Canadian Science Publishing

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Canadian Science Publishing (CSP) is committed to enhancing the reach, rigour, and relevance of science so that people can find, trust, and use it. Established in 1929, Canadian Science Publishing is Canada’s largest not-for-profit publisher and has grown to publish 22 international scientific journals across natural and physical sciences and engineering, including three open access journals. Canadian Science Publishing is dedicated to enhancing the integrity, relevance, and impact of research globally, while promoting open science, diversity, and sustainability. Committed to equitable access, Canadian Science Publishing partners with over 25 scientific societies to remove barriers and empower the global research community. For more information, please visit www.cdnsciencepub.com.

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Molecular Dynamics Screening For New Kinetic Inhibitors Of Methane Hydrate
(Canadian Science Publishing, 2015-03-13) Oluwunmi, Paul A; Finney, Aaron R; Rodger, Mark
The development of polymeric and oligomeric chemical additives that can control the nucleation and growth of gas hydrates remains a topic of major research interest, with important implications for energy security and the environment. In this paper we present a molecular dynamics study of eight different oligomeric compounds that have been proposed as potential kinetic inhibitors for methane hydrate. The results show that statistically significant variations in hydrate formation, induced by the chemical additive, can be observed within a relatively modest series of molecular dynamics simulations, thus opening the way for computational screening for optimal additives to control hydrate formation. One amino acid oligomer, asparagine, was found to be more active than a number of synthetic inhibitors, including PVCap.
Mycobacterium smegmatis synthesizes in vitro androgens and estrogens from different steroid precursors.
(Canadian Science Publishing, 2015-04-06) Dlugovitzky, Diana G. DGD ; Fontela, María Sol ; Lamas, Diego J Martinel- ; Valdez, Ricardo A ; Romano, Marta C.
Fast-growing mycobacteria as Mycobacterium sp and smegmatis degrade natural sterols. They are a model to study tuberculosis. Interestingly, Mycobacterium smeg (M. smeg) have been found in river effluents derived from paper production and therefore it would important to gain further insight in their capacity to synthesize steroids that are potential endocrine disruptors affecting the development and reproduction of fishes. To our knowledge, the capacity of M. smeg to synthesize estrogens and even testosterone had not been reported. Therefore, the objective of this study was to investigate the capacity of M. smeg to synthesize in vitro testosterone and estrogens from tritiated precursors and to investigate the metabolic pathways involved. Results obtained by thin layer chromatography showed that 3H-progesterone was transformed to 17OH-progesterone, androstenedione, testosterone, estrone and estradiol after 6, 12 or 24 h of incubation. 3H-androstenedione was transformed to testosterone and estrogens mainly estrone, and 3H-testosterone to estrone and androstenedione. Incubation with 3H-dehydroepiandrosterone rendered androstendiol, testosterone and estrogens. The ability of transforming less potent sex steroids as androstenedione and estrone to other more active like testosterone and estradiol or viceversa suggests that M.smeg influence the amount of self synthesized strong androgens and estrogens and can transform those found in the environment.
Evolution of the Hazelton arc near Terrace, British Columbia: Stratigraphic, geochronological, and geochemical constraints on a Late Triassic-Early Jurassic arc and Cu-Au porphyry belt
(Canadian Science Publishing, 2015-04-07) Barresi, Tony ; Nelson, JoAnne L. ; Dostal, Jaroslav ; Friedman, Richard M.
