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We present a comprehensive review of keV-scale sterile neutrino Dark Matter, collecting views and insights from all disciplines involved - cosmology, astrophysics, nuclear, and particle physics - in each case viewed from both theoretical and experimental/observational perspectives. After reviewing the role of active neutrinos in particle physics, astrophysics, and cosmology, we focus on sterile neutrinos in the context of the Dark Matter puzzle. Here, we first review the physics motivation for sterile neutrino Dark Matter, based on challenges and tensions in purely cold Dark Matter scenarios. We then round out the discussion by critically summarizing all known constraints on sterile neutrino Dark Matter arising from astrophysical observations, laboratory experiments, and theoretical considerations. In this context, we provide a balanced discourse on the possibly positive signal from X-ray observations. Another focus of the paper concerns the construction of particle physics models, aiming to explain how sterile neutrinos of keV-scale masses could arise in concrete settings beyond the Standard Model of elementary particle physics. The paper ends with an extensive review of current and future astrophysical and laboratory searches, highlighting new ideas and their experimental challenges, as well as future perspectives for the discovery of sterile neutrinos.

Primary infection with one of four dengue virus serotypes (DENV1-4) may generate antibodies that protect or enhance subsequent secondary heterotypic infections. However, the characteristics of heterotypic cross-reactive antibodies associated with protection from symptomatic infection and severe disease are not well-defined. We selected plasma samples collected before a secondary DENV heterotypic infection that was classified either as dengue fever (DF, n = 31) or dengue hemorrhagic fever/dengue shock syndrome (DHF/DSS, n = 33) from our longstanding pediatric cohort in Nicaragua. We screened various antibody properties to determine the features correlated with protection from DHF/DSS. Protection was associated with high levels of binding of various antibody isotypes, IgG subclasses and effector functions, including antibody-dependent complement deposition, ADCD. Although the samples were derived from DENV-exposed, Zika virus (ZIKV)-naïve individuals, the protective ADCD association was stronger when assays were conducted with recombinant ZIKV antigens. Further, we showed that a complement-mediated virion lysis (virolysis) assay conducted with ZIKV virions was strongly associated with protection, a finding reproduced in an independent sample set collected prior to secondary heterotypic inapparent versus symptomatic DENV infection. Virolysis was the main antibody feature correlated with protection from DHF/DSS and severe symptoms, such as thrombocytopenia, hemorrhagic manifestations, and plasma leakage. Hence, anti-DENV antibodies that cross-react with ZIKV, target virion-associated epitopes, and mediate complement-dependent virolysis are correlated with protection from secondary symptomatic DENV infection and DHF/DSS. These findings may support the rational design and evaluation of dengue vaccines and development of therapeutics., Competing Interests: Competing interests EH laboratory received research funds from Takeda Vaccines Inc. to test samples from vaccine recipients. EH served on one-time advisory boards for Merck and Takeda. The other authors declare no competing interests.

Background: Leukemias stand out for being the main type of childhood cancer in the world. Current treatments have strong side effects for patients, and there is still a high rate of development of resistance to multidrug therapy. Previously, our research group developed a structure-activity study with novel synthetic molecules analogous to LQB-278, described as an essential molecule with in vitro antileukemic action. Among these analogs, LQB-461 stood out, presenting more significant antileukemic action compared to its derivative LQB-278, with cytostatic and cytotoxicity effect by apoptosis, inducing caspase-3, and increased sub-G1 phase on cell cycle analysis., Methods and Results: Deepening the study of the mechanism of action of LQB-461 in Jurkat cells in vitro, a microarray assay was carried out, which confirmed the importance of the apoptosis pathway in the LQB-461 activity. Through real-time PCR, we validated an increased expression of CDKN1A and BAX genes, essential mediators of the apoptosis intrinsic pathway. Through the extrinsic apoptosis pathway, we found an increased expression of the Fas receptor by flow cytometry, showing the presence of a more sensitive population and another more resistant to death. Considering the importance of autophagy in cellular resistance, it was demonstrated by western blotting that LQB-461 decreased LC-3 protein expression, an autophagic marker., Conclusions: These results suggest that this synthetic molecule LQB-461 induces cell death by apoptosis in Jurkat cells through intrinsic and extrinsic pathways and inhibits autophagy, overcoming some mechanisms of cell resistance related to this process, which differentiates LQB-461 of other drugs used for the leukemia treatment., (© 2024. The Author(s), under exclusive licence to Springer Nature B.V.)

Introduction: This study aims to assess the proficiency level of digital skills, the factors influencing that level and the training needs of Therapeutic Radiographers/Radiation Therapists (TR/RTTs), due to the differences in technology availability and accessibility, variations in the regulation and education of TR/RTTs in European countries, and the lack of a digital skills framework., Methods: An online survey was distributed to TR/RTTs working in Europe to capture their self-assessment of proficiency levels of digital skills when performing their clinical role. Information was also gathered regarding training, work experience and level of information and communication technology (ICT) skills. Quantitative measures were analysed using descriptive statistics and correlation between variables, and qualitative responses using thematic analysis., Results: 101 respondents from 13 European countries completed the survey. Digital skills in treatment planning followed by management and research were the least developed skills, while the most developed were transversal digital skills followed by digital skills in treatment delivery. The Radiotherapy areas of practice where TR/RTT has experience (e.g. Planning Image, Treatment Planning, Treatment), as well as the level of generic ICT skills (communication, content creation and problem-solving), was related to the level of proficiency of TR/RTT digital skills. Greater scope of practice and level of generic ICT were associated with a higher level of TR/RTT digital skills. Thematic analysis allowed the identification of new sub-themes to be included in the training of TR/RTTs., Conclusion: Education and training of TR/RTTs should be improved and adapted to the current needs of digitalisation to avoid differences in digital proficiency levels., Implications for Practice: Aligning TR/RTTs' digital skill sets with emerging digitalisation will improve current practice and ensure the best care to all RT patients., Competing Interests: Conflict of interest statement This work was co-funded by the SAFE EUROPE project under the Erasmus+ Sector Skill Alliances programme [grant agreement 2018-2993/001-001]. The European Commission support for the production of this publication does not constitute an endorsement of the contents which reflects the views only of the authors, and the Commission cannot be held responsible for any use which may be made of the information contained therein. Jéssica Rodrigues is supported by a PhD fellowship from Fundação para a Ciência e a Tecnologia, Portugal (UI/BD/152282/2021)., (Copyright © 2023 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

