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Gastrointestinal diseases are an important cause of morbidity and mortality worldwide. These include infectious pathologies, allergic and chronic inflammatory conditions such as Crohn´s disease ulcerative colitis and also functional disorders such as irritable bowel syndrome, for which treatment sometimes is difficult due to multiple hypotheses for these pathologies where many factors such as psychological, social, genetic, and recently, disorders of intestinal microbiota have been described. The presence of microorganisms in the intestinal tract have been described since Fiftieth century, but its was until the use of biomolecular methods that function and nature of the gastrointestinal ecosystem of microbiota were known. This was an important contribution to the knowledge of digestion, absortion, immunologic, and protective functions of the intestinal microbioma of each organism, which is essential for the study, the treatment and prevention of numerous conditions. [ABSTRACT FROM AUTHOR]

In Chile, all necrotic arachnidism is attributed to the Chilean recluse spider Loxosceles laeta ( Nicolet) ( Araneae: Sicariidae). It is predated by the spitting spider Scytodes globula ( Nicolet) ( Araneae: Scytodidae). The biology of each of these species is not well known and it is important to clarify their distributions. The aims of this study are to elucidate the variables involved in the niches of both species based on environmental and human footprint variables, and to construct geographic maps that will be useful in estimating potential distributions and in defining a map of estimated risk for loxoscelism in Chile. Loxosceles laeta was found to be associated with high temperatures and low rates of precipitation, whereas although S. globula was also associated with high temperatures, its distribution was associated with a higher level of precipitation. The main variable associated with the distribution of L. laeta was the human footprint (48.6%), which suggests that this is a highly invasive species. Similarly to other species, the distribution of L. laeta reaches its southern limit at the Los Lagos region in Chile, which coincides with high levels of precipitation and low temperatures. The potential distribution of L. laeta in Chile corresponds to the distribution of cases of loxoscelism. [ABSTRACT FROM AUTHOR]

The component Allee effect has been defined as 'a positive relationship between any measure of individual fitness and the number or density of conspecifics'. Larger plant populations or large patches have shown a higher pollinator visitation rate, which may give rise to an Allee effect in reproduction of the plants. We experimentally tested the effect of number of conspecifics on reproduction and pollinator visitation in Eschscholzia californica Cham., an invasive plant in Chile. We then built patches with two, eight and 16 flowering individuals of E. californica (11 replicates per treatment) in an area characterised by dominance of the study species. We found that E. californica exhibits a component Allee effect, as the number of individuals of this species has a positive effect on individual seed set. However, individual fruit production was not affected by the number of plants examined. Pollinator visitation rate was also independent of the number of plants, so this factor would not explain the Allee effect. This rate was positively correlated with the total number of flowers in the patches. We also found that the number of plants did not affect the seed mass or proportion of germinated seeds in the patches. Higher pollen availability in patches with 16 plants and pollination by wind could explain the Allee effect. The component Allee effect identified could lead to a weak demographic Allee effect that might reduce the rate of spread of E. californica. Knowledge of this would be useful for management of this invasive plant in Chile. [ABSTRACT FROM AUTHOR]

The effect of graphite, CeO 2 and nanohybrid CeO 2 -graphite on an Al–Mg–Si system (6063 alloys) was studied in this paper. Such alloy was reinforced using mechanical milling, followed by a conventional sintering process. Studies for structure, microstructure, and mechanical properties were carried out through X-ray diffraction, electron microscopy, and compression and Vickers microhardness testing. Results showed that the milling process enables homogeneous dispersion of the different reinforcement materials in the Al–Mg–Si matrix. The best performance, concerning reinforcement capacity and microhardness, was obtained with samples reinforced with graphite. The mechanisms involved in enhancing the mechanical properties were active and latent. The first includes grain-size refinement and strengthening by dispersion of a second phase, and the second is related to thermal mismatch. [Display omitted] • The Gr, CeO 2 , and nanohybrid CeO 2 -Gr reinforcements were homogeneously dispersed. • The reinforcements containing Gr presented the formation of Al 4 C 3 during sintering. • The CeO 2 presented a partial reduction into Ce 7 O 12 during sintering. • The reinforcements containing Gr showed the best mechanical response. • The active and latent strengthening mechanisms enhanced the mechanical properties. [ABSTRACT FROM AUTHOR]

