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1.
The identification of neuroprotectin D1 (NPD1), a biosynthetic product of docosahexaenoic acid (DHA), in brain and retina as well as the characterization of its bioactivity, is generating a renewed interest in the functional role and pathophysiological significance of omega-3 fatty acids in the central nervous system. Neurotrophins, particularly pigment epithelium-derived factor (PEDF), induce NPD1 synthesis and its polarized apical secretion, implying paracrine and autocrine bioactivity of this lipid mediator. Also, DHA and PEDF synergistically activate NPD1 synthesis and antiapoptotic protein expression and decreased proapoptotic Bcl-2 protein expression and caspase 3 activation during oxidative stress. In experimental stroke, endogenous NPD1 synthesis was found to be upregulated, and the infusion of the lipid mediator into the brain under these conditions revealed neuroprotective bioactivity of NPD1. The hippocampal CA1 region from Alzheimer's disease (AD) patients (rapidly sampled) shows a major reduction in NPD1. The interplay of DHA-derived neuroprotective signaling aims to counteract proinflammatory, cell-damaging events triggered by multiple, converging cytokine and amyloid peptide factors, as in the case of AD. Generation of NPD1 from DHA thereby appears to redirect cellular fate toward successful preservation of retinal pigment epithelial (RPE)-photoreceptor cell integrity and brain cell aging. The Bcl-2 pro- and antiapoptotic proteins, neurotrophins, and NPD1, lie along a cell fate-regulatory pathway whose component members are highly interactive, and have potential to function cooperatively in cell survival. Agents that stimulate NPD1 biosynthesis, NPD1 analogs, or dietary regimens may be useful as new preventive/therapeutic strategies for neurodegenerative diseases.  相似文献   

2.
Eco-efficiency at the product level is defined as product value per unit of environmental impact. In this paper we present a method for quantifying the eco-efficiency using quality function deployment (QFD) and life-cycle impact assessment (LCIA). These well-known tools are widely used in the manufacturing industry.
QFD, which is one of the methods used in product development based on consumer preferences, is introduced to calculate the product value. An index of the product value is calculated as the weighted average of improvement rates of quality characteristics. The importance of customer requirements, derived from the QFD matrix, is applied.
Environmental impacts throughout a product life cycle are calculated based on an LCIA method widely used in Japan. By applying the LCIA method of endpoint type, the endpoint damage caused by various life-cycle inventories is calculated. Willingness to pay is applied to integrate it into a single index.
Eco-design support tools, namely, the life-cycle planning (LCP) tool and the life-cycle assessment (LCA) tool, have already been developed. Using these tools, data required for calculation of the eco-efficiency of products can be collected. The product value is calculated based on QFD data stored in the LCP tool and the environmental impact is calculated using the LCA tool.
Case studies of eco-efficiency are adopted and the adequacy of this method is clarified. Several advantages of this method are characterized.  相似文献   

3.
Abstract

The effectiveness of the traditional risk analysis approach is enhanced by the integration of the fuzzy logic and Multi-Criteria Decision Making (MCDM) methods. In fact, human decisions are ambiguous and blurred and do not fit to express with absolute numerical values. For this reason, it is more realistic to use verbal variables in modeling human decisions. In this paper, a new fuzzy based hazard evaluation approach is proposed to deal with the risk assessment process. The proposed methodology consists on MCDM with a fuzzy system which includes a hybrid structure consists the Pythagorean Fuzzy Analytic Hierarchy Process (PFAHP) method with cosine similarity, and also Neutrosophic Analytic Hierarchy Process (NFAHP) to support facing of uncertainty in the risk assessment process for asphalt production, laying and coating services which are important and should be examined in terms of occupational health and safety. To the best of our knowledge, this study is the first to propose facing uncertainty in the hazard evaluations and risk assessment for asphalt production, laying, and coating services. As an outcome of the analysis by the proposed method, according to PFAHP and NFAHP methodologies the criterions “manometer size” and “calibration” are found to be most critical factors, respectively.  相似文献   

