Comparative study of the antioxidant activity of the essential oils of five plants against the H2O2 induced stress in Saccharomyces cerevisiae

The purpose of this work was to investigate the protective effect of five essential oils (EOs); Rosmarinus officinalis, Thymus vulgaris, Origanum compactum Benth., Eucalyptus globulus Labill. and Ocimum basilicum L.; against oxidative stress induced by hydrogen peroxide in Saccharomyces cerevisiae. The chemical composition of the EOs was analyzed by gas chromatography (GC) and gas chromatography-mass spectrometry (GC/MS). The in vitro antioxidant activity was evaluated and the protective effect of EOs was investigated. Yeast cells were pretreated with different concentrations of EOs (6.25–25 µg/ml) for an hour then incubated with H₂O₂ (2 mM) for an additional hour. Cell viability, antioxidants (Catalase, Superoxide dismutase and Glutathione reductase) and metabolic (Succinate dehydrogenase) enzymes, as well as the level of lipid peroxidation (LPO) and protein carbonyl content (PCO) were evaluated. The chemical composition of EOs has shown the difference qualitatively and quantitatively. Indeed, O. compactum mainly contained Carvacrol, O. basilicum was mainly composed of Linalool, T. vulgaris was rich in thymol, R. officinalis had high α-Pinene amount and for E. globulus, eucalyptol was the major compound. The EOs of basil, oregano and thyme were found to possess the highest amount of total phenolic compounds. Moreover, they have shown the best protective effect on yeast cells against oxidative stress induced by H₂O₂. In addition, in a dose dependent manner of EOs in yeast medium, treated cells had lower levels of LPO, lower antioxidant and metabolic enzymes activity than cells exposed to H₂O₂ only. The cell viability was also improved. It seems that the studied EOs are efficient natural antioxidants, which can be exploited to protect against damages and serious diseases related to oxidative stress.     

Variable selection patterns on the labellum shape of Geoblasta pennicillata,a sexually deceptive orchid

By mimicking shape and female mating pheromones, flowers of sexually deceptive orchids attract sexually excited males which pollinate them while trying to copulate. Although many studies have demonstrated the crucial importance of odour signals in these systems, most flowers pollinated by pseudocopulation resemble, at least superficially, an insect body and these visual cues may be important to cheat pollinators. In this 2‐year study, we show that the shape of the labellum of Geoblasta pennicillata is a target of pollinator‐mediated natural selection. Contrary to our expectations, plants with a labellum shape more similar to female wasps were not favoured. The strength and pattern of phenotypic selection varied between study years and sexual functions. Although selection through female success was probably associated to the fine‐tuning of the mechanical fit between flower form and male wasp, shape was the target of natural selection through male success in both study years indicating that male wasps use this trait when choosing flowers. The imperfect mimicry and patterns of selection observed indicated that an exact imitation is not needed to attract and deceive the pollinators and they suggested a receiver perceptual bias towards uncommon phenotypes.     

Genomic architecture of ecologically divergent body shape in a pair of sympatric crater lake cichlid fishes

Determining the genetic bases of adaptations and their roles in speciation is a prominent issue in evolutionary biology. Cichlid fish species flocks are a prime example of recent rapid radiations, often associated with adaptive phenotypic divergence from a common ancestor within a short period of time. In several radiations of freshwater fishes, divergence in ecomorphological traits — including body shape, colour, lips and jaws — is thought to underlie their ecological differentiation, specialization and, ultimately, speciation. The Midas cichlid species complex (Amphilophus spp.) of Nicaragua provides one of the few known examples of sympatric speciation where species have rapidly evolved different but parallel morphologies in young crater lakes. This study identified significant QTL for body shape using SNPs generated via ddRAD sequencing and geometric morphometric analyses of a cross between two ecologically and morphologically divergent, sympatric cichlid species endemic to crater Lake Apoyo: an elongated limnetic species (Amphilophus zaliosus) and a high‐bodied benthic species (Amphilophus astorquii). A total of 453 genome‐wide informative SNPs were identified in 240 F₂ hybrids. These markers were used to construct a genetic map in which 25 linkage groups were resolved. Seventy‐two segregating SNPs were linked to 11 QTL. By annotating the two most highly supported QTL‐linked genomic regions, genes that might contribute to divergence in body shape along the benthic–limnetic axis in Midas cichlid sympatric adaptive radiations were identified. These results suggest that few genomic regions of large effect contribute to early stage divergence in Midas cichlids.     

