Study of antifungal agent caspofungin adsorption to laboratory materials.

Treatment of invasive fungal infections with Caspofungin is used as the first-line antifungal agents. The minimum inhibitory concentration value is a test which indicates the degree of sensitivity of a strain regarding a drug. However, no value of minimum inhibitory concentration for caspofungin is available because very variable value is obtained. In this work, we study the link with the adsorption phenomenon of CSF previously described in literature and the lack of minimum inhibitory concentration value. A systematic study of the impact of different parameters on CSF adsorption is reported. The effect of the nature of container material, the aqueous solution pH and the organic solvent proportion was studied. In addition, the possibility of using a coating agent to minimize the adsorption was assayed and evaluated. Results obtained showed the importance of the material used during the manipulation of CSF. The use of acidic pH aqueous solution or the addition of acetonitrile or methanol proportions (50 % and 70 %, respectively) were found efficient to avoid adsorption of CSF on glassware material, which is the relevant strategy for analytical samples of caspofungin. The treatment of HPLC glass vials and 96-well plates with N-(2-aminoethyl)-3-aminopropyltrimethoxysilane reduced the adsorption. The significant adsorption observed in this work especially with plastic materials, questions the results obtained before in different assays and explained the absence of MIC value.

Computational Simulation of Breast Tissue with Lesion Characterized by a Thermal Gradient Oriented to Anomalies Smaller than 1 cm of Diameter.

In this work, the computational simulation of thermal gradients related to internal lesions according to the phenomenon of pathological angiogenesis is proposed, this is based on the finite element method, and using a three¬dimensional geometric model adjusted to suit the real female anatomy. The simulation of the thermal distribution was based on the bioheating equation; it was carried out using the COMSOL Multiphysics® software. As a result, the simulation of both internal and superficial thermal distributions associated to lesions smaller than 1 cm and located inside the simulated breast tissue were obtained. An increase in temperature on the surface of the breast of 0.1 ° C was observed for a lesion of 5 mm in diameter and 15 mm in deep. A qualitative validation of the model was carried out by contrasting the simulation of anomalies of 10 mm in diameter at different depths (10, 15 and 20 mm) proposed in the literature, with the simulation of the model proposed here, obtaining the same behavior for the three cases.Clinical Relevance- The 3D computational tool adjusted to suit the anatomy of the real female breast allows obtaining the temperature distribution inside and on the surface of the tissue in healthy cases and with abnormalities associated with temperature elevations. It is an important characteristic of the model when the behavior of the parameters inside the tissue needs to be analyzed.

Melanin and pyomelanin in Aspergillus fumigatus: from its genetics to host interaction.

Aspergillus fumigatus is a worldwide-distributed saprophytic fungus and the major cause of invasive aspergillosis. This fungus can produce two types of melanin-dihydroxynaphthalene melanin (DHN-melanin) and pyomelanin. These pigments are considered important resistance mechanisms to stress, as well as virulence factors. The aim of this review is to present the current knowledge of the genetic basis and metabolic pathways of melanin production, their activation, function, and interaction with the host immune system. The DHN-melanin pathway is encoded in a cluster that includes six genes (abr1, abr2, ayg1, arp1, arp2, and pksP/alb1 genes) whose encoded proteins seem to be the origin of the pigment in endosomes. These vesicles are secreted and the pigment is subsequently located in the wall of the conidium beneath the rodlet layer. Unlike DHN-melanin, pyomelanin does not have its own biosynthetic pathway but is related to the activation of the L-tyrosine/L-phenylalanine degradation pathway that includes a cluster of six genes (hppD, hmgX, hmgA, fahA, maiA, and hmgR). Its production is due to the polymerization of homogentisic acid and is linked to conidial germination. Despite the knowledge gained in recent years, further studies will be necessary to confirm the pathways that produce these pigments and their role in the virulence mechanisms of A. fumigatus.

Prototipo de una Prótesis Mioeléctrica para la Emulación de una Articulación de Codo / Prototype of a Myoelectric Prosthesis for the Emulation of an Elbow Joint

En este trabajo se describe el desarrollo de un prototipo de prótesis mioeléctrica para la articulación de codo. Se dividió en tres partes, en la primera se describe el acondicionamiento de la señal mioeléctrica (SME) donde se propuso un circuito que está formado por una etapa de pre-amplificación, seguida de una etapa de filtrado, otra etapa de amplificación y por último la etapa de rectificación. Este circuito cumple con las especificaciones para la detección de la SME según el estado del arte. En la segunda parte se describe el procesamiento de la SME basado en el método TKEO, este se implementó en MatLAB (MathWorks- Natick, Massachusetts, USA) con la finalidad de detectar la actividad muscular, y resultó robusto y eficiente. La tercera parte se enfoca al diseño y construcción del prototipo, para el sistema de transmisión se usó un par de engranes y para el sistema de actuación los actuadores eléctricos; ambos se definieron según los criterios que se describen en este trabajo. Finalmente, se integraron las tres partes para la emulación de los movimientos flexión y extension del prototipo, haciendo uso del microprocesador (Arduino UNO) y del módulo de control de motores (Controlador de servo 1350 de Pololu).

