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1.
Vet Res ; 49(1): 84, 2018 08 30.
Artigo em Inglês | MEDLINE | ID: mdl-30165897

RESUMO

The original article [1] contained an error in the Author details paragraph. "5Neglected Zoonotic Diseases, World Health Organization, Geneva, Switzerland" should be replaced by "5Le Grand-Saconnex, Switzerland".

2.
Vet Res ; 49(1): 61, 2018 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-30005701

RESUMO

The mass vaccination of dogs is a proven tool for rabies prevention. Besides parenteral delivery of inactivated vaccines, over the past several decades, several self-replicating biologics, including modified-live, attenuated and recombinant viruses, have been evaluated for the oral vaccination of dogs against rabies. Vaccines are included within an attractive bait for oral consumption by free-ranging dogs. Due to the high affinity between dogs and humans, such biologics intended for oral vaccination of dogs (OVD) need to be efficacious as well as safe. Baits should be preferentially attractive to dogs and not to non-target species. Although many different types have been evaluated successfully, no universal bait has been identified to date. Moreover, high bait acceptance does not necessarily mean that vaccine efficacy and programmatic success is predictable. The use of OVD in the laboratory and field has demonstrated the safety and utility of this technology. Within a One Health context, OVD should be considered as part of a holistic plan for the global elimination of canine rabies.


Assuntos
Doenças do Cão/prevenção & controle , Vacina Antirrábica/administração & dosagem , Raiva/veterinária , Vacinação/veterinária , Administração Oral , Animais , Cães , Humanos , Raiva/prevenção & controle
3.
Vet Res ; 48(1): 57, 2017 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-28938920

RESUMO

RABORAL V-RG® is an oral rabies vaccine bait that contains an attenuated ("modified-live") recombinant vaccinia virus vector vaccine expressing the rabies virus glycoprotein gene (V-RG). Approximately 250 million doses have been distributed globally since 1987 without any reports of adverse reactions in wildlife or domestic animals since the first licensed recombinant oral rabies vaccine (ORV) was released into the environment to immunize wildlife populations against rabies. V-RG is genetically stable, is not detected in the oral cavity beyond 48 h after ingestion, is not shed by vaccinates into the environment, and has been tested for thermostability under a range of laboratory and field conditions. Safety of V-RG has been evaluated in over 50 vertebrate species, including non-human primates, with no adverse effects observed regardless of route or dose. Immunogenicity and efficacy have been demonstrated under laboratory and field conditions in multiple target species (including fox, raccoon, coyote, skunk, raccoon dog, and jackal). The liquid vaccine is packaged inside edible baits (i.e., RABORAL V-RG, the vaccine-bait product) which are distributed into wildlife habitats for consumption by target species. Field application of RABORAL V-RG has contributed to the elimination of wildlife rabies from three European countries (Belgium, France and Luxembourg) and of the dog/coyote rabies virus variant from the United States of America (USA). An oral rabies vaccination program in west-central Texas has essentially eliminated the gray fox rabies virus variant from Texas with the last case reported in a cow during 2009. A long-term ORV barrier program in the USA using RABORAL V-RG is preventing substantial geographic expansion of the raccoon rabies virus variant. RABORAL V-RG has also been used to control wildlife rabies in Israel for more than a decade. This paper: (1) reviews the development and historical use of RABORAL V-RG; (2) highlights wildlife rabies control programs using the vaccine in multiple species and countries; and (3) discusses current and future challenges faced by programs seeking to control or eliminate wildlife rabies.


Assuntos
Animais Selvagens/virologia , Vacina Antirrábica/uso terapêutico , Raiva/veterinária , Administração Oral , Animais , Raiva/prevenção & controle , Vacina Antirrábica/administração & dosagem , Vírus da Raiva/genética , Vacinas Sintéticas/uso terapêutico , Vaccinia virus/genética
4.
Vet Res ; 45: 77, 2014 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-25106552

RESUMO

The SAG2 vaccine (RABIGEN® SAG2) is a modified live attenuated rabies virus vaccine, selected from the SAD Bern strain in a two-step process of amino acid mutation using neutralizing monoclonal antibodies. The strain is genetically stable and does not spread in vivo or induce a persistent infection. Its absence of residual pathogenicity was extensively demonstrated in multiple target and non target species (such as wild carnivores and rodent species), including non-human primates. The efficacy of SAG2 baits was demonstrated according to the EU requirements for the red fox and raccoon dog. The use of safe and potent rabies vaccines such as SAG2 largely contributed to the elimination of rabies in Estonia, France, Italy and Switzerland. Importantly, these countries were declared free of rabies after few years of oral vaccination campaigns with SAG2 baits distributed with an appropriate strategy. The excellent tolerance of the SAG2 vaccine has been confirmed in the field since its first use in 1993. No safety issues have been reported, and in particular no vaccine-induced rabies cases were diagnosed, after the distribution of more than 20 million SAG2 baits in Europe.