Understanding the development of island arcs that accreted to the North American craton is critical to deciphering the complex geological history of the Canadian Cordillera. In the case of the Hazelton arc (part of the Stikine terrane, or Stikinia) in northwestern British Columbia, understanding arc evolution also bears on the formation of spatially associated porphyry Cu-Au, epithermal, and volcanogenic massive sulfide deposits. The Hazelton Group is a regionally extensive, long-lived and exceptionally thick Upper Triassic to Middle Jurassic volcano-sedimentary succession considered to record a successor arc that was built upon the Paleozoic and Triassic Stikine and Stuhini arcs. In central Stikinia, near Terrace, British Columbia, the lower Hazelton Group (Telkwa Formation) comprises three volcanic-intrusive complexes (Mt. Henderson, Mt. O’Brien, and Kitselas) which, at their thickest, constitute almost 16 km of volcanic stratigraphy. Basal Telkwa Formation conglomerates and volcanic rocks were deposited unconformably on Triassic and Paleozoic arc-related basement. New U-Pb zircon ages indicate that volcanism initiated by ca. 204 Ma (latest Triassic). Detrital zircon populations from the basal conglomerate contain abundant 205-233 Ma zircons, derived from regional unroofing of older Triassic intrusions. Eleven kilometres higher in the section, ca. 194 Ma rhyolites show that arc construction continued for >10 My. Strata of the Nilkitkwa Formation (upper Hazelton Group) with a U-Pb zircon age of 178.90 ± 0.28 Ma represent waning island arc volcanism. Telkwa Formation volcanic rocks have bimodal silica concentrations ranging from 48.1 - 62.8 and 72.3 - 79.0 wt.%, and display characteristics of subduction-related magmatism (i.e. calc-alkaline differentiation with low Nb and Ti and high Th concentrations). Mafic to intermediate rocks form a differentiated suite that ranges from high-Al basalt to medium-high K andesite. They were derived from hydrous melting of isotopically juvenile spinel lherzolite in the mantle wedge and from subsequent fractional crystallization. Compared to basalts and andesites (εNd = +5 to +5.5), rhyolites have higher positive εNd values (+5.9 - +6.0) and overlapping incompatible element concentrations, indicating that they are not part of the same differentiation suite. Rather, the rhyolites formed from anatexis of arc crust, probably caused by magmatic underplating of the crust. This study documents a temporal and spatial co-occurrence of Hazelton Group volcanic rocks with a belt of economic Cu-Au porphyry deposits (ca 205 – 195 Ma) throughout northwestern Stikinia. The coeval relationship is attributed to crustal underplating and intra-arc extension associated with slab rollback during renewed or reconfigured subduction beneath Stikinia, following the demise of the Stuhini arc in the Late Norian.
Slipstream: an Early Holocene Slump and Turbidite Record from the Frontal Ridge of the Cascadia Accretionary Wedge off Western Canada and Paleoseismic Implications
(Canadian Science Publishing, 2015-04-07) Hamilton, T.S. ; Enkin, Randolph J ; Riedel, Michael ; Rogers, Garry C ; Pohlman, John W ; Benway, Heather M.
Slipstream Slump, a well-preserved 3 km wide sedimentary failure from the frontal ridge of the Cascadia accretionary wedge 85 km off Vancouver Island, Canada, was sampled during CCGS Tully cruise 2008007PGC along a transect of five piston cores. Shipboard sediment analysis and physical property logging revealed 12 turbidites interbedded with thick hemipelagic sediments overlying the slumped glacial diamict. Despite the different sedimentary setting, atop the abyssal plain fan, this record is similar in number and age to the sequence of turbidites sampled farther to the south from channel systems along the Cascadia Subduction Zone, with no extra ones present in this local record. Given the regional physiographic and tectonic setting, megathrust earthquake shaking is the most likely trigger for both the initial slumping and subsequent turbidity currents, with sediments sourced exclusively from the exposed slump face of the frontal ridge. Planktonic foraminifera picked from the resedimented diamict of the underlying main slump have a disordered cluster of 14C ages between 12.8 and 14.5 ka. For the post-slump stratigraphy, an event-free depth scale is defined by removing the turbidite sediment intervals and using the hemipelagic sediments. Nine 14C dates from the most foraminifera-rich intervals define a nearly constant hemipelagic sedimentation rate of 0.021 cm/yr. The combined age model is defined using only planktonic foraminiferal dates and Bayesian analysis with a Poisson-process sedimentation model. The age model of ongoing hemipelagic sedimentation is strengthened by physical properties correlations from Slipstream events to the turbidites for the Barkley Canyon site 40 km south. Additional modelling addressed the possibilities of seabed erosion or loss and basal erosion beneath turbidites. Neither of these approaches achieves a modern seabed age when applying the commonly used regional marine 14C reservoir age of 800 years (ΔR=400 years). Rather the top of the core appears to be 400 years in the future. A younger marine reservoir age of 400 years (ΔR=0 years) brings the top to the present and produces better correlations with the nearby Effingham Inlet paleo-earthquake chronology based only on terrestrial carbon requiring no reservoir correction. The high resolution dating and facies analysis of Slipstream Slump in this isolated slope basin setting demonstrates that this is also a useful type of sedimentary target for sampling the paleoseismic record in addition to the more studied turbidites from submarine canyon and channel systems. The first 10 turbidites at Slipstream Slump were deposited between 10.8 and 6.6 ka, after which the system became sediment-starved and only 2 more turbidites were deposited. The recurrence interval for the inferred frequent Early Holocene megathrust earthquakes is 460 ± 140 years, compatible with other estimates of paleoseismic megathrust earthquake occurrence rates along the subduction zone.
