NobleBlocks

Centro Científico Tecnológico - Bahía Blanca

facilityBahía Blanca, Buenos Aires, Argentina

Research output, citation impact, and the most-cited recent papers from Centro Científico Tecnológico - Bahía Blanca (Argentina). Aggregated across the NobleBlocks index of 300M+ scholarly works.

Total works
4.2K
Citations
124.2K
h-index
107
i10-index
3.2K
Also known as
CONICET Bahía BlancaCentro Científico Tecnológico - Bahía Blanca

Top-cited papers from Centro Científico Tecnológico - Bahía Blanca

Novozym 435: the “perfect” lipase immobilized biocatalyst?
Claudia Ortíz, Marı́a Luján Ferreira, Oveimar Barbosa, José Cleiton Sousa dos Santos +4 more
2019· Catalysis Science & Technology586doi:10.1039/c9cy00415g

Novozym 435 (N435) is a commercially available immobilized lipase produced by Novozymes with its advantages and drawbacks.

Salting our freshwater lakes
Hilary A. Dugan, Sarah L. Bartlett, S. Burke, Jonathan P. Doubek +4 more
2017· Proceedings of the National Academy of Sciences458doi:10.1073/pnas.1620211114

Significance In lakes, chloride is a relatively benign ion at low concentrations but begins to have ecological impacts as concentrations rise into the 100s and 1,000s of mg L −1 . In this study, we investigate long-term chloride trends in 371 freshwater lakes in North America. We find that in Midwest and Northeast North America, most urban lakes and rural lakes that are surrounded by >1% impervious land cover show increasing chloride trends. Expanding on this finding, thousands of lakes in these regions are at risk of long-term salinization. Keeping lakes “fresh” is critically important for protecting the ecosystem services freshwater lakes provide, such as drinking water, fisheries, recreation, irrigation, and aquatic habitat.

The influence of the Plata River discharge on the western South Atlantic shelf
Alberto Piola, Ricardo P. Matano, Elbio D. Palma, Osmar O. Möller +1 more
2005· Geophysical Research Letters394doi:10.1029/2004gl021638

The influence of the Plata, the second largest river in South America, extends along a coastal strip of 1300 km. Historical hydrographic and wind data and numerical simulations are combined to determine the seasonal and interannual variability of the Plata plume and its relationship to the magnitude of the river discharge and the intensity and direction of the wind stress. Our results indicate that the seasonal variability of the river plume is controlled by the alongshore component of the wind stress. During El Niño the effects of the wind and precipitation anomalies tend to compensate each other, preventing anomalous northeastward plume extensions associated to large outflow events. Numerical experiments confirm this finding and indicate that during El Niño the discharge from the Plata River spreads offshore.

The Desired Sensation Level Multistage Input/Output Algorithm
Susan Scollie, Richard C. Seewald, Leonard E. Cornelisse, Sheila Moodie +4 more
2005· Trends in Amplification389doi:10.1177/108471380500900403

The Desired Sensation Level (DSL) Method was revised to support hearing instrument fitting for infants, young children, and adults who use modern hearing instrument technologies, including multichannel compression, expansion, and multimemory capability. The aims of this revision are to maintain aspects of the previous versions of the DSL Method that have been supported by research, while extending the method to account for adult-child differences in preference and listening requirements. The goals of this version (5.0) include avoiding loudness discomfort, selecting a frequency response that meets audibility requirements, choosing compression characteristics that appropriately match technology to the user's needs, and accommodating the overall prescription to meet individual needs for use in various listening environments. This review summarizes the status of research on the use of the DSL Method with pediatric and adult populations and presents a series of revisions that have been made during the generation of DSL v5.0. This article concludes with case examples that illustrate key differences between the DSL v4.1 and DSL v5.0 prescriptions.

Industry 4.0: Smart Scheduling
Daniel Alejandro Rossit, Fernando Tohmé, Mariano Frutos
2018· International Journal of Production Research309doi:10.1080/00207543.2018.1504248

Smart Manufacturing and Industry 4.0 production environments integrate the physical and decisional aspects of manufacturing processes into autonomous and decentralised systems. One of the main aspects in these systems is production planning, in particular scheduling operations on machines. We introduce here a new decision-making schema, Smart Scheduling, intended to yield flexible and efficient production schedules on the fly, taking advantage of the features of these new environments. The ability to face unforeseen and disruptive events is one of the main improvements in our proposed schema, which uses an efficient screening procedure (Tolerance Scheduling) to lessen the need of rescheduling in the face of those events.