4.
Acid sphingomyelinase (ASMase)-deficient Niemann-Pick disease (NPD) is caused by mutations in the sphingomyelin phosphodiesterase 1 (SMPD1) gene, resulting in accumulation of sphingomyelin in the lysosomes and secondary changes in cholesterol metabolism. We hypothesized that the oxidation product of cholesterol, 7-ketocholesterol (7-KC), might increase in the plasma of patients with ASMase-deficient NPD. In this study, a rapid and nonderivatized method of measurement of plasma 7-KC by liquid chromatography-tandem mass spectrometry (LC-MS/MS) was developed. Plasma samples from healthy subjects, patients with ASMase-deficient NPD, nonaffected ASMase-deficient NPD heterozygotes, Niemann-Pick type C (NPC) disease, glycogen storage disorder type II (GSDII), Gaucher disease (GD), mucopolysaccharidosis type II (MPSII), Krabbe disease (KD), and metachromatic leukodystrophy (MLD) were tested retrospectively. Markedly elevated 7-KC was found in patients with ASMase-deficient NPD and NPC disease that showed significant differences from ASMase-deficient NPD heterozygotes; patients with GSDII, GD, MPSII, KD, and MLD; and normal controls. The analysis of plasma 7-KC by LC-MS/MS offers the first simple, quantitative, and highly sensitive method for detection of ASMase-deficient NPD and could be useful in the diagnosis of both ASMase-deficient NPD and NPC disease.  相似文献   

5.
To incorporate quality by design concepts into the management of leachables, an emphasis is often put on understanding the extractable profile for the materials of construction for manufacturing disposables, container-closure, or delivery systems. Component manufacturing processes may also impact the extractable profile. An approach was developed to (1) identify critical components that may be sources of leachables, (2) enable an understanding of manufacturing process factors that affect extractable profiles, (3) determine if quantitative models can be developed that predict the effect of those key factors, and (4) evaluate the practical impact of the key factors on the product. A risk evaluation for an inhalation product identified injection molding as a key process. Designed experiments were performed to evaluate the impact of molding process parameters on the extractable profile from an ABS inhaler component. Statistical analysis of the resulting GC chromatographic profiles identified processing factors that were correlated with peak levels in the extractable profiles. The combination of statistically significant molding process parameters was different for different types of extractable compounds. ANOVA models were used to obtain optimal process settings and predict extractable levels for a selected number of compounds. The proposed paradigm may be applied to evaluate the impact of material composition and processing parameters on extractable profiles and utilized to manage product leachables early in the development process and throughout the product lifecycle.KEY WORDS: design of experiments, extractables, injection molding, leachables, process parameters, quality by design  相似文献   

6.
Niemann-Pick type D (NPD) disease is a progressive neurodegenerative disorder characterized by the accumulation of tissue cholesterol and sphingomyelin. This disorder is relatively common in southwestern Nova Scotia, because of a founder effect. Our previous studies, using classic linkage analysis of this large extended kindred, defined the critical gene region to a 13-cM chromosome segment between D18S40 and D18S66. A recently isolated gene from this region, NPC1, is mutated in the majority of patients with Niemann-Pick type C disease. We have identified a point mutation within this gene (G3097-->T; Gly992-->Trp) that shows complete linkage disequilibrium with NPD, confirming that NPD is an allelic variant of NPC1.  相似文献   

7.
Acid sphingomyelinase (ASM; sphingomyelin phosphodiesterase, EC 3.1.4.12) is the lysosomal enzyme that hydrolyzes sphingomyelin (SPM) to phosphorylcholine and ceramide. An inherited deficiency of ASM activity results in Types A and B Niemann-Pick disease (NPD). In this study we report a new assay method to detect ASM activity and diagnose NPD using the fluorescent substrate BODIPY C12-SPM and reverse-phase high-performance liquid chromatography (HPLC). The reaction product, BODIPY C12-ceramide (B12Cer), could be clearly and efficiently separated from the substrate within 4 min using a reverse-phase column (Aquasil C18, Keystone Scientific). Femtomole quantities of B12Cer could be detected in as little as 1.0 micro l of human plasma, providing a sensitive measure of ASM activity. The mean ASM activity in human plasma from NPD patients (36 pmol/ml/h) was only 2.7% of that in normal plasma (1334 pmol/ml/h), confirming the specificity and diagnostic value of this new assay method. Importantly, the mean ASM activity in human plasma from NPD carriers (258.3 pmol/ml/h) also was significantly reduced (19.5% of normal). The ranges of ASM plasma activities in NPD patients (N=19), NPD carriers (N=11), and normal subjects (N=15) were 2.5-97.3, 108-551, and 1030-2124 pmol/ml/h, respectively. Based on these results, we suggest that this fluorescence-based HPLC assay method is a reliable, rapid, and highly sensitive technique to determine ASM activity and that plasma is a very reliable and simple source for the accurate diagnosis of NPD patients and carriers based on ASM activity.  相似文献   

