Familial mediterranean fever (FMF) in Moroccan Jews: Demonstration of a founder effect by extended haplotype analysis

Familial Mediterranean fever (FMF) is an autosomal recessive disease causing attacks of fever and serositis. The FMF gene (designated “MEF”) is on 16p, with the gene order 16cen–D16S80–MEF–D16S94–D16S283–D16S291–16pter. Here we report the association of FMF susceptibility with alleles at D16S94, D16S283, and D16S291 among 31 non-Ashkenazi Jewish families (14 Moroccan, 17 non-Moroccan). We observed highly significant associations at D16S283 and D16S291 among the Moroccan families. For the non-Moroccans, only the allelic association at D16S94 approached statistical significance. Haplotype analysis showed that 18/25 Moroccan FMF chromosomes, versus 0/21 noncarrier chromosomes, bore a specific haplotype for D16S94–D16S283–D16S291. Among non-Moroccans this haplotype was present in 6/26 FMF chromosomes versus 1/28 controls. Both groups of families are largely descended from Jews who fled the Spanish Inquisition. The strong haplotype association seen among the Moroccans is most likely a founder effect, given the recent origin and genetic isolation of the Moroccan Jewish community. The lower haplotype frequency among non-Moroccan carriers may reflect differences both in history and in population genetics.     

Volume changes correlate with entropies and enthalpies in the formation of nucleic acid homoduplexes: Differential hydration of A and B conformations

We have used a combination of densimetric, calorimetric, and uv absorption techniques to obtain a complete thermodynamic characterization for the formation of nucleic acid homoduplexes of known sequence and conformation. The volume change ΔV accompanying the formation of four duplexes was interpreted to reflect changes in hydration based on the electrostriction phenomenon. In 10 mM sodium phosphate buffer at pH 7, the magnitude of the measured ΔV's ranged from ?2.0 to +7.2 ml/mol base pair and followed the order of poly(rA) · poly(dT) ～ poly(dA) · poly(dT) < poly(rA) · poly(dU) ～ poly(rA) · poly(rU). Inclusion of 100 mM NaCl in the same buffer gave the range of ?17.4 to ?2.3 mL/mol base pair and the following order: poly(dA) · poly(dT) < poly(rA) · poly(dT) < poly(rA) · poly(rU) ～ poly(rA) ～ polyr(dU). Standard thermodynamic profiles of forming these duplexes from their corresponding complementary single strands indicated similar free energies that resulted from the compensation of favorable enthalpies with unfavorable entropies along with a similar counterion uptake at both ionic strengths. The differences in these compensating effects of entropy and enthalpy correlated very well with the volume change measurements in a manner suggesting that the homoduplexes in the B conformation are more hydrated than are those in the A conformation. Moreover, the increased thermal stability of these homoduplexes resulted from an increase in the salt concentration corresponding to larger hydration levels as reflected by the ΔV results. © 1993 John Wiley & Sons, Inc.     

Hyposensitive canopy conductance renders ecosystems vulnerable to meteorological droughts

Increased meteorological drought intensity with rising atmospheric demand for water (hereafter vapor pressure deficit [VPD]) increases the risk of tree mortality and ecosystem dysfunction worldwide. Ecosystem-scale water-use strategy is increasingly recognized as a key factor in regulating drought-related ecosystem responses. However, the link between water-use strategy and ecosystem vulnerability to meteorological droughts is poorly established. Using the global flux observations, historic hydroclimatic data, remote-sensing products, and plant functional-trait archive, we identified potentially vulnerable ecosystems, examining how ecosystem water-use strategy, quantified by the percentage bias (δ) of the empirical canopy conductance sensitivity to VPD relative to the theoretical value, mediated ecosystem responses to droughts. We found that prevailing soil water availability substantially impacted δ in dryland regions where ecosystems with insufficient soil moisture usually showed conservative water-use strategy, while ecosystems in humid regions exhibited more pronounced climatic adaptability. Hyposensitive and hypersensitive ecosystems, classified based on δ falling below or above the theoretical sensitivity, respectively, achieved similar net ecosystem productivity during droughts, employing different structural and functional strategies. However, hyposensitive ecosystems, risking their hydraulic system with a permissive water-use strategy, were unable to recover from droughts as quickly as hypersensitive ones. Our findings highlight that processed-based models predicting current functions and future performance of vegetation should account for the greater vulnerability of hyposensitive ecosystems to intensifying atmospheric and soil droughts.     

Predator response to the coloured eyespots and defensive posture of Colombian four-eyed frogs

Deimatic displays, where sudden changes in prey appearance elicit aversive predator reactions, have been suggested to occur in many taxa. These (often only putative) displays frequently involve different components that may also serve antipredator functions via other mechanisms (e.g., mimicry, warning signalling, body inflation). The Colombian four-eyed frog, Pleurodema brachyops, has been suggested to gain protection against predation through putative deimatic displays where they inflate and elevate the posterior part of their body revealing eye-like colour markings. We exposed stationary artificial frogs to wild predators to test whether the two components (eyespot/colour markings, defensive posture) of their putative deimatic display, and their combination, provide protection from predation without the sudden change in appearance. We did not detect any obvious additive effect of defensive posture and eyespots/colour markings on predation risk, but found a marginally significant trend for model frogs in the resting posture to be less attacked when displaying eyespots/colour markings than when they were not, suggesting that the presence of colour markings/eyespots may provide some protection on its own. Additionally, we found that models in a resting posture were overall more frequently attacked on the head than models in a defensive posture, indicating that a defensive posture alone could help redirect predator attacks to non-vital parts of the body. The trends found in our study suggest that the different components of P. brachyops' coloration may serve different functions during a deimatic display, but further research is needed to elucidate the role of each component when accompanied by sudden prey movement.     

