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1.
IEEE Trans Med Imaging ; 43(2): 714-722, 2024 Feb.
Article in English | MEDLINE | ID: mdl-37747861

ABSTRACT

Parallel transmission (pTX) is a versatile solution to enable UHF MRI of the human body, where radiofrequency (RF) field inhomogeneity appears very challenging. Today, state of the art monitoring of the local SAR in pTX consists in evaluating the RF power deposition on specific SAR matrices called Virtual Observation Points (VOPs). It essentially relies on accurate electromagnetic simulations able to return the local SAR distribution inside the body in response to any applied pTX RF waveform. In order to reduce the number of SAR matrices to a value compatible with real time SAR monitoring ( << 103) , a VOP set is obtained by partitioning the SAR model into clusters, and associating a so- called dominant SAR matrix to every cluster. More recently, a clustering-free compression method was proposed, allowing for a significant reduction in the number of SAR matrices. The concept and derivation however assumed static RF shims and their extension to dynamic pTX is not straightforward, thereby casting doubt on the strict validity of the compression approach for these more complicated RF waveforms. In this work, we provide the mathematical framework to tackle this problem and find a rigorous justification of this criterion in the light of convex optimization theory. Our analysis led us to a variant of the clustering-free compression approach exploiting convex optimization. This new compression algorithm offers computational gains for large SAR models and for high-channel count pTX RF coils.


Subject(s)
Algorithms , Data Compression , Humans , Magnetic Resonance Imaging/methods , Radio Waves , Phantoms, Imaging , Computer Simulation
2.
Scand J Rheumatol ; 51(6): 470-480, 2022 11.
Article in English | MEDLINE | ID: mdl-34514929

ABSTRACT

OBJECTIVE: In patients with rheumatoid arthritis (RA) in sustained remission, tapering of biological disease-modifying anti-rheumatic drugs can be considered. Tapering has already been investigated, but its feasibility remains to be determined. Therefore, we explored the feasibility of tapering etanercept in RA in a setting close to practice. METHOD: Patients with RA in 28-joint Disease Activity Score (DAS28) remission (≥ 6 months) and treated with etanercept 50 mg weekly (≥ 1 year) were included in the pragmatic 1 year open-label multicentre randomized controlled TapERA (Tapering Etanercept in Rheumatoid Arthritis) trial. Patients were assigned to continue etanercept weekly or to taper to every other week (EOW). Patients who lost remission [DAS28-C-reactive protein (CRP) ≥ 2.6] were re-escalated to etanercept weekly. The primary outcome was the proportion of patients maintaining DAS28-CRP remission for 6 months. RESULTS: Sixty-six patients were randomized to etanercept weekly (n = 34) or EOW (n = 32). After 6 months, 26/34 patients (76%) in the weekly and 19/32 (59%) in the EOW group maintained disease control (p = 0.136). In the EOW group, 20/32 patients (63%) remained on their tapered treatment during the trial. Two patients reintroduced weekly etanercept themselves. Ten patients were re-escalated to etanercept weekly by the rheumatologist, after a median (interquartile range) interval of 3.0 (2.0-6.0) months. Among these patients, 7/10 regained remission after re-escalation, four of them at the next study visit. CONCLUSIONS: Although non-inferiority could not be demonstrated, tapering of etanercept to EOW appeared feasible in patients in sustained remission.


Subject(s)
Antirheumatic Agents , Arthritis, Rheumatoid , Humans , Etanercept/therapeutic use , Treatment Outcome , Arthritis, Rheumatoid/drug therapy , Antirheumatic Agents/therapeutic use , C-Reactive Protein , Remission Induction
3.
Gynecol Obstet Fertil Senol ; 47(7-8): 562-567, 2019.
Article in French | MEDLINE | ID: mdl-31280032

