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121.
Sanfilippo syndrome, or mucopolysaccharidosis type III (MPSIII) is a lysosomal storage disease with predominant neurological manifestations in affected children. It is considered heterogeneous with respect to prevalence, clinical presentation, biochemistry (four biochemical forms of the disease referred to as MPSIIIA, B, C, and D are known), and causative mutations. The perspective of therapeutic options emphasizes the need for better knowledge of MPSIII incidence and natural history. We performed parallel retrospective epidemiological studies of patients diagnosed with MSPIII in France (n = 128), UK (n = 126), and Greece (n = 20) from 1990 to 2006. Incidences ranged from 0.68 per 100,000 live‐births in France to 1.21 per 100,000 live‐births in UK. MPSIIIA, which predominates in France and UK, was absent in Greece, where most patients have MPSIIIB. The study confirmed the large allelic heterogeneity of MPSIIIA and MPSIIIB and detected several yet undescribed mutations. Analysis of clinical manifestations at diagnosis and over a 6–7 years follow‐up indicated that almost all patients, whatever the disease subtype, expressed neurological manifestations before the age of 5 years, including language acquisition delay, cognitive delay, and/or abnormal behavior. In contrast to relatively homogeneous early onset manifestations, disease progression showed significant variation depending on subtype and age at diagnosis. Different severities of disease progressions and different allele distribution between France and UK suggested that mutations are not equally deleterious, although genotype–phenotype correlation could not be established. Notwithstanding the rapidity of further clinical deterioration, all MPSIII patients suffer early onset devastating neurological manifestations that deserve early treatment when available. © 2010 Wiley‐Liss, Inc.  相似文献   
122.
Evidence about the long-term persistence of the booster-mediated immunity against Omicron is mandatory for pandemic management and deployment of vaccination strategies. A total of 155 healthcare professionals (104 COVID-19 naive and 51 with a history of SARS-CoV-2 infection) received a homologous BNT162b2 booster. Binding antibodies against the spike protein and neutralizing antibodies against Omicron were measured at several time points before and up to 6 months after the booster. Geometric mean titers of measured antibodies were correlated to vaccine efficacy (VE) against symptomatic disease. Compared to the highest response, a significant 10.2- and 11.5-fold decrease in neutralizing titers was observed after 6 months in participants with and without history of SARS-CoV-2 infection. A corresponding 2.5- and 2.9-fold decrease in binding antibodies was observed. The estimated T1/2 of neutralizing antibodies in participants with and without history of SARS-CoV-2 infection was 42 (95% confidence interval [CI]: 25–137) and 36 days (95% CI: 25–65). Estimated T1/2 were longer for binding antibodies: 168 (95% CI: 116–303) and 139 days (95% CI: 113–180), respectively. Both binding and neutralizing antibodies were strongly correlated to VE (r = 0.83 and 0.89). However, binding and neutralizing antibodies were modestly correlated, and a high proportion of subjects (36.7%) with high binding antibody titers (i.e., >8434 BAU/ml) did not have neutralizing activity. A considerable decay of the humoral response was observed 6 months after the booster, and was strongly correlated with VE. Our study also shows that commercial assays available in clinical laboratories might require adaptation to better predict neutralization in the Omicron era.  相似文献   
123.
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   
124.
These experiments examine the influence of context manipulations on radial maze performance in C57BL/6 (C57) and DBA/2 (DBA) mice. Animals from each strain were trained in two distinct contexts—poor cuing vs rich cuing—that were sucessively switched. The results first show that C57 performed better when trained under rich cuing conditions than under poor ones, whereas DBA performed poorly under both conditions. In addition, contextual manipulations were found to produce more drastic effects in C57 than in DBA mice. That is, C57 showed a strong performance decrement following each context shift, whereas DBA mice did not. In particular, the fact that DBA mice performed similarly under rich and poor cuing conditions and also reacted mildly—or did not react—to context shifts suggests a deficit in processing contextual information, which places important constraints on their capability to form spatial representations.  相似文献   
125.
Links between human T-cell leukemia virus type 1 and adult T-cell leukemia (ATL) were first suspected in 1980. Provirus integration has since been found in all ATL cells. Although the viral Tax protein is involved in the proliferation of the infected cells during the preleukemic stage, Tax expression is not systematically detected in primary leukemic cells. Recent studies found that the viral HBZ gene was always expressed in leukemic cells, suggesting its involvement in the progression of the infected cells toward malignancy. How could this new discovery be translated into possible new avenues for the prevention or treatment of ATL?  相似文献   
126.