In Latin America (LA), 40-50 million people live with rare diseases (RDs) that require constant monitoring, care, and attention. Caregivers help them with their basic life activities and medication administration, which they would otherwise be unable to perform. Family caregivers complement healthcare and social security systems; however, their unpaid work is often underappreciated and under-protected. Recognizing the need to address these unrecognized and undervalued women, the Americas Health Foundation (AHF) convened a panel of LA experts on caregiving for people with RDs to provide recommendations to support the undervalued family caregivers. A panel of LA experts in caregiving for RDs were given questions to address the challenges faced by family caregivers of people with RDs in LA. During a 3-day conference, the panelists' responses were discussed and edited until the panel agreed on recommendations to address the challenges. The identified challenges for caregivers included physical, emotional, and economical areas. Caregivers, primarily women, experienced physical pain, and social isolation, and were forced to pay substantial out-of-pocket expenses in their caregiving roles. Brazil and Colombia are at the forefront of policies to protect caregivers and their experiences in attempting to provide for this group are outlined as case studies for what is possible in LA. Finally, recognizing that caregivers must be included in formulating, executing, and evaluating care policies for people living with RDs and that the caregivers themselves require social assurances, the panel suggested policy objectives aimed at protecting caregivers of people living with RDs. The recommendations ranged from recognizing the role of the family caregiver as an essential supplement to the formal healthcare system to providing financial assistance, training, and workplace protection, among others. Finally, monitoring and evaluating the impact of policies is necessary to ensure that LA is moving forward in caring for family caregivers for people with RDs., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest, (Copyright © 2023 Dias, Daher, Barrera Ortiz, Carreño-Moreno, Hafez H, Jansen, Rico-Restrepo and Chaparro-Diaz.)

Poly(ethylene terephthalate) (PET) is one of the main synthetic plastics produced worldwide. The extensive use of this polymer causes several problems due to its low degradability. In this scenario, biocatalysts dawn as an alternative to enhance PET recycling. The enzymatic hydrolysis of PET results in a mixture of terephthalic acid (TPA), ethylene glycol (EG), mono-(2-hydroxyethyl) terephthalate (MHET) and bis-(2-hydroxyethyl) terephthalate (BHET) as main products. This work developed a new methodology to quantify the hydrolytic activity of biocatalysts, using BHET as a model substrate. The protocol can be used in screening enzymes for PET depolymerization reactions, amongst other applications. The very good fitting (R 2 = 0.993) between experimental data and the mathematical model confirmed the feasibility of the Michaelis-Menten equation to analyze the effect of BHET concentration (8-200 mmol L -1 ) on initial hydrolysis rate catalyzed by Humicola insolens cutinase (HiC). In addition to evaluating the effects of enzyme and substrate concentration on the enzymatic hydrolysis of BHET, a novel and straightforward method for MHET synthesis was developed using an enzyme load of 0.025 g protein g BHET -1 and BHET concentration of 60 mmol L -1 at 40 °C. MHET was synthesized with high selectivity (97 %) and yield (82 %). The synthesized MHET properties were studied using differential scanning calorimetry (DSC), thermogravimetry (TGA), and proton nuclear magnetic resonance ( 1 H NMR), observing the high purity of the final product (86.7 %). As MHET is not available commercially, this synthesis using substrate and enzyme from open suppliers adds new perspectives to monitoring PET hydrolysis reactions., Competing Interests: Declaration of Competing Interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Erika de Queiros Eugenio reports financial support was provided by Coordination of Higher Education Personnel Improvement. Maria Alice Zarur Coelho reports financial support was provided by Carlos Chagas Filho Foundation for Research Support of Rio de Janeiro State. Maria Alice Zarur Coelho reports financial support was provided by Petrobras. Maria Alice Zarur Coelho reports financial support was provided by National Council for Scientific and Technological Development., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Introduction: It is estimated that around 50% of cancer patients require Radiotherapy (RT) at some point during their treatment, hence Therapeutic Radiographers/Radiation Therapists (TR/RTTs) have a key role to play in patient management. It is essential for TR/RTTs to keep abreast with new technologies and continuously develop the digital skills necessary for safe RT practice. The RT profession and education is not regulated at European Union level, which leads to heterogeneity in the skills developed and practised among countries. This study aimed to explore the white and grey literature to collate data on the relevant digital skills required for TR/RTTs practice., Methods: An exhaustive systematic search was conducted to identify literature discussing digital skills of TR/RTTs; relevant grey literature was also identified. A thematic analysis was performed to identify and organise these skills into themes and sub-themes., Results: 195 digital skills were identified, organised in 35 sub-themes and grouped into six main themes: (i) Transversal Digital Skills, (ii) RT Planning Image, (iii) RT Treatment Planning, (iv) RT Treatment Administration, (v) Quality, Safety and Risk Management, and (vi) Management, Education and Research., Conclusion: This list can be used as a reference to close current gaps in knowledge or skills of TR/RTTs while anticipating future needs regarding the rapid development of new technologies (such as Artificial Intelligence or Big Data)., Implications for Practice: It is imperative to align education with current and future RT practice to ensure that all RT patients receive the best care. Filling the gaps in TR/RTTs skill sets will improve current practice and provide TR/RTTs with the support needed to develop more advanced skills., Competing Interests: Conflict of interest statement This work was co-funded by the SAFE EUROPE project under the Erasmus+ Sector Skill Alliances programme [grant agreement 2018-2993/001-001]. The European Commission support for the production of this publication does not constitute an endorsement of the contents which reflects the views only of the authors, and the Commission cannot be held responsible for any use which may be made of the information contained therein., (Copyright © 2022 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Preexisting cross-reactive antibodies have been implicated in both protection and pathogenesis during subsequent infections with different dengue virus (DENV) serotypes (DENV1-4). Nonetheless, humoral immune correlates and mechanisms of protection have remained elusive. Using a systems serology approach to evaluate humoral responses, we profiled plasma collected before inapparent or symptomatic secondary DENV3 infection from our pediatric cohort in Nicaragua. Children protected from symptomatic infections had more anti-envelope (E) and anti-nonstructural protein 1 (NS1) total immunoglobulin G (IgG), IgG4, and greater Fc effector functions than those with symptoms. Fc effector functions were also associated with protection from hemorrhagic manifestations in the pre-symptomatic group. Furthermore, in vitro virological assays using these plasma samples revealed that protection mediated by antibody-dependent complement deposition was associated with both lysis of virions and DENV-infected cells. These data suggest that E- and NS1-specific Fc functions may serve as correlates of protection, which can be potentially applied toward the design and evaluation of dengue vaccines.

