A walk in the PARC: developing and implementing 21st century chemical risk assessment in Europe.

Current approaches for the assessment of environmental and human health risks due to exposure to chemical substances have served their purpose reasonably well. Nevertheless, the systems in place for different uses of chemicals are faced with various challenges, ranging from a growing number of chemicals to changes in the types of chemicals and materials produced. This has triggered global awareness of the need for a paradigm shift, which in turn has led to the publication of new concepts for chemical risk assessment and explorations of how to translate these concepts into pragmatic approaches. As a result, next-generation risk assessment (NGRA) is generally seen as the way forward. However, incorporating new scientific insights and innovative approaches into hazard and exposure assessments in such a way that regulatory needs are adequately met has appeared to be challenging. The European Partnership for the Assessment of Risks from Chemicals (PARC) has been designed to address various challenges associated with innovating chemical risk assessment. Its overall goal is to consolidate and strengthen the European research and innovation capacity for chemical risk assessment to protect human health and the environment. With around 200 participating organisations from all over Europe, including three European agencies, and a total budget of over 400 million euro, PARC is one of the largest projects of its kind. It has a duration of seven years and is coordinated by ANSES, the French Agency for Food, Environmental and Occupational Health & Safety.

NF-κB-mediated effects on behavior and cartilage pathology in a non-invasive loading model of post-traumatic osteoarthritis.

OBJECTIVE: This study aimed to examine the temporal activation of NF-κB and its relationship to the development of pain-related sensitivity and behavioral changes in a non-invasive murine knee loading model of PTOA. METHOD: Following knee injury NF-κB activity was assessed longitudinally via in vivo imaging in FVB. Cg-Tg (HIV-EGFP,luc)8Tsb/J mice. Measures of pain-related sensitivity and behavior were also assessed longitudinally for 16 weeks. Additionally, we antagonized NF-κB signaling via intra-articular delivery of an IκB kinase two antagonist to understand how local NF-κB inhibition might alter disease progression. RESULTS: Following joint injury NF-κB signaling within the knee joint was transiently increased and peaked on day 3 with an estimated 1.35 p/s/cm2/sr (95% CI 0.913.1.792 p/s/cm2/sr) fold increase in signaling when compared to control joints. Furthermore, injury resulted in the long-term development of hindpaw allodynia. Hyperalgesia withdrawal thresholds were reduced at injured knee joints, with the largest reduction occurring 2 days following injury (estimate of between group difference 129.1 g with 95% CI 60.9,197.4 g), static weight bearing on injured limbs was also reduced. Local delivery of an NF-κB inhibitor following joint injury reduced chondrocyte death and influenced the development of pain-related sensitivity but did not reduce long-term cartilage degeneration. CONCLUSION: These findings underscore the development of behavioral changes in this non-invasive loading model of PTOA and their relationships to NF-κB activation and pathology. They also highlight the potential chondroprotective effects of NF-κB inhibition shortly following joint injury despite limitations in preventing the long-term development of joint degeneration in this model of PTOA.

Experimental evidences that P21 protein controls Trypanosoma cruzi replication and modulates the pathogenesis of infection.

P21 is a protein secreted by Trypanosoma cruzi (T. cruzi). Previous studies have shown a spectrum of biological activities performed by P21 such as induction of phagocytosis, leukocyte chemotaxis and inhibition of angiogenesis. However, the activity of P21 in T. cruzi infection remains unknown. Here, we reported the role of P21 in mice harboring late T. cruzi infection. Treatment with recombinant P21 protein (rP21) reduced parasite load and angiogenesis, and induced fibrosis in the cardiac tissue of infected mice. In addition, rP21 reduced the growth of epimastigotes, inhibited intracellular replication of amastigotes and modulated the parasite cell cycle. Our data suggest that P21 controls parasite replication in the host, supporting the survival of both parasite and host.

Evaluation of apoptosis/necrosis and cytokine release provoked by three root canal sealers in human polymorphonuclears and monocytes.