ABSTRACT

OBJECTIVES: Evaluate an educational program based on "CLEAR" (Cervical Length Education and Review) in the teaching of measuring sonographic cervical length to residents in gynecology and obstetrics. METHODS: This is a prospective cohort study in a tertiary care center between May and November 2017. The residents were asked to collect 5 cervical length images from patients suspected with threatened preterm labor. A theoretical session on cervix measurement image criteria based on "CLEAR" program was taught to all residents. Then, they had to collect 5 new cervical length images. All the images were reviewed by two experienced reviewers, blinded to the resident and whether the image was obtained before or after the theoretical session and based on 8 criteria. RESULTS: Ten residents participated to the study. The mean total score CLEAR was significantly higher post-intervention: 6.6±0.9 vs. 4.3±2.1, positive difference of 2.3±2.3 (P<0.001). Improvement was most significant with the junior residents: 3.6 pre vs. 6.5 post-intervention. CONCLUSION: Educational program based on CLEAR criteria allowed to improve the competence of residents in measuring sonographic cervical length, although this can also be correlated with the progression of residents during the semester. It could be implemented systematically with the aim of CLEAR certification to standardize the teaching of residents in gynecology and obstetrics.


Subject(s)
Cervix Uteri/diagnostic imaging , Gynecology/education , Internship and Residency , Obstetric Labor, Premature/diagnostic imaging , Obstetrics/education , Ultrasonography, Prenatal , Cohort Studies , Female , France , Gestational Age , Humans , Pregnancy , Prospective Studies
4.
Rev Epidemiol Sante Publique ; 67(5): 285-294, 2019 Sep.
Article in French | MEDLINE | ID: mdl-31353238

ABSTRACT

BACKGROUND: A significant proportion of childhood sexual abuse victims suffer from psychological sequelae in adulthood. Factors that provide a better understanding for the reasons why some victims develop these sequelae remain under-explored. In this context, the main objective is to examine the specific contribution of the contextual characteristics of childhood sexual abuse, multitype childhood maltreatment and adolescent suicide attempts on the development of depression and post-traumatic stress disorder in adulthood among sexually abused women as children. A secondary objective aimed to establish the prevalence of various forms of childhood maltreatment, adult onset post-traumatic stress disorder and depression among those women. METHODS: The sample included 479 women victims of childhood sexual abuse who participated in two separate surveys taken by women in the province of Quebec. RESULTS: More than half of these women reported at least one other form of childhood maltreatment, 30% of them presented post-traumatic disorder and 40% suffered from depression in adulthood. Regression analysis indicates that post-traumatic stress disorder was associated with early onset childhood sexual abuse and intergenerational continuity of sexual victimization, as well as childhood physical maltreatment and negligence. Depression was associated with childhood psychological maltreatment and negligence, a non-supportive response following child sexual abuse related disclosure and suicide attempt in adolescence. CONCLUSION: These results confirm the need to consider the cumulative effects of various childhood adversity factors in the psychosocial assessment of sexually abused women in early life, thus helping to better understand and treat their psychological sequelae.


Subject(s)
Adult Survivors of Child Adverse Events , Child Abuse, Sexual , Crime Victims , Depression , Stress Disorders, Post-Traumatic , Adolescent , Adult , Adult Survivors of Child Adverse Events/psychology , Adult Survivors of Child Adverse Events/statistics & numerical data , Aged , Child , Child Abuse/psychology , Child Abuse/statistics & numerical data , Child Abuse, Sexual/psychology , Child Abuse, Sexual/statistics & numerical data , Child, Preschool , Crime Victims/psychology , Crime Victims/statistics & numerical data , Depression/diagnosis , Depression/epidemiology , Depression/etiology , Domestic Violence/psychology , Domestic Violence/statistics & numerical data , Female , Humans , Infant , Infant, Newborn , Life Change Events , Middle Aged , Prevalence , Quebec/epidemiology , Sexual Behavior/psychology , Sexual Behavior/statistics & numerical data , Stress Disorders, Post-Traumatic/diagnosis , Stress Disorders, Post-Traumatic/epidemiology , Stress Disorders, Post-Traumatic/etiology , Stress, Psychological/complications , Stress, Psychological/epidemiology , Stress, Psychological/psychology , Surveys and Questionnaires , Young Adult
5.
Nat Commun ; 10(1): 1449, 2019 03 26.
Article in English | MEDLINE | ID: mdl-30914644

ABSTRACT

The original version of this Article contained an error in the spelling of the authors J. H. Joly and N. A. Graham, which were incorrectly given as J. Jolly and N. Graham. Additionally, the affiliation of both authors with 'Mork Family Department of Chemical Engineering and Materials Science, University of Southern California, Los Angeles, CA 90089' and N. A. Graham with 'Norris Comprehensive Cancer Center, University of Southern California, Los Angeles, CA 90089' was inadvertently omitted. This has now been corrected in both the PDF and HTML versions of the Article.

