The Psychedelic State Induced By Ayahuasca Modulates The Activity And Connectivity Of The Default Mode Network.

The experiences induced by psychedelics share a wide variety of subjective features, related to the complex changes in perception and cognition induced by this class of drugs. A remarkable increase in introspection is at the core of these altered states of consciousness. Self-oriented mental activity has been consistently linked to the Default Mode Network (DMN), a set of brain regions more active during rest than during the execution of a goal-directed task. Here we used fMRI technique to inspect the DMN during the psychedelic state induced by Ayahuasca in ten experienced subjects. Ayahuasca is a potion traditionally used by Amazonian Amerindians composed by a mixture of compounds that increase monoaminergic transmission. In particular, we examined whether Ayahuasca changes the activity and connectivity of the DMN and the connection between the DMN and the task-positive network (TPN). Ayahuasca caused a significant decrease in activity through most parts of the DMN, including its most consistent hubs: the Posterior Cingulate Cortex (PCC)/Precuneus and the medial Prefrontal Cortex (mPFC). Functional connectivity within the PCC/Precuneus decreased after Ayahuasca intake. No significant change was observed in the DMN-TPN orthogonality. Altogether, our results support the notion that the altered state of consciousness induced by Ayahuasca, like those induced by psilocybin (another serotonergic psychedelic), meditation and sleep, is linked to the modulation of the activity and the connectivity of the DMN.

Evaluation of the Incidence of Bladder Perforation After Transurethral Bladder Tumor Resection in a Residency Setting

Purpose: To evaluate prospectively the actual bladder perforation incidence during transurethral resection of bladder tumor (TURB) performed by residents and to identify possible predisposing factors to such condition. Patients and Methods: Thirty-four patients with bladder tumor were submitted to TURB in our academic institution in April 2006, and were prospectively studied. Procedures were all done by senior residents under an attending direct supervision. All patients had a cystograms performed after the procedure by the injection of 400 mL of saline-diluted contrast solution with low-pressure infusion through the Foley catheter. The cystograms were evaluated blindly by a single radiologist. All patients were examined by cystoscopy and/or CT every 3 months for the first 2 years postoperatively. Results: The cystogram showed contrast leaking compatible with bladder perforation in 17 (50%) cases. None of the perforations were recognized intraoperatively by the surgeon. All perforations were extraperitoneal and managed conservatively. There was no significant correlation between the incidence of bladder perforation and the patient age (p = 0.508), the tumor stage (p = 0.998), the tumor grade (p = 0.833), the number of lesions (p = 0.394), and the tumor size (p = 0.651). The only factor that had impact on the development of bladder perforation was tumor localization at the bottom of the bladder (p = 0.035; OR, 6750; 95% CI, 1.14, 39.8). Conclusion: Asymptomatic perforations of the bladder wall occur very frequently after a TURB procedure performed by residents in training and, most of the time, are not noticed by the surgeon. Localization of the tumor at bladder dome was the only factor that negatively influenced perforation rates.

Charles Darwin goes to school: the role of cartoons and narrative in setting science in an historical context

Science education is under revision. Recent changes in society require changes in education to respond to new demands. Scientific literacy can be considered a new goal of science education and the epistemological gap between natural sciences and literacy disciplines must be overcome. The history of science is a possible bridge to link these `two cultures` and to foster an interdisciplinary approach in the classroom. This paper acknowledges Darwin`s legacy and proposes the use of cartoons and narrative expositions to put this interesting chapter of science into its historical context. A five-lesson didactic sequence was developed to tell part of the story of Darwin`s expedition through South America for students from 10 to 12 years of age. Beyond geological and biological perspectives, the inclusion of historical, social and geographical facts demonstrated the beauty and complexity of the findings that Darwin employed to propose the theory of evolution.

City tuberculosis control coordinators` perspectives of patient adherence to DOT in Sao Paulo State, Brazil, 2005

SETTING: Thirty-six priority cities in Sao Paulo State, Brazil, with a high incidence of tuberculosis (TB) cases, deaths and treatment default. OBJECTIVE: To identify the perspectives of city TB control coordinators regarding the most important components of adherence strategies adopted by health care teams to ensure patient adherence in 36 priority cities in the State of Sao Paulo, Brazil. DESIGN: Qualitative research with semi-structured interviews conducted with the coordinators of the National TB Control Programme involved in the management of TB treatment services in the public sector. RESULTS: The main issues thought to influence adherence to directly observed treatment (DOT) by coordinators include incentives and benefits delivered to patients, patient-health care worker bonding and comprehensive care, the encouragement given by others to follow treatment (family, neighbours and health professionals), and help provided by health professionals for patients to recover their self-esteem. CONCLUSION: The main aspects mentioned by city TB control coordinators regarding patient adherence to treatment and to DOT in Sao Paulo are improvements in communications, relationships based on trust, a humane approach and including the patients in the decision-making process concerning their health.