Assuntos
Raposas , Vacina Antirrábica/administração & dosagem , Vírus da Raiva/fisiologia , Raiva/veterinária , Cães Guaxinins , Administração Oral , Animais , Erradicação de Doenças , Europa (Continente) , Raiva/prevenção & controle , Vacina Antirrábica/genética , Vacina Antirrábica/normas , Vacinação/veterinária , Vacinas Atenuadas/administração & dosagem , Vacinas Atenuadas/genética
5.
Neurotoxicology ; 82: 35-44, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33166614

RESUMO

Uranium exposure can lead to neurobehavioral alterations in particular of the monoaminergic system, even at non-cytotoxic concentrations. However, the mechanisms of uranium neurotoxicity after non-cytotoxic exposure are still poorly understood. In particular, imaging uranium in neurons at low intracellular concentration is still very challenging. We investigated uranium intracellular localization by means of synchrotron X-ray fluorescence imaging with high spatial resolution (< 300 nm) and high analytical sensitivity (< 1 µg.g-1 per 300 nm pixel). Neuron-like SH-SY5Y human cells differentiated into a dopaminergic phenotype were continuously exposed, for seven days, to a non-cytotoxic concentration (10 µM) of soluble natural uranyl. Cytoplasmic submicron uranium aggregates were observed accounting on average for 62 % of the intracellular uranium content. In some aggregates, uranium and iron were co-localized suggesting common metabolic pathways between uranium and iron storage. Uranium aggregates contained no calcium or phosphorous indicating that detoxification mechanisms in neuron-like cells are different from those described in bone or kidney cells. Uranium intracellular distribution was compared to fluorescently labeled organelles (lysosomes, early and late endosomes) and to fetuin-A, a high affinity uranium-binding protein. A strict correlation could not be evidenced between uranium and the labeled organelles, or with vesicles containing fetuin-A. Our results indicate a new mechanism of uranium cytoplasmic aggregation after non-cytotoxic uranyl exposure that could be involved in neuronal defense through uranium sequestration into less reactive species. The remaining soluble fraction of uranium would be responsible for protein binding and for the resulting neurotoxic effects.


Assuntos
Neurônios Dopaminérgicos/metabolismo , Urânio/metabolismo , Linhagem Celular , Neurônios Dopaminérgicos/química , Humanos , Compostos Organometálicos/metabolismo , Espectrometria por Raios X , Síncrotrons , Urânio/análise
6.
Environ Entomol ; 38(3): 514-23, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19508759

RESUMO

A 3-yr field survey was carried out in France, from 2002 to 2005, to study honey bee (Apis mellifera L.) colony health in relation to pesticide residues found in the colonies. This study was motivated by recent massive losses of honey bee colonies, and our objective was to examine the possible relationship between low levels of pesticide residues in apicultural matrices (honey, pollen collected by honey bees, beeswax) and colony health as measured by colony mortality and adult and brood population abundance. When all apicultural matrices were pooled together, the number of pesticide residue detected per sampling period (four sampling periods per year) and per apiary ranged from 0 to 9, with the most frequent being two (29.6%). No pesticide residues were detected during 12.7% of the sampling periods. Residues of imidacloprid and 6- chloronicotinic acid were the most frequently detected in pollen loads, honey, and honey bee matrices. Several pairs of active ingredients were present concurrently within honey bees and in pollen loads but not in beeswax and honey samples. No statistical relationship was found between colony mortality and pesticide residues. When pesticide residues from all matrices were pooled together, a mixed model analysis did not show a significant relationship between the presence of pesticide residues and the abundance of brood and adults, and no statistical relationship was found between colony mortality and pesticide residues. Thus, although certain pesticide residues were detected in apicultural matrices and occasionally with another pesticide residual, more work is needed to determine the role these residues play in affecting colony health.


Assuntos
Abelhas/efeitos dos fármacos , Inseticidas/efeitos adversos , Resíduos de Praguicidas/efeitos adversos , Criação de Animais Domésticos , Animais , França , Mel/análise , Inseticidas/análise , Resíduos de Praguicidas/análise , Ceras/análise
7.
PLoS Negl Trop Dis ; 13(12): e0007824, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31825968

RESUMO

BACKGROUND: Domestic carnivores can introduce rabies into disease-free countries or areas if they are incubating the disease and transported during the pre-symptomatic period. For pets moved into the European Union, the European Commission decided to establish a system of community approval of laboratories willing to carry out the rabies serological controls to guarantee an effective control system. As the specific institute to coordinate the approval of the laboratories, designated by the European Commission in 2000, our laboratory organizes annual proficiency tests (PT) for laboratories already agreed or willing to be agreed to perform rabies serological controls (by detecting rabies virus neutralizing antibodies only) in the frame of international trade. METHODOLOGY/PRINCIPAL FINDINGS: The assessment criteria of this PT rely on the analysis of the specificity and the intra-laboratory consistency. The approach used to evaluate the degree of laboratory consistency is based on the use of compiled data obtained from previous PT campaigns, and is measured by the quality of a regression model. By using historical data for calculating assigned values and associated standard deviations, instead of values obtained from only one campaign, they became robust without any additional statistical treatment. In the present paper, more than 800 historical values were compiled for each of the regression parameters. CONCLUSIONS/SIGNIFICANCE: Since the beginning of these PT schemes in 1999, the overall percentage of failing laboratories remained stable over the years (4.1%) while the number of participants increased to 79 in 2018. This highlighted the robustness and the consistency of the statistical analyses used to assess the laboratory's performance over the years. The improvements carried out and the consistency of our statistical analyses have resulted in the compliance of the rabies serology PT with the ISO/IEC 17043 and ISO 13528:2015 International Standards.