Variation in human limb joint articular morphology

Objectives

Synovial joints in human limbs strike a balance between mobility, stability, and articular fit, yet little is known about how these conflicting demands pattern intraspecific variation in articular shape. In this study, we use geometric morphometrics to establish the apportionment and magnitude of morphological variance of the articular surfaces of the human shoulder, elbow, hip, and knee. We hypothesize that variances will be comparable between articulating surfaces within a joint and will be larger in joints with smaller ranges of motion, given their plurality of functional demands.

Materials and Methods

Three-dimensional landmarks were taken on the articular surfaces of the glenohumeral, humeroulnar, acetabulofemoral, and tibiofemoral joints from CT scans of 200 skeletons from the University of Tennessee Donated Skeletal Collection (84 females, 116 males). Root mean-squared distances between articulations calculated from Procrustes shape coordinates were used to determine variance distributions.

Results

We found no difference in variances for each articular surface between the sexes or between left and right articular surfaces. A high range of motion is associated with greater morphological variance; however, this pattern is largely driven by the concave articular surfaces of each joint, which consistently exhibit statistically greater variance than their convex counterparts.

Discussion

The striking pattern of differential variance between articulating morphologies points to potential disparities in development between them. Consistently higher variance in concave surfaces may relate to chondral modeling theory for the formation of joints. Establishing intraspecific morphological variance patterns is a first step in understanding coordinated evolution among articular features.     

Allometry,merism, and tooth shape of the upper deciduous M2 and permanent M1

The aims of this study were to investigate the effect of allometry on the shape of dm² and M¹ crown outlines and to examine whether the trajectory and magnitude of scaling are shared between species. The sample included 160 recent Homo sapiens, 28 Upper Paleolithic H. sapiens, 10 early H. sapiens, and 33 H. neanderthalensis (Neandertal) individuals. Of these, 97 were dm²/M¹ pairs from the same individuals. A two‐block partial least squares analysis of paired individuals revealed a significant correlation in crown shape between dm² and M¹. A principal component analysis confirmed that Neandertal and H. sapiens dm² and M¹ shapes differ significantly and that this difference is primarily related to hypocone size and projection. Allometry accounted for a small but significant proportion of the total morphological variance. We found the magnitude of the allometric effect to be significantly stronger in Neandertals than in H. sapiens. Procrustes distances were significantly different between the two tooth classes in Neandertals, but not among H. sapiens groups. Nevertheless, we could not reject the null hypothesis that the two species share the same allometric trajectory. Although size clearly contributes to the unique shape of the Neandertal dm² and M¹, the largest H. sapiens teeth do not exhibit the most Neandertal‐like morphology. Hence, additional factors must contribute to the differences in dm² and M¹ crown shape between these two species. We suggest an investigation of the role of timing and rate of development on the shapes of the dm² and M¹ may provide further answers. Am J Phys Anthropol 154:104–114, 2014. © 2014 Wiley Periodicals, Inc.     

Phylogeny of the superfamily Gelechioidea (Lepidoptera: Obtectomera), with an exploratory application on geometric morphometrics

The superfamily Gelechioidea (Lepidoptera: Obtectomera) has a high species diversity. It consists of more than 18,400 described species and has a global distribution. Among it, large numbers of species were reported to be economically important to people's production and life. However, relationships among families or subfamilies in Gelechioidea have been exceptionally difficult to resolve using morphology or single gene genealogies. Multiple gene genealogies had been used in the molecular phylogenetic studies on Gelechioidea during the past years, but their phylogenetic relationships remain to be controversial mainly due to their limited taxa sampling relative to such high species diversity. In this paper, 89 ingroup species representing 55 genera are sequenced and added to the data downloaded from GenBank, and six species representing four closely related superfamilies are chosen as outgroup. The molecular phylogeny of Gelechioidea is reconstructed based on the concatenated data set composed of one mitochondrial marker (COI) and seven nuclear markers (CAD, EF-1ɑ, GAPDH, IDH, MDH, RpS5, wingless). The phylogenetic results, taking into consideration of the comparative morphological study, show that the clade of Gelechioidea is strongly supported and separated from other superfamilies, which further proves its monophyly. Five families are newly defined: Autostichidae sensu nov., Depressariidae sensu nov., Peleopodidae sensu nov., Ashinagidae sensu nov. and Epimarptidae sensu nov. Meanwhile, a monophyletic “SSABM” clade considered to be closely related is proposed for the first time, consisting of Stathmopodidae, Scythrididae, Ashinagidae, Blastobasidae and Momphidae. Moreover, geometric morphometric analyses using merged landmark data set from fore and hind wings of 118 representative species are conducted. The phenetic tree shows that the monophyly and phylogenetic relationships correspond with the results of molecular phylogeny largely, which well proves its importance and potential application in both phylogenetic reconstruction and species identification.     

