The CB1 cannabinoid receptor mediates excitotoxicity-induced neural progenitor proliferation and neurogenesis

Endocannabinoids are lipid signaling mediators that exert an important neuromodulatory role and confer neuroprotection in several types of brain injury. Excitotoxicity and stroke can induce neural progenitor (NP) proliferation and differentiation as an attempt of neuroregeneration after damage. Here we investigated the mechanism of hippocampal progenitor cell engagement upon excitotoxicity induced by kainic acid administration and the putative involvement of the CB1 cannabinoid receptor in this process. Adult NPs express kainate receptors that mediate proliferation and neurosphere generation in vitro via CB1 cannabinoid receptors. Similarly, in vivo studies showed that excitotoxicity-induced hippocampal NPs proliferation and neurogenesis are abrogated in CB1-deficient mice and in wild-type mice administered with the selective CB1 antagonist rimonabant (N-piperidino-5-(4-chlorophenyl)-1-(2,4-dichlorophenyl)-4-methyl-3-pyrazolecarboxamide; SR141716). Kainate stimulation increased basic fibroblast growth factor (bFGF) expression in cultured NPs in a CB1-dependent manner as this response was prevented by rimonabant and mimicked by endocannabinoids. Likewise, in vivo analyses showed that increased hippocampal expression of bFGF, as well as of brain-derived neurotrophic factor and epidermal growth factor, occurs upon excitotoxicity and that CB1 receptor ablation prevents this induction. Moreover, excitotoxicity increased the number of CB1+ bFGF+ cells, and this up-regulation preceded NP proliferation. In summary, our results show the involvement of the CB1 cannabinoid receptor in NP proliferation and neurogenesis induced by excitotoxic injury and support a role for bFGF signaling in this process.     

The role of phosphoinositide 3-kinase C2alpha in insulin signaling

The members of the class II phosphoinositide 3-kinase (PI3K) family can be activated by several stimuli, indicating that these enzymes can regulate many intracellular processes. Nevertheless, to date, there has been no definitive identification of their in vivo product, their mechanism(s) of activation, or their precise intracellular roles. By metabolic labeling, we here identify phosphatidylinositol 3-phosphate as the sole in vivo product of the insulin-dependent activation of PI3K-C2alpha, confirming the emerging role of such a phosphoinositide in signaling. We demonstrate that activation of PI3K-C2alpha involves its recruitment to the plasma membrane and that activation is mediated by the GTPase TC10. This is the first report showing a membrane targeting-mediated mechanism of activation for PI3K-C2alpha and that a small GTP-binding protein can activate a class II PI3K isoform. We also demonstrate that PI3K-C2alpha contributes to maximal insulin-induced translocation of the glucose transporter GLUT4 to the plasma membrane and subsequent glucose uptake, definitely assessing the role of this enzyme in insulin signaling.     

Potential of agroindustrial waste from olive oil industry for fuel ethanol production

Olive pulp (OP) is a highly polluting semi-solid residue generated from the two-stage extraction processing of olives and is a major environmental issue in Southern Europe, where 80% of the world olive oil is produced. At present, OP is either discarded to the environment or combusted with low calorific value. In this work, utilization of OP as a potential substrate for production of bioethanol was studied. Enzymatic hydrolysis and subsequent glucose fermentation by baker's yeast were evaluated for OP from 10% to 30% dry matter (i.e., undiluted). Enzymatic hydrolysis resulted in an increase in glucose concentration by 75%, giving final glucose yields near 70%. Fermentation of undiluted OP hydrolysate (OPH) resulted in the maximum ethanol produced (11.2 g/L) with productivity of 2.1 g/L/h. Ethanol yields were similar for all tested OPH concentrations and were in the range of 0.49-0.51 g/g. Results showed that yeast could effectively ferment OPH even without nutrient addition, revealing the tolerance of yeast to OP toxicity. Because of low xylan (12.4%) and glucan (16%) content in OP, this specific type of OP is not a suitable material for producing only ethanol and thus, bioethanol production should be integrated with production of other value-added products.     

The importance of human FcgammaRI in mediating protection to malaria

The success of passive immunization suggests that antibody-based therapies will be effective at controlling malaria. We describe the development of fully human antibodies specific for Plasmodium falciparum by antibody repertoire cloning from phage display libraries generated from immune Gambian adults. Although these novel reagents bind with strong affinity to malaria parasites, it remains unclear if in vitro assays are predictive of functional immunity in humans, due to the lack of suitable animal models permissive for P. falciparum. A potentially useful solution described herein allows the antimalarial efficacy of human antibodies to be determined using rodent malaria parasites transgenic for P. falciparum antigens in mice also transgenic for human Fc-receptors. These human IgG1s cured animals of an otherwise lethal malaria infection, and protection was crucially dependent on human FcgammaRI. This important finding documents the capacity of FcgammaRI to mediate potent antimalaria immunity and supports the development of FcgammaRI-directed therapy for human malaria.     

