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1.
Eur J Pediatr ; 178(10): 1545-1558, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31463766

RESUMO

We sought to establish guidelines for hygiene care in newborns based on a systematic review of the literature and grading of evidence using the Groupe de Réflexion et d'Evaluation de l'Environement des Nouveau-nés (GREEN) methodology. We examined 45 articles and 4 reports from safety agencies. These studies recommend a tub bath (rather than a sponge bath) for full-term infants and a swaddle bath for preterm newborns. They also recommend against daily cleansing of preterm infants. The literature emphasized that hygiene care must consider the clinical state of the newborn, including the level of awareness and behavioral responses. Hospitalized newborns treated with topical agents may also experience high exposure to potentially harmful excipients of interest. Caregivers should therefore be aware of the excipients present in the different products they use. In high-resource countries, the available data do not support the use of protective topical agents for preterm infants.Conclusions: We recommend individualization of hygiene care for newborns. There is increasing concern regarding the safety of excipients in topical agents that are used in neonatology. A multidisciplinary approach should be used to identify an approach that requires lower levels of excipients and alternative excipients. What is known: • Hygiene care is one of the most basic and widespread types of care received by healthy and sick newborns worldwide. • There is no current guideline on hygiene for preterm or hospitalized term newborn. What is new: • The French Group of Reflection and Evaluation of the environment of Newborns (GREEN) provided here guidelines based on the current body of evidence. • Caregivers should be aware of the many issues related to hygiene care of newborns including newborns' behavioral responses to hygiene care, exposition to excipients of interest, and the potential risk of protective topical agents in a preterm infant. provided here guidelines based on the current body of evidence. • Caregivers should be aware of the many issues related to hygiene care of newborns including newborns' possible behavioral responses to hygiene care, exposition to excipients of interest and the potential risk of protective topical agents in a preterm infant.


Assuntos
Higiene/normas , Cuidado do Lactente/normas , Guias de Prática Clínica como Assunto , Administração Tópica , França , Humanos , Recém-Nascido , Recém-Nascido Prematuro , Neonatologia/métodos , Fenômenos Fisiológicos da Pele
2.
Neuroimage ; 167: 23-30, 2018 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-29122719

RESUMO

Interocular interaction in the visual system occurs under dichoptic conditions when contrast and luminance are imbalanced between the eyes. Human psychophysical investigations suggest that interocular interaction can be explained by a contrast normalization model. However, the neural processes that underlie such interactions are still unresolved. We set out to assess, for the first time, the proposed normalization model of interocular contrast interactions using magnetoencephalography (MEG) and to extend this model to incorporate interactions based on interocular luminance differences. We used MEG to record steady-state visual evoked responses (SSVER), and functional magnetic resonance imaging (fMRI) to obtain individual retinotopic maps that we used in combination with MEG source imaging in healthy participants. Binary noise stimuli were presented in monocular or dichoptic viewing and were frequency-tagged at 4 and 6 Hz. The contrast of the stimuli was modulated in a range between 0 and 32%. Monocularly, we reduced the luminance by placing a 1.5 ND filter over one eye in the maximal contrast condition. This ND filter reduces the mean light level by a factor of 30 without any alteration to the physical contrast. We observed in visual area V1 a monotonic increase in the magnitude of SSVERs with changes in contrast from 0 to 32%. For both eyes, dichoptic masking induced a decrease in SSVER signal power. This power decrease was well explained by the normalization model. Reducing mean luminance delayed monocular processing by approximately 38 ms in V1. The reduced luminance also decreased the masking ability of the eye under the filter. Predictions based on a temporal filtering model for the interocular luminance difference prior to the model's binocular combination stage were incorporated to update the normalization model. Our results demonstrate that the signals resulting from different contrast or luminance stimulation of the two eyes are combined in a way that can be explained by an interocular normalization model.


