as treatment. These measures will be useful for diagnosis purposes.


Subject(s)
Alzheimer Disease/blood , Brain-Derived Neurotrophic Factor/blood , Homocysteine/blood , Protein Serine-Threonine Kinases/blood , Protein-Tyrosine Kinases/blood , Aged , Alzheimer Disease/diagnosis , Alzheimer Disease/immunology , Animals , Antibodies, Monoclonal/metabolism , Antibodies, Monoclonal/pharmacology , Biomarkers/blood , Female , Humans , Male , Mice, Inbred C57BL , Mice, Transgenic , Middle Aged , Protein Serine-Threonine Kinases/immunology , Protein-Tyrosine Kinases/immunology , ROC Curve , Dyrk Kinases
4.
J Fish Biol ; 90(4): 1321-1337, 2017 Apr.
Article in English | MEDLINE | ID: mdl-27976379

ABSTRACT

The silky shark Carcharhinus falciformis is commonly associated with floating objects, including fish aggregating devices (FADs), in the Indian Ocean. While the motives for this associative behaviour are unclear, it does make them vulnerable to capture in the tuna purse seine fishery that makes extensive use of FADs. Here, the diet of 323 C. falciformis, caught at FADs in the Indian Ocean, was investigated to test the hypothesis that trophic benefits explain the associative behaviour. A high proportion of stomachs with fresh contents (57%) suggested that extensive feeding activity occurred while associated with FADs. Multiple dietary indices showed that typical non-associative prey types dominated, but were supplemented with fishes typically found at FADs. While the trophic benefits of FAD association may be substantial, our results suggest that associative behaviour is not driven solely by feeding.


Subject(s)
Feeding Behavior/physiology , Sharks/physiology , Animals , Conservation of Natural Resources , Environmental Monitoring , Indian Ocean , Tuna
5.
Adv Mar Biol ; 74: 199-344, 2016.
Article in English | MEDLINE | ID: mdl-27573052

ABSTRACT

Tunas are highly specialized predators that have evolved numerous adaptations for a lifestyle that requires large amounts of energy consumption. Here we review our understanding of the bioenergetics and feeding dynamics of tunas on a global scale, with an emphasis on yellowfin, bigeye, skipjack, albacore, and Atlantic bluefin tunas. Food consumption balances bioenergetics expenditures for respiration, growth (including gonad production), specific dynamic action, egestion, and excretion. Tunas feed across the micronekton and some large zooplankton. Some tunas appear to time their life history to take advantage of ephemeral aggregations of crustacean, fish, and molluscan prey. Ontogenetic and spatial diet differences are substantial, and significant interdecadal changes in prey composition have been observed. Diet shifts from larger to smaller prey taxa highlight ecosystem-wide changes in prey availability and diversity and provide implications for changing bioenergetics requirements into the future. Where tunas overlap, we show evidence of niche separation between them; resources are divided largely by differences in diet percentages and size ranges of prey taxa. The lack of long-term data limits the ability to predict impacts of climate change on tuna feeding behaviour. We note the need for systematic collection of feeding data as part of routine monitoring of these species, and we highlight the advantages of using biochemical techniques for broad-scale analyses of trophic relations. We support the continued development of ecosystem models, which all too often lack the regional-specific trophic data needed to adequately investigate climate and fishing impacts.


Subject(s)
Diet/veterinary , Ecology , Energy Metabolism , Tuna/physiology , Animals , Eating , Energy Metabolism/physiology , Feeding Behavior , Fisheries/economics , Models, Biological , Oceans and Seas , Reproduction/physiology , Tuna/metabolism
6.
Environ Res ; 148: 196-206, 2016 07.
Article in English | MEDLINE | ID: mdl-27084988

ABSTRACT

The contamination of albacore tuna (Thunnus alalunga) by Persistent Organic Pollutants (POPs), namely polychlorinated biphenyls (PCBs) and dichlorodiphenyl-trichloroethane (DDT), was investigated in individuals collected from Reunion Island (RI) and South Africa's (SA) southern coastlines in 2013, in relation to biological parameters and feeding ecology. The results showed lower PCB and DDT concentrations than those previously reported in various tuna species worldwide. A predominance of DDTs over PCBs was revealed, reflecting continuing inputs of DDT. Tuna collected from SA exhibited higher contamination levels than those from RI, related to higher dietary inputs and higher total lipid content. Greater variability in contamination levels and profiles was identified in tuna from RI, explained by a higher diversity of prey and more individualistic foraging behaviour. PCB and DDT contamination levels and profiles varied significantly in tuna from the two investigated areas, probably reflecting exposure to different sources of contamination.


