Production d'IgG sialylées en CHO et impact sur leurs fonctions effectrices

La sialylation des N-glycanes du fragment Fc des immunogobulines G (IgG) est une modification peu fréquente des IgG humaines. Pourtant, elle est l’objet de beaucoup d’attention depuis que deux articles fondateurs ont été publiés, qui montrent l’un que la sialylation des IgG diminue leur capacité à déclencher la cytotoxicité cellulaire dépendant de l’anticorps (ADCC), et l’autre que les IgG sialylées en α2,6 seraient la fraction efficace des IgG intraveineuses (IgIV) anti-inflammatoires. Les anticorps monoclonaux thérapeutiques, qui sont le plus souvent des IgG recombinantes produites en culture de cellules de mammifère, connaissent depuis la fin des années 90 un succès et une croissance phénoménaux sur le marché pharmaceutique. La maîtrise de la N-glycosylation du Fc des IgG est une clé de l’efficacité des anticorps monoclonaux. Si les IgG sialylées sont des molécules peu fréquentes in vivo, elles sont très rares en culture cellulaire. Dans cette étude, nous avons développé une méthode de production d’IgG avec une sialylation de type humain en cellules CHO. Nous avons travaillé principalement sur la mise au point d’une stratégie de production d’IgG sialylées par co-expression transitoire d’une IgG1 avec la β1,4-galactosyltransférase I (β4GTI) et la β-galactoside-α2,6-sialyltransférase I (ST6GalI). Nous avons montré que cette méthode permettait d’enrichir l’IgG1 en glycane fucosylé di-galactosylé mono-α2,6-sialylé G2FS(6)1, qui est le glycane sialylé présent sur les IgG humaines. Nous avons ensuite adapté cette méthode à la production d’IgG présentant des profils de glycosylation riches en acides sialiques, riches en galactose terminal, et/ou appauvris en fucosylation. L’analyse des profils de glycosylation obtenus par la co-expression de diverses combinaisons enzymatiques avec l’IgG1 native ou une version mutante de l’IgG1 (F243A), a permis de discuter des influences respectives de la sous-galactosylation des IgG1 en CHO et des contraintes structurales du Fc dans la limitation de la sialylation des IgG en CHO. Nous avons ensuite utilisé les IgG1 produites avec différents profils de glycosylation afin d’évaluer l’impact de la sialylation α2,6 sur l’interaction de l’IgG avec le récepteur FcγRIIIa, principal récepteur impliqué dans la réponse ADCC. Nous avons montré que la sialylation α2,6 augmentait la stabilité du complexe formé par l’IgG avec le FcγRIIIa, mais que ce bénéfice n’était pas directement traduit par une augmentation de l’efficacité ADCC de l’anticorps. Enfin, nous avons débuté le développement d’une plateforme d’expression stable d’IgG sialylées compatible avec une production à l’échelle industrielle. Nous avons obtenu une lignée capable de produire des IgG enrichies en G2FS(6)1 à hauteur de 400 mg/L. Cette étude a contribué à une meilleure compréhension de l’impact de la sialylation sur les fonctions effectrices des IgG, et a permis d’augmenter la maîtrise des techniques de modulation du profil de glycosylation des IgG en culture cellulaire.

High-stakes testing and Educational Governance – insights and innovations in European school systems. Special Issue Editorial

International research with regard to the intended as well as to the unintended outcomes and effects of high-stakes testing shows that the impact of high-stakes tests has important consequences for the participants involved in the respective educational systems. The purpose of this special issue is to examine the implementation of high-stakes testing in different national school systems and to refer to the effects in view of the concept of Educational Governance. (DIPF/Orig.)

Impact of genetic polymorphisms determining leukocyte/neutrophil count on chemotherapy toxicity

Nous avons investigué la relation entre les polymorphismes de nucléotides simples (SNPs) chez trois gènes/loci candidats : DARC, CXCL2 et le loci ORMDL3-GSDMA-CSF3 situés sur le chromosome 17q21 et les complications neutropéniques et infectieuses qui en résultent durant la chimiothérapie chez les patients atteints de la leucémie lymphoblastique aigue. Ces loci codent pour certaines composantes du système immunitaire altérant la concentration de chémokines et leur distribution (DARC), stimulant le relâchement et la migration des neutophiles de la moelle épinière (CXCL2) et régulant la prolifération et la survie des granulocytes (G-CSF). Il est possible que des polymorphismes dans ces loci lorsqu’associés à de la chimiothérapie puissent mettre des individus suceptibles à un risque plus élevé de complication reliées à la chimiothérapie. Une sélection des marqueurs SNPs dans ces gènes ont été génotypés chez des enfants traités au CHU Ste-Justine pour une ALL entre 1989 et 2005. Après correction pour tests multiples, un polymorphisme DARC rs3027012 situé dans le 5’UTR a été associé à un compte phagocytaire peu élevé (APC<500 et <1000 cellules/µL, p=0.001 and p=0.0005, respectivement) ainsi qu’une hospitalisation due à une neutropénie (p=0.007) ou due à une infection et/ou neutropénie (p=0.007). Un effet protecteur a été identifié pour la mutation non sense Gly42Asp variant rs12075 (p=0.006). Des polymorphismes sur le chromosome 17q2 étaient associés à une hospitalisation due à une infection (rs3859192, p= 0.004) et à une neutropénie (rs17609240, p=0.006) L’infection était aussi modulée par CXCL2 (rs16850408, p=0.008) Cette étude identifie pour la première fois que les loci modulant le décompte des leucocytes et des neutrophiles pourraient jouer un rôle dans de déclenchement de complications dues à la chimiothérapie et pourraient ainsi servir de marqueurs pour un ajustement et un suivi du traitement.

