Biochemical characterization of three nucleopolyhedrovirus isolates of Spodoptera exigua and Mamestra brassicae

Three nucleopolyhedroviruses (NPVs), of different geographical origins, were biochemically characterized and compared. Two that were isolated from Spodoptera exigua (Se-UZB and Se-SP3) in Uzbekistan and Spain were SeMNPV type, and the third which was isolated from Mamestra brassicae (Mb-PL) in Poland was MbMNPV type. The Spanish isolate Se-SP3 showed restriction endonuclease (REN) profiles that were closely related to two previously described Spanish strains Se-SP1 and Se-SP2, but had some unique and characteristic REN fragments. On the other hand, comparison between the Uzbekian (Se-UZB) and the Spanish (Se-SP1, Se-SP2, and Se-SP3) isolates from S. exigua showed unrelated REN profiles. However, the Pst I and Bgl II profiles of Se-UZB and Mb-PL were identical, and very similar to the REN profiles of the MbMNPV strain, which constitutes the active component of Mamestrin^® (NPP, Nagueres, France), a commercial bioinsecticide. It is therefore very likely that the Se-UZB samples were cross-infected by the Polish strain (Mb-PL). This work presents two new strains of SeMNPV and MbMNPV, called Se-SP3 and Mb-PL, respectively, which were surveyed in two distant areas.     

Efficient reverse-engineering of a developmental gene regulatory network

Understanding the complex regulatory networks underlying development and evolution of multi-cellular organisms is a major problem in biology. Computational models can be used as tools to extract the regulatory structure and dynamics of such networks from gene expression data. This approach is called reverse engineering. It has been successfully applied to many gene networks in various biological systems. However, to reconstitute the structure and non-linear dynamics of a developmental gene network in its spatial context remains a considerable challenge. Here, we address this challenge using a case study: the gap gene network involved in segment determination during early development of Drosophila melanogaster. A major problem for reverse-engineering pattern-forming networks is the significant amount of time and effort required to acquire and quantify spatial gene expression data. We have developed a simplified data processing pipeline that considerably increases the throughput of the method, but results in data of reduced accuracy compared to those previously used for gap gene network inference. We demonstrate that we can infer the correct network structure using our reduced data set, and investigate minimal data requirements for successful reverse engineering. Our results show that timing and position of expression domain boundaries are the crucial features for determining regulatory network structure from data, while it is less important to precisely measure expression levels. Based on this, we define minimal data requirements for gap gene network inference. Our results demonstrate the feasibility of reverse-engineering with much reduced experimental effort. This enables more widespread use of the method in different developmental contexts and organisms. Such systematic application of data-driven models to real-world networks has enormous potential. Only the quantitative investigation of a large number of developmental gene regulatory networks will allow us to discover whether there are rules or regularities governing development and evolution of complex multi-cellular organisms.     

Expression of 5HT-1A and 5HT-1B receptor genes in brains of Wistar-Zagreb 5HT rats

By selective breeding, two sublines of rats with high or low activity of platelet serotonin (5HT) transporter (5HTt) have been developed (Wistar-Zagreb 5HT rats). Previous studies demonstrated significant differences between the sublines in the expression of platelet 5HTt at the level of both, mRNA and protein. Pharmacological studies showed marked alterations in brain 5HTt function, indicating differences in central serotonin homeostasis, although analysis of regional brain 5HTt gene expression did not show analogous differences. In this study, we searched for possible changes in the expression of the two central 5HT receptor subtypes: 5HT-1A and 5HT-1B, both participating in the regulation of brain 5HT transmission. Semi-quantitative RT-PCR, with three different housekeeping genes as internal standards, showed no differences in the levels of 5HT-receptor expression between the sublines. Results suggest that constitutional alteration of 5HT homeostasis, induced by selective breeding for the extremes of platelet 5HTt activity, did not cause measurable changes in the expression of central 5HT-1A (hippocampus) and 5HT-1B (striatum) receptors in the mentioned rat sublines under physiological conditions.     

