Comparative study of G- and C-banded chromosomes of five species of Microtidae: a chromosomal evolution analysis

G-banded karyotypes were compared in the following species of Microtidae: Microtus nivalis, M. cabrerae, M. arvalis, and Arvicola sapidus. Previous observations on A. sapidus and A. terrestris were also incorporated in this study. The results show that Robertsonian translocations and pericentric inversions are common mechanisms involved in the karyotypic evolution of this group. Interspecific differences on the G-banding patterns were also analysed, and an attempt was made to establish a presumptive phylogenetic tree.     

Determining the roles of father absence and age at menarche in female psychosocial acceleration

Paternal investment theory and psychosocial acceleration theory hold that father absence and stressful experiences, respectively, accelerate reproductive development. Accumulating evidence is consistent with these theories yet important questions remain. In this study, we use a two-part structural equation model and data from 342 female undergraduates to address two of these questions: First, what is the role of father absence in female psychosocial acceleration, controlling potentially confounding aspects of environment and family structure? Second, to what extent does age at menarche mediate environmental and family structure effects on sexual debut? Findings indicated that many aspects of environment and family structure could be summarized with two factors—socio-economic status (SES) and fragmented family structure. We found that among those who had experienced sexual debut, exposure to temporary father departure (one year or more) in the context of an intact family hastened menarche, which in turn accelerated sexual debut. However, this type of father absence did not predict experience of sexual debut (or not). Fragmented family structure (which also implies some degree of father absence) appeared to increase the likelihood that participants had experienced sexual debut, but did not predict age at menarche or age at sexual debut among who had debuted. SES was not associated with any aspects of reproductive development, controlling for fragmented family structure and age. We discuss our findings in relation to paternal investment theory, psychosocial acceleration theory, and life history theory. We then lay out future directions for researchers aiming to clarify the role of environment in reproductive trajectories.     

Trends in grass pollen season in southern Spain

The main characteristics of Poaceae pollen season at 8 sites in Andalusia were studied. Special attention was paid in the trends of grass pollen-season start and peak dates. Moreover, we analyse the intensity of the grass pollen season over the study period as well as potential temporal and spatial patterns in these data. Statistical analysis was performed to determine the possible influence of weather-related parameters on variations in the grass pollen season. Main results show an advance in the start and peak of grass pollen season and an increase in the annual Pollen Index and in the severity of the season (days > 25 pollen grains/m³). The future consequences of these changes in grass phenology could be related with changes in land use and also in pollinosis symptoms due to the higher concentrations recorded but also to the variations on pollen season dates.     

Hiperparatiroidismo secundario en el cáncer de próstata avanzado

Background and ObjectiveHigh parathyroid hormone (PTH) concentrations are associated with increased bone resorption and bone matrix degradation. Some studies show elevated PTH concentrations and hypocalcemia in patients with advanced prostate carcinoma, although the pathophysiological significance of these findings is not well defined.Materials and methodsWe performed a retrospective study of 60 patients diagnosed with advanced prostate cancer (44 nonmetastatic and 16 metastatic) treated with androgen deprivation. In all patients, PTH, calcium, phosphorus, 25 (OH) vitamin D and prostate-specific antigen (PSA) were determined. Bone scintigraphy had previously been performed.ResultsIn patients with bone metastases, mean concentrations were as follows: calcium 9.19 mg/dl, phosphorus 3.47 mg/dl, 25 (OH) vitamin D 13.85 ng/ml, PTH 66.8 pg/ml and total PSA 101.27 ng/ml. For those without bone metastases, the results were calcium 9.39 mg/dl, phosphorus 3.38 mg/dl, 25 (OH) vitamin D 20.50 ng/ml, PTH 52.23 pg/ml and total PSA 2.52 ng/ml. PTH levels were significantly higher in patients with prostate cancer and bone metastases than in those without metastases (p=0.03). Vitamin D levels were also significantly lower in this group (p=0.03). There were no differences in other values.ConclusionsThe present study found increased PTH concentrations in patients with advanced prostate cancer. This finding could be useful to predict disease progression.     