Assuntos
Sensibilidades de Contraste/fisiologia , Potenciais Evocados Visuais/fisiologia , Magnetoencefalografia/métodos , Visão Binocular/fisiologia , Visão Monocular/fisiologia , Córtex Visual/fisiologia , Adulto , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Modelos Teóricos , Adulto Jovem
3.
Glob Environ Change ; 52: 286-313, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30679888

RESUMO

Competition over limited water resources is one of the main concerns for the coming decades. Although water issues alone have not been the sole trigger for warfare in the past, tensions over freshwater management and use represent one of the main concerns in political relations between riparian states and may exacerbate existing tensions, increase regional instability and social unrest. Previous studies made great efforts to understand how international water management problems were addressed by actors in a more cooperative or confrontational way. In this study, we analyze what are the pre-conditions favoring the insurgence of water management issues in shared water bodies, rather than focusing on the way water issues are then managed among actors. We do so by proposing an innovative analysis of past episodes of conflict and cooperation over transboundary water resources (jointly defined as "hydro-political interactions"). On the one hand, we aim at highlighting the factors that are more relevant in determining water interactions across political boundaries. On the other hand, our objective is to map and monitor the evolution of the likelihood of experiencing hydro-political interactions over space and time, under changing socioeconomic and biophysical scenarios, through a spatially explicit data driven index. Historical cross-border water interactions were used as indicators of the magnitude of corresponding water joint-management issues. These were correlated with information about river basin freshwater availability, climate stress, human pressure on water resources, socioeconomic conditions (including institutional development and power imbalances), and topographic characteristics. This analysis allows for identification of the main factors that determine water interactions, such as water availability, population density, power imbalances, and climatic stressors. The proposed model was used to map at high spatial resolution the probability of experiencing hydro-political interactions worldwide. This baseline outline is then compared to four distinct climate and population density projections aimed to estimate trends for hydro-political interactions under future conditions (2050 and 2100), while considering two greenhouse gases emission scenarios (moderate and extreme climate change). The combination of climate and population growth dynamics is expected to impact negatively on the overall hydro-political risk by increasing the likelihood of water interactions in the transboundary river basins, with an average increase ranging between 74.9% (2050 - population and moderate climate change) to 95% (2100 - population and extreme climate change). Future demographic and climatic conditions are expected to exert particular pressure on already water stressed basins such as the Nile, the Ganges/Brahmaputra, the Indus, the Tigris/Euphrates, and the Colorado. The results of this work allow us to identify current and future areas where water issues are more likely to arise, and where cooperation over water should be actively pursued to avoid possible tensions especially under changing environmental conditions. From a policy perspective, the index presented in this study can be used to provide a sound quantitative basis to the assessment of the Sustainable Development Goal 6, Target 6.5 "Water resources management", and in particular to indicator 6.5.2 "Transboundary cooperation".

4.
Arch Pediatr ; 23(9): 974-82, 2016 Sep.
Artigo em Francês | MEDLINE | ID: mdl-27496640

RESUMO

BACKGROUND: The experience of becoming the parent of a sick or premature newborn can be particularly distressing for parents. They often encounter challenges to the development of their parenting roles. Perception of the hospital stay has never been analyzed on a large scale. OBJECTIVE: To analyze parents' perception of their involvement in the care of their newborn. METHODS: An internet-based survey started in France in February 2014 on the basis of a validated questionnaire composed of 222 neonatal care-related items. A quantitative and qualitative analysis was performed on the items dealing with parents' involvement until August 2014. RESULTS: The survey was completed by 1500 parents, 98 % of whom were mothers. The infants had a mean GA of 32 weeks and a mean birth weight of 1600g. Parents rated their first care of their infant with mixed emotions (joy, stress, etc.). Parents were willing to practice new skills through guided participation, even for more complex care. Skin-to-skin care was only proposed after 7 days for 20 % of the parents; 10 % of the parents did not feel secure during this practice. The need for privacy and professional guidance was essential for meaningful skin-to-skin contact. DISCUSSION: Parents' perception of participating actively in their infant's care was positive and they felt guided by the nursing team. Most of them would have been more active with guidance. Skin-to-skin care was appreciated and desired, but could become stressful if the conditions were not optimal.


