Institute of Biosciences


Institute of Biosciences

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Ganchev T.D.,Federal University of Mato Grosso | Ganchev T.D.,Varna Technical University | Jahn O.,Federal University of Mato Grosso | Jahn O.,Zoological Research Museum A Koenig Zfmk | And 6 more authors.
Expert Systems with Applications | Year: 2015

Traditional human-observer-based biological surveys are expensive. Therefore most biodiversity studies are implemented only periodically, for short periods, and predominantly during daytime and under favorable weather conditions. Automated data acquisition and analysis can overcome these shortcomings and facilitate continuous monitoring. Here we report on the development of an automated acoustic recognizer for Southern Lapwing Vanellus chilensis lampronotus vocalizations, a first for this species. The recognizer is a species-specific information retrieval agent, which searches throughout long audio recordings in order to detect and timestamp call events of the target species. The recognizer relies on a log-likelihood ratio estimator, based on a Gaussian Mixture Model-Universal Background Model (GMM-UBM), complemented with purposely-developed temporal post-processing that incorporates domain knowledge about the structure of V. chilensis vocalizations. Validation experiments with real-field recordings of complex soundscapes indicate that the recognizer is sensitive enough to register V. chilensis call events with sound levels down to -30 dB and recognition accuracy of up to 85.6%, at zero false positive rates. The recognizer is considered a valuable tool for computer-assisted analysis of hourly and daily acoustic activity of V. chilensis over extended periods of time, as it offers an indispensable support to long-term monitoring studies and conservation efforts in the Pantanal region.1 © 2015 Elsevier Ltd.

News Article | November 30, 2016

HOUSTON - (Nov. 30, 2016) - A drug used now to treat Type 2 diabetes may someday help beat breast and ovarian cancers, but not until researchers decode the complex interactions that in some cases help promote tumors, according to Rice University scientists. Rice bioscientist Daniel Carson and alumna Micaela Morgado researched thiazolidinediones, small molecules used to fight diabetes, that can halt the expression of glycoproteins that make up the protective mucus that lines cells and organs in the body. These mucus cells are manipulated by tumors to keep them safe from chemotherapy and the immune system. But there are problems to be solved before the drug can be used to fight cancer, Carson said, including the fact that small doses appropriate for diabetes treatment actually increase cancer risk for patients with diabetes. The drug they studied, rosiglitazone, shows promise only if it can be delivered in large-enough doses and directly to tumors, he said. The work will appear in the January issue of the Journal of Cellular Biochemistry. "My lab is interested in the class of very high-molecular-weight glycoproteins that absorb water and cover and protect the surfaces of your cells," Carson said. "These mucins perform a very important protective function, lining your mouth, your glandular structures and your gastrointestinal tract, essentially acting like Teflon for those surfaces. "But tumors have learned a trick," he said. "Instead of keeping mucins on one end of a cell, where they would normally protect it from the external environment, they start putting mucins all over their surfaces. Cells of the immune system that kill tumors have to make contact with the cancer cell's surface, but when they have these big barrier molecules on the surface, they're protected. "If we can intervene in patients and reduce mucin levels, maybe the host immune system can do its job and kill the tumors," Carson said. The lab studied the effects of one thiazolidinedione, rosiglitazone, on a glycoprotein known as MUC16 that protects breast and ovarian cancer cells. Another, pioglitazone, was the focus of a recent Rice breast cancer study, and Carson's lab previously studied the effects of rosiglitazone on another glycoprotein, MUC1. "MUC16 wound up being particularly interesting because it's also known as CA125, which is the gold standard marker for ovarian cancer," he said. "Women are routinely monitored for CA125 levels that normally are found at very low levels in serum. If you have certain tumors, these cancer cells begin to release fragments of CA125." Carson said doses of rosiglitazone fed to cancer cell lines in the lab shut down the production of glycoproteins by interfering with the actions of cytokines that trigger the cells' protective response and elevate MUC16 production. "It turns out the tumor microenvironment is rich in these cytokines," he said. "You would think these pro-inflammatory mediators would be a good thing because they enhance the immune response to the tumor. But, in fact, they also enhance the tumor's protective response." He said stopping production of MUC16 for even a couple of days might be enough to breach the protective shield and allow immune cells to begin the destruction of a tumor. "If you could shut down synthesis by 90 percent or more, which is achievable with these drugs, within two days you have enough reduction to remove the tumor's protective coating. "There's nothing here we can take to a clinic yet," Carson said. "We learned about ways to intervene and reduce the expression, but we either need better drugs that can do it at much lower, pharmacologically achievable levels, or we need to have a way to target drugs so we can get tumor-specific, superphysiological concentrations that would achieve the goal. "The upside is that these drugs are already FDA approved," he said. "If we can repurpose them, we don't have to go through the same duration of regulatory process required to use them for cancer therapy." Morgado is now a postdoctoral researcher at Yale University Medical School. Carson is the Schlumberger Chair of Advanced Studies and Research and a professor of biosciences at Rice. The Rice University Fellowship Fund and Rice University Institute of Biosciences and Bioengineering Medical Innovation Fund supported the research. This news release can be found online at http://news. An image of endometrial cancer tissues shows cell nuclei (blue), an epithelial marker protein called E-cadherin (green) and MUC16 glycoproteins (red) that are suspected of protecting tumors. Rice University researchers discovered that a drug used now to treat Type 2 diabetes might help battle breast and ovarian cancers by manipulating the interactions that overexpress the protective mucus that tumors use to defend against chemotherapy and the body's immune system. (Credit: Carson Lab/Rice University) Located on a 300-acre forested campus in Houston, Rice University is consistently ranked among the nation's top 20 universities by U.S. News & World Report. Rice has highly respected schools of Architecture, Business, Continuing Studies, Engineering, Humanities, Music, Natural Sciences and Social Sciences and is home to the Baker Institute for Public Policy. With 3,910 undergraduates and 2,809 graduate students, Rice's undergraduate student-to-faculty ratio is 6-to-1. Its residential college system builds close-knit communities and lifelong friendships, just one reason why Rice is ranked No. 1 for happiest students and for lots of race/class interaction by the Princeton Review. Rice is also rated as a best value among private universities by Kiplinger's Personal Finance. To read "What they're saying about Rice," go to http://tinyurl. .