Purpose: Development of an independent MU calculator (StereoCalc) with and without heterogeneity corrections for stereotactic treatments, in a Varian TrueBeam STx LINAC using stereotactic cones, with flattening filter-free photon energies., Methods: Multiple depth curves and output factors were measured, following the dosimetry formalism for small fields proposed by the TRS-483. The developed StereoCalc imports and processes the beam data files and calculates the patient plans with and without heterogeneity correction. Validation of the developed software was carried out using phantoms. The accuracy of the StereoCalc software was verified in stereotactic patient plans., Results: A maximum difference of 2.47% and 2.07% was obtained in the phantom validation tests with and without heterogeneity correction, respectively. The mean percentual difference of StereoCalc from cone dose calculation (CDC) in the clinical testing was 2.86% ±1.27% and 0.78% ±0.48% with and without heterogeneity correction, respectively. The largest differences found were 7.34% and 1.98%, respectively., Conclusions: The results obtained in this work show that the MU calculated with StereoCalc software is in good agreement with the values calculated by the treatment planning systems, both in static fields and arcs. We have also improved the software to consider heterogeneity corrections calculations. As expected, and as a major achievement of this work, some differences were observed when heterogeneities were considered. StereoCalc proved to be a powerful tool that can be integrated into the specific quality assurance program in a medical physics department for independent verification in stereotactic treatment with cones., (© 2022 The Authors. Journal of Applied Clinical Medical Physics published by Wiley Periodicals, LLC on behalf of The American Association of Physicists in Medicine.)

Background/aim: A new set of LQB-nitrones and analogues was synthesized to evaluate anticancer activity based on the substitution of the terpenyl moiety of the antileukemic compound LQB-278 by the conformationally restricted cinnamyl ether., Materials and Methods: A structure-activity relationship study was performed in vitro on Jurkat cells to screen the antileukemic activity of LQB-nitrones and analogues and elucidate the mechanisms of action of the most active derivatives., Results: The cynamyl ramification and its ortho position aldehyde substitution improved the antileukemic activity. Three compounds showed an in vitro antiproliferative action, but only 5b induced apoptosis. Analysis of the molecular mechanisms showed increased expression of the cell cycle inhibitor p21CIP1/WAF1/Sdi1, caspase 3, Fas receptor, and Bax/Bcl-2 ratio., Conclusion: The cinnamyl derivative 5b (LQB-461) presented higher antileukemic effects than the prototype terpenyl nitrone, inducing Jurkat cell death by activating both extrinsic and intrinsic pathways of apoptosis. Therefore, this compound is a new promising candidate drug against leukemia., (Copyright © 2021 International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.)

5-Nitro-furan nitrones ( 1 ) and 5-nitro-thiophene nitrones ( 2 ) were synthesized in one step. Compounds 1a - c had the most potent leishmanicidal activity against intracellular amastigote forms of Leishmania amazonensis and L. infantum (from 0.019 to 2.76 μM), with excellent selectivity (from 39 to 5673). The comparison of the leishmanicidal activity in promastigotes of wild type L. donovani with those overexpressing nitroreductases NRT1 or NRT2 shows that 1a , b are activated by both, which could slow the development of resistance. Their redox potential ( E redox ) obtained by cyclic voltammetry (-0.67 and -0.62 V) shows that the reduction of the nitro group is modulated by the nitrone group. Oral administration of 1b to mice infected by L. infantum reduced the parasite load on the spleen by 76.6 and 95.0% with doses of 50 and 100 mg/kg, respectively, administered twice a day, for 5 days. In the liver, the parasite load suppression was above 75% with either treatment., Competing Interests: The authors declare no competing financial interest., (© 2021 American Chemical Society.)

Chagas disease, which is caused by Trypanosoma cruzi , establishes lifelong infections in humans and other mammals that lead to severe cardiac and gastrointestinal complications despite the competent immune response of the hosts. Furthermore, it is a neglected disease that affects 8 million people worldwide. The scenario is even more frustrating since the main chemotherapy is based on benznidazole, a drug that presents severe side effects and low efficacy in the chronic phase of the disease. Thus, the search for new therapeutic alternatives is urgent. In the present study, we investigated the activity of a novel phenyl-tert-butyl-nitrone (PBN) derivate, LQB303, against T. cruzi . LQB303 presented trypanocidal effect against intracellular [IC 50 /48 h = 2.6 μM] and extracellular amastigotes [IC 50 /24 h = 3.3 μM] in vitro , leading to parasite lysis; however, it does not present any toxicity to host cells. Despite emerging evidence that mitochondrial metabolism is essential for amastigotes to grow inside mammalian cells, the mechanism of redox-active molecules that target T. cruzi mitochondrion is still poorly explored. Therefore, we investigated if LQB303 trypanocidal activity was related to the impairment of the mitochondrial function of amastigotes. The investigation showed there was a significant decrease compared to the baseline oxygen consumption rate (OCR) of LQB303-treated extracellular amastigotes of T. cruzi , as well as reduction of "proton leak" (the depletion of proton motive force by the inhibition of F1Fo ATP synthase) and "ETS" (maximal oxygen consumption after uncoupling) oxygen consumption rates. Interestingly, the residual respiration ("ROX") enhanced about three times in LQB303-treated amastigotes. The spare respiratory capacity ratio (SRC: cell ability to meet new energy demands) and the ATP-linked OCR were also impaired by LQB303 treatment, correlating the trypanocidal activity of LQB303 with the impairment of mitochondrial redox metabolism of amastigotes. Flow cytometric analysis demonstrated a significant reduction of the ΔΨm of treated amastigotes. LQB303 had no significant influence on the OCR of treated mammalian cells, evidencing its specificity against T. cruzi mitochondrial metabolism. Our results suggest a promising trypanocidal activity of LQB303, associated with parasite bioenergetic inefficiency, with no influence on the host energy metabolism, a fact that may point to an attractive alternative therapy for Chagas disease., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Macedo, Saraiva, Paula, Nascimento, Costa, Costa, Dias, Paes and Nogueira.)

Objective  The present study verified, through a systematic review with meta-analysis, the effects of a rehabilitation, physical training program for the treatment of pain and muscle strength in knee osteoarthritis (OA). Methods  We analyzed studies published between 2008 and 2018 referenced at the Medline (National Library of Medicine) database, selecting 7 randomized controlled clinical trials about exercise programs to improve pain and muscle strength in patients with knee OA with Physiotherapy Evidence Database (PeDro) score higher than 8. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) systematization was used to prepare this review, and a meta-analysis was carried out to obtain mathematical evidence the outcomes of physical exercise on pain. Results  The studies included in the analysis contained a total of 934 participants aged 40 to 73 years-old, with 34.90% males. Most of the exercise sets offered in OA treatment had a significantly positive outcome result in both criteria, but mainly for pain relief (statistically significant difference, p  < 0.003). Conclusion  We infer that there was an improvement of pain in all articles that performed muscle strengthening, but there is still an obstacle to the protocols used., Competing Interests: Conflicts of Interest The authors declare that there is no conflict of interest., (The Author(s). This is an open access article published by Thieme under the terms of the Creative Commons Attribution-NonDerivative-NonCommercial-License, permitting copying and reproduction so long as the original work is given appropriate credit. Contents may not be used for commercial purposes, or adapted, remixed, transformed or built upon. ( https://creativecommons.org/licenses/by-nc-nd/4.0/ ).)