Sub-Synchronous Interaction Damping Control for DFIG Wind Turbines
Andrés E. León, Jorge A. Solsona
2014· IEEE Transactions on Power Systems308doi:10.1109/tpwrs.2014.2327197

This paper presents a damping control to mitigate sub-synchronous interactions (SSI) in doubly-fed induction generator (DFIG) wind turbines connected to series-compensated lines. This issue has gained attention due to the recent SSI phenomena reported in DFIG wind farms located near series capacitors. Two approaches which add a supplementary damping control signal are compared: one of them, integrated to the grid-side converter, and the other one, to the rotor-side converter. The SSI damping controls are designed using a multi-input multi-output state-space methodology. This allows to easily tune a high performance controller using several measurements and control inputs. Small- and large-signal stability analyses, robustness aspects, impact of the supplementary controls on the system modes, and influence of different operating conditions on the SSI are also discussed. The obtained results show that the supplementary control is able to properly damp the sub-synchronous oscillations of DFIG wind turbines by updating the existing DFIG control systems without the inclusion of expensive additional damping devices, and reducing the risk of wind generation tripping.

Ecosystem Services as a Common Language for Coastal Ecosystem‐Based Management
Elise F. Granek, Stephen Polasky, Carrie V. Kappel, Denise J. Reed +4 more
2009· Conservation Biology305doi:10.1111/j.1523-1739.2009.01355.x

Ecosystem-based management is logistically and politically challenging because ecosystems are inherently complex and management decisions affect a multitude of groups. Coastal ecosystems, which lie at the interface between marine and terrestrial ecosystems and provide an array of ecosystem services to different groups, aptly illustrate these challenges. Successful ecosystem-based management of coastal ecosystems requires incorporating scientific information and the knowledge and views of interested parties into the decision-making process. Estimating the provision of ecosystem services under alternative management schemes offers a systematic way to incorporate biogeophysical and socioeconomic information and the views of individuals and groups in the policy and management process. Employing ecosystem services as a common language to improve the process of ecosystem-based management presents both benefits and difficulties. Benefits include a transparent method for assessing trade-offs associated with management alternatives, a common set of facts and common currency on which to base negotiations, and improved communication among groups with competing interests or differing worldviews. Yet challenges to this approach remain, including predicting how human interventions will affect ecosystems, how such changes will affect the provision of ecosystem services, and how changes in service provision will affect the welfare of different groups in society. In a case study from Puget Sound, Washington, we illustrate the potential of applying ecosystem services as a common language for ecosystem-based management.

Creatinine clearance and adverse hospital outcomes in patients with acute coronary syndromes: findings from the global registry of acute coronary events (GRACE)
José Santopinto, K A A Fox, R J Goldberg, A Budaj +4 more
2003· Heart297doi:10.1136/heart.89.9.1003

OBJECTIVE: To determine whether creatinine clearance at the time of hospital admission is an independent predictor of hospital mortality and adverse outcomes in patients with acute coronary syndromes (ACS). DESIGN: A prospective multicentre observational study, GRACE (global registry of acute coronary events), of patients with the full spectrum of ACS. SETTING: Ninety four hospitals of varying size and capability in 14 countries across four continents. PATIENTS: 11 774 patients hospitalised with ACS, including ST and non-ST segment elevation acute myocardial infarction and unstable angina. MAIN OUTCOME MEASURES: Demographic and clinical characteristics, medication use, and in-hospital outcomes were compared for patients with creatinine clearance rates of > 60 ml/min (normal and minimally impaired renal function), 30-60 ml/min (moderate renal dysfunction), and < 30 ml/min (severe renal dysfunction). RESULTS: Patients with moderate or severe renal dysfunction were older, were more likely to be women, and presented to participating hospitals with more comorbidities than those with normal or minimally impaired renal function. In comparison with patients with normal or minimally impaired renal function, patients with moderate renal dysfunction were twice as likely to die (odds ratio 2.09, 95% confidence interval 1.55 to 2.81) and those with severe renal dysfunction almost four times more likely to die (odds ratio 3.71, 95% confidence interval 2.57 to 5.37) after adjustment for other potentially confounding variables. The risk of major bleeding episodes increased as renal function worsened. CONCLUSION: In patients with ACS, creatinine clearance is an important independent predictor of hospital death and major bleeding. These data reinforce the importance of increased surveillance efforts and use of targeted intervention strategies in patients with acute coronary disease complicated by renal dysfunction.

