What facilitates or prevents academic fraud in a Colombian faculty of medicine-Protocol of a study using fuzzy cognitive mapping.

INTRODUCTION: Academic fraud is any behavior that gives a student an undeserved advantage over another student. Few studies have explored the causes of and possible solutions to academic fraud in Latin America. We aim to map the knowledge of stakeholders in a Colombian faculty of medicine about the factors that facilitate and prevent academic fraud. METHODS: Fuzzy cognitive mapping. We will use the approach proposed by Andersson and Silver to generate fuzzy cognitive maps representing stakeholder knowledge. This process consists of ten steps: (1) definition of the research question; (2) identification of participants; (3) generation of ideas; (4) rationalization of ideas; (5) organization and connection of ideas; (6) weighing; (7) pattern grouping; (8) list of links and digitization; (9) combination of maps and network analysis; and (10) deliberative dialogue. To draw the maps, we will invite medical students, interns, resident physicians, master's students, and professors in the faculty of medicine. Four medical students will receive training to facilitate the sessions. Participants will identify the factors contributing to academic fraud and their causal relationships. We will use a combination of network analysis and graph theory to identify the chains of factors with greatest influence on academic fraud. CONCLUSION: The maps will serve to discuss strategies to reduce academic fraud in the Faculty of Medicine and to identify factors that could be addressed in other contexts with similar problems. This research will allow the students who facilitate mapping sessions to learn about research techniques, fuzzy cognitive mapping and academic fraud. Study registration: Registered in OSF Registries on August 2nd, 2022. Registration number: osf.io/v4amz.

Biowaxes from Palm Oil as Promising Candidates for Cosmetic Matrices and Pharmaceuticals for Human Use.

The production of waxes from vegetable oils, such as palm oil, for use as a base material in products for human applications is an alternative to those derived from petroleum and animals. Seven palm oil-derived waxes, called biowaxes (BW1-BW7) in this work, were obtained by catalytic hydrotreating of refined and bleached African palm oil and refined palm kernel oil. They were characterized by three properties: compositional, physicochemical (melting point, penetration value, and pH), and biological (sterility, cytotoxicity, phototoxicity, antioxidant, and irritant). Their morphologies and chemical structures were studied by SEM, FTIR, UV-Vis, and 1H NMR. The BWs presented structures and compositions similar to natural biowaxes (beeswax and carnauba). They had a high concentration of waxy esters (17%-36%) with long alkyl chains (C, 19-26) per carbonyl group, which are related to high melting points (<20-47.9 °C) and low penetration values (2.1-3.8 mm). They also proved to be sterile materials with no cytotoxic, phototoxic, antioxidant, or irritant activity. The biowaxes studied could be used in cosmetic and pharmacological products for human use.

Enhancing sparse representation of color images by cross channel transformation.

Transformations for enhancing sparsity in the approximation of color images by 2D atomic decomposition are discussed. The sparsity is firstly considered with respect to the most significant coefficients in the wavelet decomposition of the color image. The discrete cosine transform is singled out as an effective 3 point transformation for this purpose. The enhanced feature is further exploited by approximating the transformed arrays using an effective greedy strategy with a separable highly redundant dictionary. The relevance of the achieved sparsity is illustrated by a simple encoding procedure. On typical test images the compression at high quality recovery is shown to significantly improve upon JPEG and WebP formats.

Construction of wavelet dictionaries for ECG modeling.

Technical details, algorithms, and MATLAB implementation for a method advanced in the paper ``Wavelet Based Dictionaries for Dimensionality Reduction of ECG Signals'', are presented. This work aims to be the companion of that publication, in which an adaptive mathematical model for a given ECG record is proposed. The method comprises the following building blocks.(i)Construction of a suitable redundant set, called 'dictionary', for decomposing an ECG signal as a superposition of elementary components, called 'atoms', selected from that dictionary.(ii)Implementation of the greedy strategy Optimized Orthogonal Matching Pursuit (OOMP) for selecting the atoms intervening in the signal decomposition.This paper gives the details of the algorithms for implementing stage (i), which is not fully elaborated in the previous publication. The proposed dictionaries are constructed from known wavelet families, but translating the prototypes with a shorter step than that corresponding to a wavelet basis. Stage (ii) is readily implementable by the available function OOMP.•The use of the software and the power of the technique is illustrated by reducing the dimensionality of ECG records taken from the MIT-BIH Arrhythmia Database.•The MATLAB software has been made publicly available on a dedicated website.•We provide the explanations, algorithms and software for the construction of scaling functions and wavelet prototypes for 17 different wavelet families. The procedure is designed to allow for straightforward extension of the software by the inclusion of additional options for the wavelet families.

