排序方式: 共有19条查询结果,搜索用时 15 毫秒
1.
Jeroen de Ridder Pieter Meysman Olugbenga Oluwagbemi Thomas Abeel 《PLoS computational biology》2014,10(7)
Contributing to a student organization, such as the International Society for Computational Biology Student Council (ISCB-SC) and its Regional Student Group (RSG) program, takes time and energy. Both are scarce commodities, especially when you are trying to find your place in the world of computational biology as a graduate student. It comes as no surprise that organizing ISCB-SC-related activities sometimes interferes with day-to-day research and shakes up your priority list. However, we unanimously agree that the rewards, both in the short as well as the long term, make the time spent on these extracurricular activities more than worth it. In this article, we will explain what makes this so worthwhile: soft skills. 相似文献
2.
Computational biology and bioinformatics are gradually gaining grounds in Africa and other developing nations of the world.
However, in these countries, some of the challenges of computational biology and bioinformatics education are inadequate
infrastructures, and lack of readily-available complementary and motivational tools to support learning as well as research. This
has lowered the morale of many promising undergraduates, postgraduates and researchers from aspiring to undertake future
study in these fields. In this paper, we developed and described MACBenAbim (Multi-platform Mobile Application for Computational
Biology and Bioinformatics), a flexible user-friendly tool to search for, define and describe the meanings of keyterms in computational
biology and bioinformatics, thus expanding the frontiers of knowledge of the users. This tool also has the capability of achieving
visualization of results on a mobile multi-platform context.
Availability
MACBenAbim is available from the authors for non-commercial purposes. 相似文献3.
We demonstrate that 5,5'-dithiobis(2-nitrobenzoate) - DTNB - reacts with only CysF9[93]beta and CysB5[23]beta among the multiple sulfhydryl groups of the major and minor hemoglobins of the Japanese quail (Cortunix cortunix japonica). K(equ), the equilibrium constant for the reaction, does not differ very significantly between the two hemoglobins. It decreases 430-fold between pH approximately 5.6 and pH approximately 9: from a mean of 7+/-1 to a mean of 0.016+/-0.003. Quantitative analyses of the K(equ) data based on published X-ray and temperature-jump evidence for a tertiary structure transition in liganded hemoglobin enable the calculation of K(rt), the equilibrium constant for the r<---->t tertiary structure transition. K(rt) differs significantly between the two hemoglobins: 0.744+/-0.04 for the major, 0.401+/-0.01 for the minor hemoglobin. The mean pK(a)s of the two groups whose ionizations are coupled to the DTNB reaction are about the same as previously reported for mammalian hemoglobins. 相似文献
4.
5.
Olugbenga Solomon Bello Bukola Morenike Lasisi Olamide Joshua Adigun Vunain Ephraim 《Chemical Speciation and Bioavailability》2017,29(1):120-134
Moringa oliferia seed pod was modified using orthophosphoric acid (H3PO4) and used as adsorbent for sequestering Rhodamine B (Rh-B) dye from aqueous solution. The acid-modified adsorbent (MOSPAC) was characterized using Scanning Electron microscopy (SEM), Fourier Transform Infra Red (FTIR), Energy Dispersive X-ray (EDX), pH point of zero charge (pHpzc) and Boehm Titration (BT) techniques, respectively. Operational parameters such as contact time, initial dye concentration, adsorbent dosage, pH and solution temperature were studied in batch process. Optimum dye adsorption was observed at pH 3.01. Equilibrium adsorption data was tested data using four different isotherm models: Langmuir, Freundlich, Temkin and Dubinin-Radushkevich. Langmuir isotherm model fitted most with maximum monolayer adsorption capacity of 1250 mg g–1. Pseudo-second-order kinetic model provided the best correlation for the experimental data. Thermodynamic study showed that the process is endothermic, spontaneous and feasible. MOSPAC is an effective adsorbent for the removal of RhB dye from aqueous solutions. 相似文献
6.
