Sphecid wasps (Hymenoptera: Apoidea: Sphecidae) as potential control agents of acridid pests (Orthoptera: Acrididae) in Ethiopia

The possibility of using sphecid wasps to control acridid pests is discussed. A list of 19 Ethiopian species that could be utilized for this purpose is provided.     

Phytoavailability of Heavy Metals and Metalloids in Soils Irrigated with Wastewater,Akaki, Ethiopia: A Greenhouse Study

Irrigation with untreated wastewater from several industrial, commercial, and domestic discharges for decades caused accumulation of various heavy metals and metalloids in soils along the Akaki River in Ethiopia. Assessment of environmental threats and the potential phytoremediation of the soils require understanding of the toxic elements’ uptake and distribution in plant parts. Hence, a greenhouse study was performed to examine the phytoavailability and distribution of Cr, Ni, Co, Cu, Zn, Cd, Pb, Hg, Se, V, and As in forage grasses: Oat (Avena sativa), Rhodes grass (Chloris gayana), Setaria (Setaria sphacelata), and the legumes Alfalfa (Medicago sativa) and Desmodium (Desmodium unicinatum). The average contents of Cr, Ni, Co, Cu, Zn, Pb, Hg, Se, and V in the plants were generally higher than the background levels for forage grasses/legumes, and some of these elements were in the phytotoxic range. Root bioconcentration factor (BCF = root to soil concentration ratio) > 1 was observed for Cu (Oat, Rhodes, Desmodium, and Setaria: Fluvisol), Zn (Setaria: Fluvisol), Cd (Rhodes: Fluvisol; Setaria from both soils) and Hg (Oat and Alfalfa: Fluvisol). Alfalfa and Desmodium displayed translocation factor > 1 (TF = shoot to root concentration ratio) for most heavy metals. Most heavy metals/metalloids may pose a health threat to humans and stock via introduction to the food chain. The plant factors (species and plant part), soil factors (soil type, soil fractions, pH, and CEC), and their interactions significantly (p < 0.05) influenced plant heavy metal and metalloid levels. However, the role of plant part and species emerged as the most important on heavy metal uptake, translocation, sequestration, and ultimately transfer to the food chain. Accordingly, the uptake and distribution of heavy metals/metalloids in the plants reflect the potential environmental and health hazards attributable to the use of fodder grasses, legumes, and cultivation of vegetables in soils with polymetallic and metalloid contamination.     

Cooperation in Health: Mapping Collaborative Networks on the Web

Objective

To map and investigate the relationships established on the web between leading health-research institutions around the world.

Methods

Sample selection was based on the World Health Organization (WHO) Collaborating Centres (CCs). Data on the 768 active CCs in 89 countries were retrieved from the WHO''s database. The final sample consisted of 190 institutions devoted to health sciences in 42 countries. Data on each institution''s website were retrieved using webometric techniques (interlinking), and an asymmetric matrix was generated for social network analysis.

Findings

The results showed that American and European institutions, such as the Centers for Disease Control and Prevention (CDC), the National Institutes of Health (NIH) and the National Institute of Health and Medical Research (INSERM), are the most highly connected on the web and have a higher capacity to attract hyperlinks. The Karolinska Institute (KI-SE) in Sweden is well placed as an articulation point between several integrants of the network and the component''s core but lacks general recognition on the web by hyperlinks. Regarding the north-south divide, Mexico and Brazil appear to be key southern players on the web. The results showed that the hyperlinks exchanged between northern and southern countries present an abysmal gap: 99.49% of the hyperlinks provided by the North are directed toward the North itself, in contrast to 0.51% that are directed toward the South. Regarding the South, its institutions are more connected to its northern partners, with 98.46% of its hyperlinks directed toward the North, and mainly toward the United States, compared with 1.54% toward southern neighbors.

Conclusion

It is advisable to strengthen integration policies on the web and to increase web networking through hyperlink exchange. In this way, the web could actually reflect international cooperation in health and help to legitimize and enhance the visibility of the many existing south-south collaboration networks.     

Insights into Distinct Modulation of α7 and α7β2 Nicotinic Acetylcholine Receptors by the Volatile Anesthetic Isoflurane

Nicotinic acetylcholine receptors (nAChRs) are targets of general anesthetics, but functional sensitivity to anesthetic inhibition varies dramatically among different subtypes of nAChRs. Potential causes underlying different functional responses to anesthetics remain elusive. Here we show that in contrast to the α7 nAChR, the α7β2 nAChR is highly susceptible to inhibition by the volatile anesthetic isoflurane in electrophysiology measurements. Isoflurane-binding sites in β2 and α7 were found at the extracellular and intracellular end of their respective transmembrane domains using NMR. Functional relevance of the identified β2 site was validated via point mutations and subsequent functional measurements. Consistent with their functional responses to isoflurane, β2 but not α7 showed pronounced dynamics changes, particularly for the channel gate residue Leu-249(9′). These results suggest that anesthetic binding alone is not sufficient to generate functional impact; only those sites that can modulate channel dynamics upon anesthetic binding will produce functional effects.     

Recognition of a genus-wide antigen ofLegionella by a monoclonal antibody

A monoclonal antibody was produced against a cytoplasmic membrane protein that appears to be common to all species of the genusLegionella. The antibody was positive in polyacrylamide gel electrophoresis and Western blotting with extracts of all of 22 species type strains ofLegionella that were tested. The apparent molecular mass of the protein varied from 57.2 to 62.1 kilodaltons for the 23 species type strains ofLegionella. An enzyme-linked immunosorbent assay (ELISA) was developed with the monoclonal antibody to enable rapid screening of clinical and environmental isolates forLegionella. All of 23 species type strains ofLegionella that were tested were strongly positive with the monoclonal antibody in the ELISA. Among 27 other bacterial species and 84 strains that were tested, onlyBordetella ssp. andAcinetobacter lwoffii were cross-reactive in the ELISA. These two cross-reactive species are readily distinguishable fromLegionella by culture characteristics. The monoclonal antibody may also be useful in tests to detect the genus-wide antigen in body fluids of patients with legionellosis.     