PubMed | Member of the Exercise Metabolism and Nutrition Center tri, West Parana State University, Federal University of Uberlandia, São Paulo State University and 2 more.
Type: Journal Article | Journal: Diabetology & metabolic syndrome | Year: 2016

The metabolic syndrome (MS) has been assessed since childhood mainly because of the nutritional and epidemiological transition that has occurred worldwide. Our objectives were to explore the MS and its components according to anthropometric and demographic factors and to assess the relationship among MS components and dietary characteristics in overweight and obese schoolchildren.This was a cross-sectional study which included 147 schoolchildren (aged 6-10 years) from three elementary schools, with body mass index (BMI) higher than the 85th percentile. Sexual maturation stages, anthropometric measures (weight, height, skinfold thickness and waist circumference), biochemical data (glucose, HDL-C and triacylglycerol), blood pressure and dietary intake were assessed. The metabolic syndrome was diagnosed if three or more of the following components were presented: waist circumference90th age and sex-specific cut-off, blood pressure90th age, sex and height-specific cut-off, glucose100mg/dL, HDL-C40mg/dL and triacylglycerols110mg/dL. The dietary intake was assessed by three non-consecutive 24-h recalls. The T test, Kruskal-Wallis and multiple linear regression analysis were applied to assess MS components and dietary intake.The MS percentage was 10.2% and it was higher in obese children and ones with high body fat percentage. The waist circumference was the main altered component of MS and 62% of overweight schoolchildren showed at least one altered component of MS. The components of metabolic syndrome associated with dietary intake were triacylglycerol (positive association with saturated and monounsaturated fat, whole-milk products and processed foods and negative associated with legumes and polyunsaturated fat), glycemia (positive association with processed foods and negative with cereals), HDL-C (positive association with vegetables and greens) and waist circumference was negative associated with protein.The frequency of MS was higher in obese than overweight schoolchildren and the frequency of at least one MS component was high in more than half of our subjects. The waist circumference was the most frequent among all other components. The triacylglycerol and glycemia were the most frequent MS components associated with dietary intake. Unprocessed food was considered a protective dietary factor for MS metabolic components and processed food with high percentage of sugar and saturated fat was a risk factor for MS metabolic components.

