963 resultados para partition in micellar phase
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Cilengitide, a cyclicized arginine-glycine-aspartic acid-containing pentapeptide, potently blocks ανβ3 and ανβ5 integrin activation. Integrins are upregulated in many malignancies and mediate a wide variety of tumor-stroma interactions. Cilengitide and other integrin-targeting therapeutics have preclinical activity against many cancer subtypes including glioblastoma (GBM), the most common and deadliest CNS tumor. Cilengitide is active against orthotopic GBM xenografts and can augment radiotherapy and chemotherapy in these models. In Phase I and II GBM trials, cilengitide and the combination of cilengitide with standard temozolomide and radiation demonstrate consistent antitumor activity and a favorable safety profile. Cilengitide is currently under evaluation in a pivotal, randomized Phase III study (Cilengitide in Combination With Temozolomide and Radiotherapy in Newly Diagnosed Glioblastoma Phase III Randomized Clinical Trial [CENTRIC]) for newly diagnosed GBM. In addition, randomized controlled Phase II studies with cilengitide are ongoing for non-small-cell lung cancer and squamous cell carcinoma of the head and neck. Cilengitide is the first integrin inhibitor in clinical Phase III development for oncology.
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The main goal of the research described in this report was to evaluate countermeasures that agencies can use to reduce speeds as drivers enter rural communities located on high-speed roadways. The objectives of this study were as follows: * Identify and summarize countermeasures used to manage speeds in transition zones * Demonstrate the effectiveness of countermeasures that are practical for high- to low-speed transition zones * Acquire additional information about countermeasures that may show promise but lack sufficient evidence of effectiveness * Develop an application toolbox to assist small communities in selecting appropriate transition zones and effective countermeasures for entrances to small rural communities The team solicited small communities that were interested in participating in the Phase II study and several communities were also recommended. The treatments evaluated were selected by carefully considering traffic-calming treatments that have been used effectively in other countries for small rural communities, as well as the information gained from the first phase of the project. The treatments evaluated are as follows: * Transverse speed bars * Colored entrance treatment * Temporary island * Radar-activated speed limit sign * Speed feedback sign The toolbox publication and four focused tech briefs also cover the results of this work.
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Plasmodium vivax circumsporozoite (CS) protein is a leading malaria vaccine candidate. We describe the characterization of specific immune responses induced in 21 malaria-naive volunteers vaccinated with long synthetic peptides derived from the CS protein formulated in Montanide ISA 720. Both antibody- and cell-mediated immune responses were analyzed. Antibodies were predominantly of IgG1 and IgG3 isotypes, recognized parasite proteins on the immunofluorescent antibody test, and partially blocked sporozoite invasion of hepatoma cell lines in vitro. Peripheral blood mononuclear cells from most volunteers (94%) showed IFN-γ production in vitro upon stimulation with both long signal peptide and short peptides containing CD8+ T-cell epitopes. The relatively limited sample size did not allow conclusions about HLA associations with the immune responses observed. In summary, the inherent safety and tolerability together with strong antibody responses, invasion blocking activity, and the IFN-γ production induced by these vaccine candidates warrants further testing in a phase II clinical trial.
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BACKGROUND: Thymostimulin is a thymic peptide fraction with immune-mediated cytotoxicity against hepatocellular carcinoma (HCC) in vitro and palliative efficacy in advanced HCC in two independent phase II trials. The aim of this study was to assess the efficacy of thymostimulin in a phase III trial. METHODS: The study was designed as a prospective randomised, placebo-controlled, double-blind, multicenter clinical phase III trial. Between 10/2002 and 03/2005, 135 patients with locally advanced or metastasised HCC (Karnofsky >or=60%/Child-Pugh <or= 12) were randomised to receive thymostimulin 75 mg s.c. 5x/week or placebo stratified according to liver function. Primary endpoint was twelve-month survival, secondary endpoints overall survival (OS), time to progression (TTP), tumor response, safety and quality of life. A subgroup analysis according to liver function, KPS and tumor stage (Okuda, CLIP and BCLC) formed part of the protocol. RESULTS: Twelve-month survival was 28% [95%CI 17-41; treatment] and 32% [95%CI 19-44; control] with no significant differences in median OS (5.0 [95% CI 3.7-6.3] vs. 5.2 [95% CI 3.5-6.9] months; p = 0.87, HR = 1.04 [95% CI 0.7-1.6]) or TTP (5.3 [95%CI 2.0-8.6] vs. 2.9 [95%CI 2.6-3.1] months; p = 0.60, HR = 1.13 [95% CI 0.7-1.8]). Adjustment for liver function, Karnofsky status or tumor stage did not affect results. While quality of life was similar in both groups, fewer patients on thymostimulin suffered from accumulating ascites and renal failure. CONCLUSIONS: In our phase III trial, we found no evidence of any benefit to thymostimulin in the treatment of advanced HCC and there is therefore no justification for its use as single-agent treatment. The effect of thymostimulin on hepato-renal function requires further confirmation. TRIAL REGISTRATION: Current Controlled Trials ISRCTN64487365.