Subject(s)
DDT/analysis , Polychlorinated Biphenyls/analysis , Tuna/metabolism , Water Pollutants, Chemical/analysis , Animals , Body Size , Environmental Monitoring , Female , Food Chain , Gastrointestinal Contents/chemistry , Gonads/growth & development , Indian Ocean , Lipid Metabolism , Liver/growth & development , Male , Muscle, Skeletal/chemistry , Organ Size , South Africa
7.
Transbound Emerg Dis ; 63(4): 379-88, 2016 Aug.
Article in English | MEDLINE | ID: mdl-25430732

ABSTRACT

The performance of Whatman 3-MM filter papers for the collection, drying, shipment and long-term storage of blood at ambient temperature, and for the detection of African swine fever virus and antibodies was assessed. Conventional and real-time PCR, viral isolation and antibody detection by ELISA were performed on paired samples (blood/tissue versus dried-blood 3-MM filter papers) collected from experimentally infected pigs and from farm pigs in Madagascar and Côte d'Ivoire. 3-MM filter papers were used directly in the conventional and real-time PCR without previous extraction of nucleic acids. Tests that performed better with 3-MM filter papers were in descending order: virus isolation, real-time UPL PCR and conventional PCR. The analytical sensitivity of real-time UPL PCR on filter papers was similar to conventional testing (virus isolation or conventional PCR) on organs or blood. In addition, blood-dried filter papers were tested in ELISA for antibody detection and the observed sensitivity was very close to conventional detection on serum samples and gave comparable results. Filter papers were stored up to 9 months at 20-25°C and for 2 months at 37°C without significant loss of sensitivity for virus genome detection. All tests on 3-MM filter papers had 100% specificity compared to the gold standards. Whatman 3-MM filter papers have the advantage of being cheap and of preserving virus viability for future virus isolation and characterization. In this study, Whatman 3-MM filter papers proved to be a suitable support for the collection, storage and use of blood in remote areas of tropical countries without the need for a cold chain and thus provide new possibilities for antibody testing and virus isolation.


Subject(s)
African Swine Fever/diagnosis , Blood Specimen Collection/instrumentation , Tropical Climate , African Swine Fever Virus/genetics , African Swine Fever Virus/isolation & purification , Animals , Enzyme-Linked Immunosorbent Assay , Madagascar , Real-Time Polymerase Chain Reaction , Swine
8.
Transl Psychiatry ; 5: e595, 2015 Jul 07.
Article in English | MEDLINE | ID: mdl-26151923

ABSTRACT

Identification of blood-based biomarkers of Alzheimer's disease (AD) remains a challenge. Neuropathological studies have identified enlarged endosomes in post-mortem brains as the earliest cellular change associated to AD. Here the presence of enlarged endosomes was investigated in peripheral blood mononuclear cells from 48 biologically defined AD patients (25 with mild cognitive impairment and 23 with dementia (AD-D)), and 23 age-matched healthy controls using immunocytochemistry and confocal microscopy. The volume and number of endosomes were not significantly different between AD and controls. However, the percentage of cells containing enlarged endosomes was significantly higher in the AD-D group as compared with controls. Furthermore, endosomal volumes significantly correlated to [C(11)]PiB cortical index measured by positron emission tomography in the AD group, independently of the APOE genotype, but not to the levels of amyloid-beta, tau and phosphorylated tau measured in the cerebrospinal fluid. Importantly, we confirmed the presence of enlarged endosomes in fibroblasts from six unrelated AD-D patients as compared with five cognitively normal controls. This study is the first, to our knowledge, to report morphological alterations of the endosomal compartment in peripheral cells from AD patients correlated to amyloid load that will now be evaluated as a possible biomarker.


