85 research outputs found
: Tubulin dimer binding proteins
International audienceMicrotubules play an essential role in eukaryotic cells, where they perform a wide variety of functions. In this paper, we describe the characterization of proteins associated to tubulin dimer in its native form, using affinity chromatography and mass spectrometry. We used an immunoaffinity column with coupled-monoclonal antibody directed against the alpha-tubulin C-terminus. Tubulin was first loaded onto the column, then interphase and mitotic cell lysates were chromatographed. Tubulin-binding proteins were eluted using a peptide mimicking the alpha-tubulin C-terminus. Elution fractions were analyzed by SDS-PAGE, and a total of 14 proteins were identified with high confidence by mass spectrometry. These proteins could be grouped in four classes: known tubulin-binding proteins, one microtubule-associated protein, heat shock proteins, and proteins that were not shown previously to bind tubulin dimer or microtubules
Apport de l'épidémiologie dans le choix des outils d'aide à la prise de décision sanitaire en santé animale. (Evaluation des tests de dépistage en santé animale)
L étude et le choix des stratégies décisionnelles en santé animale nécessite de disposer d informations sur l efficacité des outils disponibles, qu il s agisse d un test unique, d une association de plusieurs tests ou d un ensemble de critères cliniques et épidémiologiques. La validation des tests de dépistage ou de diagnostic constitue donc un prérequis à la conception de protocoles d aide à la prise de décisions sanitaires. Lorsqu il existe une référence fournissant une information sur le statut infectieux des individus étudiés, l estimation des caractéristiques des tests peut être effectuée de manière directe. En santé animale, il est toutefois fréquent de ne pas disposer de cette information, lorsqu aucun test ne référence n est disponible ou lorsqu il n a pas pu être mis en œuvre, pour des raisons pratiques, économiques ou éthiques. Dans ce cas, l étude des tests requiert l utilisation de méthodes statistiques adaptées, telles l utilisation de modèles à classe latente implémentés par une approche bayésienne. Nous avons choisi, au cours de nos travaux, de nous intéresser à l estimation de la part d incertitude liée à l utilisation de tests en tant qu outils d aide à la prise de décision. Nous exposons dans un premier chapitre les enjeux et les modalités de la lutte contre les maladies animales, les outils épidémiologiques disponibles pour l élaboration de stratégies décisionnelles et les méthodes permettant l évaluation de ces outils et leur comparaison. Les trois chapitres suivants constituent une application de ces méthodes, dans des contextes différents correspondant à trois types de situations dans lesquelles il existe un besoin d aide à la décision sanitaire en santé animale : le dépistage de la brucellose porcine chez les porcs reproducteurs, le dépistage de l épididymite contagieuse du bélier chez les béliers destinés à l export et le dépistage de la tuberculose bovine dans les départements de Côte d Or et de Dordogne et dans la région camarguaise. Le dernier chapitre de ce manuscrit consiste en une discussion générale sur les modalités de choix d un outil d aide à la décision sanitaire.Knowing the efficacy of a diagnostic tool, whether it is a test used alone, a sequence of several tests or a group of clinical criteria, is essential to study and choose decision strategies. The validation of diagnostic and screening tests is thus necessary to conceive decision schemes. When a gold standard is available, the characteristics of a test can be estimated directly. However, the true individual disease status of the animals is often unknown, particularly in absence of a gold standard or when the gold standard cannot be used because of economical, practical or ethical constraints. In these cases, specific statistical methods like latent class models implemented through a Bayesian approach must be used. Our work aimed at estimating the uncertainty due to the use of diagnostic tests as decision tools. The first chapter presents the issues and practical details of the struggle against animal disease and the epidemiological tools available to estimate the characteristics of the tests and to compare them. In the three following chapters, these methods are applied to three different contexts in which the conception and the evaluation of decision tools are needed: the screening of porcine brucellosis in breeding hogs, the screening of Brucella ovis infection in exported rams and the screening of bovine tuberculosis in Côte d Or, Dordogne and Camargue (France). The last chapter consists in a global discussion about how to choose a decision tool.PARIS11-SCD-Bib. électronique (914719901) / SudocSudocFranceF
Utility of Quantitative 99mTc-MAA SPECT/CT for 90yttrium-Labelled Microsphere Treatment Planning: Calculating Vascularized Hepatic Volume and Dosimetric Approach
Objectives. The
aim of this study was to assess the
effectiveness of SPECT/CT for volume
measurements and to report a case illustrating
the major impact of SPECT/CT in calculating the
vascularized liver volume and dosimetry prior to
injecting radiolabelled yttrium-90 microspheres
(Therasphere). Materials and
Methods. This was a phantom study,
involving volume measurements carried out by two
operators using SPECT and SPECT/CT images. The
percentage of error for each method was
calculated, and interobserver reproducibility
was evaluated. A treatment using
Therasphere was planned in a patient
with three hepatic arteries, and the
quantitative analysis of SPECT/CT for this
patient is provided. Results.