6.
Nat Commun ; 10(1): 91, 2019 01 09.
Article in English | MEDLINE | ID: mdl-30626875

ABSTRACT

Although numerous therapeutic strategies have attempted to target aerobic glycolysis to inhibit tumor progression, these approaches have not resulted in effective clinical outcomes. Murine squamous cell carcinoma (SCC) can be initiated by hair follicle stem cells (HFSCs). HFSCs utilize aerobic glycolysis, and the activity of lactate dehydrogenase (Ldh) is essential for HFSC activation. We sought to determine whether Ldh activity in SCC is critical for tumorigenesis or simply a marker of the cell type of origin. Genetic abrogation or induction of Ldh activity in HFSC-mediated tumorigenesis shows no effect on tumorigenesis as measured by number, time to formation, proliferation, volume, epithelial to mesenchymal transition, gene expression, or immune response. Ldha-null tumors show dramatically reduced levels of glycolytic metabolites by metabolomics, and significantly reduced glucose uptake by FDG-PET live animal imaging. These results suggest that squamous cancer cells of origin do not require increased glycolytic activity to generate cancers.


Subject(s)
Carcinoma, Squamous Cell/metabolism , L-Lactate Dehydrogenase/metabolism , Neoplasms, Experimental/metabolism , Animals , Enzyme Induction , Female , L-Lactate Dehydrogenase/genetics , Male , Mice , Mice, Transgenic
7.
Anaesthesia ; 72(9): 1159, 2017 09.
Article in English | MEDLINE | ID: mdl-28804879
8.
Sci Rep ; 6: 23523, 2016 Mar 22.
Article in English | MEDLINE | ID: mdl-27002861

ABSTRACT

Aging's most obvious characteristic is the time dependent increase of an individual's probability to die. This lifelong process is accompanied by a large number of molecular and physiological changes. Although numerous genes involved in aging have been identified in the past decades its leading factors have yet to be determined. To identify the very processes driving aging we have developed in the past years an assay to identify physiologically old individuals in a synchronized population of Drosophila melanogaster. Those individuals show an age-dependent increase of intestinal permeability followed by a high risk of death. Here we show that this physiological marker of aging is conserved in 3 invertebrate species Drosophila mojavensis, Drosophila virilis, Caenorhabditis elegans as well as in 1 vertebrate species Danio rerio. Our findings suggest that intestinal barrier dysfunction may be an important event in the aging process conserved across a broad range of species, thus raising the possibility that it may also be the case in Homo sapiens.


Subject(s)
Aging/metabolism , Biological Evolution , Intestines/physiology , Ubiquitin-Protein Ligases/metabolism , Animals , Caenorhabditis elegans , Caenorhabditis elegans Proteins/metabolism , Conserved Sequence , Death , Drosophila , Drosophila Proteins/metabolism , Female , Gene Expression Regulation , Male , Zebrafish , Zebrafish Proteins/metabolism
9.
Scand J Rheumatol ; 45(3): 171-8, 2016.
Article in English | MEDLINE | ID: mdl-26399601