Highlights: [•] Al7075–graphite composites were fabricated by mechanical alloying and hot extrusion. [•] Mechanical properties are enhanced as function of graphite content and milling time. [•] The strengthening is due to grain refining, Al4C3 and increased dislocation density. [ABSTRACT FROM AUTHOR]

Here we show that spontaneous oxidation of MnO nanoparticles into MnO/Mn3O4 core/shell nanoparticles has the effect of a local pressure, decreasing the MnO cell parameter and increasing strain, resulting in the increase of the MnO antiferromagnetic/paramagnetic transition temperature TN. These effects are more severe in smaller nanoparticles. [ABSTRACT FROM AUTHOR]

The ecological effect of prawn trawling on the benthos of the Gulf of Carpentaria, northern Australia, was investigated by examining stomach contents of common demersal fishes incidentally caught as by-catch in the fishery. Fishes were collected from high and low fishing intensity sites in three regions based on vessel monitoring system data. The diets of eight species of benthic fish predators were compared between regions and fishing intensities. A regional effect on diet was evident for seven species. Only one generalist species had no significant difference in diet among the three regions. For the comparisons within each region, five predator species had significantly different diet between high and low fishing intensities in at least one region. Across the three regions, high fishing intensity sites had predators that consumed a greater biomass of crustaceans, molluscs and echinoderms. At low fishing intensity sites, predators had diets comprising a greater biomass of cnidarians and teleosts, and a different assemblage of molluscs, crustaceans and fishes. These changes in diet suggest that there may have been a shift in the structure of the benthic community following intensive fishing. Analysis of predator diets is a useful tool to help identify changes in the benthic community composition after exposure to fishing. This study also provided valuable diet information on a range of abundant generalist benthic predators to improve the ecosystem modelling tools needed to support ecosystem-based fisheries management. [ABSTRACT FROM AUTHOR]

An abstract of the article "Tomato Yellow Leaf Distortion Virus, a New Bipartite Begomovirus Infecting Tomato in Cuba," by E. Fiallo-Olivé, Y. Martínez-Zubiaur and R. F. Rivera-Bustamante is presented.

Background: Although not definitively proven, there is commonly accepted to be a latitudinal gradient in the distribution of multiple sclerosis (MS), which is more frequent in temperate zones. The European Mediterranean countries are situated in a zone of median frequency, although ever increasing figures have been noted in the last decades.Objective: The objective of this study was to assess the current prevalence rate of MS in the province of Malaga, Southern Spain.Methods: The capture–recapture method (CRM) uses independent sources of data and permits the number of non-registered cases of a given disease to be estimated, and by doing so, to avoid ascertainment bias.Results: Use of this method showed the estimated prevalence rate of MS in the province of Malaga, Southern Spain, to be 125/105 (95% confidence interval: 102/105–169/105), higher than the figures published previously.Conclusions: Although we recognize that these data need to be confirmed in further studies and in other areas of the country using a similar method, we believe this study is the first to find such high figure of prevalence, being very similar to the figures reported in recent years in other southern European countries. [ABSTRACT FROM AUTHOR]

