Frequency Of Exchanges Research Articles

Antioxidant and Genotoxic Properties of Hispidin Isolated from the Velvet-Top Mushroom, Phaeolus schweinitzii (Agaricomycetes).

Antioxidant and genotoxic properties of hispidin isolated from the Phaeolus schweinitzii mushroom were evaluated with various assays. Hispidin demonstrated strong free radical scavenging, oxygen radical absorbance capacity, and ferric-reducing antioxidant power; in all applied assays, hispidin exhibited antioxidant capacity similar to or higher than that of the reference antioxidant Trolox. Genotoxic activity of hispidin was assessed using different end points: chromosome aberrations, micronuclei, sister chromatid exchanges, and primary DNA damage (detected by the comet assay) in human lymphocytes in vitro, and gene mutations in the Salmonella/microsome test. Hispidin did not increase the frequency of chromosome aberrations, micronuclei, or primary DNA damage in human lymphocytes in vitro and did not produce reverse mutation in bacterial cells. However, we identified in human lymphocytes a statistically significant dose-dependent increase in sister chromatid exchange frequency and a decrease in replication index and nuclear division index values.

In vitro Effects of Epigallocatechin Gallate on Sister Chromatid Exchange in the Lymphocytes Exposed to Glyphosate

Purpose: Green tea is known as a potent anti-oxidant, anti-carcinogen, and genetic protector. Glyphosate (N-phosphonomethyl glycine) is a widely used non-selective herbicide that causes DNA damage. The present study was conducted to investigate the protective effects of green tea in human blood lymphocytes exposed to glyphosate using the Sister Chromatid Exchange (SCE) frequency method. Methods: Peripheral blood was obtained from 10 volunteers and cultured through four different conditions. Four groups were divided into control, glyphosate only (300 ng/mL), glyphosate and low ($20{mu}m$) concentrations of epigallocatechin gallate (EGCG) and glyphosate and high ($100{mu}m$) concentrations of EGCG. Results: The glyphosate exposed groups had a higher mean SCE frequency ($10.33{pm}2.50$) than the control group ($6.38{pm}2.28$, p<0.001). The low concentrations of EGCG groups had a lower mean SCE frequency ($9.91{pm}1.93$) than the glyphosate-only group, although this difference was not significant (p=0.219). However, the high concentration group ($9.49{pm}1.85$) had a significantly lower SCE frequency than the glyphosate-only group (p=0.001). Conclusion: EGCG has a gene protective effect in human lymphocytes exposed to the genotoxicity of glyphosate in the case of high concentrations.

Genoprotective Effect of Melatonin Against to the Genotoxicity of Glyphosate on Human Blood Lymphocytes

Purpose: Glyphosate is a widely used non-selective herbicide. Previous studies have shown that glyphosate has genotoxicity, and that even low-doses of glyphosate can cause DNA damage. Melatonin is a hormone produced and secreted by the pineal gland that is known to be a potent anti-carcinogen, anti-oxidant, and genetic protector. This study was conducted to investigate the genoprotective effect of melatonin against glyphosate in human blood lymphocytes. Methods: Human peripheral blood was obtained from 15 young, healthy volunteers and cultured under four different toxicologic conditions. The four groups consisted of a control group, glyphosate only group (300 ng/mL), glyphosate with low level of melatonin group ($50{mu}M$), and glyphosate with high level of melatonin group ($200{mu}M$). The mean Sister Chromatid Exchange (SCE) frequency of each group was then analyzed. Results: Glyphosate exposed groups had a higher mean SCE frequency ($10.33{pm}2.50$) than the control group ($6.78{pm}2.31$, p<0.001). Interestingly, the group that received a low-level of melatonin had a lower mean SCE frequency ($8.67{pm}2.58$) than the glyphosate-only group, while the group that received a high level of melatonin had a much lower mean SCE frequency ($8.06{pm}2.50$) than the glyphosate-only group. There was statistical significance. Conclusion: Melatonin exerted a potent gene protective effect against the genotoxicity of glyphosate on human blood lymphocytes in a dose-dependent fashion.

Gene Turnover Contributes to the Evolutionary Adaptation of Acidithiobacillus caldus: Insights from Comparative Genomics.

