Hyperspectral Face Recognition with Adaptive and Parallel SVMs in Partially Hidden Face Scenarios.

Hyperspectral imaging opens up new opportunities for masked face recognition via discrimination of the spectral information obtained by hyperspectral sensors. In this work, we present a novel algorithm to extract facial spectral-features from different regions of interests by performing computer vision techniques over the hyperspectral images, particularly Histogram of Oriented Gradients. We have applied this algorithm over the UWA-HSFD dataset to extract the facial spectral-features and then a set of parallel Support Vector Machines with custom kernels, based on the cosine similarity and Euclidean distance, have been trained on fly to classify unknown subjects/faces according to the distance of the visible facial spectral-features, i.e., the regions that are not concealed by a face mask or scarf. The results draw up an optimal trade-off between recognition accuracy and compression ratio in accordance with the facial regions that are not occluded.

Estudio comparativo morfológico y morfométrico para la determinación de sexo en mandíbulas humanas / Comparative morphological and morphometric study for sex determination in human mandibles

Introducción: En la especie humana, las diferencias obedecen a variaciones biológicas ligadas a los caracteres sexuales, conducta socio-cultural y epigenética en cada grupo poblacional. Estas variaciones biológicas entre sexos se analizan desde el punto de vista morfológico. Algunos estudios refieren que la morfometría, relacionando el tamaño y forma del esqueleto humano, conduce a resultados más fidedignos y reproducibles. Objetivo: comparar los caracteres morfológicos y morfométricos de los detalles anatómicos propios de la rama mandibular para determinar el sexo en mandíbulas humanas, en dos poblaciones venezolanas. Materiales e métodos: la muestra fue 16 mandíbulas encontradas como hallazgo fortuito en el 2004 (Población A) y 08 mandíbulas humanas procedentes de la Colección de paleodemográfica, constituida por restos óseos de la población del yacimiento del Valle de Quíbor (Edo. Lara) (Población B). Posteriormente, fueron analizadas morfológico y métricamente, empleando los puntos de referencia anatómicos o PAR/Lamarck, y valoradas en el paquete estadístico SSPS (versión 19). Resultados: la rama mandibular es una muestra confiable para la discriminación sexual, después del análisis morfológico y métrico, de los 16 individuos procedentes de la población A, 07 corresponden con los criterios femeninos y 09 a masculinos. En la muestra de 08 individuos procedente de la población B, se identificaron 03 individuos femeninos y 05 masculinos. Conclusiones: el uso de métodos morfológico e morfométrico siguen siendo necesarios como primer paso para el reconocimiento de individuos en las ciencias forenses. No obstante, fue más efectivo la discriminación sexual mediante los parámetros morfométricos en relación al método morfológico.

Evaluación del desempeño pronóstico de dos puntajes de predicción de mortalidad a siete días en pacientes adultos oncológicos críticamente enfermos admitidos en una unidad de cuidados intensivos / Prognostic performance assessment of two seven-day mortality prediction scores in oncologic critically ill adult patients admitted to an intensive care unit

Resumen Introducción: los sistemas de puntuación para predicción se han desarrollado para medir la severidad de la enfermedad y el pronóstico de los pacientes en la unidad de cuidados intensivos. Son útiles para la toma de decisiones clínicas, la estandarización de la investigación y la comparación de la calidad de la atención. Material y métodos: estudio observacional analítico de cohorte en el que revisaron las historias clínicas de 283 pacientes oncológicos admitidos en la unidad de cuidados intensivos (UCI) del Centro de Investigaciones Oncológicas CIOSAD, durante enero de 2014 a enero de 2016, a quienes se les estimó la probabilidad de mortalidad con los puntajes pronósticos APACHE IV y MPM II, se realizó regresión logística binaria con las variables de los modelos en sus estudios originales, se determinó calibración, discriminación y se calcularon criterios de información Akaike AIC y Bayesiano BIC. Resultados: en la evaluación de desempeño de los puntajes pronósticos APACHE IV mostró mayor capacidad de predicción (AUC = 0.95) versus MPM II (AUC = 0.78), los dos modelos mostraron adecuada calibración con estadístico de Hosmer y Lemeshow para APACHE IV (p = 0.39) y para MPM II (p = 0.99). El delta BIC es 2.9 mostrando evidencia positiva en contra de APACHE IV. El estadístico AIC es menor para APACHE IV indicando que es el puntaje con mejor ajuste a los datos. Conclusiones: APACHE IV tiene un buen desempeño en la predicción de mortalidad de pacientes oncológicos críticamente enfermos. Es una herramienta útil para el clínico en su labor diaria. al permitirle distinguir los pacientes con alta probabilidad de mortalidad. (Acta Med Colomb 2018; 43: 81-89).

