Antifungal nanofibers made by controlled release of sea animal derived peptide

�� The Royal Society of Chemistry 2015

Pulsed extremely low-frequency magnetic fields stimulate microvesicle release from human monocytic leukaemia cells

Microvesicles are released from cell surfaces constitutively during early apoptosis or upon activation with various stimuli including sublytic membrane attack complex (MAC). This study shows that an alternating current, pulsed, extremely low-frequency electromagnetic field (0.3 ��T at 10 Hz, 6 V AC) induced transient plasma membrane damage that allowed calcium influx. This in turn caused a release of stimulated microvesicles (sMV). When extracellular calcium was chelated with EGTA, sMV biogenesis initiated by ELFMF was markedly reduced and the reduction was less than when the stimulation was the deposition of sublytic MAC. This suggested that pulsed ELFMF resulted in transcellular membrane pores causing organelles to leak additional calcium into the cytoplasm (which EGTA would not chelate) which itself can lead to sMV release.

Heparinized nanohydroxyapatite/collagen granules for controlled release of vancomycin

The purpose of this study was to develop a bone substitute material capable of preventing or treating osteomyelitis through a sustainable release of vancomycin and simultaneously inducing bone regeneration. Porous heparinized nanohydroxyapatite (nanoHA)/collagen granules were characterized using scanning electron microscopy, micro-computed tomography and attenuated total reflectance Fourier transform infrared spectroscopy. After vancomycin adsorption onto the granules, its releasing profile was studied by UV molecular absorption spectroscopy. The heparinized granules presented a more sustainable release over time, in comparison with nonheparinized nanoHA and nanoHA/collagen granules. Vancomycin was released for 360 h and proved to be bioactive until 216 h. Staphylococcus aureus adhesion was higher on granules containing collagen, guiding the bacteria to the material with antibiotic, improving their eradication. Moreover, cytotoxicity of the released vancomycin was assessed using osteoblast cultures, and after 14 days of culture in the presence of vancomycin, cells were able to remain viable, increasing their metabolic activity and colonizing the granules, as observed by scanning electron microscopy and confocal laser scanning microscopy. These findings suggest that heparinized nanoHA/collagen granules are a promising material to improve the treatment of osteomyelitis, as they are capable of releasing vancomycin, eliminating the bacteria, and presented morphological and chemical characteristics to induce bone regeneration.

Da assessoria ao jornalismo : an��lise do processo de produ����o de press release na era digital em Portugal

A presente disserta����o pretende fazer a an��lise do processo de produ����o do press release na assessoria em Portugal, a efic��cia dessa ferramenta de comunica����o junto dos jornalistas e, por iner��ncia, a evolu����o da figura do assessor enquanto profissional reconhecido junto da comunidade jornal��stica. S��o tamb��m objetivos, compreender a relev��ncia de um press release, perceber se gera efeito, analisar a poss��vel forma de melhorar esta ferramenta e, ainda, perceber se esta ferramenta sofreu algum tipo de adapta����o �� era digital. A investiga����o inicia-se com a incurs��o pelos contextos e hist��ria das ��reas profissionais em estudo, a assessoria de comunica����o em ag��ncias e o jornalismo em Portugal, no quadro da crise econ��mica e financeira de 2008 a 2013. O enfoque deste estudo ser�� o procedimento e a efic��cia de um press release, no per��odo considerado. A p��s-produ����o desta ferramenta implica o contacto entre dois interlocutores, os profissionais de assessoria e os profissionais do jornalismo. Finda esta investiga����o com an��lise baseada em seis entrevistas semiestruturadas, divididas em categorias profissionais e setores de atividade: jornalistas, assessores, assessores ex-jornalistas, nas ��reas de sa��de e consumo. Deste estudo resulta que o press release, privilegiando-se a sua estrutura e conte��do, ��, como foi, uma ferramenta fundamental muitas vezes, e nos dias de hoje, no aux��lio ��s negocia����es one to one.

Influence de deux milieux s��quentiels pour la culture d'embryons sur la production d'hormone gonadotrophine chorionique et de progest��rone par des cellules JEG-3 et BeWo [Effects of different embryo development media on hCG and progesterone release by JEG-3 and BeWo cells]

Current in vitro fertilisation (IVF) practice requires synchronisation between the��environment of cultured oocytes and embryos and the surroundings to what they would have��been exposed to in vivo. Commercial, sequential media follow this requirement but their exact��composition is not available. We have compared two widely used IVF culture media systems using��the two choriocarcinoma cell lines JEG-3 and BeWo. The two hormones hCG and progesterone��were determined in the culture supernatants as endpoints. In both cell lines, but in a more��pronounced way in JEG-3, progesterone rather than hCG production was stimulated, and a��higher hormone release was observed in the fertilisation than in the cleavage media. Differences��between manufacturers were small and did not favour one system over the other. We conclude��that both sequential media systems can be equally well used in current IVF laboratory practice.���� 2012 Elsevier Masson SAS. All rights reserved.

