An assessment of the AFLP method for investigating population structure in the red alga Chondrus crispus Stackhouse (Gigartinales, Florideophyceae)

The appropriateness of the Amplified Fragment Length Polymorphism (AFLP) technique for investigating Chondrus crispus Stackhouse populations in the Maritime Provinces of Canada was assessed. The AFLP procedure was first subjected to reproducibility testing and three shortcomings were noted: 1) failure to reproduce band intensity between replicate runs for the same individual and primer pair; 2) failure of some bands to replicate; 3) lack of reproducibility for complete replicate runs for some individuals and primer pairs. In the last-mentioned case, the lack of reproducibility resulted in characteristic electropherograms indicative of weak reactions. These weak runs can be attributed to poor restriction digest/ligation reactions and/or substandard PCR, these failures ultimately resulting from low and inconsistent DNA quality. We recommend that reproducibility testing should be completed routinely in studies using the AFLP technique. In the current work, only fragments and individuals that gave reproducible results were used in subsequent analyses. The AFLP method resulted in highly variable markers within and between the populations of C. crispus included in this investigation, which prevented successful resolution of population structure. This situation could result from a lack of suitability for AFLP markers in population genetic studies, and/or too extensive genetic variation for C. crispus populations to be discerned by the AFLP technique. These two possible explanations are discussed. This revised version was published online in August 2006 with corrections to the Cover Date.     

Microsatellites for the Neotropical ant,Camponotus leydigi (Hymenoptera: Formicidae)

Ants (Hymenoptera: Formicidae) are dominant social insects that play important ecological roles in terrestrial ecosystems. Camponotus leydigi (Forel) is widely distributed in the Neotropical region and is frequently found in the Brazilian cerrado savanna interacting with plants and other insects. Field observations indicate that C. leydigi has a polydomous nesting habit, but little is known about the genetic relationship among workers. In this study, we identify the first nine microsatellite loci for C. leydigi that will allow further investigation on its genetic diversity. We used a microsatellite-enriched library method. According to this method, repetitive sequences are captured with (CT)₈ and (GT)₈ biotin-linked probes, with subsequent recovery by streptavidin magnetic-coated beads. We observed that eight loci were polymorphic. The mean (± standard error) observed and expected heterozygosities were 0.55 ± 0.23 and 0.73 ± 0.28, respectively. The rarified allelic richness ranged from 1 to 5.32. The polymorphism contents were similar to diversity estimates found in markers previously developed for other Camponotus ants. These markers will be useful for future studies on population genetics and ecology of Camponotus ants in cerrado, including nesting ecology, colony structure, dispersal and conservation.     

Cross-amplification of nonnative Acacia species in the Hawaiian Islands using microsatellite markers from Acacia koa

Thirty-one microsatellite markers, developed from Acacia koa, were evaluated for cross-amplification of seven nonnative species of Acacia in the Hawaiian Islands. The number of alleles per locus ranged from one to seven, with 16 of the 31 markers showing polymorphism in at least two of the nonnative Acacia species. Of the Acacia species examined, A. melanoxylon showed the highest percentage of amplified loci.     

A review of potential techniques for identifying individual stoats (Mustela erminea) visiting control or monitoring stations

Abstract

We review ways of individually identifying stoats (Mustela erminea) and similar small mammals from visits to bait stations or to monitoring devices in the field. Tracking devices are the cheapest and most practical method currently available of measuring the presence of a particular species, but there has been little research on the recognition of individuals. Elongation of tracking tunnels, or using sooty plates rather than ink to record prints, may improve detectability of individual markings. Recording visits to bait stations or tracking tunnels from DNA sequencing of hair or skin samples is likely to be prohibitively expensive for many monitoring programmes. Identification of stoats visiting bait stations or tracking tunnels using electronic devices has great potential, but these techniques are impracticably expensive because stoats move over such large areas that individual receivers and data loggers would be needed for each bait station. Chemical bait markers such as rhodamine B may be the most suitable method for identifying which animals have used a particular bait station.     

Should biochemical markers of bone turnover be considered standard practice for safety pharmacology?

