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https://www.readbyqxmd.com/read/28941402/copper-ii-ions-interactions-in-the-systems-with-triamines-and-atp-potentiometric-and-spectroscopic-studies
#1
S K Hoffmann, J Goslar, R Bregier-Jarzebowska, A Gasowska, A Zalewska, L Lomozik
The mode of interaction and thermodynamic stability of complexes formed in binary and ternary Cu(II)/ATP/triamines systems were studied using potentiometric and spectroscopic (NMR, EPR, UV-Vis) methods. It was found that in binary metal-free systems ATP/HxPA species are formed (PA: Spd=spermidine or 3,3-tri=1,7-diamino-4-azaheptane) where the phosphate groups from nucleotides are preferred negative centers and protonated amine groups of amines are positive centers of reaction. In the ternary systems Cu/ATP/Hx(PA) as well as Cu/(ATP)(PA) species are formed...
September 9, 2017: Journal of Inorganic Biochemistry
https://www.readbyqxmd.com/read/28938749/the-testicular-transcriptome-associated-with-spermatogonia-differentiation-initiated-by-gonadotrophin-stimulation-in-the-juvenile-rhesus-monkey-macaca-mulatta
#2
Suresh Ramaswamy, William H Walker, Paula Aliberti, Rahil Sethi, Gary R Marshall, Alyxzandria Smith, Seyedmehdi Nourashrafeddin, Alicia Belgorosky, Uma R Chandran, Mark P Hedger, Tony M Plant
STUDY QUESTION: What is the genetic landscape within the testis of the juvenile rhesus monkey (Macaca mulatta) that underlies the decision of undifferentiated spermatogonia to commit to a pathway of differentiation when puberty is induced prematurely by exogenous LH and FSH stimulation? SUMMARY ANSWER: Forty-eight hours of gonadotrophin stimulation of the juvenile monkey testis resulted in the appearance of differentiating B spermatogonia and the emergence of 1362 up-regulated and 225 down-regulated testicular mRNAs encoding a complex network of proteins ranging from enzymes regulating Leydig cell steroidogenesis to membrane receptors, and from juxtacrine and paracrine factors to transcriptional factors governing spermatogonial stem cell fate...
October 1, 2017: Human Reproduction
https://www.readbyqxmd.com/read/28938744/an-improved-ivm-method-for-cumulus-oocyte-complexes-from-small-follicles-in-polycystic-ovary-syndrome-patients-enhances-oocyte-competence-and-embryo-yield
#3
F Sánchez, F Lolicato, S Romero, M De Vos, H Van Ranst, G Verheyen, E Anckaert, J E J Smitz
STUDY QUESTION: Are meiotic and developmental competence of human oocytes from small (2-8 mm) antral follicles improved by applying an optimized IVM method involving a prematuration step in presence of C-Type Natriuretic Peptide (CNP) followed by a maturation step in presence of FSH and Amphiregulin (AREG)? SUMMARY ANSWER: A strategy involving prematuration culture (PMC) in the presence of CNP followed by IVM using FSH + AREG increases oocyte maturation potential leading to a higher availability of Day 3 embryos and good-quality blastocysts for single embryo transfer...
October 1, 2017: Human Reproduction
https://www.readbyqxmd.com/read/28938461/adipokines-and-their-receptor-are-widely-expressed-and-distinctly-regulated-by-the-metabolic-environment-in-the-prostate-of-male-mice-direct-role-under-normal-and-tumoral-conditions
#4
André Sarmento-Cabral, Fernando L-López, Raúl M Luque
Adipose tissue-derived adipokines (i.e. leptin/adiponectin/resistin) play important roles in the regulation of several pathophysiological processes through the activation of specific receptors. However, although adipokines and their receptors are widely distributed in many tissues and exhibit a clear modulation by the particular metabolic conditions (e.g. obesity and/or fasting), their expression, regulation, and putative action on normal prostate-glands (PGs; a hormone-dependent organ tightly regulated by the endocrine-metabolic milieu) is still to be defined...
August 9, 2017: Endocrinology
https://www.readbyqxmd.com/read/28938418/androgens-support-male-acrobatic-courtship-behavior-by-enhancing-muscle-speed-and-easing-the-severity-of-its-trade-off-with-force
#5
Matthew J Fuxjager, Meredith C Miles, Franz Goller, John Petersen, Julia Yancey
Steroid hormone action in the brain regulates many animals' elaborate social displays used for courtship and competition, but it is increasingly recognized that the periphery may also be a site for potent steroidal modulation of complex behavior. However, the mechanisms of such "bottom up" regulation of behavioral outflow are largely unclear. To study this problem, we examine how androgenic sex hormones act through the skeletal muscular system to mediate elaborate courtship acrobatics in a tropical bird called the golden-collared manakin...