Abstract Introduction: scoring systems for prediction have been developed to measure the severity of the disease and the prognosis of patients in the intensive care unit. They are useful for clinical decision-making, standardizing research and comparing the quality of care. Materials and Methods: an observational cohort analytical study in which the medical records of 283 oncological patients admitted to the intensive care unit (ICU) of the CIOSAD Oncology Research Center from January 2014 to January 2016 were reviewed. The probability of mortality with the APACHE IV and MPM II prognostic scores was estimated, binary logistic regression was performed with the variables of the models in their original studies, calibration, discrimination was determined and Akaike AIC and Bayesian BIC information criteria were calculated. Results: in the evaluation of the performance of the prediction scores, APACHE IV showed greater predictive capacity (AUC = 0.95) versus MPM II (AUC = 0.78); the two models showed adequate calibration with Hosmer and Lemeshow statistics for APACHE IV (p = 0.39) and for MPM II (p = 0.99). The BIC delta is 2.9 showing positive evidence against APACHE IV. The AIC statistic is lower for APACHE IV indicating that it is the score with the best fit to the data. Conclusions: APACHE IV has a good performance in the prediction of mortality of critically ill oncologic patients. It is a useful tool for the clinician in his daily work, allowing him to distinguish patients with a high probability of mortality. (Acta Med Colomb 2018; 43: 81-89).

Overexpression of MMP-3 and uPA with Diminished PAI-1 Related to Metastasis in Ductal Breast Cancer Patients Attending a Public Hospital in Mexico City.

Extracellular matrix metalloproteases and the fibrinolytic system are important protease systems interacting with each other in charge of remodeling and recycling of tissues. Their role in tumor invasion and metastasis is often discussed. In this study several metalloproteases such as MMP-1, MMP-3, MMP-9, and TIMP-1 together with molecules from the fibrinolytic system like uPA, its receptor uPAR, and its inhibitor, PAI-1, were studied by immune-histochemistry to establish a comparison with and without metastasis. From the (118) primary tumors of Mexican patients with ductal breast cancer studied, 56% were grade II and 69% were size T2; the group with metastatic ganglia included 64 samples (54.3%). In patients with metastasis the estimated expression of MMP-3 and uPA (resp., 28% and 45%) was higher than that from no metastatic tumors; it means there is higher expression of both markers in metastatic tumors (p < 0.05). At the same time, metastatic tumors showed statistically significant lower signal of PAI-1 (24%) than tumors without metastasis (p < 0.05). We concluded that overexpression of MMP-3 and uPA, altogether with diminished expression of PAI-1 from metastatic tumors, might be a crucial step towards metastasis in ductal breast cancer. Nevertheless, additional studies in different populations are necessary to establish a pattern.

Variability of Serum Thyroglobulin Levels in Post- Thyroidectomy Patients with Well-Differentiated Thyroid Cancer: the ATA Guidelines.