AIM: To evaluate the in vitro cytotoxicity and cytokine release of three fresh root canal sealers and to determine the type of cell death they induce. METHODOLOGY: The sealers tested were Sealer 26 (S26), AH Plus (AHP), and Endosequence BC Sealer (END). Fresh sealers were cultivated in contact with monocytes and polymorphonuclears (PMNs) obtained from the peripheral blood of humans. Cell viability, apoptosis and necrosis were analysed at 4 h (PMNs) or 24 h (monocytes) using Annexin-V and propidium iodide in a cytometer. The supernatants were used to quantify Interleukin (IL)-4, IL-6, IL-10, IL-12 and tumour necrosis factor-α (TNF-α) in monocytes and IL-8 in PMNs by ELISA. One-way ANOVA and the Tukey post-test were used to compare data for cytotoxicity, and the multiple T-test was used to determine the differences between sealers in the release of cytokines that were statistically significant. RESULTS: After 4 h of treatment, S26 was associated with greater cell viability than the other sealers (P < 0.05) in the PMN culture and had similar values of necrosis as END (P > 0.05). After 24 h of treatment, AHP and END had greater monocyte cell viability than S26 (P < 0.05), which had more necrosis (P < 0.05). END had the lowest levels of IL-12 compared to the other sealers (P < 0.05) and higher levels of IL-6 compared to S26 (P < 0.05). The tested sealers did not differ in the release of IL-8, IL-10, TNF-α and IL-4 (P > 0.05). CONCLUSIONS: The effect of toxic agents released varied depending on the cell type studied. The composition of the sealers appeared to alter the form of self-regulation in the production of these cytokines by cells.

Quercetin influences in vitro maturation, apoptosis and metabolically active mitochondria of goat oocytes.

SummaryThe present study aimed to investigate the effect of quercetin as an alternative antioxidant to cysteamine on in vitro maturation. Oocytes were collected from goat ovaries, destined for in vitro maturation and distributed into three groups: CIS group, oocytes were immersed in MIV base medium; in Groups Q4 and Q8, oocytes were immersed in the medium of the CIS group, adding 4 µM or 8 µM of quercetin, respectively, and cultured for 24 h at 38.5°C with 5% CO2. The CIS and Q4 groups presented the same percentage of expanded cumulus cells, but the per cent in the Q8 group was significantly lower than that of the other groups (P<0.05). The oocyte retraction rate in the Q8 group was higher (P<0.05) than in the CIS and Q4 groups. Treatment with 8 µM of quercetin presented a lower proportion of expanded oocytes than the CIS group and 4 µM of quercetin (P<0.05). The percentage of MII oocytes was higher in the Q4 group than in the CIS group (P<0.05), but the percentages in the CIS and Q8 groups were similar. The rate of apoptosis was higher in the CIS group than in the other groups (P<0.05). In addition, oocytes matured with 4 µM quercetin showed higher mitochondrial activity than matured oocytes in the CIS and Q8 groups (P<0.05). In conclusion, 4 µM of quercetin can be used as an alternative to cysteamine in the in vitro maturation of goat oocytes.

Flexibility is associated with motor competence in schoolchildren.

Available data on the associations between motor competence (MC) and flexibility are limited and result inconclusive. This study aims to examine the relationship between flexibility and MC in children. The sample comprised 596 Portuguese children (47.1% girls) aged 9.7 ± 0.6 years. Motor competence was evaluated with the body coordination test, Körperkoordination Test für Kinder. Cardiorespiratory fitness (20-m shuttle run), muscular strength (curl-up and push-up tests), and flexibility (back-saver sit and reach and trunk-lift tests) were evaluated using the Fitnessgram Test Battery. Z-scores by age and gender for the physical fitness tests were constructed. Analysis of variance and regression analysis were performed. Participants in the healthy zone groups of both flexibility tests exhibited significantly better scores of MC than the participants under the healthy zone (P < 0.001). Back-saver sit and reach and trunk-lift Z-scores, either individually or as a sum, were significant predictors of MC (P < 0.05 for all) after adjustments for the other physical fitness components, age, body mass index, and socioeconomic status, in both genders. Our findings highlight the importance of promoting and developing flexibility, as well as the other health-related physical fitness components in schoolchildren to reach adequate levels of MC.

Contribution of morphoagronomic traits to grain yield and earliness in grain sorghum.

