Current management practices for acromegaly: an international survey

To determine whether peer-reviewed consensus statements have changed clinical practice, we surveyed acromegaly care in specialist centers across the globe, and determined the degree of adherence to published consensus guidelines on acromegaly management. Sixty-five acromegaly experts who participated in the 7th Acromegaly Consensus Workshop in March 2009 responded. Results indicated that the most common referring sources for acromegaly patients were other endocrinologists (in 26% of centers), neurosurgeons (25%) and primary care physicians (21%). In sixty-nine percent of patients, biochemical diagnoses were made by evaluating results of a combination of growth hormone (GH) nadir/basal GH and elevated insulin like growth factor-I (IGF-I) levels. In both Europe and the USA, neurosurgery was the treatment of choice for GH-secreting microadenomas and for macroadenomas with compromised visual function. The most widely used criteria for neurosurgical outcome assessment were combined measurements of IGF-I and GH levels after oral glucose tolerance test (OGTT) 3 months after surgery. Ninety-eight percent of respondents stated that primary treatment with somatostatin receptor ligands (SRLs) was indicated at least sometime during the management of acromegaly patients. In nearly all centers (96%), the use of pegvisomant monotherapy was restricted to patients who had failed to achieve biochemical control with SRL therapy. The observation that most centers followed consensus statement recommendations encourages the future utility of these workshops aimed to create uniform management standards for acromegaly.

Involvement of median raphe nucleus 5-HT1A receptors in the regulation of generalized anxiety-related defensive behaviours in rats

Changes in 5-HT1A receptor-mediated neurotransmission at the level of the median raphe nucleus (MRN) are reported to affect the expression of defensive responses that are associated with generalized anxiety disorder (e.g. inhibitory avoidance) but not with panic (e.g. escape). The objective of this study was to further explore the involvement of MRN 5-HT1A receptors in the regulation of generalized anxiety-related behaviours. Results of experiment 1 showed that intra-MRN injection of the 5-HT1A/7 receptor agonist 8-OH-DPAT (0.6 nmol) in male Wistar rats impaired the acquisition of inhibitory avoidance, without interfering with the performance of escape in the elevated T-maze test of anxiety. Pre-treatment with the 5-HT1A receptor antagonist WAY-100635 (0.18 nmol) fully blocked this anxiolytic-like effect. As revealed by experiment 2, intra-MRN injection of 8-OH-DPAT (0.6, 3 or 15 nmol) also caused anxiolytic effect in rats submitted to the light-dark transition test, another animal model that has been associated with generalized anxiety. In the same test, intra-MRN injection of WAY-100635 (0.18, 0.37 or 0.74 nmol) caused the opposite effect. Overall, the current findings support the view that MRN 5-HT neurons, through the regulation of 5-HT1A somatodendritic autoreceptors, are implicated in the regulation of generalized anxiety-associated behaviours. (C) 2008 Elsevier Ireland Ltd. All rights reserved.

Epidemiology of meningococcal disease in Latin America: current situation and opportunities for prevention

Objective: Meningococcal disease continues to be a serious public health concern, being associated with high morbidity and mortality rates in many countries from Latin America. In addition to discussing recent changes in the epidemiology of meningococcal disease in the region, we also analyse the development and potential impact of new vaccines on the prevention of meningococcal disease. Methods: MEDLINE, SciELO, LILACS and websites of the national Ministries of Health databases were searched using the terms meningococcal disease, meningococcal epidemiology, Neisseria meningitidis, meningococcal vaccines and the name of Latin America countries, from 1998 to 2008, with emphasis on review articles, clinical trials and epidemiological studies. Results: Epidemiology of meningococcal disease in Latin America is characterized by marked differences from country to country. The overall incidence of meningococcal disease per year varied from less than 0.1 cases per 100,000 inhabitants in countries like Mexico to two cases per 100,000 inhabitants in Brazil. The highest age-specific incidence of meningococcal disease occurred in infants less than 1 year of age. Serogroups B and C were responsible for the majority of cases reported, but the emergence of serogroups W135 and Y was reported in some countries. Serogroup A disease is now rare in Latin America. Discussion: Although a few countries have established meningitis surveillance programs, the information is not uniform, and the quality of the reported data is poor in the majority of the region. The availability of new effective meningococcal conjugate vaccines and promising protein-based vaccine candidates against meningococcus B highlights the importance of a better understanding of the true burden of meningococcal disease in Latin America and also the need for cost-effectiveness studies before incorporating the new meningococcal vaccines to national immunization programs.