Assuntos
Anticorpos Antivirais/sangue , Doenças do Cão/diagnóstico , Ensaio de Proficiência Laboratorial , Vírus da Raiva/imunologia , Raiva/veterinária , Testes Sorológicos/métodos , Animais , Cães , União Europeia , Testes de Neutralização/métodos , Raiva/diagnóstico
8.
Endocrinology ; 149(12): 6289-99, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18687784

RESUMO

Despite medical advice, 20-30% of female smokers continue to smoke during pregnancy. Epidemiological studies have associated maternal smoking with increased risk of obesity and type-2 diabetes in the offspring. In the present study, we investigated the impact of prenatal nicotine exposure (3 mg/kg in Sprague Dawley rats via osmotic Alzet minipumps) on the early endocrine pancreas and adipose tissue development in rat pups before weaning. Body weight, fat deposition, food intake and food efficiency, cold tolerance, spontaneous physical activity, glucose utilization, and insulin sensitivity were also examined at adulthood. Prenatal nicotine exposure led to a decrease in endocrine pancreatic islet size and number at 7 d of life (postnatal d 7), which corroborates with a decrease in gene expression of specific transcription factors such as pancreatic and duodenal homeobox 1, Pax-6, Nkx6.1, and of hormones such as insulin and glucagon. The prenatal nicotine exposure also led to an increase in epididymal white adipose tissue weight at weaning (postnatal d 21), and marked hypertrophy of adipocytes, with increased gene expression of proadipogenic transcription factors such as CAAT-enhancer-binding protein-alpha, peroxisome proliferator activated receptor-gamma, and sterol regulatory element binding protein-1C. These early tissue alterations led to significant metabolic consequences, as shown by increased body weight and fat deposition, increased food efficiency on high-fat diet, cold intolerance, reduced physical activity, and glucose intolerance combined with insulin resistance observed at adulthood. These results prove a direct association between fetal nicotine exposure and offspring metabolic syndrome with early signs of dysregulations of adipose tissue and pancreatic development.


Assuntos
Peso Corporal/efeitos dos fármacos , Glucose/metabolismo , Ilhotas Pancreáticas/efeitos dos fármacos , Nicotina/toxicidade , Efeitos Tardios da Exposição Pré-Natal/metabolismo , Adipogenia/efeitos dos fármacos , Tecido Adiposo/efeitos dos fármacos , Tecido Adiposo/crescimento & desenvolvimento , Tecido Adiposo/metabolismo , Animais , Calorimetria , Metabolismo dos Carboidratos/efeitos dos fármacos , Ingestão de Alimentos/efeitos dos fármacos , Feminino , Estimulantes Ganglionares/administração & dosagem , Estimulantes Ganglionares/toxicidade , Teste de Tolerância a Glucose , Resistência à Insulina , Ilhotas Pancreáticas/crescimento & desenvolvimento , Masculino , Nicotina/administração & dosagem , Gravidez , Efeitos Tardios da Exposição Pré-Natal/induzido quimicamente , Efeitos Tardios da Exposição Pré-Natal/fisiopatologia , Ratos , Ratos Sprague-Dawley
9.
Vet Microbiol ; 124(3-4): 286-97, 2007 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-17532581

RESUMO

Performances of an ELISA, an immunofluorescence assay (IFA) and a complement fixation test (CFT) were assessed for detecting antibodies against Coxiella burnetii after Q fever abortions in naturally infected goats. The goal of the study was to provide information useful for veterinary serodiagnosis in regard to categories of goats either experiencing Q fever abortion or not, blood sampling times and recommended cut-offs. The study was conducted on eight goat herds with evidence of C. burnetii abortions. In each herd, at least 5 goats that had aborted and 10 goats prior to parturition or at term were monitored 15, 30 and 60 days (D15, D30, D60) after the onset of Q fever abortion. The overall CFT results distribution did not differ between the two groups of goats and showed poor agreement with the ELISA results. In contrast, the ELISA and IFA results revealed comparable significant differences, but overall the ELISA test was slightly more sensitive than the IFA test. Seroprevalence, according to ELISA and IFA respectively, was higher in the aborting (88% and 82%) than in the non-aborting group (60% and 50%). High levels of serum antibodies were detected in goats post-abortion with an average of 114 %OD using ELISA and a log10(titer) of 2.4 using IFA. Strongly positive ELISA (%OD>80) and positive IFA results (log10(titers)>1.9) were significantly associated with abortion. Sampling on D15 gave the best association with ORs of 10 for ELISA and 6 for IFA. The practical interest of these results is discussed.