Given the importance of selecting lines to obtain hybrids, we aimed to verify the relationship between morphological traits that can be used as the criteria for the selection of sorghum lines with high grain yield and earliness. A total of 18 traits were evaluated in 160 sorghum elite lines, in an incomplete block design with two replicates. A correlation network was used to graphically express the estimates of phenotypic and genotypic correlations between the traits. Two path analyses were processed, the first considering grain yield and the second considering flowering as the principle dependent variable. In general, most of the variation in the grain yield and flowering of sorghum lines was explained by the traits evaluated. Selecting sorghum lines with greater width of the third leaf blade from flag leaf, panicle weight, and panicle harvest index might lead to increased grain yield, and selecting sorghum genotypes with higher plant height might lead to reduced earliness and increased grain yield. Thus, the results suggest the establishment of selection indices aiming at simultaneously increasing the grain yield and earliness in sorghum genotypes.

Oral yeast colonization throughout pregnancy.

BACKGROUND: Recent studies suggest that placenta may harbour a unique microbiome that may have origin in maternal oral microbiome. Although the major physiological and hormonal adjustments observed in pregnant women lead to biochemical and microbiological modifications of the oral environment, very few studies evaluated the changes suffered by the oral microbiota throughout pregnancy. So, the aim of our study was to evaluate oral yeast colonization throughout pregnancy and to compare it with non-pregnant women. MATERIAL AND METHODS: The oral yeast colonization was assessed in saliva of 30 pregnant and non-pregnant women longitudinally over a 6-months period. Demographic information was collected, a non-invasive intra-oral examination was performed and saliva flow and pH were determined. RESULTS: Pregnant and non-pregnant groups were similar regarding age and level of education. Saliva flow rate did not differ, but saliva pH was lower in pregnant than in non-pregnant women. Oral yeast prevalence was higher in pregnant than in non-pregnant women, either in the first or in the third trimester, but did not attain statistical significance. In individuals colonized with yeast, the total yeast quantification (Log10CFU/mL) increase from the 1st to the 3rd trimester in pregnant women, but not in non-pregnant women. CONCLUSIONS: Pregnancy may favour oral yeast growth that may be associated with an acidic oral environment.

Gene expression of thyroid-specific transcription factors may help diagnose thyroid lesions but are not determinants of tumor progression.

PURPOSE: The role of thyroid-specific transcription factors in thyroid malignancy is still poorly understood, so we investigate thyroid-specific transcription factors gene expression both in benign and in malignant thyroid nodules, aiming to study a possible clinical utility of these molecules. METHODS: We quantified TTF-1, FOXE1 and PAX8 mRNA levels, relating their expression to diagnostic and prognostic features of thyroid tumors. RNA was extracted from 4 normal thyroid tissues, 101 malignant [99 papillary thyroid carcinomas (PTC) and 2 anaplastic thyroid carcinomas] and 99 benign thyroid lesion tissues [49 goiter and 50 follicular adenomas (FA)]. RESULTS: Levels of mRNA of both FOXE1 (P < 0.0001) and PAX8 (P < 0.0001) genes, but not TTF-1 (P = 0.7056), were higher in benign than in malignant thyroid lesions. FOXE1 was able to identify malignant nodules with 75.8 % sensitivity, 76.1 % specificity, 75.8 % positive predictive value, 76.1 % negative predictive value and 75.9 % accuracy. PAX8 was able to identify malignancy with 60.6 % sensitivity, 81.1 % specificity, 76.9 % positive predictive value, 66.4 % negative predictive value and 70.6 % accuracy. Both FOXE1 and PAX8 gene expression patterns were also able to differentiate FA from the follicular variant of PTC-FVPTC. However, the investigated gene expression was neither associated with any clinical feature of tumor aggressiveness nor associated with recurrence or survival. CONCLUSIONS: We suggest that FOXE1 and PAX8 gene expression patterns may help to diagnose thyroid nodules, identifying malignancy and characterizing follicular-patterned thyroid lesions, but are not determinants of thyroid tumor progression.

Influence of Skeletal Maturity on Size, Function and Sport-specific Technical Skills in Youth Soccer Players.