8.
In 13 cystic fibrosis (CF) patients of 5 to 23 years of age with a known mutation spectrum of gene CFTR, sweat chloride values and nasal-potential differences (NPD) were measured and localization characteristics of the protein product of gene CFTR in the cells of nasal epithelium were studied. Sweat Chloride values were normal or boundary (24 to 62 mM/l) in six CF patients. In seven CF patients, these values were significantly above the estimates for the control group. On average, the NPD values were -44.7 +/- 2.2 mV (from -32.5 to -68.9 mV) and -17.2 +/- 1.8 mV (from -6.8 to -30.2 mV) in CF patients and the control group, respectively. Histochemical studies clearly revealed the localization of the CFTR protein on the apical membrane of the nasal epithelium. Depending on the type of mutation, the protein product of gene CFTR was either absent or regularly distributed in the cytoplasm in CF patients; it was not detected in the apical membrane. Thus, NPD measurements and the analysis of the localization of the protein product of gene CFTR in scrapes of nasal epithelium were shown to be additional, highly informative methods of CF diagnostics.  相似文献   

9.
A short survey and critical analysis of previously proposed criteria for growth control of populations of microorganisms in the chemostat are presented. Based on the analysis of a mathematical model of the steady-state of a microbial population in the chemostat, an adequate control criterion is suggested, along with a method to identify the corresponding regulating factors. The new control criterion is expressed as a product of the factor transformation coefficient and the biomass sensitivity coefficient (SC) with respect to the change of the factor at the chemostat inlet (referred to in the sequel as the biomass SC). The control criterion determines the strength of the control exerted by this or that factor. The method of determination of the regulating factors consists in experimental determination of the real SCs for factors and the biomass and in calculating on this basis the corresponding ideal SCs for constant factor transformation coefficients. The ideal SCs are shown to add up to an integer value, a constraint that we call "quantization" relationships. Such relationships are used to test the completeness of the drawn list of control factors. The proposed method was applied to our own and literature data.  相似文献   

10.
In literature, we can find different metrics to evaluate the detected edges in digital images, like Pratt''s figure of merit (FOM), Jaccard’s index (JI) and Dice’s coefficient (DC). These metrics compare two images, the first one is the reference edges image, and the second one is the detected edges image. It is important to mention that all existing metrics must binarize images before their evaluation. Binarization step causes information to be lost because an incomplete image is being evaluated. In this paper, we propose a fuzzy index (FI) for edge evaluation that does not use a binarization step. In order to process all detected edges, images are represented in their fuzzy form and all calculations are made with fuzzy sets operators and fuzzy Euclidean distance between both images. Our proposed index is compared to the most used metrics using synthetic images, with good results.  相似文献   

11.
12.
The integrity of the retinal pigment epithelial (RPE) cell is essential for the survival of rod and cone photoreceptor cells. Several stressors, including reactive oxygen species, trigger apoptotic damage in RPE cells preceded by an anti-inflammatory, pro-survival response, the formation of neuroprotectin D1 (NPD1), an oxygenation product derived from the essential omega-3 fatty acid family member docosahexaenoic acid. To define the ability of NPD1 and other endogenous novel lipid mediators in cell survival, we generated a stable knockdown human RPE (ARPE-19) cell line using short hairpin RNA to target 15-lipoxygenase-1. The 15-lipoxygenase-1-deficient cells exhibited 30% of the protein expression, and 15-lipoxygenase-2 remained unchanged, as compared with an ARPE-19 cell line control established using nonspecific short hairpin RNA transfected cells. NPD1 synthesis was stimulated by tumor necrosis factor α/H2O2-mediated oxidative stress in nonspecific cells (controls), whereas in silenced cells, negligible amounts of NPD1, 12(S)- and 15(S)-hydroxyeicosatetraenoic acid, and lipoxin A4 were found under these conditions. Neither control nor the deficient cells showed an increase in 15-lipoxygenase-1 protein content after 16 h of oxidative stress, suggesting that the increased activity of 15-lipoxygenase-1 is due to activation of pre-existing proteins. 15-Lipoxygenase-silenced cells also displayed an exacerbated sensitivity to oxidative stress-induced apoptosis when compared with the control cells. NPD1 selectively and potently rescued 15-lipoxygenase-silenced cells from oxidative stress-induced apoptosis. These results demonstrate that 15-lipoxygenase-1 is activated by oxidative stress in ARPE-19 cells and that NPD1 is part of an early survival signaling in RPE cells.  相似文献   

