Derivatization Does Not Influence Antimicrobial and Antifungal Activities of Applanoxidic Acids and Sterols from Ganoderma spp.

Abstract Applanoxidic acids and sterols, isolated from Ganoderma spp., were acetylated and/or methylated. The antibacterial activity against Escherichia coli and Staphylococcus aureus and the antifungal activity against Candida albicans and Trichophyton mentagrophytes of the derivatives were investigated by a microdilution method, and compared with those of the natural products. Both natural and modified compounds exhibited comparable antibacterial and antifungal activities in a range of 1.0 to > 2.0 mg/ml minimal inhibitory concentratio

Catching what we can't see: manual interception of occluded fly-ball trajectories

Control of interceptive actions may involve fine interplay between feedback-based and predictive mechanisms. These processes rely heavily on target motion information available when the target is visible. However, short-term visual memory signals as well as implicit knowledge about the environment may also contribute to elaborate a predictive representation of the target trajectory, especially when visual feedback is partially unavailable because other objects occlude the visual target. To determine how different processes and information sources are integrated in the control of the interceptive action, we manipulated a computer-generated visual environment representing a baseball game. Twenty-four subjects intercepted fly-ball trajectories by moving a mouse cursor and by indicating the interception with a button press. In two separate sessions, fly-ball trajectories were either fully visible or occluded for 750, 1000 or 1250 ms before ball landing. Natural ball motion was perturbed during the descending trajectory with effects of either weightlessness (0 g) or increased gravity (2 g) at times such that, for occluded trajectories, 500 ms of perturbed motion were visible before ball disappearance. To examine the contribution of previous visual experience with the perturbed trajectories to the interception of invisible targets, the order of visible and occluded sessions was permuted among subjects. Under these experimental conditions, we showed that, with fully visible targets, subjects combined servo-control and predictive strategies. Instead, when intercepting occluded targets, subjects relied mostly on predictive mechanisms based, however, on different type of information depending on previous visual experience. In fact, subjects without prior experience of the perturbed trajectories showed interceptive errors consistent with predictive estimates of the ball trajectory based on a-priori knowledge of gravity. Conversely, the interceptive responses of subjects previously exposed to fully visible trajectories were compatible with the fact that implicit knowledge of the perturbed motion was also taken into account for the extrapolation of occluded trajectories

Rhythmic tapping to a moving beat motion kinematics overrules natural gravity

beat induction is the cognitive ability that allows humans to listen to a regular pulse in music and move in synchrony with it. although auditory rhythmic cues induce more consistent synchronization than flashing visual metronomes, this auditory-visual asymmetry can be canceled by visual moving stimuli. here, we investigated whether the naturalness of visual motion or its kinematics could provide a synchronization advantage over flashing metronomes. Subjects were asked to tap in sync with visual metronomes defined by vertically accelerating/decelerating motion, either congruent or not with natural gravity; horizontally accelerating/decelerating motion; or flashing stimuli. we found that motion kinematics was the predominant factor determining rhythm synchronization, as accelerating moving metronomes in any cardinal direction produced more precise and predictive tapping than decelerating or flashing conditions. our results support the notion that accelerating visual metronomes convey a strong sense of beat, as seen in the cueing movements of an orchestra director

Regenerative potential of DPSCs and revascularization. direct, paracrine or autocrine effect?

A new source of mesenchymal stem cells has recently been discovered, the so-called dental pulp derived stem cells (DPSCs) which therefore could represent potentially tools for regenerative medicine. DPSC originate from the neural crest and are physiologically involved in dentin homeostasis; moreover, they contribute to bone remodeling and differentiation into several tissues including cartilage, bone, adipose and nervous tissues. DPSCs have also been shown to influence the angiogenesis process, for example through the release of secretory factors or by differentiating into vascular and/or perivascular cells. Angiogenesis, that has a pivotal role in tissue regeneration and repair, is defined as the formation of new vessels from preexisting vessels and is mediated by mutual and reciprocal interactions between endothelial cells and perivascular cells. It is also known that co-cultures of perivascular and endothelial cells (ECs) can form a vascular network in vitro and also in vivo. Since DPSCs seem to have characteristics similar to pericytes, understanding the possible mechanism of interaction between DPSCs and ECs during neo-angiogenesis is dramatically important for the development of advanced clinical application in the field of regeneration. Graphical abstract: [Figure not available: see fulltext.