Effective high compression of ECG signals at low level distortion.

An effective method for compression of ECG signals, which falls within the transform lossy compression category, is proposed. The transformation is realized by a fast wavelet transform. The effectiveness of the approach, in relation to the simplicity and speed of its implementation, is a consequence of the efficient storage of the outputs of the algorithm which is realized in compressed Hierarchical Data Format. The compression performance is tested on the MIT-BIH Arrhythmia database producing compression results which largely improve upon recently reported benchmarks on the same database. For a distortion corresponding to a percentage root-mean-square difference (PRD) of 0.53, in mean value, the achieved average compression ratio is 23.17 with quality score of 43.93. For a mean value of PRD up to 1.71 the compression ratio increases up to 62.5. The compression of a 30 min record is realized in an average time of 0.14 s. The insignificant delay for the compression process, together with the high compression ratio achieved at low level distortion and the negligible time for the signal recovery, uphold the suitability of the technique for supporting distant clinical health care.

Anti-leishmanial activity of a topical miltefosine gel in experimental models of New World cutaneous leishmaniasis.

OBJECTIVES: Topical treatment for cutaneous leishmaniasis (CL) would be useful for treatment of some forms of the disease. The aim of this study was to develop and then evaluate a topical miltefosine gel for anti-leishmanial activity and toxicity in BALB/c mice infected with New World (NW)-CL species. METHODS: A Carbopol-based gel of 0.5% miltefosine was prepared and physicochemical (colour, pH, consistency and antioxidant activity) and stability properties were determined using standard methodologies. Anti-leishmanial activities for Leishmania (Viannia) braziliensis and Leishmania (Viannia) panamensis were determined both in cultured parasites and in infected BALB/c mice after topical miltefosine gel treatment administered for 20 days. The gel was evaluated for its capacity to inhibit parasites at a 50% level after 3 days of treatment in vitro, and its capacity to reduce lesion size (mm2) and parasitic load after 20 days of treatment. Dermal irritation, contact hypersensitivity (CHS), clinical biochemical profile and the weight of the animals were determined after treatment. RESULTS: The 0.5% miltefosine gel was transparent, homogeneous, colourless, of neutral pH, spreadable and stable at 4°C for at least 3 months. It was active against parasites in vitro and in vivo, reducing CL lesion size by 84%-100% with no detected parasites. No signs of irritation, CHS or changes in weight, food intake, urea or transaminase serum levels were observed after treatment. CONCLUSIONS: The topical 0.5% miltefosine gel formulation was efficacious and non-toxic when administered topically in NW-CL murine models. This miltefosine formulation could be an appropriate candidate for further development.

Leishmaniasis cutánea inducida por especies de leishmanial Viannia en ratones BALB/c y eficacia de un tratamiento tópico / Cutaneous leishmaniasis by Leishmania Viannia species in BALB/c mice and efficacy of a topical treatment

