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71.
Vianna FS Lopez-Camelo JS Leite JC Sanseverino MT Dutra Mda G Castilla EE Schüler-Faccini L 《PloS one》2011,6(7):e21735
The thalidomide tragedy of the 1960s resulted in thousands of children being born with severe limb reduction defects (LRD), among other malformations. In Brazil, there are still babies born with thalidomide embryopathy (TE) because of leprosy prevalence, availability of thalidomide, and deficiencies in the control of drug dispensation. Our objective was to implement a system of proactive surveillance to identify birth defects compatible with TE. Along one year, newborns with LRD were assessed in the Brazilian hospitals participating in the Latin-American Collaborative Study of Congenital Malformations (ECLAMC). A phenotype of LRD called thalidomide embryopathy phenotype (TEP) was established for surveillance. Children with TEP born between the years 2000-2008 were monitored, and during the 2007-2008 period we clinically investigated in greater detail all cases with TEP (proactive period). The period from 1982 to 1999 was defined as the baseline period for the cumulative sum statistics. The frequency of TEP during the surveillance period, at 3.10/10,000 births (CI 95%: 2.50-3.70), was significantly higher than that observed in the baseline period (1.92/10,000 births; CI 95%: 1.60-2.20), and not uniformly distributed across different Brazilian regions. During the proactive surveillance (2007-2008), two cases of suspected TE were identified, although the two mothers had denied the use of the drug during pregnancy. Our results suggest that TEP has probably increased in recent years, which coincides with the period of greater thalidomide availability. Our proactive surveillance identified two newborns with suspected TE, proving to be a sensitive tool to detect TE. The high frequency of leprosy and the large use of thalidomide reinforce the need for a continuous monitoring of TEP across Brazil. 相似文献
72.
Jorge H. Medina María Laura Novas† Eduardo De Robertis† 《Journal of neurochemistry》1983,41(3):703-709
Abstract: This study was designed to analyze possible differences in the binding of [3H]flunitrazepam ([3H]FNZP) and [3H]ethyl - β - carboline - 3 - carboxylate ([3H]β-CCE), to rat brain membranes, in various experimental conditions. In cerebral cortex, hippocampus, cerebellum, and orain stem the number of binding sites for [3H]β-CCE was higher than for [3H]FNZP; both were displaced by clonazepam. Until the 7th day of postnatal brain development the numbers of [3H]FNZP and [3H]β-CCE sites were equivalent; but later on, the β-carboline sites increased to a higher level. Noradrenergic denervation by 6-hydroxydopamine was followed in the hippocampal formation. Already after 2 days, there was a decrease in [3H]FNZP sites, which reached 70% of control after 14 days. Similar results were obtained with DSP-4 denervation. This change was only in Bmax and not in KD, In contrast, the [3H]β-CCE sites did not change with denervation. Neonatal injection of l - 2,4,5 - trihydroxyphenylalamine or DSP-4 produced in the adult a decrease in [3H]FNZP sites in the cerebral cortex, in parallel with the noradrenergic denervation. On the other hand, there was an increase in the cerebellum and brain stem, in correspondence with the hyperinnervation by sprouting. In these rats, the number of sites for [3H]β-CCE did not change in the different brain regions. With 0.1% Triton X-100, applied to synaptosomal membranes, [3H]FNZP binding was reduced by 35%, while that of [3H]β-CCE was not significantly changed. These results suggest that there is heterogeneity of binding sites for benzodiazepine receptors in rat brain. A tentative interpretation of the experiments involving noradrenergic denervation and hyperinnervation, as well as those with Triton X-100, is that [3H]FNZP binds to pre- and postsynaptic receptors, while [3H]β-CCE binds mainly to postsynaptic benzodiazepine receptors. 相似文献
73.
