Effects of chronic exercise on severity, quality of life and functionality in an elderly Parkinson’s disease patient: case report

Exercise produces potential influences on physical and mental capacity in patients with neuropsychiatric disor- ders, and can be made a viable form of therapy to treat Parkinson’s disease (PD). We report the chronic effects of a regu- lar physical exercise protocol on cognitive and motor functions, functional capacity, and symptoms in an elderly PD pa- tient without dementia. The patient participated of a program composed of proprioceptive, aerobic and flexibility exer- cises, during 1 hour, three days a week, for nine months. Patient used 600 mg of L-DOPA daily, and 1 hour prior to each exercise session. Assessment was conducted in three stages, 0-3, 3-6 and 6 to 9 months, using percentual variation to the scales Hoehn and Yahr, Mini-Mental State Examination (MMSE), Parkinson Activity Scale (PAS), Beck Depression In- ventory (BDI), and Unified Parkinson's Disease Rating Scale (UPDRS-III). Reassessment showed clear changes in clini- cal parameters for Hoehn and Yahr (4 to 2.5), MMSE (14 to 22), PAS (13 to 29), BDI (9 to 7) and UPDRS-III (39 to 27) at the end of 9 months. According to our data, exercise seems to be effective in promoting the functional capacity and the maintenance of cognitive and motor functions of PD patients. Regular exercise protocols can be implemented as an ad- junctive treatment for reducing the severity of PD

Mesoscopic model for DNA G-quadruplex unfolding

[EN] Genomes contain rare guanine-rich sequences capable of assembling into four-stranded helical structures, termed G-quadruplexes, with potential roles in gene regulation and chromosome stability. Their mechanical unfolding has only been reported to date by all-atom simulations, which cannot dissect the major physical interactions responsible for their cohesion. Here, we propose a mesoscopic model to describe both the mechanical and thermal stability of DNA G-quadruplexes, where each nucleotide of the structure, as well as each central cation located at the inner channel, is mapped onto a single bead. In this framework we are able to simulate loading rates similar to the experimental ones, which are not reachable in simulations with atomistic resolution. In this regard, we present single-molecule force-induced unfolding experiments by a high-resolution optical tweezers on a DNA telomeric sequence capable of adopting a G-quadruplex conformation. Fitting the parameters of the model to the experiments we find a correct prediction of the rupture-force kinetics and a good agreement with previous near equilibrium measurements. Since G-quadruplex unfolding dynamics is halfway in complexity between secondary nucleic acids and tertiary protein structures, our model entails a nanoscale paradigm for non-equilibrium processes in the cell.Work supported by the Spanish Ministry of Economy and Competitiveness (MINECO), grant No. FIS2014-55867, co-financed by FEDER funds. We also thank the support of the Aragon Government and Fondo Social Europeo to FENOL group. Work in J.R.A.-G. laboratory was supported by a grant from MINECO, No. MAT2015-71806-R).Bergues-Pupo, A.; Gutiérrez, I.; Arias-Gonzalez, JR.; Falo, F.; Fiasconaro, A. (2017). Mesoscopic model for DNA G-quadruplex unfolding. Scientific Reports. 7:1-13. https://doi.org/10.1038/s41598-017-10849-2S1137Arias-Gonzalez, J. R. Single-molecule portrait of DNA and RNA double helices. Integr. 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Single-molecule study of G-quadruplex disruption using dynamic force spectroscopy. Phys. Rev. Lett. 109, 058101 (2012).Koirala, D. et al. A single-molecule platform for investigation of interactions between G-quadruplexes and small-molecule ligands. Nat. Chem. 3, 782 (2011).Long, X. et al. Mechanical unfolding of human telomere G-quadruplex DNA probed by integrated fluorescence and magnetic tweezers spectroscopy. Nucleic Acids Res. 41, 2746 (2013).Ghimire, C. et al. Direct Quantification of Loop Interaction and pi-pi Stacking for G-Quadruplex Stability at the Submolecular Level. J. Am. Chem. Soc. 136, 15544 (2014).Garavís, M. et al. Mechanical Unfolding of Long Human Telomeric RNA (TERRA). Chem. Commun. 49, 6397 (2013).Fonseca Guerra, C., Zijlstra, H., Paragi, G. & Bickelhaupt, F. M. Telomere structure and stability: covalency in hydrogen bonds, not resonance assistance, causes cooperativity in guanine quartets. Chemistry-A European Journal 17, 12612 (2011).Yurenko, Y. P., Novotn, J., Sklen, V. & Marek, R. Exploring non-covalent interactions in guanine-and xanthine-based model DNA quadruplex structures: a comprehensive quantum chemical approach. Phys. Chem. Chem. Phys. 16, 2072 (2014).Poudel, L. et al. Implication of the solvent effect, metal ions and topology in the electronic structure and hydrogen bonding of human telomeric G-quadruplex DNA. Phys. Chem. Chem. Phys. 18, 21573 (2016).Li, M. H., Luo, Q., Xue, X. G. & Li, Z. S. Toward a full structural characterization of G-quadruplex DNA in aqueous solution: Molecular dynamics simulations of four G-quadruplex molecules. J. Mol. Struct-Theochem. 952, 96 (2010).Islam, B. et al. Conformational dynamics of the human propeller telomeric DNA quadruplex on a microsecond time scale. Nucleic Acids Res. 41, 2723 (2013).Stadlbauer, P., Krepl, M., Cheatham, T. E., Koca, J. & Sponer, J. Structural dynamics of possible late-stage intermediates in folding of quadruplex DNA studied by molecular simulations. Nucleic Acids Res. 41, 7128 (2013).Li, H., Cao, E. & Gisler, T. Force-induced unfolding of human telomeric G-quadruplex: a steered molecular dynamics simulation study. Biochem. Bioph. Res. Co. 379, 70 (2009).Yang, C., Jang, S. & Pak, Y. Multiple stepwise pattern for potential of mean force in unfolding the thrombin binding aptamer in complex with Sr2+. J. Chem. Phys. 135, 225104 (2011).Bergues-Pupo, A. E., Arias-Gonzalez, J. R., Morón, M. C., Fiasconaro, A. & Falo, F. Role of the central cations in the mechanical unfolding of DNA and RNA G-quadruplexes. Nucleic Acids Res. 43, 7638 (2015).Linak, M. C., Tourdot, R. & Dorfman, K. D. Moving beyond Watson-Crick models of coarse grained DNA dynamics. J. Chem Phys. 135, 205102 (2011).Rebi, M., Mocci, F., Laaksonen, A. & Ulin, J. Multiscale simulations of human telomeric G-quadruplex DNA. J. Phys. Chem. B 119, 105 (2014).Stadlbauer, P. et al. Coarse-Grained Simulations Complemented by Atomistic Molecular Dynamics Provide New Insights into Folding and Unfolding of Human Telomeric G-Quadruplexes. J. Chem. Theory Comput. 12, 6077 (2016).Parkinson, G. N., Lee, M. P. & Neidle, S. Crystal structure of parallel quadruplexes from human telomeric DNA. Nature 417, 876 (2002).Bhattacharya, D., Arachchilageand, G. M. & Basu, S. Metal Cations in G-Quadruplex Folding and Stability. Frontiers in Chemistry 4, 38 (2016).de Lorenzo, S., Ribezzi-Crivellari, M., Arias-Gonzalez, J. R., Smith, S. B. & Ritort, F. A Temperature-Jump Optical Trap for Single-Molecule Manipulation. Biophys. J. 108, 2854 (2015).Smith, S. B., Cui, Y. & Bustamante, C. Optical-trap force transducer that operates by direct measurement of light momentum. Methods Enzymol. 361, 134 (2003).Mergny, J. L., Phan, A. T. & Lacroix, L. Following G-quartet formation by UV-spectroscopy. FEBS letters 435, 74 (1998).Torrie, G. M. & Valleau, J. P. 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From evolutionary computation to the evolution of things