Subject(s)
Alzheimer Disease/pathology , Endosomes/pathology , Fibroblasts/pathology , Leukocytes, Mononuclear/physiology , Aged , Aged, 80 and over , Alzheimer Disease/blood , Alzheimer Disease/diagnosis , Amyloid beta-Peptides/cerebrospinal fluid , Apolipoproteins E/genetics , Biomarkers/blood , Biomarkers/cerebrospinal fluid , Biomarkers/metabolism , Case-Control Studies , Cognitive Dysfunction/blood , Cognitive Dysfunction/diagnosis , Cognitive Dysfunction/physiopathology , Female , Humans , Male , Microscopy, Confocal , Middle Aged , Neuroimaging , Positron-Emission Tomography , tau Proteins/cerebrospinal fluid
9.
Vaccine ; 33(21): 2493-9, 2015 May 15.
Article in English | MEDLINE | ID: mdl-25820061

ABSTRACT

Some vaccination strategies have shown good results in reducing the clinical outcomes of PRRS. Nevertheless the effect of vaccines on viral transmission is poorly described, so we aimed to fill this gap with the present study. Twelve Specific Pathogen Free (SPF) piglets, vaccinated against PRRSv at 3 weeks of age (Porcilis PRRS ID(®), MSD), were inoculated at 31 days post-vaccination with a heterologous genogroup 1.1 strain, and put in contact with 12 vaccinated piglets during 49 days. The same protocol was carried out simultaneously with SPF non-vaccinated piglets. Piglets were monitored individually for clinical symptoms on a daily basis and individual blood samples were taken twice a week. In inoculated piglets, the genome viral load specific to the inoculated strain was reduced and viraemia shortened in vaccinated piglets (28 days versus 38 days in non vaccinated piglets). In contact pigs, the challenge strain was detected in the serum of only one vaccinated piglet whereas it was detected in all contact non-vaccinated piglets. Transmission parameters were estimated by a Bayesian analysis of transmission data in the two groups. The estimated transmission rate was 10-times lower in vaccinated than in non-vaccinated piglets and the duration of infectiousness was reduced, leading to a reproduction ratio R significantly lower (0.30 [0.05-0.96] versus 5.42 [2.94-9.04] in non vaccinated piglets). Hence, in our experimental conditions, vaccination was able to decrease considerably PRRSv spread. A complementary evaluation in field conditions would be required to identify circumstances associated with infection control failures that can be observed in pig farms.


Subject(s)
Disease Transmission, Infectious/prevention & control , Porcine Reproductive and Respiratory Syndrome/prevention & control , Porcine respiratory and reproductive syndrome virus/immunology , Viral Vaccines/immunology , Animals , Porcine Reproductive and Respiratory Syndrome/transmission , Porcine respiratory and reproductive syndrome virus/isolation & purification , Swine , Vaccines, Attenuated/administration & dosage , Vaccines, Attenuated/immunology , Viral Load , Viral Vaccines/administration & dosage , Viremia/prevention & control
10.
Transl Psychiatry ; 4: e425, 2014 Aug 12.
Article in English | MEDLINE | ID: mdl-25116835

ABSTRACT

To determine whether apparent involvement of DYRK1A in Alzheimer's disease (AD) pathology makes it a candidate plasma biomarker for diagnosis, we developed a method to quantify plasma DYRK1A by immunoblot in transgenic mouse models having different gene dosages of Dyrk1a, and, consequently, different relative protein expression. Then, we measured plasma DYRK1A levels in 26 patients with biologically confirmed AD and 25 controls (negative amyloid imaging available on 13). DYRK1A was detected in transgenic mouse brain and plasma samples, and relative levels of DYRK1A correlated with the gene copy number. In plasma from AD patients, DYRK1A levels were significantly lower compared with controls (P<0.0001). Results were similar when we compared AD patients with the subgroup of controls confirmed by negative amyloid imaging. In a subgroup of patients with early AD (CDR=0.5), lower DYRK1A expression was confirmed. In contrast, no difference was found in levels of DYRK1B, the closest relative of DYRK1A, between AD patients and controls. Further, AD patients exhibited a positive correlation between plasma DYRK1A levels and cerebrospinal fluid tau and phosphorylated-tau proteins, but no correlation with amyloid-ß42 levels and Pittsburgh compound B cortical binding. DYRK1A levels detected in lymphoblastoid cell lines from AD patients were also lower when compared with cells from age-matched controls. These findings suggest that reduced DYRK1A expression might be a novel plasma risk factor for AD.