Adult language input in the early childhood educational setting

Age-related changes in the adult language addressed to children aged 2;0-4;0 years in polyadic conditions were investigated in Australian childcare centres. The language that 21 staff members addressed to these children was coded for multiple variables in the broad social categories of prosody, context, speech act and gesture. The linguistic components were coded within the categories of phonology, lexicon, morphology, syntax and referential deixis. Minimal age-related differences were found. Explanations for the similarity of the adult language input across the age groups within the early childhood educational environment, will be discussed

Parameter setting and statistical learning

Three main models of parameter setting have been proposed: the Variational model proposed by Yang (2002; 2004), the Structured Acquisition model endorsed by Baker (2001; 2005), and the Very Early Parameter Setting (VEPS) model advanced by Wexler (1998). The VEPS model contends that parameters are set early. The Variational model supposes that children employ statistical learning mechanisms to decide among competing parameter values, so this model anticipates delays in parameter setting when critical input is sparse, and gradual setting of parameters. On the Structured Acquisition model, delays occur because parameters form a hierarchy, with higher-level parameters set before lower-level parameters. Assuming that children freely choose the initial value, children sometimes will miss-set parameters. However when that happens, the input is expected to trigger a precipitous rise in one parameter value and a corresponding decline in the other value. We will point to the kind of child language data that is needed in order to adjudicate among these competing models.

A multi-sectorial committee in directing HIV/AIDS-specific interventions in the occupational setting: An example from South Africa

We present a descriptive analysis of a mechanism to coordinate and implement human immunodeficiency virus (HIV) prevention and care in the occupational setting. The mechanism we describe is a multidisciplinary committee composed of stakeholders in the occupational health environment including unions, management, medical researchers, and medical personnel. The site chosen for the analysis was a South African sugar mill in rural KwaZulu-Natal. The factory is situated in an area of high HIV seroprevalence and has a workforce of 400 employees. The committee was initiated to coordinate a combined prevention-care initiative. The issues that were important in the formation of the committee included confidentiality, trust, and the traditional roles of the stakeholder relationships. When these points were addressed through the focus on a common goal, the committee was able to function in its role as a coordinating body. Central to this success was the inclusion of all stakeholders in the process, including those with traditionally opposing, interests and legitimacy conferred by the stakeholders. This committee was functionally effective and demonstrated the benefit of a freestanding committee dedicated to addressing HIV/acquired immune deficiency syndrome (AIDS) issues. We describe the implementation and feasibility of a multisectoral committee in directing HIV/AIDS initiatives in the occupational setting in rural South Africa.

Predicting energy requirements in the clinical setting: Are current methods evidence based?

Estimating energy requirements is necessary in clinical practice when indirect calorimetry is impractical. This paper systematically reviews current methods for estimating energy requirements. Conclusions include: there is discrepancy between the characteristics of populations upon which predictive equations are based and current populations; tools are not well understood, and patient care can be compromised by inappropriate application of the tools. Data comparing tools and methods are presented and issues for practitioners are discussed. (C) 2003 International Life Sciences Institute.

The determinants of default risk in Brazil

We formulated a general unrestricted model of the Brazilian Emerging Markets Bond Index Plus (EMBI+) spreads, a proxy for the country`s default risk. Employing algorithms that perform automated model selection, we found that macroeconomic fundamentals, such as current account deficit ratio to gross domestic product, public deficit ratio to gross domestic product and imports over foreign exchange reserves, can explain a great part of the variation in EMBI+ spreads. There is also robust evidence of systematic contagion from Argentina and Mexico and that the variance of the spread also affects its mean.

ICRAM (the International Campaign to Revitalise Academic Medicine): Agenda setting

Following die launch by the BMJ and others of the campaign to promote academic medicine, a working party of 20 medical academics from all over the world was convened to develop a plan of action.

Occasion setting in Pavlovian ambiguous target discriminations

Rats were trained in a Pavlovian serial ambiguous target discrimination, in which a target cue was reinforced if it was preceded by one stimulus (P -> T+) but was not reinforced if it was preceded by another stimulus (N -> T-). Test performance indicated that stimulus control by these features was weaker than that acquired by features trained within separate serial feature positive (P -> T+, T-) and serial feature negative (N -> W-, W+) discriminations. The form of conditioned responding and the patterns of transfer observed suggested that the serial ambiguous target discrimination was solved by occasion setting. The data are discussed in terms of the use of retrospective coding strategies when solving Pavlovian serial conditional discriminations, and the acquisition of special properties by both feature and target stimuli. (C) 2008 Published by Elsevier B.V.