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The main goal of the research described in this report was to evaluate countermeasures that agencies can use to reduce speeds as drivers enter rural communities located on high-speed roadways. The objectives of this study were as follows: * Identify and summarize countermeasures used to manage speeds in transition zones * Demonstrate the effectiveness of countermeasures that are practical for high- to low-speed transition zones * Acquire additional information about countermeasures that may show promise but lack sufficient evidence of effectiveness * Develop an application toolbox to assist small communities in selecting appropriate transition zones and effective countermeasures for entrances to small rural communities The team solicited small communities that were interested in participating in the Phase II study and several communities were also recommended. The treatments evaluated were selected by carefully considering traffic-calming treatments that have been used effectively in other countries for small rural communities, as well as the information gained from the first phase of the project. The treatments evaluated are as follows: * Transverse speed bars * Colored entrance treatment * Temporary island * Radar-activated speed limit sign * Speed feedback sign The toolbox publication and four focused tech briefs also cover the results of this work.
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Culverts are common means to convey flow through the roadway system for small streams. In general, larger flows and road embankment heights entail the use of multibarrel culverts (a.k.a. multi-box) culverts. Box culverts are generally designed to handle events with a 50-year return period, and therefore convey considerably lower flows much of the time. While there are no issues with conveying high flows, many multi-box culverts in Iowa pose a significant problem related to sedimentation. The highly erosive Iowa soils can easily lead to the situation that some of the barrels can silt-in early after their construction, becoming partially filled with sediment in few years. Silting can reduce considerably the capacity of the culvert to handle larger flow events. Phase I of this Iowa Highway Research Board project (TR-545) led to an innovative solution for preventing sedimentation. The solution was comprehensively investigated through laboratory experiments and numerical modeling aimed at screening design alternatives and testing their hydraulic and sediment conveyance performance. Following this study phase, the Technical Advisory Committee suggested to implement the recommended sediment mitigation design to a field site. The site selected for implementation was a 3-box culvert crossing Willow Creek on IA Hwy 1W in Iowa City. The culvert was constructed in 1981 and the first cleanup was needed in 2000. Phase II of the TR 545 entailed the monitoring of the site with and without the selfcleaning sedimentation structure in place (similarly with the study conducted in laboratory). The first monitoring stage (Sept 2010 to December 2012) was aimed at providing a baseline for the operation of the as-designed culvert. In order to support Phase II research, a cleanup of the IA Hwy 1W culvert was conducted in September 2011. Subsequently, a monitoring program was initiated to document the sedimentation produced by individual and multiple storms propagating through the culvert. The first two years of monitoring showed inception of the sedimentation in the first spring following the cleanup. Sedimentation continued to increase throughout the monitoring program following the depositional patterns observed in the laboratory tests and those documented in the pre-cleaning surveys. The second part of Phase II of the study was aimed at monitoring the constructed self-cleaning structure. Since its construction in December 2012, the culvert site was continuously monitored through systematic observations. The evidence garnered in this phase of the study demonstrates the good performance of the self-cleaning structure in mitigating the sediment deposition at culverts. Besides their beneficial role in sediment mitigation, the designed self-cleaning structures maintain a clean and clear area upstream the culvert, keep a healthy flow through the central barrel offering hydraulic and aquatic habitat similar with that in the undisturbed stream reaches upstream and downstream the culvert. It can be concluded that the proposed self-cleaning structural solution “streamlines” the area upstream the culvert in a way that secures the safety of the culvert structure at high flows while producing much less disturbance in the stream behavior compared with the current constructive approaches.