Assuntos
Anticorpos Antibacterianos/sangue , Coxiella burnetii/imunologia , Doenças das Cabras/diagnóstico , Febre Q/veterinária , Aborto Animal/diagnóstico , Aborto Animal/microbiologia , Animais , Antígenos de Bactérias/imunologia , Testes de Fixação de Complemento/métodos , Testes de Fixação de Complemento/normas , Testes de Fixação de Complemento/veterinária , Coxiella burnetii/isolamento & purificação , Diagnóstico Diferencial , Ensaio de Imunoadsorção Enzimática/métodos , Ensaio de Imunoadsorção Enzimática/normas , Ensaio de Imunoadsorção Enzimática/veterinária , Feminino , Técnica Indireta de Fluorescência para Anticorpo/métodos , Técnica Indireta de Fluorescência para Anticorpo/normas , Técnica Indireta de Fluorescência para Anticorpo/veterinária , Doenças das Cabras/epidemiologia , Cabras , Gravidez , Febre Q/diagnóstico , Febre Q/epidemiologia , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Estudos Soroepidemiológicos
10.
J Econ Entomol ; 99(2): 253-62, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16686121

RESUMO

In 2002, a field survey was initiated on French apiaries to monitor weakness of honey bee, Apis mellifera L., colonies. Apiaries were evenly distributed in five sites located on continental France. Five colonies were randomly selected in each apiary, leading to a total of 125 studied honey bee colonies. For 3 yr (starting in autumn 2002), colonies were visited four times per year: after winter, before summer, during summer, and before winter. Pollen loads from traps were collected at each visit. Multiresidue analyses were performed in pollen to search residues of 36 different molecules. Specific analyses were conducted to search fipronil and metabolites and also imidacloprid and metabolites. Residues of 19 searched compounds were found in samples. Contamination by pesticides ranged from 50 to 0%. Coumaphos and tau-fluvalinate residues were the most concentrated of all residues (mean concentrations were 925.0 and 487.2 microg/kg, respectively). Fipronil and metabolite contents were superior to the limit of detection in 16 samples. Residues of fipronil were found in 10 samples. Nine samples contained the sulfone compound, and three samples contained the desulfinyl compound. Residues of imidacloprid and 6-chloronicotinic acid were found in 69% of samples. Imidacloprid contents were quantified in 11 samples with values ranging from 1.1 to 5.7 microg/kg. 6-Chloronicotinic acid content was superior to the limit of quantification in 28 samples with values ranging from 0.6 to 9.3 microg/kg. Statistical tests showed no difference between places of sampling with the exception of fipronil. Possible origins of these contaminations, concentration and toxicity of pesticides, and the possible consequences for bees are discussed.


Assuntos
Abelhas/fisiologia , Resíduos de Praguicidas/análise , Pólen/química , Animais , Abelhas/efeitos dos fármacos , França , Inseticidas/análise , Inseticidas/toxicidade , Dose Letal Mediana , Resíduos de Praguicidas/toxicidade
11.
Diabetes ; 51(5): 1461-9, 2002 May.
Artigo em Inglês | MEDLINE | ID: mdl-11978643

RESUMO

Acute suppression of dipeptidyl peptidase IV (DPP-IV) activity improves glucose tolerance in the Zucker fatty rat, a rodent model of impaired glucose tolerance, through stabilization of glucagon-like peptide (GLP)-1. This study describes the effects of a new and potent DPP-IV inhibitor, FE 999011, which is able to suppress plasma DPP-IV activity for 12 h after a single oral administration. In the Zucker fatty rat, FE 999011 dose-dependently attenuated glucose excursion during an oral glucose tolerance test and increased GLP-1 (7-36) release in response to intraduodenal glucose. Chronic treatment with FE 999011 (10 mg/kg, twice a day for 7 days) improved glucose tolerance, as suggested by a decrease in the insulin-to-glucose ratio. In the Zucker diabetic fatty (ZDF) rat, a rodent model of type 2 diabetes, chronic treatment with FE 999011 (10 mg/kg per os, once or twice a day) postponed the development of diabetes, with the twice-a-day treatment delaying the onset of hyperglycemia by 21 days. In addition, treatment with FE 999011 stabilized food and water intake to prediabetic levels and reduced hypertriglyceridemia while preventing the rise in circulating free fatty acids. At the end of treatment, basal plasma GLP-1 levels were increased, and pancreatic gene expression for GLP-1 receptor was significantly upregulated. This study demonstrates that DPP-IV inhibitors such as FE 999011 could be of clinical value to delay the progression from impaired glucose tolerance to type 2 diabetes.


