Electrophysiological Responses to Affective Stimuli in Neglectful Mothers

Results illustrating an atypical neural processing in the early and late differentiation of infant faces have been obtained with neglectful mothers. The present study explores whether a different pattern of response is observed when using non-infant affective pictures. We examined the event-related evoked potentials and induced delta, theta and alpha activity in 14 neglectful mothers and 14 control mothers elicited while categorizing positive, negative and neutral pictures from the International Affective Picture System. Self-reports of anhedonia and empathy were also recorded. Early posterior negativity, P200 and late positive potential components were modulated by the emotional content of pictures in both groups. However, the LPP waveform had a more delayed and more attenuated maximum in neglectful mothers than in control mothers. Oscillatory responses indicated lower power increases for neglectful mothers than for control mothers in delta (1–4 Hz), theta (4–8 Hz) and lower alpha (8–10 Hz) bands at frontal sites, and a more consistent increase for neglectful mothers in theta and lower alpha bands at occipital sites, especially for negative pictures. These findings help us to better understand the limits of emotional insensitivity in neglectful mothers.     

Degradation of polyvinyl alcohol under mechanothermal stretching

Mechanical and thermal properties of polyvinyl alcohol (PVA) are characterized and analyzed using in situ X-ray photoelectron spectroscopy (XPS) and quantum chemistry calculations. It is found that the carbon peaks—commonly used as the reference for spectroscopic analysis—shift under mechanical and thermal stretching. Results also indicate that, at different temperatures and among the various functional groups present in PVA, the carbon in the C–O group is the most stable. Computational calculations showed that Hartree–Fock/10-31G (d) reproduces the binding energy of core carbon electrons with an accuracy of 95 %, which is enough to characterize bonds, allowing the results of the spectroscopic analysis to be corroborated.

Synthesis of 7-(β-D-Glucopyranosyl)-6-Thiotheophylline and 7-(α-D-Arabinopyranosyl)-6-Thiotheopwlline. Conformational Study of the Peracetyl Derivatives.

Abstract

The synthesis of two 7-glycosyl-6-thiotheophylline nucleosides where the sugar moieties are β-D-glucose (1b) and α-D-arabinose (2b) is reported. The syn-anti equilibrium of the peracetyl derivatives was studied by the line-shape and the ¹H-NMR nOe methods, and molecular mechanics analysis.     

Activin A Suppresses Osteoblast Mineralization Capacity by Altering Extracellular Matrix (ECM) Composition and Impairing Matrix Vesicle (MV) Production