This study compared variation in size, function and sport-specific technical skills of youth soccer players associated with differences in biological maturity status. 60 male soccer players of under-14 (U14) and under-17 (U17) categories were submitted to anthropometric and body composition measurements as well as motor and soccer-specific technical skill tests. Skeletal maturity was determined by skeletal age. Athletes of both categories were classified as early, on-time or late-maturing, according to the difference between chronological age and skeletal age. Body mass and height were lower in the late athletes, independent of category (P<0.01). Differences in adiposity were found only between athletes of the U14 (late

Non-invasive mouse models of post-traumatic osteoarthritis.

Animal models of osteoarthritis (OA) are essential tools for investigating the development of the disease on a more rapid timeline than human OA. Mice are particularly useful due to the plethora of genetically modified or inbred mouse strains available. The majority of available mouse models of OA use a joint injury or other acute insult to initiate joint degeneration, representing post-traumatic osteoarthritis (PTOA). However, no consensus exists on which injury methods are most translatable to human OA. Currently, surgical injury methods are most commonly used for studies of OA in mice; however, these methods may have confounding effects due to the surgical/invasive injury procedure itself, rather than the targeted joint injury. Non-invasive injury methods avoid this complication by mechanically inducing a joint injury externally, without breaking the skin or disrupting the joint. In this regard, non-invasive injury models may be crucial for investigating early adaptive processes initiated at the time of injury, and may be more representative of human OA in which injury is induced mechanically. A small number of non-invasive mouse models of PTOA have been described within the last few years, including intra-articular fracture of tibial subchondral bone, cyclic tibial compression loading of articular cartilage, and anterior cruciate ligament (ACL) rupture via tibial compression overload. This review describes the methods used to induce joint injury in each of these non-invasive models, and presents the findings of studies utilizing these models. Altogether, these non-invasive mouse models represent a unique and important spectrum of animal models for studying different aspects of PTOA.

Longitudinal Development of Explosive Leg Power from Childhood to Adulthood in Soccer Players.

The aim of the this study was to investigate the development of explosive leg power by using 2 similar jumping protocols (countermovement jump and standing broad jump) in 555 Belgian, high-level young soccer players, aged between 7 and 20 years. The total sample was divided into 3 longitudinal samples related to growth and maturation (pre-teenchildhood: (6-10 years;), early adolescence: (11-16 years;) and late adolescence: (17-20 years)), and 6 multilevel regression models were obtained. Generally, both jumping protocols emphasized that chronological age, body size dimensions (by means of fat mass in the late childhood and early adolescence groups, fat-free mass in the late adolescence group and stature--(not for CMJ in late childhood group) and fat mass in the late childhood and early adolescence groups, and fat-free mass in the late adolescence group) and motor coordination (one item of a 3-component test battery) are longitudinal predictors of explosive leg power from childhood to young adulthood. The contribution of maturational status was not investigated in this study. The present findings highlight the importance of including non-specific motor coordination in soccer talent development programs.

Skeletal Maturation and Aerobic Performance in Young Soccer Players from Professional Academies.

The contribution of chronological age, skeletal age (Fels method) and body size to variance in peak velocity derived from the Carminatti Test was examined in 3 competitive age groups of Brazilian male soccer players: 10-11 years (U-12, n=15), 12-13 years (U-14, n=54) and 14-15 years (U-16, n=23). Body size and soccer-specific aerobic fitness were measured. Body composition was predicted from skinfolds. Analysis of variance and covariance (controlling for chronological age) were used to compare soccer players by age group and by skeletal maturity status within of each age group, respectively. Relative skeletal age (skeletal age minus chronological age), body size, estimated fat-free mass and performance on the Carminatti Test increased significantly with age. Carminatti Test performance did not differ among players of contrasting skeletal maturity status in the 3 age groups. Results of multiple linear regressions indicated fat mass (negative) and chronological age (positive) were significant predictors of peak velocity derived from the Carminatti Test, whereas skeletal age was not a significant predictor. In conclusion, the Carminatti Test appears to be a potentially interesting field protocol to assess intermittent endurance running capacity in youth soccer programs since it is independent of biological maturity status.

Peptides derived from phage display libraries as potential neutralizers of Shiga toxin-induced cytotoxicity in vitro and in vivo.

