The spread of the wild Poliovirus in the rural environment, the case of the Adzopé health district, Côte d'Ivoire

Wild Poliovirus spreading in rural environment in Adzopé, C?te d'Ivoire In order to determine the level of wild Poliovirus spreading among rural children in an endemic poliomyelitis country 469 stools samples, from children aged between three weeks and twelve years old were processed according to WHO procedures for transportation, conservation, isolation and identification of Poliovirus. Intratypic differenciation was performed by an antigenic method using monoclonal antibodies and a genomic RFLP (Restriction Fragment Length Polymorphism). 50 Poliovirus strains (10.7%) were isolated and analyzed: 15 vaccine-like Poliovirus type 1 (30%), 30 vaccine-like Poliovirus type 2 (60%), 4 vaccine-like Poliovirus type 3 (8%) and one wild Poliovirus type 3 (2%). As expected, in the major cases the duration of post-vaccinal viral excretion did not exceed two months. However, in 14% of cases, it varied between 3 and 9 months after the third OPV dose. This long excretion could be due to an inefficient local intestinal immunity or no local immunity at all, in spite of the three OPV doses. These results argue in favor of an increase of the number of OPV doses in such endemic zones. Moreover, OPV strains are well-known to revert to pathogenicity in vaccinees, therefore, the long term excretion of pathogenic OPV derived strains by a certain amount of vaccinees needs to be considered quite seriously.     

Complete or partial seroreversion in immunocompetent individuals after self-limited HCV infection: consequences for transfusion

BACKGROUND: The disappearance of anti-HCV antibodies over time, after a self-limited infection, also referenced seroreversion, has been observed. The frequency of this phenomenon remains controversial, especially in immunocompetent subjects. However, it has important implications in the context of transfusion inquiries, in particular in case of a blood donor suspected to have transmitted HCV through a past blood donation. STUDY DESIGN AND METHODS: Our findings are presented of a longitudinal study, including 16 patients from a cohort of 78 immunocompetent, multitransfused individuals who were positive for anti-HCV (EIA and confirmatory assay [RIBA]) and followed over a long period of time without having received any antiviral therapy. The aim was to establish whether a past and self-resolved HCV infection could evolve toward a negative serology. RESULTS: The 16 patients were classified in three groups: 1) 12 patients who remained anti-HCV positive with no evolution in their RIBA pattern after a mean follow-up of 7.6 years; 2) one patient who presented a complete seroreversion 6 years after enrollment; and 3) three patients with a partial seroreversion over a mean follow-up of 16 years. CONCLUSION: HCV infection is not always characterized by a persistent antibody response, even in immunocompetent individuals. This should be taken into consideration when transfusion inquiries are conducted.     

A method for simulation of foveal vision during wear of corrective lenses.

PURPOSE: The aim was to simulate the visual appearance of images viewed through corrective lenses having known, arbitrary types and amounts of monochromatic aberration, so that the visual effect of changing the design parameters of the lens could be explored. METHODS: We first calculate the optical response of the eye and any corrective lens using a numerical model eye. We then use this response as a filter, which we convolve with a selected original (unaberrated) image, to obtain an initial simulated retinal image. This image is then deconvolved by a second filter, which is calculated as the optical response of the eye of the observer who views the final image displayed on a video monitor. The originality of our approach to visual simulation is to take the aberrational characteristics of the observer's eye into account in the calculation. We validated our simulation by comparing images degraded by simulated dioptric blur with real defocused images seen through corresponding optical lenses. RESULTS: When using a small (2.5 mm) pupil size and a "typical" observer wavefront aberration model, there was a close resemblance between optical and simulated blurs. Although it was not necessary to consider the measured aberrations of the subject when simulating vision with a small pupil size, this requirement could not be ignored when vision through a larger pupil was simulated. With a 5.7-mm pupil diameter, use of Shack-Hartmann measurements of the ocular aberrations of the individual observers rather than "typical" levels of aberrations for the entire population gave excellent agreement between the effects of simulated and real defocus blur in monochromatic and polychromatic light. A Bland-Altman analysis of the differences between matching simulated and real blurs for a 5.7-mm pupil in polychromatic light with the model including allowance for individual measured aberrations gave mean differences close to zero and 95% confidence limits of about +/-0.25 D over a defocus range of -2.00 to +2.00 D. CONCLUSION: The simulation technique can be expected to be a useful tool to evaluate the potential performance of an eye that wears various designs of corrective lens.     

