Posterior epidural migration of lumbar intervertebral fragment: case report

Disc fragments are well known to migrate to superior, inferior, or lateral sites in the anterior epidural space, posterior epidural migrated lumbar disc fragments is an extremely rare disorder. Posterior epidural migrated lumbar disc fragments are often confused with other posterior epidural space-occupying lesions (cysts, abscesses, tumors, and hematomas). We reported the case of a 52- year-old man presented with progressive not systematizes bilateral radiculopathy complicated one week before admission a difficulty dorsiflexion prevents the start, and the stared to use crutches. Clinical examination revealed steppage gait and a strength score of 3/5 on dorsiflexion of feet. MR imaging of lumbar spine showed right posterolateral epidural mass that compressed the dural sac at the L3-4 level. Patient underwent surgery using posterior approach, an L3 laminectomy was performed, the extruded disk fragment was gently removed and L3-L4 interspace was explored. Histopathology confirmed the (PEMLIF). Postoperative course was uneventful

Analysis of current collapse effect in AlGaN/GaN HEMT: experiments and numerical simulations

In this work, current collapse effects in AlGaN/GaN HEMTs are investigated by means of measurements and two-dimensional physical simulations. According to pulsed measurements, the used devices exhibit a significant gate-lag and a less pronounced drain-lag ascribed to the presence of surface/barrier and buffer traps, respectively. As a matter of fact, two trap levels (0.45 eV and 0.78 eV) were extracted by trapping analysis based on isothermal current transient. On the other hand, 2D physical simulations suggest that the kink effect can be explained by electron trapping into barrier traps and a consequent electron emission after a certain electric-field is reached

Reptilian assemblages from the latest Cretaceous - Palaeogene phosphates of Morocco: from Arambourg to present time.

International audienc

Roles of Capsule and Lipopolysaccharide O Antigen in Interactions of Human Monocyte-Derived Dendritic Cells and Klebsiella pneumoniae▿

In humans, Klebsiella pneumoniae is a saprophytic bacterium of the nasopharyngeal and intestinal mucosae that is also frequently responsible for severe nosocomial infections. Two major factors of virulence, capsular polysaccharide (CPS) and lipopolysaccharide (LPS) O antigen, are involved in mucosal colonization and the development of infections. These bacterial surface structures are likely to play major roles in interactions with the mucosal immune system, which are orchestrated by a network of surveillance based on dendritic cells (DCs). To determine the roles of K. pneumoniae CPS and LPS in the DC response, we investigated the response of immature human monocyte-derived DCs to bacterial challenge with a wild-type strain and its isogenic mutants deficient in CPS or LPS O-antigen production. As observed by flow cytometry and confocal laser microscopy, the rate of phagocytosis was inversely proportional to the amount of CPS on the bacterial cell surface, with LPS playing little or no role. The K. pneumoniae wild-type strain induced DC maturation with upregulation of CD83, CD86, and TLR4 and downregulation of CD14 and DC-SIGN. With CPS mutants, we observed a greater decrease in DC-SIGN, suggesting a superior maturation of DCs. In addition, incubation of DCs with CPS mutants, and to a lesser extent with LPS mutants, resulted in significantly higher Th1 cytokine production. Combined, our findings suggest that K. pneumoniae CPS, by hampering bacterial binding and internalization, induces a defective immunological host response, including maturation of DCs and pro-Th1 cytokine production, whereas the LPS O antigen seems to be involved essentially in DC activation