Calcium supplements in healthy children do not affect weight gain, height, or body composition

Objective: Calcium intake is a potential factor influencing weight gain and may reduce body weight, but the evidence for this in children is conflicting. The aim of this study was to use data from randomized controlled trials to determine whether calcium supplementation in healthy children affects weight or body composition. Research Methods and Procedures: This study is a systematic review. We identified potential studies by searching the following electronic bibliographic databases: CENTRAL, MEDLINE, EMBASE, CINAHL, AMED, MANTIS, ISI Web of Science, Food Science and Technology Abstracts, and Human Nutrition up until April 1, 2005 and hand‐searched relevant conference abstracts. Studies were included if they were placebo‐controlled randomized controlled trials of calcium supplementation, with at least 3 months of supplementation, in healthy children and with outcome measures including weight. Meta‐analyses were performed using fixed effects models and weighted mean differences for weight and height and standardized mean differences (SMDs) for body composition measures. Results: There were no statistically significant effects of calcium supplementation on weight [+0.14 kg; 95% confidence interval (CI), ?0.28, +0.57 kg], height (+0.22 cm; 95% CI, ?0.30, +0.74 cm), body fat (SMD, +0.04; 95% CI, ?0.08, +0.15), or lean mass (SMD, +0.14; 95% CI, ?0.03, +0.31). Discussion: There is no evidence to support the use of calcium supplementation as a public health intervention to reduce weight gain or body fat in healthy children. Although our results do not rule out an effect of dietary supplementation with dairy products on weight gain or body composition, there is little evidence to support this hypothesis.     

Temporal effects of ocean warming and acidification on coral–algal competition

Coral Reefs - While there is an ever-expanding list of impacts on coral reefs as a result of ocean warming and acidification, there is little information on how these global changes influence...     

Deletions at the SOX10 gene locus cause Waardenburg syndrome types 2 and 4

Waardenburg syndrome (WS) is an auditory-pigmentary disorder that exhibits varying combinations of sensorineural hearing loss and abnormal pigmentation of the hair and skin. Depending on additional symptoms, WS is classified into four subtypes, WS1-WS4. Absence of additional features characterizes WS2. The association of facial dysmorphic features defines WS1 and WS3, whereas the association with Hirschsprung disease (aganglionic megacolon) characterizes WS4, also called "Waardenburg-Hirschsprung disease." Mutations within the genes MITF and SNAI2 have been identified in WS2, whereas mutations of EDN3, EDNRB, and SOX10 have been observed in patients with WS4. However, not all cases are explained at the molecular level, which raises the possibility that other genes are involved or that some mutations within the known genes are not detected by commonly used genotyping methods. We used a combination of semiquantitative fluorescent multiplex polymerase chain reaction and fluorescent in situ hybridization to search for SOX10 heterozygous deletions. We describe the first characterization of SOX10 deletions in patients presenting with WS4. We also found SOX10 deletions in WS2 cases, making SOX10 a new gene of WS2. Interestingly, neurological phenotypes reminiscent of that observed in WS4 (PCWH syndrome [peripheral demyelinating neuropathy, central dysmyelinating leukodystrophy, WS, and Hirschsprung disease]) were observed in some WS2-affected patients with SOX10 deletions. This study further characterizes the molecular complexity and the close relationship that links the different subtypes of WS.     

Aspects of Male Competition in <Emphasis Type="Italic">Colobus vellerosus</Emphasis>: Preliminary Data on Male and Female Loud Calling,and Infant Deaths After a Takeover

Male Colobus vellerosus are the main participants in intergroup encounters, and lead incursions in neighboring groups during which they attack infants. Extragroup copulations, all-male groups, and male takeover occur in the species. Here, we provide additional information on behaviors associated with male reproductive competition in Colobus vellerosus. We examined 1 resident male loud calling and participation in intergroup encounters in relation to a takeover. We also report a second case of takeover that led to the death of the former resident male and the death of 2 male infants, presumably as a result of aggression from the all-male group. The new resident male wounded the third infant of the group, which apparently died after its mother abandoned it. During the period characterized by the attacks on the infant and after its disappearance, females initiated and participated in loud call bouts with the new resident male. We examine the possible functions of female loud calling, and suggest that in this context, it might force the resident male to call along to indicate his presence.     

Functional cell permeable motifs within medically relevant proteins

Increasing experimental evidence indicates that short polybasic peptides are able to translocate across the membrane of living cells. However, these peptides, often derived from viruses and insects, may induce unspecific effects that could mask the action of their cargoes. Here, we show that a panel of lysine and/or arginine-rich peptides, derived from human proteins involved in cell signalling pathways leading to inflammation, possess the intrinsic ability to cross intact cellular membranes. These peptides are also capable of carrying a biologically active cargo. One of these peptides, encompassing the cell permeable sequence of the Toll-receptor 4 (TLR4) adaptor protein (TIRAP) and modified to carry a dominant-negative domain of the same TIRAP protein, selectively inhibited the production of pro-inflammatory cytokines upon LPS challenge, in in vitro, ex vivo and in vivo experiments. Docking studies indicated that this inhibition might be mediated by the disruption of the recruitment of downstream effector molecules. These results show for the first time the potential of using for therapy cell permeable peptides derived from human proteins involved in disease.