August 29, 2017: Endocrinology
https://www.readbyqxmd.com/read/28938251/critical-illness-related-corticosteroid-insufficiency-circi-a-narrative-review-from-a-multispecialty-task-force-of-the-society-of-critical-care-medicine-sccm-and-the-european-society-of-intensive-care-medicine-esicm
#6
Djillali Annane, Stephen M Pastores, Wiebke Arlt, Robert A Balk, Albertus Beishuizen, Josef Briegel, Joseph Carcillo, Mirjam Christ-Crain, Mark S Cooper, Paul E Marik, Gianfranco Umberto Meduri, Keith M Olsen, Bram Rochwerg, Sophia C Rodgers, James A Russell, Greet Van den Berghe
OBJECTIVE: To provide a narrative review of the latest concepts and understanding of the pathophysiology of critical illness-related corticosteroid insufficiency (CIRCI). PARTICIPANTS: A multi-specialty task force of international experts in critical care medicine and endocrinology and members of the Society of Critical Care Medicine and the European Society of Intensive Care Medicine. DATA SOURCES: Medline, Database of Abstracts of Reviews of Effects (DARE), Cochrane Central Register of Controlled Trials (CENTRAL) and the Cochrane Database of Systematic Reviews...
September 21, 2017: Critical Care Medicine
https://www.readbyqxmd.com/read/28938250/listening-effort-how-the-cognitive-consequences-of-acoustic-challenge-are-reflected-in-brain-and-behavior
#7
Jonathan E Peelle
Everyday conversation frequently includes challenges to the clarity of the acoustic speech signal, including hearing impairment, background noise, and foreign accents. Although an obvious problem is the increased risk of making word identification errors, extracting meaning from a degraded acoustic signal is also cognitively demanding, which contributes to increased listening effort. The concepts of cognitive demand and listening effort are critical in understanding the challenges listeners face in comprehension, which are not fully predicted by audiometric measures...
September 21, 2017: Ear and Hearing
https://www.readbyqxmd.com/read/28938212/the-problem-of-identifying-arsenic-anomalies-in-the-basin-of-sahand-dam-through-risk-based-soft-modelling
#8
Ata Allah Nadiri, Fariba Sadeghi Aghdam, Rahman Khatibi, Asghar Asghari Moghaddam
An investigation is undertaken to identify arsenic anomalies at the complex of Sahand dam, East Azerbaijan, northwest Iran. The complex acts as a system, in which the impounding reservoir catalyses system components related to Origin-Source-Pathways-Receptor-Consequence (OSPRC) viewed as a risk system. This 'conceptual framework' overlays a 'perceptual model' of the physical system, in which arsenic with geogenic origins diffused into the formations through extensive fractures swept through the region during the Miocene era...
September 19, 2017: Science of the Total Environment
https://www.readbyqxmd.com/read/28938199/determination-of-lead-at-trace-levels-in-mussel-and-sea-water-samples-using-vortex-assisted-dispersive-liquid-liquid-microextraction-slotted-quartz-tube-flame-atomic-absorption-spectrometry
#9
Sezin Erarpat, Gözde Özzeybek, Dotse Selali Chormey, Sezgin Bakırdere
In this study, dispersive liquid-liquid microextraction (DLLME) and slotted quartz tube (SQT) were coupled to flame atomic absorption spectrometry (FAAS) to increase the sensitivity of lead. Conditions such as the formation of the lead-dithizone complex, efficiency of the DLLME method and the output of the SQT were systematically optimized to improve the detection limit for the analyte. The conventional FAAS system was improved upon by about 3.0 times with SQT-FAAS, 32 times with DLLME-FAAS and 142 times with DLLME-SQT-FAAS...
September 17, 2017: Chemosphere
https://www.readbyqxmd.com/read/28938196/sorption-of-uranium-vi-onto-hydrous-ferric-oxide-modified-zeolite-assessment-of-the-effect-of-ph-contact-time-temperature-selected-cations-and-anions-on-sorbent-interactions
#10
Pfano Mathews Nekhunguni, Nikita Tawanda Tavengwa, Hlanganani Tutu
Zeolites are commonly used as adsorbents for metal removal in most applications e.g. in wastewater. However, the ubiquity of iron in such systems may, in the long-term, distort the true interactions and mechanisms of contaminant removal as a result of modification of the zeolite surface. In this study, this potential phenomenon was assessed for the removal of uranium(VI) from aqueous solution by hydrous ferric oxide-modified zeolite (HFOMZ). This was prepared by precipitating iron hydroxide (the common precipitate of iron in aqueous systems) onto zeolite...