A REPORT ON THE MITEP PROGRAM AND ITS IMPACT ON MY TEACHING

This report has two major objectives. First, the results of an action research project conducted at my high school concerning the use of graphic organizers and their effects on students' written expression abilities. The findings from this action research project indicate that the use of graphic organizers can prove beneficial to students. The second major objective of this report is to provide a reflection and evaluation of my experiences as a participant in the Michigan Teacher Excellence Program (MiTEP). This program provided middle and high school science teachers with an opportunity to develop research based pedagogy techniques and develop the skill necessary to serve as leaders within the public school science community. The action research project described in the first chapter of this report was a collaborative project I participated in during my enrollment in ED 5705 at Michigan Technological University. I worked closely with two other teachers in my building - Brytt Ergang and James Wright. We met several times to develop a research question, and a procedure for testing our question. Each of us investigated how the use of graphic organizers by students in our classroom might impact their performance on writing assessments. We each collected data from several of our classes. In my case I collected data from 2 different classes over 2 different assignments. Our data was collected and the results analyzed separately from classroom to classroom. After the individual classroom data and corresponding analysis was compiled my fellow collaborators and I got together to discuss our findings. We worked together to write a conclusion based on our combined results in all of our classes.

COMPARATIVE ANALYSIS OF EFFICIENCY AND OPERATING CHARACTERISTICS OF AUTOMOTIVE POWERTRAIN ARCHITECTURES THROUGH CHASSIS DYNAMOMETER TESTING

The thesis "COMPARATIVE ANALYSIS OF EFFICIENCY AND OPERATING CHARACTERISTICS OF AUTOMOTIVE POWERTRAIN ARCHITECTURES THROUGH CHASSIS DYNAMOMETER TESTING" was completed through a collaborative partnership between Michigan Technological University and Argonne National Laboratory under a contractual agreement titled "Advanced Vehicle Characterization at Argonne National Laboratory". The goal of this project was to investigate, understand and document the performance and operational strategy of several modern passenger vehicles of various architectures. The vehicles were chosen to represent several popular engine and transmission architectures and were instrumented to allow for data collection to facilitate comparative analysis. In order to ensure repeatability and reliability during testing, each vehicle was tested over a series of identical drive cycles in a controlled environment utilizing a vehicle chassis dynamometer. Where possible, instrumentation was preserved between vehicles to ensure robust data collection. The efficiency and fuel economy performance of the vehicles was studied. In addition, the powertrain utilization strategies, significant energy loss sources, tailpipe emissions, combustion characteristics, and cold start behavior were also explored in detail. It was concluded that each vehicle realizes different strengths and suffers from different limitations in the course of their attempts to maximize efficiency and fuel economy. In addition, it was observed that each vehicle regardless of architecture exhibits significant energy losses and difficulties in cold start operation that can be further improved with advancing technology. It is clear that advanced engine technologies and driveline technologies are complimentary aspects of vehicle design that must be utilized together for best efficiency improvements. Finally, it was concluded that advanced technology vehicles do not come without associated cost; the complexity of the powertrains and lifecycle costs must be considered to understand the full impact of advanced vehicle technology.

Stress-testing centralised model stores

One of the current challenges in model-driven engineering is enabling effective collaborative modelling. Two common approaches are either storing the models in a central repository, or keeping them under a traditional file-based version control system and build a centralized index for model-wide queries. Either way, special attention must be paid to the nature of these repositories and indexes as networked services: they should remain responsive even with an increasing number of concurrent clients. This paper presents an empirical study on the impact of certain key decisions on the scalability of concurrent model queries, using an Eclipse Connected Data Objects model repository and a Hawk model index. The study evaluates the impact of the network protocol, the API design and the internal caching mechanisms and analyzes the reasons for their varying performance.

