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51.
Proliferative effects of synthetic peptides from β-lactoglobulin and α-lactalbumin on murine splenocytes 总被引:1,自引:0,他引:1
Arnaud Jacquot Sylvie F. Gauthier Rejean Drouin Yvan Boutin 《International Dairy Journal》2010,20(8):514-521
Eleven peptides, selected on the basis of physicochemical characteristics and their theoretical release from β-lactoglobulin (β-Lg) and α-lactalbumin (α-La) by trypsin or chymotrypsin, were chemically synthesised to evaluate their immunomodulating properties. Murine splenocyte proliferation in the absence and presence of mitogen and different peptide concentrations were measured after 72–96 h incubations. β-Lg f78–83 had no effect on proliferation; β-Lg f15–20, f55–60, f84–91, f92–105, f139–148, f142–148 and α-La f10–16 stimulated proliferation to different extents; β-Lg f1–8, f102–105 and α-La f104–108 showed a cytotoxic effect. Regression analysis revealed the relationship of positive charge, hydrophobicity and length to the stimulatory proliferative effect. β-Lg f15–20, f55–60 and f139–148 also induced various inhibiting and/or stimulating effects on cytokine secretion. The results confirm that peptides releasable by digestive enzymes from α-La and β-Lg have the potential to influence the specific immune response through the modulation of splenocyte proliferation and cytokine secretion. 相似文献
52.
Sylvie Trudel Jean-Marc Lavoie Marie-Claude Paré Witold Suryn 《Software Quality Journal》2006,14(1):7-23
Many small software organizations have recognized the need to improve their software product. Evaluating the software product
alone seems insufficient since it is known that its quality is largely dependant on the process that is used to create it.
Thus, small organizations are asking for evaluation of their software processes and products. The ISO/IEC 14598-5 standard
is already used as a methodology basis for evaluating software products. This article explores how it can be combined with
the CMMI to produce a methodology that can be tailored for process evaluation in order to improve their software processes.
SM: CMMI is a service mark of Carnegie-Mellon University.
Sylvie Trudel has over 20 years of experience in software. She worked for more than 10 years in development and implementation of management
information systems and embedded real-time systems. Since 1996, she works as a process improvement specialist, implementing
best practices into organizations processes from CMM and CMMI models. She performed several CMM and CMMI assessments and participated
in many other CMM assessments such as CBA IPI, SCE, and other proprietary methods. She obtained a bachelors degree in computer
science in 1986 from Laval University in Québec City and a Masters degree in Software Engineering at école de Technologie
Supérieure (éTS) in Montréal. Sylvie is currently working as a software engineering advisor at the Centre de Recherche Informatique
de Montréal (CRIM).
Jean-Marc Lavoie has been working in software development for over 10 years. He performed and published a comparative study between the guide
to the SWEBOK and the CMMI in 2003. Jean-Marc obtained a bachelor degree in Electrical Engineering. He is pursuing a Masters
degree in Software Engineering at école de Technologie Supérieure (éTS) in Montréal while working as a software architect
at Trisotech.
Marie-Claude Pare has been working in software development for 7 years. Marie-Claude obtained a bachelor degree in Software Engineering from
école Polytechnique in Montréal. She is pursuing a Masters degree in Software Engineering at école de Technologie Supérieure
(éTS) in Montréal while working as a software engineer at Motorola GSG Canada.
Dr Witold Suryn is a Professor at the école de technologie supérieure, Montreal, Canada (engineering school of the Université du Québec network
of institutions) where he teaches graduate and undergraduate software engineering courses and conducts research in the domain
of software quality engineering, software engineering body of knowledge and software engineering fundamental principles. Dr
Suryn is also the principal researcher and the director of GELOG : IQUAL, the Software Quality Engineering Research Group
at école de technologie supérieure. From October 2003 Dr. Suryn holds the position of the International Secretary of ISO/IEC
SC7 – System and Software Engineering. 相似文献
53.