Tavares M.,University of Sao Paulo | Gouvea A.,Institute of Biosciences
Zootaxa | Year: 2013

A new species of deep-water brachyuran crab, Robertsella meridionalis, from Brazil is described and illustrated. The new species can be easily separated from its northwestern Atlantic counterpart, R. mystica Guinot, 1969, by a suite of carapace and appendage characters. Robertsella mystica is redescribed and illustrated. Putative sound-producing structures in the genus Robertsella are first described. Copyright © 2013 Magnolia Press.

Secco M.,Institute of Biosciences | Bueno Jr. C.,Institute of Biosciences | Vieira N.M.,Institute of Biosciences | Almeida C.,Institute of Biosciences | And 7 more authors.
Stem Cell Reviews and Reports | Year: 2013

The combination of cell therapy with growth factors could be a useful approach to treat progressive muscular dystrophies. Here, we demonstrate, for the first time, that IGF-1 considerably enhances the myogenesis of human umbilical cord (UC) mesenchymal stromal cells (MSCs) in vitro and that IGF-1 enhances interaction and restoration of dystrophin expression in co-cultures of MSCs and muscle cells from Duchenne patients. In vivo studies showed that human MSCs were able to reach the skeletal muscle of LAMA2dy/2j dystrophic mice, through systemic delivery, without immunosuppression. Moreover, we showed, for the first time, that IGF-1 injected systemically together with MSCs markedly reduced muscle inflammation and fibrosis, and significantly improved muscle strength in dystrophic mice. Our results suggest that a combined treatment with IGF-1 and MSCs enhances efficiency of muscle repair and, therefore, should be further considered as a potential therapeutic approach in muscular dystrophies. © 2012 Springer Science+Business Media, LLC.

Zatz M.,Institute of Biosciences | Vieira N.M.,Institute of Biosciences | Zucconi E.,Institute of Biosciences | Pelatti M.,Institute of Biosciences | And 8 more authors.
Neuromuscular Disorders | Year: 2015

Here we summarize the clinical history of Ringo, a golden retriever muscular dystrophy (GRMD) dog, who had a mild phenotype despite the absence of muscle dystrophin. Ringo died of cardiac arrest at age 11 and therefore displayed a normal lifespan. One of his descendants, Suflair, born April 2006, also displays a mild course. Dystrophin analysis confirmed total absence of muscle dystrophin in both dogs. Muscle utrophin expression did not differ from severely affected GRMD dogs. Finding what protects these special dogs from the dystrophic degeneration process is now a great challenge that may open new avenues for treatment. But most importantly, the demonstration that it is possible to have a functional muscle, in a medium-large animal even in the absence of dystrophin, brings new hope for Duchenne patients. © 2015 Elsevier B.V.