D-amphetamine fails to increase extracellular dopamine levels in mice lacking alpha 1b-adrenergic receptors: relationship between functional and nonfunctional dopamine release.

It was found recently that locomotor and rewarding effects of psychostimulants and opiates were dramatically decreased or suppressed in mice lacking alpha1b-adrenergic receptors [alpha1b-adrenergic receptor knock-outs (alpha1bAR-KOs)] (Drouin et al., 2002). Here we show that blunted locomotor responses induced by 3 and 6 mg/kg d-amphetamine in alpha1bAR-KO mice [-84 and -74%, respectively, when compared with wild-type (WT) mice] are correlated with an absence of d-amphetamine-induced increase in extracellular dopamine (DA) levels in the nucleus accumbens of alpha1bAR-KO mice. Moreover, basal extracellular DA levels in the nucleus accumbens are lower in alpha1bAR-KO than in WT littermates (-28%; p < 0.001). In rats however, prazosin, an alpha1-adrenergic antagonist, decreases d-amphetamine-induced locomotor hyperactivity without affecting extracellular DA levels in the nucleus accumbens, a finding related to the presence of an important nonfunctional release of DA (Darracq et al., 1998). We show here that local d-amphetamine releases nonfunctional DA with the same affinity but a more than threefold lower amplitude in C57BL6/J mice than in Sprague Dawley rats. Altogether, this suggests that a trans-synaptic mechanism amplifies functional DA into nonfunctional DA release. Our data confirm the presence of a powerful coupling between noradrenergic and dopaminergic neurons through the stimulation of alpha1b-adrenergic receptors and indicate that nonfunctional DA release is critical in the interpretation of changes in extracellular DA levels. These results suggest that alpha1b-adrenergic receptors may be important therapeutic pharmacological targets not only in addiction but also in psychosis because most neuroleptics possess anti-alpha1-adrenergic properties.

In vivo and in vitro effects of somatostatin and insulin on glucagon release in a human glucagonoma.

Inhibition of pancreatic glucagon secretion has been reported to be mediated by glucose, insulin and somatostatin. As no human pancreatic alpha-cell lines are available to study in vitro the relative importance of insulin and glucose in the control of pancreatic glucagon release, we investigated a patient presenting with a malignant glucagonoma who underwent surgical resection of the tumour. Functional somatostatin receptors were present as octreotide administration decreased basal glucagon and insulin secretion by 52 and 74%, respectively. The removed tumour was immunohistochemically positive for glucagon, chromogranin A and pancreatic polypeptide but negative for insulin, gastrin and somatostatin. The glucagonoma cells were also isolated and cultured in vitro. Incubation experiments revealed that change from high (10 mM) to low (1 mM) glucose concentration was unable to stimulate glucagon secretion. A dose-dependent inhibition of glucagon release by insulin was however, observed at low glucose concentration. These findings demonstrate that insulin could inhibit glucagon secretion in vitro in the absence of elevated glucose concentrations. These data suggest, as observed in vivo and in vitro in several animal studies, that glucopenia-induced glucagon secretion in humans is not mediated by a direct effect of low glucose on alpha-cells but possibly by a reduction of insulin-mediated alpha-cell suppression and/or an indirect neuronal stimulation of glucagon release.

Etude des propri��t��s dynamiques de la s��cr��tion r��gul��e des v��sicules glutamatergiques des astrocytes