Interception of vertically approaching objects: temporal recruitment of the internal model of gravity and contribution of optical information

introduction: recent views posit that precise control of the interceptive timing can be achieved by combining on-line processing of visual information with predictions based on prior experience. Indeed, for interception of free-falling objects under gravity's effects, experimental evidence shows that time-to-contact predictions can be derived from an internal gravity representation in the vestibular cortex. however, whether the internal gravity model is fully engaged at the target motion outset or reinforced by visual motion processing at later stages of motion is not yet clear. moreover, there is no conclusive evidence about the relative contribution of internalized gravity and optical information in determining the time-to-contact estimates.methods: we sought to gain insight on this issue by asking 32 participants to intercept free falling objects approaching directly from above in virtual reality. object motion had durations comprised between 800 and 1100 ms and it could be either congruent with gravity (1 g accelerated motion) or not (constant velocity or -1 g decelerated motion). we analyzed accuracy and precision of the interceptive responses, and fitted them to bayesian regression models, which included predictors related to the recruitment of a priori gravity information at different times during the target motion, as well as based on available optical information.results: consistent with the use of internalized gravity information, interception accuracy and precision were significantly higher with 1 g motion. moreover, bayesian regression indicated that interceptive responses were predicted very closely by assuming engagement of the gravity prior 450 ms after the motion onset, and that adding a predictor related to on-line processing of optical information improved only slightly the model predictive power. discussion: thus, engagement of a priori gravity information depended critically on the processing of the first 450 ms of visual motion information, exerting a predominant influence on the interceptive timing, compared to continuously available optical information. finally, these results may support a parallel processing scheme for the control of interceptive timing

New 3,4-seco-ent-kaurene dimers from Croton micans.

From the stems of Croton micans Sw., five new 3,4- seco-ent-kaurene dimers: micansinoic acid (1), isomicansinoic acid (2), and the dimethyl (3), monomethyl (4) and monoethyl ester (5) of micansinoic acid were isolated. The structures of the new compounds were elucidated by spectroscopic data interpretation, mainly 1D and 2D NMR experiments and MS. These compounds are the first 3,4- seco-ent-kaurene dimers from a Croton species

Elevated alanine aminotransferase in blood donors: role of different factors and multiple viral infections.

Many different aetiological agents stimulate alanine aminotransferase (ALT) production. Viral markers and other aetiologies were investigated in 2166 individuals, randomly selected from 10 000 consecutive blood donors. Elevation of ALT was found in 10.8% of subjects. Grouping donors according to ALT level and correlating with, respectively, hepatitis B core antibody (HBcAb), cytomegalovirus antibody alone, or associated with HBcAb, showed similar findings (high ALT 11.1%, normal 11.6%; high 85.4%, normal 81.4%; high 10.2%, normal 11.0%, respectively). Hepatitis C virus (HCV) antibody was found to be significantly associated with elevated ALT levels (high 1.7%, normal 0.26%). Other causes of ALT elevation were alcohol abuse (17%), obesity (25%) and dyslipidaemia (38%), but in 11% there was no obvious aetiology. Although HCV is a rare cause of elevated ALT in blood donors, it seems to be the only virus, among those tested, to account for liver damage. This may be due to the non-protective role of HCV antibody, the low specificity of ALT, or the pathogenic role of uninvestigated viruses

Three new triterpenes from the resinous bark of Protium kleinii and their antinociceptive activity

Three novel pentacyclic triterpenes have been isolated from the resin of Protium kleinii and their structures elucidated by NMR spectroscopy as 3-oxo-11beta,16beta-dihydroxy-urs-12-ene (1), 3-oxo-11beta-hydroxy-urs-12-ene (2) and 3-oxo-11beta-hydroxy-olean-12-ene (3). The systemic administration of the above compounds (10-100 mg kg-1, i.p.) was able to inhibited both first and second phase of the formalin-induced nociception in mice. The known triterpenes 3beta,16beta-dihydroxy-olean-12-ene (brein) (4) and a mixture of alpha (5)- and beta-amyrin (6) were also found. Três triterpenos pentacíclicos inéditos foram isolados da resina de Protium kleinii. Suas estruturas, 3-oxo-11beta,16beta-diidróxi-urs-12-eno (1), 3-oxo-11beta-hidróxi-urs-12-eno (2) e 3-oxo-11beta-hidróxi-olean-12-eno (3), foram elucidadas por espectroscopia de RMN. A administração sistêmica destes compostos (10-100 mg kg-1, i.p.) foi capaz de inibir tanto a primeira quanto a segunda fase da nocicepção induzida pela formalina em camundongos. Em adição, foram isolados os triterpenos conhecidos 3beta,16beta-dihidróxi-urs-12-eno (breina) (4) e uma mistura de alfa (5)- e beta-amirina (6)

Challenges in Developing Better Observational Constraints and Models for Aerosols : Emerging Ideas for Design and Use of Future Observing Systems

No abstract availabl