ABSTRACT

OBJECTIVES: Persons who are later diagnosed with early rheumatoid arthritis (ERA) often delay their first contact with a health professional after symptom onset. Besides initial symptoms, psychosocial characteristics of individuals may influence their help-seeking behaviour. We explored the role of disease characteristics, illness perception, and coping in patient-related delay before treatment initiation in recently diagnosed patients with ERA. METHOD: This exploratory, cross-sectional study included 112 patients with ERA from the Care for early RA (CareRA) trial for whom complete data on patient-related delay, coping, and illness perception were available. In addition to baseline sociodemographic and clinical data, the patients' psychosocial profiles were assessed with the Utrecht Coping List (UCL) and the revised Illness Perception Questionnaire (IPQ-R). Correlations were measured by Spearman's rho. Using regression analyses, we weighted the association of variables with patient-related delay. RESULTS: Patient-related delay was positively correlated with perceptions of causality including psychological attributions (r = 0.301, p = 0.001), risk factors (r = 0.189, p = 0.045), immunity (r = 0.261, p = 0.005), and passive coping (r = 0.222, p = 0.018). It was negatively correlated with the 28 swollen joint count (SJC28; r = -0.194, p = 0.040), perceptions of treatment control (r = -0.271, p = 0.004), and illness coherence (r = -0.208, p = 0.028). Clinical and psychosocial variables explained 15% and 18%, respectively, of the variability in patient-related delay. CONCLUSIONS: Aside from a lower SJC, a longer patient-related delay was correlated with a passive coping style, a strong conviction of symptom causality, poor expected treatment control, and a feeling of limited illness coherence. Psychosocial aspects influence individuals' help-seeking behaviour and are worth considering when aiming for a reduction in ERA treatment delay.


Subject(s)
Adaptation, Psychological , Arthritis, Rheumatoid/diagnosis , Attitude to Health , Delayed Diagnosis , Help-Seeking Behavior , Perception , Adult , Arthritis, Rheumatoid/psychology , Cross-Sectional Studies , Female , General Practice , Humans , Male , Middle Aged , Patient Acceptance of Health Care/psychology , Prospective Studies , Risk Factors , Severity of Illness Index , Time Factors
10.
Dermatol Online J ; 21(9)2015 Sep 17.
Article in English | MEDLINE | ID: mdl-26437291

ABSTRACT

In contrast with bone metastasis, acrometastases are uncommon and are associated with advanced cancer. We report the cases of two patients with atypical lesions of the fingers in a context of cancer, in which biopsies confirmed a metastasis. Patients died rapidly before treatment was initiated. We discuss the characteristics of these atypical metastatic sites, associated with a generally poor prognosis.


Subject(s)
Adenocarcinoma, Mucinous/secondary , Bone Neoplasms/secondary , Carcinoma, Squamous Cell/secondary , Fingers , Lung Neoplasms/pathology , Pancreatic Neoplasms/pathology , Skin Neoplasms/secondary , Aged , Bone Neoplasms/diagnostic imaging , Fatal Outcome , Finger Phalanges/diagnostic imaging , Humans , Male , Middle Aged , Radiography
11.
Ann Rheum Dis ; 74(1): 27-34, 2015 Jan.
Article in English | MEDLINE | ID: mdl-25359382

ABSTRACT

OBJECTIVES: To compare the efficacy and safety of intensive combination strategies with glucocorticoids (GCs) in the first 16 weeks (W) of early rheumatoid arthritis (eRA) treatment, focusing on high-risk patients, in the Care in early RA trial. METHODS: 400 disease-modifying antirheumatic drugs (DMARD)-naive patients with eRA were recruited and stratified into high risk or low risk according to classical prognostic markers. High-risk patients (n=290) were randomised to 1/3 treatment strategies: combination therapy for early rheumatoid arthritis (COBRA) Classic (methotrexate (MTX)+ sulfasalazine+60 mg prednisone tapered to 7.5 mg daily from W7), COBRA Slim (MTX+30 mg prednisone tapered to 5 mg from W6) and COBRA Avant-Garde (MTX+leflunomide+30 mg prednisone tapered to 5 mg from W6). Treatment modifications to target low-disease activity were mandatory from W8, if desirable and feasible according to the rheumatologist. The primary outcome was remission (28 joint disease activity score calculated with C-reactive protein <2.6) at W16 (intention-to-treat analysis). Secondary endpoints were good European League Against Rheumatism response, clinically meaningful health assessment questionnaire (HAQ) response and HAQ equal to zero. Adverse events (AEs) were registered. RESULTS: Data from 98 Classic, 98 Slim and 94 Avant-Garde patients were analysed. At W16, remission was reached in 70.4% Classic, 73.6% Slim and 68.1% Avant-Garde patients (p=0.713). Likewise, no significant differences were shown in other secondary endpoints. However, therapy-related AEs were reported in 61.2% of Classic, in 46.9% of Slim and in 69.1% of Avant-Garde patients (p=0.006). CONCLUSIONS: For high-risk eRA, MTX associated with a moderate step-down dose of GCs was as effective in inducing remission at W16 as DMARD combination therapies with moderate or high step-down GC doses and it showed a more favourable short-term safety profile. EUDRACT NUMBER: 2008-007225-39.