OBJECTIVE: Evaluate the variability of stimulated serum thyroglobulin (Tg) levels in post-thyroidectomy patients with well-differentiated thyroid cancer (WDTC) and determine the frequency of undetectable Tg in patients with evidence of functional thyroid tissue after a 131-I whole-body scan (WBS). METHODS: A retrospective record review of patients with WDTC referred to our clinic from 1990 to 2010. Demographic data, histology, staging, imaging studies, stimulated Tg values, and the presence if applicable of Tg antibodies (TgAb) were documented. The images of whole-body radioiodine scans were reviewed to assess the extent of functional thyroid tissue. RESULTS: A total of 142 cases were evaluated with 417 studies. There were 112 women and 30 men; the median age was 47 years. The tumor histologies included 97 papillary (4 had the Hurthle cell variant), 33 papillary-follicular tumor, and 12 follicular tumors; 7 were multifocal. ATA classification was used; groups were divided into low (55%) and intermediate-high risk (45%). The final analysis comprised 84 patients, having among them 170 studies that included Tg values in their records. The cut-off value for Tg was 2.0 ng/ml, and for TgAb, it was 20 IU/ml or more. Residual functional tissue was present in 105 (62%) cases. Discordant Tg results were found in 55% of the low-risk patients; of those, only 3 had TgAb. In the intermediate- and high-risk group, 47% had discordant results; 2 cases had TgAb. CONCLUSION: The variability of the Tg levels and the high frequency of discordant results (positive WBSs with undectable Tg levels) bring into question the standard recommendation of conservative management for low-risk patients. Follow-ups should include a Tg assay and imaging studies.

MEDICIÓN INDIRECTA DE LA TASA DE CONSUMO DE ADULTOS E INMADUROS DE Trialeurodes vaporariorum (HEMIPTERA: ALEYRODIDAE) SOBRE FRÍJOL / Indirect Measurement of the Rate of Consumption of Adult and Immature of Trialeurodes vaporariorum (Hemiptera: Aleyrodidae) On Common Bean

La biología y ecología de la mosca blanca de los invernaderos, Trialeurodes vaporariorum (Westwood) (Hemiptera: Aleyroridae), se encuentra ampliamente documentada. Sin embargo, hasta el momento no hay reportes acerca de la tasa de consumo de alimento por este fitófago, un parámetro necesario para modelos de simulación. Por tal motivo, el objetivo de esta investigación fue la medición indirecta del consumo de alimento por el adulto e instares inmaduros de T. vaporariorum basado en metodologías encontradas en la literatura científica. La estimación de la tasa de consumo de alimento por adultos se realizó bajo condiciones de laboratorio, utilizando como unidad experimental una planta de fríjol de dos semanas de edad. El experimento consistió de dos tratamientos: (T1) plantas libres de cualquier fitófago y (T2) plantas sometidas a infestaciones con T. vaporariorum, cada tratamiento con 20 repeticiones y una réplica en el tiempo de todo el experimento. Se registró el peso fresco diariamente en ambos tratamientos. Para el caso de los inmaduros, la unidad experimental consistió en una hoja cotiledónea de fríjol, infestada con una población determinada de inmaduros de cada instar de mosca blanca teniendo así cinco tratamientos (Instar I, II, III, IV y Control) cada uno con 17 repeticiones. Se registró diariamente el peso fresco de las hojas. Se obtuvo un consumo promedio de alimento por el adulto de 0,277 ± 0,0042 mg.dia-1. Para los dos primeros instares ninfales se estimó una tasa de consumo de 0,052 mg.dia-1, en el tercer instar de 0,14 mg.dia-1, y para el cuarto instar de 0,19 mg.dia-1. Un adulto de mosca blanca puede consumir en un día seis veces su peso y un inmaduro ocho veces, gracias a su rápido metabolismo y la constante excreción de mielecilla.

The biology and ecology of the greenhouse whitefly, Trialeurodes vaporariorum Westwood (Hemiptera: Aleyroridae), is widely documented. However, so far there are not reports about the rate of consumption of this phytophagous. Therefore, the objective of this research was to measure the food consumption by the adult and immature instars of T. vaporariorum based on indirect methodologies found in the literature. The estimate of the food consumption rate by adults was conducted under laboratory conditions, using as experimental units plant beans two weeks old. The experiment consisted of two treatments: (T1) plants free from any phytophagous and (T2) plants subjected to infestation with T. vaporariorum, with 20 repetitions each treatment and replicated over time. In the case of the immature individuals, the experimental unit consisted of a bean cotyledon leaf infested with a population of immature individuals of each instar of whitefly, having five treatments (Instar I, II, III, IV and Control) each with 17 repetitions. Fresh weight of leaves was recorded daily. An average food consumption of 0.277 ± 0.0042 mg.day-1 was obtained for the adult. For the first two nymphal instars food consumption rate of 0.052 mg.day-1 was estimated, for the third instar 0.14 mg.day-1, and for the fourth instar 0.19 mg.day-1. An whitefly adult can consume in a day six times its weight and an immature eight times, this thanks to the rapid metabolism and a constant excretion of honeydew of the species.