During bone formation, osteoblasts deposit an extracellular matrix (ECM) that is mineralized via a process involving production and secretion of highly specialized matrix vesicles (MVs). Activin A, a transforming growth factor-β (TGF-β) superfamily member, was previously shown to have inhibitory effects in human bone formation models through unclear mechanisms. We investigated these mechanisms elicited by activin A during in vitro osteogenic differentiation of human mesenchymal stem cells (hMSC). Activin A inhibition of ECM mineralization coincided with a strong decline in alkaline phosphatase (ALP¹) activity in extracellular compartments, ECM and matrix vesicles. SILAC-based quantitative proteomics disclosed intricate protein composition alterations in the activin A ECM, including changed expression of collagen XII, osteonectin and several cytoskeleton-binding proteins. Moreover, in activin A osteoblasts matrix vesicle production was deficient containing very low expression of annexin proteins. ECM enhanced human mesenchymal stem cell osteogenic development and mineralization. This osteogenic enhancement was significantly decreased when human mesenchymal stem cells were cultured on ECM produced under activin A treatment. These findings demonstrate that activin A targets the ECM maturation phase of osteoblast differentiation resulting ultimately in the inhibition of mineralization. ECM proteins modulated by activin A are not only determinant for bone mineralization but also possess osteoinductive properties that are relevant for bone tissue regeneration.The quality of bone tissue is determined by the balanced action of the anabolic bone cells, the osteoblasts, and their catabolic counterparts, the osteoclasts. This process of bone remodeling occurs throughout life and can be influenced by a wide variety of molecules, having ultimately an impact on the quality of bone (1, 2). Activins and inhibins are members of the TGF-β superfamily with predominant antagonistic effects in their classically known target tissues, such as in gonadotropin producing cells in the pituitary and their role in reproduction (3, 4). Like other TGF-β member, activins elicit biological responses by binding to type I and II serine/threonine kinase receptors at the cell surface. Upon ligand binding, signaling is further transduced in the cytoplasm by phosphorylated Smad protein complexes that once in the nucleus regulate gene expression. This signaling pathway is highly complex because of crosstalk between different ligands (Activins, BMPs, TGF-β) binding to multiple serine/threonine kinase receptors that activate different Smad proteins signaling to the nucleus. Activin is known to signal using type II receptors ACVR2A or ACVR2B and the type I receptor ACVRIB (shared with BMPs) activating Smad2 and 3 proteins (shared with TGF-β). Inhibins exert their inhibitory effects on activin by competitive binding to the activin receptors in the presence of betaglycan. This signaling regulates a wide array of biological activities from cell proliferation, differentiation to tumor development and endocrine signaling (5, 6) in many cell lineages like hematopoietic (7, 8) and monocyte/macrophage (9, 10). Several consequences of these reproductive hormones, especially those of activin A, are also described in relation to bone metabolism. Activin A is present in bone tissue (11, 12) affecting both osteoclasts and osteoblasts. While having a consistent pro-osteoclastogenic effect (9, 13), the activin A impact on osteoblast differentiation is more controversial (see (14) for review) Several reports support a stimulatory effect of activin A on osteoblast differentiation and mineralization in vitro and in vivo (9, 15, 16). On the other hand, two different studies, using rat and human bone formation models, have demonstrated that activin A treatment has a coherent inhibitory influence on osteogenesis leading to significant reduction of the mineralization capacity (11, 17). These opposing effects of activin A on osteoblastogenesis may simply reflect species differences, however, it may be also driven by heterogeneity of the used cell model or the stage of osteoblast differentiation (14). Nevertheless, a negative role of activin A in bone formation is also supported by other in vivo studies in mice and primates in which blockage of activin signaling resulted in increased bone mass (18, 19). Moreover, transgenic mice overexpressing human inhibin A showed increased bone formation (20).The extracellular compartment is crucial for bone because it determines most of the bone quality properties (21, 22), including its strength, stability, and integrity. Interestingly, a mature extracellular matrix (ECM) is characterized by the capacity to mineralize even in the absence of further osteoblast activity (11, 23). This biomineralization process is complex and not fully elucidated but it is thought to be started within MVs (24). Osteoblasts in bone and other cells in mineralization competent tissues, such as cartilage (25), tendon (26), teeth (27), and calcifying vasculature (28) produce and release from their plasma membrane these vesicles with diameters ranging between 50 and 200 nm. It is inside these membrane-enclosed particles that first crystals of mineral are formed and grow, before the vesicle membrane is permeated and the mineral crystallization advances into the ECM (29, 30). In this context, proteins that can mobilize calcium and inorganic phosphate (Pi), the backbone of the hydroxyapatite crystals present in bone, are of utmost importance. P_i donor proteins found in MVs include alkaline phosphatase (ALP) and inorganic pyrophosphatases (31) whereas the annexin family of proteins is postulated to be crucial for calcium influx into the vesicles (32–34).In this study we investigated the inhibitory effect of activin A on human mesenchymal stem cells (hMSC) derived osteoblast differentiation and mineralization. We have previously shown that in human osteoblast cultures activin A influences the expression of many ECM genes altering ECM maturity (11). Thus, we focused our analysis on extracellular environment changes, namely the ECM and matrix vesicles (MVs). The characterization of these compartments was done using the state-of-the-art quantitative proteomics tools including SILAC metabolic labeling and mass spectrometry. Furthermore, the importance of ECM composition for osteoblast differentiation was also determined.     

A new species of Neocarus Chamberlin & Mulaik,?1942 (Opilioacarida,Opilioacaridae) from Brazil,with?remarks?on its postlarval development

Neocarus proteus sp. n., is described from caves and the surrounding epigean environment of ferruginous outcrops (Cangas) in Minas Gerais, Brazil. In addition, some notes about development in this species are presented. Neocarus proteus is the only species in the genus that has smooth or barbed genital setae and that carries coronidia on the basitarsi, tibiae and genua of legs II–III. Females carry additional setae with rounded tips on the subcapitulum, and are, on average, larger than males. This distinct sexual dimorphism appears in the tritonymphal instar and is maintained in the adults.     