Subject(s)
Antirheumatic Agents/therapeutic use , Arthritis, Rheumatoid/drug therapy , Glucocorticoids/therapeutic use , Isoxazoles/therapeutic use , Methotrexate/therapeutic use , Prednisone/therapeutic use , Sulfasalazine/therapeutic use , Adult , Aged , Arthritis, Rheumatoid/diagnosis , Drug Therapy, Combination/methods , Early Medical Intervention , Female , Humans , Induction Chemotherapy/methods , Leflunomide , Male , Middle Aged , Risk Assessment , Severity of Illness Index , Treatment Outcome
12.
Sci Prog ; 97(Pt 2): 195-6, 2014.
Article in English | MEDLINE | ID: mdl-25109003
13.
Scand J Rheumatol ; 43(4): 265-72, 2014.
Article in English | MEDLINE | ID: mdl-24559216

ABSTRACT

OBJECTIVES: Despite the availability and demonstrated effectiveness of intensive combination treatment strategies (ICTS) for early rheumatoid arthritis (RA), a discrepancy seems to exist between theoretical evidence and actual prescription in daily practice. The purpose of this study was to explore and identify the factors influencing the prescription of ICTS. METHOD: This study involved rheumatologists and nurses participating in the Care for Rheumatoid Arthritis (CareRA) trial, a multicentre randomized controlled trial (RCT) comparing different ICTS for early RA with conventional disease-modifying anti-rheumatic drugs (DMARDs) plus step-down glucocorticoids (GCs). A qualitative study was carried out using individual semi-structured interviews. Each interview was recorded, transcribed literally, and analysed thematically. In addition, observations at outpatient clinics were used to clarify the interpretation of the results. RESULTS: We interviewed 26 rheumatologists and six nurses and observed five outpatient visits. Identified facilitators included available scientific evidence, personal faith in treatment strategy, staff support, and low treatment costs. Rheumatologists had no doubts about the value of methotrexate (MTX) but some questioned the value of combination strategy, others the effectiveness and/or the dosage of individual compounds. Additional barriers for prescribing ICTS included need for patient education, fear for patients' preconceptions, concerns about applicability to the individual patient, difficulties with breaking routine, interference with organizational structures and processes, time constraints, and lack of financial support. CONCLUSIONS: A heterogeneous set of factors highlights the complexity of prescribing ICTS for early RA in daily clinical practice. Future improvement strategies should stimulate the facilitators while at the same time addressing the barriers. The generalizability of these findings to other health care systems needs further examination.


Subject(s)
Antirheumatic Agents/therapeutic use , Arthritis, Rheumatoid/drug therapy , Health Knowledge, Attitudes, Practice , Practice Patterns, Physicians'/statistics & numerical data , Adult , Aged , Drug Therapy, Combination , Female , Health Personnel , Humans , Male , Middle Aged , Treatment Outcome
14.
Clin Rheumatol ; 33(1): 125-30, 2014 Jan.
Article in English | MEDLINE | ID: mdl-24077951