Subject(s)
Alzheimer Disease/blood , Alzheimer Disease/genetics , Biomarkers/blood , Genetic Markers/genetics , Protein Serine-Threonine Kinases/blood , Protein Serine-Threonine Kinases/genetics , Protein-Tyrosine Kinases/blood , Protein-Tyrosine Kinases/genetics , Aged , Alzheimer Disease/diagnosis , Animals , Brain/metabolism , Brain/pathology , Disease Models, Animal , Female , Genetic Association Studies , Humans , Male , Mice , Mice, Inbred C57BL , Mice, Transgenic , Middle Aged , Positron-Emission Tomography , Predictive Value of Tests , Dyrk Kinases
11.
Res Vet Sci ; 96(2): 389-95, 2014 Apr.
Article in English | MEDLINE | ID: mdl-24530018

ABSTRACT

CP7_E2alf is a promising marker vaccine candidate against classical swine fever (CSF). To better understand the mechanisms of protection, cytokine and isotype-specific antibody profiles were investigated in CP7_E2alf vaccinated pigs before and after challenge with the highly virulent CSFV strain "Koslov" at 14 days or 6 months post-vaccination. The interference of vaccination with CSFV pathogeny-related cytokine responses, previously described following a moderately virulent challenge, was confirmed. However, the levels of additional cytokines, TNF-α and IL-6, were significantly attenuated by vaccination following highly virulent challenge. This vaccine interference with cytokine response was not dependent on the immunization route or the consequence of competition between vaccine and challenge strain. Interestingly, IFN-γ enhancement and persistent high IgG2 levels suggested an important role of cell-mediated immunity in long-term protection against CSFV induced by CP7_E2alf vaccination. IgA production also revealed a stimulation of mucosal immunity, especially after oral administration of the vaccine.


Subject(s)
Classical Swine Fever Virus/immunology , Classical Swine Fever/immunology , Cytokines/blood , Immunoglobulin Isotypes/blood , Vaccination/veterinary , Viral Vaccines/immunology , Administration, Oral , Animals , Classical Swine Fever/prevention & control , Classical Swine Fever/virology , Enzyme-Linked Immunosorbent Assay/veterinary , Statistics, Nonparametric , Swine , Vaccination/methods , Vaccination/standards , Vaccines, Attenuated/administration & dosage , Vaccines, Attenuated/immunology
12.
Adv Pharmacol Sci ; 2011: 153218, 2011.
Article in English | MEDLINE | ID: mdl-22028705

ABSTRACT

Decrease of GABAergic transmission has been proposed to improve memory functions. Indeed, inverse agonists selective for α5 GABA-A-benzodiazepine receptors (α5IA) have promnesiant activity. Interestingly, we have recently shown that α5IA can rescue cognitive deficits in Ts65Dn mice, a Down syndrome mouse model with altered GABAergic transmission. Here, we studied the impact of chronic treatment with α5IA on gene expression in the hippocampus of Ts65Dn and control euploid mice after being trained in the Morris water maze task. In euploid mice, chronic treatment with α5IA increased IEGs expression, particularly of c-Fos and Arc genes. In Ts65Dn mice, deficits of IEGs activation were completely rescued after treatment with α5IA. In addition, normalization of Sod1 overexpression in Ts65Dn mice after α5IA treatment was observed. IEG expression regulation after α5IA treatment following behavioral stimulation could be a contributing factor for both the general promnesiant activity of α5IA and its rescuing effect in Ts65Dn mice alongside signaling cascades that are critical for memory consolidation and cognition.