Carvalho JE Gomes FR Navas CA 《Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology》2008,178(4):447-456
Anuran amphibians exhibit different patterns of energy substrate utilization that correlate with the intensity of vocal and
locomotor activities. Given the remarkable differences among species in breeding and feeding strategies, and the different
ways energy is used in the whole animal, the suggested correlations between calling and locomotor behavior and the level of
energy substrates in the muscles responsible for such activities are more complex than previously reported. We explored the
relationships between calling and locomotor behavior and energy supply to trunk and hindlimb muscles, respectively, within
the ecologically diverse tree-frog genus Scinax. Specifically, we measured the relative amount of carbohydrates and lipids in these two groups of muscles, and in the liver
of three species of Scinax that differ in vocal and locomotor performance, and compared our results with those of two other species for which comparable
data are available. We also compared the contents of lipids and carbohydrates of conspecific males collected at the beginning
and after 4 h of calling activity. The stomach content to potential feeding opportunities across species was also assessed
in both groups of males. Scinax hiemalis and S. rizibilis exhibit comparatively low and episodic calling during long periods of activity whereas S. crospedospilus calls at higher rates over shorter periods. Male S. hiemalis had highest levels of trunk muscle glycogen followed by those of S. rizilbilis and S. crospedospilus, respectively. There was no correlation between total lipid content in trunk muscle and calling rate among different species,
suggesting that other metabolic aspects may be responsible for the energetic support for vocal activity. The levels of lipids
and carbohydrates in trunk and hindlimb muscles and liver of males collected at the beginning and 4 h into the calling period
were similar across species, so the extent of energetic reserves does not appear to constrain vocal or locomotor activity.
Finally, we found exceptionally high levels of carbohydrates and lipids in the liver of S. rizibilis, a trait perhaps related to a long and demanding breeding period. 相似文献
74.
An analysis of determinants of amino acids substitution rates in bacterial proteins 总被引:14,自引:0,他引:14
The variation of amino acid substitution rates in proteins depends on several variables. Among these, the protein's expression level, functional category, essentiality, or metabolic costs of its amino acid residues may play an important role. However, the relative importance of each variable has not yet been evaluated in comparative analyses. To this aim, we made regression analyses combining data available on these variables and on evolutionary rates, in two well-documented model bacteria, Escherichia coli and Bacillus subtilis. In both bacteria, the level of expression of the protein in the cell was by far the most important driving force constraining the amino acids substitution rate. Subsequent inclusion in the analysis of the other variables added little further information. Furthermore, when the rates of synonymous substitutions were included in the analysis of the E. coli data, only the variable expression levels remained statistically significant. The rate of nonsynonymous substitution was shown to correlate with expression levels independently of the rate of synonymous substitution. These results suggest an important direct influence of expression levels, or at least codon usage bias for translation optimization, on the rates of nonsynonymous substitutions in bacteria. They also indicate that when a control for this variable is included, essentiality plays no significant role in the rate of protein evolution in bacteria, as is the case in eukaryotes. 相似文献
75.
Kátia Regina da Silva Roberto Costa Elizabeth Sartori Crevelari Marianna Sobral Lacerda Caio Marcos de Moraes Albertini Martino Martinelli Filho José Eduardo Santana Jo?o Ricardo Nickenig Vissoci Ricardo Pietrobon Jacson V. Barros 《PloS one》2013,8(7)
Background
The ability to apply standard and interoperable solutions for implementing and managing medical registries as well as aggregate, reproduce, and access data sets from legacy formats and platforms to advanced standard formats and operating systems are crucial for both clinical healthcare and biomedical research settings.Purpose
Our study describes a reproducible, highly scalable, standard framework for a device registry implementation addressing both local data quality components and global linking problems.Methods and Results
We developed a device registry framework involving the following steps: (1) Data standards definition and representation of the research workflow, (2) Development of electronic case report forms using REDCap (Research Electronic Data Capture), (3) Data collection according to the clinical research workflow and, (4) Data augmentation by enriching the registry database with local electronic health records, governmental database and linked open data collections, (5) Data quality control and (6) Data dissemination through the registry Web site. Our registry adopted all applicable standardized data elements proposed by American College Cardiology / American Heart Association Clinical Data Standards, as well as variables derived from cardiac devices randomized trials and Clinical Data Interchange Standards Consortium. Local interoperability was performed between REDCap and data derived from Electronic Health Record system. The original data set was also augmented by incorporating the reimbursed values paid by the Brazilian government during a hospitalization for pacemaker implantation. By linking our registry to the open data collection repository Linked Clinical Trials (LinkedCT) we found 130 clinical trials which are potentially correlated with our pacemaker registry.Conclusion
This study demonstrates how standard and reproducible solutions can be applied in the implementation of medical registries to constitute a re-usable framework. Such approach has the potential to facilitate data integration between healthcare and research settings, also being a useful framework to be used in other biomedical registries. 相似文献76.
