Expression of baculovirus P35 prevents cell death in Drosophila

The baculovirus P35 protein functions to prevent apoptotic death of infected cells. We have expressed P35 in the developing embryo and eye of the fly Drosophila melanogaster. P35 eliminates most, if not all, normally occurring cell death in these tissues, as well as X-irradiation-induced death. Excess pupal eye cells that are normally eliminated by apoptosis develop into pigment cells when their death is prevented by P35 expression. Our results suggest that one mechanism by which viruses prevent the death of the host cell is to block a cell death pathway that mediates normally occurring cell death. Identification of molecules that interact biochemically or genetically with P35 in Drosophila should provide important insights into how cell death is regulated

Detailed Kinetic Model for the Reaction of Ethene to Propene on Ni/AlMCM-41

The Ni/AlMCM-41 was prepared and applied as the catalyst for the direct conversion of ethene to propene. Based on the results of the broad experimental study, two reaction networks were compared, one consisting of dimerization, isomerization and metathesis and a modified network suggesting the cracking of long-chain olefins. To correlate the experimentally obtained data, the classical Langmuir-Hinshelwood-Hougen-Watson model was applied for both reaction networks. The second network involving catalytic cracking offers a satisfying prediction of the observed product distributions

Corrigendum to ‘‘Alumino-mesostructured Ni catalysts for the direct conversion of ethene to propene” [J. Catal. 305 (2013) 154–168]

Ni/MCM-41 and Ni/AlMCM-41 were synthesized at different Si/Al ratios and tested in the direct conversion of ethene to propene (ETP-reaction). It was intended to evaluate the effect of modifying the catalyst acidity on the ETP-reaction rather than optimizing its performance. All catalysts were characterized by powder XRD, N2-physisorption, 29Si and 27Al MAS NMR, TEM, NH3-TPD, pyridine-DRITFS, H2-TPR, and TPO. Ni/MCM-41 showed low catalytic activity due to its low acidity. Ni/AlMCM-41 catalyst with a Si/Al ratio of 60 had high catalytic activity. Characterization results revealed that the catalyst structure does not have effect on the catalytic activity. Al could be incorporated into the MCM-41 framework up to Si/Al ratio of 16. Two different Ni-composites on the surface of the MCM-41 and AlMCM-41 were observed. Deeper characterization is required to know the Ni state. Important deactivation was observed at 450 °C. The nature of the carbonaceous species and reaction mechanism require deeper characterization

Alumino-mesostructured Ni catalysts for the direct conversion of ethene to propene

Ni/MCM-41 and Ni/AlMCM-41 were synthesized at different Si/Al ratios and tested in the direct conversion of ethene to propene (ETP-reaction). It was intended to evaluate the effect of modifying the catalyst acidity on the ETP-reaction rather than optimizing its performance. All catalysts were characterized by powder XRD, N2-physisorption, 29Si and 27Al MAS NMR, TEM, NH3-TPD, pyridine-DRITFS, H2-TPR, and TPO. Ni/MCM-41 showed low catalytic activity due to its low acidity. Ni/AlMCM-41 catalyst with a Si/ Al ratio of 60 had high catalytic activity. Characterization results revealed that the catalyst structure does not have effect on the catalytic activity. Al could be incorporated into the MCM-41 framework up to Si/Al ratio of 16. Two different Ni-composites on the surface of the MCM-41 and AlMCM-41 were observed. Deeper characterization is required to know the Ni state. Important deactivation was observed at 450 !C. The nature of the carbonaceous species and reaction mechanism require deeper characterization

Simultaneous adsorption of quinoline and dibenzothiophene over Ni-based mesoporous materials at different Si/Al ratio

In this study, two mesoporous materials such as MCM-41 and Ni/MCM-41 were modified with Al at different Si/Al ratios. The mesoporous materials were proved as sorbents of heterocyclic nitrogen and sulfur compounds employing quinoline (Q) and dibenzothiophene (DBT), respectively, as model molecules of that precursor pollutants at the same concentrations of ppmw of nitrogen and sulfur (N:S = 1 ratio). The sample with the highest Si/Al ratio showed the highest specific surface, and at low Si/Al decreased the specific surface. With X-ray diffraction (XRD) the Ni containing in MCM-41, there is a clear trend and the highly hexagonal ordered sample is the one without Al and once the Al is added, the hexagonal ordering is highly modified. Employing NH3-TPD and NMR revealed that the samples with Si/Al = 5 and 16 have higher Lewis acid sites than another ratio of Si/Al. The modification successfully added small amounts of Ni that did not collapse the pore structure but increased the density of surface (acidic) groups that in turn favored the uptake of the sulfur compound through π-complexation adsorption mechanism. It is also possible to recognize that the samples with a Si/Al ratio of 5 and 16 revealed the presence of the highest surface density of weak acid sites for both sorbents. Adsorption experiments were carried out in a batch adsorption system at 313 K and atmospheric pressure using a model mixture from diesel containing: DBT, Q, and 40 ml of dodecane. The sulfur adsorption was substantially improved when Ni was incorporated to MCM-41; for example, at 250 ppmw of N uptake of DBT was almost twice than MCM-41 alone. This result would indicate that Ni/MCM-41 could remove both molecules but mainly the nitrogen molecule at high concentrations. The Langmuir and Freundlich adsorption isotherms were used for all materials considering Q in the presence of DBT depending on the Si/Al ratio. This behavior did not happen for the DBT whose behavior was modelled by an isotherm of the Freundlich type for Ni/MCM-41 and adsorbed in acid sites and multilayer. Lastly, experimental results indicated that MCM-41 with Si/Al = ∞ has the highest (Q/DBT) selectivity of 13,390 at 50 ppmw N compared to another Si/Al ratio, for example, at 250 ppmw N