13.
J Psychopharmacol ; 25(8): 1030-42, 2011 Aug.
Article in English | MEDLINE | ID: mdl-21693554

ABSTRACT

An imbalance between inhibitory and excitatory neurotransmission has been proposed to contribute to altered brain function in individuals with Down syndrome (DS). Gamma-aminobutyric acid (GABA) is the major inhibitory neurotransmitter in the central nervous system and accordingly treatment with GABA-A antagonists can efficiently restore cognitive functions of Ts65Dn mice, a genetic model for DS. However, GABA-A antagonists are also convulsant which preclude their use for therapeutic intervention in DS individuals. Here, we have evaluated safer strategies to release GABAergic inhibition using a GABA-A-benzodiazepine receptor inverse agonist selective for the α5-subtype (α5IA). We demonstrate that α5IA restores learning and memory functions of Ts65Dn mice in the novel-object recognition and in the Morris water maze tasks. Furthermore, we show that following behavioural stimulation, α5IA enhances learning-evoked immediate early gene products in specific brain regions involved in cognition. Importantly, acute and chronic treatments with α5IA do not induce any convulsant or anxiogenic effects that are associated with GABA-A antagonists or non-selective inverse agonists of the GABA-A-benzodiazepine receptors. Finally, chronic treatment with α5IA did not induce histological alterations in the brain, liver and kidney of mice. Our results suggest that non-convulsant α5-selective GABA-A inverse agonists could improve learning and memory deficits in DS individuals.


Subject(s)
Down Syndrome/drug therapy , GABA-A Receptor Agonists/pharmacology , Phthalazines/pharmacology , Receptors, GABA-A/drug effects , Triazoles/pharmacology , Animals , Brain/drug effects , Brain/metabolism , Cognition Disorders/drug therapy , Cognition Disorders/etiology , Disease Models, Animal , Down Syndrome/physiopathology , Drug Delivery Systems , Drug Inverse Agonism , GABA-A Receptor Agonists/administration & dosage , GABA-A Receptor Agonists/toxicity , Male , Maze Learning/drug effects , Memory/drug effects , Mice , Mice, Inbred C3H , Mice, Inbred C57BL , Phthalazines/administration & dosage , Phthalazines/toxicity , Receptors, GABA-A/metabolism , Triazoles/administration & dosage , Triazoles/toxicity
14.
Br J Pharmacol ; 162(2): 464-79, 2011 Jan.
Article in English | MEDLINE | ID: mdl-20955368

ABSTRACT

BACKGROUND AND PURPOSE: The 1-O-octadecyl-2-O-methyl-sn-glycero-3-phosphocholine (edelfosine) is an ether-linked phospholipid with promising anti-cancer properties but some side effects that preclude its full clinical therapeutic exploitation. We hypothesized that this lipid could interact with plasma membrane ion channels and modulate their function. EXPERIMENTAL APPROACH: Using cell migration-proliferation assays, patch clamp, spectrofluorimetry and ¹²5I-Apamin binding experiments, we studied the effects of edelfosine on the migration of breast cancer MDA-MB-435s cells, mediated by the small conductance Ca²(+) -activated K(+) channel, SK3/K(Ca)2.3. KEY RESULTS: Edelfosine (1 µM) caused plasma membrane depolarization by substantially inhibiting activity of SK3/K(Ca)2.3 channels, which we had previously demonstrated to play an important role in cancer cell migration. Edelfosine did not inhibit ¹²5I-Apamin binding to this SK(Ca) channel; rather, it reduced the calcium sensitivity of SK3/K(Ca)2.3 channel and dramatically decreased intracellular Ca²(+) concentration, probably by insertion in the plasma membrane, as suggested by proteinase K experiments. Edelfosine reduced cell migration to the same extent as known SK(Ca) channel blockers. In contrast, K+ channel openers prevented edelfosine-induced anti-migratory effects. SK3 protein knockdown decreased cell migration and totally abolished the effect of edelfosine on MDA-MB-435s cell migration. In contrast, transient expression of SK3/K(Ca)2.3 protein in a SK3/K(Ca)2.3-deficient cell line increased cell migration and made these cells responsive to edelfosine. CONCLUSIONS AND IMPLICATIONS: Our data clearly establish edelfosine as an inhibitor of cancer cell migration by acting on SK3/K(Ca)2.3 channels and provide insights into the future development of a new class of migration-targeted, anti-cancer agents.


