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1.
Med Vet Entomol ; 31(1): 102-106, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-27775162

RESUMO

The Asian tiger mosquito Stegomyia albopicta (= Aedes albopictus) (Diptera: Culicidae), native to Asian forests, is a nuisance mosquito and is responsible for the transmission of arboviruses of public health importance, such as dengue, chikungunya and Zika viruses. It has colonized parts of all continents, except Antarctica, over the past 30-40 years. However, to date, the only records of S. albopicta in North Africa refer to occasional collections in 2010 and 2014 in Algeria. In early September 2015, S. albopicta larvae and adults were collected in a district of Rabat, Morocco. Morphological identification was confirmed by molecular analysis. This is the first record of this invasive mosquito in Morocco. A national surveillance programme will be implemented in 2016 to establish its geographical distribution in Morocco and to instigate control measures to prevent the establishment of new populations and the transmission of arboviruses.


Assuntos
Aedes/fisiologia , Distribuição Animal , Insetos Vetores/fisiologia , Aedes/crescimento & desenvolvimento , Animais , Feminino , Larva/genética , Larva/fisiologia , Masculino , Marrocos , Saúde Pública
2.
Proc Biol Sci ; 279(1731): 1131-41, 2012 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-21920984

RESUMO

Despite considerable effort for surveillance of wild birds for avian influenza viruses (AIVs), empirical investigations of ecological drivers of AIV prevalence in wild birds are still scarce. Here we used a continental-scale dataset, collected in tropical wetlands of 15 African countries, to test the relative roles of a range of ecological factors on patterns of AIV prevalence in wildfowl. Seasonal and geographical variations in prevalence were positively related to the local density of the wildfowl community and to the wintering period of Eurasian migratory birds in Africa. The predominant influence of wildfowl density with no influence of climatic conditions suggests, in contrast to temperate regions, a predominant role for inter-individual transmission rather than transmission via long-lived virus persisting in the environment. Higher prevalences were found in Anas species than in non-Anas species even when we account for differences in their foraging behaviour (primarily dabbling or not) or their geographical origin (Eurasian or Afro-tropical), suggesting the existence of intrinsic differences between wildfowl taxonomic groups in receptivity to infection. Birds were found infected as often in oropharyngeal as in cloacal samples, but rarely for both types of sample concurrently, indicating that both respiratory and digestive tracts may be important for AIV replication.


Assuntos
Aves/virologia , Influenza Aviária/transmissão , África , Animais , Clima , Suscetibilidade a Doenças/epidemiologia , Suscetibilidade a Doenças/veterinária , Suscetibilidade a Doenças/virologia , Geografia , Influenza Aviária/epidemiologia , Modelos Lineares , Prevalência , Especificidade da Espécie
3.
Avian Dis ; 55(4): 650-8, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22312986

RESUMO

Our survey aimed to investigate avian influenza (AI) and Newcastle disease (ND) prevalence and risk factors in three areas of Mali at risk for occurrence of H5N1 highly pathogenic avian influenza. Blood samples and cloacal and oropharyngeal swabs were collected from 1470 birds between February 2007 and May 2008 and were tested by commercial enzyme-linked immunosorbent assay to detect antibodies and real-time reverse-transcription (rRT)-PCR to detect virus. Risk factors associated with seropositivity or positive rRT-PCR were identified by random effect logistic regression. AI seroprevalence was significantly lower in birds from commercial farms (0%) than in village backyard birds (3.1%). For backyard birds, no individual risk factors (species, age, sex) were identified, but birds in the Mopti area in the Sahelian zone, where millions of wild birds migrate, were more seropositive than in the Sikasso area in the Sudano-Guinean zone (odds ratio [OR] = 2.0, P = 0.051). Among backyard birds nonvaccinated against ND, ND seroprevalence was 58.4%, and the odds of seropositivity was 2.0 higher in chickens than in ducks, 1.7 higher in females than in males, 3.1 higher in adults than in young birds, and 3.0 higher in poultry from the Sikasso area than from the Mopti area (P < 0.01 in all cases). Prevalence established by rRT-PCR was low for both AI virus (1.1%) and ND virus (2.6%) and was associated with no risk factors for AI but was higher in chickens than in ducks (OR = 5.3, P = 0.05) and in the Sikasso area than in the Mopti area (OR = 3.4, P = 0.027) for ND. For AI and ND, prevalence assessed by serology or rRT-PCR varied over time, although seasonal and interannual variation could not be clearly distinguished. The intracluster correlation coefficient for serologic data was low for AI (0.014) and higher for ND (0.222). These results are useful to optimize surveillance and control strategy for notifiable avian diseases in African countries with similar agroecological and resource-limited contexts.