Obstructive sleep apnea is a frequent medical condition consisting in repetitive sleep-related episodes of upper airways obstruction and concurrent events of arterial blood hypoxia. There is a frequent association of cardiovascular diseases and other pathologies to this condition conforming the obstructive sleep apnea syndrome (OSAS). Laboratory models of OSAS consist in animals exposed to repetitive episodes of intermittent hypoxia (IH) which also develop cardiovascular pathologies, mostly hypertension. The overall OSAS pathophysiology appears to be linked to the repetitive hypoxia, which would cause a sensitization of carotid body (CB) chemoreflex and chemoreflex-driven hyperreactivity of the sympathetic nervous system. However, this proposal is uncertain because hyperventilation, reflecting the CB sensitization, and increased plasma CA levels, reflecting sympathetic hyperreactivity, are not constant findings in patients with OSAS and IH animals. Aiming to solve these uncertainties we have studied the entire CB chemoreflex arch in a rat model of IH, including activity of chemoreceptor cells and CB generated afferent activity to brainstem. The efferent activity was measured as ventilation in normoxia, hypoxia, and hypercapnia. Norepinephrine turnover in renal artery sympathetic endings was also assessed. Findings indicate a sensitization of the CB function to hypoxia evidenced by exaggerated chemoreceptor cell and CB afferent activity. Yet, IH rats exhibited marked hypoventilation in all studied conditions and increased turnover of norepinephrine in sympathetic endings. We conclude that IH produces a bias in the integration of the input arising from the CB with a diminished drive of ventilation and an exaggerated activation of brainstem sympathetic neurons. J. Cell. Physiol. 226: 1961-1969, 2011. © 2010 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]

Rhynchosia minima (L.) DC. (Fabaceae) plants exhibiting bright golden mosaic symptoms were previously associated with begomovirus infection in Yucatan, México []. To characterize the begomovirus infecting these plants, the complete bipartite genome was cloned and sequenced. Sequence comparisons indicated that the virus was distinct from all other begomoviruses known to date, including those previously identified from symptomatic R. minima, and the name Rhynchosia yellow mosaic Yucatan virus (RhYMYuV) is proposed. Pairwise comparisons indicated that RhYMYuV DNA-A [2,597 nt, (EU021216)] and DNA-B [2,542 nt, (FJ792608)] components shared the highest nt sequence identity with Cabbage leaf curl virus (CaLCuV), 87% for component A and 71% for component B. Phylogenetic analysis indicated that both components of RhYMYuV are most closely related to other New World begomoviruses, having as closest relatives immediate outliers to the major Squash leaf curl virus (SLCV) clade. Recombination analysis of the RhYMYuV genome indicated that the DNA-A component has arisen through intermolecular recombination. R. minima plants inoculated with the monomeric clones developed a bright yellow mosaic similar to symptoms observed in naturally infected plants, confirming that the clones were infectious. Nicotiana benthamiana plants biolistically inoculated with monomeric clones developed curling and chlorosis in the newly emerging leaves. RhYMYuV was also detected in symptomatic Desmodium sect. Scorpiurus Benth. (Fabaceae) that were collected near the RhYMYuV-infected plants. [ABSTRACT FROM AUTHOR]

The article focuses on the use of genetic identification (ID) to detect positive blind samples and prove that polymerase chain reaction (PCR) is a reliable method in determining specific DNA sequences in Mexican landrace maize. It notes that the PCR amplification of transgenic sequences in maize backgrounds tend to produce relatively faint bands of variable intensity but this should be considered due to various reasons, including the gradual activation of Taq polymerase. Accordingly, the sequence diversity among the events of the detected transgenic transformation was confirmed by the sequencing data provided by the researchers. Furthermore, an enzyme-linked immunosorbent assay (ELISA) targeted at detecting recombinant proteins in maize shows that transgenes are present in the maize.

The rolling circle amplification (RCA) has been an effective and quick alternative to study the biological diversity of geminiviruses in different regions of the world. This technology allows obtaining the amplification of small circular DNA and of simple strand, without taking into account the possible sequential variations. In addition, the RCA has a high copy fidelity and the quantity of DNA template is extremely low. In Cuba, extensive areas dedicated to grow vegetables, potato, beans and tobacco are affected by different begomovirus species, with such a wide diversity that hinders to have appropriate generic primers to study this viral genus. In works of national prospecting, tomato, tobacco and pepper plants with symptoms associated with begomoviruses were collected. DNA was extracted and amplified by rolling circle with the objective of obtaining copies of the entire viral genome. As a result, the presence of two new bipartite begomoviruses was observed and proposed as new species. They were named Tomato yellow leaf distortion virus, found in tomato crops, and Tobacco yellow crinkle virus infecting tobacco and pepper. The results obtained confirm how useful the RCA is to study the diversity of begomoviruses and their interactions in the productive agroecosystems. [ABSTRACT FROM AUTHOR]

