Association of Vibrio cholerae O1 El Tor and O139 Bengal with the Copepods Acartia tonsa and Eurytemora affinis

The association of Vibrio cholerae with zooplankton has been suggested as an important factor in transmission of human epidemic cholera, and the ability to colonize zooplankton surfaces may play a role in the temporal variation and predominance of the two different serogroups (V. cholerae O1 El Tor and O139) in the aquatic environment. To date, interactions between specific serogroups and species of plankton remain poorly understood. Laboratory microcosm experiments were carried out to compare quantitatively the colonization of two copepod species, Acartia tonsa and Eurytemora affinis, by each of the epidemic serogroups. V. cholerae O1 consistently achieved higher abundances than V. cholerae O139 in colonizing adults of each copepod species as well as the multiple life stages of E. affinis. This difference in colonization may be significant in the general predominance of V. cholerae O1 in cholera epidemics in rural Bangladesh where water supplies are taken directly from the environment.     

The geological record of a mid-Holocene marine storm in southwestern Spain

Integrated analysis of a 50-m long sedimentary core collected in the central part of the Odiel estuary (SW Atlantic coast of Spain) allows delineation of the main paleoenvironmental changes that occurred in this area during the Holocene. Eight sedimentary facies were deposited in the last ca. 9000 years BP, confirming a transgressive-regressive cycle that involves the transition from fluvial to salt marsh deposits with intermediate marine tidal deposits. A storm event is detected at ca. 5705 ¹⁴C years BP (mean calibrated age) with distinct lithostratigraphical, textural, geochemical, and palaeontological features.     

The use of Tn5 transposable elements in a gene trapping strategy for the protozoan Leishmania

The use of transposable elements as a gene-trapping strategy is a powerful tool for gene discovery. Herein we describe the development of a transposable system, based on the bacterial Tn5 transposon, which has been used successfully in Leishmania braziliensis. The transposon carries the neomycin phosphotransferase gene, which is expressed only when inserted in-frame with a Leishmania gene present in the target DNA. Four cosmid clones from a L. braziliensis genomic library were used as targets in transposition reactions and four insertional libraries were constructed and transfected in L. braziliensis. Clones resistant to G418 were selected and analysed by immunofluorescence in order to identify the subcellular localisation of the protein coded by the trapped gene. A definitive subcellular localisation for neomycin phosphotransferase/targeted protein fusion was not obtained in any of the four Leishmania clones investigated. However, the constructed transposable element is highly efficient considering the frequency of insertion in large targets and is therefore a useful tool for functional genetic studies in Leishmania. Our data confirm the utility of the Tn5 transposon system for insertion of sequencing priming sites into target DNA. Furthermore, the high frequency of insertion and even distribution are important in studying genomic regions bearing long and polymorphic repetitive sequences.     

Structure-activity relationships, and drug metabolism and pharmacokinetic properties for indazole piperazine and indazole piperidine inhibitors of ROCK-II

ROCK has been implicated in many diseases ranging from glaucoma to spinal cord injury and is therefore an important target for therapeutic intervention. In this study, we have designed a series of 1-(4-(1H-indazol-5-yl)piperazin-1-yl)-2-hydroxy(or 2-amino) analogs and a series of 1-(4-(1H-indazol-5-yl amino)piperidin-1-yl)-2-hydroxy(or 2-amino) inhibitors of ROCK-II. SR-1459 has IC(50)=13nM versus ROCK-II while the IC(50)s for SR-715 and SR-899 are 80nM and 100nM, respectively. Many of these inhibitors, especially the 2-amino substituted analogs for both series, are modest/potent CYP3A4 inhibitors as well. However, a few of these inhibitors (SR-715 and SR-899) show strong selectivity for ROCK-II over CYP3A4, but the overall potency of the 2-amino analogs (SR-1459) on CYP3A4 and the high clearance and volume of distribution of these compounds makes the in vivo utility of these analogs undesirable.     

Exploring the origin of egg protein in an oviparous water snake (Natrix maura)

Reptiles are typical capital breeders that fuel reproduction by the use of lipids stored in fat bodies. However, little is known about the origin (exogenous or endogenous) of egg protein. We have examined the origin of egg protein by means of the analysis of protein content of liver and carcass (skeletal muscle) of the oviparous snake Natrix maura throughout an annual cycle. We have also measured monthly variation of the digestive-content mass and the ovarian mass. Results showed that protein in liver peaked during vitellogenesis according to the role of the liver in the synthesis of vitellogenin. Partial correlations showed the path of protein from the prey (digestive-content) to the liver, and finally to the ovaries, as well as an inverse relation between carcass protein and ovarian mass. Carcass muscle is the only body part that may act as a potential reserve for endogenous protein, although we did not find significant variation in carcass protein during female reproduction. As females with large follicles did not stop foraging activity, we assumed that egg protein was derived from the diet as partial correlations indicated. Our results suggest that N. maura is a capital breeder for lipids and tend to be income breeder for protein. This conclusion contrasts with that observed in capital breeders for which egg protein was derived from muscle. We discuss the idea that flexibility in the origin of egg protein could affect the body condition in post-reproductive females.     

