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91.
Catarina S. Nunes David A. Ferreira Luís Antunes Francisco Lobo Isabel A. Santos Pedro Amorim 《Journal of clinical anesthesia》2009,21(1):3-8
Study ObjectiveTo investigate whether a patient's propofol effect-site concentration at return to consciousness (ROC) was related to the propofol effect-site concentration at loss of consciousness (LOC) and to patients' individual demographic parameters.DesignProspective study.SettingOperating room.Patients31 ASA physical status I and II neurosurgical patients with Glasgow Coma Score > 15, and scheduled to receive total intravenous anesthesia with effect-site target controlled infusion (TCI) of propofol and remifentanil.InterventionsA constant propofol infusion was administered until LOC. At LOC, remifentanil started with a plasma concentration target of 2.5 ng mL?1.Main ResultsPropofol concentration at LOC was 4.9 ± 1 μg mL?1. At ROC, propofol and remifentanil concentrations were 1.16 ± 0.3 μg mL?1 and 3.41 ± 1.5 ng mL?1. Significant correlation was observed between propofol concentrationa at ROC and LOC, between propofol concentration at ROC and patient age (48.7 ± 15 yrs), and between propofol concentrations at ROC and LOC, divided by patient's age.ConclusionsThe correlation between propofol concentrations at ROC and LOC was improved by inclusion of patient age data. 相似文献
92.
Robin Baurs Nicolas Benguigui Michel-Ange Amorim Heiko Hecht 《Journal of neuroscience methods》2009,184(1):48-53
The use of virtual reality is nowadays common in many studies in the field of human perception and movement control, particularly in interceptive actions. However, the ecological validity of the simulation is often taken for granted without having been formally established. If participants were to perceive the real situation and its virtual equivalent in a different fashion, the generalization of the results obtained in virtual reality to real life would be highly questionable. We tested the ecological validity of virtual reality in this context by comparing the timing of interceptive actions based upon actually falling objects and their simulated counterparts. The results show very limited differences as a function of whether participants were confronted with a real ball or a simulation thereof. And when present, such differences were limited to the first trial only. This result validates the use of virtual reality when studying interceptive actions of accelerated stimuli. 相似文献
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95.
de Paula Sabino A Guimarães DA Ribeiro DD Paiva SG Sant'Ana Dusse LM das Graças Carvalho M Fernandes AP 《Journal of thrombosis and thrombolysis》2007,24(3):261-266
Introduction Of the inherited thrombophilias, the Factor V Leiden (FVL) and the prothrombin mutant (FII G20210A) are associated with increased
risk of venous thromboembolism (VTE). The C677T mutation of the methylenetetrahydrofolate reductase gene, which may lead to
hyperhomocysteinemia, is also considered a risk factor for VTE in some studies. However, the frequency of these genetic risk
factors may vary significantly among different populations.
Material and methods The FVL, FII G20210A and C677T mutations were investigated by PCR-RFLP in 275 young VTE Brazilian patients as well as in 324
biologically unrelated individuals selected to compose the control group.
Results The C677T mutation in the MTHFR gene was detected in 135 (49.1%) patients, of which 117 (42.5%) were identified as heterozygous
and 18 (6.5%) as homozygous. The G20210A mutation was detected in 14 (5.1%) patients in heterozygosis. In both cases, no significant
difference was observed when these results were compared to the frequencies observed in the control group. FVL was detected
in heterozygosis in 19 (6.9%) patients, corresponding to a significantly increased frequency when compared to that observed
for the control group (1.2%) (OR 5.9; 95% CI 2.08–16.79; p < 0.001).
Conclusions The data indicated that FVL is significantly associated with VTE among young Brazilian patients, but also supported previous
evidence that VTE is a multi-factorial disease, resulting from the interaction of genetic and acquired risk factors. 相似文献
96.
Benoît Fourre Brice Isableu Delphine Bernardin Marc Gueguen Guillaume Giraudet Nicolas Vuillerme Christopher Pagano Michel-Ange Amorim 《Neuroscience letters》2009
We examined to which extent proprioceptive information involved in the perception of subjective vertical corresponded to mechanical mass-based axes of the body. Blindfolded subjects (n = 14) estimated their subjective vertical in conditions of deviation of the centre of mass (CM) of (1) the head–trunk unit or (2) the head segment alone. Verticality estimates (provided in a haptic modality) were significantly altered by the deviation of the head–trunk CM (by either 4° or 7°), indicating that the subjects used mass-based proprioceptive information stemming from the trunk. Modifying the perception of body orientation by shifting the trunk CM sideways while keeping the body vertical, deviates the subjective vertical towards the opposite side in a similar way to the so-called ‘E-effect’. The induced deviations of head CM (9.33°) did not affect the subjective vertical, suggesting that when the balance of the body is not threatened, proprioceptive or vestibular information is prioritized to estimate gravitational direction. 相似文献
97.
