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991.
Karine Silva Mariely Lima André Santos-Magalhães Carla Fafiães Liliana de Sousa 《Anthrozo?s》2019,32(1):23-33
The inclusion of animals and robots in therapeutic interventions for Autism Spectrum Disorder (ASD) has become more common. This study provides a first comparison between the potential of living versus robotic dogs to elicit social communication behavior and regulated emotional responses in individuals with ASD. Ten children and thirteen adults with ASD and severe lan- guage delay were tested for appropriate social communication behavior and cardiac autonomic functioning during a planned, structured interaction with an experimenter alone (no-stimulus condition), an experimenter accompanied by a living dog (dog condition), and an experimenter accompanied by a robotic dog (robot condition). A within-subjects design was followed to expose all participants to all three experimental conditions. Overall, participants (children and adults) showed a higher percentage of appropriate social behaviors in Living and Robotic Dogs as Elicitors of Social Communication Behavior and Regulated Emotional?…?the dog and the robot conditions than in the no-stimulus condition. In children, the living dog was more effective than the robotic dog in promoting social communication behavior. In adults, no such difference was found between the dog and the robot condition. Only the dog appeared to elicit a positive effect in cardiac autonomic functioning by increasing heart rate variability (HRV) and buffer- ing the decrease in parasympathetic activity due to interaction with the experimenter. The data are preliminary but relevant and warrant replication in larger-scale studies. 相似文献
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994.
Ahmad Reza Meamar Karine Guyot Gabriela Certad Eduardo Dei-Cas Mino Mohraz Mehdi Mohebali Kazem Mohammad Amir Ali Mehbod Sasan Rezaie Mostafa Rezaian 《Applied microbiology》2007,73(3):1033-1035
Isolates of Cryptosporidium spp. from human and animal hosts in Iran were characterized on the basis of both the 18S rRNA gene and the Laxer locus. Three Cryptosporidium species, C. hominis, C. parvum, and C. meleagridis, were recognized, and zoonotically transmitted C. parvum was the predominant species found in humans. 相似文献
995.
Integrated Real-Time PCR for Detection and Monitoring of Legionella pneumophila in Water Systems 下载免费PDF全文
Diaraf Farba Yaradou Sylvie Hallier-Soulier Sophie Moreau Florence Poty Yves Hillion Monique Reyrolle Janine Andr Gabriel Festoc Karine Delabre Franois Vandenesch Jerome Etienne Sophie Jarraud 《Applied microbiology》2007,73(5):1452-1456
We evaluated a ready-to-use real-time quantitative Legionella pneumophila PCR assay system by testing 136 hot-water-system samples collected from 55 sites as well as 49 cooling tower samples collected from 20 different sites, in parallel with the standard culture method. The PCR assay was reproducible and suitable for routine quantification of L. pneumophila. An acceptable correlation between PCR and culture results was obtained for sanitary hot-water samples but not for cooling tower samples. We also monitored the same L. pneumophila-contaminated cooling tower for 13 months by analyzing 104 serial samples. The culture and PCR results were extremely variable over time, but the curves were similar. The differences between the PCR and culture results did not change over time and were not affected by regular biocide treatment. This ready-to-use PCR assay for L. pneumophila quantification could permit more timely disinfection of cooling towers. 相似文献
996.
The cyclin-dependent kinase inhibitor Dacapo promotes replication licensing during Drosophila endocycles 下载免费PDF全文
Hong A Narbonne-Reveau K Riesgo-Escovar J Fu H Aladjem MI Lilly MA 《The EMBO journal》2007,26(8):2071-2082
The endocycle is a developmentally programmed variant cell cycle in which cells undergo repeated rounds of DNA replication with no intervening mitosis. In Drosophila, the endocycle is driven by the oscillations of Cyclin E/Cdk2 activity. How the periodicity of Cyclin E/Cdk2 activity is achieved during endocycles is poorly understood. Here, we demonstrate that the p21(cip1)/p27(kip1)/p57(kip2)-like cyclin-dependent kinase inhibitor (CKI), Dacapo (Dap), promotes replication licensing during Drosophila endocycles by reinforcing low Cdk activity during the endocycle Gap-phase. In dap mutants, cells in the endocycle have reduced levels of the licensing factor Double Parked/Cdt1 (Dup/Cdt1), as well as decreased levels of chromatin-bound minichromosome maintenance (MCM2-7) complex. Moreover, mutations in dup/cdt1 dominantly enhance the dap phenotype in several polyploid cell types. Consistent with a reduced ability to complete genomic replication, dap mutants accumulate increased levels of DNA damage during the endocycle S-phase. Finally, genetic interaction studies suggest that dap functions to promote replication licensing in a subset of Drosophila mitotic cycles. 相似文献
997.
