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791.
A feeding trial was conducted to estimate the minimal dietary biotin requirement for juvenile grass shrimp, Penaeus monodon. Purified diets with eight levels (0, 0.2, 0.5, 1.0, 3.0, 6.0, 10.0 and 20.0 mg/kg) of supplemental biotin were fed to P. monodon (mean weight 0. 26 +/- 0.01 g) for 8 wk. Each diet was fed to three replicate groups of shrimp. Shrimp fed diets supplemented with biotin (0.2-20.0 mg/kg) had significantly (P < 0.05) higher weight gain, feed efficiency and protein efficiency ratio than those fed the unsupplemented control diet. Weight gain was high in shrimp fed 3. 0-10.0 mg biotin/kg diet and lowest in shrimp fed =1.0 mg/kg diet. Hepatopancreatic biotin concentration in shrimp generally increased as dietary biotin supplementation increased. Highest hepatopancreatic pyruvate carboxylase and acetyl CoA carboxylase activity were in shrimp fed diets with 10 and 20 mg biotin/kg and 3. 0 mg biotin/kg, respectively. Weight gain percentage and protein efficiency ratio of the shrimp analyzed by broken-line regression indicated that the minimal dietary biotin concentration in growing P. monodon is 2.0-2.4 mg/kg. 相似文献
792.
T Nakamura RK Lee SY Nam BK Al-Ramadi PA Koni K Bottomly ER Podack RA Flavell 《Canadian Metallurgical Quarterly》1997,158(5):2090-2098
Prior studies have implicated CD30 as a marker for Th2 cells, but the mechanism that underlies this correlation was unknown. We show here that CD30 was expressed on activated CD4+ T cells in the presence of IL-4. In the absence of endogenously produced IL-4, however, even Th2 lineage cells lost CD30 expression. Thus, CD30 is not an intrinsic marker of Th2 cells, but is inducible by IL-4. CD30 was also found to be down-regulated by IFN-gamma. Committed Th1 effector cells do not express CD30, although differentiating Th1 lineage cells temporarily express CD30. The transient expression of CD30 on differentiating Th1 lineage cells was mainly the result of endogenously produced IL-4 induced by IL-12. Culture of IL-12-primed cells under conditions that reverse the phenotype (Ag plus IL-4) resulted in two cell populations based upon their ability to express CD30. One population responded to IL-4 upon restimulation and became a CD30-positive, Th0-like cell population, while the other remained CD30 negative and synthesized only IFN-gamma. Thus, CD30 expressed on CD4+ T cells reflected the ability of CD4+ T cells to respond to IL-4. 相似文献
793.
794.
Julie Boisramé-Helms Xavier Delabranche Andrey Klymchenko Jocelyne Drai Emilie Blond Fatiha Zobairi Yves Mely Michel Hasselmann Florence Toti Ferhat Meziani 《Lipids》2014,49(11):1091-1099
The aim of this study was to assess how lipid emulsions for parenteral nutrition affect lipopolysaccharide (LPS)‐induced acute monocyte inflammation in vitro. An 18 h long LPS induced human monocyte leukemia cell stimulation was performed and the cell‐growth medium was supplemented with three different industrial lipid emulsions: Intralipid®, containing long‐chain triglycerides (LCT—soybean oil); Medialipid®, containing LCT (soybean oil) and medium‐chain triglycerides (MCT—coconut oil); and SMOFlipid®, containing LCT, MCT, omega‐9 and ‐3 (soybean, coconut, olive and fish oils). Cell viability and apoptosis were assessed by Trypan blue exclusion and flow cytometry respectively. Monocyte composition and membrane remodeling were studied using gas chromatography and NR12S staining. Microparticles released in supernatant were measured by prothrombinase assay. After LPS challenge, both cellular necrosis and apoptosis were increased (threefold and twofold respectively) and microparticle release was enhanced (sevenfold) after supplementation with Medialipid® compared to Intralipid®, SMOFlipid® and monocytes in the standard medium. The monocytes differentially incorporated fatty acids after lipid emulsion challenge. Finally, lipid‐treated cells displayed microparticles characterized by disrupted membrane lipid order, reflecting lipid remodeling of the parental cell plasma membrane. Our data suggest that lipid emulsions differentially alter cell viability, monocyte composition and thereby microparticle release. While MCT have deleterious effects, we have shown that parenteral nutrition emulsion containing LCT or LCT and MCT associated to n‐3 and n‐9 fatty acids have no effect on endotoxin‐induced cell death and inflammation. 相似文献
795.