Development, Reliability and Validity Testing of Toddler NutriSTEP®: A Nutrition Risk Screening Questionnaire for Children 18-35 Months of Age
(Canadian Science Publishing, 2015-04-10) Randall Simpson, Janis; Gumbley, Jillian; Whyte, Kylie; Lac, Jane; Morra, Crystal; Rysdale, Lee; Turfryer, Mary; McGibbon, Kim; Beyers, Joanne; Keller, Heather
Background /Objectives Nutrition is vital for optimal growth and development of young children. Nutrition risk screening can facilitate early intervention when followed by nutritional assessment and treatment. NutriSTEP® is a valid and reliable nutrition risk screening questionnaire for preschoolers (3-5 years). A need was identified for a similar questionnaire for toddlers (18-35 months). The purpose was to develop a reliable and valid Toddler NutriSTEP®. Subjects/Methods Toddler NutriSTEP® was developed in four phases. Content and face validity were determined with a literature review, parent focus groups (n=6, 48 participants) and experts (n=13) (Phase A). A draft questionnaire was refined with key intercept interviews of 107 parents/caregivers (Phase B). Test-retest reliability (Phase C), based on intra-class correlations (ICC), Kappa (ĸ) statistics, and Wilcoxon tests was assessed with 133 parents/caregivers. Criterion validity (Phase D) was assessed using Receiver Operating Characteristic (ROC) curves by comparing scores on the Toddler NutriSTEP® to a comprehensive nutritional assessment of 200 toddlers with a registered dietitian (RD). Results The Toddler NutriSTEP® was reliable between two administrations (ICC=0.951, F=20.53, p
Analysis of biofilm formation by intestinal lactobacilli
(Canadian Science Publishing, 2015-04-14) Slizova, Magdalena; Nemcova, Radomira; Madar, Marian; Hadryova, Jana; Gancarcikova, Sona; Popper, Miroslav; Pistl, Juraj
In this study, biofilm forming potential of intestinal Lactobacillus reuteri strains under different culture conditions was characterized by microtiter plate biofilm assays. Moreover, the spatial organization of exogenously applied L. reuteri L2/6 (a pig isolate) at the specific locations in gastrointestinal tract of monoassociated mice was investigated by FISH. We did not detect biofilm formation by tested strains in nutrient-rich MRS medium. On the contrary, a highly positive biofilm formation was observed in medium with lower accessibility to the carbon sources and lack of salts. The results obtained confirmed the significant role of Tween 80 and the quantity and nature of the sugars in the growth medium on biofilm formation. The omission of Tween 80 in MRS medium favored the formation of biofilm. Abundant biofilm formation was detected in the presence of lactose, galactose and glucose. However, gradual increase in sugars concentration triggered significant decrease in biofilm formation. In addition, conditions related to the gastrointestinal environment such as low pH, the presence of bile and mucins highly modulated biofilm production. This effect seems to be dependent on the specificity and properties of the medium used for cultivation. From the evidence provided by this study we conclude that the biofilm formation capacity of L. reuteri is strongly dependent on the environmental factors and culture medium used.