Subject(s)
Antineoplastic Agents/pharmacology , Breast Neoplasms/drug therapy , Breast Neoplasms/metabolism , Cell Movement/drug effects , Phospholipid Ethers/pharmacology , Small-Conductance Calcium-Activated Potassium Channels/metabolism , Antineoplastic Agents/metabolism , Apamin/metabolism , Calcium/metabolism , Cell Line, Tumor , Cell Membrane/drug effects , Cell Migration Assays , Endopeptidase K/metabolism , Epithelial Cells , Female , HEK293 Cells , Humans , Membrane Potentials/drug effects , Molecular Targeted Therapy , Phospholipid Ethers/metabolism
15.
Cell Death Differ ; 18(1): 99-108, 2011 Jan.
Article in English | MEDLINE | ID: mdl-20577261

ABSTRACT

L-glutamate, the major excitatory neurotransmitter, also has a role in non-neuronal tissues and modulates immune responses. Whether NMDA receptor (NMDAR) signalling is involved in T-cell development is unknown. In this study, we show that mouse thymocytes expressed an array of glutamate receptors, including NMDARs subunits. Sustained calcium (Ca(2+)) signals and caspase-3 activation in thymocytes were induced by interaction with antigen-pulsed dendritic cells (DCs) and were inhibited by NMDAR antagonists MK801 and memantine. NMDARs were transiently activated, triggered the sustained Ca(2+) signal and were corecruited with the PDZ-domain adaptor postsynaptic density (PSD)-95 to thymocyte-DC contact zones. Although T-cell receptor (TCR) activation was sufficient for relocalization of NMDAR and PSD-95 at the contact zone, NMDAR could be activated only in a synaptic context. In these T-DC contacts, thymocyte activation occurred in the absence of exogenous glutamate, indicating that DCs could be a physiological source of glutamate. DCs expressed glutamate, glutamate-specific vesicular glutamate transporters and were capable of fast glutamate release through a Ca(2+)-dependent mechanism. We suggest that glutamate released by DCs could elicit focal responses through NMDAR-signalling in T cells undergoing apoptosis. Thus, synapses between T and DCs could provide a functional platform for coupling TCR activation and NMDAR signalling, which might reflect on T-cell development and modulation of the immune response.


Subject(s)
Calcium Signaling , Calcium/metabolism , Caspase 3/metabolism , Dendritic Cells/immunology , Receptors, N-Methyl-D-Aspartate/metabolism , Thyroid Gland/immunology , Amino Acid Transport System X-AG/metabolism , Animals , Apoptosis , Dendritic Cells/metabolism , Disks Large Homolog 4 Protein , Dizocilpine Maleate/pharmacology , Excitatory Amino Acid Antagonists/pharmacology , Glutamic Acid/metabolism , Glutamic Acid/pharmacology , Guanylate Kinases , Intracellular Signaling Peptides and Proteins/chemistry , Intracellular Signaling Peptides and Proteins/metabolism , Memantine/pharmacology , Membrane Proteins/chemistry , Membrane Proteins/metabolism , Mice , Receptors, N-Methyl-D-Aspartate/antagonists & inhibitors , Thyroid Gland/cytology , Thyroid Gland/metabolism
16.
Rev Sci Tech ; 30(3): 797-807, 2011 Dec.
Article in English | MEDLINE | ID: mdl-22435192

ABSTRACT

Since 2004, the French National Reference Laboratory for classical swine fever (CSF) has conducted an annual proficiency test (PT) to evaluate the ability of local veterinary laboratories to perform real-time polymerase chain reaction (PCR) for CSF virus. The results of five years of testing (2004-2008) are described here. The PT was conducted under blind conditions on 20 samples. The same batch of samples was used for all five years. The number of laboratories that analysed the samples increased from four in 2004 to 13 in 2008. The results of the PT showed the following: cross-contamination between samples and deficiencies in RNA preparation can occur even in experienced laboratories; sample homogeneity should be checked carefully before selection; samples stored at-80 degrees C for several years remain stable; and poor shipment conditions do not damage the samples with regard to detection of CSF virus genome. These results will enable redesign of the panel to improve the overall quality of the PT, which will encourage laboratories to check and improve their PCR procedures and expertise. This is an excellent way to determine laboratory performance.