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PURPOSE: In the setting of a prospective clinical trial, we determined the predictive value of the methylation status of the O-6-methylguanine-DNA methyltransferase (MGMT) promoter for outcome in glioblastoma patients treated with the alkylating agent temozolomide. Expression of this excision repair enzyme has been associated with resistance to alkylating chemotherapy. EXPERIMENTAL DESIGN: The methylation status of MGMT in the tumor biopsies was evaluated in 38 patients undergoing resection for newly diagnosed glioblastoma and enrolled in a Phase II trial testing concomitant and adjuvant temozolomide and radiation. The epigenetic silencing of the MGMT gene was determined using methylation-specific PCR. RESULTS: Inactivation of the MGMT gene by promoter methylation was associated with longer survival (P = 0.0051; Log-rank test). At 18 months, survival was 62% (16 of 26) for patients testing positive for a methylated MGMT promoter but reached only 8% (1 of 12) in absence of methylation (P = 0.002; Fisher's exact test). In the presence of other clinically relevant factors, methylation of the MGMT promoter remains the only significant predictor (P = 0.017; Cox regression). CONCLUSIONS: This prospective clinical trial identifies MGMT-methylation status as an independent predictor for glioblastoma patients treated with a methylating agent. The association of the epigenetic inactivation of the DNA repair gene MGMT with better outcome in this homogenous cohort may have important implications for the design of future trials and supports efforts to deplete MGMT by O-6-benzylguanine, a noncytotoxic substrate of this enzyme.
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Limited antimicrobial agents are available for the treatment of implant-associated infections caused by fluoroquinolone-resistant Gram-negative bacilli. We compared the activities of fosfomycin, tigecycline, colistin, and gentamicin (alone and in combination) against a CTX-M15-producing strain of Escherichia coli (Bj HDE-1) in vitro and in a foreign-body infection model. The MIC and the minimal bactericidal concentration in logarithmic phase (MBC(log)) and stationary phase (MBC(stat)) were 0.12, 0.12, and 8 μg/ml for fosfomycin, 0.25, 32, and 32 μg/ml for tigecycline, 0.25, 0.5, and 2 μg/ml for colistin, and 2, 8, and 16 μg/ml for gentamicin, respectively. In time-kill studies, colistin showed concentration-dependent activity, but regrowth occurred after 24 h. Fosfomycin demonstrated rapid bactericidal activity at the MIC, and no regrowth occurred. Synergistic activity between fosfomycin and colistin in vitro was observed, with no detectable bacterial counts after 6 h. In animal studies, fosfomycin reduced planktonic counts by 4 log(10) CFU/ml, whereas in combination with colistin, tigecycline, or gentamicin, it reduced counts by >6 log(10) CFU/ml. Fosfomycin was the only single agent which was able to eradicate E. coli biofilms (cure rate, 17% of implanted, infected cages). In combination, colistin plus tigecycline (50%) and fosfomycin plus gentamicin (42%) cured significantly more infected cages than colistin plus gentamicin (33%) or fosfomycin plus tigecycline (25%) (P < 0.05). The combination of fosfomycin plus colistin showed the highest cure rate (67%), which was significantly better than that of fosfomycin alone (P < 0.05). In conclusion, the combination of fosfomycin plus colistin is a promising treatment option for implant-associated infections caused by fluoroquinolone-resistant Gram-negative bacilli.
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INTRODUCTION: Video records are widely used to analyze performance in alpine skiing at professional or amateur level. Parts of these analyses require the labeling of some movements (i.e. determining when specific events occur). If differences among coaches and differences for the same coach between different dates are expected, they have never been quantified. Moreover, knowing these differences is essential to determine which parameters reliable should be used. This study aimed to quantify the precision and the repeatability for alpine skiing coaches of various levels, as it is done in other fields (Koo et al, 2005). METHODS: A software similar to commercialized products was designed to allow video analyses. 15 coaches divided into 3 groups (5 amateur coaches (G1), 5 professional instructors (G2) and 5 semi-professional coaches (G3)) were enrolled. They were asked to label 15 timing parameters (TP) according to the Swiss ski manual (Terribilini et al, 2001) for each curve. TP included phases (initiation, steering I-II), body and ski movements (e.g. rotation, weighting, extension, balance). Three video sequences sampled at 25 Hz were used and one curve per video was labeled. The first video was used to familiarize the analyzer to the software. The two other videos, corresponding to slalom and giant slalom, were considered for the analysis. G1 realized twice the analysis (A1 and A2) at different dates and TP were randomized between both analyses. Reference TP were considered as the median of G2 and G3 at A1. The precision was defined as the RMS difference between individual TP and reference TP, whereas the repeatability was calculated as the RMS difference between individual TP at A1 and at A2. RESULTS AND DISCUSSION: For G1, G2 and G3, a precision of +/-5.6 frames, +/-3.0 and +/-2.0 frames, was respectively obtained. These results showed that G2 was more precise than G1, and G3 more precise than G2, were in accordance with group levels. The repeatability for G1 was +/-3.1 frames. Furthermore, differences among TP precision were observed, considering G2 and G3, with largest differences of +/-5.9 frames for "body counter rotation movement in steering phase II", and of 0.8 frame for "ski unweighting in initiation phase". CONCLUSION: This study quantified coach ability to label video in term of precision and repeatability. The best precision was obtained for G3 and was of +/-0.08s, which corresponds to +/-6.5% of the curve cycle. Regarding the repeatability, we obtained a result of +/-0.12s for G1, corresponding to +/-12% of the curve cycle. The repeatability of G2 and G3 are expected to be lower than the precision of G1 and the corresponding repeatability will be assessed soon. In conclusion, our results indicate that the labeling of video records is reliable for some TP, whereas caution is required for others. REFERENCES Koo S, Gold MD, Andriacchi TP. (2005). Osteoarthritis, 13, 782-789. Terribilini M, et al. (2001). Swiss Ski manual, 29-46. IASS, Lucerne.