ABSTRACT

The objective of the study was to evaluate the effect of initial disease-modifying antirheumatic drug (DMARD) combination therapy with steroids (ICTS) and DMARD monotherapy (IMT) on the clinical and radiologic evolution of patients with early rheumatoid arthritis (RA) over a 2-year treatment period, applying tight control (TC) in daily practice. Seventy-four DMARD-naive early RA patients received ICTS or IMT in a TC setting. Baseline and year 1 and year 2 X-rays of hands and feet were scored according to Sharp/van der Heijde. Rapid radiographic progression (RRP) was defined as total Sharp score (TSS) of >5 units/year. At year 1, both treatment groups achieved 50 % remission. At year 2, 37 % of IMT and 60 % of ICTS patients were in remission, despite ICTS patients having initially a more severe RA profile. RRP was found in 4/74 patients at year 1: 3 IMT and 1 ICTS patients. Remarkably, three of these four patients had no radiographic progression in the second year. Five other patients had RRP in the second year: four IMT and one ICTS patients. In a TC setting, ICTS and IMT can prevent radiographic progression in the majority of patients in the daily practice of a Belgian academic hospital over 2 years. ICTS seems to be more effective than IMT in achieving higher remission rates and less radiographic progression.


Subject(s)
Antirheumatic Agents/administration & dosage , Arthritis, Rheumatoid/diagnostic imaging , Arthritis, Rheumatoid/drug therapy , Glucocorticoids/administration & dosage , Steroids/administration & dosage , Aged , Cohort Studies , Disease Progression , Female , Follow-Up Studies , Foot/diagnostic imaging , Hand/diagnostic imaging , Humans , Male , Middle Aged , Radiography , Remission Induction , Severity of Illness Index , Surveys and Questionnaires , Time Factors , Treatment Outcome , X-Rays
15.
Semin Arthritis Rheum ; 43(5): 627-31, 2014 Apr.
Article in English | MEDLINE | ID: mdl-24200124

ABSTRACT

OBJECTIVE: To compare in daily clinical practice the reliability of matrices that forecast rapid radiologic progression (RRP) at year one, at year two, and over 2 years in patients with early rheumatoid arthritis (RA). METHODS: Overall, 74 early RA patients with X-rays of hands and feet at baseline, year one, and year two were included. Initial DMARD combination therapy with steroids (ICTS) or DMARD monotherapy (IMT) was initiated according to patients' RA severity, based on rheumatologist opinion. The images were scored via the modified Sharp/van der Heijde (SvH) method. A total Sharp score progression of equal or higher than five per year was considered RRP. Six matrices were tested: ASPIRE CRP/ESR matrices, the BEST matrix, two SWEFOT matrices, and the ESPOIR matrix. Patients were placed in each of them yielding a RRP probability. The performance was tested by Area Under the Curve analysis reflecting the predictive value. RESULTS: Four patients developed RRP in year one, five in year two, and four over 2 years. With regard to face validity, the predicted probability did not correspond to the risk in reality: the one ICTS patient who developed RRP over 2 years was always found in the lowest RRP categories of all matrices. The ASPIRE CRP matrix yielded at least a moderate predicting value for the three time points. The other matrices showed moderate to no predicting value. CONCLUSION: The performance of all matrices was disappointing and it is impossible to fully rely on the existing matrices in daily clinical practice.


Subject(s)
Arthritis, Rheumatoid/diagnostic imaging , Disease Progression , Foot Joints/diagnostic imaging , Hand Joints/diagnostic imaging , Adult , Aged , Humans , Male , Middle Aged , Radiography , Reproducibility of Results , Severity of Illness Index
16.
Scand J Rheumatol ; 43(1): 1-8, 2014.
Article in English | MEDLINE | ID: mdl-24050519

ABSTRACT

OBJECTIVES: A treatment delay of more than 12 weeks can negatively affect treatment response in rheumatoid arthritis (RA). Our aim was to quantify the different stages of delay before RA treatment in different rheumatology centres and to explore influencing factors. METHOD: A total of 156 disease-modifying anti-rheumatic drug (DMARD)-naive early RA patients were included from eight practices: one academic hospital, five general hospitals, and two private practices. Eight different types of delay were defined from symptom onset until treatment initiation. Information on the duration of each stage of delay was collected from the patient, their general practitioner (GP), and patient files at the rheumatology practice. Patient/GP demographics and disease activity/severity parameters were recorded. RESULTS: The median total delay from symptom onset until treatment initiation was 23 weeks whereas patient-, GP- and rheumatologist-related median delay was 10, 4, and 7 weeks, respectively. Only 21.6% of the patients had a total delay of less than 12 weeks. The total median delay in private rheumatology practices was less than in academic and general hospitals (p < 0.001). Furthermore, RA patients treated within 12 weeks of symptom onset showed a higher level of disease activity. The duration of rheumatologist-related delay was inversely correlated with disease activity parameters. Patients with morning stiffness were treated, on average, 3 weeks sooner than those without morning stiffness (p < 0.006). CONCLUSIONS: In only one out of five early RA patients was treatment initiated within 12 weeks of symptom onset, as recommended. Patient-related delay contributed most to overall delay. Disease activity and type of rheumatology centre are pivotal determinants of delay.