Subject(s)
Classical Swine Fever Virus/isolation & purification , Classical Swine Fever/diagnosis , Laboratories/standards , Real-Time Polymerase Chain Reaction/veterinary , Veterinary Medicine/standards , Animals , Classical Swine Fever/virology , Classical Swine Fever Virus/genetics , DNA, Complementary/analysis , France , Quality Control , RNA, Viral/genetics , RNA, Viral/isolation & purification , Real-Time Polymerase Chain Reaction/standards , Reproducibility of Results , Sensitivity and Specificity , Spleen/virology , Swine
17.
Vet Microbiol ; 142(1-2): 99-107, 2010 Apr 21.
Article in English | MEDLINE | ID: mdl-19854007

ABSTRACT

Over the last 20 years, oral vaccination implementing a live attenuated vaccine has been experimented in Europe in order to control classical swine fever (CSF) in Wild Boar (Sus scrofa sp.). This has generally led to an enhanced seroprevalence and a decreased viroprevalence at the scale of the whole vaccinated populations, but no quantitative analysis has demonstrated the protective effect of preventive vaccination or intensive baiting. In the present paper we conducted a retrospective analysis at the scale of the municipality, taking into account the local dynamics and possible covariates of infection to test the effect of preventive vaccination and of the baiting effort. To be efficient, vaccination was expected to increase seroprevalence above the level considered as suitable for preventing disease invasion (40-60%) independently of infection, to protect free areas from disease invasion or contribute to control subsequent disease intensity and duration. We also hypothesized that a better baiting effort would be correlated with an improvement of immunisation and disease control. In uninfected municipalities, seroprevalence increased up to 40% after 1 year, i.e., three vaccination campaigns. We observed a significant protective effect of preventive vaccination, especially within municipalities that had been vaccinated at least 1 year before disease emergence and where virus detection did not last more than one quarter. On the other hand, we did not detect a significant effect of the baiting effort on local seroprevalence or disease dynamics, suggesting that the baiting system could be improved. We discuss these results regarding the improvement of management measures and further research perspective.


Subject(s)
Classical Swine Fever Virus/immunology , Classical Swine Fever/prevention & control , Vaccination/veterinary , Viral Vaccines , Animals , Classical Swine Fever/epidemiology , Logistic Models , Male , Seroepidemiologic Studies , Sus scrofa , Swine , Viral Vaccines/immunology
18.
Vet Microbiol ; 139(3-4): 365-8, 2009 Nov 18.
Article in English | MEDLINE | ID: mdl-19592179

ABSTRACT

5-[(4-Bromophenyl)methyl]-2-phenyl-5H-imidazo[4,5-c]pyridine (BPIP) is a representative molecule of a novel class of highly active in vitro inhibitors of the replication of Classical swine fever virus (CSFV). We recently demonstrated in a proof of concept study that the molecule has a marked effect on viral replication in CSFV-infected pigs. Here, the effect of antiviral treatment on virus transmission to untreated sentinel pigs was studied. Therefore, BPIP-treated pigs (n=4), intra-muscularly infected with CSFV, were placed into contact with untreated sentinel pigs (n=4). Efficient transmission of CSFV from four untreated seeder pigs to four untreated sentinels was observed. In contrast, only two out of four sentinel animals in contact with BPIP-treated seeder animals developed a short transient infection, of which one was likely the result of sentinel to sentinel transmission. A significant lower viral genome load was measured in tonsils of sentinels in contact with BPIP-treated seeder animals compared to the positive control group (p=0.015). Although no significant difference (p=0.126) in the time of onset of viraemia could be detected between the groups of contact animals, a tendency towards the reduction of virus transmission was observed. Since sentinel animals were left untreated in this exploratory trial, the study can be regarded as a worst case scenario and gives therefore an underestimation of the potential efficacy of the activity of BPIP on virus transmission.