Assuntos
Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus/tratamento farmacológico , Dipeptidil Peptidase 4/sangue , Nitrilas/farmacologia , Obesidade , Inibidores de Proteases/farmacologia , Pirrolidinas/farmacologia , Animais , Glicemia , Diabetes Mellitus/sangue , Diabetes Mellitus/enzimologia , Diabetes Mellitus Tipo 2/sangue , Ingestão de Líquidos/efeitos dos fármacos , Ingestão de Alimentos/efeitos dos fármacos , Ácidos Graxos não Esterificados/sangue , Expressão Gênica/fisiologia , Glucagon/sangue , Peptídeo 1 Semelhante ao Glucagon , Receptor do Peptídeo Semelhante ao Glucagon 1 , Teste de Tolerância a Glucose , Humanos , Insulina/sangue , Masculino , Nitrilas/química , Pâncreas/fisiologia , Fragmentos de Peptídeos/sangue , Inibidores de Proteases/química , Precursores de Proteínas/sangue , Pirrolidinas/química , Ratos , Ratos Zucker , Receptores de Glucagon/genética , Triglicerídeos/sangue , Aumento de Peso/efeitos dos fármacos
12.
Pest Manag Sci ; 61(2): 111-25, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15619715

RESUMO

Two groups of eight honey bee colonies were fed with two different concentrations of imidacloprid in saccharose syrup during summer (each colony was given 1 litre of saccharose syrup containing 0.5 microg litre(-1) or 5 microg litre(-1) of imidacloprid on 13 occasions). Their development and survival were followed in parallel with control hives (unfed or fed with saccharose syrup) until the end of the following winter. The parameters followed were: adult bee activity (number of bee entering the hive and pollen carrying activity), adult bee population level, capped brood area, frequency of parasitic and other diseases, mortality, number of frames with brood after wintering and a global score of colonies after wintering. The only parameters linked to feeding with imidacloprid-supplemented saccharose syrup when compared with feeding with non-supplemented syrup were: a statistically non-significant higher activity index of adult bees, a significantly higher frequency of pollen carrying during the feeding period and a larger number of capped brood cells. When imidacloprid was no longer applied, activity and pollen carrying were re-established at a similar level for all groups. Repeated feeding with syrup supplemented with imidacloprid did not provoke any immediate or any delayed mortality before, during or following the next winter, whereas such severe effects are described by several French bee keepers as a consequence of imidacloprid use for seed dressing in neighbouring cultures. In any case, during the whole study, mortality was very low in all groups, with no difference between imidacloprid-fed and control colonies. Further research should now address several hypotheses: the troubles described by bee keepers have causes other than imidacloprid; if such troubles are really due to this insecticide, they may only be observed either when bees consume contaminated pollen, when no other sources of food are available, in the presence of synergic factors (that still need to be identified), with some particular races of bees or when colonies are not strong and healthy.


Assuntos
Abelhas/efeitos dos fármacos , Imidazóis/toxicidade , Inseticidas/toxicidade , Animais , Abelhas/fisiologia , Relação Dose-Resposta a Droga , Mel , Neonicotinoides , Nitrocompostos , Reprodução/efeitos dos fármacos , Estações do Ano , Sacarose
13.
Endocrinology ; 145(1): 304-10, 2004 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-14525913

RESUMO

Neuropeptide Y (NPY) is a powerful orexigenic neurotransmitter. The NPY Y1 and Y5 receptors have been implicated in mediating the appetite-stimulating activity of NPY. To further investigate the importance of these two receptors in NPY-induced hyperphagia after chronic central administration, we used mice lacking either Npy1r or Npy5r expression. NPY infusion into the lateral ventricle of wild-type mice stimulated food intake and induced obesity over a 7-d period. Fat pad weight as well as plasma insulin, leptin, and corticosterone levels were strongly increased in NPY-treated mice. In addition, NPY infusion resulted in a significant decrease in hypothalamic NPY and proopiomelanocortin expression. Interestingly, the lack of either Npy1r or Npy5r expression in knockout mice did not affect such feeding response to chronic NPY infusion. Moreover, the obesity syndrome that developed in these animals was similar to that in wild-type animals. Taken together, these data strongly suggest biological redundancies between Y1 and Y5 receptor signaling in the NPY-mediated control of food intake.


Assuntos
Comportamento Alimentar/efeitos dos fármacos , Neuropeptídeo Y/farmacologia , Obesidade/fisiopatologia , Receptores de Neuropeptídeo Y/genética , Tecido Adiposo/anatomia & histologia , Animais , Peso Corporal/efeitos dos fármacos , Corticosterona/sangue , Ingestão de Líquidos/efeitos dos fármacos , Ingestão de Alimentos/efeitos dos fármacos , Hiperfagia/induzido quimicamente , Injeções Intraventriculares , Insulina/sangue , Ventrículos Laterais , Leptina/sangue , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Neuropeptídeo Y/genética , Pró-Opiomelanocortina/genética , RNA Mensageiro/análise
14.
Brain Res ; 976(2): 159-70, 2003 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-12763250