Emerging executive functioning and motor development in infants at high and low risk for autism spectrum disorder

Existing evidence suggests executive functioning (EF) deficits may be present in children with autism spectrum disorder (ASD) by 3 years of age. It is less clear when, prior to 3 years, EF deficits may emerge and how EF unfold over time. The contribution of motor skill difficulties to poorer EF in children with ASD has not been systematically studied. We investigated the developmental trajectory of EF in infants at high and low familial risk for ASD (HR and LR) and the potential associations between motor skills, diagnostic group, and EF performance. Participants included 186 HR and 76 LR infants. EF (A-not-B), motor skills (Fine and Gross Motor), and cognitive ability were directly assessed at 12 months and 24 months of age. Participants were directly evaluated for ASD at 24 months using DSM-IV-TR criteria and categorized as HR-ASD, HR-Negative, and LR-Negative. HR-ASD and HR-Negative siblings demonstrated less improvement in EF over time compared to the LR-Negative group. Motor skills were associated with group and EF performance at 12 months. No group differences were found at 12 months, but at 24 months, the HR-ASD and HR-Negative groups performed worse than the LR-Negative group overall after controlling for visual reception and maternal education. On reversal trials, the HR-ASD group performed worse than the LR-Negative group. Motor skills were associated with group and EF performance on reversal trials at 24 months. Findings suggest that HR siblings demonstrate altered EF development and that motor skills may play an important role in this process

Screen for Genetic Modifiers of stbm Reveals that Photoreceptor Fate and Rotation Can Be Genetically Uncoupled in the Drosophila Eye

BACKGROUND: Polarity of the Drosophila compound eye arises primarily as a consequence of two events that are tightly linked in time and space: fate specification of two photoreceptor cells, R3 and R4, and the subsequent directional movement of the unit eyes of the compound eye, or ommatidia. While it is thought that these fates dictate the direction of ommatidial rotation, the phenotype of mutants in the genes that set up this polarity led to the hypothesis that these two events could be uncoupled. METHODOLOGY/PRINCIPAL FINDINGS: To definitively demonstrate these events are genetically separable, we conducted a dominant modifier screen to determine if genes, when misexpressed, could selectively enhance subclasses of mutant ommatidia in which the direction of rotation does not follow the R3/R4 cell fates, yet not affect the number of ommatidia in which rotation follows the R3/R4 cell fates. We identified a subset of P element lines that exhibit this selective enhancement. We also identified lines that behave in the opposite manner: They enhance the number of ommatidia that rotate in the right direction, but do not alter the number of ommatidia that rotate incorrectly with respect to the R3/R4 fates. CONCLUSIONS/SIGNIFICANCE: These results indicate that fate and direction of rotation can be genetically separated, and that there are genes that act between R3/R4 fate specification and direction of ommatidial rotation. These data affirm what has been a long-standing assumption about the genetic control of ommatidial polarity

Quality of home-based rapid HIV testing by community lay counsellors in a rural district of South Africa

INTRODUCTION: Lack of universal, annual testing for human immunodeficiency virus (HIV) in health facilities suggests that expansion of HIV testing and counselling (HTC) to non-clinical settings is critical to the achievement of national goals for prevention, care and treatment. Consideration should be given to the ability of lay counsellors to perform home-based HTC in community settings. METHODS: We implemented a community cluster randomized controlled trial of home-based HTC in Sisonke District, South Africa. Trained lay counsellors conducted door-to-door HIV testing using the same rapid tests used by the local health department at the time of the study (SD Bioline and Sensa). To monitor testing quality and counsellor skill, additional dry blood spots were taken and sent for laboratory-based enzyme-linked immunosorbent assay (ELISA) testing. Sensitivity and specificity were calculated using the laboratory result as the gold standard. RESULTS AND DISCUSSION: From 3986 samples, the counsellor and laboratory results matched in all but 23 cases. In 18 cases, the counsellor judged the result as indeterminate, whereas the laboratory judged 10 positive, eight negative and three indeterminate, indicating that the counsellor may have erred on the side of caution. Sensitivity was 98.0% (95% CI: 96.3 98.9%), and specificity 99.6% (95% CI: 99.4 99.7%), for the lay counsellor field-based rapid tests. Both measures are high, and the lower confidence bound for specificity meets the international standard for assessing HIV rapid tests. CONCLUSIONS: These findings indicate that adequately trained lay counsellors are capable of safely conducting high-quality rapid HIV tests and interpreting the results as per the kit guidelines. These findings are important given the likely expansion of community and home-based testing models and the shortage of clinically trained professional staff.Department of HE and Training approved lis