Radiobiology is moving towards a better understanding of the intercellular signaling that occurs upon radiation and how its effects relate to the dose applied. The mitochondrial role in orchestrating this biological response needs to be further explored. Cybrids (cytoplasmic hybrids) are useful cell models for studying the involvement of mitochondria in cellular processes. In the present study we used cybrid cell lines to investigate the role of mitochondria in the response to radiation exposure. Cybrid cell lines, derived from the osteosarcoma human cell line 143B, harboring, either wild-type mitochondrial DNA (Cy143Bwt), cells with mitochondria with mutated DNA that causes mitochondrial dysfunction (Cy143Bmut), as well as cells without mitochondrial DNA (mtDNA) (143B-Rho0), were irradiated with 0.2 Gy and 2.0 Gy. Evaluation of the non-targeted (or bystander) effects in non-irradiated cells were assessed by using conditioned media from the irradiated cells. DNA double stranded breaks were assessed with the γH2AX assay. Both directly irradiated cells and cells treated with the conditioned media, showed increased DNA damage. The effect of the irradiated cells media was different according to the cell line it derived from: from Cy143Bwt cells irradiated with 0.2 Gy (low dose) and from Cy143Bmut irradiated with 2.0 Gy (high dose) induced highest DNA damage. Notably, media obtained from cells without mtDNA, the143B-Rho0 cell line, produced no effect in DNA damage. These results point to a possible role of mitochondria in the radiation-induced non-targeted effects. Furthermore, it indicates that cybrid models are valuable tools for radiobiological studies.

In-phantom and in-vivo three dimensional conformal radiation therapy (3DCRT) and volumetric modulated arc therapy (VMAT) skin doses, measured with and without bolus in a female anthropomorphic phantom RANDO and in patients, were compared against treatment planning system calculated values. A thorough characterization of the metal oxide semiconductor field effect transistor measurement system was performed prior to the measurements in phantoms and patients. Patients with clinical indication for postoperative external radiotherapy were selected. Skin dose showed higher values with 3DCRT technique compared with VMAT. The increase in skin dose due to the use of bolus was quantified. It was observed that, in the case of VMAT, the bolus effect on the skin dose was considerable when compared with 3DCRT. From the point of view of treatment time, bolus cost, and positioning reproducibility, the use of bolus in these situations can be optimized., (© 2019 The Authors. Journal of Applied Clinical Medical Physics published by Wiley Periodicals, Inc. on behalf of American Association of Physicists in Medicine.)

Purpose: The purpose of this study was to evaluate the efficacy of needle holders in reducing staff hand exposure during biopsies guided by computed tomography fluoroscopy (CTF), through the analysis of data acquired during a detailed monitoring study, undertaken in parallel with an ongoing optimization process to reduce hand irradiation., Methods: Hand monitoring was performed with 11 extremity detectors, two per finger (base and tip) and one on the back of the wrist, for the left (dominant) hand, during two series of biopsies with comparable characteristics. The first series (47 biopsies) were performed with only quick-check method (QC) and occasional side-handle (SH) manipulation of the needle. The second series (63 biopsies) were performed after introducing needle holders (NH) in the course of an optimization process., Results: Choice of technique (QC, QC + NH, QC + SH) by the interventional radiologist (IR) was related to biopsy difficulty. Measured hand exposure was low (< 1 mSv) for all QC-only procedures, and for most of the QC + NH procedures. Occasional side-handle manipulation still occurred during challenging biopsies, so that 8% of biopsies in the second series accounted for ~70% of total fingertip dose (~90 mSv). The methodology used allowed a detailed insight into the dose reduction achievable with needle holders during real procedures, without the limitations of phantom measurements., Conclusions: Needle holders proved effective in reducing mean hand exposure during clinical procedures where real-time manipulation was necessary. Occasional side-handle manipulation was found to contribute disproportionately to hand exposure. This highlights the importance of individual hand monitoring during CTF guided procedures., (© 2017 The Authors. Journal of Applied Clinical Medical Physics published by Wiley Periodicals, Inc. on behalf of American Association of Physicists in Medicine.)

Background/objectives: Flax and Salba-chia seeds have risen in popularity owing to their favorable nutrient composition, including a high fiber content. Despite having comparable nutritional profiles, preliminary observations suggest differences in gelling properties, an attribute that may alter the kinetics of food digestion. Thus, we compared the effect of two seeds on postprandial glycemia and satiety scores., Subjects/methods: Fifteen healthy participants (M/F: 5/10; age: 23.9±3 years; BMI: 22.2±0.8 kg/m 2 ) were randomized to receive a 50 g glucose challenge, alone or supplemented with either 25 g ground Salba-chia or 31.5 g flax, on three separate occasions. Blood glucose samples and satiety ratings were collected at fasting and over 2-h postprandially. In addition, in vitro viscosity of the beverages was assessed utilizing standard rheological methodology., Results: Both Salba-chia and flax reduced blood glucose area under the curve over 120 min by 82.5±19.7 mmol/l (P<0.001) and 60.0±19.7 mmol/l (P=0.014), respectively, relative to a glucose control. Salba-chia reduced peak glucose (-0.64±0.24 mmol/l; P=0.030) and increased time to peak (11.3±3.8 min; P=0.015) compared with flax. Salba-chia significantly reduced the mean ratings of desire to eat (-7±2 mm; P=0.005), prospective consumption (-7±2 mm; P=0.010) and overall appetite score (-6±2 mm; P=0.012), when compared with flax. The viscosity of Salba-chia, flax and control was 49.9, 2.5, and 0.002 Pa·s, respectively., Conclusions: Despite the similarities in nutritional composition, Salba-chia appears to have the ability to convert glucose into a slow-release carbohydrate and affect satiety to a greater extent than flax, possibly due to the higher fiber viscosity. Incorporation of either flax or Salba-chia into the diet may be beneficial, although use of Salba-chia may confer additional benefit.