RESUMO

Corticotropin-releasing hormone (CRH) and vasopressin (AVP) participate in the endocrine, autonomic, immunological and behavioral response to stress. CRH and AVP receptors are found in hippocampus and anterior pituitary, where mineralocorticoid (MR) and glucocorticoid (GR) receptors are abundant. We investigated the possible influence of CRH and AVP on the regulation of MR and GR in both tissues. CRH, AVP, or their antagonists were administered to adrenalectomized rats substituted with corticosterone, to avoid interference with adrenal secretion. Repeated i.c.v. oCRH injections (10 microgram) for 5 days significantly decreased MR and GR mRNA in hippocampus and MR mRNA in anterior pituitary. AVP significantly increased both corticosteroid receptor mRNAs, as repeated i.c.v. injections (5 microgram) for 5 days in hippocampus, and as continuous i.c.v. infusion (10 ng/h/5 days) in anterior pituitary. The i.c.v. infusion of 5 or 10 microgram/day of the alpha-helical CRH antagonist during intermittent restraint stress (5 days), induced a significant decrease in hippocampal MR binding. In anterior pituitary, 5 microgram/day significantly decreased MR binding, while 10 microgram/day significantly increased GR binding. Under the same conditions of stress, the infusion of 15 microgram/day of the vasopressin V1a/1b receptor antagonist [dP Tyr (Me)(2)AVP] significantly increased MR and GR binding in hippocampus and anterior pituitary; 5 microgram/day significantly decreased pituitary MR binding. Our results show that CRH and AVP regulate MR and GR in hippocampus and anterior pituitary. This reveals another important function of CRH and AVP, which could be relevant to understand stress adaptation and the pathophysiology of stress-related disorders like major depression.


Assuntos
Arginina Vasopressina/análogos & derivados , Arginina Vasopressina/farmacologia , Hormônio Liberador da Corticotropina/farmacologia , Hipocampo/efeitos dos fármacos , Adeno-Hipófise/efeitos dos fármacos , Receptores de Glucocorticoides/genética , Receptores de Mineralocorticoides/genética , Vasoconstritores/farmacologia , Animais , Doença Crônica , Expressão Gênica/efeitos dos fármacos , Hipocampo/fisiologia , Antagonistas de Hormônios/farmacologia , Injeções Intraventriculares , Masculino , Fragmentos de Peptídeos/farmacologia , Adeno-Hipófise/fisiologia , Ratos , Ratos Sprague-Dawley , Receptores de Glucocorticoides/metabolismo , Receptores de Mineralocorticoides/metabolismo , Estresse Fisiológico/fisiopatologia
15.
J Vet Diagn Invest ; 15(3): 281-5, 2003 May.
Artigo em Inglês | MEDLINE | ID: mdl-12735352

RESUMO

Serologic diagnosis of ovine contagious agalactia (Mycoplasma agalactiae) with the enzyme-linked immunosorbent assay (ELISA) developed by Agence Française de Sécurité Sanitaire des Aliments (AFSSA) may produce a few false-positive (FP) and false-negative (FN) results. When the prevalence of disease is low, these erroneous results may generate problems for eradication schemes. To prevent this, 2 commercial ELISAs were compared with the AFSSA ELISA. Flocks of known status were selected and classified into 4 categories: true positive (TP), FP, true negative (TN), and FN; 20 sheep per flock were submitted for blood sampling. A flock was considered positive when at least 1 out of 20 sera was positive or 2 sera were doubtful. In the flock, the diagnostic sensitivity of the 3 kits was very good (100%), and the diagnostic specificity showed an improvement from 46% (AFSSA test) to 88% and 92% (commercial tests). Considering individual animals, very few positive ewes were detected within TN or FP flocks; the proportion of positive ewes varied greatly from one kit to another (48% to 82%) within TP flocks. The kinetics of antibody response in sheep experimentally infected with various field strains of M. agalactiae were quite similar with all 3 ELISAs. The agreement between the 3 tests, assessed using the kappa value, varied from moderate to good (respective values of 0.56, 0.61, and 0.86). The 2 commercial ELISAs showed better performances, probably because of a superior analytical sensitivity, and are a good alternative for the serodiagnosis of contagious agalactia in sheep.


Assuntos
Ensaio de Imunoadsorção Enzimática/métodos , Infecções por Mycoplasma/diagnóstico , Infecções por Mycoplasma/veterinária , Mycoplasma/isolamento & purificação , Doenças dos Ovinos/diagnóstico , Animais , Feminino , Mycoplasma/imunologia , Infecções por Mycoplasma/imunologia , Kit de Reagentes para Diagnóstico/veterinária , Sensibilidade e Especificidade , Doenças dos Ovinos/imunologia , Doenças dos Ovinos/microbiologia , Carneiro Doméstico , Fatores de Tempo
16.
Endocrinology ; 154(11): 4237-48, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24029240

RESUMO

Abnormally high GH/IGF-I levels, most often caused by adenomas arising from pituitary somatotrophs, generate deleterious effects. We recently described a targeted secretion inhibitor (SXN101742) comprising a GHRH domain and the endopeptidase domain of botulinum toxin serotype D (GHRH-light chain endopeptidase type D domain [LC/D] associated to a heavy chain translocation domain [HN]) able to down-regulate the GH/IGF-I axis. In the present study, we compared the effect of a single iv bolus of a related molecule developed for clinical studies (SXN101959, 1 mg/kg) with a sc infusion of the somatostatin analog octreotide (SMS201-995, 10 µg/kg · h) to lower GH/IGF-I activity in growing male rats. Ten days after administration of SXN101959 or initiation of the octreotide infusion, body and pituitary weights, body length, GH peaks, and IGF-I production were reduced by both treatments but to a greater extent with SXN101959. In contrast to unaltered GH gene expression and increased GH storage in pituitaries from octreotide-treated rats, the inhibition of GH secretion was associated with a collapse of both GH mRNA and protein level in pituitaries from SXN101959-treated rats, in line with a specific decrease in hypothalamic GHRH production, not observed with octreotide. SXN101959 did not induce major apoptotic events in anterior pituitary and exhibited a reversible mode of action with full recovery of somatotroph cell functionality 30 days after treatment. Octreotide infusion permanently decreased ghrelin levels, whereas SXN101959 only transiently attenuated ghrelinemia. Both treatments limited bone mass acquisition and altered specifically tissues development. In conclusion, SXN101959 exerts a powerful and reversible inhibitory action on the somatotropic axis. Specific features of SXN101959, including long duration of action coupled to a strong inhibition of pituitary GH synthesis, represent advantages when treating overproduction of GH.