Assuntos
Atitude Frente a Saúde , Estado Terminal , Pais , Adulto , Criança Hospitalizada , Feminino , França , Humanos , Recém-Nascido , Masculino , Inquéritos e Questionários
5.
Mucosal Immunol ; 8(3): 572-81, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25269707

RESUMO

Adherent-invasive Escherichia coli (AIEC), associated with Crohn's disease, are likely candidate contributory factors in the disease. However, signaling pathways involved in human intestinal mucosa innate host response to AIEC remain unknown. Here we use a 3D model of human intestinal mucosa explant culture to explore the effects of the AIEC strain LF82 on two innate immunity platforms, i.e., the inflammasome through evaluation of caspase-1 status, and NFκB signaling. We showed that LF82 bacteria enter and survive within a few intestinal epithelial cells and macrophages, without altering the mucosa overall architecture. Although 4-h infection with a Salmonella strain caused crypt disorganization, caspase-1 activation, and mature IL-18 production, LF82 bacteria were unable to activate caspase-1 and induce IL-18 production. In parallel, LF82 bacteria activated NFκB signaling in epithelial cells through IκBα phosphorylation, NFκBp65 nuclear translocation, and TNFα secretion. In addition, NFκB activation was crucial for the maintenance of epithelial homeostasis upon LF82 infection. In conclusion, here we decipher at the whole-mucosa level the mechanisms of the LF82-induced subversion of innate immunity that, by maintaining host cell integrity, ensure intracellular bacteria survival.


Assuntos
Doença de Crohn/microbiologia , Células Epiteliais/imunologia , Evasão da Resposta Imune , Imunidade Inata , Mucosa Intestinal/imunologia , Macrófagos/imunologia , Salmonella/imunologia , Caspase 1/genética , Caspase 1/imunologia , Doença de Crohn/genética , Doença de Crohn/imunologia , Doença de Crohn/patologia , Células Epiteliais/microbiologia , Regulação da Expressão Gênica , Humanos , Proteínas I-kappa B/genética , Proteínas I-kappa B/imunologia , Imunidade nas Mucosas , Inflamassomos/imunologia , Interleucina-18/genética , Interleucina-18/imunologia , Mucosa Intestinal/microbiologia , Macrófagos/microbiologia , Inibidor de NF-kappaB alfa , Fosforilação , Transdução de Sinais , Técnicas de Cultura de Tecidos , Fator de Transcrição RelA/genética , Fator de Transcrição RelA/imunologia , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/imunologia
6.
Pathol Biol (Paris) ; 61(5): 217-22, 2013 Oct.
Artigo em Francês | MEDLINE | ID: mdl-22841390

RESUMO

AIM OF THE STUDY: The French national surveillance program of multidrug-resistant bacteria (MDR) shows an increase of enterobacteriaceae-producing extended-spectrum beta-lactamases (ESBLE) incidence. The objectives of this study were to assess: the incidence of EBLSE in a large French university hospital between 2005 and 2010, and the difference of barrier precautions implementation between ESBL and other MDR. METHODS: The ESBLE incidence measure used data from the laboratory of bacteriology. The application of isolation and barrier precautions was analyzed from the MRB national surveillance data over a 3-year period from 2006 to 2008. Data were entered and analyzed using Epi Info software. The Chi(2) test was used for the comparison of proportions. RESULTS: The overall incidence of ESBLE was significantly higher in 2010 than in 2005 (0.20/1000 patients-days vs 0.03/1000 patients-days, respectively) (P<0.001). The same was observed for Escherichia coli incidence with rates ranging from 0.02/1000 patients-days in 2005 to 0.15/1000 patients-days in 2010. Isolation precautions for patients with EBLSE were applied in relation for most patients with MRB (ESBLE vs others), without significant difference. CONCLUSION: The surveillance programme of MRB showed a significant increase of ESBLE, especially for E. coli. Isolation and barrier precautions were used for most patients with MRB, including ESBLE.