Subject(s)
Antirheumatic Agents/therapeutic use , Arthritis, Rheumatoid/drug therapy , Adult , Aged , Arthritis, Rheumatoid/diagnosis , Female , Humans , Male , Middle Aged , Referral and Consultation , Rheumatology , Time Factors , Treatment Outcome
17.
Parasitology ; 141(2): 227-40, 2014 Feb.
Article in English | MEDLINE | ID: mdl-24128728

ABSTRACT

The paramyxean parasite Marteilia refringens infects several bivalve species including European flat oysters Ostrea edulis and Mediterranean mussels Mytilus galloprovincialis. Sequence polymorphism allowed definition of three parasite types 'M', 'O' and 'C' preferably detected in oysters, mussels and cockles respectively. Transmission of the infection from infected bivalves to copepods Paracartia grani could be experimentally achieved but assays from copepods to bivalves failed. In order to contribute to the elucidation of the M. refringens life cycle, the dynamics of the infection was investigated in O. edulis, M. galloprovincialis and zooplankton over one year in Diana lagoon, Corsica (France). Flat oysters appeared non-infected while mussels were infected part of the year, showing highest prevalence in summertime. The parasite was detected by PCR in zooplankton particularly after the peak of prevalence in mussels. Several zooplanktonic groups including copepods, Cladocera, Appendicularia, Chaetognatha and Polychaeta appeared PCR positive. However, only the copepod species Paracartia latisetosa showed positive signal by in situ hybridization. Small parasite cells were observed in gonadal tissues of female copepods demonstrating for the first time that a copepod species other than P. grani can be infected with M. refringens. Molecular characterization of the parasite infecting mussels and zooplankton allowed the distinguishing of three Marteilia types in the lagoon.


Subject(s)
Cercozoa/growth & development , Copepoda/parasitology , Life Cycle Stages , Mytilus/parasitology , Ostrea/parasitology , Zooplankton/parasitology , Animals , Base Sequence , Cercozoa/classification , Cercozoa/genetics , Cercozoa/physiology , Female , France , Gastrointestinal Tract/parasitology , Gonads/parasitology , Histocytochemistry , Host-Parasite Interactions , In Situ Hybridization , Molecular Sequence Data , Polymerase Chain Reaction , Polymorphism, Restriction Fragment Length , Salinity , Sequence Alignment , Sequence Analysis, DNA , Temperature
18.
Parasitology ; 139(13): 1757-71, 2012 Nov.
Article in English | MEDLINE | ID: mdl-22894895

ABSTRACT

Although clam populations in France are known to be infected with protozoans of the genus Perkinsus, no molecular characterization was previously performed on these parasites. Considering that several members of this genus have been associated with mortalities of molluscs worldwide, a study was undertaken in order to characterize these parasites in France. For that purpose, clams, Ruditapes philippinarum and R. decussatus, collected from different production areas and found to be infected with Perkinsus sp. in thioglycolate culture medium, were selected for PCR-RFLP tests and sequencing. Perkinsus olseni was detected in all the investigated areas and results also suggested the presence of P. chesapeaki in Leucate, a lagoon on the Mediterranean coast and in Bonne Anse in Charente Maritime, on the Atlantic coast. Clonal cultures from both detected species were produced in order to describe and compare in vitro stages. Differences in size between both Perkinsus spp. were noticed especially for schizonts and zoosporangia. Lastly, in situ hybridization tests allowed confirmation of the presence of both species in the same R. decussatus population and even in same clams. This is the first detection of P. chesapeaki in Ruditapes species and outside North America, which questions its introduction into Europe.