Acidithiobacillus caldus is an extremely acidophilic sulfur-oxidizer with specialized characteristics, such as tolerance to low pH and heavy metal resistance. To gain novel insights into its genetic complexity, we chosen six A. caldus strains for comparative survey. All strains analyzed in this study differ in geographic origins as well as in ecological preferences. Based on phylogenomic analysis, we clustered the six A. caldus strains isolated from various ecological niches into two groups: group 1 strains with smaller genomes and group 2 strains with larger genomes. We found no obvious intraspecific divergence with respect to predicted genes that are related to central metabolism and stress management strategies between these two groups. Although numerous highly homogeneous genes were observed, high genetic diversity was also detected. Preliminary inspection provided a first glimpse of the potential correlation between intraspecific diversity at the genome level and environmental variation, especially geochemical conditions. Evolutionary genetic analyses further showed evidence that the difference in environmental conditions might be a crucial factor to drive the divergent evolution of A. caldus species. We identified a diverse pool of mobile genetic elements including insertion sequences and genomic islands, which suggests a high frequency of genetic exchange in these harsh habitats. Comprehensive analysis revealed that gene gains and losses were both dominant evolutionary forces that directed the genomic diversification of A. caldus species. For instance, horizontal gene transfer and gene duplication events in group 2 strains might contribute to an increase in microbial DNA content and novel functions. Moreover, genomes undergo extensive changes in group 1 strains such as removal of potential non-functional DNA, which results in the formation of compact and streamlined genomes. Taken together, the findings presented herein show highly frequent gene turnover of A. caldus species that inhabit extremely acidic environments, and shed new light on the contribution of gene turnover to the evolutionary adaptation of acidophiles.

African and classical swine fever situation in Ivory-Coast and neighboring countries, 2008–2013

This study was conducted from 2008 to 2013 to determine the animal health status of Ivory Coast and neighboring countries (Burkina Faso, Ghana, Togo and Benin) for African swine fever (ASF) and classical swine fever (CSF), and to assess the risk factors for ASF introduction in Ivory Coast. Ivory Coast had probably been free from ASF from 1998 to 2014 when it was re-introduced in this country. However, the ASF virus was found in all neighboring countries. In contrast, no evidence of CSF infection was found so far in Ivory Coast and neighboring countries. To assess the risk of ASF reintroduction in Ivory Coast, we surveyed 59 modern pig farms, and 169 pig owners in 19 villages and in two towns. For the village livestock, the major risk factor was the high frequency of pig exchanges with Burkinabe villages. In the commercial sector, many inadequate management practices were observed with respect to ASF. Their identification should enable farmers and other stakeholders to implement a training and prevention program to reduce the introduction risk of ASF in their farms.

The Detection of Prominent Hardware in Volar Locked Plating of Distal Radius Fractures: Intraoperative Fluoroscopy Versus Computed Tomography

To assess the utility of the dorsal tangential view (DTV) in detecting intraoperative dorsal screw penetration in distal radius fractures treated with volar locked plating. Retrospective cohort study. Academic level 1 trauma center. Skeletally mature patients where open reduction internal fixation with volar locked plating was the definitive treatment. A total of twenty-six patients were evaluated. Intraoperative anteroposterior, lateral, 20 degree tilted lateral, and DTVs were obtained through fluoroscopy in all wrists. Screw exchange and position by fluoroscopic view was recorded. A computed tomography (CT) was taken postoperatively to identify residual prominent screws. Data points included frequency of screw exchange by standard fluoroscopic views, the DTV, and residual prominent screws detected by CT. Eight constructs of thirty (27%) had prominent screws evident on the DTV but not seen on standard fluoroscopic analysis. CT identified 5 additional screws with ≥1 mm dorsal penetration not identified by the DTV. All except 1 screw was in the second dorsal wrist compartment. The DTV was 67% sensitive with a negative predictive value of 97%. It is risky and unnecessary to place bicortical screws in the distal part of a volar plate. Given that the DTV view was not sufficient to avoid dorsal screw prominence, distal screws should be intentionally 2-4 mm shorter than measured. Recent studies propose bicortical distal locking screws are not needed for sufficient construct stiffness in volar locked plating. We suggest caution when using this view to verify acceptable placement of screws in proximity to the second dorsal compartment. Diagnostic level III. See Instructions for Authors for a complete description of levels of evidence.