Current developments on Schistosoma proteomics

Several papers on Schistosoma mansoni and Schistosoma japonicum proteomes have been published worldwide in the past few years, representing an emerging field of study. Knowledge of the schistosome proteome may greatly enhance our understanding of schistosome physiological processes at the molecular level, and may provide new models for development of vaccines or drugs. Despite the importance of this approach. schistosome proteomic research in Brazil is still incipient. Here we review the development of schistosome proteomic research around the world and provide an appreciation on the future opportunities in Brazil. (c) 2008 Elsevier B.V. All rights reserved

Alzheimer`s disease diagnosis disclosure in Brazil: a survey of specialized physicians` current practice and attitudes

Background: There is little, though growing, interest in the research area of attitudes held among physicians towards disclosing the diagnosis of dementia and Alzheimer`s disease (AD), or the current practice on AD disclosure. This study aimed to investigate the practice and attitudes of specialized physicians towards AD diagnosis disclosure in Brazil. Methods: A questionnaire was devised to survey the current practice and attitudes regarding diagnosis disclosure of AD in Brazil and sent to specialized physicians (170 geriatricians, 300 neurologists and 500 psychiatrists) by electronic mail. Results: From 970 potential respondents, 181 physicians who usually attend AD patients returned the questionnaire. There were no significant differences between the three specialties regarding the frequency with which they informed patients of their AD diagnosis (p = 0.17). The results revealed that only 44.8% of the physicians would regularly inform the patient of the diagnosis, although 85.6% of these use clear terminology. Despite their usual practice, 76.8% would want to know their diagnosis if they themselves were affected by AD. Conclusions: Disclosure of AD diagnosis is not common among specialized physicians in Brazil and different factors are involved. In the clinical context, discussion on advantages of diagnosis disclosure can be useful for improving the care of AD patients and their families.

Articular Cartilage in the Knee: Current MR Imaging Techniques and Applications in Clinical Practice and Research

Magnetic resonance (MR) imaging is the most important imaging modality for the evaluation of traumatic or degenerative cartilaginous lesions in the knee. It is a powerful noninvasive tool for detecting such lesions and monitoring the effects of pharmacologic and surgical therapy. The specific MR imaging techniques used for these purposes can be divided into two broad categories according to their usefulness for morphologic or compositional evaluation. To assess the structure of knee cartilage, standard spin-echo (SE) and gradient-recalled echo (GRE) sequences, fast SE sequences, and three-dimensional SE and GRE sequences are available. These techniques allow the detection of morphologic defects in the articular cartilage of the knee and are commonly used in research for semiquantitative and quantitative assessments of cartilage. To evaluate the collagen network and proteoglycan content in the knee cartilage matrix, compositional assessment techniques such as T2 mapping, delayed gadolinium-enhanced MR imaging of cartilage (or dGEMRIC), T1 rho imaging, sodium imaging, and diffusion-weighted imaging are available. These techniques may be used in various combinations and at various magnetic field strengths in clinical and research settings to improve the characterization of changes in cartilage. (C)RSNA, 2011 , radiographics.rsna.org

Argon ion laser and halogen lamp activation of a dark and light resin composite: microhardness after long-term storage

The objective of this study was to evaluate in vitro light activation of the nano-filled resin composite Vita shade A1 and A3 with a halogen lamp (QTH) and argon ion laser by Knoop microhardness profile. Materials and methods: Specimens of nanofilled composite resin (Z350-3 M-ESPE) Vita shade A1 and A3 were prepared with a single increment inserted in 2.0-mm-thick and 3-mm diameter disc-shaped Teflon mold. The light activation was performed with QTH for 20 s (with an intensity of approximately 1,000 mW/cm(2) and 700 mW/cm(2)) and argon ion laser for 10 s (with a power of 150 mW and 200 mW). Knoop microhardness test was performed after 24 h and 6 months. The specimens were divided into the 16 experimental groups (n = 10), according to the factors under study: photoactivation form, resin shade, and storage time. Knoop microhardness data was analyzed by a factorial ANOVA and TukeyA ` s tests at the 0.05 level of significance. Results: Argon ion laser was not able to photo-activate the darker shade of the nanofilled resin composite evaluated but when used with 200 mW it can be as effective as QTH to photo-activate the lighter shade with only 50% of the time exposure. After 6 months storage, an increase in the means of Knoop microhardness values were observed. Conclusions: Light-activation significantly influenced the Knoop microhardness values for the darker nanofilled resin composite.