The therapeutic options for Chagas disease are limited and its treatment presents a number of drawbacks including toxicity, drug resistance, and insufficient effectiveness against the chronic stage of the disease. Therefore, new therapeutical options are mandatory. In the present work, we evaluated the effect of a phenyl- tert -butylnitrone (PBN) derivate, LQB 123, against Trypanosoma cruzi forms. LQB 123 presented a trypanocidal effect against bloodstream trypomastigotes (IC 50 = 259.4 ± 6.1  μ M) and intracellular amastigotes infecting peritoneal macrophages (IC 50 = 188.2 ± 47.5  μ M), with no harmful effects upon the mammalian cells (CC 50 values greater than 4 mM), resulting in a high selectivity index (CC 50 /IC 50 > 20). Additionally, metacyclic trypomastigotes submitted to LQB 123 presented an IC 50 of about 191.8 ± 10.5  μ M and epimastigotes forms incubated with different concentrations of LQB 123 presented an inhibition of parasite growth with an IC 50 of 255.1 ± 3.6  μ M. Finally, we investigated the mutagenic potential of the nitrone by the Salmonella /microsome assay and observed no induction of mutagenicity even in concentrations as high as 33000  μ M. Taken together, these results present a nonmutagenic compound, with trypanocidal activity against all relevant forms of T. cruzi , offering new insights into CD treatment suggesting additional in vivo tests., Competing Interests: The authors report no conflict of interests in this work.

Purpose: To study the impact of shielding elements in the proximity of Intra-Operative Radiation Therapy (IORT) irradiation fields, and to generate graphical and quantitative information to assist radiation oncologists in the design of optimal shielding during pelvic and abdominal IORT., Method: An IORT system was modeled with BEAMnrc and EGS++ Monte Carlo codes. The model was validated in reference conditions by gamma index analysis against an experimental data set of different beam energies, applicator diameters, and bevel angles. The reliability of the IORT model was further tested considering shielding layers inserted in the radiation beam. Further simulations were performed introducing a bone-like layer embedded in the water phantom. The dose distributions were calculated as 3D dose maps., Results: The analysis of the resulting 2D dose maps parallel to the clinical axis shows that the bevel angle of the applicator and its position relative to the shielding have a major influence on the dose distribution. When insufficient shielding is used, a hotspot nearby the shield appears near the surface. At greater depths, lateral scatter limits the dose reduction attainable with shielding, although the presence of bone-like structures in the phantom reduces the impact of this effect., Conclusions: Dose distributions in shielded IORT procedures are affected by distinct contributions when considering the regions near the shielding and deeper in tissue: insufficient shielding may lead to residual dose and hotspots, and the scattering effects may enlarge the beam in depth. These effects must be carefully considered when planning an IORT treatment with shielding., (Copyright © 2016 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.)

Computed tomography fluoroscopy (CTF) is a useful imaging technique to guide biopsies, particularly lung biopsies, but it also has the potential for very high hand exposures, despite use of quick-check method and needle holders whenever feasible. Therefore, reliable monitoring is crucial to ensure the safe use of CTF. This is a challenge, because ring dosimeters monitor exposure only at the base of one finger, while the fingertips may be exposed to the highly collimated CT beam. In this work we have explored the possibility of using Gafchromic XR-QA2 self-developing film as a complementary dosimeter to quantify hand exposure during CTF-guided biopsies. A glove used in a previous study and designed to contain 11 TLDs was adapted to include Gafchromic strips 7 mm wide, covering the fingers. A total of 22 biopsies were successfully performed wearing this GafTLD glove under sterile gloves, and the IR reported no difficulty or reduction of dexterity while wearing it. Comparison of dose distributions obtained from digitization of the Gafchromic film strips and absolute Hp(0.07) readings from TLDs showed good agreement, despite some positional uncertainty due to relative movement. Per procedure, doses at the base of the ring finger can be as low as 3%-8% of hand dose maximum. Accumulated dose at the base of the ring finger was four times lower than the dose maximum.

New O-isoprenylated-N-methylarylnitrones derived from isomeric o, m and p-hydroxybenzaldehydes have been prepared and the antineoplastic effects on human cancer cell lines were evaluated. The O-geranylated nitrone LQB-278 (1b) and its isomers 2b and 3b inhibited the NO production, but the anti-leukemic activity was drastically dependent on nitrone isomer, with the 1b being the most effective one (IC₅₀ of 6.7 μM) on Jurkat leukemia cell, by MTT assay. In addition, 1b up-regulated p21CIP1/WAF1/Sdi1 protein expression (flow cytometry), a cell cycle inhibitor, reduced cell growth, and induced DNA fragmentation (increased sub-G1 phase cells) and phosphatidylserine externalization in plasmatic membrane (increased annexin V positive cells). Finally, the 1b up-regulation of p21 expression and apoptosis induction seem to be the mechanisms by which it promotes its anti-leukemic effects, making this new molecular architecture a promising prototype for leukemia intervention., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

Background/aims: To determine whether variation in the TAS1R2 gene affects sucrose taste perception and sugar intake., Methods: Participants were men (n = 238) and women (n = 458) aged 20-29 years. A subset (n = 95) with body mass index (BMI) data available completed a sensory analysis study. A food frequency questionnaire assessed dietary intake, and eight polymorphisms were genotyped (rs12033832, rs12137730, rs35874116, rs3935570, rs4920564, rs4920566, rs7513755 and rs9701796). Sucrose taste thresholds were determined by staircase procedure (solutions: 9 × 10-6 to 0.5 mol/l). Suprathreshold sensitivity to 0.01-1.0 mol/l sucrose solutions was assessed using general Labeled Magnitude Scales., Results: A significant genotype-BMI interaction was observed for rs12033832 (G>A) for suprathreshold sensitivity (p = 0.01) and sugar intake (p = 0.003). Among participants with a BMI ≥25, G allele carriers had lower sensitivity ratings (mean incremental area under the taste sensitivity curve ± SE; GG/GA 54.4 ± 4.1 vs. AA 178.5 ± 66.6; p = 0.006), higher thresholds (GG/GA 9.3 ± 1.1 vs. AA 4.4 ± 4.3 mmol/l; p = 0.004) and consumed more sugars (GG/GA 130 ± 4 vs. AA 94 ± 13 g/day; p = 0.009). G allele carriers with a BMI <25 had lower thresholds (GG/GA 8.6 ± 0.5 vs. AA 16.7 ± 5.7 mmol/l; p = 0.02) and consumed less sugars (GG/GA 122 ± 2 vs. AA 145 ± 8 g/day; p = 0.004)., Conclusion: The rs12033832 single nucleotide polymorphism in TAS1R2 is associated with sucrose taste and sugar intake, but the effect differs depending on BMI., (© 2015 S. Karger AG, Basel.)