Antimalarial activity of betulinic acid and derivatives in vitro against Plasmodium falciparum and in vivo in P. berghei-infected mice 总被引:1,自引:1,他引:0
Matheus Santos de Sá José Fernando Oliveira Costa Antoniana Ursine Krettli Mariano Gustavo Zalis Gabriela Lemos de Azevedo Maia Ivana Maria Fechine Sette Celso de Amorim Camara José Maria Barbosa Filho Ana Maria Giulietti-Harley Ricardo Ribeiro dos Santos Milena Botelho Pereira Soares 《Parasitology research》2009,105(1):275-279
Malaria is one of the most important tropical diseases and mainly affects populations living in developing countries. Reduced
sensitivity of Plasmodium sp. to formerly recommended antimalarial drugs places an increasing burden on malaria control programs as well as on national
health systems in endemic countries. The present study aims to evaluate the antimalarial activity of betulinic acid and its
derivative compounds, betulonic acid, betulinic acid acetate, betulinic acid methyl ester, and betulinic acid methyl ester
acetate. These substances showed antiplasmodial activity against chloroquine-resistant Plasmodium falciparum parasites in vitro, with IC50 values of 9.89, 10.01, 5.99, 51.58, and 45.79 μM, respectively. Mice infected with Plasmodium berghei and treated with betulinic acid acetate had a dose-dependent reduction of parasitemia. Our results indicate that betulinic
acid and its derivative compounds are candidates for the development of new antimalarial drugs. 相似文献
98.
Lúcia Inês Macedo-Souza Fernando Kok † Silvana Santos Luciana Licinio Karina Lezirovitz Natale Cavaçana Clarissa Bueno Simone Amorim ré Pessoa Zodja Graciani Áurea Ferreira Abdísio Prazeres Áurea Nogueira de Melo Paulo Alberto Otto Mayana Zatz 《Annals of human genetics》2009,73(3):382-387
SPOAN is an autosomal recessive neurodegenerative disorder which was recently characterized by our group in a large inbred Brazilian family with 25 affected individuals. This condition is clinically defined by: 1. congenital optic atrophy; 2. progressive spastic paraplegia with onset in infancy; and 3. progressive motor and sensory axonal neuropathy. Overall, we are now aware of 68 SPOAN patients (45 females and 23 males, with age ranging from 5 to 72 years), 44 of which are presented here for the first time. They were all born in the same geographic micro region. Those 68 patients belong to 43 sibships, 40 of which exhibit parental consanguinity. Sixty-one patients were fully clinically evaluated and 64 were included in the genetic investigation. All molecularly studied patients are homozygotes for D11S1889 at 11q13. This enabled us to reduce the critical region for the SPOAN gene from 4.8 to 2.3 Mb, with a maximum two point lod score of 33.2 (with marker D11S987) and of 27.0 (with marker D11S1889). Three genes located in this newly defined critical region were sequenced, but no pathogenic mutation was detected. The gene responsible for SPOAN remains elusive. 相似文献
99.
Sofia Quental Alfredo Gusmão Pilar Rodríguez-Pombo Magdalena Ugarte Laura Vilarinho António Amorim Maria J. Prata 《Annals of human genetics》2009,73(3):298-303
Maple syrup urine disease (MSUD) is a rare autosomal recessive disorder of branched-chain amino acid metabolism. In the context of the wide mutational spectrum known for this disease, a few common mutations have been described in populations where founder effects played a major role in modeling diversities. In Portugal, for instance, a high proportion of patients are of Gypsy origin and all share the same mutation (c.117delC-α; p.R40GfsX23), causing the neonatal severe form of MSUD. In this study, we used four microsatellite markers closely flanking the BCKDHA gene (E1α protein) to demonstrate that c.117delC-α is a founder mutation responsible for the high incidence of the disorder among Portuguese Gypsies. These results are of medical relevance since carrier tests and prenatal diagnosis can be offered to families at risk, particularly because the carrier frequency of c.117delC-α was estimated at 1.4% among the healthy Portuguese Gypsies from the South of the country. Finally we present evidence that the genomic region of the BCKDHA gene where c.117delC-α is located is likely a mutational hotspot, since recurrence of c.117delC-α was observed in two distinct population groups. 相似文献
100.
Barreto do Carmo MB Neves Santos D Alves Ferreira Amorim LD Fiaccone RL Souza da Cunha S Cunha Rodrigues L Barreto ML 《Social psychiatry and psychiatric epidemiology》2009,44(5):416-420