Calcifediol is a safe and effective metabolite for raising vitamin D status and improving growth and feed conversion in rainbow trout

The vitamin D endocrine system is required for the transcriptional regulation of a myriad of vertebrate genes including those involved in bone health, growth, nutrient metabolism and immunity. The requirements of salmonids for vitamin D are amongst the highest for any aquaculture species. With nuances, the metabolism of the pre-vitamin cholecalciferol (D3) via calcifediol (25-OH-D3), required to produce the physiologically active hormone calcitriol (1,25-OH-D3) is conserved in fish. The composition of modern aquafeeds, growth in seawater and production challenges, such as disease, may result in the suboptimal biochemical activation of vitamin D hormone in fish. A 91-day experimental feeding trial was used to test the safety and efficacy of calcifediol for the supply of vitamin D to rainbow trout with an initial body weight of 57.6 g. A practical diet containing cholecalciferol within recommended levels (5240 IU) was supplemented with either 69.8, 687 or 6854 μg/kg calcifediol. The efficacy of calcifediol was determined by the assessment of zootechnical performance and the appearance of vitamin D metabolites in the blood. The safety of the dietary interventions was assessed from generic health indices, examination of gross pathologies, hematology, and blood chemistry. Test fish increased body weight at least 5.6-fold to 323.5 g over the experimental feeding period. The supplementation of 687 or 6854 μg/kg calcifediol resulted in significant improvements in growth rate and feed conversion (FCR). Whilst not detectable in control fish, calcifediol increased linearly according to dietary levels in the blood and to a lesser extent in the white muscle. The increases of calcifediol in the blood were accompanied by saturable increases of circulating active vitamin D. At the end of the 91-day feeding period, survival was 100%, no gross pathologies relating to the diets were observed, and health indices, hematology, and blood chemistry, including calcium and phosphorus, were not significantly altered. The supplementation of calcifediol to practical diets containing recommended levels of cholecalciferol improves zootechnical performance and ensures that maximal levels of active vitamin D are present in the blood to meet physiological demands. With a lack of significant effects on health indices, hematology, and blood chemistry, including calcium and phosphorus, the tested high doses of calcifediol are concluded to be safe for salmonids

Meiotic Regulation of TPX2 Protein Levels Governs Cell Cycle Progression in Mouse Oocytes

Formation of female gametes requires acentriolar spindle assembly during meiosis. Mitotic spindles organize from centrosomes and via local activation of the RanGTPase on chromosomes. Vertebrate oocytes present a RanGTP gradient centred on chromatin at all stages of meiotic maturation. However, this gradient is dispensable for assembly of the first meiotic spindle. To understand this meiosis I peculiarity, we studied TPX2, a Ran target, in mouse oocytes. Strikingly, TPX2 activity is controlled at the protein level through its accumulation from meiosis I to II. By RNAi depletion and live imaging, we show that TPX2 is required for spindle assembly via two distinct functions. It controls microtubule assembly and spindle pole integrity via the phosphorylation of TACC3, a regulator of MTOCs activity. We show that meiotic spindle formation in vivo depends on the regulation of at least a target of Ran, TPX2, rather than on the regulation of the RanGTP gradient itself

Circulating adrenomedullin estimates survival and reversibility of organ failure in sepsis: the prospective observational multinational Adrenomedullin and Outcome in Sepsis and Septic Shock-1 (AdrenOSS-1) study