Biomedical Applications of Iron Oxide Nanoparticles: Current Insights Progress and Perspectives
M. Schneider, María Julia Martín, Jessica Otarola, Ekaterina Vakarelska +3 more
2022· Pharmaceutics281doi:10.3390/pharmaceutics14010204

The enormous development of nanomaterials technology and the immediate response of many areas of science, research, and practice to their possible application has led to the publication of thousands of scientific papers, books, and reports. This vast amount of information requires careful classification and order, especially for specifically targeted practical needs. Therefore, the present review aims to summarize to some extent the role of iron oxide nanoparticles in biomedical research. Summarizing the fundamental properties of the magnetic iron oxide nanoparticles, the review's next focus was to classify research studies related to applying these particles for cancer diagnostics and therapy (similar to photothermal therapy, hyperthermia), in nano theranostics, multimodal therapy. Special attention is paid to research studies dealing with the opportunities of combining different nanomaterials to achieve optimal systems for biomedical application. In this regard, original data about the synthesis and characterization of nanolipidic magnetic hybrid systems are included as an example. The last section of the review is dedicated to the capacities of magnetite-based magnetic nanoparticles for the management of oncological diseases.

COVID-19 pandemic repercussions on plastic and antiviral polymeric textile causing pollution on beaches and coasts of South America
M.G. Ardusso, Ana D. Forero López, Natalia S. Buzzi, Carla V. Spetter +1 more
2020· The Science of The Total Environment256doi:10.1016/j.scitotenv.2020.144365

The propagation of the COVID-19 pandemic worldwide has been alarming in the last months. According to recommendations of the World Health Organization (WHO), the use of face masks is essential for slowing down the transmission rate of COVID-19 in human beings. This pandemic has generated a substantial increase in the use, as well as in the production, of face masks and other elements (gloves, face protectors, protective suits, safety shoes) manufactured with polymeric materials, including antiviral textiles most of which will end as microplastic pools. Focusing on South America, the use and mismanagement of this type of personal protective equipment (PPE) represents an environmental problem. Added to this issue are the increase in the use of single-use plastic, and the reduction of plastic recycling due to the curfew generated by the pandemic, further aggravating plastic pollution on coasts and beaches. Recently, researchers have developed antiviral polymeric textile technology composed of Ag and Cu nanoparticles for PPE to reduce the contagion and spread of COVID-19. Antiviral polymeric textile wastes could also have long-term negative repercussions on aquatic environments, as they are an important emerging class of contaminants. For this reason, this work provides reflections and perspectives on how the COVID-19 pandemic can aggravate plastic pollution on beaches and coastal environments, consequently increasing the damage to marine species in the coming years. In addition, the potential impact of the pandemic on waste management systems is discussed here, as well as future research directions to improve integrated coastal management strategies.

Disclosure of cholesterol recognition motifs in transmembrane domains of the human nicotinic acetylcholine receptor
Carlos Javier Baier, Jacques Fantini, Francisco J. Barrantes
2011· Scientific Reports248doi:10.1038/srep00069

Cholesterol influences ion-channel function, distribution and clustering in the membrane, endocytosis, and exocytic sorting of the nicotinic acetylcholine receptor (AChR). We report the occurrence of a cholesterol recognition motif, here coined "CARC", in the transmembrane regions of AChR subunits that bear extensive contact with the surrounding lipid, and are thus optimally suited to convey cholesterol-mediated signaling from the latter. Three cholesterol molecules could be docked on the transmembrane segments of each AChR subunit, rendering a total of 15 cholesterol molecules per AChR molecule. The CARC motifs contribute each with an energy of interaction between 35 and 52 kJ.mol(-1), adding up to a total of about 200 kJ.mol(-1) per receptor molecule, i.e. ∼40% of the lipid solvation free energy/ AChR molecule. The CARC motif is remarkably conserved along the phylogenetic scale, from prokaryotes to human, suggesting that it could be responsible for some of the above structural/functional properties of the AChR.