The animal gut as a melting pot for horizontal gene transfer
(Canadian Science Publishing, 2015-04-18) Shterzer, Naama ; Mizrahi, Itzhak
In this mini review we examine horizontal gene transfer (HGT) events in the mammalian gastrointestinal tract and their role in the evolutionary adaptation of microorganisms to the gut environment. We explore the notion of mammalian gut as a melting pot of genetic exchange, resulting in the large extent of HGT occurrence. Keywords: Horizontal gene transfer; gut microbiome
Inhibition and Compressive-Strength Performance of Na₂Cr₂O₇ and C₁₀H₁₄N₂Na₂O₈.2H₂O in Steel-Reinforced Concrete in Corrosive Environments
(Canadian Science Publishing, 2015-04-19) Okeniyi, Joshua Olusegun ; Oladele, Isaac Oluwaseun ; Omoniyi, Oluwafemi Michael ; Loto, Cleophas Akintoye ; Popoola, Abimbola Patricia
This paper studied corrosion-inhibition and compressive-strength performances of Na
IS256 Abolishes gelatinase activity and biofilm formation in a mutant of the nosocomial pathogen Enterococcus faecalis V583
(Canadian Science Publishing, 2015-04-20) Perez, Marta; Calles-Enríquez, Marina; del Rio, Beatriz; Ladero, Victor; Martin, M Cruz; Fernandez, Maria; Alvarez, Miguel A
Enterococcus faecalis is one of the most controversial species of lactic acid bacteria. Some strains are used as probiotic, while others are associated with severe and life threatening nosocomial infections. Their pathogenicity depends on the acquisition of multi drug resistance and virulence factors. Gelatinase, which is required in the first steps of biofilm formation, is an important virulence determinant involved in E. faecalis pathogenesis including endocarditis and peritonitis. The gene that codes for gelatinase (gelE) is controlled by the Fsr quorum-sensing system, whose encoding genes (fsrA, fsrB, fsrC, and fsrD) are located immediately upstream of gelE. The integration of a DNA fragment into the fsr locus of a derived mutant of E. faecalis V583 suppressed the gelatinase activity and prevented biofilm formation. Sequence analysis indicated the presence of IS256 integrated into the fsrC gene at nucleotide position 321. Interestingly, IS256 is also associated with biofilm formation in Staphylococcus epidermidis and Staphylococcus aureus. This is the first description of an insertion sequence that prevents biofilm formation in E. faecalis.
The lingering effects of a busted myth—false time limits in stroke rehabilitation
(Canadian Science Publishing, 2015-04-21) Sun, Yao; Boots, Joanne; Zehr, E. Paul
It was once falsely believed that neurological and functional recovery after stroke occurred only in the first six months after lesion. The perception of this "6 month myth" continues to negatively impact the attitudes of patients towards their rehabilitation and on the clinicians and therapists making optimal training plans. Here we briefly outline some evidence that debunked the “6-month myth”, where the concept of this temporal limit may have originated, and the lingering misunderstanding that individuals with stroke reach a plateau of recovery after six months even with rehabilitation training. We present evidence that significant functional improvement can occur years after stroke when rehabilitation training is applied. We frame the concepts of active and passive neurological recovery and that active neurological recovery continues far beyond any temporal limit. Because the effects of this busted “6 month myth” persist, we aim to remind active physicians, therapists, exercise professionals and people with stroke to continuously seek opportunities for active rehabilitation training. Meanwhile, trained and certified exercise professionals can play critical roles in facilitating rehabilitative training for community-dwelling stroke survivors.