Evolution has provided a source of inspiration for algorithm designers since the birth of computers. The resulting field, evolutionary computation, has been successful in solving engineering tasks ranging in outlook from the molecular to the astronomical. Today, the field is entering a new phase as evolutionary algorithms that take place in hardware are developed, opening up new avenues towards autonomous machines that can adapt to their environment. We discuss how evolutionary computation compares with natural evolution and what its benefits are relative to other computing approaches, and we introduce the emerging area of artificial evolution in physical systems

Population mechanics: A mathematical framework to study T cell homeostasis

Unlike other cell types, T cells do not form spatially arranged tissues, but move independently throughout the body. Accordingly, the number of T cells in the organism does not depend on physical constraints imposed by the shape or size of specific organs. Instead, it is determined by competition for interleukins. From the perspective of classical population dynamics, competition for resources seems to be at odds with the observed high clone diversity, leading to the so-called diversity paradox. In this work we make use of population mechanics, a non-standard theoretical approach to T cell homeostasis that accounts for clone diversity as arising from competition for interleukins. The proposed models show that carrying capacities of T cell populations naturally emerge from the balance between interleukins production and consumption. These models also suggest remarkable functional differences in the maintenance of diversity in naïve and memory pools. In particular, the distribution of memory clones would be biased towards clones activated more recently, or responding to more aggressive pathogenic threats. In contrast, permanence of naïve T cell clones would be determined by their affinity for cognate antigens. From this viewpoint, positive and negative selection can be understood as mechanisms to maximize naïve T cell diversity

Conserved Mosquito/Parasite Interactions Affect Development of Plasmodium falciparum in Africa

