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101.
We previously demonstrated increased apolipoprotein B (apoB) mRNA editing, elevated levels of mRNA for the catalytic component of the apoB mRNA editing complex, apobec-1, and increased secretion of the product of the edited mRNA, apoB48, in very low density lipoproteins (VLDL) in primary cultures of Sprague-Dawley rat hepatocytes following insulin treatment. In order to determine the effect of in vivo hyperinsulinemia on these processes, we determined apoB mRNA editing, apobec-1 expression, hepatic expression of mRNA for apoB and other VLDL apoproteins, and the quantity and composition of plasma VLDL in the hyperinsulinemic fatty Zucker rat. Total apoB mRNA content of the livers of the fatty rats and lean littermates did not differ, however, edited apoB message coding for hepatic apo B48, and abundance of mRNA for the catalytic subunit of the apoB mRNA editing complex, apobec-1, was increased by 1.7-and 3.3-fold, respectively, in fatty rats. ApoCIII mRNA abundance was increased in livers of fatty rats as well, but the abundance of hepatic apoE mRNA in the fatty animal was not different from that of the lean rat. Hepatic apoAI mRNA abundance was also increased in the fatty rats. Associated with increased apoB mRNA editing, was the 1.7-fold increase in the fraction of apoB in plasma as apoB48 in fatty rats. VLDL-triglyceride and-apoB in plasma were 15-and 3-fold higher, respectively, in fatty Zucker rats compared to lean littermates, indicating both enrichment of VLDL with triglycerides and increased accumulation of VLDL particles. Increased hepatic expression of mRNA for apoCIII and apoAI was associated with increased content of apoC (and relative depletion of apoE) in VLDL of fatty rats, and plasma apoAI was increased in fatty Zucker rats, primarily in the HDL fraction. The current study provides further evidence that chronic exposure to high levels of insulin influences both the quantity of and lipid/apoprotein composition of VLDL in plasma. The increased apoC and decreased apoE (as well as increased triglyceride) content of VLDL in the fatty Zucker rat observed in the current study may affect VLDL clearance and therefore may be a factor in the observed accumulation of VLDL in the plasma of the fatty hyperinsulinemic Zucker rats.  相似文献   
102.
The public has become increasingly interested in the welfare of food animals, but the food animal industries possess few mechanisms for public engagement. Here we present results from a web-based forum designed to allow stakeholders to share views on controversial issues in dairying. In response to the question “Should dairy calves be separated from the cow within the first few hours after birth?” participants were able to indicate “yes,” “no,” or “neutral” and either write a reason in support of their view or select reasons provided by other participants. Four independent groups of participants were recruited (a total of 163 people); 31% said they had no involvement in the dairy industry; the remaining 69% (with some involvement in the industry) were students or teachers (33%), animal advocates (13%), producers (11%), veterinarians (9%) and other dairy industry professionals (3%). Overall, little consensus existed among participants across groups; 44% chose “yes,” 48% “no,” and 9% “neutral.” Responses varied with demographics, with opposition to early separation higher among females, animal advocates, and those with no involvement with the dairy industry. A fifth group was recruited at a dairy industry conference (an additional 28 participants); 46% chose “yes,” 32% “no,” and 21% “neutral.” Across all 5 groups, opponents and supporters often referenced similar issues in the reasons they provided. Opponents of early separation contended that it is emotionally stressful for the calf and cow, it compromises calf and cow health, it is unnatural, and the industry can and should accommodate cow-calf pairs. In contrast, supporters of early separation reasoned that emotional distress is minimized by separating before bonds develop, that it promotes calf and cow health, and that the industry is limited in its ability to accommodate cow-calf pairs. These results illustrate the potential of web-based forums to identify areas of agreement and conflict among stakeholders, providing a basis for the development of practices that address shared concerns.  相似文献   
103.
Single molecule (SM) methods are able to resolve structure related dynamics of guest molecules in liquid crystals (LC). Highly diluted small dye molecules on the one hand explore structure formation and LC dynamics, on the other hand they report about a distortion caused by the guest molecules. The anisotropic structure of LC materials is used to retrieve specific conformation related properties of larger guest molecules like conjugated polymers. This in particular sheds light on organization mechanisms within biological cells, where large molecules are found in nematic LC surroundings. This review gives a short overview related to the application of highly sensitive SM detection schemes in LC.  相似文献   
104.