Assuntos
Resistência a Múltiplos Medicamentos , Infecções por Enterobacteriaceae/epidemiologia , Infecções por Enterobacteriaceae/microbiologia , Enterobacteriaceae/enzimologia , Hospitais Universitários , beta-Lactamases/biossíntese , Infecção Hospitalar/microbiologia , Enterobacteriaceae/isolamento & purificação , Infecções por Enterobacteriaceae/tratamento farmacológico , Infecções por Escherichia coli/epidemiologia , França/epidemiologia , Humanos , Controle de Infecções , Isolamento de Pacientes
10.
Pathol Biol (Paris) ; 59(3): 151-6, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19481883

RESUMO

The prevalence of plasmid-mediated quinolone resistance (PMQR) determinants (qnrA, qnrB, qnrS, aac(6')-Ib-cr, and qepA) was investigated in a collection of 47 extended-spectrum ß-lactamase (ESBL) producing enterobacterial isolates with reduced susceptibility to fluoroquinolones, recovered at Nantes University hospital, in 2006. qnr, aac(6')-Ib-cr, and qepA genes were screened by PCR, and positive results were subsequently confirmed by sequencing. The epidemiological relationship between positive isolates was studied by pulsed-field gel electrophoresis (PFGE). qnr-positive isolates were analyzed for antimicrobial susceptibility and presence of mutations in the quinolone resistance-determining region (QRDR) of gyrA and parC genes. ESBL genes were characterized by PCR and sequencing. Conjugation experiments were performed to determine whether the qnr-carrying plasmids were self-transferable. Two Klebsiella pneumoniae isolates (4.3%), not clonally related, harboured a qnrS1 gene, whereas no qnrA- or qnrB-positive isolate was detected. The aac(6')-Ib-cr gene was detected in 11 Escherichia coli and one K. pneumoniae isolates. None of the 47 isolates carried the qepA gene. ESBLs associated with QnrS1 were CTX-M-14 and CTX-M-15. The CTX-M-15 producing isolate was highly resistant to fluoroquinolones and harboured three mutations in the QRDR and two PMQR determinants (qnrS1 and aac(6')-Ib-cr). The CTX-M-14-producing isolate exhibited reduced susceptibility or resistance to fluoroquinolones without resistance to nalidixic acid. This strain harboured only a qnr gene on a single 170 kb transferable plasmid, without any mutation in the QRDR. In conclusion, our study showed that aac(6')-Ib-cr gene had occurred in multiclonal ESBL-producing enterobacterial isolates collected at Nantes University hospital in 2006, with a higher prevalence than qnr genes.


Assuntos
Antibacterianos/farmacologia , Proteínas de Bactérias/genética , Farmacorresistência Bacteriana Múltipla , Infecções por Enterobacteriaceae/microbiologia , Enterobacteriaceae/efeitos dos fármacos , Quinolonas/farmacologia , Fatores R/isolamento & purificação , Conjugação Genética , DNA Girase/genética , DNA Topoisomerase IV/genética , DNA Bacteriano/genética , Farmacorresistência Bacteriana Múltipla/genética , Eletroforese em Gel de Campo Pulsado , Enterobacteriaceae/enzimologia , Enterobacteriaceae/isolamento & purificação , Infecções por Enterobacteriaceae/epidemiologia , França/epidemiologia , Hospitais Universitários , Humanos , Reação em Cadeia da Polimerase , Prevalência , Fatores R/genética , Análise de Sequência de DNA , Especificidade da Espécie , Resistência beta-Lactâmica/genética , beta-Lactamases/genética
11.
Ann Fr Anesth Reanim ; 30(1): 61-3, 2011 Jan.
Artigo em Francês | MEDLINE | ID: mdl-21185686

RESUMO

We present the case of a 34-year-old woman who developed, in postpartum period of an uncomplicated pregnancy, a thunderclap headache with visual disturbance associated with a severe arterial hypertension. Both clinical evolution and cerebral imaging including angio-MR confirmed the diagnosis of postpartum reversible vasoconstriction syndrome. One of the leading causes of this syndrome is the use of vasoactive drugs as it was observed in the case of this patient. It is important to consider this syndrome in the differential diagnosis in patients presenting with headache in the postpartum period.