SPECT/CT volume measurements proved to be
accurate (mean error <6% for volumes
≥16 cm3) and
reproductive (interobserver agreement = 0.9). In the case report, 99mTc-MAA SPECT/CT identified a large liver volume, not
previously identified with angiography, which was shown to be
vascularized after selective MAA injection into an arterial
branch, resulting in a large modification in the activity of
Therasphere used. Conclusions. MAA
SPECT/CT is accurate for vascularized liver volume measurements,
providing a valuable contribution to the therapeutic planning of
patients with complex hepatic vascularization
At-Risk Phenotype of Neurofibromatose-1 Patients: A Multicentre Case-Control Study
<p>Abstract</p> <p>Objectives</p> <p>To assess associations between subcutaneous neurofibromas (SC-NFs) and internal neurofibromas in patients with neurofibromatosis type 1 (NF-1) and to determine whether the association between SC-NFs and peripheral neuropathy was ascribable to internal neurofibromas.</p> <p>Patients and methods</p> <p>Prospective multicentre case-control study. Between 2005 and 2008, 110 NF-1 adults having two or more SC-NFs were individually matched for age, sex and hospital with 110 controls who had no SC-NF. Patients underwent standardized MRI of the spinal cord, nerve roots and sciatic nerves and an electrophysiological study. Analyses used adjusted multinomial logistic regression (ORa) to estimate the risk of the presence of internal neurofibromas or peripheral neuropathies associated with patients presented 2 to 9 SC-NFs, at least 10 SC-NFs as compared to patients without any (referential category).</p> <p>Results</p> <p>Cases had a mean age of 41 (± 13) years; 85 (80%) had two to nine SC-NFs and 21 (19%) at least ten SC-NFs. SC-NFs were more strongly associated with internal neurofibromas in patients with ten or more SC-NFs than in patients with fewer NF-SCs (e.g., sciatic nerve, aOR = 29.1 [8.5 to 100] vs. 4.3 [2.1 to 9.0]). The association with SC-NFs was stronger for diffuse, intradural, and > 3 cm internal neurofibromas than with other internal neurofibromas. Axonal neuropathy with slowed conduction velocities (SCV) was more strongly associated with having at least ten SC-NFs (aOR = 29.9, 5.5 to 162.3) than with having fewer SC-NFs (aOR = 4.4, 0.9 to 22.0). Bivariate analyses showed that the association between axonal neuropathy with SCV and sciatic neurofibromas was mediated by the association between SC-NFs and sciatic neurofibromas.</p> <p>Conclusion</p> <p>The at-risk phenotype of NF-1 patients (i.e. NF-1 patients with SC-NFs) is ascribable to associations linking SC-NFs to internal neurofibromas at risk for malignant transformation and to axonal neuropathies with slowed conduction velocities. Axonal neuropathies with SCV are particularly common in patients with at least ten SC-NFs.</p> <p>Registration details</p> <p>ORPHA86301</p
Randomized Phase Iii Study Comparing Paclitaxel-bleomycin, Etoposide, And Cisplatin (bep) To Standard Bep In Intermediate-prognosis Germ-cell Cancer: Intergroup Study Eortc 30983
Purpose: To compare the efficacy of four cycles of paclitaxel-bleomycin, etoposide, and cisplatin (T-BEP) to four cycles of bleomycin, etoposide, and cisplatin (BEP) in previously untreated patients with intermediate-prognosis germ-cell cancer (GCC). Patients and Methods: Patients were randomly assigned to receive either T-BEP or standard BEP. Patients assigned to the T-BEP group received paclitaxel 175 mg/m(2) in a 3-hour infusion. Patients who were administered T-BEP received primary granulocyte colony-stimulating factor (G-CSF) prophylaxis. The study was designed as a randomized open-label phase II/III study. To show a 10% improvement in 3-year progression-free survival (PFS), the study aimed to recruit 498 patients but closed with 337 patients as a result of slow accrual. Results: Accrual was from November 1998 to April 2009. A total of 169 patients were administered BEP, and 168 patients were administered T-BEP. Thirteen patients in both arms were ineligible, mainly as a result of a good prognosis of GCC (eight patients administered BEP; six patients administered T-BEP) or a poor prognosis of GCC (one patient administered BEP; four patients administered T-BEP). PFS at 3 years (intent to treat) was 79.4% in the T-BEP group versus 71.1% in the BEP group (hazard ratio [HR], 0.73; CI, 0.47 to 1.13; P [log-rank test] = 0.153). PFS at 3 years in all eligible patients was 82.7% versus 70.1%, respectively (HR, 0.60; CI: 0.37 to 0.97) and was statistically significant (P = 0.03). Overall survival was not statistically different. Conclusion: T-BEP administered with G-CSF seems to be a safe and effective treatment regimen for patients with intermediate-prognosis GCC. However, the study recruited a smaller-than-planned number of patients and included 7.7% ineligible patients. The primary analysis of the trial could not demonstrate statistical superiority of T-BEP for PFS. When ineligible patients were excluded, the analysis of all eligible patients demonstrated a 12% superior 3-year PFS with T-BEP, which was statistically significant. J Clin Oncol 30: 792-799. (C) 2012 by American Society of Clinical Oncolog