September 19, 2017: Journal of Environmental Management
https://www.readbyqxmd.com/read/28938124/the-kinetochore-receptor-for-the-cohesin-loading-complex
#11
Stephen M Hinshaw, Vasso Makrantoni, Stephen C Harrison, Adèle L Marston
The ring-shaped cohesin complex brings together distant DNA domains to maintain, express, and segregate the genome. Establishing specific chromosomal linkages depends on cohesin recruitment to defined loci. One such locus is the budding yeast centromere, which is a paradigm for targeted cohesin loading. The kinetochore, a multiprotein complex that connects centromeres to microtubules, drives the recruitment of high levels of cohesin to link sister chromatids together. We have exploited this system to determine the mechanism of specific cohesin recruitment...
September 21, 2017: Cell
https://www.readbyqxmd.com/read/28938122/genome-regulation-by-polycomb-and-trithorax-70-years-and-counting
#12
REVIEW
Bernd Schuettengruber, Henri-Marc Bourbon, Luciano Di Croce, Giacomo Cavalli
Polycomb (PcG) and Trithorax (TrxG) group proteins are evolutionarily conserved chromatin-modifying factors originally identified as part of an epigenetic cellular memory system that maintains repressed or active gene expression states. Recently, they have been shown to globally control a plethora of cellular processes. This functional diversity is achieved by their ability to regulate chromatin at multiple levels, ranging from modifying local chromatin structure to orchestrating the three-dimensional organization of the genome...
September 21, 2017: Cell
https://www.readbyqxmd.com/read/28938009/altering-neuronal-excitability-to-preserve-network-connectivity-in-a-computational-model-of-alzheimer-s-disease
#13
Willem de Haan, Elisabeth C W van Straaten, Alida A Gouw, Cornelis J Stam
Neuronal hyperactivity and hyperexcitability of the cerebral cortex and hippocampal region is an increasingly observed phenomenon in preclinical Alzheimer's disease (AD). In later stages, oscillatory slowing and loss of functional connectivity are ubiquitous. Recent evidence suggests that neuronal dynamics have a prominent role in AD pathophysiology, making it a potentially interesting therapeutic target. However, although neuronal activity can be manipulated by various (non-)pharmacological means, intervening in a highly integrated system that depends on complex dynamics can produce counterintuitive and adverse effects...
September 22, 2017: PLoS Computational Biology
https://www.readbyqxmd.com/read/28937984/evidence-of-complex-contagion-of-information-in-social-media-an-experiment-using-twitter-bots
#14
Bjarke Mønsted, Piotr Sapieżyński, Emilio Ferrara, Sune Lehmann
It has recently become possible to study the dynamics of information diffusion in techno-social systems at scale, due to the emergence of online platforms, such as Twitter, with millions of users. One question that systematically recurs is whether information spreads according to simple or complex dynamics: does each exposure to a piece of information have an independent probability of a user adopting it (simple contagion), or does this probability depend instead on the number of sources of exposure, increasing above some threshold (complex contagion)? Most studies to date are observational and, therefore, unable to disentangle the effects of confounding factors such as social reinforcement, homophily, limited attention, or network community structure...
2017: PloS One
https://www.readbyqxmd.com/read/28937978/a-new-discrete-dynamic-model-of-aba-induced-stomatal-closure-predicts-key-feedback-loops
#15
Réka Albert, Biswa R Acharya, Byeong Wook Jeon, Jorge G T Zañudo, Mengmeng Zhu, Karim Osman, Sarah M Assmann
Stomata, microscopic pores in leaf surfaces through which water loss and carbon dioxide uptake occur, are closed in response to drought by the phytohormone abscisic acid (ABA). This process is vital for drought tolerance and has been the topic of extensive experimental investigation in the last decades. Although a core signaling chain has been elucidated consisting of ABA binding to receptors, which alleviates negative regulation by protein phosphatases 2C (PP2Cs) of the protein kinase OPEN STOMATA 1 (OST1) and ultimately results in activation of anion channels, osmotic water loss, and stomatal closure, over 70 additional components have been identified, yet their relationships with each other and the core components are poorly elucidated...
