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81.
82.
The authors report a case of congenital absence of pedicle in the thoracic spine which is uncommon. The lesion may occur at three stages of vertebral development: membranous, cartilaginous or osseous. Careful examination of the X-rays allows visualisation of pedicle aplasia or hypoplasia, associated with controlateral and posterior arch lesions, confirming the congenital origin. Computed tomography scan allows careful analysis of the lesions and eliminates others causes of absence of pedicle, avoiding invasive and expensive explorations.  相似文献   
83.
Clinical and computed tomography (CT) examination of the temporomandibular joint (TMJ) was performed in 26 patients with rheumatoid arthritis (RA) and 26 control subjects. Each examination was scored. In the group with RA 61.2% had physical signs in the stomatognathic system compared to 42.3% in a control group (NS); 88.4% of the group with RA had erosive or cystic lesions of the TMJ compared to 57.6% of control subjects (p less than 0.05). The clinical dysfunction score did not correlate with the CT TMJ score in RA. It correlated with the number of slow acting antirheumatic drugs used, the rheumatoid factor titer and radiographic scores of the hands and cervical spine. In agreement with others, we believe that the only specific CT lesions of RA are erosions and cysts of the mandibular condyle, that there is no correlation between clinical and CT findings of TMJ in RA, and that the intensity of destructive lesions of TMJ on CT in RA is well correlated with the severity of the disease.  相似文献   
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Objective

Ultrasound (US) seems a useful tool for diagnosis of calcium pyrophosphate (CPP) deposition (CPPD). We aimed to compare the performance of US and conventional radiography of the wrist for diagnosis of CPPD.

Methods

Patients with CPP crystals identified in synovial fluid (SF) (knee, hip, shoulder, ankle or wrist) were consecutively included and compared to patients without CPP crystals in synovial fluid considered as controls. As recommended, we used the term chondrocalcinosis (CC) to assess imaging features suggesting CPPD. In all patients, US and radiographic assessment of CC of the wrists was performed by two distinct operators blinded each other (one operator by imaging modality). The two operators were blinded to clinical data, SF analysis and US or radiography findings.

Results

We included 32 CPPD patients and 26 controls. Among CPPD patients, US revealed CC in 30 (93.7%) and radiography in 17 (53.1%) (P < 0.001). The sensitivity and specificity of US for the diagnosis of CPPD were 94% and 85%, respectively; the positive likelihood ratio (LR + ) was 6.1. The sensitivity and specificity of radiography were 53.1% and 100%, respectively. At joints level independently of SF analysis, US revealed CC in 35 joints without radiographic CC whereas X-rays showed CC in 3 joints without US CC. The κ coefficient between US and radiography for CC was moderate: 0.33 (0.171–0.408).

Conclusion

Our study suggests that wrist US should be considered as a relevant tool for the diagnosis of CPPD, with higher sensitivity than radiography for detecting CPP deposits.  相似文献   
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The anti-epileptic drug vigabatrin induces an irreversible constriction of the visual field, but is still widely used to treat infantile spasms and some forms of epilepsy. We recently reported that vigabatrin-induced cone damage is due to a taurine deficiency. However, optic atrophy and thus retinal ganglion cell degeneration was also reported in children treated for infantile spasms. We here show in neonatal rats treated from postnatal days 4 to 29 that the vigabatrin treatment triggers not only cone photoreceptor damage, disorganisation of the photoreceptor layer and gliosis but also retinal ganglion cell loss. Furthermore, we demonstrate in these neonatal rats that taurine supplementation partially prevents these retinal lesions and in particular the retinal ganglion cell loss. These results provide the first evidence of retinal ganglion cell neuroprotection by taurine. They further confirm that taurine supplementation should be administered with the vigabatrin treatment for infantile spasms or epilepsy.  相似文献   
89.
Bioaccumulation enables to integrate the ability of aquatic organisms to regulate metals and effects of water chemistry on metal bioavailability. Linking this process to biological responses offers thus promising lines of enquiry for protecting aquatic ecosystems. This study aims at characterizing the mechanisms involved in waterborne Cu bioaccumulation and assessing metal impact on digestive metabolism in an ecosystem engineer widely distributed in Europe, Gammarus pulex. The organism was exposed to several Cu concentrations (from 0.5 to 100?μg/L) in aquatic microcosms to establish kinetic parameters for the construction and comparison of two bioaccumulation models, i.e. the biodynamic and saturation models. Cu uptake was recorded in waters exhibiting various concentrations of Na, Mg and Ca at environmental levels to assess the influence of cationic composition on bioaccumulation. Then, the effect of increasing Cu in exposure media on the digestive metabolism of G. pulex was investigated by measuring enzymatic activities (β-glucosidase, N-acetyl-β-glucosaminidase, β-galactosidase). We showed that the saturation model is more suitable than the biodynamic model to describe Cu bioaccumulation in gammarids due to a maximal capacity of animals to accumulate the metal. Cationic composition of water affected insignificantly Cu uptake. All activities of tested enzymes decreased with increasing Cu in exposure media but with different degrees. High correlations were established between the inhibition of enzymatic activities and amounts of Cu bioaccumulated by gammarids. These biological responses could thus provide early-warming of Cu impact on aquatic biota.  相似文献   
90.
Despite the increasing impact of rhabdoviruses in European percid farming, the diversity of the viral populations is still poorly investigated. To address this issue, we sequenced the partial nucleoprotein (N) and complete glycoprotein (G) genes of nine rhabdoviruses isolated from perch (Perca fluviatilis) between 1999 and 2010, mostly from France, and analyzed six of them by immunofluorescence antibody test (IFAT). Using two rabbit antisera raised against either the reference perch rhabdovirus (PRhV) isolated in 1980 or the perch isolate R6146, two serogroups were distinguished. Meanwhile, based on partial N and complete G gene analysis, perch rhabdoviruses were divided into four genogroups, A-B-D and E, with a maximum of 32.9% divergence (G gene) between isolates. A comparison of the G amino acid sequences of isolates from the two identified serogroups revealed several variable regions that might account for antigenic differences. Comparative analysis of perch isolates with other rhabdoviruses isolated from black bass, pike-perch and pike showed some strong phylogenetic relationships, suggesting cross-host transmission. Similarly, striking genetic similarities were shown between perch rhabdoviruses and isolates from other European countries and various ecological niches, most likely reflecting the circulation of viruses through fish trade as well as putative transfers from marine to freshwater fish. Phylogenetic relationships of the newly characterized viruses were also determined within the family Rhabdoviridae. The analysis revealed a genetic cluster containing only fish viruses, including all rhabdoviruses from perch, as well as siniperca chuatsi rhabdovirus (SCRV) and eel virus X (EVEX). This cluster was distinct from the one represented by spring viraemia of carp vesiculovirus (SVCV), pike fry rhabdovirus (PFRV) and mammalian vesiculoviruses. The new genetic data provided in the present study shed light on the diversity of rhabdoviruses infecting perch in France and support the hypothesis of circulation of these viruses between other hosts and regions within Europe.  相似文献   
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