Taurine is a sulfonic acid found in high concentrations in animal tissues. In recent years, a number of studies have demonstrated the essentiality of dietary taurine for many commercially relevant ...species, especially marine teleosts. Consequently, the removal of taurine-rich dietary ingredients such as fishmeal may create a deficiency, of which symptoms include reduced growth and survival, increased susceptibility to diseases, and impaired larval development. These symptoms emphasize the systemic role of taurine in the animal’s physiology and provide few clues as to the underlying mechanisms of taurine function. In fact, a myriad of roles have been attributed to taurine in mammals, ranging from bile salt conjugation to membrane stabilization, osmoregulation, anti-oxidation, immunomodulation, calcium-signaling, and neuroprotection. This review describes the current knowledge of taurine physiology and metabolism in fish and requirement levels in relevant species, and highlights possible parallels with mammalian taurine metabolism. In addition, the effects of ingredient processing and feed manufacturing on taurine bioavailability are discussed. Finally, regulatory aspects are brought to the forefront: although the supplementation of taurine will be necessary to further reduce the use of ingredients such as fishmeal, taurine is not currently approved by the FDA in the USA for fish feeds. Obtaining approval in the United States to utilize taurine in fish feeds can improve the environmental and economic sustainability of fish feeds nation-wide.
•In susceptible species, dietary taurine must be supplemented when using taurine-poor ingredients in feeds.•However, taurine is currently not listed as an approved ingredient for animal feeds in the USA.•Taurine is involved in bile salt formation, membrane stability, immunomodulation, anti-oxidation and mitochondrial function, and calcium-signaling.•The roles of taurine and its mechanisms in fish remain poorly described.
Many studies aim at identifying environmental correlates of walking in order to identify specific potential levers for tackling the medical burden of physical inactivity. The links between ...environmental characteristics and walking behaviors are usually context specific. While local studies fail to embrace a global overview of these contexts, global studies hide the context scale patterns. In this study, we applied a geographically weighted logistic regression (GWR) on a large area (whole of France) to explore spatial variations of the relations between five environmental variables and walking for leisure and errands purposes among 40,480 French adults. This approach allowed us to adopt a global view of local patterns of relations and to highlight spatial contexts (defined through a clustering of GWR odds ratios) where combinations of correlates varied. Specifically, clustering algorithms on the GWR odds ratios led to 9 and 6 clusters for walking for leisure and errands, respectively. Some clusters were characterized by a particularly strong effect of population density, whereas others exhibited low effect of vegetation cover rate. Chi-squared tests indicated that these clusters were associated with type of urban areas (Paris, major urban poles, periurban areas, small urban poles, isolated areas) for the two types of walking. Beyond its methodological contribution - providing a method to handle large data samples into GWR analyses - this study offers key elements to practitioners and policy makers to target relevant contexts and environmental features for promoting daily walking.
Some characteristics of the built environment have been associated with obesity in youth. Our aim was to determine whether individual and environmental socio-economic characteristics modulate the ...relation between youth overweight and spatial accessibility to physical activity (PA) facilities and to food outlets.
Cross-sectional study.
3293 students, aged 12 ± 0.6 years, randomly selected from eastern France middle schools.
Using geographical information systems (GIS), spatial accessibility to PA facilities (urban and nature) was assessed using the distance to PA facilities at the municipality level; spatial accessibility to food outlets (general food outlets, bakeries and fast-food outlets) was calculated at individual level using the student home address and the food outlets addresses. Relations of weight status with spatial accessibility to PA facilities and to food outlets were analysed using mixed logistic models, testing potential direct and interaction effects of individual and environmental socio-economic characteristics.
Individual socio-economic status modulated the relation between spatial accessibility to PA facilities and to general food outlets and overweight. The likelihood of being overweight was higher when spatial accessibility to urban PA facilities and to general food outlets was low, but in children of blue-collar-workers only. The odds ratio (OR) (95% confidence interval) for being overweight of blue-collar-workers children compared with non-blue-collar-workers children was 1.76 (1.25-2.49) when spatial accessibility to urban PA facilities was low. This OR was 1.86 (1.20-2.86) when spatial accessibility to general food outlets was low. There was no significant relationship of overweight with either nature PA facilities or other food outlets (bakeries and fast-food outlets).
These results indicate that disparities in spatial accessibility to PA facilities and to general food outlets may amplify the risk of overweight in socio-economically disadvantaged youth. These data should be relevant for influencing health policies and urban planning at both a national and local level.