Resumen Introducción: La diversidad de las formas clínicas de la leishmaniasis del Nuevo Mundo (desde formas cutáneas localizadas a diseminadas o formas mucosas) causada por especies del subgénero Viannia podría inferir en la eficacia de los tratamientos tópicos. El objetivo del presente trabajo fue determinar las características de la leishmaniasis cutánea producida por infecciones con Leishmania (V.) braziliensis y L.(V.) panamensis en ratones BALB/c y la eficacia de un mismo tratamiento tópico. Materiales y métodos: Después de la infección con cada una de las especies se realizó seguimiento de las lesiones determinando su tamaño (mm ) y características macroscópicas, cada siete días por 150 días. Las características histopatológicas (en lesiones y órganos) fueron determinadas 70, 106 y 150 días post-infección y la eficacia de un tratamiento tópico (cura de lesión y parasitológica) fue determinada después del tratamiento con un gel de miltefosina aplicado una vez al día por 20 días sobre las lesiones. Resultados: Se observó un aumento del tamaño de las lesiones en ambos grupos de ratones, sin embargo, un mayor tamaño de las lesiones e intensidad de la respuesta inflamatoria con menos alteraciones epidérmicas fue encontrada en los ratones infectados con L. (V.) braziliensis. En ningún grupo se encontraron parásitos en órganos (nódulos, bazo e hígado) ni diferencias en la efectividad del tratamiento tópico utilizado. Conclusión: La eficacia del tratamiento tópico utilizado no fue afectada por las diferencias macro y microscópicas encontradas en la leishmaniasis producida por las dos especies de Leishmania evaluadas.

Abstract Introduction: The efficacy of topical treatments could be affected by the diversity of clinical forms (localized or disseminated cutaneous forms, mucosal forms) of New World-leishmaniasis caused by species of Leishmania from the subgenus Viannia. The aim of this study was to determine the cutaneous leishmaniasis features produced after infection with Leishmania (V.) braziliensis and L. (V.) panamensis in BALB/c mice and to determine the efficacy of one topical treatment. Materials and methods: Cutaneous leishmaniasis lesions were followed up after infection determining their lesion-size (mm2) and other macroscopic characteristics every 7 days for 150 days. Histopathological patterns (in lesions and organs) were determined 70, 106 and 150 days post-infection and the efficacy (lesion and parasitological cure) of miltefosine gel applied topical once a day for 20 days was determined. Results: An increase of size-lesions was observed in both groups of mice, however, a higher lesion- size and inflammatory response but lower epidermal changes were observed in L. (V.) braziliensis compared with L. (V.) panamensis infected ones. No parasites were observed in organs (nodules, spleen and liver) and no differences were observed in the effectiveness of the used topical treatment. Conclusion: The efficacy of the topical treatment used was not affected by the macro and microscopic differences produced after infection by the two Leishmania species evaluated.

Photodynamic therapy using ultradeformable liposomes loaded with chlorine aluminum phthalocyanine against L. (V.) braziliensis experimental models.

Ultradeformable liposomes (UDLs) containing sodium cholate as edge activator could be an appropriate skin drug-delivery system for chloroaluminum phthalocyanine (ClAlPc) during photodynamic therapy (PDT) against cutaneous leishmaniasis (CL). The aim of this work was to study cell internalization, reactive oxygen species (ROS) production, and toxicity/genotoxicity and transdermal delivery of UDL-ClAlPc, and to determine whether PDT was able to induce anti-leishmanial activity in Leishmania (Viannia) braziliensis experimental models. Prepared liposomes had an average size of 118.39 nm, zeta potential of -37.83 mV, and polydispersity index of 0.15. Liposomal internalization (red fluorescence inside cells), ROS generation (green fluorescence by 2,7-dichlorodihydrofluorescein diacetate [DCFH-DA] cleavage) and non-specific DNA damage (photo-comets) were observed after PDT. Transdermal delivery of ClAlPc, measured by in vitro diffusion experiments through BALB/c skin, showed that UDL-ClAlPc was able to deliver very low quantities of ClAlPc (<1%) to deep skin layers. PDT using UDL-ClAlPc induced photodamage in mammalian cells (J774, THP-1, and NIH-3T3), promastigotes, and intracellular amastigotes without a selective response against amastigotes (selective index ≥1). Topical once-daily ClAlPc-UDL plus visible-light irradiation (20 J/cm2) twice weekly for 3 weeks was ineffective against L. (V.) braziliensis-infected BALB/c mice, whereas miltefosine 30 mg/kg/day orally for 10 days healed the lesions and scars, without parasites observed on the slides. Even though UDLs preserved ClAlPc photoactivities and were able to deliver ClAlPc to dermis, they were unable to result in healing of CL-infected mice after PDT. Experiments using different CL animal models and liposomes with increased skin permeability abilities are recommended.

A competitive scheme for storing sparse representation of X-Ray medical images.