RESUME GRAND PUBLICLe cerveau est compos�� de diff��rents types cellulaires, dont les neurones et les astrocytes. Faute de moyens pour les observer, les astrocytes sont tr��s longtemps rest��s dans l'ombre alors que les neurones, b��n��ficiant des outils ad hoc pour ��tre stimul��s et ��tudi��s, ont fait l'objet de toutes les attentions. Le d��veloppement de l'imagerie cellulaire et des outils fluorescents ont permis d'observer ces cellules non ��lectriquement excitables et d'obtenir des informations qui laissent penser que ces cellules sont loin d'��tre passives et participent activement au fonctionnement c��r��bral. Cette participation au fonctionnement c��r��bral se fait en partie par le biais de la lib��ration de substances neuro-actives (appell��es gliotransmetteurs) que les astrocytes lib��rent �� proximit�� des synapses permettant ainsi de moduler le fonctionnement neuronal. Cette lib��ration de gliotransmetteurs est principalement caus��e par l'activit�� neuronale que les astrocytes sont capables de sentir. N��anmoins, nous savons encore peu de chose sur les propri��t��s pr��cises de la lib��ration des gliotransmetteurs. Comprendre les propri��t��s spatio-temporelles de cette lib��ration est essentiel pour comprendre le mode de communication de ces cellules et leur implication dans la transmission de l'information c��r��brale. En utilisant des outils fluorescents r��cemment d��velopp��s et en combinant diff��rentes techniques d'imagerie cellulaire, nous avons pu obtenir des informations tr��s pr��cises sur la lib��ration de ces gliotransmetteurs par les astrocytes. Nous avons ainsi confirm�� que cette lib��ration ��tait un processus tr��s rapide et qu'elle ��tait contr��l��e par des augmentations de calcium locales et rapides. Nous avons ��galement d��crit une organisation complexe de la machinerie supportant la lib��ration des gliotransmetteurs. Cette organisation complexe semble ��tre �� la base de la lib��ration extr��mement rapide des gliotransmetteurs. Cette rapidit�� de lib��ration et cette complexit�� structurelle semblent indiquer que les astrocytes sont des cellules particuli��rement adapt��es �� une communication rapide et qu'elles peuvent, au m��me titre que les neurones dont elles seraient les partenaires l��gitimes, participer �� la transmission et �� l'int��gration de l'information c��r��brale.RESUMEDe petites v��sicules, les �� SLMVs �� ou �� Synaptic Like MicroVesicles ��, exprimant des transporteurs v��siculaires du glutamate (VGluTs) et lib��rant du glutamate par exocytose r��gul��e, ont r��cemment ��t�� d��crites dans les astrocytes en culture et in situ. N��anmoins, nous savons peu de chose sur les propri��t��s pr��cises de la s��cr��tion de ces SLMVs. Contrairement aux neurones, le couplage stimuluss��cr��tion des astrocytes n'est pas bas�� sur l'ouverture des canaux calciques membranaires mais n��cessite l'intervention de seconds messagers et la lib��ration du calcium par le reticulum endoplasmique (RE). Comprendre les propri��t��s spatio-temporelles de la s��cr��tion astrocytaire est essentiel pour comprendre le mode de communication de ces cellules et leur implication dans la transmission de l'information c��r��brale. Nous avons utilis�� des outils fluorescents r��cemment d��velopp��s pour ��tudier le recyclage des v��sicules synaptiques glutamatergiques comme les colorants styryles et la pHluorin afin de pouvoir suivre la s��cr��tion des SLMVs �� l'��chelle de la cellule mais ��galement �� l'��chelle des ��v��nements. L'utilisation combin��e de l'��pifluorescence et de la fluorescence �� onde ��vanescente nous a permis d'obtenir une r��solution temporelle et spatiale sans pr��c��dent. Ainsi avons-nous confirm�� que la s��cr��tion r��gul��e des astrocytes ��tait un processus tr��s rapide (de l'ordre de quelques centaines de millisecondes). Nous avons d��couvert que cette s��cr��tion est contr��l��e par des augmentations de calcium locales et rapides. Nous avons ��galement d��crit des compartiments cytosoliques d��limit��s par le RE �� proximit�� de la membrane plasmique et contenant les SLMVs. Cette organisation semble ��tre �� la base du couplage rapide entre l'activation des GPCRs et la s��cr��tion. L'existence de compartiments subcellulaires ind��pendants permettant de contenir les messagers intracellulaires et de limiter leur diffusion semble compenser de mani��re efficace la nonexcitabilit�� ��lectrique des astrocytes. Par ailleurs, l'existence des diff��rents pools de v��sicules recrut��s s��quentiellement et fusionnant selon des modalit��s distinctes ainsi que l'existence de m��canismes permettant le renouvellement de ces pools lors de la stimulation sugg��rent que les astrocytes peuvent faire face �� une stimulation soutenue de leur s��cr��tion. Ces donn��es sugg��rent que la lib��ration de gliotransmetteurs par exocytose r��gul��e n'est pas seulement une propri��t�� des astrocytes en culture mais bien le r��sultat d'une forte sp��cialisation de ces cellules pour la s��cr��tion. La rapidit�� de cette s��cr��tion donne aux astrocytes toutes les comp��tences pour pouvoir intervenir de mani��re active dans la transmission et l'int��gration de l'information.ABSTRACTRecently, astrocytic synaptic like microvesicles (SLMVs), that express vesicular glutamate transporters (VGluTs) and are able to release glutamate by Ca2+-dependent regulated exocytosis, have been described both in tissue and in cultured astrocytes. Nevertheless, little is known about the specific properties of regulated secretion in astrocytes. Important differences may exist between astrocytic and neuronal exocytosis, starting from the fact that stimulus-secretion coupling in astrocytes is voltage independent, mediated by G-protein-coupled receptors and the release of Ca2+ from internal stores. Elucidating the spatiotemporal properties of astrocytic exo-endocytosis is, therefore, of primary importance for understanding the mode of communication of these cells and their role in brain signaling. We took advantage of fluorescent tools recently developed for studying recycling of glutamatergic vesicles at synapses like styryl dyes and pHluorin in order to follow exocytosis and endocytosis of SLMVs at the level of the entire cell or at the level of single event. We combined epifluorescence and total internal reflection fluorescence imaging to investigate, with unprecedented temporal and spatial resolution, the events underlying the stimulus-secretion in astrocytes. We confirmed that exo-endocytosis process in astrocytes proceeds with a time course on the millisecond time scale. We discovered that SLMVs exocytosis is controlled by local and fast Ca2+ elevations; indeed submicrometer cytosolic compartments delimited by endoplasmic reticulum (ER) tubuli reaching beneath the plasma membrane and containing SLMVs. Such complex organization seems to support the fast stimulus-secretion coupling reported here. Independent subcellular compartments formed by ER, SLMVs and plasma membrane containing intracellular messengers and limiting their diffusion seem to compensate efficiently the non-electrical excitability of astrocytes. Moreover, the existence of two pools of SLMVs which are sequentially recruited suggests a compensatory mechanisms allowing the refill of SLMVs and supporting exocytosis process over a wide range of multiple stimuli. These data suggest that regulated secretion is not only a feature of cultured astrocytes but results from a strong specialization of these cells. The rapidity of secretion demonstrates that astrocytes are able to actively participate in brain information transmission and processing.