Florida pompano Trachinotus carolinus is an important species in which the essentiality of taurine has been demonstrated, yet a quantitative requirement has not been estimated. Two experiments were ...conducted where a combined twelve diets were formulated with graded levels of taurine (ranging 1.6–41.6 g/kg dry matter) and fed to juvenile pompano (initial weight 7.73 and 4.37 g in trial 1 and 2, respectively). Dose responses were observed in terms of growth, feed efficiency and whole‐body taurine content, but there was no effect on survival. Several regression models were evaluated to determine the most appropriate one to draw conclusions from. A 4‐parameter saturation kinetic model was selected to model feed efficiency, while a 5‐parameter saturation kinetic model fitted the growth data (as thermal‐unit growth coefficient, TGC). A broken‐quadratic model served to estimate a breaking point in the whole‐body taurine content, although it also showed that whole‐body taurine kept increasing even at dietary levels in far excess of the requirement. The dietary taurine requirement was estimated at 2.5 g/kg (2.0–3.3 g/kg, 95% CI, dry matter basis) based on feed efficiency, while TGC was maximized at levels between 4.9 and 31.4 g/kg dietary taurine.
Two growth trials were designed to evaluate varying levels of taurine in diets for white seabass (WSB), Atractoscion nobilis. All diets were formulated to contain 40% protein and 10% lipid with a ...fixed level of fish meal (FM) and soybean meal (SBM). Trial A tested a series of six practical diets with 0.0, 0.1, 0.2, 0.3, 0.4, 0.5% taurine supplementation at the expense of glutamic acid, and a seventh diet with 0.5% cystine supplementation instead of taurine. Trial B was designed to test higher inclusion levels (0.2-1.6%) of taurine over six diets, while a seventh diet contained 1.6% taurine but no methionine supplement. In Trial A, the increased inclusion of taurine resulted in significantly improved final weight ranging from 14.6 to 26.6 g, TGC ranging from 0.074 to 0.120, and feed efficiency from 68.2 to 111.9%. The supplementation of cystine to the diet did not result in an improvement in growth, indicating the synthesis of taurine from cysteine decarboxylation is inadequate in WSB. Similarly, in Trial B significant improvements in performance were observed with increasing taurine supplements, albeit variation in the data was higher. Final weight ranged from 23.6 to 29.7 g, TGC ranging from 0.111 to 0.130 and feed efficiency from 75.6 to 81.4%. The diet with taurine supplement but without methionine showed a decrease in growth, suggesting that methionine was then limiting. Datasets from both trials were combined, and a saturation kinetics model was used to determine a dietary requirement of 0.99% of the diet (R2 = 0.8770). Based on these results, white seabass have a dietary requirement for taurine presumably due to a limited ability to synthesize it. PUBLICATION ABSTRACT
Despite garnering high interest in fish nutrition as an essential amino acid in a number of teleosts, the metabolic and physiological functions of taurine remain poorly described in fish. This study ...describes the postprandial changes of taurine in Florida pompano juveniles fed a taurine-replete diet, followed by a wide screening of metabolic and physiological markers when fed a taurine-deficient diet over 16days. The goal was to screen for markers of early taurine deficiency and identify its initial components. Postprandial taurine levels varied between 106.75 and 170.37μg/ml with a mild peak at 2–4h after feeding, and decreased to 72.1% of the baseline value at 6h. Fish fed the taurine-deficient diet did not have reduced hematocrit or increased bilirubin, suggesting an absence of hemolysis. However, linear decreases in alkaline phosphatase activity and in bile acid content were observed (R2=0.5968 and 0.5613, respectively, P<0.005). Filet composition showed an overall linear increase in moisture (R2=0.2666, P=0.0338) and a marked, linear loss in lipid over time (R2=0.4059, P=0.0059). There was also a drastic, quadratic decrease in all amino acid content of the liver (R2>0.75, P<0.0001), which had decreased by 40% by day 16. Notably, levels of taurine, hydroxylysine and hydroxyproline sharply decreased and remained low. In the filet however, levels of most amino acids were not affected, except for hydroxyproline, hydroxylysine, proline, and glycine, whose levels increased significantly by day 16 while taurine levels had decreased. Serum levels were variable, and no pattern of change could be identified. Liver histology revealed marked vacuolation of hepatocytes and significant glycogen accumulation. Finally, hepatic mitochondrial proteins quadratically decreased with time (R2=0.6218, P=0.0007), paralleled with a severe linear decrease in cytochrome c oxidase (COX) specific activity (R2=0.5940, P=0.0002). This indicates that the mitochondrial electron transport chain was greatly disrupted, and which resulted in poor hepatic metabolism and production of oxidative radicals. In summary, the present study describes the first screening for metabolic and physiological biomarkers of early taurine deficiency. Although we found no evidence of overt hepatocellular damage during the course of the experiment, we observed significant alterations of cellular metabolism, especially in hepatocytes (i.e., histology, amino acid content, COX activity). Changes in serum parameters were detected, although their suitability as biomarkers will require additional research. The absence of hematocrit decrease is noteworthy in light of published literature; longer term investigations are necessary to further our understanding of taurine functions in teleosts.