The objective of this study was to determine whether single nucleotide polymorphisms (SNPs) in the SCNN1A (3), SCNN1B (12), SCNN1G (6), and TRPV1 (10) genes affect salt taste perception. Participants were men (n = 28) and women (n = 67) from the Toronto Nutrigenomics and Health study aged 21-31 years. Taste thresholds were determined using a 3-alternative forced-choice staircase model with solutions ranging from 9×10(-6) to 0.5 mol/L. Suprathreshold taste sensitivity to 0.01-1.0 mol/L salt solutions was assessed using general labeled magnitude scales. None of the SNPs in the SCNN1A and SCNN1G genes were significantly associated with either outcome. In the SCNN1B gene, 2 SNPs in intronic regions of the gene modified suprathreshold taste sensitivity (mean iAUC ± SE). Those homozygous for the A allele of the rs239345 (A>T) polymorphism and the T allele of the rs3785368 (C>T) polymorphism perceived salt solutions less intensely than carriers of the T or C alleles, respectively (rs239345: 70.82±12.16 vs. 96.95±3.75, P = 0.02; rs3785368: 57.43±19.85 vs. 95.57±3.66, P = 0.03) In the TRPV1 gene, the rs8065080 (C>T, Val585Ile) polymorphism modified suprathreshold taste sensitivity where carriers of the T allele were significantly more sensitive to salt solutions than the CC genotype (98.3±3.8 vs. 74.1±8.3, P = 0.008). Our findings show that variation in the TRPV1 and the SCNN1B genes may modify salt taste perception in humans.

For a number of biomedical applications, including the development of phantoms for quality control of radiotherapy treatments and dose determination, it is important to study the radiation response of the used materials, in order to distinguish the relevant dose distribution modifications from the artifacts caused by the phantom material when subjected to high dose irradiation. Beside the radiation response, those materials should have certain physical and chemical properties in order to be able to be used for the purposes described above, i.e., mechanical hardness and inelasticity, chemically stability and nonreactive, among others. In this work, a wide range of polymeric materials were irradiated under megavoltage radiation using a radiotherapy linear accelerator. The irradiated materials were imaged using transmission X-ray tomography to determine if some radiation induced electronic density change could result in altered Hounsfield units. Furthermore, Raman Spectroscopy and X-ray Diffraction (XRD) techniques were used before and after irradiation in order to study any structural modification induced by the radiation. In addition, a special phantom simulating a breast treatment with two tangential beams has been fabricated and tested.

Background: A novel method to measure 1,25-dihydroxyvitamin D (1,25(OH)(2)D) in human tissue was developed and validated. The objectives of this study were to determine whether 1,25(OH)(2)D is present in human colon tissue and to characterize the relationship between human colon tissue and serum 1,25(OH)(2)D concentrations., Materials and Methods: Normal colon tissue specimens and matched serum samples were obtained from 30 patients who had undergone colectomy. Colon 1,25(OH)(2)D was measured by lipid extraction followed by enzyme immunoassay (EIA). Serum 1,25(OH)(2)D and 25-hydroxyvitamin D (25(OH)D) were measured by EIA. Vitamin D binding protein (DBP) was measured in a subset of serum and tissue samples., Results: Regression analysis indicated a significant positive correlation between serum and colon 1,25(OH)(2)D concentrations (r=0.58, p=0.0008). The corresponding intercept at zero serum 1,25(OH)(2)D was 21.5 pmol/kg (95% CI=16.95-25.98; p<0.001). Colon 1,25(OH)(2)D did not correlate significantly with serum 25(OH)D. DBP levels in tissue samples were negligible., Conclusion: The hormone 1,25(OH)(2)D can be successfully detected in human colon at physiologically relevant concentrations, partly determined by serum 1,25(OH)(2)D. The results support the notion of in vivo synthesis of 1,25(OH)(2)D within colon tissues.

Background: Preclinical studies indicate a role of Korean red ginseng (KRG) in the modulation of vascular function; however, clinical evidence is scarce. Therefore, the objective of this study was to investigate the effect of KRG root on peripheral blood pressure (BP) and augmentation index (AI), an emerging method to assess cardiovascular risk beyond conventional BP measurements. Furthermore, in an attempt to elucidate which of the major components of KRG is responsible for these effects, the ginsenoside and polysaccharide fractions isolated from the same KRG root were also investigated., Methods: The study was designed as an acute randomized, controlled, double blind, crossover trial. A total of 17 healthy fasted individuals (gender: 9 males:8 females, age: 30 +/- 9 years, body mass index: 25 +/- 3 kg/m(2), systolic BP (SBP): 110 +/- 10.1, diastolic BP (DBP): 65 +/- 7 mm Hg) received, on separate occasions, four treatments consisting of: 3 g of either placebo, KRG root, or a KRG root bioequivalent dose of ginsenoside or polysaccharide fractions. BP and AI were measured by applanation tonometry at baseline, 1, 2, and 3 h post-treatment., Results: Compared to placebo, 3 g of KRG significantly lowered radial AI by 4.6% (P = 0.045), whereas the ginsenoside fraction comparably decreased AI by 4.8% (P = 0.057), and no effect was observed with the polysaccharides. There were no differences in BP between treatments., Conclusion: Although preliminary, this study is the first to demonstrate that KRG may improve arterial stiffness as measured by AI. In addition, it appears that ginsenosides may be the principal pharmacologically active component of the root, rather than the polysaccharide fraction. This study supports the results seen with KRG in the preclinical studies and warrants further investigation on acute and long-term endothelial parameters.

Background: The prevalence of the metabolic syndrome (MetS) is increasing worldwide and prevention represents a major challenge. Usually identified in middle age, the MetS has pediatric roots and there are variable incidence rates between ethnic groups. Due to the difficulty of diagnosis, it remains largely undetected in adolescents., Objectives: To assess the presence of the MetS features in healthy, normal-weight, multiethnic adolescents and to determine whether fasting blood glucose (FBG) could function as a simple indicator of its presence., Methods: A convenience sample of secondary school students was used in a cross-sectional study. General linear model ANCOVA adjusted for multiple pairwise comparisons by the post hoc Tukey-Kramer test was used to assess differences among the tertiles of FBG., Results: A total of 182 adolescents from 62 Greater Toronto Area secondary schools in Ontario were recruited (44% Caucasian, 34% South Asian and 22% Chinese), with a mean (+/- SD) age of 17.4+/-0.9 years, a mean body mass index of 22.1+/-3.4 kg/m2 and a mean FBG of 4.92+/-0.4 mmol/L. Analysis with general linear model ANCOVA across the tertiles of FBG (3.83 mmol/L to 4.78 mmol/L, 4.79 mmol/L to 5.08 mmol/L, and 5.09 mmol/L to 6.45 mmol/L) showed significant linear increases of body mass index (P<0.005), waist circumference (P<0.001), systolic blood pressure (P<0.001) and diastolic blood pressure (P<0.05) with increasing FBG. Stepwise multiple regression analysis indicated systolic blood pressure (beta=0.0078, partial R2=0.039, P=0.007) and waist circumference (beta=0.0081, partial R2=0.025, P=0.035) were independent predictors of the increased FBG level., Conclusions: MetS markers were present in a sample of healthy multiethnic adolescents in the Greater Toronto Area. FBG could be used as a simple indicator of the MetS to allow for early detection of the presence of the MetS and the introduction of preventive lifestyle measures. Further studies with larger sample sizes should address the accuracy of FBG for diagnosing the MetS.