Assuntos
Galinhas , Patos , Virus da Influenza A Subtipo H5N1/isolamento & purificação , Influenza Aviária/epidemiologia , Doença de Newcastle/epidemiologia , Animais , Feminino , Influenza Aviária/virologia , Masculino , Mali/epidemiologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa/veterinária , Fatores de Risco , Testes Sorológicos
4.
Virologie (Montrouge) ; 11(3): 217-229, 2007 Jun 01.
Artigo em Francês | MEDLINE | ID: mdl-37012849

RESUMO

Encephalomyocarditis virus (EMCV) is a cardiovirus of Picornaviridae family. It has a word wide distribution and affects a wide range of domestic and wild animal species mainly rodents, pigs and non-human primates. Depending on the virus strain and the infected host, the virus can induce myocarditis, reproductive failure, diabetes or nervous disorders. The importance of EMCV as a cause of disease in humans is unknown. However, its wide host range and its biological characteristics make this virus a potential zoonotic agent. Furthermore, several direct and indirect arguments, suggest that human infections cannot be discarded. This review summarises the current knowledge on the molecular biology, the pathogenicity and the zoonotic aspects of this virus.

5.
Eur Neuropsychopharmacol ; 7 Suppl 3: S337-40, 1997 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9405960

RESUMO

Alcohol dependence represents a major problem in public health and different animal models of dependence have been developed in rodents with the aim of studying the mechanisms of alcohol abuse. Different ways of animal alcoholisation have been established. They permit a better understanding of which neurotransmitter system is involved in the regulation of alcohol dependence. Considerable attention has been given to the role of serotonin in the control of both alcohol craving and alcohol related pathologies, i.e. anxiety, aggression or memory loss. In conclusion, the use of animal models of alcohol abuse facilitates the understanding of alcohol behavior and permits the development of new therapeutic agents.


Assuntos
Dissuasores de Álcool/uso terapêutico , Alcoolismo/tratamento farmacológico , Alcoolismo/fisiopatologia , Animais , Modelos Animais de Doenças , Etanol/administração & dosagem
6.
Alcohol ; 17(2): 107-12, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10064377

RESUMO

The serotonin (5-hydroxytryptamine: 5-HT) system has been thought to play an important role in several steps of alcohol craving. A number of studies, including our own, have reported that alcohol dependence is associated with dysfunction of 5-HT transmission. Pharmacological and clinical studies have shown that the 5-HT transporter (5-HTT) and the 5-HT1A receptor appear to be candidate loci for the aetiology of alcohol dependence. We have analysed the presence of different 5-HTT and 5-HT1A variants in 104 alcohol-dependent patients and 38 controls for a possible association with alcohol dependence. In alcohol-dependent patients, we found a high frequency of the S allele of 5-HTTLPR (45.5% vs. 29%, chi2 = 6.33, p = 0.0081). No other significant differences were observed between the two populations for other polymorphisms. These results provide, for the first time, preliminary evidence that alcohol abuse disorders are associated with a genetic variant for 5-HT transmission. It might be possible to use this detection of the "S" allele as a clinical tool for pathology diagnosis and to advise recovering alcoholics and it could represent an aid to the prevention of relapse. Therapeutic actions could be envisaged to use this genotyping to help select the best therapeutic strategy.