Impact of genetic polymorphisms determining leukocyte/neutrophil count on chemotherapy toxicity

Nous avons investigué la relation entre les polymorphismes de nucléotides simples (SNPs) chez trois gènes/loci candidats : DARC, CXCL2 et le loci ORMDL3-GSDMA-CSF3 situés sur le chromosome 17q21 et les complications neutropéniques et infectieuses qui en résultent durant la chimiothérapie chez les patients atteints de la leucémie lymphoblastique aigue. Ces loci codent pour certaines composantes du système immunitaire altérant la concentration de chémokines et leur distribution (DARC), stimulant le relâchement et la migration des neutophiles de la moelle épinière (CXCL2) et régulant la prolifération et la survie des granulocytes (G-CSF). Il est possible que des polymorphismes dans ces loci lorsqu’associés à de la chimiothérapie puissent mettre des individus suceptibles à un risque plus élevé de complication reliées à la chimiothérapie. Une sélection des marqueurs SNPs dans ces gènes ont été génotypés chez des enfants traités au CHU Ste-Justine pour une ALL entre 1989 et 2005. Après correction pour tests multiples, un polymorphisme DARC rs3027012 situé dans le 5’UTR a été associé à un compte phagocytaire peu élevé (APC<500 et <1000 cellules/µL, p=0.001 and p=0.0005, respectivement) ainsi qu’une hospitalisation due à une neutropénie (p=0.007) ou due à une infection et/ou neutropénie (p=0.007). Un effet protecteur a été identifié pour la mutation non sense Gly42Asp variant rs12075 (p=0.006). Des polymorphismes sur le chromosome 17q2 étaient associés à une hospitalisation due à une infection (rs3859192, p= 0.004) et à une neutropénie (rs17609240, p=0.006) L’infection était aussi modulée par CXCL2 (rs16850408, p=0.008) Cette étude identifie pour la première fois que les loci modulant le décompte des leucocytes et des neutrophiles pourraient jouer un rôle dans de déclenchement de complications dues à la chimiothérapie et pourraient ainsi servir de marqueurs pour un ajustement et un suivi du traitement.

The Impact of Regulation on a Firm's Incentives to Invest in Emergent Smart Grid Technologies

This paper analyzes the implementation of new technologies in network industries through the development of a suitable regulatory scheme. The analysis focuses on Smart Grid (SG) technologies which, among others benefits, could save operational costs and reduce the need for further conventional investments in the grid. In spite of the benefits that may result from their implementation, the adoption of SGs by network operators can be hampered by the uncertainties surrounding actual performances. A decision model has been developed to assess the firms' incentives to invest in "smart" technologies under different regulatory schemes. The model also enables testing the impact of uncertainties on the reduction of operational costs, and of conventional investments. Under certain circumstances, it may be justified to support the development and early deployment of emerging innovations that have a high potential to ameliorate the efficiency of the electricity system, but whose adoption faces many uncertainties.

The impact of storage conditions upon gentamicin coated antimicrobial implants

A systematic approach was developed to investigate the stability of gentamicin sulfate (GS) and GS/poly (lactic-co-glycolic acid) (PLGA) coatings on hydroxyapatite surfaces. The influence of environmental factors (light, humidity, oxidation and heat) upon degradation of the drug in the coatings was investigated using liquid chromatography with evaporative light scattering detection and mass spectrometry. GS coated rods were found to be stable across the range of environments assessed, with only an oxidizing atmosphere resulting in significant changes to the gentamicin composition. In contrast, rods coated with GS/PLGA were more sensitive to storage conditions with compositional changes being detected after storage at 60 °C, 75% relative humidity or exposure to light. The effect of γ-irradiation on the coated rods was also investigated and found to have no significant effect. Finally, liquid chromatography–mass spectrometry analysis revealed that known gentamines C1, C1a and C2 were the major degradants formed. Forced degradation of gentamicin coatings did not produce any unexpected degradants or impurities.

An empirical investigation of the impact of global energy transition on Nigerian oil and gas exports

18 months embargo on the thesis and check appendix for copy right materials

The impact of recent educational reforms on minority and low achieving students and on minority and all high achieving students

One of the criticisms of the recent educational reforms sweeping the nation is that low achieving and minority students will not be helped by the reforms. The reforms, some contend, will be harmful to low achieving and minority students because the higher standards and testing programs, which are typically included in the reforms, may actually create new barriers blocking at-risk student progress. This investigation studied this contention in South Carolina, which has been rich in educational reforms. Early evidence from this state indicates that the achievement of Black students and low achieving students of all races was not blocked by the reforms in South Carolina. In fact, low achieving students, Black and all students, made substantial progress in South Carolina since a combination of educational reforms have been in process.