13.
The central Iberian Peninsula has one of the highest densities of roe deer populations in Spain. A new motorway is planned to pass through the middle of the distribution of roe deer, thus making it necessary to conduct a connectivity analysis. A map of resistance to roe deer dispersal movements was obtained based on the literature and expert judgment. Three factors were selected: land use (defined by the ability to hide movements, food source, and degree of naturalness), landforms, and influence due to proximity to elements that increase (such as roads and urban areas) or decrease (water resources and proximity to optimal habitat patches) resistance at the local level. Different combinations of factors derived using the analytical hierarchy and fuzzy logic processes were analysed and compared with the real distribution of the species. More realistic resistance (cost) values were obtained for gamma values close to 0.9. This highlights the greater predominance of the fuzzy sum over the fuzzy product in modelling the cost surface. Better results were obtained in scenarios where the predominant factors were either land use and landforms or land use and proximity to human-modified areas. This indicates that roe deer will readily range far from their optimal patches if the land use provides partial cover. These movements appear to be conditioned by steep terrain. Our case study offers a good example of building a cost resistance matrix to help locate areas where the expansion of the species may be curbed or encouraged.  相似文献   

14.
Process analytical technology is gaining interest in the biopharmaceutical industry as a means to enable consistency in processing and thereby in product quality via process control. Protein refolding is known to be significantly impacted by critical process parameters and feed material attributes including composition and pH of the solubilisation and refolding buffers. Hence, to achieve robust process control and product quality, these attributes and parameters need to be monitored. This paper presents an approach towards statistical process control and monitoring of protein refolding, from buffer preparation to refold quenching, during manufacturing of therapeutic proteins from Escherichia coli based systems. The proposed approach utilises measurements of online redox potential, temperature, and pH for development of a statistical model. The model has then been integrated with LabView to permit real-time monitoring of the refolding process. The proposed system has been demonstrated to successfully identify process deviations and thereby enable process control for manufacturing product of consistent quality.  相似文献   

15.
The regulatory approval of a biosimilar product is contingent on the favorable comparability of its safety and efficacy to that of the innovator product. As such, it is important to match the critical quality attributes of the biosimilar product to that of the innovator product. The N-glycosylation profile of a monoclonal antibody (mAb) can influence effector function activities such as antibody-dependent cell-mediated cytotoxicity (ADCC) and complement-dependent cytotoxicity. In this study, we describe efforts to modulate the high-mannose (HM) levels of a biosimilar mAb produced in a Chinese hamster ovary cell fed-batch process. Because the HM level of the mAb was observed to impact ADCC activity, it was desirable to match it to the innovator mAb's levels. Several cell culture process related factors known to modulate the HM content of N-glycosylation were investigated, including osmolality, ammonium chloride (NH4Cl) addition, glutamine concentration, monensin addition, and the addition of alternate sugars and amino sugars to the feed medium. The process conditions evaluated varied in impact on HM levels, process performance and product quality. One condition, the addition of alternate sugars and amino sugars to feed medium, was identified as the preferred method for increasing HM levels with minimal disruptions to process performance or other product quality attributes. Interestingly, a secondary interaction between sugar and amino sugar supplemented feeds and osmolality was observed during process scale-up. These studies demonstrate sugar and amino sugar concentrations and osmolality are critical variables to evaluate to match HM content in biosimilar and their innovator mAbs.  相似文献   

16.
A short survey and a critical analysis of previously proposed criteria for growth control of populations of microorganisms in the chemostat are presented. Based on the analysis of a mathematical model of the steady state of a microbial population in the chemostat, an adequate control criterion is suggested, along with a method to identify the corresponding control factors. The new control criterion is expressed as a product of the factor transformation coefficient and the sensitivity coefficient (SC) of the biomass with respect to the change in the factor at the chemostat inlet (hereinafter, the biomass SC). The control criterion determines the strength of the control exerted by a factor. The method of determining control factors consists in experimental determination of the real SCs for factors and the biomass and calculation on this basis of the corresponding ideal SCs, assuming constant factor transformation coefficients. The ideal SCs are shown to add up to integer values, a constraint that we call quantization relationships. Such relationships are used to test the completeness of the list of control factors. The proposed method was applied to both our own and literature data.Translated from Mikrobiologiya, Vol. 74, No. 1, 2005, pp. 5–16.Original Russian Text Copyright © 2005 by Adamovich, Rogozin, Degermendzhi.  相似文献   