Assuntos
Alcoolismo/genética , Proteínas de Transporte/genética , Marcadores Genéticos , Glicoproteínas de Membrana/genética , Proteínas de Membrana Transportadoras , Proteínas do Tecido Nervoso , Adulto , Alelos , Análise Mutacional de DNA , Feminino , Frequência do Gene , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Repetições Minissatélites , Polimorfismo de Fragmento de Restrição , Receptores de Serotonina/genética , Receptores 5-HT1 de Serotonina , Proteínas da Membrana Plasmática de Transporte de Serotonina
7.
Vet Rec ; 150(19): 598-601, 2002 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-12036242

RESUMO

In October 2000, bluetongue virus was detected on the French island of Corsica. The disease was also reported in Sardinia, Calabria, Sicily and on the Spanish islands of Majorca and Minorca. This paper describes the use of molecular techniques for a rapid identification and serotype determination of serotype 2 of the virus. The nucleotide sequences of segments 2 and 7 of the genome of the Corsican strain were determined and its phylogenetic relationships are described.


Assuntos
Vírus Bluetongue/genética , DNA Viral/análise , Doenças dos Ovinos/virologia , Animais , Vírus Bluetongue/classificação , Surtos de Doenças , Europa (Continente)/epidemiologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa/veterinária , Análise de Sequência de DNA , Sorotipagem , Ovinos , Doenças dos Ovinos/genética
8.
Arch Virol ; 151(9): 1783-96, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16575480

RESUMO

A recombinant encephalomyocarditis virus (rEMCV2887A-egfp) expressing the enhanced green fluorescent protein (EGFP) was produced. The EGFP gene was inserted in frame within the leader protein coding sequence of a full-length cDNA clone of EMCV. RNA transcripts derived from the recombinant full-length cDNA were synthesized in vitro and transfected into BHK-21 cells. The recombinant transcript RNA remained infectious despite the insertion of EGFP as shown by cytopathic effects on BHK-21 cells and by propagation of the rescued virus. The replication kinetics in BHK-21 cells and the pathogenicity in mice of rEMCV2887A-egfp did not differ significantly from that of the parental virus. The recombinant virus was shown to produce fluorescence in infected cells after at least five passages in BHK-21 cells. However, a decrease of EGFP expression was observed following serial passages, and this was associated with the accumulation of deletion mutations within the EGFP gene. Nevertheless, using EGFP autofluorescence, infected cells were easily detected in the brain of mice infected with the first-passage recombinant virus. These data demonstrate that rEMCV2887A-egfp could be a useful tool to study virus dissemination and pathogenicity when used at low passages.


Assuntos
Vírus da Encefalomiocardite/genética , Vírus da Encefalomiocardite/fisiologia , Proteínas de Fluorescência Verde/biossíntese , Recombinação Genética , Animais , Encéfalo/virologia , Infecções por Cardiovirus/virologia , Linhagem Celular , Cricetinae , Efeito Citopatogênico Viral , Modelos Animais de Doenças , Vírus da Encefalomiocardite/patogenicidade , Citometria de Fluxo , Fluorescência , Proteínas de Fluorescência Verde/genética , Camundongos , Camundongos Endogâmicos BALB C , Microscopia de Fluorescência , Deleção de Sequência , Replicação Viral
9.
Alcohol Clin Exp Res ; 22(4): 802-9, 1998 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9660304