The lateral heterogeneity of lipids in the thylakoid membrane has been questioned for over 20 yrs. It is generally believed
that glycerolipids are asymmetrically distributed within the plane of the membrane. In the present investigation, we isolated
several thylakoid membrane domains by using sonication followed by separation in an aqueous dextran-polyethylene glycol two-phase
system. This technique, which avoids detergent treatments, allowed us to obtain stroma and grana lamellae vesicles as well
as grana central core and grana margin vesicles from thylakoids. The relative distribution of the four lipid classes, i.e.,
monogalactosyldiacylglycerol, digalactosyldiacylglycerol, sulfoquinovosyldiacylglycerol, and phosphatidylglycerol, was found
to be statistically identical in all four thylakoid fractions and in whole thylakoids. Similarly, the relative amount of fatty
acids in each individual lipid and the eight main phosphatidylglycerol molecular species was identical in all thylakoid membrane
fractions tested as well as in the intact thylakoid membrane. Based on presently available procedures for obtaining thylakoid
subfractions that are unable to discriminate microdomains within the membrane, it is concluded that glycerolipids are evenly
distributed within the plane of the thylakoid membrane. These data are discussed in terms of “bulk” and “specific” lipids. 相似文献
54.
The use of zinc-coated steels for automotive, construction, and appliance applications has grown continually during the past
decade. An understanding of the effects of process parameters and substrate characteristics on the coating microstructure
is critical for optimizing the performance of the zinc-based coatings. This paper presents an overview of the application
of advanced electron and focused-ion-beam microscopy techniques to characterize the microstructure of galvanized and galvannealed
coatings. 相似文献
55.
For a company, information and communication system is a product of divergent rationalities which come to clash. Dissimilar logic leads to diverging projects : one focused on information aims to integrate and control its processing and flow rate, the other prefers to look at communication as a vector of working together among peers. However beyond these conflicts appears a factor of coherence and cohesion which ultimately helps the rationalities to join. A management able to combine integration of wage earners by identifying the objectives of the company and individualism (information systems is a vector of such a strategy). The goal is to avoid a major risk in form of mass action. The remaining question turns about the ability for innovation allowed to wage-earners in a company driven by standards and believes, in fact ideology. Sticking to standards, in other words conformity seems to leave out marginal handling and conflicting situation sources of innovative spirit. 相似文献
56.
This study examined whether the socioemotional health of children 9–12 years old is related to the physical quality of their residence and neighborhood. The study included 95 children from households with a wide range of incomes in a medium-sized anglophone and a medium-sized francophone Canadian city. Each childȁ9s socioemotional health was assessed and the quality of each childȁ9s housing was assessed on up to 309 aspects of the residence and immediate neighborhood, based on walk-throughs and interviews with the parents in the residences. The childrenȁ9s socioemotional health, as assessed by their parents, was worse when the physical condition of their residenceȁ9s interior, exterior, and immediate neighborhood was worse. This relation remained significant after controlling for household income, parental education and mental health status, the childȁ9s gender, and time lived in the residence. Furthermore, none of these five factors moderated the relation, evidence for its robustness. 相似文献
57.