On the stability of insulin delivered through a new glucose-responsive polymeric composite membrane

A new glucose-responsive polymeric composite membrane that provided pulsatile insulin release was developed in our laboratory previously. To develop a clinically useful insulin delivery system, this study was designed to investigate factors influencing insulin stability during delivery by this membrane. The effects of stirring, release duration, insulin concentration and surfactant on insulin stability were studied under both incubation and delivery conditions in a buffer solution at 37 degrees C. The structural change of insulin was characterized by reverse-phase HPLC and circular dichroism. Hydrophobicity of various contact surfaces was determined by contact angle measurement. The results indicated that insulin concentration played an important role in the insulin stability, followed by stirring. Treating the membrane with a non-ionic surfactant prevented insulin denaturation during delivery through the membrane.     

Inhibition of MUC4 expression suppresses pancreatic tumor cell growth and metastasis

The MUC4 mucin is a high molecular weight membrane-bound glycoprotein. It is aberrantly expressed in pancreatic tumors and tumor cell lines with no detectable expression in the normal pancreas. A progressive increase of MUC4 expression has also been observed in pancreatic intraepithelial neoplasia, suggesting its association with disease development. Here, we investigated the consequences of silencing MUC4 expression in an aggressive and highly metastatic pancreatic tumor cell line CD18/HPAF that expresses high levels of MUC4. The expression of MUC4 was down-regulated by the stable integration of a plasmid-construct expressing antisense-MUC4 RNA. A decrease in MUC4 expression, confirmed by Western blot and immunofluorescence analyses, resulted in diminished growth and clonogenic ability of antisense-MUC4-transfected (EIAS19) cells compared with parental, empty vector (ZEO) and sense transfected (ES6) control cells. In addition, EIAS19 cells displayed a significant decrease in tumor growth and metastatic properties when transplanted orthotopically into the immunodeficient mice. In vitro biological assays for motility, adhesion, and aggregation demonstrated a 3-fold decrease in motility of EIAS19 cells compared with control cells, whereas these cells adhered more and showed an increase in cellular aggregation. Interestingly, MUC4 down-regulation also correlated with the reduced expression of its putative interacting partner, HER2/neu, in antisense-MUC4-transfected cells. In conclusion, the present work demonstrates, for the first time, a direct association of the MUC4 mucin with the metastatic pancreatic cancer phenotype and provides experimental evidence for a functional role of MUC4 in altered growth and behavioral properties of the tumor cell.     

Clonidine in acute aversive inner tension and self-injurious behavior in female patients with borderline personality disorder

BACKGROUND: States of strong aversive inner tension and dissociative symptoms are clinical hallmarks of borderline personality disorder and major reasons for self-injurious behavior, a severe clinical condition for which there are no established pharmacologic treatment options. METHOD: The acute effect of 75 and 150 microg of clonidine administered orally in acute states of strong aversive inner tension and urge to commit self-injurious behavior was examined in 14 female patients meeting DSM-IV criteria for borderline personality disorder. Before and 30, 60, and 120 minutes after administration of clonidine, aversive inner tension and dissociative symptoms were assessed using a self-rating instrument for aversive inner tension and dissociation (Dissociation-Tension-Scale acute), and the urge to commit self-injurious behavior and suicidal ideations were assessed using self-rating Likert scales. Blood pressure and heart rate were monitored during the trial. RESULTS: Aversive inner tension and urge to commit self-injurious behavior before administration of clonidine were strong. After administration of clonidine in both doses, aversive inner tension, dissociative symptoms, urge to commit self-injurious behavior, and suicidal ideations significantly decreased. The strongest effects were seen between 30 and 60 minutes after drug intake and correspond to the pharmacokinetics of clonidine with maximum plasma concentrations after 1 hour. Blood pressure and aversive inner tension and dissociative symptoms were positively correlated before and after administration of clonidine. CONCLUSION: Orally given clonidine may be effective for treatment of acute states of aversive inner tension, dissociative symptoms, and urge to commit self-injurious behavior in female patients with borderline personality disorder. Further placebo-controlled studies with larger populations are needed to confirm this finding.     

Perception of dynamic action in patients with schizophrenia

Neuropsychological studies have revealed that schizophrenic (SZ) patients have severe impairments in the cognitive integration of static and moving perceptual stimuli. Research on knowledge structures has shown that sequences of continuous actions are represented in memory as clusters of goal-directed events in a hierarchical manner. In the present study, we investigated the ability to segment familiar sequences of dynamic goal-directed actions into small and large meaningful units in a group of patients with schizophrenia (N = 16) and a group of healthy control subjects (N = 17). While viewing two videotaped movies, participants were requested to detect the transitions between component events at both low and high levels of the action categorical structure. Both groups detected significantly more events under the small-oriented condition as compared to the large-oriented condition. Differently from normal controls, patients recalled the event scenes in a detailed and fragmentary manner and showed considerable difficulties in detecting large action units. Moreover, low performance on action boundary detection significantly correlated with higher levels of disorganisation symptoms in patients with schizophrenia. A defective conceptual organisation of perceptive action knowledge would help to explain the severe everyday difficulties of these patients both in monitoring their own actions and in understanding others' intentions.