T-type Ca2+ channels, SK2 channels and SERCAs gate sleep-related oscillations in thalamic dendrites.

T-type Ca2+ channels (T channels) underlie rhythmic burst discharges during neuronal oscillations that are typical during sleep. However, the Ca2+-dependent effectors that are selectively regulated by T currents remain unknown. We found that, in dendrites of nucleus reticularis thalami (nRt), intracellular Ca2+ concentration increases were dominated by Ca2+ influx through T channels and shaped rhythmic bursting via competition between Ca2+-dependent small-conductance (SK)-type K+ channels and Ca2+ uptake pumps. Oscillatory bursting was initiated via selective activation of dendritically located SK2 channels, whereas Ca2+ sequestration by sarco/endoplasmic reticulum Ca2+-ATPases (SERCAs) and cumulative T channel inactivation dampened oscillations. Sk2-/- (also known as Kcnn2) mice lacked cellular oscillations, showed a greater than threefold reduction in low-frequency rhythms in the electroencephalogram of non-rapid-eye-movement sleep and had disrupted sleep. Thus, the interplay of T channels, SK2 channels and SERCAs in nRt dendrites comprises a specialized Ca2+ signaling triad to regulate oscillatory dynamics related to sleep.

Nanocarriers for DNA Vaccines: Co-Delivery of TLR-9 and NLR-2 Ligands Leads to Synergistic Enhancement of Proinflammatory Cytokine Release