Based on previous findings (Jans, U., Hoigné, J., 1998. Ozone Sci. Eng. 20, 67-87), the activity of activated carbon for the transformation of ozone into *OH radicals including the influence of operational parameters (carbon dose, ozone dose, carbon-type and carbon treatment time) was quantified. The ozone decomposition constant (k(D)) was increased by the presence of activated carbon in the system and depending on the type of activated carbon added, the ratio of the concentrations of *OH radicals and ozone, the R(ct) value ([*OH]/[O3]), was increased by a factor 3-5. The results obtained show that the surface chemical and textural characteristics of the activated carbon determines its activity for the transformation of ozone into *OH radicals. The most efficient carbons in this process are those with high basicity and large surface area. The obtained results show that the interaction between ozone and pyrrol groups present on the surface of activated carbon increase the concentration of O2*- radicals in the system, enhancing ozone transformation into *OH radicals. The activity of activated carbon decreases for extended ozone exposures. This may indicate that activated carbon does not really act as a catalyst but rather as a conventional initiator or promoter for the ozone transformation into *OH radicals. Ozonation of Lake Zurich water ([O3] = 1 mg/L) in presence of activated carbon (0.5 g/L) lead to an increase in the k(D) and R(ct) value by a factor of 10 and 39, respectively, thereby favouring the removal of ozone-resistant contaminants. Moreover, the presence of activated carbon during ozonation of Lake Zurich water led to a 40% reduction in the content of dissolved organic carbon during the first 60 min of treatment. The adsorption of low concentrations of dissolved organic matter (DOM) on activated carbon surfaces did not modify its capacity to initiate/promote ozone transformation into *OH radicals.  相似文献   
105.
In drinking water treatment, the inactivation of microorganisms increases with increasing disinfectant exposure (product of concentration and contact time, CT). Also, the formation of undesired (toxic) disinfection by-products increases with CT. The present study proposes a new concept that uses this undesired side effect of chemical water disinfection for a fast and reliable test of treatment efficiency. In laboratory systems, bromate formation during ozonation and the formation of trihalomethanes during chlorination were used to calculate the disinfectant exposure, which is a measure for the achieved degree of disinfection.  相似文献   
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Forschung im Ingenieurwesen - Nach einer kurzen Übersicht über die bestehenden Toleranzdefinitionen und Meßmethoden von Geradheitsführungen werden zwei neue Methoden...  相似文献   
109.
Cell communication via exosomes is capable of influencing cell fate in stress situations such as exposure to ionizing radiation. In vitro and in vivo studies have shown that exosomes might play a role in out-of-target radiation effects by carrying molecular signaling mediators of radiation damage, as well as opposite protective functions resulting in resistance to radiotherapy. However, a global understanding of exosomes and their radiation-induced regulation, especially within the context of an intact mammalian organism, has been lacking. In this in vivo study, we demonstrate that, compared to sham-irradiated (SI) mice, a distinct pattern of proteins and miRNAs is found packaged into circulating plasma exosomes after whole-body and partial-body irradiation (WBI and PBI) with 2 Gy X-rays. A high number of deregulated proteins (59% of WBI and 67% of PBI) was found in the exosomes of irradiated mice. In total, 57 and 13 miRNAs were deregulated in WBI and PBI groups, respectively, suggesting that the miRNA cargo is influenced by the tissue volume exposed to radiation. In addition, five miRNAs (miR-99b-3p, miR-200a-3p, miR-200a, miR-182-5p, miR-182) were commonly overexpressed in the exosomes from the WBI and PBI groups. In this study, particular emphasis was also given to the determination of the in vivo effect of exosome transfer by intracranial injection in the highly radiosensitive neonatal cerebellum at postnatal day 3. In accordance with a major overall anti-apoptotic function of the commonly deregulated miRNAs, here, we report that exosomes from the plasma of irradiated mice, especially in the case of WBI, prevent radiation-induced apoptosis, thus holding promise for exosome-based future therapeutic applications against radiation injury.  相似文献   
110.
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