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71.
The recombination events of the γ and β T-cell receptor (TCR) loci were analysed in a series of 39 peripheral T-cell lymphomas (PTCLs) in association with the expression of TCR chains. In TCR αβ PTCLs, 22/23 cases showed a γ-gene rearrangement while only 18/23 showed a concomitant β-gene rearrangement. The germline configuration of the β locus was found in angioimmunoblastic lymphadenopathy and lymphoepithelioid lymphomas. Three γδ PTCLs rearranged both γ and β genes. TCR silent PTCLs showed three different patterns of γ- and β-gene rearrangements. Three cases were in germline configuration for both loci; five cases had a rearranged γ and a germline β locus; and five cases had the two loci rearranged. Regarding the variable genes in the γ-rearranged alleles, members of the VγI subgroup were the most frequently presented (39/50), followed by VγII, VγIII, and VγIV (9/50, 1/50, and 1/50, respectively). Joining segment usage was as follows: J1 or J2 (32/50), JP1 or JP2 (17/50), and JP (1/50). Taken together, these data demonstrate that the γ locus is more frequently rearranged whatever the TCR expression. The γ-locus analysis provides a better diagnostic yield than the β locus in the study of PTCL clonality.  相似文献   
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We have tested the involvement of the invariant chains (Ii) p31 and p41 in the presentation of peptides derived from hen egg lysozyme (HEL) constructs targeted to different intracellular compartments within transfected fibroblasts. The endogenous HEL constructs were either present in the cytosol (HELc), secreted (HELs), or linked to the mammalian (KDEL C-terminal sequence that causes retention of HEL in the endoplasmic reticulum (ER)/pre-Golgi recycling compartment (HELr). Using Ii-negative antigen-presenting cells, the presentation of HELr to a HEL 46-61 specific T cell hybridoma was far less efficient than the presentation of the HELs. High levels of Ii expression enhanced drastically the presentation of the HEL 46-61 determinant derived from both HELr and HELs. HELr and HELs presentation was fully sensitive to lysosomotropic agents such as chloroquine, indicating that the formation of complexes between major histocompatibility complex (MHC) class II molecules and determinants derived from endogenous antigens entering the secretory pathway is taking place in an acidic compartment. The degradation and dissociation of Ii might be a prerequisite for the efficient presentation of endogenously derived determinants by MHC class II molecules, as for the presentation of most exogenous antigens. All our results are compatible with the notion that endogenous molecules being translocated into the lumen of the ER could be presented by class II molecules through a processing pathway involving an acidic compartment in which Ii chains dissociate from class II molecules.  相似文献   
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We detected 3 genotypes of highly pathogenic avian influenza A(H5N8) virus in France during winter 2016–17. Genotype A viruses caused dramatic economic losses in the domestic duck farm industry in southwestern France. Our phylogenetic analysis suggests that genotype A viruses formed 5 distinct geographic clusters in southwestern France. In some clusters, local secondary transmission might have been started by a single introduction. The intensity of the viral spread seems to correspond to the density of duck holdings in each production area. To avoid the introduction of disease into an unaffected area, it is crucial that authorities limit the movements of potentially infected birds.  相似文献   
76.
Cell-free DNA (Cf-DNA) fragments may constitute an easy-to-measure molecular tool for guiding the choice of care provided to infertile couples who benefit assisted reproductive technology (ART) programmes. Data on Cf-DNA levels in the seminal plasma of men with sperm alterations are scarce. The objective of the present study was to quantify the presence of Cf-DNA in semen by using a quantitative real-time PCR. We compared men with abnormal sperm characteristics (n = 21) with normospermic controls (n = 21). The PCR assay evidenced significantly higher mean Cf-DNA levels in patients with sperm abnormalities than in controls (2.09 versus 1.18 µg/ml, respectively; p = .0003). The Cf-DNA levels were notably higher in men with azoospermia (3.65 µg/ml, versus 1.34 µg/ml in matched controls; p = .03) and men with teratozoospermia (1.80 µg/ml, versus 1.29 µg/ml in matched controls; p = .008). Our data report a significant association between elevated Cf-DNA levels and sperm abnormalities. These results may open up new diagnostic and prognostic perspectives in male infertility.  相似文献   
77.
