Abstract Background Loxoscelism is a severe human envenomation caused by Loxosceles spider venom. To the best of our knowledge, no study has evaluated the presence of antibodies against Loxosceles venom in loxoscelism patients without treatment with antivenom immunotherapy. We perform a comparative analysis for the presence of antibodies capable of recognizing Loxosceles venom in a group of patients diagnosed with loxoscelism and in a group of people without loxoscelism. Methods The detection of L. laeta venom, Sicarius venom and recombinant phospholipases D from Loxosceles (PLDs) in sera from people with loxoscelism (Group 1) and from healthy people with no history of loxoscelism (Group 2) was evaluated using immuno-dot blot, indirect ELISA, and Western blot. Results We found naturally heterophilic antibodies (IgG-type) in people without contact with Loxosceles spiders or any clinical history of loxoscelism. Either serum pools or single sera from Group 1 and Group 2 analyzed by dot blot tested positive for L. laeta venom. Indirect ELISA for venom recognition showed titles of 1:320 for Group 1 sera and 1:160 for Group 2 sera. Total IgG quantification showed no difference in sera from both groups. Pooled sera and purified IgG from sera of both groups revealed venom proteins between 25 and 32 kDa and the recombinant phospholipase D isoform 1 (rLlPLD1), specifically. Moreover, heterophile antibodies cross-react with PLDs from other Loxosceles species and the venom of Sicarius spider. Conclusions People without contact with the spider venom produced heterophilic antibodies capable of generating a cross-reaction against the venom of L. laeta and Sicarius spiders. Their presence and possible interference should be considered in the development of immunoassays for Loxosceles venom detection.

In this paper we deal with the experimental synchronization of the Colpitts oscillator in a real-time implementation. Our approach is based on observer design theory in a master-slave configuration thus, a chaos synchronization problem can be posed as an observer design procedure, where the coupling signal is viewed as a measurable output and a slave system is regarded as an observer. A polynomial observer is used for synchronizing the Colpitts oscillator employing linear matrix inequalities. Finally, a comparison with a reduced order observer and a high gain observer is given to assess the performance of the proposed observer.

En este artículo se aborda la sincronización experimental del oscilador de Colpitts en tiempo real. Nuestra aproximación se realiza mediante la teoría de diseño de observadores en una configuración maestro-esclavo, por lo que el problema de sincronización caótica puede plantearse como el diseño de un observador. Se utiliza un observador polinomial para la sincronización del oscilador de Colpitts empleando desigualdades matriciales lineales. Se realiza una comparación con el observador de orden reducido y con el observador de alta ganancia con la finalidad de verificar el desempeño del observador propuesto.

FUNDAMENTO: A alta e crescente prevalência de Cardiomiopatia Dilatada (CMD) representa sério problema de saúde pública. Novas tecnologias vêm sendo utilizadas objetivando diagnósticos mais sofisticados, que melhorem a abordagem terapêutica. Nesse cenário, o Speckle Tracking (STE) utiliza marcadores miocárdicos naturais para analisar a deformação sistólica do Ventrículo Esquerdo (VE). OBJETIVO: Mensurar o strain transmural longitudinal global (SG) do VE através do STE em pacientes com CMD grave, comparando os resultados com indivíduos normais e com parâmetros ecocardiográficos consagrados para análise da função sistólica do VE, validando o método nessa população. MÉTODOS: Foram estudados 71 pacientes com CMD grave, (53 ± 12a, 72% homens) e 20 controles (30 ± 8a, 45% homens). Foram obtidos os volumes e a FEVE pela ecocardiografia bi e tridimensional, parâmetros do Doppler, Doppler tecidual e o SG pelo STE. RESULTADOS: Comparados ao grupo controle, os volumes do VE foram maiores no grupo CMD; entretanto, a FEVE e velocidade de pico da onda E foram menores neste último. O índice de performance miocárdica foi maior entre os pacientes. As velocidades do miocárdio pelo Doppler tecidual (S', e', a') foram consideravelmente menores e a relação E/e' foi maior no grupo CMD. O SG apresentou-se diminuído no grupo CMD (-5,5% ± 2,3%), em relação aos controles (-14,0% ± 1,8%). CONCLUSÃO: No presente estudo, o SG foi significativamente menor nos pacientes com CMD grave, abrindo novas perspectivas para abordagens terapêuticas nessa população específica.