Background: Adrenomedullin (ADM) regulates vascular tone and endothelial permeability during sepsis. Levels of circulating biologically active ADM (bio-ADM) show an inverse relationship with blood pressure and a direct relationship with vasopressor requirement. In the present prospective observational multinational Adrenomedullin and Outcome in Sepsis and Septic Shock 1 (, AdrenOSS-1) study, we assessed relationships between circulating bio-ADM during the initial intensive care unit (ICU) stay and short-term outcome in order to eventually design a biomarker-guided randomized controlled trial. Methods: AdrenOSS-1 was a prospective observational multinational study. The primary outcome was 28-day mortality. Secondary outcomes included organ failure as defined by Sequential Organ Failure Assessment (SOFA) score, organ support with focus on vasopressor/inotropic use, and need for renal replacement therapy. AdrenOSS-1 included 583 patients admitted to the ICU with sepsis or septic shock. Results: Circulating bio-ADM levels were measured upon admission and at day 2. Median bio-ADM concentration upon admission was 80.5 pg/ml [IQR 41.5-148.1 pg/ml]. Initial SOFA score was 7 [IQR 5-10], and 28-day mortality was 22%. We found marked associations between bio-ADM upon admission and 28-day mortality (unadjusted standardized HR 2.3 [CI 1.9-2.9]; adjusted HR 1.6 [CI 1.1-2.5]) and between bio-ADM levels and SOFA score (p < 0.0001). Need of vasopressor/inotrope, renal replacement therapy, and positive fluid balance were more prevalent in patients with a bio-ADM > 70 pg/ml upon admission than in those with bio-ADM ≤ 70 pg/ml. In patients with bio-ADM > 70 pg/ml upon admission, decrease in bio-ADM below 70 pg/ml at day 2 was associated with recovery of organ function at day 7 and better 28-day outcome (9.5% mortality). By contrast, persistently elevated bio-ADM at day 2 was associated with prolonged organ dysfunction and high 28-day mortality (38.1% mortality, HR 4.9, 95% CI 2.5-9.8). Conclusions: AdrenOSS-1 shows that early levels and rapid changes in bio-ADM estimate short-term outcome in sepsis and septic shock. These data are the backbone of the design of the biomarker-guided AdrenOSS-2 trial. Trial registration: ClinicalTrials.gov, NCT02393781. Registered on March 19, 2015

ACTRIS ACSM intercomparison – Part 1: Reproducibility of concentration and fragment results from 13 individual Quadrupole Aerosol Chemical Speciation Monitors (Q-ACSM) and consistency with co-located instruments

As part of the European ACTRIS project, the first large Quadrupole Aerosol Chemical Speciation Monitor (Q-ACSM) intercomparison study was conducted in the region of Paris for 3 weeks during the late-fall – early-winter period (November–December 2013). The first week was dedicated to the tuning and calibration of each instrument, whereas the second and third were dedicated to side-by-side comparison in ambient conditions with co-located instruments providing independent information on submicron aerosol optical, physical, and chemical properties. Near real-time measurements of the major chemical species (organic matter, sulfate, nitrate, ammonium, and chloride) in the non-refractory submicron aerosols (NR-PM1) were obtained here from 13 Q-ACSM. The results show that these instruments can produce highly comparable and robust measurements of the NR-PM1 total mass and its major components. Taking the median of the 13 Q-ACSM as a reference for this study, strong correlations (r2 > 0.9) were observed systematically for each individual Q-ACSM across all chemical families except for chloride for which three Q-ACSMs showing weak correlations partly due to the very low concentrations during the study. Reproducibility expanded uncertainties of Q-ACSM concentration measurements were determined using appropriate methodologies defined by the International Standard Organization (ISO 17025, 1999) and were found to be 9, 15, 19, 28, and 36 % for NR-PM1, nitrate, organic matter, sulfate, and ammonium, respectively. However, discrepancies were observed in the relative concentrations of the constituent mass fragments for each chemical component. In particular, significant differences were observed for the organic fragment at mass-to-charge ratio 44, which is a key parameter describing the oxidation state of organic aerosol. Following this first major intercomparison exercise of a large number of Q-ACSMs, detailed intercomparison results are presented, along with a discussion of some recommendations about best calibration practices, standardized data processing, and data treatment.JRC.H.2-Air and Climat

MAPK-Activated Protein Kinase 2 Is Required for Mouse Meiotic Spindle Assembly and Kinetochore-Microtubule Attachment

MAPK-activated protein kinase 2 (MK2), a direct substrate of p38 MAPK, plays key roles in multiple physiological functions in mitosis. Here, we show for the first time the unique distribution pattern of MK2 in meiosis. Phospho-MK2 was localized on bipolar spindle minus ends and along the interstitial axes of homologous chromosomes extending over centromere regions and arm regions at metaphase of first meiosis (MI stage) in mouse oocytes. At metaphase of second meiosis (MII stage), p-MK2 was localized on the bipolar spindle minus ends and at the inner centromere region of sister chromatids as dots. Knockdown or inhibition of MK2 resulted in spindle defects. Spindles were surrounded by irregular nondisjunction chromosomes, which were arranged in an amphitelic or syntelic/monotelic manner, or chromosomes detached from the spindles. Kinetochore–microtubule attachments were impaired in MK2-deficient oocytes because spindle microtubules became unstable in response to cold treatment. In addition, homologous chromosome segregation and meiosis progression were inhibited in these oocytes. Our data suggest that MK2 may be essential for functional meiotic bipolar spindle formation, chromosome segregation and proper kinetochore–microtubule attachments