Molecular imprinted ormosils for nafcillin recognition by room temperature phosphorescence optosensing

Nafcillin imprinted sol-gels were used as specific binding materials for the room temperature phosphorescence (RTP) recognition of nafcillin using a flow injection system. Selective and reversible binding of the template to imprinted sol-gels could be observed by tailoring the hydrophobic/hydrophilic balance of the materials. Also, the possibility of minimizing non-specific interactions was evaluated by end-capping with trimethyl silyl groups. Control experiments were performed with non imprinted reference sol-gels. The recognition mechanism and the analytical potential of these materials for developing stable, selective and sensitive approaches for nafcillin recognition in real samples are outlined.     

Patterns and mechanisms of temporal resource partitioning among bee species visiting basil (Ocimum basilicum) flowers

The way in which flower visitors share floral resources or compete for them throughout the day is a decisive factor for the effectiveness of pollination. We described daily rhythms of flower visitation by bee species and tested whether such patterns depend on: (1) the body size of the species, (2) the daily patterns of variation in weather and nectar standing crop, and (3) the effects of weather on the daily rhythm of variation in nectar standing crop. After 1 year of biweekly samplings, we encountered 56 bee species visiting basil flowers. Larger bee species were more active in the cooler and more humid hours of the morning. Smaller species foraged later, during the warmer and drier hours. Throughout the day, nectar volume decreased. In the laboratory, we determined a positive effect of increase in temperature on nectar volume, unlike the negative correlation recorded in the field. Nectar volume decreased in plants under experimental drought, showing similarity with the driest hours of the day. The daily cycle of temperature is the fundamental factor that, directly and indirectly, via air humidity, soil moisture, and nectar supply, influences bee activity according to body size and physiological attributes. In the field, the positive effect of increasing temperatures on nectar volume is masked by a stronger, negative effect of decreasing air humidity and soil moisture throughout the day.     

Extraction of tetracycline from fermentation broth using aqueous two-phase systems composed of polyethylene glycol and cholinium-based salts

Aiming at developing not only cheaper but also biocompatible and sustainable extraction and purification processes for antibiotics, in this work it was evaluated the ability of aqueous two-phase systems (ATPS) composed of polyethylene glycol (PEG) and cholinium-based salts to extract tetracycline from the fermented broth of Streptomyces aureofaciens. Conventional polymer/salt and salt/salt ATPS were also studied for comparison purposes. The novel systems here proposed are able to extract tetracycline directly from the fermentation broth with extraction efficiencies higher than 80%. A tailored extraction ability of these systems can also be achieved, with preferential extractions either for the polymer- or salt-rich phases, and which further depend on the cholinium-based salt employed. The gathered results support the applicability of biocompatible ATPS in the extraction of antibiotics from complex matrices and can be envisaged as valuable platforms to be applied at the industrial level by pharmaceutical companies.     

When galectins recognize glycans: from biochemistry to physiology and back again

In the past decade, increasing efforts have been devoted to the study of galectins, a family of evolutionarily conserved glycan-binding proteins with multifunctional properties. Galectins function, either intracellularly or extracellularly, as key biological mediators capable of monitoring changes occurring on the cell surface during fundamental biological processes such as cellular communication, inflammation, development, and differentiation. Their highly conserved structures, exquisite carbohydrate specificity, and ability to modulate a broad spectrum of biological processes have captivated a wide range of scientists from a wide spectrum of disciplines, including biochemistry, biophysics, cell biology, and physiology. However, in spite of enormous efforts to dissect the functions and properties of these glycan-binding proteins, limited information about how structural and biochemical aspects of these proteins can influence biological functions is available. In this review, we aim to integrate structural, biochemical, and functional aspects of this bewildering and ancient family of glycan-binding proteins and discuss their implications in physiologic and pathologic settings.