Assuntos
Toxinas Botulínicas/farmacologia , Hormônio do Crescimento/antagonistas & inibidores , Fator de Crescimento Insulin-Like I/metabolismo , Octreotida/farmacologia , Proteínas Recombinantes de Fusão/farmacologia , Animais , Desenvolvimento Ósseo/efeitos dos fármacos , Hormônio do Crescimento/metabolismo , Fator de Crescimento Insulin-Like I/genética , Masculino , Ratos
17.
PLoS One ; 7(11): e50131, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23166830

RESUMO

Poor fetal growth, also known as intrauterine growth restriction (IUGR), is a worldwide health concern. IUGR is commonly associated with both an increased risk in perinatal mortality and a higher prevalence of developing chronic metabolic diseases later in life. Obesity, type 2 diabetes or metabolic syndrome could result from noxious "metabolic programming." In order to better understand early alterations involved in metabolic programming, we modeled IUGR rat pups through either prenatal exposure to synthetic glucocorticoid (dams infused with dexamethasone 100 µg/kg/day, DEX) or prenatal undernutrition (dams feeding restricted to 30% of ad libitum intake, UN). Physiological (glucose and insulin tolerance), morphometric (automated tissue image analysis) and transcriptomic (quantitative PCR) approaches were combined during early life of these IUGR pups with a special focus on their endocrine pancreas and adipose tissue development. In the absence of catch-up growth before weaning, DEX and UN IUGR pups both presented basal hyperglycaemia, decreased glucose tolerance, and pancreatic islet atrophy. Other early metabolic defects were model-specific: DEX pups presented decreased insulin sensitivity whereas UN pups exhibited lowered glucose-induced insulin secretion and more marked alterations in gene expression of pancreatic islet and adipose tissue development regulators. In conclusion, these results show that before any catch-up growth, IUGR rats present early physiologic, morphologic and transcriptomic defects, which can be considered as initial mechanistic basis of metabolic programming.


Assuntos
Dexametasona/efeitos adversos , Retardo do Crescimento Fetal/metabolismo , Desnutrição/metabolismo , Efeitos Tardios da Exposição Pré-Natal/metabolismo , Tecido Adiposo/crescimento & desenvolvimento , Tecido Adiposo/metabolismo , Análise de Variância , Animais , Glicemia/metabolismo , Western Blotting , Pesos e Medidas Corporais , Peptídeo C/sangue , Corticosterona/sangue , Primers do DNA/genética , Feminino , Perfilação da Expressão Gênica , Insulina/sangue , Resistência à Insulina/fisiologia , Ilhotas Pancreáticas/crescimento & desenvolvimento , Ilhotas Pancreáticas/metabolismo , Ilhotas Pancreáticas/patologia , Leptina/sangue , Gravidez , Radioimunoensaio , Ratos , Ratos Sprague-Dawley , Reação em Cadeia da Polimerase em Tempo Real
18.
J Clin Invest ; 122(9): 3295-306, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22850878

RESUMO

Botulinum neurotoxins (BoNTs) are zinc endopeptidases that block release of the neurotransmitter acetylcholine in neuromuscular synapses through cleavage of soluble N-ethylmaleimide-sensitive fusion (NSF) attachment protein receptor (SNARE) proteins, which promote fusion of synaptic vesicles to the plasma membrane. We designed and tested a BoNT-derived targeted secretion inhibitor (TSI) targeting pituitary somatotroph cells to suppress growth hormone (GH) secretion and treat acromegaly. This recombinant protein, called SXN101742, contains a modified GH-releasing hormone (GHRH) domain and the endopeptidase domain of botulinum toxin serotype D (GHRH-LHN/D, where HN/D indicates endopeptidase and translocation domain type D). In vitro, SXN101742 targeted the GHRH receptor and depleted a SNARE protein involved in GH exocytosis, vesicle-associated membrane protein 2 (VAMP2). In vivo, administering SXN101742 to growing rats produced a dose-dependent inhibition of GH synthesis, storage, and secretion. Consequently, hepatic IGF1 production and resultant circulating IGF1 levels were reduced. Accordingly, body weight, body length, organ weight, and bone mass acquisition were all decreased, reflecting the biological impact of SXN101742 on the GH/IGF1 axis. An inactivating 2-amino acid substitution within the zinc coordination site of the endopeptidase domain completely abolished SXN101742 inhibitory actions on GH and IGF1. Thus, genetically reengineered BoNTs can be targeted to nonneural cells to selectively inhibit hormone secretion, representing a new approach to treating hormonal excess.