Adjuvants enhance immunogenicity of vaccines through either targeted antigen delivery or stimulation of immune receptors. Three cationic nanoparticle formulations were evaluated for their potential as carriers for a DNA vaccine, and muramyl dipeptide (MDP) as immunostimulatory agent, to induce and increase immunogenicity of Mycobacterium tuberculosis antigen encoding plasmid DNA (pDNA). The formulations included (1) trimethyl chitosan (TMC) nanoparticles, (2) a squalene-in-water nanoemulsion, and (3) a mineral oil-in-water nanoemulsion. The adjuvant effect of the pDNA-nanocomplexes was evaluated by serum antibody analysis in immunized mice. All three carriers display a strong adjuvant effect, however, only TMC nanoparticles were capable to bias immune responses towards Th1. pDNA naturally contains immunostimulatory unmethylated CpG motifs that are recognized by Toll-like receptor 9 (TLR-9). In mechanistic in vitro studies, activation of TLR-9 and the ability to enhance immunogenicity by simultaneously targeting TLR-9 and NOD-like receptor 2 (NLR-2) was determined by proinflammatory cytokine release in RAW264.7 macrophages. pDNA in combination with MDP was shown to significantly increase proinflammatory cytokine release in a synergistic manner, dependent on NLR-2 activation. In summary, novel pDNA-Ag85A loaded nanoparticle formulations, which induce antigen specific immune responses in mice were developed, taking advantage of the synergistic combinations of TLR and NLR agonists to increase the adjuvanticity of the carriers used.

Idiosyncratic volatility around information release date

Several papers document idiosyncratic volatility is time-varying and many attempts have been made to reveal whether idiosyncratic risk is priced. This research studies behavior of idiosyncratic volatility around information release dates and also its relation with return after public announcement. The results indicate that when a company discloses specific information to the market, firm���s specific volatility level shifts and short-horizon event-induced volatility vary significantly however, the category to which the announcement belongs is not important in magnitude of change. This event-induced volatility is not small in size and should not be downplayed in event studies. Moreover, this study shows stocks with higher contemporaneous realized idiosyncratic volatility earn lower return after public announcement consistent with ���divergence of opinion hypothesis���. While no significant relation is found between EGARCH estimated idiosyncratic volatility and return and also between one-month lagged idiosyncratic volatility and return presumably due to significant jump around public announcement both may provide some signals regarding future idiosyncratic volatility through their correlations with contemporaneous realized idiosyncratic volatility. Finally, the study show that positive relation between return and idiosyncratic volatility based on under-diversification is inadequate to explain all different scenarios and this negative relation after public announcement may provide a useful trading rule.

A possible role for intrinsic calcium buffers in the long- term adaptation of crayfish neurons

Increasing the impulse activity of neurons in vivo over 3 or more days causes a reduction in transmitter release that persists for days or weeks (eg. Mercier and Atwood, 1989). This effect is usually accompanied by decreased synaptic fatigue. These two changes involve presynaptic mechanisms and indicate "long-term adaptation" (LTA) of nerve terminals. Previous experiments have shown that LTA requires extracellular calcium and protein synthesis (eg. Hong and Lnenicka, Soc. Neurosci. Abstr. 17:1322) and appears to involve communication between the cell body and the nerve terminals. The present study examines the possibility that the reduction in transmitter release is caused by an -increase in the calcium buffering ability within the nerve terminals. It examines the responses of adapted and control nerve terminals to exogenously applied calcium buffer, BAPTA-AM, which decreases transmitter release (Robitialle and Charlton, 1992). If LTA increases intrinsic Ca2+-buffering, the membrane permeant form of BAPTA should have less effect on adapted nerve terminals than on controls. Experiments are performed on the phasic abdominal extensor motor neurons of the crayfish, Procambarns clarkii. BAPTA-AM decreases excitatory postsynaptic potentials (EPSP's) of the phasic extensor muscles in a dosedependent manner between 5 and 50 JLM. LTA is elicited by in vivo stimulation at 2.5 Hz for 2-4 h per day over 3 days, which reduces EPSP's by over 50%. Experiments indicate that BAPTA-AM produces no significant change in EPSP reduction in adapted neurons when compared to controls. These results do not support the hypothesis that increased daily activity alters rapid intrinsic calcium buffers, that are able to reduce transmitter output in the same manner as BAPTA.

Alli��nce Media Release - June 6, 1995

A media release from Inniskillin Wines announcing the launch of "Alli��nce", a joint winemaking venture between Inniskillin and Jaffelin Wines of France.

Draft News Release - Great Lakes Water Quality Agreement

A News Release draft to be sent to "100 newspapers, radio and television stations (virtually all those with offices within 20 miles of the Lakes), make them available to the Press Gallery, special interest groups, trade publication and Mayors etc. of Great Lake-side communities". The release discusses the need for an upgrade to "the 1972 Canada-U.S. Great Lakes Water Quality agreement". Within the document, O'Sullivan is quoted that the agreement "should be upgraded to become a treaty with the United States, so that after all the effort which has already been put into tyring to clean up the Great Lakes we the provision which provides for cancellation by either party giving twelve months (notice) to do so". The total report is 61 pages in length.