Toward a Low‐Cost Artificial Leaf: Driving Carbon‐Based and Bifunctional Catalyst Electrodes with Solution‐Processed Perovskite Photovoltaics 下载免费PDF全文
Tiva Sharifi Christian Larsen Jia Wang Wai Ling Kwong Eduardo Gracia‐Espino Guillaume Mercier Johannes Messinger Thomas Wågberg Ludvig Edman 《Liver Transplantation》2016,6(20)
Molecular hydrogen can be generated renewably by water splitting with an “artificial‐leaf device”, which essentially comprises two electrocatalyst electrodes immersed in water and powered by photovoltaics. Ideally, this device should operate efficiently and be fabricated with cost‐efficient means using earth‐abundant materials. Here, a lightweight electrocatalyst electrode, comprising large surface‐area NiCo2O4 nanorods that are firmly anchored onto a carbon–paper current collector via a dense network of nitrogen‐doped carbon nanotubes is presented. This electrocatalyst electrode is bifunctional in that it can efficiently operate as both anode and cathode in the same alkaline solution, as quantified by a delivered current density of 10 mA cm?2 at an overpotential of 400 mV for each of the oxygen and hydrogen evolution reactions. By driving two such identical electrodes with a solution‐processed thin‐film perovskite photovoltaic assembly, a wired artificial‐leaf device is obtained that features a Faradaic H2 evolution efficiency of 100%, and a solar‐to‐hydrogen conversion efficiency of 6.2%. A detailed cost analysis is presented, which implies that the material‐payback time of this device is of the order of 100 days. 相似文献
77.
Berta Lúcia Pereira Villagra Eduardo Pereira Cabral Gomes Robyn J. Burnham Sergio Romaniuc Neto 《Biodiversity and Conservation》2013,22(11):2505-2517
Climbing plant community composition and abundance was compared between the Alto da Serra de Paranapiacaba Biological Reserve (ASPRB) and the Nascentes de Paranapiacaba Municipal Natural Park (NPMNP), two protected areas in the largest Atlantic Forest remnant, southeastern Brazil. Climbing plants ≥1 cm in diameter were sampled in 52 quadrats of 10 × 20 m (1.04 ha). From these data we calculated the Shannon–Wiener diversity index, calculated abundance and importance values for families, performed a principal coordinate analysis, and created a similarity dendrogram (TWINSPAN). The composition and abundance of species between ASPRB and NPMNP differed significantly due to the successional state of the ASPRB forest, which was affected by more recent disturbance. There we found 34 species, while in the NPMNP, species richness was 72, with only 24 species in common. The two areas formed two groups corresponding to two distinct floristic subsets. These montane forests were characterized by a predominance of species of the Asteraceae. The high species richness, floristic composition, and community composition reflect the greater degree of conservation in the area of NPMNP. The high density and community composition of climbers in the more conserved area of rainforest may be due to the low intensity of disturbance. 相似文献
78.