Maximal power output during incremental cycling test is dependent on the curvature constant of the power-time relationship
(Canadian Science Publishing, 2015-04-23) Souza, Kristopher Mendes de; de Lucas, Ricardo Dantas; do Nascimento Salvador, Paulo Cesar; Guglielmo, Luiz Guilherme Antonacci; Caritá, Renato Aparecido Corrêa; Greco, Camila Coelho; Denadai, Benedito Sérgio
The aim of this study was to investigate whether the maximal power output (P
Feces of feedlot cattle contain a diversity of bacteriophages that lyse non-O157 Shiga toxin-producing Escherichia coli
(Canadian Science Publishing, 2015-04-27) Wang, Jiaying ; Niu, Yan D ; Chen, Jinding ; Anany, Hany ; Ackermann, Hans W ; Johnson, Roger P ; Ateba, Collins Njie ; Stanford, Kim ; McAllister, Tim A.
This study aimed to isolate and characterize bacteriophages that lyse non-O157 Shiga toxin-producing Escherichia coli (STEC) from cattle feces. Of 37 non-O157 STEC-infecting phages isolated, O26- (vB_EcoS_AXO26A, vB_EcoM_AYO26A, vB_EcoM_AYO26B), O103- (vB_EcoS_AXO103A, vB_EcoP_AYO103A), O111- (vB_EcoM_AXO111A, vB_EcoM_AYO111A), O121- (vB_EcoM_AXO121A, vB_EcoM_AXO121B) and O145- (vB_EcoM_AYO145A, vB_EcoM_AYO145B) targeting phages were further characterized. Transmission electron microscopy showed the 11 isolates belonged to 3 families and 6 genera: the families Myoviridae (types rV5, T4, ViI, O1), Siphoviridae (type T5) and Podoviridae (type T7). Genome size of the phages as determined by pulsed-field gel electrophoresis ranged from 38 to 197 kb. Excluding phages AXO26A, AYO103A, AYO145A and AYO145B, all other phages were capable of lysing more than one clinically important strain from serogroups of O26, O91, O103, O111, O113, O121 and O128, but none exhibited infectivity across all serogroups. Moreover, phages AYO26A, AXO121A and AXO121B were also able to lyse 4 common phage types of STEC O157:H7. Our findings show that a diversity of non-O157 STEC-infecting phages are harbored in bovine feces. Phages AYO26A, AYO26B, AXO103A, AXO111A, AYO111A, AXO121A and AXO121B exhibited a broad host range against a number of serogroups of STEC and have potential for the biocontrol of STEC in the environment.
New report of additional Enterobacterial species causing Wilt in West Bengal, India.
(Canadian Science Publishing, 2015-04-27) Sarkar, Shamayeeta ; Chaudhuri, Sujata
Ralstonia solanacearum, is known to be the most prominent causal agent of bacterial wilt worldwide. It has a wide host range comprising of solanaceous and non-solanaceous plants. Typical symptoms of the disease are leaf wilt, browning of vascular tissues and collapsing of the plant. With the objective of studying the diversity of bacterial wilt causing pathogen in West Bengal, samples of diseased symptomatic crops and adjacent symptomatic and asymptomatic weeds from widespread locations in West Bengal were collected. A majority of these strains (68 out of 71) were not found to be R.solanacearum through routine molecular identification test specific to ‘R. solanacearum species complex’. A presumptive identification of these isolates with conventional biochemicals, an extensive testing of pathogenicity of a subset involving greenhouse trials fulfilling Koch’s Postulate test and SEM analysis for presence of the pathogen in diseased plants were done. 16s rDNA sequencing of a subset of these strains (Genbank- Accession No. JX880249-JX880251) and analysis of sequences with nBLAST programme showed a high similarity (97-99%) to the sequences of Enterobacteriaceae group available in the Genbank. Molecular phylogeny further established the taxonomic position of the strains. The three bacterial strain cultures have been submitted to MTCC, Institute of Microbial Technology, Chandigarh, India and identified as Klebsiella oxytoca, Enterobacter cowanii and Klebsiella oxytoca respectively. Although Enterobacter sp. has previously been reported causing wilt in many plants, susceptibility of most of the dedicated hosts of R.solanacearum to wilt caused by Enterobacter and other bacteria from Enterobacteriaceae is being reported for the first time in this work.