Fibroblast growth factor-1 (FGF-1) is a potent mitogen for mesoderm- and neuroectoderm-derived cell types in vitro. However, a mutant FGF-1 with deletion in its nuclear localization sequence (NLS, residues 21-27) is not mitogenic in vitro. We demonstrated that synthetic peptides containing this NLS were able to stimulate DNA synthesis in a FGF receptor-independent manner after they were delivered into living NIH 3T3 cells by a cell-permeable peptide import technique. The stimulation of maximal DNA synthesis by these peptides required the presence of peptides during the entire G1 phase of the cell cycle. The mitogenic effect was specific for the NLS of FGF-1 because a peptide with double point mutations at lysine residues was inactive in stimulating DNA synthesis. Our results suggest that the NLS plays an important role in the mitogenic pathway initiated by exogenous FGF-1 by its direct involvement in the nuclear transport and signaling of internalized FGF-1. 相似文献
796.
STUDY OBJECTIVE: "Suicide by cop" is a term used by law enforcement officers to describe an incident in which a suicidal individual intentionally engages in life-threatening and criminal behavior with a lethal weapon or what appears to be a lethal weapon toward law enforcement officers or civilians to specifically provoke officers to shoot the suicidal individual in self-defense or to protect civilians. The objective of this study was to investigate the phenomenon that some individuals attempt or commit suicide by intentionally provoking law enforcement officers to shoot them. METHODS: We reviewed all files of officer-involved shootings investigated by the Los Angeles County Sheriff's Department from 1987 to 1997. Cases met the following criteria: (1) evidence of the individual's suicidal intent, (2) evidence they specifically wanted officers to shoot them, (3) evidence they possessed a lethal weapon or what appeared to be a lethal weapon, and (4) evidence they intentionally escalated the encounter and provoked officers to shoot them. RESULTS: Suicide by cop accounted for 11% (n=46) of all officer-involved shootings and 13% of all officer-involved justifiable homicides. Ages of suicidal individuals ranged from 18 to 54 years; 98% were male. Forty-eight percent of weapons possessed by suicidal individuals were firearms, 17% replica firearms. The median time from arrival of officers at the scene to the time of the shooting was 15 minutes with 70% of shootings occurring within 30 minutes of arrival of officers. Thirty-nine percent of cases involved domestic violence. Fifty-four percent of suicidal individuals sustained fatal gunshot wounds. All deaths were classified by the coroner as homicides, as opposed to suicides. CONCLUSION: Suicide by cop is an actual form of suicide. The most appropriate term for this phenomenon is law enforcement-forced-assisted suicide. Law enforcement agencies may be able to develop strategies for early recognition and handling of law enforcement-forced-assisted suicide (suicide by cop). Health care providers involved in the evaluation of potentially suicidal individuals and in the resuscitation of officer-involved shootings should be aware of law enforcement-forced-assisted suicide as a form of suicide. 相似文献
797.
Eric Blond Anh K. Nguyen Emmanuel de Bilbao Thomas Sayet Athanasios Batakis 《International Journal of Applied Ceramic Technology》2020,17(4):1693-1700
The lifespan of refractory results from a complex interaction between chemistry, thermal conditions, and mechanics. The development of numerical models able to predict the results of such complex multi-physics couplings requires an intensive use of the thermodynamics of irreversible processes framework. Today, the main barriers to reach fully predictive simulations are: the access to relevant data at high temperature (chemical kinetics, chemical expansion coefficient, etc), the numerical complexity and the computational time. The theoretical framework is briefly illustrated on refractory lining applications with a focus on the impact of the swelling induced by corrosion. Then, the numerical difficulties to ensure the numerical convergence and the accuracy of the results when solving classical partial differential equations are examined. Finally, a new approach to model the capillary impregnation by slag, based on percolation theory, is proposed. The basics of this method and the first numerical results are presented. 相似文献