AIMS: To use the phage display technique to develop peptides with the capability to neutralize the cytotoxicity induced by Stx1 and Stx2 toxins produced by Shiga toxin-producing Escherichia coli (STEC). METHODS AND RESULTS: The phage display technique permitted the development of three peptides, named PC7-12, P12-26 and PC7-30, which bind to the globotriaosylceramide (Gb3) receptor for Shiga toxins produced by STEC. Moreover, these peptides were capable of competing efficiently with the Shiga toxins for binding to Gb3. The peptides described herein partially inhibited the Stx-induced cytotoxicity of cell-free filtrates of STEC O157 : H7 and purified Stx toxins in Vero cells. The inhibition of lethality induced by Stx toxins in mice indicated that peptide PC7-30 inhibited the lethality caused by Stx1 (2LD50) in mice. CONCLUSIONS: The phage display technique permitted the development of peptides that inhibited the cytotoxicity induced by Stx toxins in vitro. Peptide PC7-30 inhibited the lethality of Stx1 in vivo; this molecule would be a promising candidate for the development of therapeutic agents for STEC-related diseases in humans. SIGNIFICANCE AND IMPACT OF THE STUDY: The selection of Gb3, the common receptor for Stx1 and Stx2, may contribute to the development of efficient neutralizers for both toxins, and our approach would be an interesting alternative for the development of therapeutic molecules for the treatment of diseases caused by STEC strains.

Sport injuries aligned to peak height velocity in talented pubertal soccer players.

In young athletes, demands of sports are superimposed on normal growth and maturation. It has been suggested that this causes a temporarily increased vulnerability for injuries. We followed 26 talented soccer players (mean age 11.9±0.84 years) longitudinally for 3 years around their adolescent growth spurt, called Peak Height Velocity, to identify differences in number of traumatic and overuse injuries and days missed due to injuries. Peak Height Velocity was calculated according to the Maturity Offset Protocol. The number of injuries was calculated for each player per year. A repeated measurement analysis showed that athletes had significantly more traumatic injuries in the year of Peak Height Velocity (1.41) than in the year before Peak Height Velocity (0.81). A moderate effect size of 0.42 was found for the difference in number of overuse injuries per player per year before (0.81) and after Peak Height Velocity (1.41), respectively. Finally, a moderate effect size of 0.55 was found for difference between days missed due to injuries before (7.27 days per player per year) and during Peak Height Velocity (15.69 days per player per year). Adolescent growth spurt seems to result in increased vulnerability for traumatic injuries. Afterwards athletes seem to be susceptible to overuse injuries.

Allometric multilevel modelling of agility and dribbling speed by skeletal age and playing position in youth soccer players.

This study evaluates the contributions of age, skeletal maturation, body size and composition, training and playing position to the development of agility and dribbling speed in young male soccer players (10-18 years) followed longitudinally. 83 players [defenders (n=35), midfielders (n=27), forwards (n=21)] were followed annually over 5 years (average: 4.4 observations per player). Skeletal age (SA), stature, body mass, triceps and subscapular skinfolds, agility and dribbling speed were measured annually. Body composition was estimated from the 2 skinfolds. Annual training volume was estimated from weekly participation forms completed by coaches. The multiplicative allometric models with the best statistical fit showed that statural growth of 1 cm predicts 1.334 s and 1.927 s of improvement in agility and dribbling speed, respectively. Significant independent effects of fat-free mass and annual volume training were found for agility and dribbling speed, respectively (P<0.05). Predicted agility (from 12 to 18 years of SA) and dribbling speed (from 13 to 18 years of SA) differed significantly among players by playing positions (midfielders>forwards>defenders). The present results provide developmental models for the interpretation of intra- and inter-individual variability in agility and dribbling speed among youth soccer players across adolescence, and may provide a framework for trainers and coaches to develop and evaluate individualized training protocols.

Maturity-associated variation in change of direction and dribbling speed in early pubertal years and 5-year developmental changes in young soccer players.