Integrating reconfigurable hardware-based grid for high performance computing.

FPGAs have shown several characteristics that make them very attractive for high performance computing (HPC). The impressive speed-up factors that they are able to achieve, the reduced power consumption, and the easiness and flexibility of the design process with fast iterations between consecutive versions are examples of benefits obtained with their use. However, there are still some difficulties when using reconfigurable platforms as accelerator that need to be addressed: the need of an in-depth application study to identify potential acceleration, the lack of tools for the deployment of computational problems in distributed hardware platforms, and the low portability of components, among others. This work proposes a complete grid infrastructure for distributed high performance computing based on dynamically reconfigurable FPGAs. Besides, a set of services designed to facilitate the application deployment is described. An example application and a comparison with other hardware and software implementations are shown. Experimental results show that the proposed architecture offers encouraging advantages for deployment of high performance distributed applications simplifying development process.

New structural features of Acacia tortuosa gum exudate.

Acacia tortuosa produces a clear gum, very soluble in water. Previous reports showed that it was constituted by four fractions, one of them an arabinogalactan-protein complex. The elucidation of the A. tortuosa gum structure by the combination of classical chemical methods, size exclusion chromatography and NMR spectroscopy, was the objective of this investigation. The data obtained show that the heteropolysaccharide is an arabinogalactan type II, highly ramified, with lateral chains at C-2 as well as at C-6 of the galactose 3-O residues; mono-O-substituted galactoses were not detected. There are residues of mannose, the arabinose, pyranose predominantly, is terminal and 2-O-linked. The abundance of the 4-O-methyl-α-d-glucuronic acid was not previously reported. The proteic fraction is probably represented by an arabinogalactan-protein complex that binds poorly with ß-glucosyl Yariv reagent, and two glycoproteins. The NMR spectra suggest that the carbohydrate links to hydroxyproline through the galactose (galactosylation).

Real-time algebraic derivative estimations using a novel low-cost architecture based on reconfigurable logic.

Time derivative estimation of signals plays a very important role in several fields, such as signal processing and control engineering, just to name a few of them. For that purpose, a non-asymptotic algebraic procedure for the approximate estimation of the system states is used in this work. The method is based on results from differential algebra and furnishes some general formulae for the time derivatives of a measurable signal in which two algebraic derivative estimators run simultaneously, but in an overlapping fashion. The algebraic derivative algorithm presented in this paper is computed online and in real-time, offering high robustness properties with regard to corrupting noises, versatility and ease of implementation. Besides, in this work, we introduce a novel architecture to accelerate this algebraic derivative estimator using reconfigurable logic. The core of the algorithm is implemented in an FPGA, improving the speed of the system and achieving real-time performance. Finally, this work proposes a low-cost platform for the integration of hardware in the loop in MATLAB.

Facilitating preemptive hardware system design using partial reconfiguration techniques.

In FPGA-based control system design, partial reconfiguration is especially well suited to implement preemptive systems. In real-time systems, the deadline for critical task can compel the preemption of noncritical one. Besides, an asynchronous event can demand immediate attention and, then, force launching a reconfiguration process for high-priority task implementation. If the asynchronous event is previously scheduled, an explicit activation of the reconfiguration process is performed. If the event cannot be previously programmed, such as in dynamically scheduled systems, an implicit activation to the reconfiguration process is demanded. This paper provides a hardware-based approach to explicit and implicit activation of the partial reconfiguration process in dynamically reconfigurable SoCs and includes all the necessary tasks to cope with this issue. Furthermore, the reconfiguration service introduced in this work allows remote invocation of the reconfiguration process and then the remote integration of off-chip components. A model that offers component location transparency is also presented to enhance and facilitate system integration.

A reasoning hardware platform for real-time common-sense inference.