Computer and laboratory simulation in the teaching of neonatal nursing: innovation and impact on learning

Objectives: to evaluate the cognitive learning of nursing students in neonatal clinical evaluation from a blended course with the use of computer and laboratory simulation; to compare the cognitive learning of students in a control and experimental group testing the laboratory simulation; and to assess the extracurricular blended course offered on the clinical assessment of preterm infants, according to the students. Method: a quasi-experimental study with 14 Portuguese students, containing pretest, midterm test and post-test. The technologies offered in the course were serious game e-Baby, instructional software of semiology and semiotechnique, and laboratory simulation. Data collection tools developed for this study were used for the course evaluation and characterization of the students. Nonparametric statistics were used: Mann-Whitney and Wilcoxon. Results: the use of validated digital technologies and laboratory simulation demonstrated a statistically significant difference (p = 0.001) in the learning of the participants. The course was evaluated as very satisfactory for them. The laboratory simulation alone did not represent a significant difference in the learning. Conclusions: the cognitive learning of participants increased significantly. The use of technology can be partly responsible for the course success, showing it to be an important teaching tool for innovation and motivation of learning in healthcare.

Design and specification of a modular automatic testing solution

Electric vehicles and electronic components inside the vehicle are becoming increasingly important. The software as well starts to have a significant impact on modern high-end cars therefore a careful validation process needs to be implemented with the aim of having a bug free product when it is released. The software complexity increases and thus also the testing phases is more demanding. Test can be troublesome and, in some cases, boring and easy. The intelligence can be moved in test definition and writing rather than on test execution. The aim of this document is to start the definition of an automatic modular testing system capable to execute test cycles on systems that interacts with the CAN networks and with DUT that can be touched with a robotic arm. The document defines a first version of the system, in particular the hardware interface part with the aim of taking logs and execute test in an automated fashion with the test engineer can have a higher focus on the test definition and analysis rather than execution.

The Clinical Impact Of Cerebellar Grey Matter Pathology In Multiple Sclerosis.

The cerebellum is an important site for cortical demyelination in multiple sclerosis, but the functional significance of this finding is not fully understood. To evaluate the clinical and cognitive impact of cerebellar grey-matter pathology in multiple sclerosis patients. Forty-two relapsing-remitting multiple sclerosis patients and 30 controls underwent clinical assessment including the Multiple Sclerosis Functional Composite, Expanded Disability Status Scale (EDSS) and cerebellar functional system (FS) score, and cognitive evaluation, including the Paced Auditory Serial Addition Test (PASAT) and the Symbol-Digit Modalities Test (SDMT). Magnetic resonance imaging was performed with a 3T scanner and variables of interest were: brain white-matter and cortical lesion load, cerebellar intracortical and leukocortical lesion volumes, and brain cortical and cerebellar white-matter and grey-matter volumes. After multivariate analysis high burden of cerebellar intracortical lesions was the only predictor for the EDSS (p<0.001), cerebellar FS (p = 0.002), arm function (p = 0.049), and for leg function (p<0.001). Patients with high burden of cerebellar leukocortical lesions had lower PASAT scores (p = 0.013), while patients with greater volumes of cerebellar intracortical lesions had worse SDMT scores (p = 0.015). Cerebellar grey-matter pathology is widely present and contributes to clinical dysfunction in relapsing-remitting multiple sclerosis patients, independently of brain grey-matter damage.

Impact Of Benign Prostatic Hyperplasia Pharmacological Treatment On Transrectal Prostate Biopsy Adverse Effects.

Background. Benign prostatic hyperplasia (BPH) pharmacological treatment may promote a decrease in prostate vascularization and bladder neck relaxation with theoretical improvement in prostate biopsy morbidity, though never explored in the literature. Methods. Among 242 consecutive unselected patients who underwent prostate biopsy, after excluding those with history of prostate biopsy/surgery or using medications not for BPH, we studied 190 patients. On the 15th day after procedure patients were questioned about symptoms lasting over a week and classified according to pharmacological BPH treatment. Results. Thirty-three patients (17%) were using alpha-blocker exclusively, five (3%) 5-alpha-reductase inhibitor exclusively, twelve (6%) patients used both medications, and 140 (74%) patients used none. There was no difference in regard to age among groups (P = 0.5). Postbiopsy adverse effects occurred as follows: hematuria 96 (50%), hematospermia 53 (28%), hematochezia 22 (12%), urethrorrhagia 19 (10%), fever 5 (3%), and pain 20 (10%). There was a significant negative correlation between postbiopsy hematuria and BPH pharmacological treatment with stronger correlation for combined use of 5-alpha-reductase inhibitor and alpha-blocker over 6 months (P = 0.0027). Conclusion. BPH pharmacological treatment, mainly combined for at least 6 months seems to protect against prostate biopsy adverse effects. Future studies are necessary to confirm our novel results.