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11.
The creationist movements in Brazil, although considered weak, are on the increase. The Brazilian legislation neither imposes any objection in teaching evolution nor obliges the teaching of creationism as an alternative to evolution in science classes. Furthermore, it allows the optional teaching of religion at schools. The aim of the present study was to evaluate the knowledge regarding biological evolution in freshman students from a Brazilian university. Such knowledge was related to sociocultural factors such as their parental education level, the type of high school the student graduated from (private or public school), their philosophical/religious position as well as the acceptance of creationism as an alternative to evolution. Among those factors, the latter two showed significant differences, in which the higher averages belonged both to the atheistic students and to those who do not accept creationism as an alternative to evolution. 相似文献
12.
Carlos Fernández-Palomeque Andres Grau Joan Perelló Pilar Sanchis Bernat Isern Rafel M. Prieto Antonia Costa-Bauzá Onofre J. Caldés Oriol Bonnin Ana Garcia-Raja Armando Bethencourt Felix Grases 《PloS one》2015,10(8)
Pathological calcification generally consists of the formation of solid deposits of hydroxyapatite (calcium phosphate) in soft tissues. Supersaturation is the thermodynamic driving force for crystallization, so it is believed that higher blood levels of calcium and phosphate increase the risk of cardiovascular calcification. However several factors can promote or inhibit the natural process of pathological calcification. This cross-sectional study evaluated the relationship between physiological levels of urinary phytate and heart valve calcification in a population of elderly out subjects. A population of 188 elderly subjects (mean age: 68 years) was studied. Valve calcification was measured by echocardiography. Phytate determination was performed from a urine sample and data on blood chemistry, end-systolic volume, concomitant diseases, cardiovascular risk factors, medication usage and food were obtained. The study population was classified in three tertiles according to level of urinary phytate: low (<0.610 μM), intermediate (0.61–1.21 μM), and high (>1.21 μM). Subjects with higher levels of urinary phytate had less mitral annulus calcification and were less likely to have diabetes and hypercholesterolemia. In the multivariate analysis, age, serum phosphorous, leukocytes total count and urinary phytate excretion appeared as independent factors predictive of presence of mitral annulus calcification. There was an inverse correlation between urinary phytate content and mitral annulus calcification in our population of elderly out subjects. These results suggest that consumption of phytate-rich foods may help to prevent cardiovascular calcification evolution. 相似文献
13.
Several bacterial pathogens have evolved the means to escape immune detection by mimicking host cell surface carbohydrates that are crucial for self/non-self recognition. Sialic acid, a terminal residue on these carbohydrates, inhibits activation of the alternate pathway of complement by recruiting the immune modulating molecule factors H, I, and iC3b. Sialylation of capsular polysaccharide (CPS) is important for virulence of group B streptococci (GBS), a significant human pathogen. We previously reported that cpsK, a gene within the cps locus of type III GBS, could complement a sialyltransferase deficient lst mutant of Haemophilus ducreyi, implicating its role in sialylation of the GBS capsule. To explore the function of cpsK in GBS capsule production, we created a mutant in cpsK. Immunoblot analysis and enzyme-linked immunosorbent assay using anti-type III CPS antisera demonstrated that the mutant CPS did not contain sialic acid. This was confirmed by high-performance liquid chromatography after mild acid hydrolysis of the CPS. Although increased CPS chain length was seen for this strain, CPS production was <20% of the parental isolate. An episomal cpsK copy restored synthesis of sialo-CPS to wild-type levels. These data support our hypothesis that cpsK encodes the GBS CPS sialyltransferase and provide further evidence that lack of CPS oligosaccharide sialylation reduces the amount of CPS expressed on the cell surface. These observations also imply that one or more of the components involved in synthesis or transport of oligosaccharide repeating units requires a sialo-oligosaccharide for complete activity. 相似文献
14.
Ganzella M Moreira JD Almeida RF Böhmer AE Saute JA Holmseth S Souza DO 《Purinergic signalling》2012,8(1):49-58
Overstimulation of the glutamatergic system (excitotoxicity) is involved in various acute and chronic brain diseases. Several
studies support the hypothesis that guanosine-5′-monophosphate (GMP) can modulate glutamatergic neurotransmission. The aim
of this study was to evaluate the effects of chronically administered GMP on brain cortical glutamatergic parameters in mice.
Additionally, we investigated the neuroprotective potential of the GMP treatment submitting cortical brain slices to oxygen
and glucose deprivation (OGD). Moreover, measurements of the cerebrospinal fluid (CSF) purine levels were performed after
the treatment. Mice received an oral administration of saline or GMP during 3 weeks. GMP significantly decreases the cortical
brain glutamate binding and uptake. Accordingly, GMP reduced the immunocontent of the glutamate receptors subunits, NR2A/B
and GluR1 (NMDA and AMPA receptors, respectively) and glutamate transporters EAAC1 and GLT1. GMP treatment significantly reduced
the immunocontent of PSD-95 while did not affect the content of Snap 25, GLAST and GFAP. Moreover, GMP treatment increased
the resistance of neocortex to OGD insult. The chronic GMP administration increased the CSF levels of GMP and its metabolites.