Enabling Ambient Intelligence systems to understand the activities that are taking place in a supervised context is a rather complicated task. Moreover, this task cannot be successfully addressed while overlooking the mechanisms (common-sense knowledge and reasoning) that entitle us, as humans beings, to successfully undertake it. This work is based on the premise that Ambient Intelligence systems will be able to understand and react to context events if common-sense capabilities are embodied in them. However, there are some difficulties that need to be resolved before common-sense capabilities can be fully deployed to Ambient Intelligence. This work presents a hardware accelerated implementation of a common-sense knowledge-base system intended to improve response time and efficiency.

Pathogenicity island cag, vacA and IS605 genotypes in Mexican strains of Helicobacter pylori associated with peptic ulcers.

BACKGROUND: Helicobacter pylori is associated with chronic gastritis, peptic ulcers, and gastric cancer. Two major virulence factors of H. pylori have been described: the pathogenicity island cag (cag PAI) and the vacuolating cytotoxin gene (vacA). Virtually all strains have a copy of vacA, but its genotype varies. The cag PAI is a region of 32 genes in which the insertion of IS605 elements in its middle region has been associated with partial or total deletions of it that have generated strains with varying virulence. Accordingly, the aim of this work was to determine the cag PAI integrity, vacA genotype and IS605 status in groups of isolates from Mexican patients with non-peptic ulcers (NPU), non-bleeding peptic ulcers (NBPU), and bleeding peptic ulcers (BPU). METHODS: The cag PAI integrity was performed by detection of eleven targeted genes along this locus using dot blot hybridization and PCR assays. The vacA allelic, cag PAI genotype 1 and IS605 status were determined by PCR analysis. RESULTS: Groups of 16-17 isolates (n = 50) from two patients with NPU, NBPU, and BPU, respectively, were studied. 90% (45/50) of the isolates harbored a complete cag PAI. Three BPU isolates lacked the cag PAI, and two of the NBPU had an incomplete cag PAI: the first isolate was negative for three of its genes, including deletion of the cagA gene, whereas the second did not have the cagM gene. Most of the strains (76%) had the vacA s1b/m1 genotype; meanwhile the IS605 was not present within the cag PAI of any strain but was detected elsewhere in the genome of 8% (4/50). CONCLUSION: The patients had highly virulent strains since the most of them possessed a complete cag PAI and had a vacA s1b/m1 genotype. All the isolates presented the cag PAI without any IS605 insertion (genotype 1). Combined vacA genotypes showed that 1 NPU, 2 NBPU, and 1 BPU patients (66.6%) had a mixed infection; coexistence of H. pylori strains with different cag PAI status was observed in 1 NBPU and 2 BPU (50%) of the patients, but only two of these patients (NBPU and BPU) had different vacA genotypes.

Culture supernatants from V. cholerae O1 ElTor strains isolated from different geographic areas induce cell vacuolation and cytotoxicity / Cepas de V. cholerae O1 biotipo ElTor aisladas de diferente origen geográfico inducen vacuolización celular y citotoxicidad

OBJECTIVE: To investigate whether the HlyA-induced vacuolating effect is produced by V. cholerae O1 ElTor strains isolated from different geographic origins, including Mexico. MATERIAL AND METHODS: Supernatant-induced haemolysis, vacuolating activity and cytotoxicity in Vero cells were recorded. PCR, RFLP analysis and molecular cloning were performed. RESULTS: All ElTor strains analyzed induced cellular vacuolation. Ribotype 2 strains isolates from the U.S. gulf coast yielded the highest titer of vacuolating activity. Eight of nine strains were haemolytic, while all strains were PCR positive for the hlyA gene. We cloned the hlyA gene from two ElTor strains, a toxigenic (2514-88, ctxAB+) and a non-toxigenic Mexican strain (CM 91-3, ctxAB-). Supernatant from those recombinant E. coli strains induced haemolysis, cell vacuolation and cytotoxicity. RFLP-PCR analysis revealed similarities in the hlyA gene from all strains tested. CONCLUSION: The HlyA-induced vacuolating effect is a widespread phenotype of epidemic V. cholerae O1 ElTor strains.