Delay in post-ovariectomy estrogen-replacement negates estrogen-induced augmentation of post-exercise muscle satellite cell proliferation
(Canadian Science Publishing, 2015-04-27) Mangan, Gary; Iqbal, Sobia; Hubbard, Andrew; Hamilton, Victoria; Bombardier, Eric; Tiidus, Peter M.
Aim: This study examined the effects of a delay in post-ovariectomy replacement of 17β-estradiol (estrogen) on the post-exercise proliferation of muscle satellite cells. Methods: Nine-week old, ovariectomized female Sprague-Dawley rats (n=64) were divided into eight groups based on: estrogen status (0.25 mg estrogen pellet or sham), exercise status (90 min run @ 17 m/min, -13.5° or unexercised) and estrogen replacement (“proximal”; estrogen replacement within two- weeks or “delayed”; estrogen replacement at eleven-weeks following ovariectomy). Results: Significant increases in satellite cells were found in the soleus and white gastrocnemius muscle (immunofluorescent co-localization of nuclei with Pax7) 72 hrs following eccentric exercise (p
Influences on male reproductive success in long-lived Blanding's Turtles (Emydoidea blandingii)
(Canadian Science Publishing, 2015-04-27) McGuire, Jeanette ; Congdon, Justin ; Kinney, O.M. ; Osentoski, Matt ; Scribner, Kim T.
Knowing how the number and qualities of mates influence male reproductive success (RS) can help interpret mating system dynamics that are important for conservation efforts. We combined parentage data (1999-2006) with data from a long-term life history study (1953-2007) of Blanding's Turtles (Emydoidea blandingii, Holbrook 1838) on the University of Michigan's E. S. George Reserve to document the relative influence of mate number and quality on male RS. Blood samples were taken from > 92% of resident adults and tissue samples were taken from 723 hatchlings from 92 nests of 54 females over 8 nesting seasons. The incidence of multiple paternity averaged 41.6% (N = 77), was variable among years (min-max = 15.4-55.6%), and was positively associated with female age, body size, and clutch size. Repeat paternity was observed in 69.9% of sequential clutches of the same female separated by 1-7 years. Male RS was variable (1-40 offspring) and was positively associated with the number of mates and clutches sired. The youngest male to sire offspring was 22 years old. Adult movements that result in encountering different mates and/or the ability to use attributes (e.g., size or age) to identify high-quality mates have the potential to substantially increase RS.
A GIS-BASED METHOD FOR DEPICTING THE CHARACTERISTICS OF MESOSCALE EDDIES: A CASE STUDY IN THE NORTHERN SOUTH CHINA SEA
(Canadian Science Publishing, 2015-04-27) Li, Ce; Du, Yunyan; Liang, Fuyuan; Yi, Jiawei; Lakhan, V. Chris
The paper presents a Geographical Information System (GIS)-based method for depicting the characteristics, particularly the internal structures and evolutionary processes, of mesoscale eddies. This was done by examining topologic relations among closed Sea Surface Height (SSH) contours which were reconstructed from the Naval Research Laboratory (NRL) Layered Ocean Model (NLOM). Different scenarios of the topological relations among the contour lines permitted the identification of the outermost outline of eddies and the depiction of the number of cores in each mesoscale oceanic eddy. With full consideration of the internal structure of the eddies, we then reconstructed the evolutionary processes of these eddies and the results were compared with empirical observations on three long-lived mesoscale eddies in the northern South China Sea (SCS). Tracking results were similar, thereby validating our method as being efficient and robust in reconstructing mesoscale ocean eddies, especially their evolutionary processes based on their internal structures.
The Pioneer Anomaly in Covariant Theory of Gravitation
(Canadian Science Publishing, 2015-04-28) Fedosin, Sergey G.