Assuntos
Angiografia Cerebral/efeitos adversos , Transtornos da Cefaleia Primários/etiologia , Angiografia por Ressonância Magnética/efeitos adversos , Adulto , Constrição Patológica/patologia , Eclampsia/fisiopatologia , Feminino , Humanos , Imageamento por Ressonância Magnética , Período Pós-Parto , Gravidez , Fumar , Vasoconstrição/fisiologia , Transtornos da Visão/etiologia
12.
Eur J Clin Microbiol Infect Dis ; 30(3): 401-6, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21063742

RESUMO

In the past decade, the number of couples consulting an assisted reproductive techniques (ART) center for infertility has increased in most European countries. In France, sperm bacterial examination must be performed every 6 months in couples undergoing in vitro fertilization (IVF) cycles, according to 2010 French ART Guidelines. The aim of this study was to analyze the results from such samples at Nantes University Hospital and to assess their potential value for infertile couples undergoing ART cycles. Between 2003 and 2008, semen cultures performed were analyzed according to bacterial enumeration, type and number of bacterial species, and their antibiotic resistance profile. A total of 14,119 semen cultures were performed, showing an annual increase of 45% from the start to the end of the study. The proportion of positive semen cultures was stable throughout the study period (40 to 45%). Many bacterial species were considered as contaminants (coagulase-negative staphylococci, alpha-hemolytic streptococci). For pathogen agents (in most cases, Enterobacteriaceae), the antibiotic resistance profile revealed mostly a susceptible phenotype. Finally, every positive bacterial result had direct consequences on the IVF cycle management, with subsequent reinforced advice on the hygiene procedure before sample collection and/or antibiotics prescription.


Assuntos
Bactérias/isolamento & purificação , Fertilização in vitro , Sêmen/microbiologia , Bactérias/classificação , Farmacorresistência Bacteriana , França , Humanos , Infertilidade/terapia , Masculino , Testes de Sensibilidade Microbiana , Estudos Retrospectivos
13.
J Clin Microbiol ; 49(1): 380-2, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21068273

RESUMO

Twelve group B Streptococcus (GBS) prosthetic joint infection (PJI) cases are reported. The mean patient age was 55 years. Eleven infections were caused by GBS alone. The associated isolates belonged to phylogenetic lineages different from those that cause neonatal meningitis. The clinical outcome was favorable for the eight patients for whom follow-up data were available.


Assuntos
Osteoartrite/microbiologia , Osteoartrite/patologia , Infecções Relacionadas à Prótese/microbiologia , Infecções Relacionadas à Prótese/patologia , Infecções Estreptocócicas/microbiologia , Infecções Estreptocócicas/patologia , Streptococcus agalactiae/classificação , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Tipagem Molecular , Filogenia , Streptococcus agalactiae/genética , Streptococcus agalactiae/isolamento & purificação , Resultado do Tratamento
14.
Eur J Clin Microbiol Infect Dis ; 29(6): 745-7, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20372955

RESUMO

The aim of the present study was to compare the performance of the new VITEK2 AST-P551 card with the cefoxitin disk diffusion method for the daily detection of methicillin resistance with a high number of Staphylococcus aureus clinical isolates. Detection of the PBP2a protein or mecA gene was performed for each discordant case. Seventy (3.3%) isolates out of 2,107 clinical strains showed discordant results, two very major errors, four major errors and 64 minor errors. Fifty-nine (84%) discordant results were resolved, with a final overall agreement of 99.5%. Eleven (0.5%) strains remained discordant (minor error [mE]). Four of 370 MRSA strains were misclassified as susceptible in daily practice by the cefoxitin disk diffusion method. All of these strains were resistant to aminoglycosides and/or fluoroquinolones. The VITEK2 system is highly reliable for methicillin resistance detection at the routine level. Oxacillin-susceptible classified clinical strains with associated resistance patterns required attention.