Subject(s)
Antiviral Agents/therapeutic use , Classical Swine Fever Virus/drug effects , Classical Swine Fever/prevention & control , Classical Swine Fever/transmission , Imidazoles/therapeutic use , Pyridines/therapeutic use , Animals , Classical Swine Fever/virology , Classical Swine Fever Virus/isolation & purification , Palatine Tonsil/virology , Sus scrofa , Viral Load , Viremia/prevention & control , Viremia/transmission , Viremia/virology , Virus Replication/drug effects , Virus Replication/immunology
19.
Int J Pharm ; 373(1-2): 16-23, 2009 May 21.
Article in English | MEDLINE | ID: mdl-19429284

ABSTRACT

We have evaluated the ability of recombinant E2 antigen, as a surfactant free formulation of poly (D,L-lactide-co-glycolide) (PLGA) microspheres, to elicit a systemic immune response after administration by mucosal routes (oral and nasal) in comparison to intramuscular route. The sequence encoding a truncated E2 glycoprotein of the classical swine fever virus (CSFV) was expressed in insect cells following infection with recombinant baculovirus, as a His-tagged recombinant antigen. The recombinant E2 glycoprotein (rE2) antigen was co-encapsulated with rabbit serum albumin (RSA) as a protein stabilizer. rE2/RSA loaded PLGA microspheres, with a mean diameter of 4 microm were obtained by a water in oil in water solvent extraction method (w/o/w). Rabbits were immunized with 10 microg of rE2 formulated in PLGA microspheres administrated by three different routes (oral, nasal and intramuscular). After 60 days, each rabbit in all three groups was challenge with 5 microg of rE2 glycoprotein solution by intradermal administration. Blood samples were collected weekly for 90 days and specific rE2 antigen antibodies measured. This work showed that rE2 antigen loaded microspheres was able to initiate an immune response. The intradermal challenge after nasal and oral administration had a clear boost effect on the systemic immune response. Moreover, the response after nasal administration was more intense and less variable than oral route. In conclusion, these data demonstrate a high potential of rE2 loaded PLGA microspheres for their use as a mucosal subunit vaccine.


Subject(s)
Antigens, Viral/administration & dosage , Classical Swine Fever Virus/immunology , Lactic Acid/chemistry , Microspheres , Polyglycolic Acid/chemistry , Viral Envelope Proteins/administration & dosage , Viral Vaccines/administration & dosage , Administration, Intranasal , Administration, Oral , Animals , Antibody Formation/immunology , Antigens, Viral/immunology , Biological Availability , Immunity, Mucosal/immunology , Immunization, Secondary , Immunoglobulins/blood , Immunoglobulins/immunology , Injections, Intradermal , Injections, Intramuscular , Particle Size , Polylactic Acid-Polyglycolic Acid Copolymer , Rabbits , Recombinant Fusion Proteins/administration & dosage , Recombinant Fusion Proteins/immunology , Recombinant Fusion Proteins/pharmacokinetics , Serum Albumin/chemistry , Serum Albumin/pharmacokinetics , Vaccination , Vaccines, Subunit/administration & dosage , Vaccines, Subunit/immunology , Viral Envelope Proteins/immunology , Viral Envelope Proteins/pharmacokinetics , Viral Vaccines/immunology
20.
Ann Pharm Fr ; 67(2): 127-35, 2009 Mar.
Article in French | MEDLINE | ID: mdl-19298896

ABSTRACT

Alzheimer disease lesions include the abnormal accumulation of two proteins normally present in neurons: tau protein and Abeta peptide. Tau protein aggregates into fibrils in the cell body of neurons (neurofibrillary tangles), in dendrites (neuropil threads) and in degenerating axons that constitute the corona of the senile plaque. Tau pathology progresses in the brain areas in a stereotyped manner and in parallel with the clinical symptoms. Abeta extracellular deposits may be diffuse or focal. The Abeta focal deposit constitutes the core of the senile plaque. Progression of the Abeta lesions, which initially affect the isocortex, then the hippocampus, basal ganglia, various brainstem nuclei and cerebellum, is not directly correlated with symptoms. Mutations involving the genes implicated in Abeta peptide metabolism are responsible for familial Alzheimer disease. Mutations of the tau gene are not associated with Alzheimer disease but with frontotemporal dementia. The link between altered Abeta peptide metabolism and tau pathology has not been fully elucidated. Animal models mimic several aspects of the disease and have contributed to a better understanding of the mechanisms of the lesions.


Subject(s)
Alzheimer Disease/pathology , Brain/pathology , Aged , Alzheimer Disease/etiology , Alzheimer Disease/genetics , Humans , Mental Processes , Neurons/pathology
SELECTION OF CITATIONS
SEARCH DETAIL
...