A possible consequence of planting genetically modified organisms (GMOs) in centres of crop origin is unintended gene flow into traditional landraces. In 2001, a study reported the presence of the transgenic 35S promoter in maize landraces sampled in 2000 from the Sierra Juarez of Oaxaca, Mexico. Analysis of a large sample taken from the same region in 2003 and 2004 could not confirm the existence of transgenes, thereby casting doubt on the earlier results. These two studies were based on different sampling and analytical procedures and are thus hard to compare. Here, we present new molecular data for this region that confirm the presence of transgenes in three of 23 localities sampled in 2001. Transgene sequences were not detected in samples taken in 2002 from nine localities, while directed samples taken in 2004 from two of the positive 2001 localities were again found to contain transgenic sequences. These findings suggest the persistence or re-introduction of transgenes up until 2004 in this area. We address variability in recombinant sequence detection by analyzing the consistency of current molecular assays. We also present theoretical results on the limitations of estimating the probability of transgene detection in samples taken from landraces. The inclusion of a limited number of female gametes and, more importantly, aggregated transgene distributions may significantly lower detection probabilities. Our analytical and sampling considerations help explain discrepancies among different detection efforts, including the one presented here, and provide considerations for the establishment of monitoring protocols to detect the presence of transgenes among structured populations of landraces. [ABSTRACT FROM AUTHOR]

Background: Systemic inflammatory response frequently occurs after coronary artery bypass surgery and is strongly correlated with the risk of postoperative morbidity and mortality. This study tests the hypothesis that the priming of the extracorporeal circuit with colloid solutions results in less inflammation in patients undergoing cardiac surgery than priming with crystalloid solutions. Methods: A prospective, randomized study was designed. Forty-four patients undergoing elective coronary artery bypass grafting were randomly allocated to one of two groups: 22 patients primed with Ringer's lactate (RL) solution and 22 patients primed with gelatin-containing solution during the surgery. Plasma levels of interleukin (IL)-6, IL-8, tumor necrosis factor (TNF)-α, C-reactive protein (CRP) and, complement 4 were measured during the surgical intervention and over the following 48 postoperative hours. Cytokine levels were measured by enzyme-linked assays from plasma samples obtained at specific time points pre- and post-operatively. Results: In both groups the serum levels of the pro-inflammatory cytokines (IL-6, IL-8, TNF-α), CRP, complement 4, and leukocytes increased significantly over the baseline, although no significant differences were observed between the two groups. The operation time, blood loss, need for inotropic support, extubation time, and length of intensive care unit stay did not differ significantly between the two groups. Conclusion: Priming with gelatin vs. RL produces no significant differences in the inflammatory response in patients undergoing coronary artery bypass grafting with cardiopulmonary bypass. [ABSTRACT FROM AUTHOR]

We evaluated the effects of marine iguanas, sally lightfoot crabs, and fish on rocky-shore sessile organisms at two sites at Santa Cruz Island, Galápagos Islands, Ecuador, for 3–5 years during and after the 1997–1998 El Niño, using exclusion cages to separate the effects. Plots exposed to natural grazing were dominated either by encrusting algae or by red algal turf and articulated corallines. Algae fluctuated in response to El Niño in the following way. During an early phase, crustose Gymnogongrus and/or red algal turf were dominant. In the heart of El Niño, grazers had limited effects on algal cover but influenced algal sizes substantially. Most algae (particularly edible forms) were scarce or declined, although warm-water ephemeral species (notably Giffordia mitchelliae) flourished, increasing diversity and overgrowing crusts. Iguana mortalities were high, and crab densities low. When normal conditions returned, warm-water ephemerals declined, crab densities rose, and grazers had significant but site-specific effects on algae. At one site, any combination of grazers diminished most erect species, reducing diversity and restoring dominance of competitively inferior grazer-resistant crusts. At a second site, only the combined effect of all grazers had this effect. Laboratory experiments confirmed that crabs could control erect algae and promote crustose forms, and crustose Gymnogongrus developed into an erect form in the absence of crabs. Differences between sites and large-scale temporal changes associated with El Niño indicate that tropical shores are not all as constant in time and space as previously suggested. Mobile grazers did affect algal communities, but over the period of our observations far greater effects were attributable to intersite differences and temporal shifts in oceanographic conditions. El Niño events reduce nutrients, intensify wave action, and raise sea levels, affecting food availability for ihtertidal herbivores and their influence on benthic algae. Thus, the dramatic transformations of communities during El Niño presage the impacts of global climate change. [ABSTRACT FROM AUTHOR]