Development and validation of an experimental life support system for assessing the effects of global climate change and environmental contamination on estuarine and coastal marine benthic communities

An experimental life support system (ELSS) was constructed to study the interactive effects of multiple stressors on coastal and estuarine benthic communities, specifically perturbations driven by global climate change and anthropogenic environmental contamination. The ELSS allows researchers to control salinity, pH, temperature, ultraviolet radiation (UVR), tidal rhythms and exposure to selected contaminants. Unlike most microcosms previously described, our system enables true independent replication (including randomization). In addition to this, it can be assembled using commercially available materials and equipment, thereby facilitating the replication of identical experimental setups in different geographical locations. Here, we validate the reproducibility and environmental quality of the system by comparing chemical and biological parameters recorded in our ELSS with those prevalent in the natural environment. Water, sediment microbial community and ragworm (the polychaete Hediste diversicolor) samples were obtained from four microcosms after 57 days of operation. In general, average concentrations of dissolved inorganic nutrients (NO₃^?; NH₄⁺ and PO₄^?3) in the water column of the ELSS experimental control units were within the range of concentrations recorded in the natural environment. While some shifts in bacterial community composition were observed between in situ and ELSS sediment samples, the relative abundance of most metabolically active bacterial taxa appeared to be stable. In addition, ELSS operation did not significantly affect survival, oxidative stress and neurological biomarkers of the model organism Hediste diversicolor. The validation data indicate that this system can be used to assess independent or interactive effects of climate change and environmental contamination on benthic communities. Researchers will be able to simulate the effects of these stressors on processes driven by microbial communities, sediment and seawater chemistry and to evaluate potential consequences to sediment toxicity using model organisms such as Hediste diversicolor.     

Mitogenic signaling mediated by oxidants in retinol treated sertoli cells

Recent intervention studies revealed that supplementation with retinoids resulted in a higher incidence of lung cancer. Recently the causal mechanism has begun to be clarified. We report here that retinol-induced oxidative stress is accompanied by cellular proliferation. Retinol (7 μM) significantly induced thiobarbituric acid reactive species (TBARS) formation, which was inhibited by trolox, superoxide dismutase, N-acetylcysteine and ethanol. This was accompanied by an increase in DNA synthesis and focus formation in cultured rat Sertoli cells. Antioxidants and ethanol inhibited retinol-induced DNA synthesis. Our findings suggest that retinol-induced oxidative stress was associated with cellular proliferation complementing our understanding of the significance of retinol supplementation in neoplastic transformation.     

Retinol and retinoic acid increase MMP-2 activity by different pathways in cultured Sertoli cells

Diseases such as atherosclerosis, arthritis and cancer have been related with imbalance in ROS production and failures in regulation of the MMPs. Authors suggested a relationship between MPP activity and ROS. Our research group has demonstrated that retinol 7µM induced changes in Sertoli cell metabolism linking retinol treatment and oxidative stress. We verified MMP activity in Sertoli cells treated with vitamin A using gelatin zymography. We found that retinol (7µM) and retinoic acid (1nM) induced MMP-2 activity in Sertoli cells. Antioxidants reversed retinol-induced but not retinoic acid-induced MMP-2 activity. Moreover, retinol but not retinoic acid increased ROS production quantified by DCFH-DA oxidation. We found that retinol and retinoic acid induced ERK1/2 phosphorylation, but only retinol-increased MMP-2 activity was inhibited by UO126, an ERK1/2 phosphorylation inhibitor. Our findings suggested that retinol-induced MMP-2 activity, but not retinoic acid-induced MMP-2 activity, was related to ERK1/2 phosphorylation and ROS production.     

Global phylogeography of sailfish: deep evolutionary lineages with implications for fisheries management

Hydrobiologia - Since the Miocene profound climatic changes have influenced the biology and ecology of species worldwide, such as their connectivity, genetic population structure, and biogeography....