Altogether, these findings suggest a potential modulatory role of GMP on neocortex glutamatergic system by promoting functional
and plastic changes associated to more resistance of mice neocortex against an in vitro excitotoxicity event. 相似文献
15.
Renata Lanoni Eneiva Carla Carvalho Celeghini Valdemar De Giuli Júnior Carla Patricia Teodoro de Carvalho Gabriela Bertaiolli Zoca Laura Nataly Garcia-Oliveros Leonardo Batissaco Letícia Zoccolaro Oliveira Rubens Paes de Arruda 《Animal Reproduction》2021,18(1)
Coenzyme Q-10 (CoQ-10) is a cofactor for mitochondrial electron transport chain and may be an alternative to improve sperm quality of cryopreserved equine semen. This work aimed to improve stallion semen quality after freezing by adding CoQ-10 to the cryopreservation protocol. Seven saddle stallions were utilized. Each animal was submitted to five semen collections and freezing procedures. For cryopreservation, each ejaculate was divided in three treatments: 1) Botucrio® diluent (control); 2) 50 μmol CoQ-10 added to Botucrio® diluent; 3) 1 mmol CoQ-10 added to Botucrio® diluent. Semen batches were analyzed for sperm motility characteristics (CASA), plasma and acrosomal membranes integrity and mitochondrial membrane potential (by fluorescence probes propidium iodide, Hoechst 33342, FITC-PSA and JC-1, respectively), alterations in cytoskeletal actin (phalloidin-FITC) and mitochondrial function (diaminobenzidine; DAB). The 1 mmol CoQ-10 treatment presented higher (P<0.05) amount (66.8%) of sperm cells with fully stained midpiece (indicating high mitochondrial activity) and higher (P<0.05) amount (81.6%) of cells without actin reorganization to the post-acrosomal region compared to control group (60.8% and 76.0%, respectively). It was concluded that the addition of 1 mmol CoQ-10 to the freezing diluent was more effective in preserving mitochondria functionality and cytoskeleton of sperm cells submitted to cryopreservation process. 相似文献
16.
Clévio Nóbrega Isabel Nascimento-Ferreira Isabel Onofre David Albuquerque Hirokazu Hirai Nicole Déglon Luís Pereira de Almeida 《PloS one》2013,8(1)
Machado-Joseph disease (MJD) or spinocerebellar ataxia type 3 (SCA3) is an autosomal dominantly-inherited neurodegenerative disorder caused by the over-repetition of a CAG codon in the MJD1 gene. This expansion translates into a polyglutamine tract that confers a toxic gain-of-function to the mutant protein – ataxin-3, leading to neurodegeneration in specific brain regions, with particular severity in the cerebellum. No treatment able to modify the disease progression is available. However, gene silencing by RNA interference has shown promising results. Therefore, in this study we investigated whether lentiviral-mediated allele-specific silencing of the mutant ataxin-3 gene, after disease onset, would rescue the motor behavior deficits and neuropathological features in a severely impaired transgenic mouse model of MJD. For this purpose, we injected lentiviral vectors encoding allele-specific silencing-sequences (shAtx3) into the cerebellum of diseased transgenic mice expressing the targeted C-variant of mutant ataxin-3 present in 70% of MJD patients. This variation permits to discriminate between the wild-type and mutant forms, maintaining the normal function of the wild-type allele and silencing only the mutant form. Quantitative analysis of rotarod performance, footprint and activity patterns revealed significant and robust alleviation of gait, balance (average 3-fold increase of rotarod test time), locomotor and exploratory activity impairments in shAtx3-injected mice, as compared to control ones injected with shGFP. An important improvement of neuropathology was also observed, regarding the number of intranuclear inclusions, calbindin and DARPP-32 immunoreactivity, fluorojade B and Golgi staining and molecular and granular layers thickness. These data demonstrate for the first time the efficacy of gene silencing in blocking the MJD-associated motor-behavior and neuropathological abnormalities after the onset of the disease, supporting the use of this strategy for therapy of MJD. 相似文献
17.
Group B streptococci (GBS) remain the most significant bacterial pathogen causing neonatal sepsis, pneumonia and meningitis in the USA despite CDC-recommended chemoprophylaxis strategies for preventing infection. To cause infection pathogens such as GBS must evade recognition and clearance by the host's immune system. Strategies for avoidance of opsonization and phagocytic killing include elaboration of antiopsonophagocytic capsules and surface proteins. During screening for mutants of GBS that were attenuated for virulence in a neonatal rat sepsis model, we identified a mutant with a transposon insertion in the ponA gene. ponA encodes an extra-cytoplasmic penicillin-binding protein PBP1a, a newly identified virulence trait for GBS that promotes resistance to phagocytic killing independent of capsular polysaccharide. Complementation analysis in vivo and in vitro confirmed that the altered phenotypes observed in the mutant were due to the transposon insertion in ponA. Deletion of PBP1a does not affect C3 deposition on GBS suggesting that mechanism by which PBP1a protects GBS from phagocytic killing is distinct from the antiopsonic activity of capsular polysaccharide. This is the first report describing expression of an antiphagocytic surface protein by GBS and represents a novel mechanism for evasion of immune recognition and clearance that may explain the decreased virulence observed in Gram-positive bacterial species for penicillin-binding protein mutants. 相似文献
18.