Physiological and anthropometric characteristics of young soccer players according to their playing position: relevance for the selection process

The aim of this study was to establish the anthropometric and physiological profiles of young nonelite soccer players according to their playing position, and to determine their relevance for the selection process. Two hundred forty-one male soccer players who were members of the Getxo Arenas Club (Bizkaia) participated in this study. Players, age 17.31 (+/- 2.64) years, range 14-21 years, were classified into the following groups: forwards (n = 56), midfielders (n = 79), defenders (n = 77), and goalkeepers (n = 29). Anthropometric variables of participants (height, weight, body mass index, 6 skinfolds, 4 diameters, and 3 perimeters) were measured. Also, their somatotype and body composition (weights and percentages of fat, bone, and muscle) were calculated. Participants performed the Astrand test to estimate their absolute and relative VO2max, an endurance test, sprint tests (30 meters flat and 30 meters with 10 cones) and 3 jump tests (squat jump, counter movement jump and drop jump). Forwards were the leanest, presenting the highest percentage of muscle. They were the best performers in all the physiological tests, including endurance, velocity, agility, and power. In contrast, goalkeepers were found to be the tallest and the heaviest players. They also had the largest fat skinfolds and the highest fat percentage, but their aerobic capacity was the lowest. In the selection process, agility and the jump tests were the most discriminating for forwards. In contrast, agility, height, and endurance were the key factors for midfielders. The defenders group was characterized by a lower quantity of fat. Thus, we may conclude that anthropometric and physiological differences exist among soccer players who play in different positions. These differences fit with their different workload in a game. Therefore, training programs should include specific sessions for each positional role.     

Effect of organic solvents on the activity and stability of an extracellular protease secreted by the haloalkaliphilic archaeon <Emphasis Type="Italic">Natrialba magadii</Emphasis>

The effect of various organic solvents on the activity and stability of an extracellular protease produced by the haloalkaliphilic archaeon Natrialba magadii was tested. This protease was active and stable in aqueous-organic solvent mixtures containing 1.5 M NaCl and glycerol, dimethylsulfoxide (DMSO), N,N-dimethyl formamide, propylenglycol, and dioxane. Among the solvents tested, DMSO, propylenglycol, and glycerol were effective in preserving enzyme stability in suboptimal NaCl concentrations. The stabilizing effect of DMSO on this haloalkaliphilic protease was more efficient at pH 8 than at pH 10, suggesting that DMSO may not substitute for salt to allow halophilic proteins to withstand the effect of high pH values. These results show that Nab. magadii extracellular protease is a solvent tolerant enzyme and suggest a potential application of this haloalkaliphilic protease in aqueous-organic solvent biocatalysis.     

Cell envelope changes in Bifidobacterium animalis ssp. lactis as a response to bile

Bifidobacterium animalis ssp. lactis is a probiotic frequently used as adjunct culture in fermented dairy products. In order to ensure its proper function at the intestinal level, this bacterium has to be tolerant to physiological concentrations of bile. This study examined the influence of bile on the fatty acid composition and the membrane characteristics of B. animalis IPLA 4549 and its mutant with acquired resistance to bile, B. animalis 4549dOx. Bile adaptation triggers in B. animalis 4549dOx a decrease in membrane fluidity and in the protein : phospholipid ratio, as well as a shift in the fatty acid composition of the cell. Remarkably, the presence of bile in the growth medium induced similar changes in both B. animalis cells. Furthermore, transmission electron microscopy analysis showed that bile promotes a severe distortion of the cell surface. This study provides new insights of the action of bile on the cell envelope of bifidobacteria.     

Predictability of coral bleaching from synoptic satellite and in situ temperature observations

Satellite and compiled in situ observations of sea surface temperatures have greatly increased the ability to detect anomalous and persistent warm water and are being widely used to predict climate change, coral bleaching and mortality. A field-based synoptic view of coral bleaching spanning eight countries and ∼35° of latitude in the western Indian Ocean tested the accuracy of synoptic temperature data derived from satellites and shipboard data to detect and predict bleaching during 2005. The ability to predict the degree of bleaching based on degree heating weeks data was moderate, but increased when past temperature anomalies and coral community susceptibility were included. It is estimated that slightly more than half of the bleaching response is due to anomalous warm water and nearly half due to taxa and community level acclimation or adaptation, where these two factors have opposing effects. Cumulative temperature anomalies do identify general areas with bleaching but both large over and underestimates of bleaching intensity were observed. Consequently, field observations are needed to confirm the synoptic satellite predictions for particular reefs, particularly where acclimation and reorganization of the coral community have occurred due to past bleaching events.