Harder,better, faster,stronger: Weapon size is more sexually dimorphic than weapon biomechanical components in two freshwater anomuran species

Sexual selection influences the evolution of morphological traits that increase the likelihood of monopolizing scarce resources. When such traits are used during contests, they are termed weapons. Given that resources are typically linked to monopolizing mating partners, theory expects only males to bear weapons. In some species, however, females also bear weapons, although typically smaller than male weapons. Understanding why females bear smaller weapons can thus help us understand the selective pressures behind weapon evolution. However, most of our knowledge comes from studies on weapon size, while the biomechanics of weapons, such as the size of the muscles, efficiency, and shape are seldom studied. Our goal was to test if the theoretical expectations for weapon size sexual dimorphism also occur for weapon biomechanics using two aeglid crab species. Males of both species had larger claws which were also stronger than female claws. Male claws were also more efficient than females' claws (although we used only one species in this analysis). For weapon shape, though, only one species differed in the mean claw shape. Regarding scaling differences, in both species, male claws had higher size scaling than females, while only one species had a higher shape scaling. However, male weapons did not have higher scaling regarding strength and efficiency than females. Thus, males apparently allocate more resources in weapons than females, but once allocated, muscle and efficiency follow a similar developmental pathway in both sexes. Taken together, our results show that sexual dimorphism in weapons involves more than differences in size. Shape differences are especially intriguing because we cannot fully understand its causes. Yet, we highlight that such subtle differences can only be detected by measuring and analysing weapon shape and biomechanical components. Only then we might better understand how weapons are forged.     

Nutritional geometry of calcium and phosphorus nutrition in broiler chicks. The effect of different dietary calcium and phosphorus concentrations and ratios on nutrient digestibility

A total of 600 Ross 308-day-old male broiler chicks were used in a 28 day digestibility study to investigate the interaction between dietary calcium (Ca) and non-phytate phosphorus (nPP) on the digestibility of minerals and amino acids. Diets were formulated to be nutritionally adequate except for Ca and nPP. Fifteen mash diets based on corn and soya bean meal with varying concentrations of Ca (6.4 to 12.0 g/kg) and nPP (2.4 to 7.0 g/kg) were used. Diets were clustered around total densities of Ca and nPP of 12, 13.5 or 15.0 (g/kg) and within each density, a range of five Ca : nPP ratios (1.14 : 1, 1.5 : 1, 2.0 : 1, 2.75 : 1 and 4.0 : 1) were fed. Birds had free access to feed and water throughout the study. At day 28, birds were euthanised for the determination of apparent ileal mineral and amino acid digestibility. Data were modelled in R version 2.15 using a linear mixed-effects model and interrogation of the data was performed by fitting a low order polynomial function. At high Ca concentrations, increasing nPP led to an increase in the apparent digestibility of minerals. Apparent ileal digestibility of phosphorus (P) was enhanced with increasing dietary nPP up to 5.5 g/kg beyond which no improvements were found. Maximal Ca digestibility was found in diets with >8.0 g/kg Ca with concomitant low concentrations of nPP. Diets with a broader Ca : nPP ratio improved the digestibility of Ca but were deleterious to the digestibility of P. In this study, apparent digestibility of amino acids was broadly unaffected by dietary Ca and nPP concentrations. However, interactions between Ca and nPP were observed for the digestibility of glutamine, tyrosine and methionine (all P<0.001). Nitrogen digestibility showed discrete optima around 10.0 and 5.0 g/kg nPP and Na digestibility was maximised around 8 to 9.0 g/kg Ca and 4.5 to 5.4 g/kg nPP. These data show that the ratio of Ca : nPP is more influential to mineral digestibility than the absolute dietary concentration of each macro mineral.