Marina T. Durand Christiane Becari Mauro de Oliveira Jussara M. do Carmo Carlos Alberto Aguiar Silva Cibele M. Prado Rubens Fazan Jr Helio C. Salgado 《PloS one》2014,9(8)
The effect of pyridostigmine (PYR) - an acetylcholinesterase inhibitor - on hemodynamics and cardiac autonomic control, was never studied in conscious myocardial infarcted mice. Telemetry transmitters were implanted into the carotid artery under isoflurane anesthesia. Seven to ten days after recovery from the surgery, basal arterial pressure and heart rate were recorded, while parasympathetic and sympathetic tone (ΔHR) was evaluated by means of methyl atropine and propranolol. After the basal hemodynamic recording the mice were subjected to left coronary artery ligation for producing myocardial infarction (MI), or sham operation, and implantation of minipumps filled with PYR or saline. Separate groups of anesthetized (isoflurane) mice previously (4 weeks) subjected to MI, or sham coronary artery ligation, were submitted to cardiac function examination. The mice exhibited an infarct length of approximately 12%, no change in arterial pressure and increased heart rate only in the 1st week after MI. Vagal tone decreased in the 1st week, while the sympathetic tone was increased in the 1st and 4th week after MI. PYR prevented the increase in heart rate but did not affect the arterial pressure. Moreover, PYR prevented the increase in sympathetic tone throughout the 4 weeks. Concerning the parasympathetic tone, PYR not only impaired its attenuation in the 1st week, but enhanced it in the 4th week. MI decreased ejection fraction and increased diastolic and systolic volume. Therefore, the pharmacological increase of peripheral acetylcholine availability by means of PYR prevented tachycardia, increased parasympathetic and decreased sympathetic tone after MI in mice. 相似文献
19.
Mariana de Andrade Wagner Benoît Francis Patrice Loeuille Carolina Moriani Siniscalchi Gladys Flávia Melo-de-Pinna José Rubens Pirani 《Plant Systematics and Evolution》2014,300(5):1219-1233
Vernonieae is one of the major tribes in Asteraceae (subfamily Cichorioideae) with ca. 1,100 species placed into 129 genera. Currently, 21 subtribes are recognized in Vernonieae and one of them is Lychnophorinae, almost entirely endemic to Brazil, containing 11 genera and ca. 100 species. About 42 % of Lychnophorinae genera are monophyletic, reflecting the poorly understood relationships among the members of the group. Trichomes are one of the most useful anatomical characters to be used in angiosperm taxonomy; they are diverse, exist in many taxa and are not difficult to study. This work intends to illustrate non-glandular leaf trichome diversity in Lychnophorinae and discuss this diversity in the light of the subtribe’s taxonomy. Sampled material included 67 species of 11 genera. Macerations and free hand sections were performed to be analyzed in the light microscope and photographed. A phenogram was generated using a matrix with 67 terminals (species) and 18 characters coded as binary. The subtribe Lychnophorinae displays a great diversity of non-glandular trichomes (5 types and 18 subtypes). The present study reveals the great diversity of non-glandular trichomes in Lychnophorinae. While trichome complement is of little use to distinguish genera, it appears to be a valuable characteristic at a lower taxonomic level to identify closely morphologically related species. 相似文献
20.
Incubation of rat-liver microsomes, previously azide-treated to inhibit catalase, with H2O2 caused a loss of cytochrome P-450 but not of cytochrome b5. This loss of P-450 was not prevented by scavengers of hydroxyl radical, chain-breaking antioxidants or metal ion-chelating agents. Application of the thiobarbituric acid (TBA) assay to the reaction mixture suggested that H2O2 induces lipid peroxidation, but this was found to be due largely or completely to an effect of H2O2 on the TBA assay. By contrast, addition of ascorbic acid and Fe(III) to the microsomes led to lipid peroxidation and P-450 degradation: both processes were inhibited by chelating agents and chain-breaking antioxidants, but not by hydroxyl radical scavengers. H2O2 inhibited ascorbate/Fe (III)-induced microsomal lipid peroxidation, but part of this effect was due to an action of H2O2 in the TBA test itself. H2O2 also decreased the colour measured after carrying out the TBA test upon authentic malondialdehyde, tetraethoxypropane, a DNA-Cu2+/o-phenanthroline system in the presence of a reducing agent, ox-brain phospholipid liposomes in the presence of Fe(III) and ascorbate, or a bleomycin-iron ion/DNA/ascorbate system. Caution must be used in interpreting the results of TBA tests upon systems containing H2O2. 相似文献