This manuscript presents results of scientific research relevant to the field of aquaculture. Taurine is a nutrient of great importance for many teleost species and for the sustainability of fish feeds; yet its metabolic functions remain unclear. This study constitutes, to the authors' knowledge, the first attempt at characterizing these functions. These results shed light on the complexities of taurine metabolism and emphasize possible hypotheses for future research. Therefore this study presents novel research results of high interest to the aquaculture and fish biology communities.
•Florida pompano fed a taurine-deficient diet were screened for biomarkers characterizing early taurine deficiency•There was no changes in hematocrit during the trial•The liver was the most impacted organ and changes were detectable by day 4 after switching to the deficient diet•Notable changes included marked vacuolation and drop in cytochrome c oxidase activity•Patterns of change in amino acid content were tissue-specific, and some amino acids deviated from the overall pattern.
Bone metastases cause pain and affect patients' quality of life. Radiation therapy is one of the reference analgesic treatments. The objective of this study was to compare the current practices of a ...French radiotherapy department for the treatment of uncomplicated bone metastases with data from the literature in order to improve and optimize the management of patients.
A retrospective monocentric study of patients who underwent palliative irradiation of uncomplicated bone metastases was performed.
Ninety-one patients had 116 treatments of uncomplicated bone metastases between January 2014 and December 2015, including 44 men (48%) and 47 women (52%) with an average age of 63years (25-88years). Primary tumours most commonly found were breast cancer (35%), lung cancer (16%) and prostate cancer (12%). The regimens used were in 29% of cases 30Gy in ten fractions (group 30Gy), in 21% of cases 20Gy in five fractions (group 20Gy), in 22% of cases 8Gy in one fraction (group 8Gy) and in 28% of cases 23.31Gy in three fractions of stereotactic body irradiation (stereotactic group). The general condition of the patient (P<0.001), pain score and analgesic (P<0.001), oligometastatic profile (P=0.003) and practitioner experience (P<0.001) were factors influencing the choice of the regimen irradiation. Age (P=0.46), sex (P=0.14), anticancer treatments (P=0.56), concomitant hospitalization (P=0.14) and the distance between the radiotherapy centre and home (P=0.87) did not influence the decision significantly. A total of three cases of spinal compression and one case of post-therapeutic fracture were observed, occurring between one and 128days and 577days after irradiation, respectively. Eight percent of all irradiated metastases were reirradiated with a delay ranging between 13 and 434days after the first irradiation. The re-irradiation rate was significantly higher after 8Gy (P=0.02). The rate of death was significantly lower in the stereotactic arm (P<0.001) and overall survival was significantly greater in the stereotactic arm (P<0.001).
This study showed that patients' analysed was comparable to the population of different studies. Predictive factors for the choice of the treatment regimen were identified. Non-fractionnated therapy was underutilised while stereotactic treatment was increasingly prescribed, showing an evolution in the management of patients.
To identify leisure-time physical activity (LTPA) and sedentary behavior patterns, as well as to investigate their relationships with overweight.
Cross-sectional study.
Men (n=2206) and women ...(n=2476) aged >45 years, living in France, enrolled in the SU.VI.MAX (Supplémentation en VItamines et Minéraux AntioXydants) study.
LTPA and sedentary behavior were assessed using the Modifiable Activity Questionnaire whereas weight and height were measured from study participants. Clusters were defined, by gender, with multiple correspondence analysis and cluster analysis successively, taking into account the type (walking, gardening, etc.) and duration of each physical activity performed, as well as the time spent watching television (TV) as typical sedentary behavior. Logistic regression models were used to assess associations with overweight.
Four physical activity and sedentary behavior clusters were identified among men and three among women. We chose as referent cluster the cluster associating 'walking and gardening-low TV' in men and the cluster associating 'walking and gardening-high TV' in women. Compared with the referent cluster and after adjustment for age, education level, smoking status and place of residence, the likelihood of overweight (defined as body mass index >or=25 kg m(-2)) in women was lower for a 'multiple activity-low TV' cluster (odds ratio (OR)=0.66, 95% confidence interval=0.54-0.81) and for a cluster associating 'endurance physical activity-low TV' (OR=0.42 (0.29-0.60)). Compared with the referent cluster and after adjustment, the likelihood of overweight in men was decreased for the 'endurance physical activity' cluster (OR=0.66, (0.52-0.84)), whereas no significant association was found with the other clusters.
Patterns combining specific types of physical activity and sedentary behavior were identified and differed in their relations to overweight in adults. The identification of global patterns of activity allows us to go beyond a simple decreased activity-increased body weight approach and adds to our understanding of the associations of specific forms and grouping of activity with overweight in adults.
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