In this paper the development of a prototype for a myoelectric prosthesis elbow joint is described. It is divided into three parts; the first is the conditioning of the myoelectric signal (SME) which proposed a circuit that is formed by a stage of pre-amplification, followed by a stage of filtering, another stage of amplification and finally a stage of rectification. This circuit complies with the specifications for the detection of the SME according to the state of the art. The second part is the processing of the SME based on the method TKEO, this was implemented in MatLAB (MathWorks - Natick, Massachusetts, USA) in order to detect if the muscle is active or not, and proved to be robust and efficient. The third part focuses on the design and realization of the prototype, in the system of transmission was used a couple of gears and for the system of actuation were electrical actuators; both were defined considering several criteria referred to in this work. Finally, the three parts were joined for the emulation of flexion and extension movements of the prototype, using the microprocessor (Arduino UNO) and control module (controller servo Pololu 1350).

Rapid and specific detection of section Fumigati and Aspergillus fumigatus in human samples using a new multiplex real-time PCR.

Invasive aspergillosis is an opportunistic infection caused primarily by Aspergillus fumigatus. However, other common fungal pathogens belonging to section Fumigati are often misidentified as A. fumigatus. Thus, we have developed a multiplex real-time PCR (qPCR) assay with primers and specific TaqMan probes based on internal transcribed spacer regions or benA gene to discriminate, in less than 3 h, species of section Fumigati and, specifically, A. fumigatus. The multiplex qPCR showed a limit of detection of 20 and 50 fg of DNA for section Fumigati and A. fumigatus, respectively. Moreover, it enabled detection of a single germinated conidia. The inclusion of some PCR facilitators together with the dilution of samples makes it possible to completely avoid PCR inhibitions in all bronchoalveolar lavage (BAL) samples assayed. This technique may be a useful complementary tool in the diagnosis of invasive pulmonary aspergillosis caused by A. fumigatus using BAL fluid.

Using 'stall detection' as an auxiliary mechanism for sensing obstacles and hand grasping in arm prosthesis.

This paper proposes a novel method for sensing obstacles and hand grasping activities in electromechanical arm prosthesis. The described method is based on indirectly sensing 'Stall' condition in prosthesis actuators through hall-effect sensors already embedded on its dc motors, thus not requiring external sensors. To test the proposed methodology, an electromechanical arm prosthesis of 3 degrees of freedom (DOF), plus 'open-close' of hand, which is being developed at CINVESTAV Mexico, was used. At the end of this paper, experimental measurements performed on the tested prosthesis, using and non using 'Stall Detection', are shown. We demonstrated that methodology can be used successfully for "sensing obstacles", but it cannot be used alone for "hand grasping". In any case, this technique demonstrated to be a good method to simplify and strengthen control of prosthesis.

[Efficacy and safety of fexofenadine and cetirizine in the treatment of allergic rhinitis]. / Eficacia y seguridad de la fexofenadina y la cetirizina en el tratamiento de la rinitis alérgica.

BACKGROUND: Allergic rhinitis affects 20 million of people in United States and a higher figure all around the world. OBJECTIVE: To evaluate the efficacy and safety of fexofenadine compared with certirizine in the treatment of allergic rhinitis. MATERIAL AND METHOD: It was carried out a prospective, double blind, comparative, randomized and multicentric study in patients with allergic rhinitis, with ages between 12 and 65 years. In the first phase, placebo was administered during three days to all the patients; and then, they were randomly allocated to receive fexofenadine 120 mg or cetirizine 10 mg in one dose a day during 14 days. Laboratory and cabinet tests at the beginning and at the end were performed to value security, as well as a global evaluation of the researcher to estimate effectiveness. RESULTS: 176 patients were included, 63.6% were women, average age was 27 years (+/- 12), 47.7% received fexofenadine and 52.2%, cetirizine. There was not significant difference in parameters of effectiveness nor of security in the studied group. CONCLUSION: The results of the present study confirm the efficacy and safety of the antihistaminic fexofenadine in the treatment of allergic rhinitis.

[Severe pre-eclampsia, HELLP syndrome and renal failure]. / Preeclampsia severa, síndrome HELLP e insuficiencia renal.

A retrospective study was done of thirty-patients with severe preeclampsia and HELLP syndrome whose developed acute renal failure, 25 patients also had acute tubular necrosis and five cases bilateral cortical necrosis with chronic renal insufficiency. Severe hypertension was present in all cases and anti-hypertensive therapy was needed. Six patients died, three due to intracranial hemorrhage, other two secondary to hypovolemic shock, and in one case multiple organ dysfunction.