Enhancing knowledge on low-value fishing species: the distinct reproductive strategy of two gurnard species

The depletion and overexploitation of several fish stock demands for a valorisation of non-target and discarded species. Nonetheless, such species are often poorly studied, and information on their biological parameters must be gathered for effective population management. For 1 year, the reproductive strategy of the piper gurnard Trigla lyra and the red gurnard Chelidonichthys cuculus was studied by monthly samples obtained from commercial boats operating on western Portuguese coast. Both species showed a biased sex ratio towards females, especially for larger length classes. Length at first maturity could be estimated only for red gurnard (22.1 and 19.9 cm for females and males, respectively) because all piper gurnard individuals caught were mature. Piper gurnard showed determinate fecundity and a short spawning season, from November to February with a peak in January, whereas red gurnard showed indeterminate fecundity and a wide spawning season, from late December to May. The relative annual fecundity estimated for red gurnard (1893 ± 728 oocytes × g⁻¹ eviscerated weight [EW]) was higher than the one estimated for piper gurnard (1018 ± 250 oocytes×g⁻¹ EW). Although important information for understanding the species dynamics is presented in this study, additional information on other life-history parameters and of species landings is required.     

Vine mealybug sex pheromone increases citrus mealybug parasitism by Anagyrus sp. near pseudococci (Girault)

The present study was aimed at elucidating the role of lavandulyl senecioate (LS), the sex pheromone of Planococcus ficus, in host selection of the parasitoid Anagyrus sp. near pseudococci. Field trials were carried out in Portugal, Italy and Israel. The effect of LS on the parasitism rate of the wasp was determined by exposing sentinel mealybugs combined with pheromone dispensers impregnated with LS, in comparison with other baits: lavandulyl isovalerate (LI); planococcyl acetate (PAc); and unbaited control traps. In addition, in order to study the host location behavior of A. sp. near pseudococci, pheromone dispensers were placed at three different distances: inside the trap, 30 or 60 cm away from the trap. The number of parasitoid females inside the traps, the number of parasitized mealybugs, and the number of days required for the first parasitoid emergence were recorded. The response of A. sp. near pseudococci females to different doses of LS (25–1350 μg) was also evaluated using sticky plate traps. The rate of mealybug parasitism by A. sp. near pseudococci was significantly increased by LS in the three parasitoid populations. PAc and LI had no significant effect on the wasp parasitism rate in most of the trials. However, the Italian population of the parasitoid responded to PAc, showing apparently a different behavioral pattern. The number of parasitoid females trapped did not significantly differ between tested doses of LS. The use of LS as an arrestant in host location by the A. sp. near pseudococci female is discussed.     

Evidence for divergent evolution of growth temperature preference in sympatric Saccharomyces species

The genus Saccharomyces currently includes eight species in addition to the model yeast Saccharomyces cerevisiae, most of which can be consistently isolated from tree bark and soil. We recently found sympatric pairs of Saccharomyces species, composed of one cryotolerant and one thermotolerant species in oak bark samples of various geographic origins. In order to contribute to explain the occurrence in sympatry of Saccharomyces species, we screened Saccharomyces genomic data for protein divergence that might be correlated to distinct growth temperature preferences of the species, using the dN/dS ratio as a measure of protein evolution rates and pair-wise species comparisons. In addition to proteins previously implicated in growth at suboptimal temperatures, we found that glycolytic enzymes were among the proteins exhibiting higher than expected divergence when one cryotolerant and one thermotolerant species are compared. By measuring glycolytic fluxes and glycolytic enzymatic activities in different species and at different temperatures, we subsequently show that the unusual divergence of glycolytic genes may be related to divergent evolution of the glycolytic pathway aligning its performance to the growth temperature profiles of the different species. In general, our results support the view that growth temperature preference is a trait that may have undergone divergent selection in the course of ecological speciation in Saccharomyces.     

New evidence of Ceratosaurus (Dinosauria: Theropoda) from the Late Jurassic of the Lusitanian Basin,Portugal

A theropod assigned to Ceratosaurus was previously reported from the Portuguese Lusitanian Basin based on a limited number of elements of a single individual. Here, we describe newly discovered elements that likely pertain to same, earlier described, specimen. The new elements provide additional evidence that the range of Ceratosaurus spanned from what is now North America into Europe. Previously, some differences were noted between the Portuguese specimens and the North American Ceratosaurus. We consider these differences to be trivial and attribute them to individual variation and/or ontogeny. The following set of features (lesser trochanter positioned low on the femur; crista tibiofibularis obliquely oriented with respect to the axis of the femoral shaft; infrapopliteal ridge present posteriorly on the femur; large cnemial crest; and medial condyle of the tibia continuous with proximal end) indicate that the Portuguese specimen is assignable to Ceratosaurus. This record constitutes one of the scarce evidence of basal ceratosaurian theropods in the Late Jurassic of Europe. Despite the abundance, diversity and wide geographical distribution of ceratosaurs during the Late Cretaceous, its early evolutionary history remains poorly understood. The Portuguese specimens constitute an important evidence for the knowledge of the paleobiogeographic evolution of the clade during the Late Jurassic.     