Genotoxicity of Casiopeina III-Ea in mouse bone marrow cells

Casiopeina III-Ea® (Cas III-Ea®) is a chelated copper complex with antineoplastic activity that is capable of reducing tumor size and inducing antiproliferative and apoptotic effects. However, little is known about its in vivo genotoxic effects. Therefore, this study evaluated two cytogenetic and two proliferative parameters 24 h after the administration of Casiopeina III-Ea® to male CD-1 mice. Three doses of Cas III-Ea® were administered by intraperitoneal injections of 1.69, 3.39 and 6.76 mg/kg (corresponding to 1/8, 1/4 and 1/2 of LD50, respectively). A reduction in the mitotic index (MI) and an increased numbers of cells with structural chromosomal aberrations (SCA) were detected. Additionally, a low but significant increase in the frequency of sister chromatid exchange (SCE) was observed at the highest dose. Changes in the DNA replication index (RI) were not observed. These results indicate that Casiopeina III-Ea® shows cytotoxic and clastogenic activity in bone marrow cells from treated mice.

Mobility, Modernity, and Abroad

Mobility, Modernity, and Abroad

Coherent spin-exchange via a quantum mediator.

Coherent interactions at a distance provide a powerful tool for quantum simulation and computation. The most common approach to realize an effective long-distance coupling 'on-chip' is to use a quantum mediator, as has been demonstrated for superconducting qubits and trapped ions. For quantum dot arrays, which combine a high degree of tunability with extremely long coherence times, the experimental demonstration of the time evolution of coherent spin-spin coupling via an intermediary system remains an important outstanding goal. Here, we use a linear triple-quantum-dot array to demonstrate a coherent time evolution of two interacting distant spins via a quantum mediator. The two outer dots are occupied with a single electron spin each, and the spins experience a superexchange interaction through the empty middle dot, which acts as mediator. Using single-shot spin readout, we measure the coherent time evolution of the spin states on the outer dots and observe a characteristic dependence of the exchange frequency as a function of the detuning between the middle and outer dots. This approach may provide a new route for scaling up spin qubit circuits using quantum dots, and aid in the simulation of materials and molecules with non-nearest-neighbour couplings such as MnO (ref.27), high-temperature superconductors and DNA. The same superexchange concept can also be applied in cold atom experiments.

Benefits of a Recombination-Proficient Escherichia coli System for Adaptive Laboratory Evolution.

Over 80 years ago Fisher and Muller began a debate on the origins of sexual recombination. Although many aspects of sexual recombination have been examined at length, experimental evidence behind the behaviors of recombination in many systems and the means to harness it remain elusive. In this study, we sought to experimentally validate some advantages of recombination in typically asexual Escherichia coli and determine if a sexual strain of E. coli can become an effective tool for strain development.

The evolutionary mechanism of genome size

A genome is a set of DNA sequences encoding the complete genetic information of an organism, therefore more complex organisms are reasonably expected to have larger genomes. However, eukaryotic genome size vary drastically and seems to have no connection to the evolutionary complexity. Such an inconsistency between them is known as the C-value paradox. Here we briefly introduced the history of researches on genome size, and reviewed the advances and hypotheses of the researches on the relationships between genome size and evolutionary level, genome composition and some cell traits. At the top level of biological classification, the increase of evolutionary complexity is notably coupled with the augment of genetic information which leads to bigger genome sizes. Albeit there are overlapping between adjacent groups, the genome sizes rank upwards as evolutionary complexity, i.e, viruses cis -regulatory element sites, more alternative splicing genotypes, and higher allele exchange frequency, therefore endows a population higher genetic diversity and environmental adaptability. Thus noncoding DNA sequences can be accumulated on genome during evolution because they may promote the optimization of genes and the evolution of an organism. The bulk insertion of noncoding DNA does not apparently change an organism’s evolution complexity, but interrupts the correlation between genome size and evolutionary complexity, thereafter leads to the so-called C-value paradox. The evolutionary mechanism of genome size is often explained by two primary hypotheses: the natural selection theory and the neutral theory with genetic drift. We believe the former determines the significant changes in genome size on a mesoscale and the latter contributes to fluctuations in the genome size on a microscale. Molecular events may impose on genome size in diversified ways. While mutation rate and repeated sequences as transposons intend to enlarge genomes, some mechanism, as an example, piRNA can prevent a genome from growing. We emphasize the point that molecular variations bring changes to the genome size and advantageous changes be retained by natural selection.