17.
Human and animal studies have revealed a strong association between periconceptional environmental factors, such as poor maternal diet, and an increased propensity for cardiovascular and metabolic disease in adult offspring. Previously, we reported cardiovascular and physiological effects of maternal low protein diet (LPD) fed during discrete periods of periconceptional development on 6-month-old mouse offspring. Here, we extend the analysis in 1 year aging offspring, evaluating mechanisms regulating growth and adiposity. Isocaloric LPD (9% casein) or normal protein diet (18% casein; NPD) was fed to female MF-1 mice either exclusively during oocyte maturation (for 3.5 days prior to mating; Egg-LPD, Egg-NPD, respectively), throughout gestation (LPD, NPD) or exclusively during preimplantation development (for 3.5 days post mating; Emb-LPD). LPD and Emb-LPD female offspring were significantly lighter and heavier than NPD females respectively for up to 52 weeks. Egg-LPD, LPD and Emb-LPD offspring displayed significantly elevated systolic blood pressure at 52 weeks compared to respective controls (Egg-NPD, NPD). LPD females had significantly reduced inguinal and retroperitoneal fat pad: body weight ratios compared to NPD females. Expression of the insulin receptor (Insr) and insulin-like growth factor I receptor (Igf1r) in retroperitoneal fat was significantly elevated in Emb-LPD females (P<0.05), whilst Emb-LPD males displayed significantly decreased expression of the mitochondrial uncoupling protein 1 (Ucp1) gene compared to NPD offspring. LPD females displayed significantly increased expression of Ucp1 in interscapular brown adipose tissue when compared to NPD offspring. Our results demonstrate that aging offspring body weight, cardiovascular and adiposity homeostasis can be programmed by maternal periconceptional nutrition. These adverse outcomes further exemplify the criticality of dietary behaviour around the time of conception on long-term offspring health.  相似文献   

18.
Extended monod kinetics for substrate, product, and cell inhibition   总被引:8,自引:0,他引:8  
A generalized form of Monod kinetics is proposed to account for all kinds of product, cell, and substrate inhibition. This model assumes that there exists a critical inhibitor concentration above which cells cannot grow, and that the constants of the Monod equation are functions of this limiting inhibitor concentration. Methods for evaluating the constants of this rate form are presented. Finally the proposed kinetic form is compared with the available data in the literature, which unfortunately is very sparse. In all cases, this equation form fitted the data very well.  相似文献   

19.
Currently, marketed influenza vaccines are only efficient against homologous viruses, thus requiring a seasonal update based on circulating subtypes. This constant reformulation adds several challenges to manufacturing, particularly in purification due to the variation of the physicochemical properties of the vaccine product. A universal platform approach capable of handling such variation is therefore of utmost importance. In this work, a filtration‐based approach is explored to purify influenza virus‐like particles. Switching from adsorptive separation to size‐based purification allows overcoming the differences in retention observed for different influenza strains. The proposed process employs a cascade of ultrafiltration and diafiltration steps, followed by a sterile filtration step. Different process parameters are assessed in terms of product recovery and impurities’ removal. Membrane chemistry, pore size, operation modes, critical flux, transmembrane pressure, and permeate control strategies are evaluated. After membrane selection and parameter optimization, concentration factors and diafiltration volumes are also defined. By optimizing the filtration mode of operation, it is possible to achieve product recoveries of approximately 80%. Overall, the process time is decreased by 30%, its scalability is improved, and the costs are reduced due to the removal of chromatography and associated buffer consumptions, cleaning, and its validation steps.  相似文献   

20.
Bioprocesses and biosystems have nonlinear and multiple operation patterns depending on the influent loads, temperatures, the activity of microorganisms, and other factors. In this paper, an integrated framework of nonlinear modeling and process monitoring methods is developed for a complex biological process. The proposed method is based on modeling by fuzzy partial least squares (FPLS) and on process monitoring by a statistical decomposition, which is suitable for predicting and supervising a nonlinear biological process. Case studies in the bio-simulated process and industrial biological plant show that the proposed method can give superior prediction and monitoring performance in complex biological plants compared to other linear and nonlinear methods, since it can effectively capture the nonlinear causal relationship within the biosystem. This gives us the integrated framework that is able to both model and monitor the nonlinear bioprocess simultaneously.  相似文献   

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