The ocean sampling day consortium
Anna Kopf, Mesude Bicak, Renzo Kottmann, Julia Schnetzer +4 more
2015· GigaScience222doi:10.1186/s13742-015-0066-5

Ocean Sampling Day was initiated by the EU-funded Micro B3 (Marine Microbial Biodiversity, Bioinformatics, Biotechnology) project to obtain a snapshot of the marine microbial biodiversity and function of the world's oceans. It is a simultaneous global mega-sequencing campaign aiming to generate the largest standardized microbial data set in a single day. This will be achievable only through the coordinated efforts of an Ocean Sampling Day Consortium, supportive partnerships and networks between sites. This commentary outlines the establishment, function and aims of the Consortium and describes our vision for a sustainable study of marine microbial communities and their embedded functional traits.

Molecular reorganization of endocannabinoid signalling in Alzheimer’s disease
Jan Mulder, Misha Zilberter, Susana J. Pasquaré, Alán Alpár +4 more
2011· Brain212doi:10.1093/brain/awr046

Retrograde messengers adjust the precise timing of neurotransmitter release from the presynapse, thus modulating synaptic efficacy and neuronal activity. 2-Arachidonoyl glycerol, an endocannabinoid, is one such messenger produced in the postsynapse that inhibits neurotransmitter release upon activating presynaptic CB(1) cannabinoid receptors. Cognitive decline in Alzheimer's disease is due to synaptic failure in hippocampal neuronal networks. We hypothesized that errant retrograde 2-arachidonoyl glycerol signalling impairs synaptic neurotransmission in Alzheimer's disease. Comparative protein profiling and quantitative morphometry showed that overall CB(1) cannabinoid receptor protein levels in the hippocampi of patients with Alzheimer's disease remain unchanged relative to age-matched controls, and CB(1) cannabinoid receptor-positive presynapses engulf amyloid-β-containing senile plaques. Hippocampal protein concentrations for the sn-1-diacylglycerol lipase α and β isoforms, synthesizing 2-arachidonoyl glycerol, significantly increased in definite Alzheimer's (Braak stage VI), with ectopic sn-1-diacylglycerol lipase β expression found in microglia accumulating near senile plaques and apposing CB(1) cannabinoid receptor-positive presynapses. We found that microglia, expressing two 2-arachidonoyl glycerol-degrading enzymes, serine hydrolase α/β-hydrolase domain-containing 6 and monoacylglycerol lipase, begin to surround senile plaques in probable Alzheimer's disease (Braak stage III). However, Alzheimer's pathology differentially impacts serine hydrolase α/β-hydrolase domain-containing 6 and monoacylglycerol lipase in hippocampal neurons: serine hydrolase α/β-hydrolase domain-containing 6 expression ceases in neurofibrillary tangle-bearing pyramidal cells. In contrast, pyramidal cells containing hyperphosphorylated tau retain monoacylglycerol lipase expression, although at levels significantly lower than in neurons lacking neurofibrillary pathology. Here, monoacylglycerol lipase accumulates in CB(1) cannabinoid receptor-positive presynapses. Subcellular fractionation revealed impaired monoacylglycerol lipase recruitment to biological membranes in post-mortem Alzheimer's tissues, suggesting that disease progression slows the termination of 2-arachidonoyl glycerol signalling. We have experimentally confirmed that altered 2-arachidonoyl glycerol signalling could contribute to synapse silencing in Alzheimer's disease by demonstrating significantly prolonged depolarization-induced suppression of inhibition when superfusing mouse hippocampi with amyloid-β. We propose that the temporal dynamics and cellular specificity of molecular rearrangements impairing 2-arachidonoyl glycerol availability and actions may differ from those of anandamide. Thus, enhanced endocannabinoid signalling, particularly around senile plaques, can exacerbate synaptic failure in Alzheimer's disease.