Erk1/2 signaling mediates the HGF-induced protection against ethanol and acetaldehyde-induced toxicity in the pancreatic RINm5F cell line

Alcohol-induced pancreas damage remains as one of the main risk factors for pancreatitis development. This disorder is poorly understood, particularly the effect of acetaldehyde, the primary alcohol metabolite, in the endocrine pancreas. Hepatocyte growth factor (HGF) is a protective protein in many tissues, displaying antioxidant, antiapoptotic, and proliferative responses. In the present work, we were focused on characterizing the response induced by HGF and its protective mechanism in the RINm5F pancreatic cell line treated with ethanol and acetaldehyde. RINm5F cells were treated with ethanol or acetaldehyde for 12 h in the presence or not of HGF (50 ng/ml). Cells under HGF treatment decreased the content of reactive oxygen species and lipid peroxidation induced by both toxics, improving cell viability. This effect was correlated to an improvement in insulin expression impaired by ethanol and acetaldehyde. Using a specific inhibitor of Erk1/2 abrogated the effects elicited by the growth factor. In conclusion, the work provides mechanistic evidence of the HGF-induced-protective response to the alcohol-induced damage in the main cellular component of the endocrine pancreas.     

EMG biofeedback of the abductor pollicis brevis in piano performance

The aim of the present study was to apply EMG biofeedback as an auxiliary to piano teaching techniques. We studied the changes in integrated electromyographic activity, using the abductor pollicis brevis functioning as an agonist during the teaching of identical selective movements of piano playing in two groups, one with EMG biofeedback and the other following traditional method of instruction. The analysis of variance revealed an increase in the peak amplitude and the relaxation rate values for the biofeedback group. These results have implications for the application of piano playing techniques and reveal EMG biofeedback as an aid in the teaching of thumb attack with the abductor pollicis brevis as agonist.We are grateful for the valuable assistance of Dr. Jaime Vila (Professor of Therapy and Behavioral Modification, Faculty of Psychology, Granada), the cooperation of students at the Juventudes Musicales Music School, Santa Fe and at the Victoria Eugenia Conservatoire, (Granada), the Statistical Analysis Centre of University of Filosofia y Letras de Granada; Professor Enrique Garcia Fernandez-Abasal (Complutense University) for the design of the interface and software.     

The 59-kDa polypeptide constituent of 8–10-nm cytoplasmic filaments in Neurospora crassa is a pyruvate decarboxylase

The fungus Neurospora crassa harbors large amounts of cytoplasmic filaments which are homopolymers of a 59-kDa polypeptide (P59Nc). We have used molecular cloning, sequencing and enzyme activity measurement strategies to demonstrate that these filaments are made of pyruvate decarboxylase (PDC, EC 4.1.1.1), which is the key enzyme in the glycolytic-fermentative pathway of ethanol production in fungi, and in certain plants and bacteria. Immunofluorescence analyses of 8–10-nm filaments, as well as quantitative Northern blot studies of P59Nc mRNA and measurements of PDC activity, showed that the presence and abundance of PDC filaments depends on the metabolic growth conditions of the cells. These findings may be of relevance to the biology of ethanol production by fungi, and may shed light on the nature and variable presence of filament bundles described in fungal cells.     

Influence of plant domestication on plant-pollinator interactions: Floral attributes and floral visitor communities in wild and cultivated squash plants

Premise

Domestication of plant species results in phenotypic modifications and changes in biotic interactions. Most studies have compared antagonistic plant-herbivore interactions of domesticated plants and their wild relatives, but little attention has been given to how domestication influences plant-pollinator interactions. Floral attributes and interactions of floral visitors were compared between sister taxa of the genus Cucurbita (Cucurbitaceae), the domesticated C. moschata, C. argyrosperma ssp. argyrosperma and its wild progenitor C. argyrosperma ssp. sororia in the place of origin.

Methods

We conducted univariate and multivariate analyses to compare floral morphological traits and analyzed floral reward (nectar and pollen) quantity and quality between flowers of wild and domesticated Cucurbita taxa. Staminate and pistillate flowers of all three taxa were video recorded, and visitation and behavior of floral visitors were registered and analyzed.

Results

Most floral morphological characteristics of flowers of domesticated taxa were larger in both staminate and pistillate flowers. Staminate and pistillate flowers presented distinct correlations between floral traits and integration indices between domesticated and wild species. Additionally, pollen quantity and protein to lipid ratio were greater in domesticated species. Cucurbit pollen specialists, Eucera spp., had the highest probability of visit for all Cucurbita taxa.

Conclusions

We provide evidence that floral traits of domesticated and wild Cucurbita species experienced different selection pressures. Domesticated Cucurbita species may have more resources invested towards floral traits, thereby increasing attractiveness to pollinators and potentially plant reproductive success. Wild ancestor plant populations should be conserved in their centers of origin to preserve plant-pollinator interactions.