OBJETIVO: Analizar el efecto vacuolizante de cepas de V. cholerae O1 ElTor aisladas de diferente origen geográfico, incluyendo México. MATERIAL Y MÉTODOS: Se realizaron pruebas de hemolisis, vacuolización y citotoxicidad en células Vero, así como PCR, análisis por RFLP y clonación molecular. RESULTADOS: Todas las cepas indujeron el efecto vacuolizante. Las cepas del ribotipo 2, aisladas de las costas del Golfo en Estados Unidos, presentaron títulos altos de vacuolización. El gen hlyA fue amplificado en las nueve cepas mediante PCR, aunque sólo ocho fueron hemolíticas. Se clonó el gen hlyA de una cepa toxigénica (2514-88, ctxAB+) y de una cepa no toxigénica aislada en México (CM 91-3, ctxAB-). El sobrenadante de las clonas recombinantes indujo hemólisis, efecto vacuolizante y citotoxicidad. El RFLP mostró alta similitud del gen hlyA de las cepas estudiadas. CONCLUSIÓN: El efecto vacuolizante es un fenotipo ampliamente distribuido en cepas epidémicas de V. cholerae O1 biotipo ElTor.

Culture supernatants from V. cholerae O1 El Tor strains isolated from different geographic areas induce cell vacuolation and cytotoxicity.

OBJECTIVE: To investigate whether the HlyA-induced vacuolating effect is produced by V. cholerae O1 ElTor strains isolated from different geographic origins, including Mexico. MATERIAL AND METHODS: Supernatant-induced haemolysis, vacuolating activity and cytotoxicity in Vero cells were recorded. PCR, RFLP analysis and molecular cloning were performed. RESULTS: All ElTor strains analyzed induced cellular vacuolation. Ribotype 2 strains isolates from the U.S. gulf coast yielded the highest titer of vacuolating activity. Eight of nine strains were haemolytic, while all strains were PCR positive for the hlyA gene. We cloned the hlyA gene from two ElTor strains, a toxigenic (2514-88, ctxAB+) and a non-toxigenic Mexican strain (CM 91-3, ctxAB-). Supernatant from those recombinant E. coli strains induced haemolysis, cell vacuolation and cytotoxicity. RFLP-PCR analysis revealed similarities in the hlyA gene from all strains tested. CONCLUSION: The HlyA-induced vacuolating effect is a widespread phenotype of epidemic V. cholerae O1 ElTor strains.

Re-organization of mitochondria at the NK cell immune synapse.

As part of the innate immune response NK cells destroy infected, transformed, or otherwise stressed cells within hours of activation. In contrast, CD4(+) T lymphocytes require a sustained increase in their metabolism in order to cope with the biogenesis of cell components, in a process of proliferation and differentiation into effector cells. Recently, mitochondria have been implied in T lymphocyte immune synapse function but little is known on the role of mitochondria in the NK cell interaction with tumour cells. Here we analysed NK cells mitochondrial membrane potential (Deltapsi(m)) as an indicator of mitochondrial energy status and cellular homeostasis. Upon contact with K562 tumour cells, NK cells undergo Deltapsi(m) depolarization, indicating a rapid consumption of their metabolic energy. Furthermore, pharmacological inhibition of ATP synthesis down-regulates NK cell cytotoxic activity. Confocal- and electron-microscopy analyses showed re-organization of NK cells mitochondria towards the site of interaction with K562 tumour cell (NK cell immune synapse), perhaps as a way to compensate for local energy consumption. Interestingly, mitochondrial re-organization also takes place following NK stimulation with anti-NKGD2 antibodies but not with anti-KIR2DL1 antibodies, suggesting that activating rather than inhibiting cell signalling, triggered by NK cell receptors, is involved in NK cell mitochondria dynamics.

Funcionalidad de una mezcla de gomas de acasia glomerosa, Enterolobium cyclocarpum e Hymenaea courbaril en la preparación de helados de bajo contenido calórico / Functionality of a mixture of gums from acacia glomerosa, Enterolobium cyclocarpum and Hymenea courbaril in the low fat ice-cream preparation

