Synthesis of Several 2′-Deoxy-3-Alkyl(ARYL)-3-Deazaguanosines: Mild Alkylation of a Cyanomethyl Imidazole with Electrophiles

Abstract

The synthesis of several 2′-deoxy-3-alkyl(aryl)-3-deazaguanosines and of their heterocyclic aglycone is described. The 2-(1-napthyl)ethyl substituent group induces an unnatural 3′-endo/high-anti (-sc) conformation of the nucleoside.     

Carbon monoxide prevents hepatic mitochondrial membrane permeabilization

Background  

Low concentrations of carbon monoxide (CO) protect hepatocytes against apoptosis and confers cytoprotection in several models of liver. Mitochondria are key organelles in cell death control via their membrane permeabilization and the release of pro-apoptotic factors.     

Six recommendations for improving monitoring of diseases shared with wildlife: examples regarding mycobacterial infections in Spain

Monitoring is needed to identify changes in disease occurrence and to measure the impact of intervention. Using mycobacterial diseases as an example, we discuss herein the pros and cons of the current Spanish Wildlife Disease Surveillance Scheme providing suggestions for monitoring relevant diseases shared with wildlife in other regions facing similar challenges. Six points should be considered. This includes: (1) making sure the disease is properly monitored in the relevant domestic animals or even in humans; (2) also making sure that background information on wildlife population ecology is available to maximize the benefits of the monitoring effort; (3) selecting the appropriate wildlife hosts for monitoring, while being flexible enough to incorporate new ones if research suggests their participation; (4) selecting the appropriate methods for diagnosis and for time and space trend analysis; (5) deciding which parameters to target for monitoring; and finally (6) establishing a reasonable sampling effort and a suitable sampling stratification to ensure detecting changes over time and changes in response to management actions. Wildlife disease monitoring produces knowledge that benefits at least three different agencies, namely, animal health, public health and conservation, and these should combine efforts and resources. Setting up stable, comprehensive and accurate schemes at different spatial scales should become a priority. Resources are always a limiting factor, but experience shows that combined, cross-collaborative efforts allow establishing acceptable schemes with a low enough cost to be sustainable over time. These six steps for monitoring relevant shared diseases can be adapted to many other geographical settings and different disease situations.     

Spatio-Temporal Trends of Iberian Wild Boar Contact with Mycobacterium tuberculosis Complex Detected by ELISA

The continuing expansion of Eurasian wild boar (Sus scrofa) populations raises concerns regarding disease transmission. In south-central Spain, overabundant wild boar are reservoirs of Mycobacterium bovis, and related members of the Mycobacterium tuberculosis complex (MTBC), the causative agents of bovine tuberculosis (bTB). An indirect enzyme-linked immunosorbent assay using bovine-purified protein derivative was applied to determine the spatial and temporal distribution of wild boar contact with MTBC in the Iberian Peninsula and to model and identify the associated risk factors. Wild boar apparent seroprevalence was 22%. Seropositives were detected in 71% of 81 sites, including 23 sites where wildlife was thought to be bTB free. The results described a new geographic range of wild boar contact with MTBC and a stable prevalence in this wildlife reservoir that contrasts with the success of bTB control in cattle. Inference of which host (wild boar or cattle) is driving bTB maintenance was not possible with our correlational results. The possibility of a wild boar bTB emergence in non-endemic regions should urgently be taken into account to avoid a future scenario resembling the current situation in south-central Spain.     

Temporal and spatial patterns in ichthyoplankton assemblages in bay and open coastal environments

The larval fish fauna occurring in temperate bay and shelf waters off Victoria, southern Australia, was found to be diverse, comprising taxa from 52 families. The most abundant groups collected were gobiids, tripterygiids, gobiesocids and clupeids. Fish egg concentrations were highest during spring and summer (September to February). Eggs of the Australian anchovy Engraulis australis occurred mainly during spring (September to November). Total larval fish concentrations were highest during summer (December to February), and were significantly higher at 1 km than 2 and 5 km from shore in offshore samples. Larval concentrations of a number of families, mainly reef‐associated taxa that attach their eggs to hard substrata, were also higher nearer to shore. These larvae are more developed upon hatching than those of pelagic spawners and more capable of avoiding passive drift. Multivariate analyses found that larval taxonomic composition did not vary significantly with distance from shore, but that seasonal and monthly groupings were evident, with different taxa dominating at different times of the year. Larvae of the families Gobiidae and Tripterygiidae occurred in all months, but were less abundant during winter. Spatial differences in the larval fish assemblage between offshore samples and samples taken in the bay were only apparent during summer. This was primarily due to a higher abundance of seagrass‐associated species, such as syngnathids and hemiramphids, utilizing specific habitats in the bay.     