A competitive scheme for economic storage of the informational content of an X-Ray image, as it can be used for further processing, is presented. It is demonstrated that sparse representation of that type of data can be encapsulated in a small file without affecting the quality of the recovered image. The proposed representation, which is inscribed within the context of data reduction, provides a format for saving the image information in a way that could assist methodologies for analysis and classification. The competitiveness of the resulting file is compared against the compression standards JPEG and JPEG2000.

Toxicidad, genotoxicidad y actividad anti-Leishmania de aceites esenciales obtenidos de cuatro (4) quimiotipos del género Lippia / Toxicity, genotoxicity and anti-Leishmania activity of essential oils obtained of four chemotypes of Lippia genus

Los aceites esenciales (AEs), pertenecientes al género Lippia, son candidatos interesantes de formulaciones tópicas en el tratamiento de la leishmaniasis cutánea (LC). El objetivo de este trabajo fue determinar el perfil toxicológico y la actividad anti-Leishmania de AEs obtenidos de plantas colombianas del género Lippia. Ratones BALB/c fueron tratados tópica u oralmente con AEs obtenidos de L. alba quimiotipo citral (AE1) y de L. origanoides quimiotipos timol (AE2), carvacrol (AE3) y felandreno (AE4). El efecto del tratamiento en la irritación de la piel, la toxicidad aguda oral, la genotoxicidad (prueba cometa y micronúcleos), los cambios en la función hepática y renal, la inducción de reacción de hipersensibilidad de contacto y en la actividad contra L. (V) panamensis y L. (V.) braziliensis fueron determinados. Todos los AEs presentaron un perfil toxicológico similar a los parámetros normales, exceptuando los aceites AE2 y AE3 los cuales fueron irritantes y presentaron algunos signos de toxicidad aguda oral al ser utilizados en altas concentraciones (concentraciones bajas no fueron tóxicas). El AE2 mostró actividad antiparasitaria en las formas parasitarias evaluadas. Concentraciones bajas de los AEs podrían utilizarse de forma segura como componentes de formulaciones farmacológicas en LC.

Essential oils (EOs) belonging to the genus Lippia are interesting candidates in pharmaceutical systems for cutaneous leishmaniasis (CL). The aim of this work was to determine both toxicological and antileishmanial activities of EOs obtained from different species of Lippia, a widely distributed Colombian plants. BALB/c mice were treated topically or orally with EOs obtained from L. alba citral chemotype (EO1) and L. origanoides thymol (EO2), carvacrol (EO3) and phellandrene (EO4) chemotypes. The skin irritation, oral acute toxicity, genotoxicity (comet assay and micronucleus test), liver and renal adverse effects, All the EOs showed a toxicological profile similar to the normal parameters, except for oils EO2 and EO3 which were irritant and showed some signs of acute oral toxicity at high concentrations (low concentration were safe). The EO2 showed antiparasitic activity. Low concentrations of the EO could be used safely as components of pharmacological formulations in CL.

Effective sparse representation of X-ray medical images.

Effective sparse representation of X-ray medical images within the context of data reduction is considered. The proposed framework is shown to render an enormous reduction in the cardinality of the data set required to represent this class of images at very good quality. The goal is achieved by (1) creating a dictionary of suitable elements for the image decomposition in the wavelet domain and (2) applying effective greedy strategies for selecting the particular elements, which enable the sparse decomposition of the wavelet coefficients. The particularity of the approach is that it can be implemented at very competitive processing time and low memory requirements.

A dedicated greedy pursuit algorithm for sparse spectral representation of music sound.

A dedicated algorithm for sparse spectral representation of music sound is presented. The goal is to enable the representation of a piece of music signal as a linear superposition of as few spectral components as possible, without affecting the quality of the reproduction. A representation of this nature is said to be sparse. In the present context sparsity is accomplished by greedy selection of the spectral components, from an overcomplete set called a dictionary. The proposed algorithm is tailored to be applied with trigonometric dictionaries. Its distinctive feature being that it avoids the need for the actual construction of the whole dictionary, by implementing the required operations via the fast Fourier transform. The achieved sparsity is theoretically equivalent to that rendered by the orthogonal matching pursuit (OMP) method. The contribution of the proposed dedicated implementation is to extend the applicability of the standard OMP algorithm, by reducing its storage and computational demands. The suitability of the approach for producing sparse spectral representation is illustrated by comparison with the traditional method, in the line of the short time Fourier transform, involving only the corresponding orthonormal trigonometric basis.

