110 research outputs found
Impact of anesthesia on some of physiological parameters in Acipenser nudiventris
Impact of anesthesia with electric shock on some of physiological parameters was studied in in Acipenser nudiventris in this study, we investigated the induction and recovery times and physiological response of Acipenser nudiventris. We anesthetized them by CO2 (mmhg), clove powder (mg/L), and electric shock (V). Shortest and longest induction time were 0.15 min and 4.25 min when electric shock and clove powder were used. On the other hand, shortest and longest time of recovery time were 3.23 min and 2. 20 min respectively when electric shock and CO2 gas were used. Cortisol and glucose levels increased 1 and 6 hours after anesthesia. Changes in plasma osmolality were less among the anesthesia treatments. Results demonstrated that electric shock was a more effective method for quick induction time, although all anesthetic methods were found to be safe
Le Cortisol et la DHEA comme marqueurs de la placentite chez la jument gestante : une étude préliminaire
peer reviewedPlacentitis in mares is a subclinical cause of abortion, high- lighting the importance of early detection for successful treatment. Sexual steroids could serve as biomarkers, but cross-reactivity and a limited detection range of immunoassays may hinder ac- curate measures. This study evaluated some steroids as poten- tial markers of placentitis using liquid chromatography coupled to mass spectrometry (LC-MS), known to improve detection and quantification of steroids with good selectivity, specificity, and allowing multiplexing capabilities (Conley et al., Reproduction. 2019;158:197-208; Ledeck et al., Theriogenology. 2022;189:86- 91). From the 7th month of pregnancy, mares were transrectally scanned to measure the combined thickness of the uterus and placenta (CTUP), and blood samples were collected at a fixed time of day. Ten healthy mares (HM) and nine mares diagnosed with non-experimentally-induced placentitis (PM) between 8 and 10 months were enrolled, based on ultrasonographic placentitis signs: heterogeneous echogenicity and/or thickened CTUP. Post- partum allantochorion examination confirmed the diagnosis. Sub- sequently, PM were further excluded from the study as they re- ceived treatments for placentitis. Serum concentrations of pro- gesterone, 17α-hydroxyprogesterone (17αOHP), dehydroepiandros- terone (DHEA), and cortisol were assayed using LC-MS. Non- normally distributed data were presented as medians, and groups were compared at the same month of pregnancy using the Mann- Whitney test. There were no significant differences in 17αOHP and progesterone concentrations between groups at any month.
DHEA concentrations were significantly higher (p=0.0297) at 8 months in PM (3.552μg/L) compared to HM (2.240μg/L). A sim- ilar trend was observed at 9 months, with DHEA concentra- tions of 2.126μg/L and 1.445μg/L in PM and HM, respectively (p=0.0604). In contrast, HM had significantly higher (p=0.022) cortisol concentrations at 7 months (71.75μg/L) compared to PM (38.62μg/L). This difference tended (p=0.0529) to be observed at 8 months with cortisol concentrations of 52.25μg/L (HM) and 37.28μg/L (PM). The DHEA/cortisol ratio was significantly higher in PM than in HM at 9 months (p=0.013) and tended to be in- creased at 7 and 8 months (respectively, p=0.0659 and p=0.0529). Placentitis has been shown to increase pregnenolone production (Ousey et al., Theriogenology. 2005;63:1844-1856). In this prelim- inary study, PM were observed to metabolize pregnenolone into DHEA rather than cortisol, without changes in 17αOHP concen- trations. Reduced cortisol concentrations at 7 months could be an early but non-specific biomarker of placentitis. Conversely, elevated DHEA Ievels only appear together with ultrasonographic signs at 8 months but could become a more specific biomarker, which dif- fers from previous findings in mares with experimentally-induced placentitis (Canisso et al., Equine Veterinary Journal. 2017;49:244- 249). These changes result in a higher DHEA/cortisol ratio in PM at 9 months. However, further research should explore mod- ifications of steroids’ pathways in PM to confirm the value of DHEA and cortisol for early diagnosis of placentitis in mares.Study of equine placental sexual steroids’ metabolism using Mass Spectrometry (LC-MS/MS) and in vitro model to develop early diagnosis methods of placental pathologie
Development and validation of a liquid chromatography coupled to mass spectrometer (LC-MS) method for the simultaneous quantification of estrone-3-sulfate, progesterone, estrone and estradiol in serum of mares and American bisons
peer reviewedSteroid concentrations in serum are fluctuating during pregnancy of many mammal species. The current
knowledge about endocrinology of gestation is mainly based on immunoassays. However, the lack of specificity
of these assays hampers the reliability of the results. In the present work, we developed and validated a methodology associating liquid chromatography (LC) and mass spectrometry (MS) to simultaneously quantify, with
high specificity and accuracy, estrone-3-sulfate (E3S), progesterone (PRO), estrone (E1) and estradiol (E2) in
serum of two different mammal species.
