Spectroscopic study of permanganate oxidation reactions of oligonucleotides containing single base mismatches

The electrophoretic gel-based chemical cleavage of the mismatch method gives an incomplete view of the DNA conformational changes induced by a single base mismatch. This spectroscopic study investigates the permanganate oxidation reactions with matched and mismatched DNA under constant and variable temperature conditions. The results, which include the oxidation levels, reaction patterns with isosbestic points, color changes, thermal spectra, spectroscopy derivative, and gel separation and melting temperatures, provide a fundamental background for identification of oligonucleotides containing single base mismatches by chemical means.     

Application of Vascular Puncture for Evaluation of Curtovirus Resistance in Chile Pepper and Tomato

Curtoviruses cause severe damage to tomatoes and peppers. Functional field resistance to curtoviruses in these plants is desirable but difficult to produce and difficult to screen for because it is time‐consuming and resistance could be achieved by developing resistance either to the virus or to insect feeding. To improve and speed curtovirus resistance testing in tomato (Solanum lycopersicum) and pepper (Capsicum annuum) plants, two puncture methods were developed and compared to leafhopper inoculation and feeding preference assays. The two puncture methods were adapted to introduce a modified Agrobacterium tumefaciens plasmid carrying a recombinant curtovirus into the meristem tissue of tomato plants and into newly germinated chile pepper seedlings. The puncture techniques were used to screen for resistance to curtoviruses in chile pepper and tomato breeding lines and varieties. Similarly, the peppers and tomatoes were assayed for curtovirus resistance using leafhopper inoculation and feeding preference, which was assessed by stylet sheath staining. Virus infection by puncture and leafhopper feeding was monitored using PCR and ELISA. ELISA was performed using an antibody to bacterially expressed coat protein. While pepper cvs Tabasco, NuMex Las Cruces cayenne and New Mexico 6‐4 were infected using both puncture and leafhopper inoculation methods, New Mexico 6‐4 had higher infection rates than the other two cultivars. Stylet sheath staining results suggest that leafhoppers prefer to feed on New Mexico 6‐4 rather than Tabasco and NuMex Las Cruces cayenne. Eight tomato cultivars were infected using meristem removal injection inoculation. Three tomatoes cultivars (CVF‐11, Saladmaster and Supersteak) were infected using leafhopper inoculation, although stylet sheath staining results suggested that the first two cultivars were not preferred by the insect vector. Our results suggest that puncture methods and leafhopper inoculation are successful in resistance screening, and both methods should be used as part of screening, because they assess different types of resistance.     

5,5′- and 6,6′-Dialkyl-5,6-dihydro-1H-pyridin-2-ones as potent inhibitors of HCV NS5B polymerase

The discovery of 5,5′- and 6,6′-dialkyl-5,6-dihydro-1H-pyridin-2-ones as potent inhibitors of the HCV RNA-dependent RNA polymerase (NS5B) is described. Several of these agents also display potent antiviral activity in cell culture experiments (EC₅₀ <0.10 μM). In vitro DMPK data for selected compounds as well as crystal structures of representative inhibitors complexed with the NS5B protein are also disclosed.     

New data on morphology,distribution, and relationship of two Asian endemics Netzelia tuberspinifera and Netzelia mulanensis (Amoebozoa: Arcellinida) co-existing in the largest natural freshwater lake of Vietnam

Limnology - Data on the distribution and species-environment relationships of rare and endemic species of protists in Asian tropical waterbodies could provide valuable information for better...     

Variation in pollinator-mediated plant reproduction across an urbanization gradient

Oecologia - Urbanization alters the landscape, degrades and fragments habitats, and can have a profound effect on species interactions. Plant–pollinator networks may be particularly sensitive...     

Expression pattern and raft association of NIPSNAP3 and NIPSNAP4, highly homologous proteins encoded by genes in close proximity to the ATP-binding cassette transporter A1

The highly homologous genes NIPSNAP3 and NIPSNAP4, with 87% amino acid identity, are members of the NIPSNAP family with putative roles in vesicular trafficking. NIPSNAP3 mRNA and NIPSNAP4 mRNA and protein were detected in multiple tissues and cells at varying degrees. Interestingly, NIPSNAP3 is most highly expressed in skeletal muscle, where NIPSNAP4 has a low mRNA abundance. NIPSNAP4 was found associated with membranes and partly localized in rafts. The ubiquitous expression of the highly conserved NIPSNAPs and their association with membranes further support an important cellular function of these proteins probably linked to vesicular trafficking. The NIPSNAP3 and NIPSNAP4 genes are located in close proximity to the 3' end of the ATP-binding cassette transporter A1 (ABCA1), whose mutations cause familial high-density lipoprotein deficiency syndromes. The adjacent genomic location and the finding that ABCA1 is a regulator of vesicular trafficking may indicate a functional relation of these proteins, even though NIPSNAP4 does not interact directly with ABCA1 nor is its expression altered in cells with mutated ABCA1.     

Developing the ethics of implementation research in health

Implementation research (IR) is growing in recognition as an important generator of practical knowledge that can be translated into health policy. With its aim to answer questions about how to improve access to interventions that have been shown to work but have not reached many of the people who could benefit from them, IR involves a range of particular ethical considerations that have not yet been comprehensively covered in international guidelines on health research ethics. The fundamental ethical principles governing clinical research apply equally in IR, but the application of these principles may differ depending on the IR question, context, and the nature of the proposed intervention. IR questions cover a broad range of topics that focus on improving health system functioning and improving equitable and just access to effective health care interventions. As such, IR designs are flexible and often innovative, and ethical principles cannot simply be extrapolated from their applications in clinical research. Meaningful engagement with all stakeholders including communities and research participants is a fundamental ethical requirement that cuts across all study phases of IR and links most ethical concerns. Careful modification of the informed consent process may be required in IR to permit study of a needed intervention. The risks associated with IR may be difficult to anticipate and may be very context-specific. The benefits of IR may not accrue to the same groups who participate in the research, therefore justifying the risks versus benefits of IR may be ethically challenging. The expectation that knowledge generated through IR should be rapidly translated into health policy and practice necessitates up-front commitments from decision-makers to sustainability and scalability of effective interventions. Greater awareness of the particular ethical implications of the features of IR is urgently needed to facilitate optimal ethical conduct of IR and uniform ethical review.