Fungal Planet description sheets: 1042–1111
P.W. Crous, Michael J. Wingfield, Yit‐Heng Chooi, Cameron L. M. Gilchrist +4 more
2020· Persoonia - Molecular Phylogeny and Evolution of Fungi182doi:10.3767/persoonia.2020.44.11

Novel species of fungi described in this study include those from various countries as follows: Antarctica , Cladosporium arenosum from marine sediment sand. Argentina , Kosmimatamyces alatophylus (incl. Kosmimatamyces gen. nov.) from soil. Australia , Aspergillus banksianus , Aspergillus kumbius , Aspergillus luteorubrus , Aspergillus malvicolor and Aspergillus nanangensis from soil, Erysiphe medicaginis from leaves of Medicago polymorpha , Hymenotorrendiella communis on leaf litter of Eucalyptus bicostata , Lactifluus albopicri and Lactifluus austropiperatus on soil, Macalpinomyces collinsiae on Eriachne benthamii , Marasmius vagus on soil, Microdochium dawsoniorum from leaves of Sporobolus natalensis , Neopestalotiopsis nebuloides from leaves of Sporobolus elongatus , Pestalotiopsis etonensis from leaves of Sporobolus jacquemontii , Phytophthora personensis from soil associated with dying Grevillea mccutcheonii. Brazil , Aspergillus oxumiae from soil, Calvatia baixaverdensis on soil, Geastrum calycicoriaceum on leaf litter, Greeneria kielmeyerae on leaf spots of Kielmeyera coriacea . Chile , Phytophthora aysenensis on collar rot and stem of Aristotelia chilensis . Croatia , Mollisia gibbospora on fallen branch of Fagus sylvatica . Czech Republic , Neosetophoma hnaniceana from Buxus sempervirens . Ecuador , Exophiala frigidotolerans from soil. Estonia , Elaphomyces bucholtzii in soil. France , Venturia paralias from leaves of Euphorbia paralias . India , Cortinarius balteatoindicus and Cortinarius ulkhagarhiensis on leaf litter. Indonesia , Hymenotorrendiella indonesiana on Eucalyptus urophylla leaf litter. Italy , Penicillium taurinense from indoor chestnut mill. Malaysia , Hemileucoglossum kelabitense on soil, Satchmopsis pini on dead needles of Pinus tecunumanii . Poland , Lecanicillium praecognitum on insects' frass. Portugal , Neodevriesia aestuarina from saline water. Republic of Korea , Gongronella namwonensis from freshwater. Russia , Candida pellucida from Exomias pellucidus , Heterocephalacria septentrionalis as endophyte from Cladonia rangiferina , Vishniacozyma phoenicis from dates fruit, Volvariella paludosa from swamp. Slovenia , Mallocybe crassivelata on soil. South Africa , Beltraniella podocarpi , Hamatocanthoscypha podocarpi , Coleophoma podocarpi and Nothoseiridium podocarpi (incl. Nothoseiridium gen. nov.)from leaves of Podocarpus latifolius , Gyrothrix encephalarti from leaves of Encephalartos sp., Paraphyton cutaneum from skin of human patient, Phacidiella alsophilae from leaves of Alsophila capensis , and Satchmopsis metrosideri on leaf litter of Metrosideros excelsa. Spain , Cladophialophora cabanerensis from soil, Cortinarius paezii on soil, Cylindrium magnoliae from leaves of Magnolia grandiflora , Trichophoma cylindrospora (incl. Trichophoma gen. nov.) from plant debris, Tuber alcaracense in calcareus soil, Tuber buendiae in calcareus soil. Thailand , Annulohypoxylon spougei on corticated wood, Poaceascoma filiforme from leaves of unknown Poaceae. UK , Dendrostoma luteum on branch lesions of Castanea sativa , Ypsilina buttingtonensis from heartwood of Quercus sp. Ukraine , Myrmecridium phragmiticola from leaves of Phragmites australis. USA , Absidia pararepens from air, Juncomyces californiensis (incl. Juncomyces gen. nov.) from leaves of Juncus effusus , Montagnula cylindrospora from a human skin sample, Muriphila oklahomaensis (incl. Muriphila gen. nov.)on outside wall of alcohol distillery, Neofabraea eucalyptorum from leaves of Eucalyptus macrandra , Diabolocovidia claustri (incl. Diabolocovidia gen. nov.)from leaves of Serenoa repens , Paecilomyces penicilliformis from air, Pseudopezicula betulae from leaves of leaf spots of Populus tremuloides . Vietnam , Diaporthe durionigena on branches of Durio zibethinus and Roridomyces pseudoirritans on rotten wood. Morphological and culture characteristics are supported by DNA barcodes.