Exosomes are part of the family of "bioactive vesicles" and appear to be involved in distal communications between cells. They vehiculate bioactive lipids and lipolytic enzymes and their biogenesis require specific lipids and a membrane reorganisation. Their biogenesis pathway could be a way to secrete enzymes involved in lipid signalling and to generate "particulate agonists". However, this pathway seems also to be used by pathogens such as HIV. This review will consider several aspects of lipidomics studies which might help to understand the fate and role of these fascinating vesicles. 相似文献
998.
Beauséjour A Houde V Bibeau K Gaudet R St-Louis J Brochu M 《American journal of physiology. Regulatory, integrative and comparative physiology》2007,293(4):R1657-R1665
Sodium supplementation given for 1 wk to nonpregnant rats induces changes that are adequate to maintain renal and circulatory homeostasis as well as arterial blood pressure. However, in pregnant rats, proteinuria, fetal growth restriction, and placental oxidative stress are observed. Moreover, the decrease in blood pressure and expansion of circulatory volume, normally associated with pregnancy, are prevented by high-sodium intake. We hypothesized that, in these pregnant rats, a loss of the balance between prooxidation and antioxidation, particularly in kidneys and heart, disturbs the normal course of pregnancy and leads to manifestations such as gestational hypertension. We thus investigated the presence of oxidative/nitrosative stress in heart and kidneys following high-sodium intake in pregnant rats. Markers of this stress [8-isoprostaglandin F(2alpha) (8-iso-PGF(2alpha)) and nitrotyrosine], producer of nitric oxide [nitric oxide synthases (NOSs)], and antioxidants [superoxide dismutase (SOD) and catalase] were measured. Then, molecules (Na(+)-K(+)-ATPase and aconitase) or process [apoptosis (Bax and Bcl-2), inflammation (monocyte chemoattractant protein-1, connective tissue growth factor, and TNF-alpha)] susceptible to free radicals was determined. In kidneys from pregnant rats on 1.8% NaCl-water, NOSs, apoptotic index, and nitrotyrosine expression were increased, whereas Na(+)-K(+)-ATPase mRNA and activity were decreased. In the left cardiac ventricle of these rats, heightened nitrotyrosine, 8-iso-PGF(2alpha), and catalase activity together with reduced endothelial NOS protein expression and SOD and aconitase activities were observed. These findings suggest that oxidative/nitrosative stress in kidney and left cardiac ventricle destabilizes the normal course of pregnancy and could lead to gestational hypertension. 相似文献
999.
A real-time PCR assay using 136F/211R primers and 161T TaqMan probe for the detection and quantification of Aphanomyces euteiches in soil is presented. The specificity of primers was tested on 105 different A. euteiches isolates, mainly from France. A calibration curve was established with a plasmid pHS1 resulting from the target region cloned into the pCR4 Topo vector (Invitrogen). The target copy number was evaluated and was constant whatever the isolate. A DNA-based method was able to discriminate between different artificial infestation levels in soil with small SDs thus validating the relevance of the extraction and amplification method in soil samples. Furthermore, a good correlation was observed between inoculum quantity in soil estimated by qPCR and root rot severity in plant evaluated by bioassays. These steps are essential when considering the feasibility of using a DNA-based method as a fast and accurate way to evaluate inoculum quantity in soil. 相似文献
1000.
Mutations in alpha-tubulin cause abnormal neuronal migration in mice and lissencephaly in humans 总被引:7,自引:0,他引:7
Keays DA Tian G Poirier K Huang GJ Siebold C Cleak J Oliver PL Fray M Harvey RJ Molnár Z Piñon MC Dear N Valdar W Brown SD Davies KE Rawlins JN Cowan NJ Nolan P Chelly J Flint J 《Cell》2007,128(1):45-57
The development of the mammalian brain is dependent on extensive neuronal migration. Mutations in mice and humans that affect neuronal migration result in abnormal lamination of brain structures with associated behavioral deficits. Here, we report the identification of a hyperactive N-ethyl-N-nitrosourea (ENU)-induced mouse mutant with abnormalities in the laminar architecture of the hippocampus and cortex, accompanied by impaired neuronal migration. We show that the causative mutation lies in the guanosine triphosphate (GTP) binding pocket of alpha-1 tubulin (Tuba1) and affects tubulin heterodimer formation. Phenotypic similarity with existing mouse models of lissencephaly led us to screen a cohort of patients with developmental brain anomalies. We identified two patients with de novo mutations in TUBA3, the human homolog of Tuba1. This study demonstrates the utility of ENU mutagenesis in the mouse as a means to discover the basis of human neurodevelopmental disorders. 相似文献