Wang Z Ferdousy F Lawal H Huang Z Daigle JG Izevbaye I Doherty O Thomas J Stathakis DG O'Donnell JM 《Journal of neurochemistry》2011,119(6):1294-1305
The highly reactive nature of dopamine renders dopaminergic neurons vulnerable to oxidative damage. We recently demonstrated that loss-of-function mutations in the Drosophila gene Catecholamines up (Catsup) elevate dopamine pools but, paradoxically, also confer resistance to paraquat, an herbicide that induces oxidative stress-mediated toxicity in dopaminergic neurons. We now report a novel association of the membrane protein, Catsup, with GTP cyclohydrolase rate-limiting enzyme for tetrahydrobiopterin (BH(4)) biosynthesis and tyrosine hydroxylase, rate-limiting enzyme for dopamine biosynthesis, which requires BH(4) as a cofactor. Loss-of-function Catsup mutations cause dominant hyperactivation of both enzymes. Elevated dopamine levels in Catsup mutants coincide with several distinct characteristics, including hypermobility, minimal basal levels of 3,4-dihydroxy-phenylacetic acid, an oxidative metabolite of dopamine, and resistance to the vesicular monoamine transporter inhibitor, reserpine, suggesting that excess dopamine is synaptically active and that Catsup functions in the regulation of synaptic vesicle loading and release of dopamine. We conclude that Catsup regulates and links the dopamine synthesis and transport networks. 相似文献
7.
Wakabayashi-Ito N Doherty OM Moriyama H Breakefield XO Gusella JF O'Donnell JM Ito N 《PloS one》2011,6(10):e26183
Dystonia represents the third most common movement disorder in humans. At least 15 genetic loci (DYT1-15) have been identified and some of these genes have been cloned. TOR1A (formally DYT1), the gene responsible for the most common primary hereditary dystonia, encodes torsinA, an AAA ATPase family protein. However, the function of torsinA has yet to be fully understood. Here, we have generated and characterized a complete loss-of-function mutant for dtorsin, the only Drosophila ortholog of TOR1A. Null mutation of the X-linked dtorsin was semi-lethal with most male flies dying by the pre-pupal stage and the few surviving adults being sterile and slow moving, with reduced cuticle pigmentation and thin, short bristles. Third instar male larvae exhibited locomotion defects that were rescued by feeding dopamine. Moreover, biochemical analysis revealed that the brains of third instar larvae and adults heterozygous for the loss-of-function dtorsin mutation had significantly reduced dopamine levels. The dtorsin mutant showed a very strong genetic interaction with Pu (Punch: GTP cyclohydrolase), the ortholog of the human gene underlying DYT14 dystonia. Biochemical analyses revealed a severe reduction of GTP cyclohydrolase protein and activity, suggesting that dtorsin plays a novel role in dopamine metabolism as a positive-regulator of GTP cyclohydrolase protein. This dtorsin mutant line will be valuable for understanding this relationship and potentially other novel torsin functions that could play a role in human dystonia. 相似文献
8.
Beta-cyanoalanine synthase (beta-cyano-l-alanine synthase; l-cysteine: hydrogen sulphide lyase (adding hydrogen cyanide (HCN)); EC 4. 4.1.9) was purified from the cytosolic fraction of the gut of grasshopper Zonocerus variegatus (L.) by ion-exchange chromatography on DEAE-Cellulose and gel filtration on Sephadex G-100 columns. The crude enzyme had a specific activity of 2.16nmol H2S/min/mg. A purified enzyme with a specific activity, which was seventeen times higher than that of the crude extract, was obtained. A molecular weight of about 55.23+/-1.00Kd was estimated from its elution volume on Sephadex G-100. The fraction when subjected to sodium dodecyl sulphate-polyacrylamide elel electrophoresis revealed the presence of a protein band with Mr of 23.25+/-0.25Kd. The enzyme exhibited Michaelis-Menten kinetics having Km of 0.38mM for l-cysteine and Km of 6.25mM for cyanide. The optimum temperature and pH for activity were determined to be at 30 degrees C and pH 9.0, respectively. This enzyme might be responsible for the ability to detoxify cyanide in this insect pest and hence its tolerance of the cyanogenic cassava plant. Biophysical, biochemical and kinetic properties of this enzyme, which will reveal how this ability can possibly be compromised by enzyme inhibition, may lead, in the long term, to the potential use of this enzyme as drug target for pest control. 相似文献
9.