September 22, 2017: PLoS Biology
https://www.readbyqxmd.com/read/28937963/ki67-and-lymphocytes-in-the-pretherapeutic-core-biopsy-of-primary-invasive-breast-cancer-positive-markers-of-therapy-response-prediction-and-superior-survival
#16
REVIEW
Claus M Schlotter, Lothar Tietze, Ulf Vogt, Carlos Villena Heinsen, Antje Hahn
Background Core needle biopsy plays a crucial role as diagnostic tool for BC. Both Ki67 and likely tumor-infiltrating lymphocytes (TILs) in the near future are determining the kind of systemic therapy. The role of TILs in BC is still an issue for clinical research, albeit preliminary results of neoadjuvant and adjuvant clinical studies already now highlight the crucial impact of TILs on therapy response and survival. Methods Evaluation of related publications (pubmed) and meeting abstracts (ASCO, SABCS). Results The monoclonal antibody Ki67 recognizing a nuclear antigene in proliferating cells is a positive marker of therapy response and superior survival...
September 22, 2017: Hormone Molecular Biology and Clinical Investigation
https://www.readbyqxmd.com/read/28937949/international-vision-care-issues-and-approaches
#17
Rohit C Khanna, Srinivas Marmamula, Gullapalli N Rao
Globally, 32.4 million individuals are blind and 191 million have moderate or severe visual impairment (MSVI); 80% of cases of blindness and MSVI are avoidable. However, great efforts are needed to tackle blindness and MSVI, as eye care in most places is delivered in isolation from and without significant integration with general health sectors. Success stories, including control of vitamin A deficiency, onchocerciasis, and trachoma, showed that global partnerships, multisectoral collaboration, public-private partnerships, corporate philanthropy, support from nongovernmental organizations-both local and international-and governments are responsible for the success of these programs...
September 15, 2017: Annual Review of Vision Science
https://www.readbyqxmd.com/read/28937829/nonlinearity-coherence-and-complexity-biophysical-aspects-related-to-health-and-disease
#18
Alberto Foletti, Larissa Brizhik
Biological organisms are complex open dissipative systems whose dynamical stability is sustained due to the exchange of matter, energy and information. Dynamical stability occurs through a number of mechanisms that sustain efficient adaptive dynamics. Such properties of living matter can be the consequence of a self-consistent state of matter and electromagnetic field (EMF). Based on the soliton model of charge transport in redox processes, we describe a possible mechanism of the origin of endogenous EMF and coherence...
September 22, 2017: Electromagnetic Biology and Medicine
https://www.readbyqxmd.com/read/28937744/methane-c-h-activation-via-3d-metal-methoxide-complexes-with-potentially-redox-noninnocent-pincer-ligands-a-density-functional-theory-study
#19
Ahmad Najafian, Thomas R Cundari
This paper reports a density functional theory study of 3d transition-metal methoxide complexes with potentially redox-noninnocent pincer supporting ligands for methane C-H bond activation to form methanol (LnM-OMe + CH4 → LnM-Me + CH3OH). The three types of tridentate pincer ligands [terpyridine (NNN), bis(2-pyridyl)phenyl-C,N,N' (NCN), and 2,6-bis(2-phenyl)pyridine-N,C,C' (CNC)] and different first-row transition metals (M = Ti, V, Cr, Mn, Fe, Co, Ni, and Cu) are used to elucidate the reaction mechanism as well as the effect of the metal identity on the thermodynamics and kinetics of a methane activation reaction...
September 22, 2017: Inorganic Chemistry
https://www.readbyqxmd.com/read/28937734/discovery-of-oligonucleotide-signaling-mediated-by-crispr-associated-polymerases-solves-two-puzzles-but-leaves-an-enigma
#20
Eugene V Koonin, Kira S Makarova
The signature component of type III CRISPR-Cas systems is the Cas10 protein that consists of two Palm domains homologous to those of DNA and RNA polymerases, and nucleotide cyclases, and an HD nuclease domain. However, until very recently, the activity of the Palm domains and their role in CRISPR function have not been experimentally established. Most of the type III CRISPR-Cas systems and some type I systems also encompass proteins containing the CARF (CRISPR-associated Rossmann fold) domain that has been predicted to regulate CRISPR functions via nucleotide binding but its function in CRISPR-Cas remained obscure...
September 22, 2017: ACS Chemical Biology
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