A functional definition to distinguish ponds from lakes and wetlands
David C. Richardson, Meredith A. Holgerson, Matthew J. Farragher, Kathryn K. Hoffman +4 more
2022· Scientific Reports170doi:10.1038/s41598-022-14569-0

Ponds are often identified by their small size and shallow depths, but the lack of a universal evidence-based definition hampers science and weakens legal protection. Here, we compile existing pond definitions, compare ecosystem metrics (e.g., metabolism, nutrient concentrations, and gas fluxes) among ponds, wetlands, and lakes, and propose an evidence-based pond definition. Compiled definitions often mentioned surface area and depth, but were largely qualitative and variable. Government legislation rarely defined ponds, despite commonly using the term. Ponds, as defined in published studies, varied in origin and hydroperiod and were often distinct from lakes and wetlands in water chemistry. We also compared how ecosystem metrics related to three variables often seen in waterbody definitions: waterbody size, maximum depth, and emergent vegetation cover. Most ecosystem metrics (e.g., water chemistry, gas fluxes, and metabolism) exhibited nonlinear relationships with these variables, with average threshold changes at 3.7 ± 1.8 ha (median: 1.5 ha) in surface area, 5.8 ± 2.5 m (median: 5.2 m) in depth, and 13.4 ± 6.3% (median: 8.2%) emergent vegetation cover. We use this evidence and prior definitions to define ponds as waterbodies that are small (< 5 ha), shallow (< 5 m), with < 30% emergent vegetation and we highlight areas for further study near these boundaries. This definition will inform the science, policy, and management of globally abundant and ecologically significant pond ecosystems.

Democratic Particle Motion for Metabasin Transitions in Simple Glass Formers
Gustavo A. Appignanesi, J. A. Rodríguez Fris, R.A. Montani, Walter Kob
2006· Physical Review Letters167doi:10.1103/physrevlett.96.057801

We use molecular dynamics computer simulations to investigate the local motion of the particles in a supercooled binary liquid. Using the concept of the distance matrix, we find that the alpha relaxation corresponds to a small number of crossings from one metabasin to a neighboring one. Each crossing is very rapid and involves the collective motion of O(40) particles that form a relatively compact cluster, whereas stringlike motions seem not to be relevant for these transitions. These compact clusters are thus potential candidates for the cooperatively rearranging regions proposed a long time ago by Adam and Gibbs.

Computer‐aided molecular design of solvents for separation processes
Eduardo J. Pretel, Patricio Araya López, Susana B. Bottini, Esteban A. Brignole
1994· AIChE Journal161doi:10.1002/aic.690400808

Abstract The search for potential solvents for liquid extraction and extractive distillation is carried out through a group contribution molecular design of solvents (MOLDES) approach. A set of submolecular groups (UNIFAC) is used for the synthesis of molecular structures with desired solvent properties. Submolecular group combination (linking) properties are characterized to ensure the chemical feasibility of the MOLDES generated molecular structures. The size of the combinatorial problem posed by the molecular synthesis procedure is reduced by group selection and by imposing physical and molecular constraints at different stages. Criteria are developed for solvent evaluation and the reliability of the VLE and the LLE UNIFAC parameter tables for solvent screening are compared with experimental data for the recovery of oxychemicals by liquid extraction from dilute aqueous solutions.

Alzheimer’s Disease as a Membrane Disorder: Spatial Cross-Talk Among Beta-Amyloid Peptides, Nicotinic Acetylcholine Receptors and Lipid Rafts
Camila Fabiani, Silvia S. Antollini
2019· Frontiers in Cellular Neuroscience150doi:10.3389/fncel.2019.00309