Morphometric relationships for some species of elasmobranch from tropical eastern Pacific

This study proposes length relationship equations to determine total length of four species of sharks (Carcharhinus falciformis, Mustelus lunulatus, Sphyrna lewini and Carcharhinus limbatus) based on trunk lengths (TrL) and interdorsal lengths (IL) caught in Colombia and Central America Pacific Ocean. In Central American Pacific, data were recorded for C. falciformis, C. limbatus and S. lewini between 2006 and 2012. In the Colombian Pacific, data was recorded in 1994–1995 and from 2006 to 2012 for C. falciformis, S. lewini and M. lunulatus. In the Central American Pacific the IL – TL relationship was acceptable for C. falciformis (r² = .69) and C. limbatus which presented a good relationship (r² = .81) where most specimens were juveniles; the same trend was found for S. lewini (r² = .96). The TL‐TrL relationship estimated for species caught in the Colombian Pacific was significant for C. falciformis (r² = .98) and for M. lunulatus (r² = .84); however, for S. lewini this relationship was low (r² = .55). Results indicate this is a useful tool for fishery statistics and fishery management for elasmobranch species of the Eastern Tropical Pacific.     

Biochemical and immunological characterization of α-amylase isoenzymes of Araucaria araucana

Seven α-amylase isoenzymes present in quiescent seeds of the South American conifer Araucaria araucana were purified by affinity chromatography and partially characterized. The molecular masses of these isoenzymes were 45.7, 47.0, 50.2, 51.2, 52.0, 53.5 and 55.2 kDa. The two main isoforms were separated from each other and from the rest of the isoenzymes by anion-exchange chromatography using a linear gradient of 0 to 0.6 M NaCl and slightly different CaCl₂ concentrations. All isoenzyme bands stained with periodic acid/dansylhydrazine, suggesting that they are glycoproteins. Electroblotting of the isoenzymes onto polyvinylidene difluoride membranes allowed determination of the amino acid composition and NH₂-terminal sequence of the 53.5-, 50.2-and 47.0-kDa isoenzymes. Amino acid compositional analysis demonstrated that these enzymes are rich in glycine, aspartic acid/asparagine, alanine, serine, proline and glutamic acid/glutamine. The NH₂-terminal sequences of the three isoenzymes are identical. Comparison of the amino acid compositions and the NH₂-terminal sequence of these isoenzymes with the cereal and Vigna radiata α-amylases demonstrated that there is no relation between them. However, polyclonal antibodies generated against barley α-amylase cross-reacted with all the A . araucana α-amylases. Peptide mapping analysis of the isoenzymes using cyanogen bromide suggests that there are genetic differences between them.     

Anatomical,physiological, and biochemical traits involved in the UV-B radiation response in highbush blueberry

The effects of a long-term simulated spring-summer UV-B daily course on some anatomical, physiological, and biochemical features were studied in new and old leaves of blueberry (Vaccinium corymbosum L.) cultivars Legacy, Brigitta, and Bluegold. The results show that under UV-B exposure, leaf thickness increased in Bluegold due to an increased intercellular cavities. By contrast, Brigitta maintained its leaf thickness. The net photosynthetic rate was not significantly affected by the UV-B radiation in any of the cultivars; however, Brigitta presented a better photosystem II performance, since this cultivar had more efficient photochemistry under the UV-B radiation. In addition, Brigitta also maintained enhanced total phenol and total anthocyanin content compared to the other cultivars. In conclusion, Brigitta was more resistant to the UV-B radiation than the other two cultivars.