PH-Sensitive Vesicles Formed by Amphiphilic Grafted Copolymers with Tunable Membrane Permeability for Drug Loading/Release: A Multiscale Simulation Study

By synergizing molecular dynamics and dissipative particle dynamics simulations, we investigate the assembly of amphiphilic grafted copolymers into vesicles and the loading/release of doxorubicin hydrochloride (DOX·HCl). The copolymers, PAE-g-PEGLA, comprise pH-sensitive poly(β-amino ester) grafted with hydrophilic poly(ethylene glycol) and hydrophobic poly(d,l-lactide). The vesicle formation is revealed to follow an aggregation–rearrangement mechanism, in which small clusters first form, then rearrange, and finally merge into bilayer-structured vesicles. The vesicle interior size and membrane thickness are substantially affected by the exchange quantity and frequency between tetrahydrofuran and water. At pH = 7, DOX·HCl is loaded into the vesicle interior, and the loading efficiency increases with increasing polymer concentration. At pH < 7, PAE blocks are protonated and hydrophilic, which causes the structure transition of membrane thus tuning membrane permeability for DOX·HCl release. When PLA blocks b...

Accountable Care Organizations and Transaction Cost Economics.

Using a Transaction Cost Economics (TCE) approach, this paper explores which organizational forms Accountable Care Organizations (ACOs) may take. A critical question about form is the amount of vertical integration that an ACO may have, a topic central to TCE. We posit that contextual factors outside and inside an ACO will produce variable transaction costs (the non-production costs of care) such that the decision to integrate vertically will derive from a comparison of these external versus internal costs, assuming reasonably rational management abilities. External costs include those arising from environmental uncertainty and complexity, small numbers bargaining, asset specificity, frequency of exchanges, and information "impactedness." Internal costs include those arising from human resource activities including hiring and staffing, training, evaluating (i.e., disciplining, appraising, or promoting), and otherwise administering programs. At the extreme, these different costs may produce either total vertical integration or little to no vertical integration with most ACOs falling in between. This essay demonstrates how TCE can be applied to the ACO organization form issue, explains TCE, considers ACO activity from the TCE perspective, and reflects on research directions that may inform TCE and facilitate ACO development.

Sci‐Thur PM – Brachytherapy 04: Commissioning and Implementation of a Cobalt‐60 High Dose Rate Brachytherapy Source

An Eckert &amp; Ziegler Bebig Co0.A86 cobalt 60 high dose rate (HDR) brachytherapy source was commissioned for clinical use. Long‐lived Co‐60 HDR sources offer potential logistical and economic advantages over Ir‐192 sources, and should be considered for low to medium workload brachytherapy departments where modest increases in treatment times are not a factor. In optimized plans, the Co‐60 source provides a similar dose distribution to Ir‐192 despite the difference in radiation energy. By switching to Co‐60, source exchange frequency can be reduced by a factor of 20, resulting in overall financial savings of more than 50% compared to Ir‐192 sources. In addition, a reduction in Physicist QA workload of roughly 200 hours over the 5 year life of the Co‐60 source is also expected. These benefits should be considered against the modest increases in average treatment time compared to those of Ir‐192 sources, as well as the centre‐specific needs for operating room shielding modification.

The Web of Life, the Tangled Bank, and the Frequency of Genetic Exchange

The Web of Life, the Tangled Bank, and the Frequency of Genetic Exchange

Study concerning the frequency of fluid exchanges, the dwell time and their impact in peritoneal dialysis in cats

A 11-year-old 3.1 kg, castrated, female Sphinx cat was referred to the Clinic of the Faculty of Veterinary Medicine Bucharest for acute onset vomiting, loss of appetite, anorexia, faintness, sharp breath, inability to exercise, oliguria and lethargy. Results from a complete blood (cell) count (CBC), serum chemical profile, and urinalysis submitted at that time were abnormal. The patient had hyperglycaemia (Glu-164 mg/dl), acute renal failure (Crea-3.4 mg/dl, BUN-117 mg/dl) and acute liver failure (ALT-744U/L, TBIL-11.8 mg/dl). The ALKP was 155U/L. The rectal temperature was 37,4 °C, the patient presented anaemic mucous membranes, mild dehydration (persistent skin fold thickness 2-3 seconds) and slight sensitivity to palpation in the renal lanyard. The established treatment consisted in peritoneal dialysis, rehydration and electrolyte balance, parenteral nutrition. We used PD4 peritoneal dialysis Dianeal 200 ml (1000 ml / sqm). The patient was submitted to intravenous fluidotherapy with 5% Dextrose, Sodium Chloride 0.9%, Aspatofort, Ondansetron, Metoclopramide and Duphalyte, CRI for 18 days. Abdominal ultrasound showed bile duct obstruction, abundant sludge in the gallbladder and mild modification in kidneys. Recommendation for oral treatment: Ipakitine bid, Azodyl bid and kidney diet food. The patient started to eat voluntary after 8 days of treatment. TBIL went up to 23.3 mg/ml after the first 7 days and then started to decrease until it reached 0.9 mg/dl at the end of the parenteral treatment. BUN and Creatinine values decreased to normal after the first 7 days of peritoneal dialysis and parenteral treatment. Peritoneal dialysis therapy plays an important role in renal failure in cats, especially in the elderly and weighing up to 10 kg. Elevated levels of creatinine and urea, hyperkalemia, hyper phosphatemia, or metabolic acidosis which do not yield to treatment can be solved using peritoneal dialysis. It also has a good effect in acute liver failure, cleaning the high levels of bilirubine.