Acacia glomerosa, Anterolobium cyclocarpum e Hymenaea courbaril, especies arbóreas ampliamente disemindas en Venezuela producen gomas con buen rendimiento. La mezcla de estas gomas se ensayó, como estabilizante en la preparación de helados de bajo contenido calórico. La viscosidad, el porcentaje de derretido y las propiedades sensoriales fueron determinados. Estas características físico-químicas se compararon con las exhibidas por los productos obtenidos con base en mezcla de gomas comerciales. La mezcla de gomas de las especies estudiadas incrementó la viscocidad del sistema, por lo tanto, favoreció una excelente incorporación y una distribución uniforme del aire; aportó textura y estabilidad durante el almacenamiento; mejoró la capacidad de expansión de la espuma y las propiedades de derretido. Por otra parte, aportó buenas características sensoriales, como la indica el alto puntaje alcanzado; apariencia (7.78), cremosidad (7.62), sabor (8.01) y bajo puntaje en presencia de cristales de hielo (3.06). Este trabajo evidenció la funcionalidad como estabilizante de la mezcla de gomas investigadas en la preparación de helados bajo en calorías.

Acacia glomerosa, Enterolobium cyclocarpum and Hymenaea courbaril, species widely disseminated in Venezuela, South America, produce gum with good yield. The mixture of these gums was tested as stabilizer in the low fat ice cream preparation. Viscosity, overrun, foam expansion, meltdown, shape factor and sensory properties were determined. These quality characteristics were compared with those exhibited by the product obtained with a mixture of commercial gums. The mixture tested provided the suitable viscosity for the ice cream mix with the corresponding overrun and texture. It gave better foaming properties and air incorporation. On the other hand, it was demonstrated the good sensory attributes by the highest score i.e. appearance (7.78), creaminess (7.62), flavor (8.01) and lowest score of iciness (3.06). This work showed good functionality as stabilizer of the mixture of gums investigated in the low fat ice cream preparation.

Funcionalidad de la goma de enterolobium cyclocarpum en la preparación de yogurt líquido semi-descremado / Funtionality of enterolobium cyclocarpum gum in the preparation of liquid low fat yogurt

Enterolobium cyclocarpum (Mimosaceae), especie localizada en Venezuela, produce goma con excelentes características físicio-químicas y alto rendimiento. Se evaluó la funcionalidad de esta goma como aditivo en la preparación de yogurt líquido semi-descremado. Cinco tratamientos fueron aplicados, control (sin goma) y otros a diferentes concentraciones de goma (0,05; 0,10; 0,15; 0,20 por ciento). Las características físico-químicas del producto (grasa, sólidos no grasos, acidez láctica, pH, viscosidad, sinéresis) y las propiedades sensoriales fueron investigadas. Se aplicó un análisis estadístico (ANOVA). El producto, obtenido con la mayor concentración de goma (0,20 por ciento) difiere estadísticamente (P<0,05) de aquellos obtenidos a las menores concentraciones de goma y del tratamiento control (sin goma). La goma ensayada (0,20 por ciento) proporcionó la viscosidad adecuada al yogurt, con bajo fenómeno de sinéresis y buena textura. Además, el producto exhibió los mejores atributos sensoriales, como lo indica el alto puntaje alcanzado: apariencia (6,98), sabor (7,12) textura (7,18) y aceptación (7,48). Estos resultados muestran una buena funcionalidad de la goma de E.cyclocarpum en la preparación de yogurt líquido semi-descremado

The use of and ELISPOT assay to evaluate intestinal and systemic antibody responses to locally administered Entamoeba histolytica antigen in mice

The local induction of humoral immune response to Entamoeba histolytica trophozoites in the gut has not been studied. This work reports some of our recent studied. This work reports some of our recent studies aimed to induce optimal immune responses against E. histolytica in mice and to describe a novel approach for monitoring mucosal immune responses induced in the gastrointestinal tract and expressed locally and systemically. We have compared the kinetics of both mucosal and systemic primary antibody responses to E. histolytica in the Peyer's patches (PP) and the spleen in Balb/c mice after a single dose of glutaraldehyde fixed amebas (GFA) by intragastric (IG), rectal (R), and intraperitoneal (IP) routes. The number of antibody-secreting cells directed to E. histolytica was assessed by the technique of ELISPOT on mitrocellulose filters. The antibody response to E. histolytica was detected in both PP and spleen with the three routes, indicating that either mucosal or systemic stimulation by GFA generates both types of response. We also determined the total antibody response in entestinal fluids and the antibody secretions from spleen and PP cells in vitro and found differences between male and female mice