David Holt Olugbenga Okusanya Ryan Judy Ollin Venegas Jack Jiang Elizabeth DeJesus Evgeniy Eruslanov Jon Quatromoni Pratik Bhojnagarwala Charuhas Deshpande Steven Albelda Shuming Nie Sunil Singhal 《PloS one》2014,9(7)
Introduction
Defining tumor from non-tumor tissue is one of the major challenges of cancer surgery. Surgeons depend on visual and tactile clues to select which tissues should be removed from a patient. Recently, we and others have hypothesized near-infrared (NIR) imaging can be used during surgery to differentiate tumors from normal tissue.Methods
We enrolled 8 canines and 5 humans undergoing cancer surgery for NIR imaging. The patients were injected with indocyanine green (ICG), an FDA approved non-receptor specific NIR dye that accumulates in hyperpermeable tissues, 16–24 hours prior to surgery. During surgery, NIR imaging was used to discriminate the tumor from non-tumor tissue.Results
NIR imaging identified all tumors with a mean signal-to-background ratio of 6.7. Optical images were useful during surgery in discriminating normal tissue from cancer. In 3 canine cases and 1 human case, the tissue surrounding the tumor was inflamed due to obstruction of the vascular supply due to mass effect. In these instances, NIR imaging could not distinguish tumor tissue from tissue that was congested, edematous and did not contain cancer.Conclusions
This study shows that NIR imaging can identify tumors from normal tissues, provides excellent tissue contrast, and it facilitates the resection of tumors. However, in situations where there is significant peritumoral inflammation, NIR imaging with ICG is not helpful. This suggests that non-targeted NIR dyes that accumulate in hyperpermeable tissues will have significant limitations in the future, and receptor-specific NIR dyes may be necessary to overcome this problem. 相似文献10.
Coral reefs are now subject to global threats and influences from numerous anthropogenic sources. Foraminifera, a group of unicellular shelled organisms, are excellent indicators of water quality and reef health. Thus we studied a set of samples taken in 1992 to provide a foraminiferal baseline for future studies of environmental change. Our study provides the first island-wide analysis of shallow benthic foraminifera from around Moorea (Society Archipelago). We analyzed the composition, species richness, patterns of distribution and abundance of unstained foraminiferal assemblages from bays, fringing reefs, nearshore and back- and fore-reef environments. A total of 380 taxa of foraminifera were recorded, a number that almost doubles previous species counts. Spatial patterns of foraminiferal assemblages are characterized by numerical abundances of individual taxa, cluster groups and gradients of species richness, as documented by cluster, Fisher α, ternary plot and Principal Component Analyses (PCA). The inner bay inlets are dominated by stress-tolerant, mostly thin-shelled taxa of Bolivina, Bolivinella, Nonionoides, Elongobula, and Ammonia preferring low-oxygen and/or nutrient-rich habitats influenced by coastal factors such as fresh-water runoff and overhanging mangroves. The larger symbiont-bearing foraminifera (Borelis, Amphistegina, Heterostegina, Peneroplis) generally live in the oligotrophic, well-lit back- and fore-reef environments. Amphisteginids and peneroplids were among the few taxa found in the bay environments, probably due to their preferences for phytal substrates and tolerance to moderate levels of eutrophication. The fringing reef environments along the outer bay are characterized by Borelis schlumbergeri, Heterostegina depressa, Textularia spp. and various miliolids which represent a hotspot of diversity within the complex reef-lagoon system of Moorea. The high foraminiferal Fisher α and species richness diversity in outer bay fringing reefs is consistent with the disturbance-mosaic (microhabitat heterogeneity) hypothesis.Calculations of the FORAM Index (FI), a single metric index to assess reef vitality, indicate that all fore- and most back-reef environments support active carbonate accretion and provide habitat suitability for carbonate producers dependent on algal symbiosis. Lowest suitability values were recorded within the innermost bays, an area where natural and increasing anthropogenic influences continue to impact the reefs. The presence of habitat specific assemblages and numerical abundance values of individual taxa show that benthic foraminifera are excellent recorders of environmental perturbations and good indicators useful in modern and ancient ecological and environmental studies. 相似文献