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A large variety of cancer vaccines have undergone extensive testing in early-phase clinical trials. A limited number have also been tested in randomized phase II clinical trials. Encouraging trends toward increased survival in the vaccine arms have been recently observed for 2 vaccine candidates in patients with non-small-cell lung cancer. These have provided the impetus for the initiation of phase III trials in large groups of patients with lung cancer. These vaccines target 2 antigens widely expressed in lung carcinomas: melanoma-associated antigen 3, a cancer testis antigen; and mucin 1, an antigen overexpressed in a largely deglycosylated form in advanced tumors. Therapeutic cancer vaccines aim at inducing strong CD8 and CD4 T-cell responses. The majority of vaccines recently tested in phase I clinical trials show efficacy in terms of induction of specific tumor antigen immunity. However, clinical efficacy remains to be determined but appears limited. Efforts are thus aimed at understanding the basis for this apparent lack of effect on tumors. Two major factors are involved. On one hand, current vaccines are suboptimal. Strong adjuvant agents and appropriate tumor antigens are needed. Moreover, dose, route, and schedule also need optimization. On the other hand, it is now clear that large tumors often present a tolerogenic microenvironment that hampers effective antitumor immunity. The partial understanding of the molecular pathways leading to functional inactivation of T cells at tumor sites has provided new targets for intervention. In this regard, blockade of cytotoxic T-lymphocyte antigen-4 and programmed death-1 with humanized monoclonal antibodies has reached the clinical testing stage. In the future, more potent cancer vaccines will benefit from intense research in antigen discovery and adjuvant agents. Furthermore, it is likely that vaccines need to be combined with compounds that reverse major tolerogenic pathways that are constitutively active at the tumor site. Developing these combined approaches to vaccination in cancer promises new, exciting findings and, at the same time, poses important challenges to academic research institutions and the pharmaceutical industry.
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Ga(3+) is a semimetal element that competes for the iron-binding sites of transporters and enzymes. We investigated the activity of gallium maltolate (GaM), an organic gallium salt with high solubility, against laboratory and clinical strains of methicillin-susceptible Staphylococcus aureus (MSSA), methicillin-resistant S. aureus (MRSA), methicillin-susceptible Staphylococcus epidermidis (MSSE), and methicillin-resistant S. epidermidis (MRSE) in logarithmic or stationary phase and in biofilms. The MICs of GaM were higher for S. aureus (375 to 2000 microg/ml) than S. epidermidis (94 to 200 microg/ml). Minimal biofilm inhibitory concentrations were 3,000 to >or=6,000 microg/ml (S. aureus) and 94 to 3,000 microg/ml (S. epidermidis). In time-kill studies, GaM exhibited a slow and dose-dependent killing, with maximal action at 24 h against S. aureus of 1.9 log(10) CFU/ml (MSSA) and 3.3 log(10) CFU/ml (MRSA) at 3x MIC and 2.9 log(10) CFU/ml (MSSE) and 4.0 log(10) CFU/ml (MRSE) against S. epidermidis at 10x MIC. In calorimetric studies, growth-related heat production was inhibited by GaM at subinhibitory concentrations; and the minimal heat inhibition concentrations were 188 to 4,500 microg/ml (MSSA), 94 to 1,500 microg/ml (MRSA), and 94 to 375 microg/ml (MSSE and MRSE), which correlated well with the MICs. Thus, calorimetry was a fast, accurate, and simple method useful for investigation of antimicrobial activity at subinhibitory concentrations. In conclusion, GaM exhibited activity against staphylococci in different growth phases, including in stationary phase and biofilms, but high concentrations were required. These data support the potential topical use of GaM, including its use for the treatment of wound infections, MRSA decolonization, and coating of implants.