BackgroundOwing to improved quality of computed tomography, a new category of complicated acute diverticulitis, including patients with pericolic air but without abscess formation, can be defined (Hinchey 1a). Recent studies question whether this new category of acute diverticulitis could be treated as uncomplicated cases. The aim of our study is to report on the clinical course of acute diverticulitis Hinchey 1a in current clinical practice.MethodsFor this multicenter retrospective cohort study, patients presenting at the emergency department with Hinchey 1a acute diverticulitis as demonstrated by computed tomography scan, were identified. The primary outcome measure was successful conservative treatment with observation alone, antibiotics, and/or hospital admission. Readmissions, percutaneous drainage of abscesses, and emergency operations were considered as failure.ResultsBetween October 2016 and October 2018, 1,199 patients were clinically suspected for acute diverticulitis, of whom 101 (8.4%) were radiologically diagnosed to have type 1a acute diverticulitis (average age 57 (±13) years, 45% female) and started with conservative treatment. This was successful in 86 (85%) patients. One of the 15 unsuccessfully treated patients (1%) received percutaneous drainage of an abdominal abscess. Surgery was required in 9 cases (9%) after a median time of 6 days (range, 3 to 69 days). Although a difference in the volume of extraluminal air on computed tomography scan was found, this was not shown to be a risk factor for the clinical course.ConclusionPatients with type 1a acute diverticulitis can be treated successfully by conservative therapy in the majority of cases (85%). More research is required to define predictive factors for successful conservative management.  相似文献   
78.
It is unknown if solid organ transplant recipients are at higher risk for severe COVID-19. The management of a lung transplantation (LTx) program and the therapeutic strategies to adapt the immunosuppressive regimen and antiviral measures is a major issue in the COVID-19 era, but little is known about worldwide practice. We sent out to 180 LTx centers worldwide in June 2020 a survey with 63 questions, both regarding the management of a LTx program in the COVID-19 era and the therapeutic strategies to treat COVID-19 LTx recipients. We received a total of 78 responses from 15 countries. Among participants, 81% declared a reduction of the activity and 47% restricted LTx for urgent cases only. Sixteen centers observed deaths on waiting listed patients and eight centers performed LTx for COVID-19 disease. In 62% of the centers, COVID-19 was diagnosed in LTx recipients, most of them not severe cases. The most common immunosuppressive management included a decreased dose or pausing of the cell cycle inhibitors. Remdesivir, hydroxychloroquine, and azithromycin were the most proposed antiviral strategies. Most of the centers have been affected by the COVID-19 pandemic and proposed an active therapeutic strategy to treat LTx recipients with COVID-19.  相似文献   
79.
