Chromosome counts in Clibadium (Compositae,Heliantheae) from Latin America

New meiotic chromosome counts are reported from 86 populations from Mexico to Ecuador of 13 species ofClibadium (Compositae, Heliantheae). These, plus previous reports, yield a total of 120 counts from 20 of the approximately 39 species recognized in the genus (Arriagada, in prep.). All counts aren=16 with a few fragments or B-chromosomes observed sporadically in some populations. One population, containing what appear morphologically to be interspecific hybrids betweenC. mexiae andC. microcephalum, showed one tetravalent and fragments. Species in both historical sections (Clibadium andTrixidium, created by Candolle and maintained by Schulz) and from the five sections to be proposed in a new classification of the genus (Arriagada, in prep.) have now been counted. The uniformity of chromosome numbers withinClibadium is correlated with observed allopatric distribution of closely related taxa.     

Morin Flavonoid Adsorbed on Mesoporous Silica,a Novel Antioxidant Nanomaterial

Morin (2´,3, 4´,5,7-pentahydroxyflavone) is a flavonoid with several beneficial health effects. However, its poor water solubility and it sensitivity to several environmental factors avoid its use in applications like pharmaceutical and cosmetic. In this work, we synthetized morin-modified mesoporous silica nanoparticles (AMSNPs-MOR) as useful material to be used as potential nanoantioxidant. To achieve this, we characterized its adsorption kinetics, isotherm and the antioxidant capacity as hydroxyl radical (HO•) scavenger and singlet oxygen (¹O₂) quencher. The experimental data could be well fitted with Langmuir, Freundlich and Temkin isotherm models, besides the pseudo-second order kinetics model. The total quenching rate constant obtained for singlet oxygen deactivation by AMSNPs-MOR was one order of magnitude lower than the morin rate constant reported previously in neat solvents and lipid membranes. The AMSNPs-MOR have good antioxidant properties by itself and exhibit a synergic effect with morin on the antioxidant property against hydroxyl radical. This effect, in the range of concentrations studied, was increased when the amount of morin adsorbed increased.     

Synergistic interactions between a saprophytic fungal consortium and Rhizophagus irregularis alleviate oxidative stress in plants grown in heavy metal contaminated soil

Plant and Soil - Accumulation of heavy metals in soil causes loss of cover vegetation and increases the production of reactive oxygen species (ROS). ROS accumulation induces the expression of genes...     

Distinct Biochemical Pools of Golgi Phosphoprotein 3 in the Human Breast Cancer Cell Lines MCF7 and MDA-MB-231

Golgi phosphoprotein 3 (GOLPH3) has been implicated in the development of carcinomas in many human tissues, and is currently considered a bona fide oncoprotein. Importantly, several tumor types show overexpression of GOLPH3, which is associated with tumor progress and poor prognosis. However, the underlying molecular mechanisms that connect GOLPH3 function with tumorigenicity are poorly understood. Experimental evidence shows that depletion of GOLPH3 abolishes transformation and proliferation of tumor cells in GOLPH3-overexpressing cell lines. Conversely, GOLPH3 overexpression drives transformation of primary cell lines and enhances mouse xenograft tumor growth in vivo. This evidence suggests that overexpression of GOLPH3 could result in distinct features of GOLPH3 in tumor cells compared to that of non-tumorigenic cells. GOLPH3 is a peripheral membrane protein mostly localized at the trans-Golgi network, and its association with Golgi membranes depends on binding to phosphatidylinositol-4-phosphate. GOLPH3 is also contained in a large cytosolic pool that rapidly exchanges with Golgi-associated pools. GOLPH3 has also been observed associated with vesicles and tubules arising from the Golgi, as well as other cellular compartments, and hence it has been implicated in several membrane trafficking events. Whether these and other features are typical to all different types of cells is unknown. Moreover, it remains undetermined how GOLPH3 acts as an oncoprotein at the Golgi. Therefore, to better understand the roles of GOLPH3 in cancer cells, we sought to compare some of its biochemical and cellular properties in the human breast cancer cell lines MCF7 and MDA-MB-231 with that of the non-tumorigenic breast human cell line MCF 10A. We found unexpected differences that support the notion that in different cancer cells, overexpression of GOLPH3 functions in diverse fashions, which may influence specific tumorigenic phenotypes.     