Biological membranes show lateral and transverse asymmetric lipid distribution. Cholesterol (Chol) localizes in both hemilayers, but in the external one it is mostly condensed in lipid-ordered microdomains (raft domains), together with saturated phosphatidyl lipids and sphingolipids (including sphingomyelin and glycosphingolipids). Membrane asymmetries induce special membrane biophysical properties and behave as signals for several physiological and/or pathological processes. Alzheimer's disease (AD) is associated with a perturbation in different membrane properties. Amyloid-β (Aβ) plaques and neurofibrillary tangles of tau protein together with neuroinflammation and neurodegeneration are the most characteristic cellular changes observed in this disease. The extracellular presence of Aβ peptides forming senile plaques, together with soluble oligomeric species of Aβ, are considered the major cause of the synaptic dysfunction of AD. The association between Aβ peptide and membrane lipids has been extensively studied. It has been postulated that Chol content and Chol distribution condition Aβ production and posterior accumulation in membranes and, hence, cell dysfunction. Several lines of evidence suggest that Aβ partitions in the cell membrane accumulate mostly in raft domains, the site where the cleavage of the precursor AβPP by β- and γ- secretase is also thought to occur. The main consequence of the pathogenesis of AD is the disruption of the cholinergic pathways in the cerebral cortex and in the basal forebrain. In parallel, the nicotinic acetylcholine receptor has been extensively linked to membrane properties. Since its transmembrane domain exhibits extensive contacts with the surrounding lipids, the acetylcholine receptor function is conditioned by its lipid microenvironment. The nicotinic acetylcholine receptor is present in high-density clusters in the cell membrane where it localizes mainly in lipid-ordered domains. Perturbations of sphingomyelin or cholesterol composition alter acetylcholine receptor location. Therefore, Aβ processing, Aβ partitioning, and acetylcholine receptor location and function can be manipulated by changes in membrane lipid biophysics. Understanding these mechanisms should provide insights into new therapeutic strategies for prevention and/or treatment of AD. Here, we discuss the implications of lipid-protein interactions at the cell membrane level in AD.

Heterogeneity in Genetic Admixture across Different Regions of Argentina
Sergio Alejandro Avena, Marc Vía, Elad Ziv, Eliseo J. Pérez‐Stable +4 more
2012· PLoS ONE143doi:10.1371/journal.pone.0034695

The population of Argentina is the result of the intermixing between several groups, including Indigenous American, European and African populations. Despite the commonly held idea that the population of Argentina is of mostly European origin, multiple studies have shown that this process of admixture had an impact in the entire Argentine population. In the present study we characterized the distribution of Indigenous American, European and African ancestry among individuals from different regions of Argentina and evaluated the level of discrepancy between self-reported grandparental origin and genetic ancestry estimates. A set of 99 autosomal ancestry informative markers (AIMs) was genotyped in a sample of 441 Argentine individuals to estimate genetic ancestry. We used non-parametric tests to evaluate statistical significance. The average ancestry for the Argentine sample overall was 65% European (95%CI: 63-68%), 31% Indigenous American (28-33%) and 4% African (3-4%). We observed statistically significant differences in European ancestry across Argentine regions [Buenos Aires province (BA) 76%, 95%CI: 73-79%; Northeast (NEA) 54%, 95%CI: 49-58%; Northwest (NWA) 33%, 95%CI: 21-41%; South 54%, 95%CI: 49-59%; p<0.0001] as well as between the capital and immediate suburbs of Buenos Aires city compared to more distant suburbs [80% (95%CI: 75-86%) versus 68% (95%CI: 58-77%), p = 0.01]. European ancestry among individuals that declared all grandparents born in Europe was 91% (95%CI: 88-94%) compared to 54% (95%CI: 51-57%) among those with no European grandparents (p<0.001). Our results demonstrate the range of variation in genetic ancestry among Argentine individuals from different regions in the country, highlighting the importance of taking this variation into account in genetic association and admixture mapping studies in this population.

<i>Burkholderia cepacia</i> lipase: A versatile catalyst in synthesis reactions
Daniel Alberto Sánchez, Gabriela Marta Tonetto, Marı́a Luján Ferreira
2017· Biotechnology and Bioengineering133doi:10.1002/bit.26458

The lipase from Burkholderia cepacia, formerly known as Pseudomonas cepacia lipase, is a commercial enzyme in both soluble and immobilized forms widely recognized for its thermal resistance and tolerance to a large number of solvents and short-chain alcohols. The main applications of this lipase are in transesterification reactions and in the synthesis of drugs (because of the properties mentioned above). This review intends to show the features of this enzyme and some of the most relevant aspects of its use in different synthesis reactions. Also, different immobilization techniques together with the effect of various compounds on lipase activity are presented. This lipase shows important advantages over other lipases, especially in reaction media including solvents or reactions involving short-chain alcohols.