In much of sub-Saharan Africa, the mosquito Anopheles gambiae is the main vector of the major human malaria parasite, Plasmodium falciparum. Convenient laboratory studies have identified mosquito genes that affect positively or negatively the developmental cycle of the model rodent parasite, P. berghei. Here, we use transcription profiling and reverse genetics to explore whether five disparate mosquito gene regulators of P. berghei development are also pertinent to A. gambiae/P. falciparum interactions in semi-natural conditions, using field isolates of this parasite and geographically related mosquitoes. We detected broadly similar albeit not identical transcriptional responses of these genes to the two parasite species. Gene silencing established that two genes affect similarly both parasites: infections are hindered by the intracellular local activator of actin cytoskeleton dynamics, WASP, but promoted by the hemolymph lipid transporter, ApoII/I. Since P. berghei is not a natural parasite of A. gambiae, these data suggest that the effects of these genes have not been drastically altered by constant interaction and co-evolution of A. gambiae and P. falciparum; this conclusion allowed us to investigate further the mode of action of these two genes in the laboratory model system using a suite of genetic tools and infection assays. We showed that both genes act at the level of midgut invasion during the parasite's developmental transition from ookinete to oocyst. ApoII/I also affects the early stages of oocyst development. These are the first mosquito genes whose significant effects on P. falciparum field isolates have been established by direct experimentation. Importantly, they validate for semi-field human malaria transmission the concept of parasite antagonists and agonists

Large-Scale Absence of Sharks on Reefs in the Greater-Caribbean: A Footprint of Human Pressures

BACKGROUND: In recent decades, large pelagic and coastal shark populations have declined dramatically with increased fishing; however, the status of sharks in other systems such as coral reefs remains largely unassessed despite a long history of exploitation. Here we explore the contemporary distribution and sighting frequency of sharks on reefs in the greater-Caribbean and assess the possible role of human pressures on observed patterns. METHODOLOGY/PRINCIPAL FINDINGS: We analyzed 76,340 underwater surveys carried out by trained volunteer divers between 1993 and 2008. Surveys were grouped within one km2 cells, which allowed us to determine the contemporary geographical distribution and sighting frequency of sharks. Sighting frequency was calculated as the ratio of surveys with sharks to the total number of surveys in each cell. We compared sighting frequency to the number of people in the cell vicinity and used population viability analyses to assess the effects of exploitation on population trends. Sharks, with the exception of nurse sharks occurred mainly in areas with very low human population or strong fishing regulations and marine conservation. Population viability analysis suggests that exploitation alone could explain the large-scale absence; however, this pattern is likely to be exacerbated by additional anthropogenic stressors, such as pollution and habitat degradation, that also correlate with human population. CONCLUSIONS/SIGNIFICANCE: Human pressures in coastal zones have lead to the broad-scale absence of sharks on reefs in the greater-Caribbean. Preventing further loss of sharks requires urgent management measures to curb fishing mortality and to mitigate other anthropogenic stressors to protect sites where sharks still exist. The fact that sharks still occur in some densely populated areas where strong fishing regulations are in place indicates the possibility of success and encourages the implementation of conservation measures

Laparoscopy in management of appendicitis in high-, middle-, and low-income countries: a multicenter, prospective, cohort study.

BACKGROUND: Appendicitis is the most common abdominal surgical emergency worldwide. Differences between high- and low-income settings in the availability of laparoscopic appendectomy, alternative management choices, and outcomes are poorly described. The aim was to identify variation in surgical management and outcomes of appendicitis within low-, middle-, and high-Human Development Index (HDI) countries worldwide. METHODS: This is a multicenter, international prospective cohort study. Consecutive sampling of patients undergoing emergency appendectomy over 6 months was conducted. Follow-up lasted 30 days. RESULTS: 4546 patients from 52 countries underwent appendectomy (2499 high-, 1540 middle-, and 507 low-HDI groups). Surgical site infection (SSI) rates were higher in low-HDI (OR 2.57, 95% CI 1.33-4.99, p = 0.005) but not middle-HDI countries (OR 1.38, 95% CI 0.76-2.52, p = 0.291), compared with high-HDI countries after adjustment. A laparoscopic approach was common in high-HDI countries (1693/2499, 67.7%), but infrequent in low-HDI (41/507, 8.1%) and middle-HDI (132/1540, 8.6%) groups. After accounting for case-mix, laparoscopy was still associated with fewer overall complications (OR 0.55, 95% CI 0.42-0.71, p < 0.001) and SSIs (OR 0.22, 95% CI 0.14-0.33, p < 0.001). In propensity-score matched groups within low-/middle-HDI countries, laparoscopy was still associated with fewer overall complications (OR 0.23 95% CI 0.11-0.44) and SSI (OR 0.21 95% CI 0.09-0.45). CONCLUSION: A laparoscopic approach is associated with better outcomes and availability appears to differ by country HDI. Despite the profound clinical, operational, and financial barriers to its widespread introduction, laparoscopy could significantly improve outcomes for patients in low-resource environments. TRIAL REGISTRATION: NCT02179112

A922 Sequential measurement of 1 hour creatinine clearance (1-CRCL) in critically ill patients at risk of acute kidney injury (AKI)

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