Home > Press > Rice expands graphene repertoire with MRI contrast agent: Metal-free fluorinated graphene shows no signs of toxicity in cell culture tests Abstract: Graphene, the atomically thin sheets of carbon that materials scientists are hoping to use for everything from nanoelectronics and aircraft de-icers to batteries and bone implants, may also find use as contrast agents for magnetic resonance imaging (MRI), according to new research from Rice University. "They have a lot of advantages compared with conventionally available contrast agents," Rice researcher Sruthi Radhakrishnan said of the graphene-based quantum dots she has studied for the past two years. "Virtually all of the widely used contrast agents contain toxic metals, but our material has no metal. It's just carbon, hydrogen, oxygen and fluorine, and in all of our tests so far it has shown no signs of toxicity." The initial findings for Rice's nanoparticles -- disks of graphene that are decorated with fluorine atoms and simply organic molecules that make them magnetic -- are described in a new paper in the journal Particle and Particle Systems Characterization. Pulickel Ajayan, the Rice materials scientist who is directing the work, said the fluorinated graphene oxide quantum dots could be particularly useful as MRI contrast agents because they could be targeted to specific kinds of tissues. "There are tried-and-true methods for attaching biomarkers to carbon nanoparticles, so one could easily envision using these quantum dots to develop tissue-specific contrast agents," Ajayan said. "For example, this method could be used to selectively target specific types of cancer or brain lesions caused by Alzheimer's disease. That kind of specificity isn't available with today's contrast agents." MRI scanners make images of the body's internal structures using strong magnetic fields and radio waves. As diagnostic tests, MRIs often provide greater detail than X-rays without the harmful radiation, and as a result, MRI usage has risen sharply over the past decade. More than 30 million MRIs are performed annually in the U.S. Radhakrishnan said her work began in 2014 after Ajayan's research team found that adding fluorine to either graphite or graphene caused the materials to show up well on MRI scans. All materials are influenced by magnetic fields, including animal tissues. In MRI scanners, a powerful magnetic field causes individual atoms throughout the body to become magnetically aligned. A pulse of radio energy is used to disrupt this alignment, and the machine measures how long it takes for the atoms in different parts of the body to become realigned. Based on these measures, the scanner can build up a detailed image of the body's internal structures. MRI contrast agents shorten the amount of time it takes for tissues to realign and significantly improve the resolution of MRI scans. Almost all commercially available contrast agents are made from toxic metals like gadolinium, iron or manganese. "We worked with a team from MD Anderson Cancer Center to assess the cytocompatibility of fluorinated graphene oxide quantum dots," Radhakrishnan said. "We used a test that measures the metabolic activity of cell cultures and detects toxicity as a drop in metabolic activity. We incubated quantum dots in kidney cell cultures for up to three days and found no significant cell death in the cultures, even at the highest concentrations." The fluorinated graphene oxide quantum dots Radhakrishnan studies can be made in less than a day, but she spent two years perfecting the recipe for them. She begins with micron-sized sheets of graphene that have been fluorinated and oxidized. When these are added to a solvent and stirred for several hours, they break into smaller pieces. Making the material smaller is not difficult, but the process for making small particles with the appropriate magnetic properties is exacting. Radhakrishnan said there was no "eureka moment" in which she suddenly achieved the right results by stumbling on the best formula. Rather, the project was marked by incremental improvements through dozens of minor alterations. "It required a lot of optimization," she said. "The recipe matters a lot." Radhakrishnan said she plans to continue studying the material and hopes to eventually have a hand in proving that it is safe and effective for clinical MRI tests. "I would like to see it applied commercially in clinical ways because it has a lot of advantages compared with conventionally available agents," she said. Additional co-authors include Parambath Sudeep and Chandra Tiwary, both of Rice; Atanu Samanta and Abhishek Singh, both of the Indian Institute of Science at Bangalore; Kiersten Maldonado and Sendurai Mani, both of MD Anderson; and Ghanashyam Acharya of Baylor College of Medicine. The research was supported by the Hamill Foundation through a Hamill Innovation Award to Rice's Institute of Biosciences and Bioengineering, the Air Force Office of Scientific Research, the Indian Institute of Science at Bangalore's Supercomputing Education Research Centre and India's Indo-US Science and Technology Forum. About Rice University Located on a 300-acre forested campus in Houston, Rice University is consistently ranked among the nation’s top 20 universities by U.S. News & World Report. Rice has highly respected schools of Architecture, Business, Continuing Studies, Engineering, Humanities, Music, Natural Sciences and Social Sciences and is home to the Baker Institute for Public Policy. With 3,910 undergraduates and 2,809 graduate students, Rice’s undergraduate student-to-faculty ratio is 6-to-1. Its residential college system builds close-knit communities and lifelong friendships, just one reason why Rice is ranked No. 1 for happiest students and for lots of race/class interaction by the Princeton Review. Rice is also rated as a best value among private universities by Kiplinger’s Personal Finance. To read “What they’re saying about Rice,” go to . Follow Rice News and Media Relations on Twitter @RiceUNews. If you have a comment, please us. Issuers of news releases, not 7th Wave, Inc. or Nanotechnology Now, are solely responsible for the accuracy of the content.

Cassini L.F.,Institute of Biosciences | Cassini L.F.,Federal University of Rio Grande do Sul | Sierra R.O.,Institute of Biosciences | Sierra R.O.,Federal University of Rio Grande do Sul | And 10 more authors.
Hippocampus | Year: 2013

