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11.
A new genus and species of troglobitic buthid scorpion are described on the basis of a single specimen collected in Brazil. This is the first cavernicolous scorpion ever found in Brazil, and only the second to be found in South America. Some considerations on troglobitic scorpions are proposed. 相似文献
12.
Ivo H. J. Ploemen Miguel Prudêncio Bruno G. Douradinha Jai Ramesar Jannik Fonager Geert-Jan van Gemert Adrian J. F. Luty Cornelus C. Hermsen Robert W. Sauerwein Fernanda G. Baptista Maria M. Mota Andrew P. Waters Ivo Que Clemens W. G. M. Lowik Shahid M. Khan Chris J. Janse Blandine M. D. Franke-Fayard 《PloS one》2009,4(11)
The quantitative analysis of Plasmodium development in the liver in laboratory animals in cultured cells is hampered by low parasite infection rates and the complicated methods required to monitor intracellular development. As a consequence, this important phase of the parasite''s life cycle has been poorly studied compared to blood stages, for example in screening anti-malarial drugs. Here we report the use of a transgenic P. berghei parasite, PbGFP-Luccon, expressing the bioluminescent reporter protein luciferase to visualize and quantify parasite development in liver cells both in culture and in live mice using real-time luminescence imaging. The reporter-parasite based quantification in cultured hepatocytes by real-time imaging or using a microplate reader correlates very well with established quantitative RT-PCR methods. For the first time the liver stage of Plasmodium is visualized in whole bodies of live mice and we were able to discriminate as few as 1–5 infected hepatocytes per liver in mice using 2D-imaging and to identify individual infected hepatocytes by 3D-imaging. The analysis of liver infections by whole body imaging shows a good correlation with quantitative RT-PCR analysis of extracted livers. The luminescence-based analysis of the effects of various drugs on in vitro hepatocyte infection shows that this method can effectively be used for in vitro screening of compounds targeting Plasmodium liver stages. Furthermore, by analysing the effect of primaquine and tafenoquine in vivo we demonstrate the applicability of real time imaging to assess parasite drug sensitivity in the liver. The simplicity and speed of quantitative analysis of liver-stage development by real-time imaging compared to the PCR methodologies, as well as the possibility to analyse liver development in live mice without surgery, opens up new possibilities for research on Plasmodium liver infections and for validating the effect of drugs and vaccines on the liver stage of Plasmodium. 相似文献
13.
Kelli Cristina Micocci Ana Carolina Baptista Moreno Martin Cyntia de Freitas Montenegro Araceli Cristina Durante Normand Pouliot Márcia Regina Cominetti Heloisa Sobreiro Selistre-de-Araujo 《Biochimie》2013
ADAM9 (A Disintegrin And Metalloproteinase 9) is a member of the ADAM protein family which contains a disintegrin domain. This protein family plays key roles in many physiological processes, including fertilization, migration, and cell survival. The ADAM proteins have also been implicated in various diseases, including cancer. Specifically, ADAM9 has been suggested to be involved in metastasis. To address this question, we generated ADAM9 knockdown clones of MDA-MB-231 breast tumor cells using silencing RNAs that were tested for cell adhesion, proliferation, migration and invasion assays. In RNAi-mediated ADAM9 silenced MDA-MB-231 cells, the expression of ADAM9 was lower from the third to the sixth day after silencing and inhibited tumor cell invasion in matrigel by approximately 72% when compared to control cells, without affecting cell adhesion, proliferation or migration. In conclusion, the generation of MDA-MB-231 knockdown clones lacking ADAM9 expression inhibited tumor cell invasion in vitro, suggesting that ADAM9 is an important molecule in the processes of invasion and metastasis. 相似文献
14.