RESUMO

It has been suggested that the anticraving drug, acamprosate, acts via the glutamatergic system, but the exact mechanism of action is still unknown. The aim of this study was to characterize [3H]acamprosate binding and establish whether this showed any relation to sites on the NMDA receptor complex. We found saturable specific binding of [3H]acamprosate to rat brain membranes with a KD of 120 microM and a Bmax of 450 pmol/mg of protein. This acamprosate binding site was sensitive to inhibition by spermidine (IC50: 13.32 +/- 1.1 microM; Hill coefficient = 1.04), and arcaine and glutamate both potentiated the inhibitory effect of spermidine. Acamprosate binding to the acamprosate binding site was also sensitive to inhibition by divalent cations (Ca2+, Mg2+, and Sr2+). Conversely, acamprosate displaced [14C]spermidine binding from rat brain membranes with an IC50 of 645 microM and a Hill coefficient = 1.74. This inhibitory effect of acamprosate was not affected by arcaine, and was associated with a significant reduction in Bmax and binding affinity for spermidine, suggesting an allosteric interaction between acamprosate and a spermidine binding site. These data are consistent with an effect of acamprosate on the NMDA receptor protein complex, and acamprosate was also found to alter binding of [3H]dizocilpine to rat brain membranes. When no agonists were present in vitro (minimal NMDA receptor activation), acamprosate markedly potentiated [3H]dizocilpine binding at concentrations in the 5 to 200 microM range. However, under conditions of maximal receptor activation (100 microM glutamate, 30 microM glycine), acamprosate only inhibited [3H]dizocilpine binding (at concentrations concentrations >100 microM). When these binding studies were performed in the presence of 1 microM spermidine, the enhancing effects of acamprosate on [3H]dizocilpine binding were inhibited. The results show that acamprosate binds to a specific spermidine-sensitive site that modulates the NMDA receptor in a complex way. Together, with data from al Quatari et al. (see next paper), this work suggests that acamprosate acts as "partial co-agonist" at the NMDA receptor, so that low concentrations enhance activation when receptor activity is low, whereas higher concentrations are inhibitory to high levels of receptor activation. This may be relevant to the clinical effects of acamprosate in alcohol-dependent patients during abstinence.


Assuntos
Dissuasores de Álcool/farmacologia , Encéfalo/efeitos dos fármacos , Receptores de N-Metil-D-Aspartato/efeitos dos fármacos , Espermidina/farmacologia , Taurina/análogos & derivados , Acamprosato , Dissuasores de Álcool/farmacocinética , Animais , Técnicas de Cultura , Masculino , Ratos , Ratos Sprague-Dawley , Membranas Sinápticas/efeitos dos fármacos , Taurina/farmacocinética , Taurina/farmacologia
10.
J Gen Virol ; 82(Pt 9): 2199-2204, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11514730

RESUMO

Borna disease virus (BDV) is an enveloped, non-segmented negative-stranded RNA virus which belongs to the Bornaviridae family. BDV is an aetiological agent of encephalitis in horses, sheep and several other vertebrate species. In order to extend our knowledge about the presence of BDV in France, a study based on BDV RNA detection by RT-nested-PCR was done with 196 animal tissues: 171 brain samples collected from different animal species (75 horses, 59 foxes, 31 cattle, 4 dogs, 1 sheep, 1 roe deer) and 25 horse blood samples. An RNA internal standard molecule was constructed and was co-amplified with the test template. This study reports the first detection of BDV RNA in France in 10 brain samples collected from horses, foxes and cattle, and from 14 horse blood samples. Detection of the BDV genome in the brains of six red foxes is the first evidence of BDV infection in this species.


Assuntos
Vírus da Doença de Borna/genética , Raposas/virologia , RNA Viral/análise , Animais , Encéfalo/virologia , Bovinos , Cervos , Cães , Cavalos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Ovinos
11.
Artigo em Inglês | MEDLINE | ID: mdl-14535928

RESUMO

In order to study the safety and the immunogenicity of the South African vaccine against the serotype 2 bluetongue virus, two groups of seven sheep were vaccinated with the vaccine used in the French island of Corsica. Vaccinated and non-vaccinated sheep were observed clinically and their rectal temperatures were recorded daily. The serological response in vaccinated animals confirmed the immunogenicity of the vaccine. Post-vaccinal viraemia was investigated and the vaccine genome was detected by reverse transcription polymerase chain reaction (RT-PCR). No viraemia was observed at post-vaccination days 4, 7 and 11 but the vaccine strain of virus was detected by RT-PCR throughout the experiment. The thermostability of the vaccine was also evaluated. The vaccine titre strongly decreased at temperatures higher than 35 degrees C.


Assuntos
Vírus Bluetongue/classificação , Vírus Bluetongue/imunologia , Bluetongue/prevenção & controle , Genoma Viral , Vacinas Virais , Animais , Bluetongue/sangue , Vírus Bluetongue/genética , Temperatura Corporal , Ensaio de Imunoadsorção Enzimática/veterinária , Reação em Cadeia da Polimerase Via Transcriptase Reversa/veterinária , Sorotipagem , Ovinos , Vacinação/veterinária , Viremia/veterinária
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