Clémence Jacquin  Emilie Landais  Céline Poirsier  Alexandra Afenjar  Ahmad Akhavi  Nathalie Bednarek  Caroline Bénech  Adeline Bonnard  Damien Bosquet  Lydie Burglen  Patrick Callier  Sandra Chantot-Bastaraud  Christine Coubes  Charles Coutton  Bruno Delobel  Margaux Descharmes  Jean-Michel Dupont  Vincent Gatinois  Nicolas Gruchy  Sarah Guterman  Abdelkader Heddar  Lucas Herissant  Delphine Heron  Bertrand Isidor  Pauline Jaeger  Guillaume Jouret  Boris Keren  Paul Kuentz  Cedric Le Caignec  Jonathan Levy  Nathalie Lopez  Zoe Manssens  Dominique Martin-Coignard  Isabelle Marey  Cyril Mignot  Chantal Missirian  Céline Pebrel-Richard  Lucile Pinson  Jacques Puechberty  Sylvia Redon  Damien Sanlaville  Marta Spodenkiewicz  Anne-Claude Tabet  Alain Verloes  Gaelle Vieville  Catherine Yardin  François Vialard  Martine Doco-Fenzy 《American journal of medical genetics. Part A》2023,191(2):445-458
Chromosome 1p36 deletion syndrome (1p36DS) is one of the most common terminal deletion syndromes (incidence between 1/5000 and 1/10,000 live births in the American population), due to a heterozygous deletion of part of the short arm of chromosome 1. The 1p36DS is characterized by typical craniofacial features, developmental delay/intellectual disability, hypotonia, epilepsy, cardiomyopathy/congenital heart defect, brain abnormalities, hearing loss, eyes/vision problem, and short stature. The aim of our study was to (1) evaluate the incidence of the 1p36DS in the French population compared to 22q11.2 deletion syndrome and trisomy 21; (2) review the postnatal phenotype related to microarray data, compared to previously publish prenatal data. Thanks to a collaboration with the ACLF (Association des Cytogénéticiens de Langue Française), we have collected data of 86 patients constituting, to the best of our knowledge, the second-largest cohort of 1p36DS patients in the literature. We estimated an average of at least 10 cases per year in France. 1p36DS seems to be much less frequent than 22q11.2 deletion syndrome and trisomy 21. Patients presented mainly dysmorphism, microcephaly, developmental delay/intellectual disability, hypotonia, epilepsy, brain malformations, behavioral disorders, cardiomyopathy, or cardiovascular malformations and, pre and/or postnatal growth retardation. Cardiac abnormalities, brain malformations, and epilepsy were more frequent in distal deletions, whereas microcephaly was more common in proximal deletions. Mapping and genotype–phenotype correlation allowed us to identify four critical regions responsible for intellectual disability. This study highlights some phenotypic variability, according to the deletion position, and helps to refine the phenotype of 1p36DS, allowing improved management and follow-up of patients.  相似文献   
80.
The objectives of this study were: i) to analyse the effects of morphine and naloxone on the rat's behaviour in the hot plate test using an ethological approach, and ii) to compare the effectiveness of repeated versus single test paradigms. Animals received either morphine (0, 3, 6 or 9 mg/kg SC) or naloxone (0, 0.01, 0.1 or 1 mg/kg SC). For repeated hot plate measures, rats were tested before and 60, 120, 180 and 240 min following morphine treatment, as well as 30, 60, 90 and 120 min after naloxone injection. For the single test schedule, rats were tested only once 60 min after morphine or 30 min after naloxone administration, or at 60, 120, 180, 240 and 300 min after 9 mg/kg morphine treatment. Behaviour was videotaped and analysed by an ethogram and ethological techniques. A cluster analysis revealed that the most frequently displayed patterns could be categorised into exploratory sniffing reactions (walk-sniff, immobile-sniff) and noxious-evoked elements, including primary (paw-licking, stamping), escape (jumping, leaning posture) and independent (hindleg-withdrawal) patterns. During repeated tests, morphine treatment induced: i) a maximum hypoalgesic effect 60 min post-injection (noxious-evoked patterns were significantly reduced), and ii) an unexpected thermal hyperreactivity rebound effect after 120 min (paw-licking and hindleg-withdrawal were enhanced), although changes in hindpaw-licking are more indicative of a hyperalgesic rebound effect. Most changes were quite similar during the single test schedule at 60 and 120 min after morphine injection. With regard to naloxone treatment, jumping latency was significantly decreased during the repeated test schedule, but not on single exposure to the plate. Other elements were facilitated, however, in the single test (stamping, leaning posture, hindleg-withdrawal). The results indicated that both repeated and single tests paradigms are of value for testing the effects of morphine and naloxone on rats. However, under our conditions the single test paradigm gave a better picture of the overall effects of the drug. Learning as well as habituation and sensitization may mask certain effects during repeated tests. In conclusion, an ethological analysis of the rat's behaviour in the hot plate test following administration of morphine and naloxone has been validated in this study.  相似文献   
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