Igor L. Baptista Willian J. Silva Guilherme G. Artioli Joao Paulo L. F. Guilherme Marcelo L. Leal Marcelo S. Aoki Elen H. Miyabara Anselmo S. Moriscot 《PloS one》2013,8(10)
In the present study we have compared the effects of leucine supplementation and its metabolite β-hydroxy-β-methyl butyrate (HMB) on the ubiquitin-proteasome system and the PI3K/Akt pathway during two distinct atrophic conditions, hindlimb immobilization and dexamethasone treatment. Leucine supplementation was able to minimize the reduction in rat soleus mass driven by immobilization. On the other hand, leucine supplementation was unable to provide protection against soleus mass loss in dexamethasone treated rats. Interestingly, HMB supplementation was unable to provide protection against mass loss in all treatments. While solely fiber type I cross sectional area (CSA) was protected in immobilized soleus of leucine-supplemented rats, none of the fiber types were protected by leucine supplementation in rats under dexamethasone treatment. In addition and in line with muscle mass results, HMB treatment did not attenuate CSA decrease in all fiber types against either immobilization or dexamethasone treatment. While leucine supplementation was able to minimize increased expression of both Mafbx/Atrogin and MuRF1 in immobilized rats, leucine was only able to minimize Mafbx/Atrogin in dexamethasone treated rats. In contrast, HMB was unable to restrain the increase in those atrogenes in immobilized rats, but in dexamethasone treated rats, HMB minimized increased expression of Mafbx/Atrogin. The amount of ubiquitinated proteins, as expected, was increased in immobilized and dexamethasone treated rats and only leucine was able to block this increase in immobilized rats but not in dexamethasone treated rats. Leucine supplementation maintained soleus tetanic peak force in immobilized rats at normal level. On the other hand, HMB treatment failed to maintain tetanic peak force regardless of treatment. The present data suggested that the anti-atrophic effects of leucine are not mediated by its metabolite HMB. 相似文献
15.
Ana L. Santos Vanessa Oliveira Inês Baptista Isabel Henriques Newton C. M. Gomes Adelaide Almeida António Correia Ângela Cunha 《Archives of microbiology》2013,195(1):63-74
The biological effects of UV radiation of different wavelengths (UVA, UVB and UVC) were assessed in nine bacterial isolates displaying different UV sensitivities. Biological effects (survival and activity) and molecular markers of oxidative stress [DNA strand breakage (DSB), generation of reactive oxygen species (ROS), oxidative damage to proteins and lipids, and the activity of antioxidant enzymes catalase and superoxide dismutase] were quantified and statistically analyzed in order to identify the major determinants of cell inactivation under the different spectral regions. Survival and activity followed a clear wavelength dependence, being highest under UVA and lowest under UVC. The generation of ROS, as well as protein and lipid oxidation, followed the same pattern. DNA damage (DSB) showed the inverse trend. Multiple stepwise regression analysis revealed that survival under UVA, UVB and UVC wavelengths was best explained by DSB, oxidative damage to lipids, and intracellular ROS levels, respectively. 相似文献
16.
The additive genetic effects of traits can be used to predict evolutionary trajectories,
such as responses to selection. Non-additive genetic and maternal environmental effects
can also change evolutionary trajectories and influence phenotypes, but these effects have
received less attention by researchers. We partitioned the phenotypic variance of survival
and fitness-related traits into additive genetic, non-additive genetic and maternal
environmental effects using a full-factorial breeding design within two allopatric
populations of Atlantic salmon (Salmo salar). Maternal environmental effects were
large at early life stages, but decreased during development, with non-additive genetic
effects being most significant at later juvenile stages (alevin and fry). Non-additive
genetic effects were also, on average, larger than additive genetic effects. The
populations, generally, did not differ in the trait values or inferred genetic
architecture of the traits. Any differences between the populations for trait values could
be explained by maternal environmental effects. We discuss whether the similarities in
architectures of these populations is the result of natural selection across a common
juvenile environment. 相似文献
17.
Clavulanic acid (CA), a potent β-lactamase inhibitor, is produced by a filamentous bacterium. Here, the effect of DO and shear,
expressed as impeller tip velocity, on CA production was examined. Cultivations were performed in a 4 L fermentor with speeds
of 600, 800 and 1,000 rpm and a fixed air flow rate (0.5 vvm). Also, cultivation with automatic control of dissolved oxygen,
at 50% air saturation, by varying stirrer speed and using a mixture of air and O2 (10% v/v) in the inlet gas, and a cultivation with fixed stirrer speed of 800 rpm and air flow rate of 0.5 vvm, enriched
with 10% v/v O2, were performed. Significant variations in CA titer, CA production rate and O2 uptake-rate were observed. It was also found that the DO level has no remarkable effect on CA production once a critical
level is surpassed. The most significant improvement in CA production was related to high stirrer speeds. 相似文献
18.