Polymerization stress, shrinkage and elastic modulus of current low-shrinkage restorative composites

Objective. To compare currently available low-shrinkage composites with others regarding polymerization stress, volumetric shrinkage (total and post-gel), shrinkage rate and elastic modulus. Methods. Seven BisGMA-based composites (Durafill/DU, Filtek Z250/FZ, Heliomolar/HM, Aelite LS Posterior/AP, Point 4/P4, Filtek Supreme/SU, ELS/EL), a silorane-based (Filtek LS, LS), a urethane-based (Venus Diamond, VD) and one based on a dimethacrylate-derivative of dimer acid (N`Durance, ND) were tested. Polymerization stress was determined in 1-mm high specimens inserted between two PMMA rods attached to a universal testing machine. Total volumetric shrinkage was measured using a mercury dilatometer. Maximum shrinkage rate was used as a parameter of the reaction speed. Post-gel shrinkage was measured using strain-gages. Elastic modulus was obtained by three-point bending. Data were submitted to one-way ANOVA/Tukey test (p = 0.05), except for elastic modulus (Kruskal-Wallis). Results. Composites ranked differently for total and post-gel shrinkage. Among the materials considered as ""low-shrinkage"" by the respective manufacturers, LS, EL and VD presented low post-gel shrinkage, while AP and ND presented relatively high values. Polymerization stress showed a strong correlation with post-gel shrinkage except for LS, which presented high stress. Elastic modulus and shrinkage rate showed weak relationships with polymerization stress. Significance. Not all low-shrinkage composites demonstrated reduced polymerization shrinkage. Also, in order to effectively reduce polymerization stress, a low post-gel shrinkage must be associated to a relatively low elastic modulus. (C) 2010 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

Ethanol Wet-bonding Challenges Current Anti-degradation Strategy

The long-term effectiveness of chlorhexidine as a matrix metalloproteinase (MMP) inhibitor may be compromised when water is incompletely removed during dentin bonding. This study challenged this anti-bond degradation strategy by testing the null hypothesis that wet-bonding with water or ethanol has no effect on the effectiveness of chlorhexidine in preventing hybrid layer degradation over an 18-month period. Acid-etched dentin was bonded under pulpal pressure simulation with Scotchbond MP and Single Bond 2, with water wet-bonding or with a hydrophobic adhesive with ethanol wet-bonding, with or without pre-treatment with chlorhexidine diacetate (CHD). Resin-dentin beams were prepared for bond strength and TEM evaluation after 24 hrs and after aging in artificial saliva for 9 and 18 mos. Bonds made to ethanol-saturated dentin did not change over time with preservation of hybrid layer integrity. Bonds made to CHD pre-treated acid-etched dentin with commercial adhesives with water wet-bonding were preserved after 9 mos but not after 18 mos, with severe hybrid layer degradation. The results led to rejection of the null hypothesis and highlight the concept of biomimetic water replacement from the collagen intrafibrillar compartments as the ultimate goal in extending the longevity of resin-dentin bonds.

Emerging technologies for the prevention of dental caries. Are current methods of prevention sufficient for the high risk patient?

Fluorides and chlorhexidine are technologies that are 65 and 40 years old, respectively. This overview argues that current methods of caries prevention are not effective for the high caries risk patient. In this review examples, arguments and recommendations are provided to address the high caries risk patient that include: failure of comprehensive chemical modalities treatments to address the high caries risk patient; ecological alteration - would this be an effective approach?; and biomaterials and oral microbiome research to address the high caries risk patient.

Associations of dietary dark-green and deep-yellow vegetables and fruits with cervical intraepithelial neoplasia: modification by smoking

Smoking has been positively and fruit and vegetable intake has been negatively associated with cervical cancer, the second most common cancer among women worldwide. However, a lower consumption of fruits and reduced serum carotenoids have been observed among smokers. It is not known whether the smoking effect on the risk of cervical neoplasia is modified by a low intake of fruits and vegetables. The present study examined the combined effects of tobacco smoking and diet using a validated FFQ and serum carotenoid and tocopherol levels on cervical intraepithelial neoplasia grade 3 (CIN3) risk in a hospital-based case-control study conducted in Sao Paulo, Brazil, between 2003 and 2005. The sample comprised 231 incident, histologically confirmed cases of CIN3 and 453 controls. A low intake (<= 39 g) of dark-green and deep-yellow vegetables and fruits without tobacco smoking had a lesser effect on CIN3 (OR 1.14; 95% CI 0.49, 2.65) than among smokers with higher intake (>= 40 g; OR 1.83; 95% CI 0.73, 4.62) after adjusting for confounders. The OR for the joint exposure of tobacco smoking and low intake of vegetables and fruits was greater (3.86; 95% CI 1.74, 8.57; P for trend < 0.001) compared with non-smokers with higher intake after adjusting for confounding variables and human papillomavirus status. Similar results were observed for total fruit, serum total carotene (including beta-, alpha-and gamma-carotene) and tocopherols. These findings suggest that the effect of nutritional factors on CIN3 is modified by smoking.