AIM: The purpose of the current study was to assess the developmental changes in change of direction and dribbling speed in youth soccer players taking into account skeletal age (SA), maturity status, body size, estimated fat mass, aerobic endurance, lower limb explosive strength and annual volume of training. METHODS: Eighty-three male soccer players aged 10-15 years (SA) at baseline were annually followed over 5 years, resulting in an average 4.4 observations per player. After testing for multicollinearity, multi-level regression modeling was used to examine the longitudinal developmental changes on change of direction and dribbling speed. RESULTS: Maturity-associated variability was significant in change of direction and also dribbling speed among young soccer players aged 12-14 years with better scores being performed by late maturers. Moreover, the predicted longitudinal scores for change of direction and dribbling speed improved with SA (P<0.01), SA2 (P<0.01) and skeletal maturity status entered as an additional developmental predictor (P<0.05). Estimated fat-free mass (P<0.01), aerobic endurance (P<0.01) and lower limb strength (P<0.01) were additional predictors in both models. The soccer-specific skill, dibbling speed, was also explained by annual volume of training (P<0.05). CONCLUSION: Skeletal maturity status explains inter-individual variability on maximal short-term run performances with and without the ball possession at early ages of participation in competitive soccer. The effects tend to persist across ages combined with longitudinal changes in body composition and functional fitness. In the particular case of the ball test, annual volume of training was also a longitudinal performance predictor.

Anthropometric characteristics, physical fitness and technical performance of under-19 soccer players by competitive level and field position.

Anthropometric characteristics, physical fitness and technical skills of under-19 (U19) soccer players were compared by competitive level (elite, n=95; non-elite, n=85) and playing position (goalkeeper, central defender, fullback, midfield, forward). Fitness tests included 5- and 30-m sprints, agility, squat jump (SJ) and countermovement jump (CMJ), strength and Yo-Yo intermittent endurance test level 2 (Yo-Yo IE2). Soccer-specific skills included ball control and dribbling. Independent of position, elite players presented more hours of training per year than non-elite players (d>1.2). Stature and body mass discriminated elite from non-elite players among goalkeepers and central defenders (d>0.6). Major differences were noted between elite and non-elite goalkeepers for SJ, CMJ, Yo-Yo IE2, and ball control (d>1.2). Elite central defenders performed better than their non-elite counterparts in SJ and ball control tests (d>1.2). Elite players presented better agility and Yo-Yo IE2 performances than non-elite players within all positional roles (d>0.6). In conclusion, U19 players differed in anthropometric characteristics, physical fitness and technical skills by competitive level within field positions.

Changes in skeletal muscle mass assessed by anthropometric equations after resistance training.

The aim of this study was to analyze the validity of anthropometric equations to identify changes in skeletal muscle mass (SMM) after resistance training (RT). Anthropometric and dual energy x-ray absorptiometry (DXA) measurements were obtained at baseline and after RT in 15 trained Caucasian college men. Participants performed RT over 8 weeks, consisting of 8-9 exercises of 4 sets with 12/10/8/6 maximal repetitions and 1-2 min interval between sets. The training loads were gradually increased according to gains in muscular strength. 4 anthropometric equations were used for estimation of SMM: EQ1 (SMM, g=height×[0.0553×corrected thigh girth2 + 0.0987×forearm girth2 + 0.0331×corrected calf girth2] - 2445), EQ2 (SMM, g=height×[0.031×medial thigh girth2 + 0.064×corrected calf girth2 + 0.089×corrected arm girth2] - 3006), EQ3 (SMM, kg=height×[0.00744×corrected arm girth2 + 0.00088×corrected thigh girth2 + 0.00441×corrected calf girth2] + 2.4×gender - 0.048×age + race + 7.8) and EQ4 (SMM, kg=0.244×weight + 7.8×height + 6.6×gender - 0.098×age + race - 3.3). EQ1 and EQ2 overestimated the SMM (41.3% and 19.9%, respectively; P<0.05) while EQ3 and EQ4 were similar (P>0.05) to DXA at baseline. Although all equations and DXA revealed a significant increase in SMM after RT, changes were overestimated by EQ1 and EQ2 (P<0.05), but not by EQ3 and EQ4 (P>0.05). In addition, changes in SMM over time between EQ4 and DXA were significantly correlated (r=0.62; P<0.01). Thus, changes in SMM that occur after RT can be detected by EQ4 in trained young men.