Abstract: Introduction: Serum creatinine (sCr) is the most commonly used biochemical parameter for gauging kidney function, but, due to its limitations, it is not the ideal marker for glomerular filtration rate (GFR). Cystatin C (sCyC) appears to be an endogenous marker of GFR. Aim: To assess the use of sCyC as a marker of renal function in kidney transplant patients, we compared it with sCr and with creatinine clearance either in a 24-hour urine or calculated using the Cockroft-Gault formula. Methods: Among 78 patients (62.8% men, 37.2% women) undergoing kidney transplantation (average age 44.87 ± 13.37 years) we determined at 2, 5, 7, 15, and 30 days, and 6, 12 and 18 months after kidney transplantation: sCr (using the Jaffé colorimetric method), sCyC (immunonephelometry), creatinine clearance with a 24-hour urine, creatinine clearance using the Cockroft-Gault formula. Results: During the first 30 days following transplantation, there was a progressive decline in sCr levels. sCyC increased up to the fifth day, coinciding with the highest doses of steroids, and then decreased. At 6, 12, and 18 months, there was a correlation between sCyC and sCr, creatinine clearance in a 24-hour urine or calculated with the Cockroft-Gault formula (R = 0.859; R = −0.713, and R = −0.684, respectively, P < .001.) Conclusions: sCyC is an endogenous marker of GFR. Its limitations relate to its being affected by the high doses of steroids in the first days following transplantation. In the 18-month posttransplant period, it correlated with creatinine clearance in a 24-hour urine or calculated by the Cockroft-Gault formula. [Copyright &y& Elsevier]

Abstract: The present work shows that the 5-amino-1,10-phenanthroline (5Aphen) molecule can be electrochemically polymerised, forming a conducting polymer, through potentiodynamic as well as potentiostatic methods onto different electrode substrates: (1) A composite formed by carbon paste in an epoxy matrix, (2) glassy carbon and (3) polycrystalline gold. From the analysis of the experimental potentiostatic current-time plots obtained using electrodes (2) and (3) it is shown that for both cases the formation mechanism of the polymer, (poly5Aphen) involves the simultaneous presence of an adsorption process, which seems predominant at times short enough to the start of the potential jump, and a three-dimensional, 3D, nucleation and growth process limited by the monomer diffusion toward the electrode''s interphase. The mechanism suggests that the growth of the polymer takes place via direct incorporation of the monomer species. Studies carried out varying the angular speed of the vitreous carbon rotating disc electrode (RDE) showed that the limiting current increased directly proportional to the square root of the rotation frequency, as predicted by the Levich equation, thus indicating that the possible formation of intermediate oligomer species have a small effect on the polymer growth. A theoretical study of the monomer and some oligomers, through evaluation of the Fukui functions, allowed us to gain insight on the mechanism of polymerization of 5Aphen. It was found a linear oligomer species that adequately describe the experimental features found like the conducting nature of the polymer formed. [Copyright &y& Elsevier]

Analyzes the gene expression by Pepper huasteco virus (PHV) in Capsicum chinense plants with resistance to geminivirus infections. Use of differential display reverse transcription polymerase chain reaction; Role of the genes in the interaction between pepper and PHV; Evaluation of the virus-free state of the plants; Cloning and sequencing DNA fragments; Virus inoculation.