Assuntos
Antibacterianos/farmacologia , Cefoxitina , Resistência a Meticilina , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Oxacilina/farmacologia , Infecções Estafilocócicas/microbiologia , Proteínas de Bactérias/análise , Proteínas de Bactérias/genética , Erros de Diagnóstico/estatística & dados numéricos , Humanos , Testes de Sensibilidade Microbiana/métodos , Proteínas de Ligação às Penicilinas/análise , Sensibilidade e Especificidade
16.
Med Mal Infect ; 39(12): 886-90, 2009 Dec.
Artigo em Francês | MEDLINE | ID: mdl-19345530

RESUMO

OBJECTIVE: The purpose of this study was to describe the characteristics of patients hospitalized for a peritonsillar abscess over a 1-year period and to evaluate the proportion of patients exposed to anti-inflammatory and antibiotic drugs before hospitalization. DESIGN: Adult patients hospitalized in the ENT department at the Nantes University Hospital were included in the study during 2006. Data related to prior use of anti-inflammatory and antibiotic drugs, microbiology and treatment was analyzed. RESULTS: Thirty-four patients were included in the study, 20 (59%) and 21 (62%) patients had been previously exposed to anti-inflammatory and antibiotic drugs, respectively. Half of the patients had received antibiotics despite the negativity of the rapid screening test. All diagnoses were made on pus examination after aspiration. Tonsillectomy was performed only in two cases. A total of 21 bacterial isolates (13 anaerobic and 9 aerobic) were identified. Single bacterial isolates were recovered in 8 infections. The most frequent bacteria were Streptococcus, Fusobacterium, and Prevotella. CONCLUSIONS: Many patients were exposed to both anti-inflammatory and antibiotic drugs, which did not prevent the peritonsillar abscess.


Assuntos
Antibacterianos/uso terapêutico , Anti-Inflamatórios/uso terapêutico , Abscesso Peritonsilar/epidemiologia , Adolescente , Adulto , Idoso , Estudos de Coortes , Terapia Combinada , Suscetibilidade a Doenças , Uso de Medicamentos/estatística & dados numéricos , Diagnóstico Precoce , Feminino , França/epidemiologia , Hospitais Universitários/estatística & dados numéricos , Humanos , Pacientes Internados/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Abscesso Peritonsilar/tratamento farmacológico , Abscesso Peritonsilar/microbiologia , Abscesso Peritonsilar/prevenção & controle , Abscesso Peritonsilar/cirurgia , Faringite/tratamento farmacológico , Faringite/epidemiologia , Faringite/microbiologia , Estudos Retrospectivos , Infecções Estreptocócicas/diagnóstico , Infecções Estreptocócicas/tratamento farmacológico , Infecções Estreptocócicas/epidemiologia , Tonsilectomia , Tonsilite/tratamento farmacológico , Tonsilite/epidemiologia , Tonsilite/microbiologia , Resultado do Tratamento , Adulto Jovem
18.
Pathol Biol (Paris) ; 57(3): e23-8, 2009 May.
Artigo em Francês | MEDLINE | ID: mdl-18456433

RESUMO

Since 2000, a resurgence of syphilis cases was observed in France and, particularly, in Paris area. The aim of this study was to evaluate the evolution of syphilis prevalence in Nantes area and its impact on our laboratory activity. Between 1999 and 2006, serological tests for syphilis performed at the laboratory were analysed according to the results of these tests, the age and patient sex and the wards. We treated about 32,000 serological tests, over an eight-year period. The number of tests increased by 7.5% per year and patients with a positive result were multiplied by three. These patients were men for 78%, with an average age of 43.4 years. The serological tests providing positive results were in general from two sectors, the anonymous and free detection center and the internal medicine ward and infectious diseases unit. Our study highlighted a strong increase in the number of positive tests, since 2001, with a clear orientation towards a sex male ratio in our area. This inclination currently did not show any decrease, at the opposite to what was observed by the InVS in Paris area.


