Hongos filamentos de relave minero contaminado con plomo y zinc

The objective of the work was to identify genera of filamentous fungi and determine the concentration of lead and zinc in the mining tailings samples. We isolated and identified filamentous fungi using the serial dilution method and the micro culture technique respectively, we also determined heavy metals, pH and% H of tailings samples taken in three representative areas. We identified nine fungal genera: Penicillium, Aspergillus, Paecylomices, Acremonium, Chrysosporium, Trichoderma, Alternaria, Helicosporium and Geoctrichum from a total of sixty-two strains of filamentous fungi present in the mining tailings that had the following physical-chemical characteristics: Zinc (Zn) with 8810.4 ppm and lead (Pb) 3844.4 ppm, the pH had a variation of 1.75 - 7.85 and % H of 10.7 - 2.6.El objetivo del trabajo fue identificar géneros de hongos filamentosos y determinar la concentración de plomo y zinc en las muestras de relave minero. Aislamos e identificamos hongos filamentosos mediante el método de diluciones seriadas y la técnica de micro cultivo respectivamente, también determinamos metales pesados, pH y el % H de muestras de relave tomadas en tres áreas representativas. Identificamos nueve géneros fúngicos: Penicillium, Aspergillus, Paecylomices, Acremonium, Chrysosporium, Trichoderma, Alternaria, Helicosporium y Geoctrichum de un total de sesenta y dos cepas de hongos filamentosos presentes en el relave minero que presentaba las siguientes características físico químicas: Zinc (Zn) con 8810,4 ppm y plomo (Pb) 3844,4 ppm, el pH tuvo una variación de 1,75 – 7,85 y %H de 10,7 – 2,6

Hemispheric asymmetries in recognition memory for negative and neutral words

Journal of Eye Tracking, Visual Cognition and EmotionFedermeier and Benjamin (2005) have suggested that semantic encoding for verbal information in the right hemisphere can be more effective when memory demands are higher. However, other studies (Kanske & Kotz, 2007) also suggest that visual word recognition differ in function of emotional valence. In this context, the present study was designed to evaluate the effects of retention level upon recognition memory processes for negative and neutral words. Sample consisted of 15 right-handed undergraduate portuguese students with normal or corrected to normal vision. Portuguese concrete negative and neutral words were selected in accordance to known linguistic capabilities of the right hemisphere. The participants were submitted to a visual half-field word presentation using a continuous recognition memory paradigm. Eye movements were continuously monitored with a Tobii T60 eye-tracker that showed no significant differences in fixations to negative and neutral words. Reaction times in word recognition suggest an overall advantage of negative words in comparison to the neutral words. Further analysis showed faster responses for negative words than for neutral words when were recognised at longer retention intervals for left-hemisphere encoding. Electrophysiological data through event related potentials revealed larger P2 amplitude over centro-posterior electrode sites for words studied in the left hemifield suggesting a priming effect for right-hemisphere encoding. Overall data suggest different hemispheric memory strategies for the semantic encoding of negative and neutral words

Neuropsychological Performance in Patients with Asymptomatic HIV-1 Infection

Human immunodeficiency virus (HIV-1) infection and acquired immunodeficiency syndrome (AIDS) lead to neurocognitive disorders; however, there is still much knowledge to be gained regarding HIV-associated neurocognitive disorders. The purpose of this study was to assess the cognitive performance, instrumental activities of daily living, depression, and anxiety in patients with asymptomatic HIV-1 infections compared with seronegative participants without neurocognitive impairment. We studied a sample consisted of 60 patients with asymptomatic HIV-1 infections and 60 seronegative participants without neurocognitive impairment from the city of Barranquilla, Colombia, with a mean age of 36.07 years. A protocol of neuropsychological and psychopathological tests was applied to the participants. The group of patients with asymptomatic HIV infections significantly underperformed on tasks that assessed global cognitive screening, attention span, learning, phonemic verbal fluency, auditory-verbal comprehension, information processing speed, cognitive flexibility, and motor skills compared to the group of seronegative participants. No significant differences were found in memory, visual confrontation naming, vocabulary, inhibition, and instrumental activities of daily living. Additionally, the patients with asymptomatic HIV-1 infection had a higher anxiety index than the seronegative participants, but no significant difference was found in depression. A correlation was found between depression and anxiety. In conclusion, the patients with asymptomatic HIV-1 infection had lower cognitive performances than the seronegative participants in the cognitive functions mentioned above and more anxiety but still performed the instrumental activities of daily living

Evaluación del complejo enzimático celulasa en hongos nativos del Perú

In Peru, information on the biotechnological potential of native fungi for the degradation of cellulose presents few records. This work aimed to evaluate the cellulolytic activity of isolated fungi in the departments of Cajamarca, Lima, Junín and Huánuco. 289 species of fungi were subjected to reactivation after a conservation period of 7 years using filter paper and Czapeck broth, evaluated semi-quantitatively using the radial diffusion technique on Czapeck Na-CMC agar to then select five strains that were morphologically identified and its cellulolytic capacity was also determined by the Somogyi-Nelson method. 90% (260) of the fungi that underwent semi-quantitative evaluation were reactivated, selecting five strains for their greater clearance area: 14.9, 12.5, 12.0, 14.4 and 12.7 x 102 mm2; SA 726 (Paecilomyces sp), SA 668 (Paecilomyces sp), SA 651 (Paecilomyces sp), SA 683 (Fusarium sp) and HN 566 (Aspergillus sp) with EA of: 0.048, 0.042, 0.042, 0.080 and 0.048 IU / ml respectively. The native strains evaluated maintain good viability over time and retain the ability to degrade cellulose. These strains can be used in biotechnological processes for the treatment of agroindustrial effluents.En el Perú información sobre el potencial biotecnológico de los hongos nativos para la degradación de la celulosa presenta escasos registros. Este trabajo tuvo como objetivo evaluar la actividad celulolítica de hongos aislados en los departamentos de Cajamarca, Lima, Junín y Huánuco. 289 especies de hongos fueron sometidos a reactivación después de un periodo de conservación de 7 años empleando papel filtro y caldo Czapeck, evaluados de manera semicuantitativa empleando la técnica de difusión radial en agar Czapeck Na-CMC para luego seleccionar cinco cepas que fueron identificadas morfológicamente y también se determinó su capacidad celulolítica por el método de Somogyi-Nelson. Se reactivaron 90% (260) de los hongos que pasaron por evaluación semicuantitativa, seleccionando cinco cepas por su mayor área de aclaramiento: 14.9, 12.5, 12.0, 14.4 y 12.7 x 102 mm2; SA 726 (Paecilomyces sp), SA 668 (Paecilomyces sp), SA 651 (Paecilomyces sp), SA 683 (Fusarium sp) y HN 566 (Aspergillus sp) con AE de: 0.048, 0.042, 0.042, 0.080 y 0.048 UI/ml respectivamente. Las cepas nativas evaluadas mantienen una buena viabilidad en el tiempo y conservan la capacidad para degradar celulosa. Estas cepas pueden ser empleadas en procesos biotecnológicos para el tratamiento de efluentes agroindustriales