BACKGROUND: The high and increasing prevalence of Dilated Cardiomyopathy (DCM) represents a serious public health problem. New technologies are being used aiming at more accurate diagnoses in order to improve therapeutic approach. In this scenario, speckle tracking echocardiography (STE) uses natural myocardial markers to analyze the systolic deformation of the left ventricle (LV). OBJECTIVE: To measure the longitudinal transmural global strain (GS) of the LV through STE in patients with severe DCM, comparing the results with normal individuals and with echocardiographic parameters established for the analysis of LV systolic function, validating the method in this population. METHODS: We studied 71 patients with severe DCM (53 ± 12 years, 72% men) and 20 controls (30 ± 8 years, 45% men). We obtained LV volumes and ejection fraction by two and three-dimensional echocardiography, Doppler parameters, tissue Doppler and GS was obtained by STE. RESULTS: Compared to controls, LV volumes were higher in the DCM group; however, LVEF and peak velocity of E wave were lower in the latter. The myocardial performance index was higher among patients. Myocardial velocities at the tissue Doppler (S', e', a') were significantly lower and E/e' ratio was higher in the DCM group. The GS was decreased in the DCM group (-5.5% ± 2.3%) when compared to controls (-14.0% ± 1.8%). CONCLUSION: In this study, GS was significantly lower in patients with severe DCM, bringing new perspectives for therapeutic approaches in this specific population.

The effect of naringin, molasses, and rhamnose, as well as calcium (Ca2+) and magnesium (Mg2+) salts on the production of naringinase by Aspergillus niger ATCC1015 was studied. The mycelial weight, protein production, and naringinase activity were quantified. The constants Vmax and Km were determined by Lineweaver-Burk. ft was found that molasses compared with the other carbon sources and the addition of calcium carbonate favored the growth of the fungus but not the production of protein or the enzyme activity. Additionally, it was found that naringin promoted 8-fold more production of protein (5684 ± 784 μg·mL-1 ) than the other carbon sources studied if Ca2+and Mg2+were added. On the other hand, rhamnose with no added salts produced 2-fold more enzyme activity than other treatments (2290 ± 157 U·mg-1). Finally, it was found that its kinetic characteristics were Vmax=13.24 U·mg-1 and Km=1.6 mM, compared with the activity of a commercial naringinase from P. decumbens (Vmax=3.96 U·mg-1 and Km=2.5 mM).

En el presente trabajo se estudió el efecto de las diferentes fuentes de carbono naringina, melaza y ramnosa, así como el efecto de la adición de las sales de calcio (Ca2+) y magnesio (Mg2+) en la producción de naringinasa por Aspergillus niger ATCC1015. Se cuantificaron el peso del micelio, la producción de proteína y la actividad de naringinasa. Las constantes Vmax y Km fueron determinadas utilizando el modelo de Lineweaver-Burk. Se encontró 27 que la adición de melaza con Ca2+ favorece el crecimiento del hongo sobre las otras fuentes de carbono no así la producción de proteína o la actividad enzimática. Además, se encontró que la producción de proteína fue 8 veces mayor (5684 ± 784 μg·mg-1) cuando se adicionó naringina con sales de Ca+2 y Mg+2. Por otra parte, la actividad enzimática fue 2 veces mayor cuando se adicionó ramnosa sin sales (2290 ± 157 U·mg-1). Finalmente, las características cinéticas determinadas fueron Vmax=13.24 U·mg-1 y Km=1.6 mM, con respecto a la actividad enzimática de la naringinasa comercial de P. decumbens (Vmax=3.96 U·mg-1 and Km=2.5 mM).

This paper presents the arrangement of a minimum set of components to track the vehicular dynamical behavior of a truck or an articulated vehicle, by using interpolated-GPS signals, vehicle CAN network, and MEMS inclinometers and accelerometers attached to a single on-board computer to evaluate vehicle maneuverability and performance.

Se presenta un arreglo con un mínimo de componentes para registro del comportamiento dinámico de un camión o semirremolque utilizando un interpolador de registros de GPS, la información del la Red CAN del vehículo e inclinómetros y acelerómetros MEMS conectados a una laptop con el propósito de evaluar la maniobrabilidad y confort del vehículo.