The Th1/Th2 balance deregulation toward a Th2 immune response plays a central role in allergy. We previously demonstrated that administration of recombinant Lactococcus lactis strains expressing bovine beta-lactoglobulin (BLG), a major cow's milk allergen, partially prevents mice from sensitization. In the present study, we aimed to improve this preventive effect by coadministration of L. lactis BLG and a second recombinant L. lactis strain producing biologically active interleukin-12 (IL-12). This L. lactis strain producing IL-12 was previously used to enhance the Th1 immune response in a tumoral murine model (L. G. Bermúdez-Humarán et al., J. Immunol. 175:7297-7302, 2005). A comparison of the administration of either BLG alone or BLG in the presence of IL-12 was conducted. A BLG-specific primary Th1 immune response was observed only after intranasal coadministration of both L. lactis BLG and IL-12-producing L. lactis, as demonstrated by the induction of serum-specific immunoglobulin G2a (IgG2a) concomitant with gamma interferon secretion by splenocytes, confirming the adjuvanticity of IL-12-producing L. lactis. Immunized mice were further sensitized by intraperitoneal administration of purified BLG, and the allergic reaction was elicited by intranasal challenge with purified BLG. Mice pretreated with BLG in either the presence or the absence of IL-12 were rendered completely tolerant to further allergic sensitization and elicitation. Pretreatment with either L. lactis BLG or L. lactis BLG and IL-12-producing L. lactis induces specific anti-BLG IgG2a production in serum and bronchoalveolar lavage (BAL) fluid. Although specific serum IgE was not affected by these pretreatments, the levels of eosinophilia and IL-5 secretion in BAL fluid were significantly reduced after BLG challenge in the groups pretreated with L. lactis BLG and L. lactis BLG-IL-12-producing L. lactis, demonstrating a decreased allergic reaction. Our data demonstrate for the first time (i) the induction of a protective Th1 response by the association of L. lactis BLG and IL-12-producing L. lactis which inhibits the elicitation of the allergic reaction to BLG in mice and (ii) the efficiency of intranasal administration of BLG for the induction of tolerance.  相似文献   
127.
To determine diagnostic cytomorphologic features of osteosarcoma on fine-needle aspiration materials, we reviewed the cytologic material and corresponding histologic slides of 126 tumors in 107 patients. Fifty-five (43.6%) tumors were primary, 31 (24.6%) were recurrent, and 40 (31.8%) were metastatic. Review of original cytology reports revealed that 120 (95.3%) tumors were diagnosed as malignant. Six (4.7%) cases were reported as suspicious, false-negative, or unsatisfactory samples.Our findings showed that osteoblastic roundish cells, spindle-shaped cells, reactive giant cells, and osteoid were the most consistent features representative of osteosarcoma. Periosteal reactions, fractures with callous formation, giant cells of osteoclastic type in various conditions, chondrosarcoma with enchondral ossification are entities to consider in the differential diagnosis.  相似文献   
128.
The influence of cellulose ether additives (CEAs) on the performance of final calcium phosphate cement (CPC) products is thoroughly investigated. Four CEAs were added into the liquid phase of apatitic CPCs based on the hydrolysis of α-tricalcium phosphate, to investigate the influence of both molecular weight and degree of substitution on the CPCs’ properties, including handling (e.g. injectability, cohesion, washout resistance and setting time), microstructure (e.g. porosity and micromorphology) and mechanical properties (e.g. fracture toughness and compressive strength). The results showed that even a small amount of CEAs modified most of these CPCs’ features, depending on the structural parameters of the CEAs. The CEAs dramatically improved the injectability, cohesion and washout resistance of the pastes, prolonged the final setting time and increased the porosity of CPCs. Moreover, the CEAs had an evident toughening effect on CPCs, and this effect become more significant with increasing molecular weight and mass fraction of CEAs, inducing a significant tolerance to damage. Overall, the molecular weight of CEAs played a major role compared to their degree of substitution in CPCs’ performances.  相似文献   
129.
Levels of educational and occupational attainment, as components of cognitive reserve, may modify the relationship between the pathological hallmarks and cognition in Alzheimer's disease (AD). We examined whether exposure of a Tg2576 transgenic mouse model of AD to environmental enrichment (EE) at a specific period during the amyloidogenic process favored the establishment of a cognitive reserve. We found that exposure to EE during early adulthood of Tg2576 mice—before amyloidogenesis has started—reduced the severity of AD-related cognitive deficits more efficiently than exposure later in life, when the pathology is already present. Interestingly, early-life exposure to EE, while slightly reducing forebrain surface covered by amyloid plaques, did not significantly impact aberrant inhibitory remodeling in the hippocampus of Tg2576 mice. Thus, transient early-life exposure to EE exerts long-lasting protection against cognitive impairment during AD pathology. In addition, these data define the existence of a specific life time frame during which stimulatory activity most efficiently builds a cognitive reserve, limiting AD progression and favoring successful aging.  相似文献   
130.
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