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Abstract : Host-Cell Factor 1 (HCF-1) was first discovered in the study of the herpes simplex virus (HSV) infection. HCF-1 is one of the two cellular proteins that compose the VP16-induced complex, a key activator of HSV lytic infection. lncleed, when HSV infects human cells, it is able to enter two modes of infection: lytic or latent. The V`P16-induced complex promotes the lytic mode and in so doing the virus targets important cellular regulatory proteins, such as HCF-1, to manipulate the status of the infected cell. Indeed, HCF-1 regulates human cell proliferation and the cell cycle at different steps. In human, HCF-1 is unusual in that it undergoes a process of proteolytic maturation that results from cleavages at six centrally located 26 amino acid repeats called HCF-1pro repeats. This generates a heterodimeric complex of stably associated amino- (HCF-1n) and carboxy- (HCF-1c) terminal subunits. The absence of the HCF-1 N or HCF-1; subunit leads predominantly to either G1 or M phase defects, respectively. We have hypothesized that HCF-1 forms a heterodimeric complex to permit communication between the two subunits of HCF-1 involved in regulating different phases of the cell cycle. Indeed, there is evidence for such inter-subunit communication because a point mutation called P134S in the HCF-1N subunit in the temperature-sensitive hamster cell line tsBN67 causes, addition to G1- phase defects associated with the HCF-1n subunit, M-phase defects similar to the defects seen upon loss of HCF-1 function. Furthermore, inhibition of the proteolytic maturation of HCF-1 by deletion of the six HCF-1pro repeats (HCF-1Aimo) also leads to M-phase defects, specifically cytokinesis defects leading to binucleation, indicating that there is loss of HCF-15 function in the absence of HCF-1 maturation. I demonstrate that individual point mutations in each of the six HCF-1pro repeats that prevent HCF-1 proteolytic maturation also lead to binucleation; however, this defect can be latgely rescued by the presence of just one HCF-1pRO sequence in I-ICF»1. These results argue that processing itself is important for the HCF-1g function. In fact, until now, the hypothesis was that the proteolytic processing per se is more important for HCF-1C function than the proteolytic processing region. But I show that processing per se is not sufticient to rescue multinucleation, but that the HCF-lpm sequence itself is crucial. This discovery leads to the conclusion that the I-ICF-1pRO repeats have an additional function important for HCF-le function. From the studies of others, one potential function of the HCF-lrxo tepeats is as a binding site for O-link NAcetyl glycosamine tansferase (OGT) to glycosylate an HCF-1n-sunbunit region called the Basic region. This new function suggests the Basic region of HCF-1n is also implicated in the communication between the two subunits. This inter-subunit communication was analyzed in more detail with the studies of the Pl34S mutation and the residues 382-450 region of HCF-l that when removed prevents HCF-l subunit association. I demonstrate that the point mutation also leads to a binucleation defect in Hela cells as well as in the tsBN67 cells. In addition, the effect of this mutation on the regulation of HCF-1c activity seems to interfere with that of the HCF-lpgg repeats because the sum of the deletion of the proteolytic processing region and the point mutation surprisingly leads to re-establishment of correct cytokinesis. The study of the 382-450 HCF-lN region also yielded surprising results. This region important for the association of the two subunits is also important for both HCF-1c function in M phase and G1 phase progression. Thus, I have discovered two main functions of this region: its role in the regulation of HCF-lc function in M phase and its involvement in the regulation of G1/S phase ?- an HCF-1n function. These results support the importance of inter-subunit communication in HCF-1 functions. My research illuminates the understanding of the interaction of the two subunits by showing that the whole HCF-1n subunit is involved in the inter-subunit communication in order to regulate HCF-1c function. For this work, I was concentrated on the study of cytokinesis; the first phenotype showing the role of HCF-1c in the M phase. Then, I extended the study of the M phase with analysis of steps earlier to cytokinesis. Because some defects in the chromosome segregation was already described in the absence of HCF-1, I decided to continue the study of M phase by checking effects on the chromosome segregation. I showed that the HCF-1n subunit and HCF-1pro repeats are both important for this key step of M phase. I show that the binucleation phenotype resulting from deletion or mutation in HCF-1pro repeats, Pl34S point mutation or the lack of the region 382-450 are correlated with micronuclei, and chromosome segregation and alignment defects. This suggests that HCF«lç already regulates M