Women’s Satisfaction with Body Image before Pregnancy and Body Mass Index 4 Years after Delivery in the Mothers of Generation XXI

Background

Body image satisfaction (BIS) influences body weight regulation and may contribute to long-term healthier lifestyle after pregnancy. Thus, we aimed to assess the association between BIS before pregnancy and body mass index (BMI) 4 years after the index pregnancy.

Methods

As part of the follow-up of a birth cohort, 3612 women with prepregnancy BMI >18.5 kg/m² were reevaluated 4 years after the birth of a child. BIS was defined as the difference between perceived and ideal body size before pregnancy, assessed by Stunkard Silhouettes after birth. The associations of BIS with BMI change (continuous) and BMI classes at 4 years, based on measured weight and height, were estimated using linear and multinomial regression, respectively.

Results

Among women with normal prepregnancy BMI, those who felt too small, regarding their ideal, had a 0.25 kg/m² smaller increase in BMI within 4 years and a lower likelihood of becoming overweight or obese [multivariate-adjusted odds ratio (OR) = 0.63; 95% confidence interval (95%CI): 0.44–0.91 and OR = 0.21; 95%CI: 0.05–0.91, respectively) than those satisfied with body image. Feeling too large was associated with a 0.41 kg/m² larger increase in BMI and a higher risk of becoming overweight or obese (OR = 2.12; 95%CI:1.73–2.59 and OR = 3.42; 95%CI:2.02–5.79, respectively). A similar, non-significant, trend was observed for overweight women. Obese women who felt too large had a non-significant decrease in BMI.

Conclusions

BIS plays a role in maternal body weight after delivery. Realistic body size goals may promote the motivation to lose weight and contribute to higher success in attaining them.     

Five-membered iminocyclitol α-glucosidase inhibitors: Synthetic,biological screening and in silico studies

The design and synthesis of a small library of pyrrolidine iminocyclitol inhibitors with a structural similarity to 1,4-dideoxy-1,4-imino-d-arabitol (DAB-1) is reported. This library was specifically designed to gain a better insight into the mechanism of inhibition of glycosidases by polyhydroxylated pyrrolidines or iminocyclitols. Pyrrolidine-3,4-diol 15a and pyrrolidine-3,4-diol diacetate 15b had emerged as the most potent α-glucosidase inhibitors in the series. Docking studies performed with an homology model of α-glucosidase disclosed binding poses for compounds 15a, 15b, 16a, and 16a′ occupying the same region as the NH group of the terminal ring of acarbose and suggest a closer and stronger binding of compound 15a and 15b with the enzyme active site residues. Our studies indicate that 2 or 5-hydroxyl substituents appear to be vital for high inhibitory activity.     

Microphytoplankton assemblages in shallow waters at Admiralty Bay (King George Island,Antarctica) during the summer 2002–2003

Microphytoplankton populations were studied in shallow coastal water (<60 m) near the Brazilian Antarctic Station Comandante Ferraz (EACF) and three reference areas in Admiralty Bay in early and late summer (2002–2003). Phytoplankton was diverse (113 taxa), but not abundant (10³ cells l⁻¹). The highest abundances (>10⁴ cells l⁻¹) were caused by pennate benthic diatoms (Fragilaria striatula Lyngbye) that occurred mainly in early summer, associated with the presence of ice. In late summer, when the water temperature (−0.4 to 1.5°C), salinity (34 to 35), and phosphate (2.6 to 4.5 μmol l⁻¹) were highest and the dissolved oxygen was lowest (6.4 to 2.9 ml l⁻¹), centric diatoms (Thalassiosira spp.) were more abundant, suggesting an influence of oceanic waters. Phytoplankton abundance (≤10² cells l⁻¹) and chlorophyll a concentrations (0.22 μg l⁻¹) were lowest close to EACF. Pennate diatoms were dominant close to shore and in surface waters elsewhere, probably because of ice melting or sediment resuspension caused by water mixing.     

Time-course determination of plasmid content in eukaryotic and prokaryotic cells using Real-Time PCR

A Real-Time PCR method was developed to monitor the plasmid copy number (PCN) in Escherichia coli and Chinese hamster ovary (CHO) cells. E. coli was transformed with plasmids containing a ColE1 or p15A origin of replication and CHO cells were transfected with a ColE1 derived plasmid used in DNA vaccination and carrying the green fluorescent protein (GFP) reporter gene. The procedure requires neither specific cell lysis nor DNA purification and can be performed in <30 min with dynamic ranges covering 0.9 pg–55 ng, and 5.0 pg–2.5 ng of plasmid DNA (pDNA) for E. coli and CHO cells, respectively. Analysis of PCN in E. coli batch cultures revealed that the maximum copy number per cell is attained in mid-exponential phase and that this number decreases on average 80% towards the end of cultivation for both types of plasmids. The plasmid content of CHO cells determined 24 h post-transfection was around 3 × 10⁴ copies per cell although only 37% of the cells expressed GFP one day after transfection. The half-life of pDNA was 20 h and around 100 copies/cell were still detected 6 days after transfection.