N-alquil nitrones 1c and 3-6 were prepared from aromatic aldehydes and N-tert-butylhydroxylamine or N-methylhydroxylamine in good yields and soft conditions. Their protective effect against microvascular damages caused by ischemia/reperfusion in 'hamster cheek pouch' assay was investigated and compare with that observed for nitrones 1a,b and 2, previously studied. Nitrones 3b, 4b and 4c were the most active ones in inhibiting macromolecular permeability increase induced by ischemia/reperfusion when administered by gavage and intravenous, while 3a and 4a were active only after intravenous administration. N-tert-butylhydroxylamine and Nt-methylhydroxylamine, products of the hydrolysis of these nitrones, were weakly active when administered by gavage or intravenous. Nitrone (4a) was the most potent in inhibiting macromolecular permeability increase induced by histamine. In this case, N-tert-butylhydroxylamine was as active as 4a. The lypophylicity in nitrones, specially in N-methyl nitrones, play an important role on the protective action when compounds were administered by gavage.

Nanocrystalline diamond (NCD) has a great potential for prosthetic implants coating. Nevertheless, its biocompatibility still has to be better understood. To do so, we employed several materials characterization techniques (SEM, AFM, micro-Raman spectroscopy) and cell culture assays using MG63 osteoblast-like and human bone marrow cells. Biochemical routines (MTT assays, Lowry's method, ALP activity) supported by SEM and confocal microscopy characterization were carried out. We used silicon nitride (Si3N4) substrates for NCD coatings based on a previous demonstration of the superior adhesion and tribological performance of these NCD coated ceramics. Results demonstrate an improved human osteoblast proliferation and the stimulation of differentiated markers, like ALP activity and matrix mineralization, compared with standard polystyrene tissue culture plates. The nanometric featuring of NCD, associated to its chemical affinity are key points for bone regeneration purposes.

Two synthetic calcium phosphates in porous wedge shape, Bonelike and a commercial HA/beta-TCP biphasic material, were used as an alternative to bone autografts and allografts in the treatment of medial compartment osteoarthritis of varus knees. The structure of Bonelike has a 3D architecture that is computer controlled, and a composition that mimics the mineral composition of natural bone. The HA/beta-TCP biphasic material used as a control material in this study was prepared using conventional foaming based methods. No signs of inflammatory reactions were observed post-operatively for both materials. After 4 months signs of fusion at the osteotomy site and good integration of the implanted wedges were observed, showing good mechanical resistance. Concerning the final correction attained, the left knee revealed a satisfactory valgus of 10 degrees , but the right one only had a final value of 6 degrees . The clinical evaluation using International Knee Score (IKS) showed good outcome in all parameters with complete range of motion in both knees and climbing stairs without crutches with only slight pain.

Nitrones 4-7, structurally related to PBN (1), were prepared by reaction of the corresponding aromatic aldehydes with N-tert-butyl hydroxylamine. The protective effects of these nitrones against microvascular damages in ischemia/reperfusion in the 'hamster cheek pouch' assay were studied and 1, as well as 4a, 4b, and 7 (derived from piperonal, O-benzyl vanillin, and furfural, respectively), showed to be more active than shark cartilage or alpha-tocopherol. No correlation was found between the protective effect of these nitrones and their logP (partition coefficient) or their capacity to trap (*)OH and (*)CH(3) radicals.

The aim of this work was to evaluate the in vitro degradation behaviour of a 45CaO-37P(2)O(5)-5MgO-13TiO(2) (mol.%) glass ceramic, under two different simulated physiological conditions: normal physiological pH 7.4, and pH 3.0, which was designed to simulate the acidic conditions produced by osteoclast cells. The in vitro testing was carried out at 37 degrees C for up to 42 days for the pH 7.4 solution and for up to 1 day for the pH 3.0 solution. The incorporation of TiO(2) into the glass structure leads to the precipitation of specific crystalline phases in the glass matrix, namely alpha- and beta-Ca(2)P(2)O(7), TiP(2)O(7) and CaTi(4)(PO(4))(6). The degradation testing at pH 3.0 showed a higher weight loss compared with degradation testing at pH 7.4; the weight loss under the acidic condition after 1 day (24 h) was about 10 times higher than the weight loss after 42 days of immersion at pH 7.4. The ionic release profile of Ca(2+), PO(4)(3-), Mg(2+) and Ti(4+) showed a continuous increase in concentration over all immersion times for both testing solutions. After 1 day of immersion at pH 3.0, the concentration levels of Mg(2+), Ca(2+), PO(4)(3-) were about six times higher than the levels achieved after 42 days of immersion at pH 7.4. The glass ceramic showed similar degradation to hydroxyapatite, and therefore has potential to be used in certain clinical applications where relatively slow resorption of the implant and replacement by bone is required, e.g. cranioplasty.

Two MK5 (45CaO-45P(2)O(5)-5MgO-5K(2)O, in mol%) and MT13 (45CaO-37P(2)O(5)-5MgO-13TiO(2), in mol%) glasses are prepared in the meta- and pyrophosphate regions and crystallized to obtain MK5B and MT13B, respectively. MK5B was obtained by controlled crystallization, and MT13B by powder sintering. As a result of these heat treatment processes, the crystalline phases precipitated in the glassy matrix are KCa(PO(3))(3), beta-Ca(PO(3))(2), beta-Ca(2)P(2)O(7) and Ca(4)P(6)O(19) phases for MK5B and CaTi(4)(PO(4))(6), TiP(2)O(7), alpha- and beta-Ca(2)P(2)O(7) phases for MT13B. To assess the in vivo biological behavior of these glass ceramics, a mixed granulometry in the range 250-355 mum and 355-425 mum with a ratio of 1/1 was implanted for 2, 4, and 12 weeks in the tibiae of Japanese white rabbits. The results showed that the in vivo behavior was strongly affected by their solubility. All implanted materials, MK5B and MT13B, and beta-tricalcium phosphate (beta-TCP) as control material, showed signs of degradation in vivo. However, the levels of degradation were quite different throughout the implantation periods. The highest degradation was observed for MK5B glass ceramic and the lowest for MT13B with beta-TCP in-between. All implanted materials allow for new bone formation in the bone defect area. At the longest implantation period (12 weeks), the MT13B and beta-TCP materials were almost completely surrounded by new bone tissue, whereas MK5B showed some unfilled spaces. This behavior is discussed in terms of the high degradation observed in previous studies.