phase during an early step and could be involved in the complex regulation of chromosome segregation. Because one of the major roles of HCF-1 is to be a transcription regulator, I also checked the capacity of HCF-1 to bind to the chromatin in my different cell lines. All my recombinant proteins can bind the chromatin, except for, as previously described, the HCF-1 with the P134S point mutation, This suggests that the binding of HCF-1 to the chromatin is not dependant to the Basic and proteolytic regions but more to the Kelch domain. Thus, if the function of HCF-ig in M phase is dependant to its chromatin association, the intercommunication and the proteolytic region are not involved in the ability to bind to the chromatin but more to bind to the right place of the chromatin or to be associated with the co-factors. Résumé : L'étude de l'infection par le virus Herpes Simplex (HSV) a permis la découverte de la protéine HCF-1 (Host-Cell Factor). HCF-1 est une des protéines cellulaires qui font partie du complexe induit par VP16 ; ce complexe est la clef pour l'activation de la phase lytique de HSV. Afin de manipuler les cellules infectées, le complexe induit pas le VPIG devrait donc cibler les protéines importantes pour la régulation cellulaire, telles que la protéine HCF-1. Cette dernière s'avère donc être un senseur pour la cellule et devrait également jouer un rôle de régulation lors des différentes phases du cycle cellulaire. Chez l'humain, HCF-1 a la particularité de devoir passer par une phase de maturation pour devenir active. Lors de cette maturation, la protéine subit une coupure protéolytique au niveau de six répétitions composées de 26 acides aminés, appelé HCF-1pro repeats. Cette coupure engendre la formation d'un complexe formé de deux sous-unités, HCF-1n et HCF-1c, associées l'une à l'autre de façon stable. Enlever la sous-unité HCF-IN ou C entraîne respectivement des défauts dans la phase G1 et M. Nous pensons donc que HCF-1 forme un complexe hétérodimérique afin de permettre la communication entre les molécules impliquées dans la régulation des différentes phases du cycle cellulaire. Cette hypothèse est déduite suite à deux études: l'une réalisée sur la lignée cellulaire tsBN67 et l'autre portant sur l'inhibition de la maturation protéolytique. La lignée cellulaire tsBN67, sensible à la température, porte la mutation Pl 345 dans la sous-unité HCF-1n. Cette mutation, en plus d'occasionner des défauts dans la phase G1 (défauts liés à la sous-unité HCF-1N), a aussi pour conséquence d'entrainer des défauts dans la phase M, défauts similaires à ceux dus a la perte de la sous-unité HCF-1c. Quant à la maturation protéolytique, l'absence de la région de la protéolyse provoque la binucléation, défaut lié à la cytokinèse, indiquant la perte de la fonction de la sous-unité HCF-1c. Au cours de ma thèse, j'ai démontré que des mutations dans les HCF-1=no repeats, qui bloquent la protéolyse, engendrent la binucléation ; cependant ce défaut peut être corrigé pas l'ajout d'un HCF-1pro repeat dans un HCF-1 ne contenant pas la région protéolytique. Ces résultats soutiennent l'idée que la région protéolytique est importante pour le bon fonctionnement de HCF-1c. En réalité jusqu'a maintenant on supposait que le mécanisme de coupure était plus important que la région impliquée pour la régulation de la fonction de HCF-1;. Mais mon étude montre que la protéolyse n'est pas suffisante pour éviter la binucléation ; en effet, les HCF-1pro repeats semblent jouer le rôle essentiel dans le cycle cellulaire. Cette découverte conduit à la conclusion que les HCF-1pro repeats ont sûrement une fonction autre qui serait cruciale pour la foncton de HCF-1c. Une des fonctions possibles est d'être le site de liaison de l'O-linked N-acetylglucosamine transférase (OGT) qui glycosylerait la région Basique de HCF-1n. Cette nouvelle fonction suggère que la région Basique est aussi impliquée dans la communication entre les deux sous- unités. L'intercommunication entre les deux sous-unités ai été d'ailleurs analysée plus en détail dans mon travail à travers l'étude de la mutation Pl34S et de la région 382-450, essentielle pour l'association des deux sous»unités. J'ai ainsi démontré que la mutation P134S entraînait aussi des défauts dans la cytokinése dans la lignée cellulaire Hela, de plus, son influence sur HCF-1c semble interférer avec celle de la région protéolytique. En effet, la superposition de ces deux modifications dans HCF-1 conduit au rétablissement d'une cytokinése correcte. Concernant la région 382 à 450, les résultats ont été assez surprenants, la perte de cette région provoque l'arrêt du cycle en G1 et la binucléation, ce qui tend à prouver son importance pour le bon fonctionnement de HCF-1n et de HCF-1c. Cette découverte appuie par conséquent l'hypotl1èse d'une intercommunicatzion entre les deux sous-unités mettant en jeu les différentes régions de HCF-1n. Grâce à mes recherches, j'ai pu améliorer la compréhension de l'interaction des deux sous-unités de HCF-1 