Subject(s)
Alveolata/physiology , Aquaculture , Bivalvia/parasitology , Alveolata/classification , Alveolata/cytology , Alveolata/genetics , Animals , DNA, Ribosomal Spacer/genetics , France , Genetic Variation , In Situ Hybridization , Molecular Sequence Data , Phylogeny , Species Specificity
19.
Rev Mal Respir ; 29(1): 70-3, 2012 Jan.
Article in French | MEDLINE | ID: mdl-22240223

ABSTRACT

INTRODUCTION: Scwhannomas are uncommon neurogenic tumors of the mediastinum. Most of them are located in the posterior mediastinum usually in the paralateral gutters. We report the case of an uncommon localisation of such a tumour appended to the right vagus nerve in the middle mediastinum. CASE REPORT: The patient was 50 years old and complained of thoracic pain, shortness of breath and dysphagia. CT scanning of thorax and abdomen revealed a heterogeneous mass in the middle mediastinum, which was not visible on plain radiography. Further investigation included transoesophageal ultrasound and PET scan. The diagnosis was confirmed by histopathology after mini video-assisted thoracotomy. The schwannoma was entirely removed without any post-surgical complications. CONCLUSION: We report a novel case of schwannoma arising from the vagus nerve and review the diagnostic strategies. PET scanning has poor sensitivity and specificity and does not therefore contribute to confirm the diagnosis which depends on exploring the mediastimun surgically.


Subject(s)
Cranial Nerve Neoplasms/diagnosis , Cranial Nerve Neoplasms/therapy , Neurilemmoma/diagnosis , Neurilemmoma/therapy , Vagus Nerve Diseases/diagnosis , Vagus Nerve Diseases/therapy , Vagus Nerve , Cranial Nerve Neoplasms/pathology , Diagnostic Techniques, Surgical , Humans , Incidental Findings , Male , Middle Aged , Neurilemmoma/pathology , Pancreatitis, Chronic/diagnosis , Pancreatitis, Chronic/diagnostic imaging , Pancreatitis, Chronic/surgery , Radiography, Thoracic , Vagus Nerve/pathology , Vagus Nerve Diseases/pathology
20.
Gastroenterol Clin Biol ; 34(4-5): 305-9, 2010.
Article in English | MEDLINE | ID: mdl-20627637

ABSTRACT

We report a series of ten cases of the clinical, endoscopic and pathological features of gastric metastases. Patients were six women and four men between 54 and 88 years old, with gastric metastases from breast carcinoma (4), lung carcinoma (4) and melanoma (2). Patients underwent an upper gastrointestinal endoscopy for epigastralgia (2), hematemesis (2), dysphagia (1) and anemia (5). On endoscopy, tumors appeared as nodules with a central ulceration (5), an ulceration (4) or simulating linitis plastica (1). Metastases were located in the cardia (2), fundus (5) and antrum (3). Primary tumors had been diagnosed between one day and 20 years before upper endoscopy. Eight patients had multivisceral metastases. The microscopic features of the gastric metastases resembled a primary gastric cancer in eight cases. Thanks to clinical data, the pathologist confirmed the diagnosis of gastric metastases on immunohistochemistry. Nine patients died in the eight-month follow-up period. Gastric metastases are rare, occur at a late stage of the neoplastic disease, and have a poor prognosis. Diagnosis of gastric metastases is difficult because they simulate primary gastric cancer on endoscopy and on microscopic examination. A correct diagnosis is based on good communication between gastroenterologists and pathologists.


Subject(s)
Endoscopy, Gastrointestinal , Stomach Neoplasms/pathology , Stomach Neoplasms/secondary , Adenocarcinoma/pathology , Adenocarcinoma/secondary , Aged , Aged, 80 and over , Carcinoma, Lobular/pathology , Carcinoma, Lobular/secondary , Female , Humans , Male , Middle Aged , Tomography, X-Ray Computed
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