Two glass ceramics in the CaO--P2O5--MgO system with the incorporation of K2O or TiO2 oxides were prepared with the goal of using them as potential bone graft substitutes. The incorporation of TiO2 and K2O led to the preparation of specific crystalline phases in the structure of the glass ceramics, which show different degrees of biodegradation. In fact, the 45CaO--45P2O5--5MgO--5K2O has been previously demonstrated to be much more soluble in aqueous solutions than the 45CaO--37P2O5--5MgO--13TiO2 glass ceramic. The in vitro biological activity of the two calcium phosphate glass ceramics was studied with the use of human bone marrow osteoblast cell cultures maintained for 28 days, and seeded materials were assessed for cell proliferation and function. The Ti-containing glass ceramic showed a stable surface throughout the culture time, on macroscopic and SEM observation. Osteoblast cells proliferated gradually, especially during the third week, with a high alkaline phosphatase activity and formation of a mineralized matrix. On SEM observation, attached cells appeared with a spread-polygonal morphology typical of the osteoblast cells, with extensive cell-to-cell contact. Cell behavior on the seeded material was similar to that found on cultures performed on tissue-culture-grade polystyrene; except for the presence of lower cell numbers during the first 2 weeks. By contrast, the K-containing glass ceramic showed a highly instable surface with dissolution/precipitation processes occurring throughout the culture time. Few cells adhered to the material surface, and subsequent proliferation was also hindered, especially from the first week onwards. Cell numbers were significantly lower than those observed in the Ti-containing glass ceramic during most of the incubation time. Results suggest that the different in vitro biological behavior of these two glass ceramics is mainly due to the significant differences in the surface degradation rate, which is directly correlated to the chemical composition of the mother glass., (Copyright (c) 2005 Wiley Periodicals, Inc.)

The conjugate addition of benzylic phenylsulfonyl carbanions (2a'-d') to enoates derived from d-(+)-mannitol (E- or Z-1a-c) was studied using THF and THF/HMPA as solvent. Under kinetic conditions (-78 degrees C), enoate E-1a,b led to a mixture of syn-(R,S) and anti-(S,S) adducts (55/45), and syn-(R,S) adducts were the main product obtained ( approximately 90/10) from enoate Z-1a. Under thermodynamic conditions (-78 degrees C to room temperature) syn-(R,S) adducts were also preferentially formed ( approximately 90/10), despite the geometry at the double bond in the acceptor. Enoate 1c (E/Z = 57/43), bearing an additional benzyl group at the alpha-position, also reacted with carbanions 2'a,b, under thermodynamic conditions, leading to syn-adducts in excellent de (control at the three newly generated stereogenic centers). The adducts were quantitatively transformed into the corresponding beta-gamma-disubstituted gamma-butyrolactones and alpha,beta,gamma-trisubstituted gamma-butyrolactones. (1)H NMR studies (NOE and J-coupling) of these lactones allowed us to determine their configuration at the newly generated chiral centers. The reduction of the C-S bond in adducts syn-(R,S) with Na/Hg, followed by treatment of the resulting products in aqueous acid media, led to enantioenriched beta-benzyl-gamma-hydroxymethyl-gamma-butyrolactones. The conformational equilibrium of enoates E- and Z-1b was evaluated by theoretical calculations (ab initio, MP2/6-31G), and a mechanistic rationale was proposed to explain the observed stereoselectivities.

The knowledge and use of popular cures was investigated as part of health education project in such a way as to develop and expand the existing possibilities for critical and constructive discussion in the school within the health program. It was hoped that this would result in the retrieval and in an increase in the value attributed to information concerning this nonsystematized knowledge present in a controversial and poorly accepted form in the practices of the population. One hundred and five teachers and 162 students of the 1st to 4th grades of the four primary schools on the outskirts of Belo Horizonte were interviewed. One hundred and five of the teachers answered the questions put. Twenty-three (32.4%) of the teachers said they believed in special cures, 69 (65.7%) thought that certain diseases could be treated with homemade remedies for these, 54 (78.3%) were able to associate a particular disease with a particular medicinal plant and 15 (21.7%) prescribed a treatment without any association with a particular disease, 36 (34.3%) cited a disease without relating this to a particular herb. One hundred and one (62.3%) of the students believed that homemade remedies are effective for certain diseases. Amongst the teachers and students various diseases were mentioned as well as different symptoms and organs that can be cured by medicinal plants, roots or traditional healers. A little more than 50% of the two groups of students (1st and 2nd grade, 3rd and 4th grade) live in families who make use of traditional healers to provide alternative cures.(ABSTRACT TRUNCATED AT 250 WORDS)

A project has been developed with the objective of implanting and testing new materials and methodologies related to health education in first level schools. The present study is being performed in 4 public schools of a periferic area of Belo Horizonte, in two regions, one of high and another of low prevalence of schistosomiasis. The experimental design includes 2 experimental schools and 2 of control. The procedure involves interviews with teachers and students before and after the experimental test of the new materials; stool surveys and treatment of the sample of students. The results of the first interviews demonstrated that the knowledge of schistosomiasis is almost absent among teachers and students, although the prevalence of this disease has been maintained for a long time (70 years) in one of the regions studied (Gorduras). Out of 3131 students of the 4 schools, 67.5% were examined and 235 (11.0%) were tested positively. When the new students of 1989 were not included the prevalence decrease to 9.0% demonstrating a significative difference (X2 - 5%) in relation to 1988, showing the consequence of the treatment performed. Comparing the 2 schools of high prevalence, the decrease of prevalence of the experimental one is higher than the control. Therefore, in relation to the schools of low prevalence, the same has not happened. Thus, it is only possible to suggest an initial effect of the educative strategy and the decreases of the prevalence in the schools of high prevalence. In relation to the knowledge about the disease transmission, the students from the experimental schools presented a significative increase of correct answers in 1989 than the control ones.