The difference of equations of motion in the covariant theory of gravitation and in the general theory of relativity is used for explanation of Pioneer anomaly. Calculation shows that the velocities of a spacecraft in both theories at equal distances can differ by several cm/s. This leads also to possible explanation of flyby anomaly and disturbances of comet which are not taken into account by the general theory of relativity.
The Time for an Updated Canadian Food Guide Has Arrived
(Canadian Science Publishing, 2015-04-28) Jessri, Mahsa; L'Abbé, Mary R.
Canada has published food guides since 1942 and the latest version, “Eating Well with Canada’s Food Guide” (EWCFG) was released in 2007. The EWCFG is largely based on meeting nutrient requirements while we are now in need of a food guide with strong guidance on the role of diet in preventing chronic diseases. This article systematically analyses the process and assumptions behind the EWCFG and presents suggestions for needed revisions to the next food guide.
POTENTIAL ERGOGENIC ACTIVITY OF GRAPE JUICE IN RUNNERS
(Canadian Science Publishing, 2015-04-28) Toscano, Lydiane Tavares; Tavares, Renata Leite; Toscano, Luciana Tavares; Silva, Cássia Surama Oliveira da; Almeida, Antônio Eduardo Monteiro de; Biasoto, Aline Camarão Telles; Golçalves, Maria da Conceiçao Rodrigues; Silva, Alexandre Sérgio
Recent studies have indicated that certain food products have ergogenic potential similar to that of sports supplements. The present study aimed to investigate the potential ergogenic effect of integral purple grape juice on the performance of recreational runners. Twenty eight volunteers of both genders (39.8 ± 8.5 years; peak oxygen consumption [VO2peak] of 43.2 ± 8.5 mL/kg/min) were randomized into either a group that received grape juice (grape juice group – GJG, n=15; 10 mL/kg/min for 28 days) or a group that received an isocaloric, isoglycemic and isovolumetric control beverage (control group – CG, n=13). A time-to-exhaustion exercise test, anaerobic threshold test and aerobic capacity test were performed, together with assessments of markers of oxidative stress, inflammation, immune response and muscle injury, performed at baseline and 48 hours after the supplementation protocol. The GJG showed a significant increase (15.3%) in running time-to-exhaustion (p=0.002) without significant improvements in either anaerobic threshold (3.6%; p=0.511) or aerobic capacity (2.2%; p=0.605). In addition, GJG exhibited significant increases in total antioxidant capacity (38.7%; p=0.009), vitamin A (11.8%; p=0.016) and uric acid (28.2%; p=0.005), whereas alpha-1-acid glycoprotein significantly decreased (20.2%; p=0.006) and high-sensitivity C-reactive protein levels remained unchanged. In contrast, no significant changes occurred in any of these variables in the CG. Concluded that supplementation with purple grape juice shows an ergogenic effect in recreational runners by promoting increased time to exhaustion, accompanied by increased antioxidant activity and a possible reduction in inflammatory markers.
Vitamin D, Phosphate and Vasculotoxicity
(Canadian Science Publishing, 2015-04-30) Brown, Ronald B; Haq, Afrozul; Stanford, Charles F; Razzaque, Mohammed S
Vascular calcification is a complex process that is formed by the ectopic deposition of calcium-phosphate hydroxyapatite. Medial and intimal vascular calcification is frequently present in patients with diabetes mellitus and chronic kidney disease (CKD) which markedly increases the morbidity and mortality of these patients. Increased serum calcium and phosphate levels, along with the use of active vitamin D metabolites, are commonly believed to be related to the evolvement of vascular wall mineralization in CKD patients. Because CKD patients have lower serum levels of vitamin D, they are routinely prescribed with vitamin D supplements which exert a dualistic role that is both healthful and harmful in these patients, perhaps protecting bone health, at the expense of promoting vascular pathology. This brief article explains how reducing phosphate burden in CKD patients could minimize vitamin D-associated vascular wall calcification.

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