Sarcoidosis sistémica: un reto diagnóstico en pediatría. Reporte de un caso / Systemic sarcoidosis: a diagnostic challenge in pediatrics. Case report

La sarcoidosis es una enfermedad inflamatoria granulomatosa de etiología desconocida, evidenciada con mayor frecuencia en adultos jóvenes, que puede comprometer diversos órganos, principalmente, el pulmón, los ganglios linfáticos, los ojos y la piel. La presencia de dicha enfermedad enla población pediátrica es poco frecuente y su denominación en pediatría se realiza basada en la edad y las manifestaciones clínicas del paciente. El objetivo del siguiente reporte es presentar un caso de sarcoidosis sistémica en un paciente adolescente sin compromiso pulmonar, con manifestaciones extrapulmonares graves. Se trata de un paciente de 15 años, quien debutó con síntomas inespecíficos (emesis, pérdida de peso). Estudios radiológicos, sin compromiso pulmonar aparente; sin embargo, con presencia de hallazgos sugestivos de histiocitosis de células de Langerhans. Se realizó un estudio histopatológico de componente óseo y linfático, cuyo resultado evidenció la presencia de una enfermedad granulomatosa crónica no necrotizante tipo sarcoidosis. La sarcoidosis infantil es una entidad rara y difícil de diagnosticar, dada, principalmente, la ausencia de biomarcadores específicos para su diagnóstico.

Sarcoidosis is a granulomatous inflammatory disease of unknown etiology, evidenced most often in young adults, which can compromise several organs, mainly lung, lymph nodes, eyes and skin. The presence of the disease in pediatric population is rare. Denomination in pediatrics is made based on age and clinical manifestations of the patient. The aim of this report is to present a case of systemic sarcoidosis in a pediatric patient without lung involvement with severe extrapulmonary manifestations. Fifteen year old patient who debuted with nonspecific symptoms (emesis, weight loss). Radiographic studies without lung involvement but with findings suggestive of Langerhans cell histiocytosis; however, histopathological report (bone and lymph) showed the presence of chronic granulomatous nonnecrotizing disease, sarcoidosis type. Childhood sarcoidosis is a rare and difficult entity to diagnose, mainly by the lack of specific biomarkers for diagnosis.

[Systemic sarcoidosis: a diagnostic challenge in pediatrics. Case report]. / Sarcoidosis sistémica: un reto diagnóstico en pediatría. Reporte de un caso.

Sarcoidosis is a granulomatous inflammatory disease of unknown etiology, evidenced most often in young adults, which can compromise several organs, mainly lung, lymph nodes, eyes and skin. The presence of the disease in pediatric population is rare. Denomination in pediatrics is made based on age and clinical manifestations of the patient. The aim of this report is to present a case of systemic sarcoidosis in a pediatric patient without lung involvement with severe extrapulmonary manifestations. Fifteen year old patient who debuted with nonspecific symptoms (emesis, weight loss). Radiographic studies without lung involvement but with findings suggestive of Langerhans cell histiocytosis; however, histopathological report (bone and lymph) showed the presence of chronic granulomatous nonnecrotizing disease, sarcoidosis type. Childhood sarcoidosis is a rare and difficult entity to diagnose, mainly by the lack of specific biomarkers for diagnosis.