en montrant que toutes les régions de HCF-1n sont engagées dans un processus d'intercommunication, dont le but est de réguler l'action de HCF-1c. J'ai également mis en évidence une nouvelle étape de la maturation de HCF-1 qui représente une phase importante pour l'activation de la fonction de HCF-1c. Afin de mettre à jour cette découverte, je me suis concentrée sur l'étude de l'impact de ces régions au niveau de la cytokinése qui fut le premier phénotype démontrant le rôle de HCF-1c dans la phase M. A ce jour, nous savons que HCF-1c joue un rôle dans la cytokinèse, nous ne connaissons pas encore sa fonction précise. Dans le but de cerner plus précisément cette fonction, j'ai investigué des étapes ultérieures ai la cytokinèse. Des défauts dans la ségrégation des chromosomes avaient déjà été observés, ai donc continué l'étude en prouvant que HCF-1n et les HCF-1pro repeats sont aussi importants pour le bon fonctionnement de cette étape clef également régulée par HCF-1c. J' ai aussi montré que la région 382-450 et la mutation P134S sont associées à un taux élevé de micronoyaux, de défauts dans la ségrégation des chromosomes. L'une des fonctions principales de HCF-1 étant la régulation de la transcription, j'ai aussi contrôlé la capacité de HCF-1 à se lier à la chromatine après insertion de mutations ou délétions dans HCF-1n et dans la région protéolytique. Or, à l'exception des HCF-1 contenant la mutation P134S, la sous-unité HCF-1c des HCF-1 tronquées se lie correctement à la chromatine. Cette constatation suggère que la liaison entre HCF-1c et chromatine n'est pas dépendante de la région Basique ou Protéolytique mais peut-être vraisemblablement de la région Kelch. Donc si le rôle de HCF-1c est dépendant de sa capacité â activer la transcription, l'intercommunication entre les deux sous-unités et la région protéolytique joueraient un rôle important non pas dans son habileté à se lier à la chromatine, mais dans la capacité de HCF-1 à s'associer aux co-facteurs ou à se placer sur les bonnes régions du génome.
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Introduction: The Thalidomide-Dexamethasone (TD) regimen has provided encouraging results in relapsed MM. To improve results, bortezomib (Velcade) has been added to the combination in previous phase II studies, the so called VTD regimen. In January 2006, the European Group for Blood and Marrow Transplantation (EBMT) and the Intergroupe Francophone du Myélome (IFM) initiated a prospective, randomized, parallel-group, open-label phase III, multicenter study, comparing VTD (arm A) with TD (arm B) for MM patients progressing or relapsing after autologous transplantation. Patients and Methods: Inclusion criteria: patients in first progression or relapse after at least one autologous transplantation, including those who had received bortezomib or thalidomide before transplant. Exclusion criteria: subjects with neuropathy above grade 1 or non secretory MM. Primary study end point was time to progression (TTP). Secondary end points included safety, response rate, progression-free survival (PFS) and overall survival (OS). Treatment was scheduled as follows: bortezomib 1.3 mg/m2 was given as an i.v bolus on Days 1, 4, 8 and 11 followed by a 10-Day rest period (days 12 to 21) for 8 cycles (6 months) and then on Days 1, 8, 15, 22 followed by a 20-Day rest period (days 23 to 42) for 4 cycles (6 months). In both arms, thalidomide was scheduled at 200 mg/Day orally for one year and dexamethasone 40 mg/Day orally four days every three weeks for one year. Patients reaching remission could proceed to a new stem cell harvest. However, transplantation, either autologous or allogeneic, could only be performed in patients who completed the planned one year treatment period. Response was assessed by EBMT criteria, with additional category of near complete remission (nCR). Adverse events were graded by the NCI-CTCAE, Version 3.0.The trial was based on a group sequential design, with 4 planned interim analyses and one final analysis that allowed stopping for efficacy as well as futility. The overall alpha and power were set equal to 0.025 and 0.90 respectively. The test for decision making was based on the comparison in terms of the ratio of the cause-specific hazards of relapse/progression, estimated in a Cox model stratified on the number of previous autologous transplantations. Relapse/progression cumulative incidence was estimated using the proper nonparametric estimator, the comparison was done by the Gray test. PFS and OS probabilities were estimated by the Kaplan-Meier curves, the comparison was performed by the Log-Rank test. An interim safety analysis was performed when the first hundred patients had been included. The safety committee recommended to continue the trial. Results: As of 1st July 2010, 269 patients had been enrolled in the study, 139 in France (IFM 2005-04 study), 21 in Italy, 38 in Germany, 19 in Switzerland (a SAKK study), 23 in Belgium, 8 in Austria, 8 in the Czech republic, 11 in Hungary, 