Mortality Associated with Neurofibromatosis 1: A Cohort Study of 1895 Patients in 1980-2006 in France
<p>Abstract</p> <p>Background</p> <p>Neurofibromatosis 1 (NF1), a common autosomal dominant disorder, was shown in one study to be associated with a 15-year decrease in life expectancy. However, data on mortality in NF1 are limited. Our aim was to evaluate mortality in a large retrospective cohort of NF1 patients seen in France between 1980 and 2006.</p> <p>Methods</p> <p>Consecutive NF1 patients referred to the National French Referral Center for Neurofibromatoses were included. The standardized mortality ratio (SMR) with its 95% confidence interval (CI) was calculated as the ratio of observed over expected numbers of deaths. We studied factors associated with death and causes of death.</p> <p>Results</p> <p>Between 1980 and 2006, 1895 NF1 patients were seen. Median follow-up was 6.8 years (range, 0.4-20.6). Vital status was available for 1226 (65%) patients, of whom 1159 (94.5%) survived and 67 (5.5%) died. Overall mortality was significantly increased in the NF1 cohort (SMR, 2.02; CI, 1.6-2.6; <it>P </it>< 10<sup>-4</sup>). The excess mortality occurred among patients aged 10 to 20 years (SMR, 5.2; CI, 2.6-9.3; <it>P </it>< 10<sup>-4</sup>) and 20 to 40 years (SMR, 4.1; 2.8-5.8; <it>P </it>< 10<sup>-4</sup>). Significant excess mortality was found in both males and females. In the 10-20 year age group, females had a significant increase in mortality compared to males (SMR, 12.6; CI, 5.7-23.9; and SMR, 1.8; CI, 0.2-6.4; respectively). The cause of death was available for 58 (86.6%) patients; malignant nerve sheath tumor was the main cause of death (60%).</p> <p>Conclusions</p> <p>We found significantly increased SMRs indicating excess mortality in NF1 patients compared to the general population. The definitive diagnosis of NF1 in all patients is a strength of our study, and the high rate of death related to malignant transformation is consistent with previous work. The retrospective design and hospital-based recruitment are limitations of our study. Mortality was significantly increased in NF1 patients aged 10 to 40 years and tended to be higher in females than in males.</p
Usefulness and pitfalls of MAA SPECT/CT in identifying digestive extrahepatic uptake when planning liver radioembolization
International audiencePURPOSE: Identifying gastroduodenal uptake of (99m)Tc-macroaggregated albumin (MAA), which is associated with an increased risk of ulcer disease, is a crucial part of the therapeutic management of patients undergoing radioembolization for liver tumours. Given this context, the use of MAA single photon emission computed tomography (SPECT)/CT may be essential, but the procedure has still not been thoroughly evaluated. The aim of this retrospective study was to determine the effectiveness of MAA SPECT/CT in identifying digestive extrahepatic uptake, while determining potential diagnostic pitfalls. METHODS: Overall, 139 MAA SPECT/CT scans were performed on 103 patients with different hepatic tumour types. Patients were followed up for at least 6 months according to standard requirements. RESULTS: Digestive, or digestive-like, uptake other than free pertechnetate was identified in 5.7% of cases using planar imaging and in 36.6% of cases using SPECT/CT. Uptake sites identified by SPECT/CT included the gastroduodenal region (3.6%), gall bladder (12.2%), portal vein thrombosis (6.5%), hepatic artery (6.5%), coil embolization site (2.1%) as well as falciform artery (5.0%). For 2.1% of explorations, a coregistration error between SPECT and CT imaging could have led to a false diagnosis by erroneously attributing an uptake site to the stomach or gall bladder, when the uptake actually occurred in the liver. CONCLUSION: SPECT/CT is more efficacious than planar imaging in identifying digestive extrahepatic uptake sites, with extrahepatic uptake observed in one third of scans using the former procedure. However, more than half of the uptake sites in our study were vascular in nature, without therapeutic implications. The risk of coregistration errors must also be kept in mind
A first-in-human study investigating biodistribution, safety and recommended dose of a new radiolabeled MAb targeting FZD10 in metastatic synovial sarcoma patients
Background: Synovial Sarcomas (SS) are rare tumors occurring predominantly in adolescent and young adults with a dismal prognosis in advanced phases. We report a first-in-human phase I of monoclonal antibody (OTSA-101) targeting FZD10, overexpressed in most SS but not present in normal tissues, labelled with radioisotopes and used as a molecular vehicle to specifically deliver radiation to FZD10 expressing SS lesions.
