Aquatic grazers reduce the establishment and growth of riparian plants along an environmental gradient

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Distinct population structure for co-occurring Anopheles goeldii and Anopheles triannulatus in Amazonian Brazil

To evaluate whether environmental heterogeneity contributes to the genetic heterogeneity in Anopheles triannulatus, larval habitat characteristics across the Brazilian states of Roraima and Pará and genetic sequences were examined. A comparison with Anopheles goeldii was utilised to determine whether high genetic diversity was unique to An. triannulatus. Student t test and analysis of variance found no differences in habitat characteristics between the species. Analysis of population structure of An. triannulatus and An. goeldii revealed distinct demographic histories in a largely overlapping geographic range. Cytochrome oxidase I sequence parsimony networks found geographic clustering for both species; however nuclear marker networks depicted An. triannulatus with a more complex history of fragmentation, secondary contact and recent divergence. Evidence of Pleistocene expansions suggests both species are more likely to be genetically structured by geographic and ecological barriers than demography. We hypothesise that niche partitioning is a driving force for diversity, particularly in An. triannulatus.     

Selection of High Ubiquinone 10-Producing Strain of Tobacco Cultured Cells by Cell Cloning Technique

A novel enzyme, which was named N^α-benzyloxycarbonyl amino acid urethane hydrolase, was purified from a cell-free extract of Streptococcus faecalis R ATCC 8043, using N^α-benzyloxycarbonyl glycine as substrate. The enzyme was purified 1300-fold with an activity yield of 8%. The purified enzyme was homogeneous by disc electrophoresis. The molecular weight of the native enzyme is about 220,000 by gel filtration, and a molecular weight of 32,000 was determined for the reduced and denatured enzyme by gel electrophoresis in sodium dodecyl sulfate. The isoelectric point was 4.48. The enzyme was inhibited by p-chloromercuribenzoate. The presence of divalent cations (i.e., Co²⁺ or Zn²⁺) is essential for its activity.     

Studies on Oxidation-Reduction Potentials (ORP) of Microbial Cultures

Aerobacter aerogenes No. 505 isolated from soil by Uyeda produced l-valine extracellularly by an aerobic shaking culture. Under anaerobic conditions the production of this amino acid was inhibited while lactic acid as well as a small amount of alanine were produced. The changes in ORP during the incubation under both conditions were investigated. When l-valine was the main product under aerobic conditions the ORP showed a constant value (rH 8.0) from 16 to 40 hr after inoculation. But when lactic acid was the main product and alanine was produced as the only amino acid under anaerobic conditions, the ORP drifted to rH 0 (zero). The phenomenon of the conversion of fermentation was shown clearly by the ORP of the culture broth.

The endpotentiai of lactic acid fermentation by Rhizopus G-36 was rH 13 to 14 when measured in the presence of trace amounts of redox dye mixtures. Without dyes, the rH was 18 to 22 and this fungal culture was slower in reaching endpotentials than bacterial cultures. It was postulated that the amount of redox substances exhibiting electromotive activity was not sufficient in this culture.

rH value 13 to 14 was not obtained under such conditions that lactic acid was not produced; that is in a medium with higher concentration of the nitrogen source in the presence of Fe²⁺ and Zn²⁺, or in a medium containing acetate in place of glucose as the carbon source.

Mycelia of Rhizopus G-36 after 36 hr-culture produced lactic acid even in the absence of oxygen. But unexpectedly, the ORP under anaerobic secondary culture was exactly the same as that in the aerobic shaking culture (rH 13.2).

A method for homogenization of the culture without secondary oxidation was improved. The ORP of anaerobically homogenized cultures was rH 11, and was thought to be due to the activities of all redox systems in the mycelium.

The respiration system of this strain was switched from cytochrome system to flavin system at the point of change in KGN-sensitivity. The ORP of this strain may be influenced by respiration through the flavin system.     

Studies on Oxidation-Reduction Potentials (ORP) of Microbial Cultures

At maximum production of l-glutamic acid, the oxidation-reduction potential of the culture broth in l-glutamic acid fermentation showed a stable value of 9.0 to 9.6 as rH value. When biotin concentration in the medium was high (40γ/liter), the production of l-glutamic acid decreased, and the rH was 8.0 and it was out of accordance with that of the control (biotin-poor; 2γ/liter). Under “less-aerobic” conditions, its rH rose to 10.4.

From these results, it was concluded that the rH during maximum production of l-glutamic acid showed a stable value affected actively by the redox system, l-glutamic acid/α-ketoglutaric acid and      

Bacteriophages of Clostridium saccharoperbutylacetonicum

The morphological properties of the twelve previously described HM-phages were examined by electron microscopy. Specimens were prepared by air-drying and shadow-casting method using purified phage suspensions. As a result, the HM-phages were classified into three morphologically distinct groups, 1, 11 and 111. Group 1 phages were HM 1, HM 2, HM 8, HM 9, HM 10, HM 11 and HM 12. These phages had a spherical head about 100 mμ in diameter and a rudimentary tail. Group 11 phages were HM 3, HM 4, HM 5 and HM 6. These phages had a spherical head about 100 mμ in diameter and a tail with contractile sheath, and the normal tail of these phages was about 100 mμ in length, and the contracted sheath was about 50 mμ in length, Group 111 phage was HM 7 alone. This phage had a spherical head about 120 mμ in diameter and a relatively long tail about 350 mμ in length.     

Oxytocin Increases the Influence of Public Service Advertisements

This paper presents a neurophysiologic model of effective public service advertisements (PSAs) and reports two experiments that test the model. In Experiment 1, we show that after watching 16 PSAs participants who received oxytocin, compared to those given a placebo, donated to 57% more causes, donated 56% more money, and reported 17% greater concern for those in the ads. In Experiment 2, we measured adrenocorticotropin hormone (ACTH) and oxytocin levels in blood before and after participants watched a PSA. As predicted by the model, donations occurred when participants had increases in both ACTH and oxytocin. Our results indicate that PSAs with social content that cause OT release will be more effective than those that do not. Our results also explain why some individuals do not respond to PSAs.     

Real-Time Loop-Mediated Isothermal Amplification (RealAmp) for the Species-Specific Identification of Plasmodium vivax

Plasmodium vivax infections remain a major source of malaria-related morbidity and mortality. Early and accurate diagnosis is an integral component of effective malaria control programs. Conventional molecular diagnostic methods provide accurate results but are often resource-intensive, expensive, have a long turnaround time and are beyond the capacity of most malaria-endemic countries. Our laboratory has recently developed a new platform called RealAmp, which combines loop-mediated isothermal amplification (LAMP) with a portable tube scanner real-time isothermal instrument for the rapid detection of malaria parasites. Here we describe new primers for the detection of P. vivax using the RealAmp method. Three pairs of amplification primers required for this method were derived from a conserved DNA sequence unique to the P. vivax genome. The amplification was carried out at 64°C using SYBR Green or SYTO-9 intercalating dyes for 90 minutes with the tube scanner set to collect fluorescence signals at 1-minute intervals. Clinical samples of P. vivax and other human-infecting malaria parasite species were used to determine the sensitivity and specificity of the primers by comparing with an 18S ribosomal RNA-based nested PCR as the gold standard. The new set of primers consistently detected laboratory-maintained isolates of P. vivax from different parts of the world. The primers detected P. vivax in the clinical samples with 94.59% sensitivity (95% CI: 87.48–98.26%) and 100% specificity (95% CI: 90.40–100%) compared to the gold standard nested-PCR method. The new primers also proved to be more sensitive than the published species-specific primers specifically developed for the LAMP method in detecting P. vivax.