Influences of thermal environment on fish growth

Thermoregulation in ectothermic animals is influenced by the ability to effectively respond to thermal variations. While it is known that ectotherms are affected by thermal changes, it remains unknown whether physiological and/or metabolic traits are impacted by modifications to the thermal environment. Our research provides key evidence that fish ectotherms are highly influenced by thermal variability during development, which leads to important modifications at several metabolic levels (e.g., growth trajectories, microstructural alterations, muscle injuries, and molecular mechanisms). In Atlantic salmon (Salmo salar), a wide thermal range (Δ_T 6.4°C) during development (posthatch larvae to juveniles) was associated with increases in key thermal performance measures for survival and growth trajectory. Other metabolic traits were also significantly influenced, such as size, muscle cellularity, and molecular growth regulators possibly affected by adaptive processes. In contrast, a restricted thermal range (Δ_T 1.4°C) was detrimental to growth, survival, and cellular microstructure as muscle growth could not keep pace with increased metabolic demands. These findings provide a possible basic explanation for the effects of thermal environment during growth. In conclusion, our results highlight the key role of thermal range amplitude on survival and on interactions with major metabolism‐regulating processes that have positive adaptive effects for organisms.     

Parvovirus-Derived Endogenous Viral Elements in Two South American Rodent Genomes

We describe endogenous viral elements (EVEs) derived from parvoviruses (family Parvoviridae) in the genomes of the long-tailed chinchilla (Chinchilla lanigera) and the degu (Octodon degus). The novel EVEs include dependovirus-related elements and representatives of a clearly distinct parvovirus lineage that also has endogenous representatives in marsupial genomes. In the degu, one dependovirus-derived EVE was found to carry an intact reading frame and was differentially expressed in vivo, with increased expression in the liver.     

Relación entre el rendimiento en la prueba de estación unipodal y la velocidad del centro de presión en adultos mayores

Introduction

Frequent falls are one of the most important health problems in the elderly population. The unipedal stance test (UPST), asses postural stability and is used in fall risk measures. Despite this, there is little information about its relationship with posturographic parameters (PP) that characterizes postural stability. Center of pressure velocity (CoPV) is one of the best PP that describes postural stability. The aim of this study was to analyze the relation between UST score and CoPV in elderly population.

Materials and methods

A sample of 38 healthy elderly subjects where divided in two groups according to their UPST score, low performance (LP, n = 11) and high performance (HP, n = 27). The correlation between UPST score and COP mean velocity (CoPmV), recorded from a posturographic test, was analyzed between both groups.

Results

An inverse correlation between UPST score and CoPmV was found in both groups. However, this was higher in the LP group (r = −0.69, P = .02) compared to the HP (r = −0.39, P = .04).

Conclusions

Based on the results of this investigation, it may be concluded that the achievement on UPST has an inverse relationship with CoPmV, especially in subjects with low performance in the UPST.     

Temporal pattern of neuronal insulin release during Caenorhabditis elegans aging: Role of redox homeostasis

The insulin‐IGF‐1/DAF‐2 pathway has a central role in the determination of aging and longevity in Caenorhabditis elegans and other organisms. In this paper, we measured neuronal insulin secretion (using INS‐22::Venus) during C. elegans lifespan and monitored how this secretion is modified by redox homeostasis. We showed that INS‐22::Venus secretion fluctuates during the organism lifetime reaching maximum levels in the active reproductive stage. We also demonstrate that long‐lived daf‐2 insulin receptor mutants show remarkable low levels of INS‐22::Venus secretion. In contrast, we found that short‐lived mutant worms that lack the oxidation repair enzyme MSRA‐1 show increased levels of INS‐22::Venus secretion, specifically during the reproductive stage. MSRA‐1 is a target of the insulin‐IGF‐1/DAF‐2 pathway, and the expression of this antioxidant enzyme exclusively in the nervous system rescues the mutant insulin release phenotype and longevity. The msra‐1 mutant phenotype can also be reverted by antioxidant treatment during the active reproductive stage. We showed for the first time that there is a pattern of neuronal insulin release with a noticeable increment during the peak of reproduction. Our results suggest that redox homeostasis can modulate longevity through the regulation of insulin secretion, and that the insulin‐IGF‐1/DAF‐2 pathway could be regulated, at least in part, by a feedback loop. These findings highlight the importance of timing for therapeutic interventions aimed at improving health span.