La sarcoidosis es una enfermedad inflamatoria granulomatosa de etiología desconocida, evidenciada con mayor frecuencia en adultos jóvenes, que puede comprometer diversos órganos, principalmente, el pulmón, los ganglios linfáticos, los ojos y la piel. La presencia de dicha enfermedad enla población pediátrica es poco frecuente y su denominación en pediatría se realiza basada en la edad y las manifestaciones clínicas del paciente. El objetivo del siguiente reporte es presentar un caso de sarcoidosis sistémica en un paciente adolescente sin compromiso pulmonar, con manifestaciones extrapulmonares graves. Se trata de un paciente de 15 años, quien debutó con síntomas inespecíficos (emesis, pérdida de peso). Estudios radiológicos, sin compromiso pulmonar aparente; sin embargo, con presencia de hallazgos sugestivos de histiocitosis de células de Langerhans. Se realizó un estudio histopatológico de componente óseo y linfático, cuyo resultado evidenció la presencia de una enfermedad granulomatosa crónica no necrotizante tipo sarcoidosis. La sarcoidosis infantil es una entidad rara y difícil de diagnosticar, dada, principalmente, la ausencia de biomarcadores específicos para su diagnóstico.

Functional properties and in vitro antioxidant and antibacterial effectiveness of pigskin gelatin films incorporated with hydrolysable chestnut tannin.

The impact of the incorporation of 10% w/w of hydrolyzable chestnut tannin into pigskin gelatin (G) films plasticized with glycerol (Gly) on the physicochemical properties as well as the in vitro antioxidant and antibacterial effectiveness against food-borne pathogens such as Escherichia coli and Streptococcus aureus was investigated. A higher tendency to both redness (a*) and yellowness (b*) coloration characterized gelatin films incorporated with chestnut tannin. The reduced lightness (L) and transparency of gelatin-chestnut tannin films plasticized with 30% w/w Gly might be associated with certain degree of phase separation which provoked the migration of the plasticizer to the film surface. The incorporation of chestnut tannin and glycerol affected the chemical structure of the resultant films due to the establishment of hydrogen interactions between components as revealed by Fourier transform infrared spectroscopy. These interactions reduced gelatin crystallinity and seemed to be involved in the substantial decrease of the water uptake of films with tannin, irrespective of the glycerol level. Such interactions had minor effect on tensile properties being similar to those of the control films (without chestnut tannin) at the same glycerol level. Films modified with 10% w/w chestnut tannin showed significant (P < 0.05) 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity, ca. from 0 ± 0.033 to 87.1 ± 0.002% for chestnut tannin-free and chestnut tannin-containing gelatin films. The limited inhibitory activity of films incorporated with 10% w/w chestnut tannin against the selected bacteria evidenced by disk diffusion method probably resulted from the interactions within the film restricting the diffusion of the active agent into the agar medium. The more modest protective effect observed against a Gram-positive bacterium (S. aureus) was also discussed.

Actividad antiparasitaria de extractos de plantas colombianas de la familia Euphorbiaceae

Introducción: La familia Euphorbiaceae es un grupo heterogéneo de plantas distribuidas en el territorio colombiano utilizadas algunas de ellas, como plantas medicinales. Objetivo: Determinar la actividad tóxica de aceites esenciales (AE) y extractos de plantas obtenidos de la familia Euphorbiaceae contra tripanosomátidos. Materiales y métodos: Los AE de Croton pedicellatus Kunth (AE1) y C.leptostachyus Kunth (AE2) y el extracto de Phyllanthus acuminatus Vahl fueron obtenidos por hidrodestilación asistida por la radiación de microondas y maceración con metanol; se caracterizaron por cromatografía de gases acoplada a espectrometría de masas. Fueron evaluados contra las formas extracelulares e intracelulares de Trypanosoma cruzi, Leishmania (Viannia) panamensis, L. (V.) braziliensis y células Vero y THP-1. La actividad antiparasitaria fue determinada por recuento microscópico y el efecto tóxico en células por la prueba colorimétrica de MTT. Los resultados fueron expresados como la concentración que inhibe (CI50) o destruye (CC50) el 50% de parásitos o células. Resultados: Los componentes mayoritarios de los AE fueron borneol, γ-terpineno, germacreno D y trans-ß-cariofileno. Los AE1 y AE2 inhibieron el crecimiento de epimastigotes de T.cruzi y de promastigotesde L. (V.) panamensis y L. (V.) braziliensis con CI50 entre 7,14-8,78μg/mL y fueron activos contra amastigotes intracelulares de L. (V.) braziliensis (AE1:CI50 36,74 y AE2:19,77μg/mL). El extracto 1 mostró baja actividad contra los parásitos. Los AE y extractosmostraron toxicidad en células THP-1(CC50 9,29-64,12μg/mL) y células Vero (CC50 24,86-3,52μg/mL). Conclusión: Los AE obtenidos de plantas de la familia de Euphorbiaceae mostraron actividad antiparasitaria con toxicidad moderada en células de mamífero.