The India–Japan strategic partnership: evolving synergy in the Indo-Pacific

ABSTRACTDefence and security cooperation between India and Japan have evolved steadily over the years and constitute a strong pillar of the bilateral relationship. Increasing frequency of defence exchanges along the entire spectrum is mutually beneficial. India views Japan as a potential source of considerable investment that can offer significant partnership opportunities for India to deepen its relations with the East. The article takes a brief historic account of bilateral relations and analyses the bilateral relations and its regional and global impact in the backdrop of Japanese Prime Minister Abe’s visit to India in December 2015. Prominent areas of cooperation such as strategic, defence and security along with economic cooperation are widely discussed in the backdrop of rapidly changing geopolitical calculus between the US and China.

When does inequality freeze an economy?

Inequality and its consequences are the subject of intense recent debate. Using a simplified model of the economy, we address the relation between inequality and liquidity, the latter understood as the frequency of economic exchanges. Assuming a Pareto distribution of wealth for the agents, that is consistent with empirical findings, we find an inverse relation between wealth inequality and overall liquidity. We show that an increase in the inequality of wealth results in an even sharper concentration of the liquid financial resources. This leads to a congestion of the flow of goods and the arrest of the economy when the Pareto exponent reaches one.

Is Journalism a Transnational Field? Asymmetrical Relations and Symbolic Domination in Online News

Are all transnational exchanges ‘fielded’? This article explores the limits of the concept of transnational field by focusing on the case of journalism. At first glance, journalism might seem to be the perfect example of a transnational field. The frequency, speed and extent of international exchanges between media outlets has increased dramatically with the development of online news, leading media scholars to develop the concept of ‘global news’. Yet I argue that such international exchanges do not necessarily constitute a field. Using ethnographic methods, I analyse the circulation of online news between the United States and France, two countries with strikingly different journalistic traditions. Specifically, I compare two editorial partnerships between US and French websites, one linking prestigious online magazines across the Atlantic and the other connecting tabloid-oriented news sites. I find that editorial content does not circulate seamlessly between the two countries. Based on this study, the article proposes three criteria that must be met for transnational fields to exist: competition over the legitimate definition of the field, reciprocal field effects, and the existence of common stakes. More broadly, the article contributes to defining the limits of the concept of ‘transnational field’ for the study of international exchanges.

Investigation on influence factors of gernal surgeon growth

Objective To investigate the general surgeon growth time, and to probe into the factors affecting the surgeon growth. Methods 72 surgeons who worked more than 15 years in the field of general surgery in 12 hospitals of Gansu Province were investigated, focusing on education, resident rotation training, teachers' qualification, refresher training, the frequency of intra-hospital technical exchange, and scale of hospital employed. SPSS 18.0 statistical software was applied to analyze the data. t test was used in com-parison between groups, and multiple groups were compared by using single factor analysis of variance. Results The surgeon growth time was (9.84±1.51) years averagely. In the process of growing up, the growth time of the general surgeons who experienced hospital resident rotated training, refresher training, intra-hospital technical exchange was significantly shorter than that of no-related-experienced surgeons. The higher the education, the higher the quality of the teachers and the higher the level of medical institutions, the shorter the doctor's growth time. Conclusion In the same medical institutions, the resident rotated training, the teacher's qualification, higher hospital training, and the frequency of intra-hospital technical exchange have the positive function to the surgeon's general growth, so in making young doctor training plan we should consider the value of the above-mentioned factors. Key words: General surgeons; Growth time; Influence factors; Investigation