The sample preparation procedure is based on a simple protein precipitation and a derivatization with dansyl
chloride. After the chromatographical separation, compounds were analyzed with a triple-quadrupole mass
spectrometer operating in multiple reaction monitoring. Mare and American bison serum samples were analyzed
with the validated method and results were compared with concentrations measured with commercial radioimmunoassay (RIA), enzyme linked immunosorbent assay (ELISA) and chemiluminescent microparticle immunoassay (CMIA).
Following these criterions: relative standard deviation <15% and relative bias <15%, lower limits of quantification of 0.5 ng/mL (E3S), 0.1 ng/mL (PRO) and 2 pg/mL (E1 and E2) were achieved. Most of the comparison
between immunoassays and LC-MS showed poor correlation and proportional differences.
Our LC-MS method is able to simultaneously quantify several steroid hormones with high specificity, accuracy
and sensitivity in serum of two different mammal species. Our method constitutes a useful and performant tool
for veterinary clinicians and LC-MS should thus be used to update and refine the current knowledge about the
endocrinology of pregnancy in mammals
Severe Compromise of Preosteoblasts in a Surgical Mouse Model of Bisphosphonate-Associated Osteonecrosis of the Jaw.
Objectives: The effect of amino-bisphosphonates on osteoblastic lineage and its potential
contribution to the pathogenesis of bisphosphonate-associated osteonecrosis of the jaw
(BONJ) remain controversial. We assessed the effects of zoledronic acid (ZOL) on bone and
vascular cells of the alveolar socket using a mouse model of BONJ.
Material and Methods: Thirty-two mice were treated twice a week with either 100 μg/kg of
ZOL or saline for 12 weeks. The first left maxillary molar was extracted at the third week.
Alveolar sockets were assessed at both 3 weeks (intermediate) and 9 weeks (long-term) after
molar extraction by semi-quantitative histomorphometry for empty lacunae, preosteoblasts
(Osterix), osteoclasts (TRAP), and pericyte-like cells (CD146). Also, the bone
microarchitecture was assessed by micro-CT.
Results: Osteonecrotic-like lesions were observed in 21% of mice. Moreover, a decreased
number of preosteoblasts contrasted with the increased number of osteoclasts at both time
points. In addition, osteoclasts display multinucleation and detachment from the endosteal
surface. Furthermore, the number of pericyte-like cells increased at the intermediate time
point. The alveolar bone mass increased exclusively with long-term ZOL treatment.
Conclusion: The severe imbalance between bone-forming cells and bone-resorbing cells
showed in this study could contribute to the pathogenesis of BONJ
Effects of Hormone Agonists on Sf9 Cells, Proliferation and Cell Cycle Arrest
Methoxyfenozide and methoprene are two insecticides that mimic the action of the main hormones involved in the control of insect growth and development, 20-hydroxyecdysone and juvenile hormone. We investigated their effect on the Spodoptera frugiperda Sf9 cell line. Methoxyfenozide was more toxic than methoprene in cell viability tests and more potent in the inhibition of cellular proliferation. Cell growth arrest occurred in the G2/M phase after a methoprene treatment and more modestly in G1 after methoxyfenozide treatment. Microarray experiments and real-time quantitative PCR to follow the expression of nuclear receptors ultraspiracle and ecdysone receptor were performed to understand the molecular action of these hormone agonists. Twenty-six genes were differentially expressed after methoxyfenozide treatment and 55 genes after methoprene treatment with no gene in common between the two treatments. Our results suggest two different signalling pathways in Sf9 cells
Enseignants et enseignements au cœur de la transmission des savoirs
Ce recueil est consacré à la question de la transmission des savoirs abordée non pas comme un transfert individuel, de personne à personne, dans le cadre de la famille ou de l’atelier, mais comme un système formel combinant de façon plus structurée un ou des enseignements. Cette problématique a fait l’objet de très nombreuses conférences, d’une extrême diversité, présentées lors du 143e Congrès national des sociétés historiques et scientifiques tenu à Paris, en 2018. Leur point commun est principalement de s’interroger sur la transmission des savoirs par l’enseignement, son éventuelle formalisation, ses acteurs, ses méthodes et ses outils, voire ses enjeux. Le Congrès national des sociétés historiques et scientifiques rassemble chaque année universitaires, membres de sociétés savantes et jeunes chercheurs. Ce recueil est issu de travaux présentés lors du 143e Congrès sur le thème « La transmission des savoirs »
Diversité et déterminants virologiques de dissémination des infections à adénovirus chez les greffés pédiatriques de cellules souches hématopoïétiques
CHATENAY M.-PARIS 11-BU Pharma. (920192101) / SudocSudocFranceF
Interactions entre le VIH-1 et l' herpes simplex de type 2 dans le microenvironnement cellulaire et génital
PARIS7-Bibliothèque centrale (751132105) / SudocSudocFranceF
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