Assuntos
Sífilis/diagnóstico , Adulto , Feminino , França/epidemiologia , Hospitais Universitários/estatística & dados numéricos , Humanos , Masculino , Paris/epidemiologia , Prevalência , Estudos Retrospectivos , Testes Sorológicos/métodos , Caracteres Sexuais , Sífilis/epidemiologia
19.
Arch Ital Biol ; 145(3-4): 251-62, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18075119

RESUMO

In psychophysics and physiology, it is well established that lateral interactions are crucial mechanisms to constrain response normalization and contextual modulations. To study the cortical mechanisms involved in the contextual modulation of the behavioral contrast response function, we compared in behaving monkeys the Ocular Following Response (OFR) to V1 population activity measured using Optical Imaging of Voltage-Sensitive Dyes (VSD). If contrast response functions (CRF) to a simple local stimulus are similar in V1 and in the OFR, lateral interaction leads however to quite different modulation at those two levels. At the behavioural level, contrast response function is strongly suppressed by lateral interactions, and this suppression is stronger for higher contrasts. In V1, we showed a slow dynamic of facilitation for low contrasts integration and a fast suppression operating on high contrasts. These modulatory interactions influence differently the contrast response functions, interrupting the dynamic increase of contrast sensitivity in OFR, but not in V1 response. The temporal properties of those effects lead us to hypothesize that horizontal and feedback connectivity have differential effect on low and high contrasts integration in V1. V1 provides then an input to MT whose contextual dependency is not totally determined and must be refined before affecting the behavioural OFR.


Assuntos
Sensibilidades de Contraste/fisiologia , Movimentos Oculares/fisiologia , Fixação Ocular/fisiologia , Desempenho Psicomotor/fisiologia , Retina/fisiologia , Córtex Visual/fisiologia , Animais , Eletrofisiologia/instrumentação , Eletrofisiologia/métodos , Macaca mulatta , Neurônios/fisiologia , Óptica e Fotônica/instrumentação , Estimulação Luminosa , Tempo de Reação/fisiologia , Transmissão Sináptica/fisiologia , Campos Visuais/fisiologia , Vias Visuais/fisiologia
20.
Dev Biol (Basel) ; 126: 219-26; discussion 326-7, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17058498

RESUMO

Chlamydophila abortus and Coxiella burnetii are one of the major pathogens implicated in abortion in cattle. Their characteristic of obligate intracellular bacteria, and of zoonotic agents, makes their culture difficult in diagnostic laboratories, and the traditional tools of diagnosis (detection of sera antibodies by ELISA, Stamp's coloration) encounter specificity, sensitivity and interpretability limits. Individual PCR have recently been developed. Nevertheless, their income/cost is a limiting factor for breeders. As the symptoms are not specific, the request for analysis often concerns the two valences. Consequently, the development and the validation of an internal multiplex PCR appears to be a suitable solution.


Assuntos
Doenças dos Bovinos/diagnóstico , Doenças dos Bovinos/microbiologia , Infecções por Chlamydophila/veterinária , Chlamydophila/isolamento & purificação , Coxiella burnetii/isolamento & purificação , Reação em Cadeia da Polimerase/métodos , Febre Q/veterinária , Aborto Animal/microbiologia , Animais , Bovinos , Chlamydophila/genética , Infecções por Chlamydophila/diagnóstico , Infecções por Chlamydophila/microbiologia , Coxiella burnetii/genética , Reação em Cadeia da Polimerase/veterinária , Febre Q/diagnóstico , Febre Q/microbiologia , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
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