Technical variations of the bipedicled TRAM flap in unilateral breast reconstruction: effects of conventional versus microsurgical techniques of pedicle transfer on complications rates

In cases of unilateral breast reconstruction with a transverse rectus abdominis musculocutaneous (TRAM) flap, poorly perfused tissue, which is normally excised to avoid subsequent fat necrosis, must sometimes be used to achieve adequate breast size and projection. In such cases, incorporation of a second vascular pedicle into the flap design improves perfusion. The authors retrospectively examined their experience with bipedicled TRAM flap-based unilateral breast reconstruction to determine whether the use of microsurgical rather than conventional (nonmicrosurgical) techniques for flap transfer resulted in lower incidences of flap-site fat necrosis and donor-site hernia/bulge. The authors retrospectively reviewed the medical records of all patients who underwent unilateral breast reconstruction with a bipedicled TRAM or deep inferior epigastric perforator flap between January of 1991 and March of 2001. Group 1 consisted of patients who had undergone flap transfer using a conventional technique for both pedicles; group 2, patients who had flap transfer using a conventional technique for one pedicle and a microsurgical technique for the other; and group 3, patients who had flap transfer using a microsurgical technique for both pedicles. Of the 863 patients identified, 72 (8.3 percent) had undergone reconstruction using a bipedicled flap. There were 43 patients in group 1, 24 patients in group 2, and five patients in group 3. Only one case of total flap loss had occurred (group 1). Partial flap loss occurred in two patients in group 1 (5 percent) and three patients in group 2 (13 percent). Fat necrosis occurred more frequently in groups 1 (23 percent) and 2 (29 percent) than in group 3 (0 percent) (p = 0.5, Fisher's exact test). Similarly, bulge or hernia was more common in groups 1 (12 percent) and 2 (4 percent) than in group 3 (0 percent) (p = 0.6, Fisher's exact test). In this study, patients who received a bipedicled TRAM flap using microsurgical techniques alone (group 3) appeared to have better flap perfusion and less frequent hernia/bulge than did patients who underwent flap transfer using conventional (group 1) or combined techniques (group 2). However, these differences were not statistically significant, and this trend must be verified in a larger study.     

Efficacy and safety of rivastigmine in patients with Alzheimer's disease: international randomised controlled trial

ObjectivesTo assess the effects of rivastigmine on the core domains of Alzheimer’s disease.DesignProspective, randomised, multicentre, double blind, placebo controlled, parallel group trial. Patients received either placebo, 1-4 mg/day (lower dose) rivastigmine, or 6-12 mg/day (higher dose) rivastigmine. Doses were increased in one of two fixed dose ranges (1-4 mg/day or 6-12 mg/day) over the first 12 weeks with a subsequent assessment period of 14 weeks.Setting45 centres in Europe and North America.Participants725 patients with mild to moderately severe probable Alzheimer’s disease diagnosed according to the Diagnostic and Statistical Manual of Mental Disorders, fourth edition, and the criteria of the National Institute of Neurological and Communicative Disorders and Stroke and the Alzheimer’s Disease and Related Disorders Association.ResultsAt the end of the study cognitive function had deteriorated among those in the placebo group. Scores on the Alzheimer’s disease assessment scale improved in patients in the higher dose group when compared with patients taking placebo (P<0.05). Significantly more patients in the higher dose group had improved by 4 points or more than had improved in the placebo group (24% (57/242) v 16% (39/238)). Global function as rated by the clinician interview scale had significantly improved among those in the higher dose group compared with those taking placebo (P<0.001), and significantly more patients in the higher dose group showed improvement than did in the placebo group (37% (80/219) v 20% (46/230)). Mean scores on the progressive deterioration scale improved from baseline in patients in the higher dose group but fell in the placebo group. Adverse events were predominantly gastrointestinal, of mild to moderate severity, transient, and occurred mainly during escalation of the dose. 23% (55/242) of those in the higher dose group, 7% (18/242) of those in the lower dose group, and 7% (16/239) of those in the placebo group discontinued treatment because of adverse events.ConclusionsRivastigmine is well tolerated and effective. It improves cognition, participation in activities of daily living, and global evaluation ratings in patients with mild to moderately severe Alzheimer’s disease. This is the first treatment to show compelling evidence of efficacy in a predominantly European population.