Baudino L Shinohara Y Nimmerjahn F Furukawa J Nakata M Martínez-Soria E Petry F Ravetch JV Nishimura S Izui S 《Journal of immunology (Baltimore, Md. : 1950)》2008,181(9):6664-6669
Replacement of aspartic acid by alanine at position 265 (D265A) in mouse IgG1 results in a complete loss of interaction between this isotype and low-affinity IgG Fc receptors (Fc gammaRIIB and Fc gammaRIII). However, it has not yet been defined whether the D265A substitution could exhibit similar effects on the interaction with two other Fc gammaR (Fc gammaRI and Fc gammaRIV) and on the activation of complement. To address this question, 34-3C anti-RBC IgG2a and IgG2b switch variants bearing the D265A mutation were generated, and their effector functions and in vivo pathogenicity were compared with those of the respective wild-type Abs. The introduction of the D265A mutation almost completely abolished the binding of 34-3C IgG2a and IgG2b to all four classes of Fc gammaR and the activation of complement. Consequently, these mutants were hardly pathogenic. Although oligosaccharide side chains of these mutants were found to contain higher levels of sialic acids than those of wild-type Abs, the analysis of enzymatically desialylated D265A variants ruled out the possibility that very poor Fc-associated effector functions of the D265A mutants were due to an increased level of the mutant Fc sialylation. Thus, our results demonstrate that aspartic acid at position 265 is a residue critically implicated in triggering the Fc-associated effector functions of IgG, probably by defining a crucial three-dimensional structure of the Fc region. 相似文献
79.
Carlos Eduardo Cardoso Fedeli Juliana Sekeres Mussalem Luciana Girotto Gentil Simone Katz 《Experimental parasitology》2010,124(2):153-158
A 500 bp fragment encoding an isoform of cysteine proteinase from Leishmania (Leishmania) amazonensis was subcloned and expressed in the pHis vector, resulting in a recombinant protein of 24 kDa, rLacys24. In Western blots of L. (L.) amazonensis extracts, antibodies directed to rLacys24 recognized a cysteine proteinase isoform of 30 kDa. Analysis by fluorescence-activated cell sorter showed a significantly higher expression of CD8+ lymphocytes in animals immunized with rLacys24 plus CFA, whereas a low expression of CD4+ lymphocytes was observed in these animals. The cytotoxicity of lymphocytes isolated from mice immunized with rLacys24 plus CFA on L. (L.) amazonensis-infected macrophages was significantly higher than that observed in the presence of lymphocytes from control animals. Immunization of BALB/c mice with rLacys24 plus CFA resulted in a low but significant decrease of foot lesions after challenge with L. (L.) amazonensis compared to those exhibited by control mice. 相似文献
80.
Karen Valverde-Méndez Eduardo J. Hernández Dennis Matamoros Natalia Barboza 《The Annals of applied biology》2023,183(3):231-243
Begomoviruses (Geminiviridae family) are characterized by their high recombination rate and a wide range of hosts, making their control difficult. In Costa Rica, various species of bipartite begomoviruses have been reported, which are Pepper golden mosaic virus (PepGMV), Tomato yellow mottle virus (ToYMoV), Tomato leaf curl Sinaloa virus (ToLCSiV) and the monopartite begomovirus Tomato yellow leaf curl virus (TYLCV). Since the TYLCV first report in Costa Rica, neither additional knowledge has been produced on how this begomovirus has spread in the country's territory nor on the distribution of the other bipartite species. A total of 429 tomato samples collected during the years 2015–2016 were used to study these aspects. Each sample was georeferenced and analysed with various techniques such as nucleic acid hybridization, polymerase chain reaction (PCR) and sequencing for the begomoviruses previously reported in Costa Rica. It was found that the presence/absence of the different species can vary, depending on the province. TYLCV is present in the six provinces analysed in this work, with a proportion from 3.7 to 86.6 per cent. Alajuela, Cartago, and Heredia are the provinces most affected by tomato-infecting begomoviruses. Fourteen different haplotypes of TYLCV were detected, but all were identified as TYLCV-IL. The distribution of TYLCV was related to the presence of the whitefly Bemisia tabaci MED, especially in the country's main tomato production areas. This information allows the phytosanitary surveillance services to develop strategies for the integrated management of the disease and to contribute data to the genetic improvement programmes of the crop. 相似文献