Assuntos
Regulação para Baixo/efeitos dos fármacos , Hormônio do Crescimento/metabolismo , Inibidores do Crescimento/farmacologia , Fator de Crescimento Insulin-Like I/metabolismo , Proteínas Recombinantes de Fusão/farmacologia , Acromegalia/tratamento farmacológico , Animais , Área Sob a Curva , Peso Corporal/efeitos dos fármacos , Toxinas Botulínicas/química , Toxinas Botulínicas/genética , Linhagem Celular , AMP Cíclico/metabolismo , Relação Dose-Resposta a Droga , Hormônio do Crescimento/sangue , Hormônio Liberador de Hormônio do Crescimento/química , Hormônio Liberador de Hormônio do Crescimento/genética , Inibidores do Crescimento/química , Lâmina de Crescimento/efeitos dos fármacos , Lâmina de Crescimento/crescimento & desenvolvimento , Lâmina de Crescimento/patologia , Fator de Crescimento Insulin-Like I/genética , Fígado/metabolismo , Masculino , Tamanho do Órgão/efeitos dos fármacos , Hipófise/efeitos dos fármacos , Hipófise/metabolismo , Hipófise/patologia , Prolactina/metabolismo , Estrutura Terciária de Proteína , Proteólise , Ratos , Ratos Sprague-Dawley , Proteínas Recombinantes de Fusão/química , Proteína 2 Associada à Membrana da Vesícula/química
19.
Environ Toxicol Chem ; 30(1): 103-11, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20853451

RESUMO

The frequency of occurrence and relative concentration of 44 pesticides in apicultural (Apis mellifera) matrices collected from five French locations (24 apiaries) were assessed from 2002 to 2005. The number and nature of the pesticides investigated varied with the matrices examined-living honeybees, pollen loads, honey, and beeswax. Pollen loads and beeswax had the highest frequency of pesticide occurrence among the apiary matrices examined in the present study, whereas honey samples had the lowest. The imidacloprid group and the fipronil group were detected in sufficient amounts in all matrices to allow statistical comparisons. Some seasonal variation was shown when residues were identified in pollen loads. Given the results (highest frequency of presence) and practical aspects (easy to collect; matrix with no turnover, unlike with bees that are naturally renewed), pollen loads were the best matrix for assessing the presence of pesticide residues in the environment in our given conditions.


Assuntos
Abelhas/metabolismo , Monitoramento Ambiental/métodos , Poluentes Ambientais/metabolismo , Praguicidas/metabolismo , Animais , Poluentes Ambientais/análise , Poluição Ambiental/estatística & dados numéricos , França , Mel/análise , Modelos Biológicos , Praguicidas/análise , Pólen/química , Ceras/química
20.
Int J Dev Neurosci ; 29(1): 37-43, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20955774

RESUMO

In recent years, considerable research has focused on the biological effect of endocrine-disrupting chemicals. Bisphenol A (BPA) has been implicated as an endocrine-disrupting chemical (EDC) due to its ability to mimic the action of endogenous estrogenic hormones. The aim of this study was to assess the effect of perinatal exposure to BPA on cerebral structural development and metabolism after birth. BPA (1mg/l) was administered in the drinking water of pregnant dams from day 6 of gestation until pup weaning. At postnatal day 20, in vivo metabolite concentrations in the rat pup hippocampus were measured using high field proton magnetic resonance spectroscopy. Further, brain was assessed histologically for growth, gross morphology, glial and neuronal development and extent of myelination. Localized proton magnetic resonance spectroscopy ((1)H MRS) showed in the BPA-exposed rat a significant increase in glutamate concentration in the hippocampus as well as in the Glu/Asp ratio. Interestingly these two metabolites are metabolically linked together in the malate-aspartate metabolic shuttle. Quantitative histological analysis revealed that the density of NeuN-positive neurons in the hippocampus was decreased in the BPA-treated offspring when compared to controls. Conversely, the density of GFAP-positive astrocytes in the cingulum was increased in BPA-treated offspring. In conclusion, exposure to low-dose BPA during gestation and lactation leads to significant changes in the Glu/Asp ratio in the hippocampus, which may reflect impaired mitochondrial function and also result in neuronal and glial developmental alterations.


Assuntos
Encéfalo , Disruptores Endócrinos/farmacologia , Estrogênios não Esteroides/farmacologia , Lactação/efeitos dos fármacos , Fenóis/farmacologia , Efeitos Tardios da Exposição Pré-Natal , Animais , Ácido Aspártico/metabolismo , Compostos Benzidrílicos , Encéfalo/efeitos dos fármacos , Encéfalo/embriologia , Encéfalo/crescimento & desenvolvimento , Metabolismo Energético/efeitos dos fármacos , Feminino , Ácido Glutâmico/metabolismo , Humanos , Espectroscopia de Ressonância Magnética/métodos , Masculino , Neuroglia/efeitos dos fármacos , Neuroglia/metabolismo , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Gravidez , Ratos , Ratos Sprague-Dawley
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