Key messages

• In a 6 month trial rivastigmine was effective in treating the core cognitive and functional symptoms of patients with mild to moderate Alzheimer’s disease
• Rivastigmine at doses of 6-12 mg/day produces clinically relevant and statistically significant improvements in cognitive and global assessments, and in activities of daily living
• The effects of rivastigmine are dose dependent
• Rivastigmine was well tolerated in this population of elderly patients

     

Microorganisms,nematodes and parasitoids of Ocnogyna baetica (Rambur) (lep.: Arctiidae) in Southern Spain with potential for use in biological control

Populations of Ocnogyna baetica were sampled during 1989–92 in various provinces of Southern Spain for the presence of pathogenic microorganisms, nematodes and parasitic insects. A total number of 8615 larvae have been diagnosed among which the following biotic factors have been encountered and identified: viruses (Baculovirus sp. Entomopoxvirus sp.), fungus (Beauveria bassiana), mermithid (Hexamermis sp.), braconids (Cotesia plutellae, Glyptapanteles compressiventris, Meteorus versicolor), tachinids (Chaetogena obliquata, Tryphera lugubris. These pathogens and parasitoids represent new species that have not been reported in Spain or in O. baetica before. Data on their contribution to host mortality is presented.     

Targeted deletion of regions rich in immune-evasive genes from the cytomegalovirus genome as a novel vaccine strategy

Human cytomegalovirus (CMV), a ubiquitous human pathogen, is a leading cause of congenital infections and represents a serious health risk for the immunosuppressed patient. A vaccine against CMV is currently not available. CMV is characterized by its large genome and by multiple genes modulating the immunity of the host, which cluster predominantly at genome termini. Here, we tested whether the deletion of gene blocks rich in immunomodulatory genes could be used as a novel concept in the generation of immunogenic but avirulent, herpesvirus vaccines. To generate an experimental CMV vaccine, we selectively deleted 32 genes from the mouse cytomegalovirus (MCMV) genome. The resulting mutant grew to titers similar to that of wild-type MCMV in vitro. In vivo, the mutant was 10,000-fold attenuated and well tolerated, even by highly susceptible mice deficient for B, T, and NK cells or for the interferon type I receptor. Equally relevant for safety concerns, immune suppression did not lead to the mutant's reactivation from latency. Immunization with the replication-competent mutant, but not with inactivated virus, resulted in protective immunity, which increased over time. Vaccination induced MCMV-specific antibodies and a strong T-cell response. We propose that a targeted and rational approach can improve future herpesvirus vaccines and vaccine vectors.     

Cytomegalovirus subverts macrophage identity

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A simple and reliable method for monitoring platelet serotonin levels in rats

A simple and reliable method for individual monitoring of platelet serotonin in rats is developed. Platelet-rich plasma is prepared under standardized conditions from 1 mL of venous blood and the platelets are quantitatively separated by a highly reproducible procedure. Platelet serotonin content is determined spectrophotofluorometrically and the results are comparatively expressed per standardized platelet rich plasma sample (1.01 +/- 0.18 microgram), per mg of platelet protein (1.57 +/- 0.15 microgram) and per 10(9) platelets (2.16 +/- 0.38 micrograms). Normal distribution of platelet serotonin levels in a sample of 338 animals is shown. By use of the described method, the intraindividual stability of platelet serotonin concentration in rats is demonstrated for the first time.