Hypoxia increases the release of neurotransmitters from chemoreceptor cells of the carotid body (CB) and the activity in the carotid sinus nerve (CSN) sensory fibers, elevating ventilatory drive. According to previous reports, perinatal hyperoxia causes CSN hypotrophy and varied diminishment of CB function and the hypoxic ventilatory response. The present study aimed to characterize the presumptive hyperoxic damage. Hyperoxic rats were born and reared for 28 days in 55%-60% O2; subsequent growth (to 3.5-4.5 months) was in a normal atmosphere. Hyperoxic and control rats (born and reared in a normal atmosphere) responded with a similar increase in ventilatory frequency to hypoxia and hypercapnia. In comparison with the controls, hyperoxic CBs showed (1) half the size, but comparable percentage area positive to tyrosine hydroxylase (chemoreceptor cells) in histological sections; (2) a twofold increase in dopamine (DA) concentration, but a 50% reduction in DA synthesis rate; (3) a 75% reduction in hypoxia-evoked DA release, but normal high [K+] 0-evoked release; (4) a 75% reduction in the number of hypoxia-sensitive CSN fibers (although responding units displayed a nearly normal hypoxic response); and (5) a smaller percentage of chemoreceptor cells that increased [Ca2+]1 in hypoxia, although responses were within the normal range. We conclude that perinatal hyperoxia causes atrophy of the CB-CSN complex, resulting in a smaller number of chemoreceptor cells and fibers. Additionally, hyperoxia damages O2-sensing, but not exocytotic, machinery in most surviving chemoreceptor cells. Although hyperoxic CBs contain substantially smaller numbers of chemoreceptor cells/sensory fibers responsive to hypoxia they appear sufficient to evoke normal increases in ventilatory frequency. [ABSTRACT FROM AUTHOR]

Summary. Over the last decade, the tomato production in Cuba has been affected by new whitefly-associated diseases. In addition to the well-documented presence of Tomato yellow leaf curl virus (TYLCV) along the island, the occurrence of bipartite begomoviruses has also been reported. One of them, tentatively named Tomato mottle Taino virus (ToMoTV), has now been cloned and characterized at the molecular level. Its genomic organization is similar to other bipartite geminiviruses. Phylogenetic analyses placed ToMoTV in a subcluster with other geminiviruses isolated in the Caribbean Basin: Tomato mottle virus (ToMoV), Bean dwarf mosaic virus, Abutilon mosaic virus, Sida golden mosaic virus and Potato yellow mosaic virus (PYMV). Biolistic inoculation of tobacco and tomato plants with cloned viral DNA showed that ToMoTV pseudorecombines with PYMV-GP as predicted by the identity of their iterative elements, whereas it does not show the same ability with ToMoV, even when their replication-associated proteins (Rep and REn) show the highest percentage of similarity. A comparative analysis of Rep proteins from begomoviruses that are able to produce viable reassortants suggests that some key elements for virus replication specificity are located in the first ten amino acids of this protein. [ABSTRACT FROM AUTHOR]

Background. Recent reports about cisapride have raised some concerns about the safety and efficacy of this medication in children. The aim of this study was to identify electrocardiographic changes and a predisposition to develop arrhythmias in children.Methods. Patients were divided in 2 groups: 1) 63 children (mean age: 29 months) who received cisapride (0.2 mg/kg/dose 3 times/day), and 2) 57 children (mean age: 27 months) who did not receive cisapride (they served as controls). Both groups did not have any associated disease. Electrocardiogram (EKG) was performed to children when they were included in the study. The QT interval was corrected using Bazett's formula. Twenty-four-hour Holter recording was performed in children with prolonged QT interval (PQTI). When PQTI was identified in group 1, cisapride was discontinued and a new EKG was performed.Results. Five children from group 1 and 6 from group 2 had PQTI. In 3 children with PQTI, the QTc interval returned to normal values when cisapride was discontinued. In children under 4 months of age, a statistical difference was found, with QTc interval being longer in group 2 (without cisapride) than in group 1. Holter recordings were normal in all children with PQTI.Conclusion. PQTI can be found in normal children with or without cisapride. In our study PQTI was not associated with any life-threatening event. [ABSTRACT FROM AUTHOR]