R Gon?alves LA Szmuchrowski LS Prado BP Couto JCQ Machado VO Damasceno JA Lamounier 《Biology of sport / Institute of Sport》2015,32(3):255-260
The aim of this study was to assess the suitability of body mass index, waist circumference, waist-to-height ratio and aerobic fitness as predictors of cardiovascular risk factor clustering in children. A cross-sectional study was conducted with 290 school boys and girls from 6 to 10 years old, randomly selected. Blood was collected after a 12-hour fasting period. Blood pressure, waist circumference (WC), height and weight were evaluated according to international standards. Aerobic fitness (AF) was assessed by the 20-metre shuttle-run test. Clustering was considered when three of these factors were present: high systolic or diastolic blood pressure, high low-density lipoprotein (LDL) cholesterol, high triglycerides, high plasma glucose, high insulin concentrations and low high-density lipoprotein (HDL) cholesterol. A ROC curve identified the cut-off points of body mass index (BMI), WC, waist-to-height ratio (WHtR) and AF as predictors of risk factor clustering. BMI, WC and WHR resulted in significant areas under the ROC curves, which was not observed for AF. The anthropometric variables were good predictors of cardiovascular risk factor clustering in both sexes, whereas aerobic fitness should not be used to identify cardiovascular risk factor clustering in these children. 相似文献
19.
Narayana PB Fazolini André LS Cruz Miriam BF Werneck Jo?o PB Viola Clarissa M Maya-Monteiro Patrícia T Bozza 《Cell cycle (Georgetown, Tex.)》2015,14(16):2667-2676
Accumulating evidence suggests that obesity and enhanced inflammatory reactions are predisposing conditions for developing colon cancer. Obesity is associated with high levels of circulating leptin. Leptin is an adipocytokine that is secreted by adipose tissue and modulates immune response and inflammation. Lipid droplets (LD) are organelles involved in lipid metabolism and production of inflammatory mediators, and increased numbers of LD were observed in human colon cancer. Leptin induces the formation of LD in macrophages in a PI3K/mTOR pathway-dependent manner. Moreover, the mTOR is a serine/threonine kinase that plays a key role in cellular growth and is frequently altered in tumors. We therefore investigated the role of leptin in the modulation of mTOR pathway and regulation of lipid metabolism and inflammatory phenotype in intestinal epithelial cells (IEC-6 cells). We show that leptin promotes a dose- and time-dependent enhancement of LD formation. The biogenesis of LD was accompanied by enhanced CXCL1/CINC-1, CCL2/MCP-1 and TGF-β production and increased COX-2 expression in these cells. We demonstrated that leptin-induced increased phosphorylation of STAT3 and AKT and a dose and time-dependent mTORC activation with enhanced phosphorilation of the downstream protein P70S6K protein. Pre-treatment with rapamycin significantly inhibited leptin effects in LD formation, COX-2 and TGF-β production in IEC-6 cells. Moreover, leptin was able to stimulate the proliferation of epithelial cells on a mTOR-dependent manner. We conclude that leptin regulates lipid metabolism, cytokine production and proliferation of intestinal cells through a mechanism largely dependent on activation of the mTOR pathway, thus suggesting that leptin-induced mTOR activation may contribute to the obesity-related enhanced susceptibility to colon carcinoma. 相似文献
20.
K Zinner R Casadei de Baptista G Cilento 《Biochemical and biophysical research communications》1974,61(3):889-898
Indole-3-pyruvic acid luminesces in aerated dimethyl-sulfoxide solutions in the presence of potassium tert-butoxide. The chemiluminescence spectrum indicates the occurrence of multiple bands whose relative intensities change with time. This behaviour is connected with the presence of two forms of indole-pyruvic acid and with two different reactions, namely at the side chain giving indole-3-carboxaldehyde and at the indole nucleus giving ultimately a product of the N-formyl-kynurenine type.The results suggest that indole-pyruvate is a potential luciferin. This inference is strengthened by the fact that it can originate “in vivo” both indole-aldehyde and oxalate.The reaction at the indole nucleus is tentatively considered a model for tryptophan dioxygenase and related systems. 相似文献