ALADIN is Required for the Production of Fertile Mouse Oocytes

Asymmetric cell divisions depend on the precise placement of the spindle apparatus. In mammalian oocytes, spindles assemble close to the cell's center, but chromosome segregation takes place at the cell periphery where half of the chromosomes are expelled into small, nondeveloping polar bodies at anaphase. By dividing so asymmetrically, most of the cytoplasmic content within the oocyte is preserved, which is critical for successful fertilization and early development. Recently we determined that the nucleoporin ALADIN participates in spindle assembly in somatic cells, and we have also shown that female mice homozygously null for ALADIN are sterile. In this study we show that this protein is involved in specific meiotic stages, including meiotic resumption, spindle assembly, and spindle positioning. In the absence of ALADIN, polar body extrusion is compromised due to problems in spindle orientation and anchoring at the first meiotic anaphase. ALADIN null oocytes that mature far enough to be fertilized in vitro are unable to support embryonic development beyond the two-cell stage. Overall, we find that ALADIN is critical for oocyte maturation and appears to be far more essential for this process than for somatic cell divisions

Challenges and Opportunities in Finfish Nutrition

Much of the criticism leveled at aquaculture (e.g., dependency on animal-derived feedstuffs, nutrient-laden effluent discharges, and increased organic contamination in edible products) can be traced to the feeds in use. Accordingly, finfish nutritionists are being challenged to formulate feeds that not only meet the nutritional requirements of livestock but also minimize production costs, limit environmental impacts, and enhance product quality. These challenges not only add considerable complexity to finfish nutrition but also afford opportunities to avoid some of the mistakes made by other industries in the past. From a review of the current status of finfish nutrition with respect to major nutrient classes, we comment on future opportunities and promising avenues of research. Alternative protein sources, specifically those derived from marine bycatch, plants, and microbes, are discussed, as well as methods to facilitate their implementation in finfish feeds. Dietary lipid, its role in fish bioenergetics and physiology, and quality of aquaculture products is reviewed with special emphasis on alternative lipid sources and finishing diets. Carbohydrates and fiber are discussed in terms of nutrient-sparing, least-cost diet formulation and digestive physiology. Micronutrients are reviewed in terms of current knowledge of requirements and, along with other dietary immunostimulants, are given further consideration in a review of nutriceuticals and application in finfish feeds. The status of nutritional research in new aquaculture species is also outlined. By integrating classical approaches with emerging technologies, dietary formulations, and species, finfish nutritionists may identify means to increase production efficiency and sustainability and provide for the continued success of aquaculture

ACTRIS ACSM intercomparison - Part 1 : Reproducibility of concentration and fragment results from 13 individual Quadrupole Aerosol Chemical Speciation Monitors (Q-ACSM) and consistency with co-located instruments

As part of the European ACTRIS project, the first large Quadrupole Aerosol Chemical Speciation Monitor (Q-ACSM) intercomparison study was conducted in the region of Paris for 3 weeks during the late-fall-early-winter period (November-December 2013). The first week was dedicated to the tuning and calibration of each instrument, whereas the second and third were dedicated to side-by-side comparison in ambient conditions with co-located instruments providing independent information on submicron aerosol optical, physical, and chemical properties. Near real-time measurements of the major chemical species (organic matter, sulfate, nitrate, ammonium, and chloride) in the non-refractory submicron aerosols (NR-PM1) were obtained here from 13 Q-ACSM. The results show that these instruments can produce highly comparable and robust measurements of the NR-PM1 total mass and its major components. Taking the median of the 13 Q-ACSM as a reference for this study, strong correlations (r(2) > 0.9) were observed systematically for each individual Q-ACSM across all chemical families except for chloride for which three Q-ACSMs showing weak correlations partly due to the very low concentrations during the study. Reproducibility expanded uncertainties of Q-ACSM concentration measurements were determined using appropriate methodologies defined by the International Standard Organization (ISO 17025, 1999) and were found to be 9, 15, 19, 28, and 36% for NR-PM1, nitrate, organic matter, sulfate, and ammonium, respectively. However, discrepancies were observed in the relative concentrations of the constituent mass fragments for each chemical component. In particular, significant differences were observed for the organic fragment at mass-to-charge ratio 44, which is a key parameter describing the oxidation state of organic aerosol. Following this first major intercomparison exercise of a large number of Q-ACSMs, detailed intercomparison results are presented, along with a discussion of some recommendations about best calibration practices, standardized data processing, and data treatment.Peer reviewe