Modeling human muscle disease in zebrafish

Zebrafish reproduce in large quantities, grow rapidly, and are transparent early in development. For these reasons, zebrafish have been used extensively to model vertebrate development and disease. Like mammals, zebrafish express dystrophin and many of its associated proteins early in development and these proteins have been shown to be vital for zebrafish muscle stability. In dystrophin-null zebrafish, muscle degeneration becomes apparent as early as 3 days post-fertilization (dpf) making the zebrafish an excellent organism for large-scale screens to identify other genes involved in the disease process or drugs capable of correcting the disease phenotype. Being transparent, developing zebrafish are also an ideal experimental model for monitoring the fate of labeled transplanted cells. Although zebrafish dystrophy models are not meant to replace existing mammalian models of disease, experiments requiring large numbers of animals may be best performed in zebrafish. Results garnered from using this model could lead to a better understanding of the pathogenesis of the muscular dystrophies and the development of future therapies.     

Incidence and tracking of Escherichia coli O157:H7 in a major produce production region in California

Fresh vegetables have become associated with outbreaks caused by Escherichia coli O157:H7 (EcO157). Between 1995-2006, 22 produce outbreaks were documented in the United States, with nearly half traced to lettuce or spinach grown in California. Outbreaks between 2002 and 2006 induced investigations of possible sources of pre-harvest contamination on implicated farms in the Salinas and San Juan valleys of California, and a survey of the Salinas watershed. EcO157 was isolated at least once from 15 of 22 different watershed sites over a 19 month period. The incidence of EcO157 increased significantly when heavy rain caused an increased flow rate in the rivers. Approximately 1000 EcO157 isolates obtained from cultures of>100 individual samples were typed using Multi-Locus Variable-number-tandem-repeat Analysis (MLVA) to assist in identifying potential fate and transport of EcO157 in this region. A subset of these environmental isolates were typed by Pulse Field Gel Electrophoresis (PFGE) in order to make comparisons with human clinical isolates associated with outbreak and sporadic illness. Recurrence of identical and closely related EcO157 strains from specific locations in the Salinas and San Juan valleys suggests that transport of the pathogen is usually restricted. In a preliminary study, EcO157 was detected in water at multiple locations in a low-flow creek only within 135 meters of a point source. However, possible transport up to 32 km was detected during periods of higher water flow associated with flooding. During the 2006 baby spinach outbreak investigation, transport was also detected where water was unlikely to be involved. These results indicate that contamination of the environment is a dynamic process involving multiple sources and methods of transport. Intensive studies of the sources, incidence, fate and transport of EcO157 near produce production are required to determine the mechanisms of pre-harvest contamination and potential risks for human illness.     

Ten di- and trinucleotide microsatellite loci in the Caribbean spiny lobster, Panulirus argus, for studies of regional population connectivity

We describe 10 microsatellite loci for Panulirus argus (Caribbean spiny lobster). The number of alleles at each locus ranged from four to 39 (mean = 21.8) in 89 juvenile specimens collected at two different times at a recruitment site in south Florida. Levels of expected and observed heterozygosities ranged from 0.48 to 0.96 (mean = 0.83) and from 0.32 to 0.98 (mean = 0.71), respectively. Significant departures from Hardy–Weinberg equilibrium were observed at two loci. There was no evidence of genotypic disequilibrium for any pair of loci. Overall, the loci were well resolved, highly polymorphic and independently segregating, confirming their utility for population genetic studies.     

Development of 15 polymorphic microsatellite markers in the Atlantic tarpon (Megalops atlanticus) for capture-recapture studies

Fifteen polymorphic microsatellite DNA loci for Atlantic tarpon, Megalops atlanticus, were isolated by using PIMA, a polymerase chain reaction‐based technique. The number of alleles at each locus ranged from two to 24 (mean = 7.7) in 65 specimens from Tampa Bay, Florida. Observed and expected heterozygosities ranged from 0.27 to 0.92 (mean = 0.60) and from 0.28 to 0.95 (mean = 0.62), respectively. Genotypes at one locus deviated significantly from Hardy–Weinberg equilibrium. In exact tests for genotypic disequilibrium, there was no evidence of associations between any pair of loci. Overall, loci were well resolved and highly polymorphic, confirming their suitability for DNA fingerprinting applications and other genetic studies.     

PERMANENT GENETIC RESOURCES: Twelve polymorphic microsatellite markers for the bonefish, Albula vulpes and two congeners

Twelve polymorphic microsatellite loci were isolated for the bonefish, Albula vulpes using a polymerase chain reaction‐based procedure. The number of alleles ranged from two to 23 (mean = 8.8) in 37 specimens from south Florida. Observed and expected heterozygosities ranged from 0.07 to 0.77 (mean = 0.42) and from 0.07 to 0.84 (mean = 0.48), respectively. There were no significant departures from Hardy–Weinberg equilibrium and no evidence of genotypic disequilibrium between any pair of loci. In a cross‐amplification test, all markers yielded appropriately sized alleles for specimens of the provisional Albula sp. B and 11 of the 12 loci amplified for those of Albula glossodonta.