Motivated by the synaptic tagging and capture (STC) hypothesis, it was recently shown that a weak learning, only able to produce short-term memory (STM), can succeed in establishing long-term memory (LTM) with a concomitant, stronger experience. This is consistent with the capture, by the first-tagged event, of the so-called plasticity-related proteins (PRPs) provided by the second one. Here, we describe how a concomitant session of reactivation/reconsolidation of a stronger, contextual fear conditioning (CFC) memory, allowed LTM to result from a weak spatial object recognition (wSOR) training. Consistent with an STC process, the effect was observed only during a critical time window and was dependent on the CFC reconsolidation-related protein synthesis. Retrieval by itself (without reconsolidation) did not have the same promoting effect. We also found that the inactivation of the NMDA receptor by AP5 prevented wSOR training to receive this support of CFC reconsolidation (supposedly through the production of PRPs), which may be the equivalent of blocking the setting of a learning tag in the dorsal CA1 region for that task. Furthermore, either a Water Maze reconsolidation, or a CFC extinction session, allowed the formation of wSOR-LTM. These results suggest for the first time that a reconsolidation session can promote the consolidation of a concomitant weak learning through a probable STC mechanism. These findings allow new insights concerning the influence of reconsolidation in the acquisition of memories of otherwise unrelated events during daily life situations. © 2013 Wiley Periodicals, Inc.

Assalin H.B.,Institute of Biosciences | Rafacho B.P.,Institute of Biosciences | Dos Santos P.P.,Institute of Biosciences | Ardisson L.P.,Institute of Biosciences | And 8 more authors.
Circulation: Heart Failure | Year: 2013

Background-This study was aimed to evaluate the influence of vitamin D (VD) deficiency on cardiac metabolism, morphology, and function. Thus, we investigated the relationship of these changes with the length of the nutrient restriction. Methods and Results-Male weanling Wistar rats were allocated into 4 groups: C2 (n=24), animals were fed an AIN-93G diet with 1000 IU VD/kg of chow and were kept under fluorescent light for 2 months; D2 (n=22), animals were fed a VDdeficient AIN-93G diet and were kept under incandescent light for 2 months; C4 (n=21) animals were kept in the same conditions of C2 for 4 months; and D4 (n=23) animals were kept in the same conditions of D2 for 4 months. Biochemical analyses showed lower β-hydroxyacyl coenzyme-A dehydrogenase activity and higher lactate dehydrogenase activity in VD-deficient animals. Furthermore, VD deficiency was related to increased cytokines release, oxidative stress, apoptosis, and fibrosis. Echocardiographic data showed left ventricular hypertrophy and lower fractional shortening and ejection fraction in VD-deficient animals. Difference became evident in the lactate dehydrogenase activity, left ventricular weight, right ventricle weight, and left ventricular mass after 4 months of VD deficiency. Conclusions-Our data indicate that VD deficiency is associated with energetic metabolic changes, cardiac inflammation, oxidative stress, fibrosis and apoptosis, cardiac hypertrophy, left chambers alterations, and systolic dysfunction. Furthermore, length of the restriction influenced these cardiac changes. © 2013 American Heart Association, Inc.

Cruvinel E.,University of Connecticut Health Center | Cruvinel E.,Institute of Biosciences | Budinetz T.,University of Connecticut Health Center | Germain N.,University of Connecticut Health Center | And 3 more authors.
Human Molecular Genetics | Year: 2014

Prader-Willi syndrome (PWS), a disorder of genomic imprinting, is characterized by neonatal hypotonia, hypogonadism, small hands and feet, hyperphagia and obesity in adulthood. PWS results from the loss of paternal copies of the cluster of SNORD116 C/D box snoRNAs and their host transcript, 116HG, on human chromosome 15q11-q13. We have investigated the mechanism of repression of the maternal SNORD116 cluster and 116HG. Here, we report that the zinc-finger protein ZNF274, in association with the histone H3 lysine 9 (H3K9) methyl transferase SETDB1, is part of a complex that binds to the silent maternal but not the active paternal alleles. Knockdown of SETDB1 in PWS-specific induced pluripotent cells (iPSCs)causes a decrease in the accumulation of H3K9 trimethylation (H3K9me3) at 116HG and corresponding accumulation of the active chromatin mark histone H3 lysine 4 dimethylation (H3K4me2). We also show that upon knockdown of SETDB1 in PWS-specific iPSCs, expression of maternally silenced 116HG RNA is partially restored. SETDB1 knockdown in PWS iPSCs also disrupts DNA methylation at the PWS-IC where a decrease in 5-methylcytosine is observed in association with a concomitant increase in 5-hydroxymethylcytosine. This observation suggests that the ZNF274/SETDB1 complex bound to the SNORD116 cluster may protect the PWS-IC from DNA demethylation during early development. Our findings reveal novel epigenetic mechanisms that function to repress the maternal 15q11-q13 region. © The Author 2014. Published by Oxford University Press. All rights reserved.

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