The success in biomedical sciences such as genomics and proteomics is not paralleled in the medical product development methods. The consequence of this is a lack of translation into improved drug safety and efficacy. Therefore the US Food and Drug Administration (FDA) introduced the Critical Path Initiative in 2004 to modernize drug development and safety pharmacology. Bone is that largest tissue by weight, and is continuously remodelled. Changes in bone turnover lead to complications such as osteoporosis and fracture, that is associated with an increased mortality. Recent findings have identified bone as a possible endocrine organ and the availability of valid biochemical bone markers suggests that assessing bone turnover should also play an important role in general safety pharmacology.     

Diazepam ameliorates altered proinflammatory and cardiac markers in stress exposed rats

Regular exposure to stress causes alteration in biochemical parameter but till date no specific medicine prescribed for controlling it. Current study aimed to determine the effect of Diazepam on proinflammatory and cardiac markers in stress exposed rats. Male Wistar rats were divided into four groups with six animals in each group for 90 days study. Group-1 served as a Normal Control (NC), Groups-2, as a Disease Control (DC), Group-3 as a Diazepam Control (DMC) and Group-4 as a Disease + Diazepam Treatment (DT). DMC and DT animals exposed to regular stress by forced swimming exercise method for 90 days. DMC and DT received 5 mg/kg, p.o the daily dose of Diazepam. At the end of the protocol, animals were sacrificed. The level of serum proinflammatory marker interleukin-6 in DC increased significantly (p < 0.001) while restored significantly (p < 0.001) in DT. Level of interleukin-10 in DC decreased significantly (p < 0.001) while restored significantly (p < 0.001) in DT. Level of fibrinogen was also increased by stress, which was restored significantly (p < 0.05) by diazepam. Increased level of Creatine kinase-MB (CK-MB) by stress was restored significantly (p < 0.05) by diazepam. The level of cortisol was increased also significantly (p < 0.001) and restored to normal by diazepam. The level of C-reactive protein (CRP) and cholesterol was increased significantly (p < 0.01; p < 0.001) by stress while restored significantly (p < 0.01; p < 0.001) by diazepam. Findings from results suggest that diazepam ameliorates altered proinflammatory and cardiac markers in stress exposed rats.     

THE EFFECT OF AEROBIC TRAINING ON SERUM ADIPONECTIN AND LEPTIN LEVELS AND INFLAMMATORY MARKERS OF CORONARY HEART DISEASE IN OBESE MEN

The aim of this study was to investigate the effect of 12 weeks of aerobic training on the serum levels of adiponectin and leptin and on inflammatory markers of coronary heart disease in obese men. Sixteen non-athlete obese men were randomly assigned to one of two experimental groups. The experimental group underwent aerobic training consisting of three sessions per week for 12 weeks, while the control group did not participate in the training programme during the study period. Five millilitres of venous blood was taken from each participant at the beginning of the study, during week six and at the end of week 12 to measure the levels of leptin, adiponectin, C-reactive protein, interleukin-6 and tumour necrosis factor-α. The findings showed that aerobic training led to decreases in the levels of CRP (P = 0.002), IL-6 (P = 0.001) and leptin (P = 0.003) and an increase in the level of adiponectin (P = 0.002) in the experimental group relative to the control group. In addition, the level of TNF-α decreased in the experimental group after the 12-week aerobic training period, although this change was not statistically significant. According to the results of this study, regular aerobic exercise decreases the potential risk of coronary heart disease by improving the plasma levels of IL-6, adiponectin, leptin and CRP. Additionally, aerobic exercise can be used as effective non-pharmacological treatment to prevent diseases.     

High-resolution crystal structures of transient intermediates in the phytochrome photocycle

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Genetic diversity of two endemic and endangered Plantago species

Plantago algarbiensis and Plantago almogravensis are two endangered and endemic species from Portugal. Due to the rarity and endangered nature of these species as well as the lack of molecular data, their genetic variation was evaluated using ISSR and RAPD markers. P. algarbiensis species showed higher genetic variability (73.9% of polymorphism) than P. almogravensis (61.2%). The two species revealed a high level of genetic diversity, with a Nei's genetic diversity of 0.1965 and 0.2309 and a Shannon's diversity index of 0.2975 and 0.3520, for P. almogravensis and P. algarbiensis, respectively. A low level of genetic differentiation was observed (Gst = 0.1873) among the species. However, the cluster and PCA analyses, based on genetic similarity, revealed two main, clearly separate clusters, which directly corresponded to the plants isolated from each species. In situ and ex situ measures should be applied in order to preserve both species but, based on these results, P. almogravensis population should be a priority for conservation.