Introduction: The Euphorbiaceae family is a heterogeneous group of plants distributed in the Colombian territory used for medicinal proposes. Objective: To determine the toxic activity of Euphorbiaceae family essential oils and plant extract against tripanosomatides. Materials and methods: Essential oil from Croton pedicellatus Kunth (EO1) and C.leptostachyus Kunth(EO 2) and plant extract from Phyllanthus acuminatus Vahl (Ext1) were obtained by microwave-assisted hidrodistillation and characterized by gas chromatography coupled with mass spectrometry and methanol maceration. They were assessed against extracellular and intracellular forms of Trypanosoma cruzi, Leishmania(Viannia) panamensis, L.(Viannia)braziliensis and Vero and THP-1 cells. The parasite activity was determined by microscopic counting and cell toxicity by MTT colorimetric test. The results were expressed as the inhibitory (ICz50) or citotoxic (CC50) concentration for 50% of parasites or cells. Results: The EO-major components were borneol, γ-terpinene and trans-ß-caryophyllene. The EO1 and EO2 inhibited both T.cruzi-epimastigotes and L(V.) panamensis and L.(V.) brazilienses promastigotes growth with IC50 between 7.14 to 8.78 μg/mL They were active against intracellular amastigotes of L. (V.) braziliensis (EO1:IC50:36.74 and EO2:19.77μg/mL). The Ext 1 showed low activity against both parasites. The EOs and extracts were partially toxic to THP-1 (CC50 9.29 to 64.12μg/mL) and Vero cells (CC50 24.86 to 63.52μg/mL). Conclusions: The EO obtained from plants of the Euphorbiaceae family showed antiparasitic activity with some toxicity against mammalian cells.

Sparse representation of astronomical images.

Sparse representation of astronomical images is discussed. It is shown that a significant gain in sparsity is achieved when particular mixed dictionaries are used for approximating these types of images with greedy selection strategies. Experiments are conducted to confirm (i) the effectiveness at producing sparse representations and (ii) competitiveness, with respect to the time required to process large images. The latter is a consequence of the suitability of the proposed dictionaries for approximating images in partitions of small blocks. This feature makes it possible to apply the effective greedy selection technique called orthogonal matching pursuit, up to some block size. For blocks exceeding that size, a refinement of the original matching pursuit approach is considered. The resulting method is termed "self-projected matching pursuit," because it is shown to be effective for implementing, via matching pursuit itself, the optional backprojection intermediate steps in that approach.

Effect of 1,25(OH)2-vitamin D on bone mass in children with acute lymphoblastic leukemia.

BACKGROUND: Calcitriol deficit has been described in patients with acute lymphoblast leukemia (ALL). The aim of this randomized case-control trial is to investigate the effectiveness of calcitriol administration during the first year of treatment to protect bone mass. Sixteen children recently diagnosed with ALL, aged 1.7 to 11.5 years, average 5.5, completed the study. Anthropometrical measurements, food intake record, physical activity, and bone pain were registered. Dual energy x-ray absorptiometry was performed at the completion of remission induction chemotherapy (after 1 mo) to measure bone mineral density (BMD) at hip, lumbar spine and whole body, and total bone mineral content and 1 year after. Half of them were randomly assigned to receive calcitriol during 1 year. STATISTICAL: Kruskal-Wallis, Wilcoxon, Mann-Whitney, and Spearman. RESULTS: Both groups had similar anthropometric measurements and bone densitometric variables increments. Spine BMD significantly increased in calcitriol supplemented children with lower baseline BMD (r=-0.78 and P<0.05). CONCLUSIONS: One-year calcitriol administered to recently diagnosed ALL children did not show impact on bone mass. Greater increment in lumbar spine bone mass was observed in patients who received calcitriol and had lower baseline BMD.