Random primordial magnetic fields and the gas content of dark matter haloes

We recently predicted the existence of random primordial magnetic fields (RPMFs) in the form of randomly oriented cells with dipole-like structure with a cell size L(0) and an average magnetic field B(0). Here, we investigate models for primordial magnetic field with a similar web-like structure, and other geometries, differing perhaps in L(0) and B(0). The effect of RPMF on the formation of the first galaxies is investigated. The filtering mass, M(F), is the halo mass below which baryon accretion is severely depressed. We show that these RPMF could influence the formation of galaxies by altering the filtering mass and the baryon gas fraction of a halo, f(g). The effect is particularly strong in small galaxies. We find, for example, for a comoving B(0) = 0.1 mu G, and a reionization epoch that starts at z(s) = 11 and ends at z(e) = 8, for L(0) = 100 pc at z = 12, the f(g) becomes severely depressed for M < 10(7) M(circle dot), whereas for B(0) = 0 the f(g) becomes severely depressed only for much smaller masses, M < 10(5) M(circle dot). We suggest that the observation of M(F) and f(g) at high redshifts can give information on the intensity and structure of primordial magnetic fields.

The effect of a single supernova explosion on the cuspy density profile of a small-mass dark matter halo

Some observations of galaxies, and in particular dwarf galaxies, indicate a presence of cored density profiles in apparent contradiction with cusp profiles predicted by dark matter N-body simulations. We constructed an analytical model, using particle distribution functions (DFs), to show how a supernova (SN) explosion can transform a cusp density profile in a small-mass dark matter halo into a cored one. Considering the fact that an SN efficiently removes matter from the centre of the first haloes, we study the effect of mass removal through an SN perturbation in the DFs. We find that the transformation from a cusp into a cored profile occurs even for changes as small as 0.5 per cent of the total energy of the halo, which can be produced by the expulsion of matter caused by a single SN explosion.

An accelerating cosmology without dark energy

The negative pressure accompanying gravitationally-induced particle creation can lead to a cold dark matter (CDM) dominated, accelerating Universe (Lima et al. 1996 [1]) without requiring the presence of dark energy or a cosmological constant. In a recent study, Lima et al. 2008 [2] (LSS) demonstrated that particle creation driven cosmological models are capable of accounting for the SNIa observations [3] of the recent transition from a decelerating to an accelerating Universe, without the need for Dark Energy. Here we consider a class of such models where the particle creation rate is assumed to be of the form Gamma = beta H + gamma H(0), where H is the Hubble parameter and H(0) is its present value. The evolution of such models is tested at low redshift by the latest SNe Ia data provided by the Union compilation [4] and at high redshift using the value of z(eq), the redshift of the epoch of matter - radiation equality, inferred from the WMAP constraints on the early Integrated Sachs-Wolfe (ISW) effect [5]. Since the contributions of baryons and radiation were ignored in the work of LSS, we include them in our study of this class of models. The parameters of these more realistic models with continuous creation of CDM are constrained at widely-separated epochs (z(eq) approximate to 3000 and z approximate to 0) in the evolution of the Universe. The comparison of the parameter values, {beta, gamma}, determined at these different epochs reveals a tension between the values favored by the high redshift CMB constraint on z(eq) from the ISW and those which follow from the low redshift SNIa data, posing a potential challenge to this class of models. While for beta = 0 this conflict is only at less than or similar to 2 sigma, it worsens as beta increases from zero.

Attenuation and damping of electromagnetic fields: influence of inertia and displacement current

New results for attenuation and damping of electromagnetic fields in rigid conducting media are derived under the conjugate influence of inertia due to charge carriers and displacement current. Inertial effects are described by a relaxation time for the current density in the realm of an extended Ohm`s law. The classical notions of poor and good conductors are rediscussed on the basis of an effective electric conductivity, depending on both wave frequency and relaxation time. It is found that the attenuation for good conductors at high frequencies depends solely on the relaxation time. This means that the penetration depth saturates to a minimum value at sufficiently high frequencies. It is also shown that the actions of inertia and displacement current on damping of magnetic fields are opposite to each other. That could explain why the classical decay time of magnetic fields scales approximately as the diffusion time. At very small length scales, the decay time could be given either by the relaxation time or by a fraction of the diffusion time, depending on whether inertia or displacement current, respectively, would prevail on magnetic diffusion.