Methods: Patients with progressive advanced SS were included. In the first step of this trial, OTSA-101 in vivo biodistribution and lesions uptake were evaluated by repeated whole body planar and SPECT-CT scintigraphies from H1 till H144 after IV injection of 187 MBq of 111In-OTSA-101. A 2D dosimetry study also evaluated the liver absorbed dose when using 90Y-OTSA-101. In the second step, those patients with significant tumor uptake were randomized between 370 MBq (Arm A) and 1110 MBq (Arm B) of 90Y-OTSA-101 for radionuclide therapy.
Results: From January 2012 to June 2015, 20 pts. (median age 43 years [21–67]) with advanced SS were enrolled. Even though 111In-OTSA-101 liver uptake appeared to be intense, estimated absorbed liver dose was less than 20 Gy for each patient. Tracer intensity was greater than mediastinum in 10 patients consistent with sufficient tumor uptake to proceed to treatment with 90Y-OTSA-101: 8 were randomized (Arm A: 3 patients and Arm B: 5 patients) and 2 were not randomized due to worsening PS. The most common Grade ≥ 3 AEs were reversible hematological disorders, which were more frequent in Arm B. No objective response was observed. Best response was stable disease in 3/8 patients lasting up to 21 weeks for 1 patient.
Conclusions: Radioimmunotherapy targeting FZD10 is feasible in SS patients as all patients presented at least one lesion with 111In-OTSA-101 uptake. Tumor uptake was heterogeneous but sufficient to select 50% of pts. for 90Y-OTSA-101 treatment. The recommended activity for further clinical investigations is 1110 MBq of 90Y-OTSA-101. However, because of hematological toxicity, less energetic particle emitter radioisopotes such as Lutetium 177 may be a better option to wider the therapeutic index.
Trial registration: The study was registered on the NCT01469975 ( https://clinicaltrials.gov/ct2/show/NCT01469975 ) website with a registration code NCT01469975 on November the third, 2011
A computer decision aid for medical prevention: a pilot qualitative study of the Personalized Estimate of Risks (EsPeR) system
BACKGROUND: Many preventable diseases such as ischemic heart diseases and breast cancer prevail at a large scale in the general population. Computerized decision support systems are one of the solutions for improving the quality of prevention strategies. METHODS: The system called EsPeR (Personalised Estimate of Risks) combines calculation of several risks with computerisation of guidelines (cardiovascular prevention, screening for breast cancer, colorectal cancer, uterine cervix cancer, and prostate cancer, diagnosis of depression and suicide risk). We present a qualitative evaluation of its ergonomics, as well as it's understanding and acceptance by a group of general practitioners. We organised four focus groups each including 6–11 general practitioners. Physicians worked on several structured clinical scenari os with the help of EsPeR, and three senior investigators leaded structured discussion sessions. RESULTS: The initial sessions identified several ergonomic flaws of the system that were easily corrected. Both clinical scenarios and discussion sessions identified several problems related to the insufficient comprehension (expression of risks, definition of familial history of disease), and difficulty for the physicians to accept some of the recommendations. CONCLUSION: Educational, socio-professional and organisational components (i.e. time constraints for training and use of the EsPeR system during consultation) as well as acceptance of evidence-based decision-making should be taken into account before launching computerised decision support systems, or their application in randomised trials
Genomic history of the seventh pandemic of cholera in Africa.
The seventh cholera pandemic has heavily affected Africa, although the origin and continental spread of the disease remain undefined. We used genomic data from 1070 Vibrio cholerae O1 isolates, across 45 African countries and over a 49-year period, to show that past epidemics were attributable to a single expanded lineage. This lineage was introduced at least 11 times since 1970, into two main regions, West Africa and East/Southern Africa, causing epidemics that lasted up to 28 years. The last five introductions into Africa, all from Asia, involved multidrug-resistant sublineages that replaced antibiotic-susceptible sublineages after 2000. This phylogenetic framework describes the periodicity of lineage introduction and the stable routes of cholera spread, which should inform the rational design of control measures for cholera in Africa
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