Structure-guided design and optimization of small molecules targeting the protein-protein interaction between the von hippel-lindau (VHL) E3 ubiquitin ligase and the hypoxia inducible factor (HIF) alpha subunit with in vitro nanomolar affinities

E3 ubiquitin ligases are attractive targets in the ubiquitin-proteasome system, however, the development of small-molecule ligands has been rewarded with limited success. The von Hippel-Lindau protein (pVHL) is the substrate recognition subunit of the VHL E3 ligase that targets HIF-1α for degradation. We recently reported inhibitors of the pVHL:HIF-1α interaction, however they exhibited moderate potency. Herein, we report the design and optimization, guided by X-ray crystal structures, of a ligand series with nanomolar binding affinities

Early parenting intervention: Family risk and first-time parenting related to intervention effectiveness

The effects of cumulative risk and parity on the effectiveness of a home based parenting intervention were tested in a randomized controlled trial with 237 families with 1- to 3-year-old children screened for high levels of externalizing behavior. The intervention was aimed at enhancing positive parenting and decreasing externalizing behaviors. The results showed that cumulative risk was not associated with either change in child externalizing behaviors or change in positive parenting. When intervention effectiveness was compared for primiparas (i.e., first-time mothers) versus multiparas (i.e., mothers with more than one child), we found that intervention mothers of first-born children displayed an increase in their use of positive discipline strategies as compared to first-time mothers in the control group, whereas a similar effect for multiparas was absent. Among multiparas we found an intervention effect on sensitivity, with control group mothers showing an increase in sensitivity, whereas the intervention group showed a constant level of sensitivity over time. These results suggest that parity may be a moderator of intervention effectiveness. Implications for investigating moderators of intervention effectiveness are discussed. © 2007 Springer Science+Business Media, LLC

Effects of Net Depth Reduction to Bigeye Tuna (Thunnus obesus) Catch

Analysis on the catch of Bigeye tuna (Thunnus obesus) from purse seine and ring nets of various net depths was conducted to assess the effect of reducing net depth as a compatible measure the Philippines has implemented and reducing the catch of Bigeye in its internal waters and the Exclusive Economic Zone (EEZ). The study was based on observer reports from ring net and purse seine fishing vessels operating in internal waters and EEZ as well as from group seine operations in the high seas pocket 1. Nets were classed by depth to determine and compare variations on the catch of Bigeye, catch rates and relative proportion, species composition, and fishing grounds. Results indicated that the catch of Bigeye is correlated with the depth of net, with a significantly higher catch of Bigeye in deeper nets. The result of the study is consistent with other studies elsewhere, and in consonance with the implementation of Fisheries Administrative Order 236 limiting the depth to 115 fathoms for ring net and purse seine operating in Philippine internal waters and the EEZ as a compatible measure to reduce the catch of Bigeye

Can Non-lytic CD8+T Cells Drive HIV-1 Escape?

The CD8+ T cell effector mechanisms that mediate control of HIV-1 and SIV infections remain poorly understood. Recent work suggests that the mechanism may be primarily non-lytic. This is in apparent conflict with the observation that SIV and HIV-1 variants that escape CD8+ T cell surveillance are frequently selected. Whilst it is clear that a variant that has escaped a lytic response can have a fitness advantage compared to the wild-type, it is less obvious that this holds in the face of non-lytic control where both wild-type and variant infected cells would be affected by soluble factors. In particular, the high motility of T cells in lymphoid tissue would be expected to rapidly destroy local effects making selection of escape variants by non-lytic responses unlikely. The observation of frequent HIV-1 and SIV escape poses a number of questions. Most importantly, is the consistent observation of viral escape proof that HIV-1- and SIV-specific CD8+ T cells lyse infected cells or can this also be the result of non-lytic control? Additionally, the rate at which a variant strain escapes a lytic CD8+ T cell response is related to the strength of the response. Is the same relationship true for a non-lytic response? Finally, the potential anti-viral control mediated by non-lytic mechanisms compared to lytic mechanisms is unknown. These questions cannot be addressed with current experimental techniques nor with the standard mathematical models. Instead we have developed a 3D cellular automaton model of HIV-1 which captures spatial and temporal dynamics. The model reproduces in vivo HIV-1 dynamics at the cellular and population level. Using this model we demonstrate that non-lytic effector mechanisms can select for escape variants but that outgrowth of the variant is slower and less frequent than from a lytic response so that non-lytic responses can potentially offer more durable control

Essential Oil of Cymbopogon winterianus Jowitt from Tanzania: Composition and Antimicrobial Activity

The hydro-distilled essential oil (1.6%) of fresh aerial parts of wild Cymbopogon winterianus Jowitt was analyzed by GC-MS. Fifty compounds representing 96.5% of the oil were identified. The main components of the oil were linalool (27.4%), citronellol (10.9%), geraniol (8.5%), α-calacorene, cis-calamenene (4.3%), β-elemene (3.9%) and longifolene (3.5%). The oil exhibited low antimicrobial activity.Fil: Malele, R. S.. University of Dar Es Salaam; TanzaniaFil: Mwangi, J. W.. University of Nairobi; KeniaFil: Thoithi, G. N.. University of Nairobi; KeniaFil: Kibwage, I. O.. University of Nairobi; KeniaFil: López, M. L.. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; ArgentinaFil: Zunino, María Paula. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; ArgentinaFil: López, A. G.. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; ArgentinaFil: Zygadlo, Julio Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; ArgentinaFil: Oliva, Maria de Las Mercedes. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; Argentina. Universidad Nacional de Río Cuarto; ArgentinaFil: Demo, M. S.. Universidad Nacional de Río Cuarto; Argentin