1 in the UK and 1 in Israel. One hundred and sixty nine patients were males and 100 females; the median age was 61 yrs (range 29-76). One hundred and thirty six patients were randomized to receive VTD and 133 to receive TD. The current analysis is based on 246 patients (124 in arm A, 122 in arm B) included in the second interim analysis, carried out when 134 events were observed. Following this analysis, the trial was stopped because of significant superiority of VTD over TD. The remaining patients were too premature to contribute to the analysis. The number of previous autologous transplants was one in 63 vs 60 and two or more in 61 vs 62 patients in arm A vs B respectively. The median follow-up was 25 months. The median TTP was 20 months vs 15 months respectively in arm A and B, with cumulative incidence of relapse/progression at 2 years equal to 52% (95% CI: 42%-64%) vs 70% (95% CI: 61%-81%) (p=0.0004, Gray test). The same superiority of arm A was also observed when stratifying on the number of previous autologous transplantations. At 2 years, PFS was 39% (95% CI: 30%-51%) vs 23% (95% CI: 16%-34%) (A vs B, p=0.0006, Log-Rank test). OS in the first two years was comparable in the two groups. Conclusion: VTD resulted in significantly longer TTP and PFS in patients relapsing after ASCT. Analysis of response and safety data are on going and results will be presented at the meeting.
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OBJECTIVE: To assess health-related quality of life (HRQOL) in abatacept-treated children/adolescents with juvenile idiopathic arthritis (JIA). METHODS: In this phase III, double-blind, placebo-controlled trial, subjects with active polyarticular course JIA and an inadequate response/intolerance to ≥1 disease-modifying antirheumatic drug (including biologics) received abatacept 10 mg/kg plus methotrexate (MTX) during the 4-month open-label period (period A). Subjects achieving the American College of Rheumatology Pediatric 30 criteria for improvement (defined "responders") were randomized to abatacept or placebo (plus MTX) in the 6-month double-blind withdrawal period (period B). HRQOL assessments included 15 Child Health Questionnaire (CHQ) health concepts plus the physical (PhS) and psychosocial summary scores (PsS), pain (100-mm visual analog scale), the Children's Sleep Habits Questionnaire, and a daily activity participation questionnaire. RESULTS: A total of 190 subjects from period A and 122 from period B were eligible for analysis. In period A, there were substantial improvements across all of the CHQ domains (greatest improvement was in pain/discomfort) and the PhS (8.3 units) and PsS (4.3 units) with abatacept. At the end of period B, abatacept-treated subjects had greater improvements versus placebo in all domains (except behavior) and both summary scores. Similar improvement patterns were seen with pain and sleep. For participation in daily activities, an additional 2.6 school days/month and 2.3 parents' usual activity days/month were gained in period A responders with abatacept, and further gains were made in period B (1.9 versus 0.9 [P = 0.033] and 0.2 versus -1.3 [P = 0.109] school days/month and parents' usual activity days/month, respectively, in abatacept- versus placebo-treated subjects). CONCLUSION: Improvements in HRQOL were observed with abatacept, providing real-life tangible benefits to children with JIA and their parents/caregivers.
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Bridge deck expansion joints are used to allow for movement of the bridge deck due to thermal expansion, dynamics loading, and other factors. More recently, expansion joints have also been utilized to prevent the passage of winter de-icing chemicals and other corrosives applied to bridge decks from penetrating and damaging substructure components of the bridge. Expansion joints are often one of the first components of a bridge deck to fail and repairing or replacing expansion joints are essential to extending the life of any bridge. In the Phase I study, the research team focused on the current means and methods of repairing and replacing bridge deck expansion joints. Research team members visited with Iowa Department of Transportation (DOT) Bridge Crew Leaders to document methods of maintaining and repairing bridge deck expansion joints. Active joint replacement projects around Iowa were observed to document the means of replacing expansion joints that were beyond repair, as well as, to identify bottlenecks in the construction process that could be modified to decrease the length of expansion joint replacement projects. After maintenance and replacement strategies had been identified, a workshop was held at the Iowa State Institute for Transportation to develop ideas to better maintain and replace expansion joints. Maintenance strategies were included in the discussion as a way to extend the useful life of a joint, thus decreasing the number of joints replaced in a year and reducing the traffic disruptions.