RT Matheson DR Miller MJ Lacombe YN Han S Iwanaga H Kato KD wuepper 《Canadian Metallurgical Quarterly》1976,58(6):1395-1406
Flaujeac trait is the functional deficiency of a plasma protein of the intrinsic coagulation, kinin-forming, and plasma fibrinolytic pathways. The Flaujeac factor in man has been isolated and tentatively identified as a kininogen of high molecular weight (HMW). Highly purified bovine HMW-kininogen, but not bovine low molecular weight kininogen, repaired Flaujeac factor deficiency. The two subspecies of this molecule, HMW-kininogen a and HMW-kininogen b, also corrected Flaujeac factor deficiency. When bovine HMW-kininogen was incubated with bovine plasma kallikrein, kinin-free HMW-kininogen, bradykinin, and a glycopeptide fragment (peptide 1-2; 12,584 daltons) were rapidly released. None of these fragmentation products corrected Flaujeac factor deficiency alone or in mixtures. The function of HMW-kininogen appeared to depend upon the structural integrity of the native molecule. When injected in concentrations of 2 pmol-8 nmol/0.1 ml, peptide 1-2 caused increased vascular permeability in rabbits, rats, or guinea pigs. The enhanced permeability was maximal within 1-2 min and terminated in 5-10 min, differing from that of bradykinin or histamine. Injected together in equimolar amounts, peptide 1-2 and bradykinin produced a synergistic permeability response which was immediate in onset as well as prolonged in duration. Peptide 1-2 is a rapidly acting, highly basic glyco-peptide which mediates increased vascular permeability in a complementary and synergistic manner with bradykinin. 相似文献
58.
The substitution of W for Mo in the Fe-16.4 Ni-8.2 Mo alloys produces a dual component alloy: i) lath martensite containing
5 wt pet W and ii) 2 pct intermetallic phase, the composition of which is 33.3 Fe-4.4 Ni-62.3 W. The behavior of the two alloys
Fe-16.4 Ni-8.2X (X)=Mo or W) is compared during heating (between 20 and 950°C) at a rate of 300°C/h. For both alloys, the martensite transforms
into austenite in three successive steps by a predominantly diffusional mechanism. The behavior of the two alloys in similar
during isothermal aging at temperatures less than or equal to 550°C. In fact, the aging process takes place in three successive
stages which are studied using the small-angle X-ray scattering technique and electron microscopy. 相似文献
59.
Mach UR Hackling AE Perachon S Ferry S Wermuth CG Schwartz JC Sokoloff P Stark H 《Chembiochem : a European journal of chemical biology》2004,5(4):508-518
Based on N-alkylated 1,2,3,4-tetrahydroisoquinoline derivatives, which are structurally related to the partial agonist BP 897, a series of novel, selective dopamine D3 receptor antagonists has been synthesised. Derivatisation included changes in the arylamide moiety and the tetrahydroisoquinoline substructure leading to compounds with markedly improved selectivities and affinities in the low nanomolar concentration range. From the 55 structures presented here, (E)-3-(4-iodophenyl)-N-(4-(1,2,3,4-tetrahydroisoquinolin-2-yl)butyl)acrylamide (51) has high affinity (Ki(hD3)=12 nM) and a 123-fold preference for the D3 receptor relative to the D2 receptor subtype. Its pharmacological profile offers the prospect of a novel radioligand as a tool for various dopamine D3-receptor-related in vitro and in vivo investigations. 相似文献
60.
Structural diversity of sphingomyelin microdomains 总被引:2,自引:0,他引:2
In cells plasma membrane, sphingomyelin (SM) plays a key role in the formation of a category of lipid microdomains enriched in cholesterol (Chl) often referred to as rafts. Atomic force microscopy (AFM) was used to analyze the mesoscopic topography of enriched SM microdomains in supported bilayers made of SM/dioleoylphosphatidylcholine (SM/DOPC) and SM/palmitoyl-oleoyl-phosphatidylcholine (SM/POPC) equimolar mixtures, in buffer, at room temperature. Gel–fluid phase separation occurs in both SM/DOPC and SM/POPC bilayers. The gel phase SM-enriched microdomains adopt a variety of size, shape and mesoscopic structure, from homogeneous flat domains of a few hundreds of nanometer in diameter to domains of several micrometers made of closely packed globular structures. Gel–gel phase separation in SM domains is also observed which gives rise to different structures for the diunsaturated and the mixed-saturated PC species. These differences could also extend to the interactions with Chl. This suggests that studies on rafts formation commonly performed using SM/DOPC mixture as a model should also include the physiologically more relevant POPC species. 相似文献