The Role of CyaY in Iron Sulfur Cluster Assembly on the E. coli IscU Scaffold Protein

Progress in understanding the mechanism underlying the enzymatic formation of iron-sulfur clusters is difficult since it involves a complex reaction and a multi-component system. By exploiting different spectroscopies, we characterize the effect on the enzymatic kinetics of cluster formation of CyaY, the bacterial ortholog of frataxin, on cluster formation on the scaffold protein IscU. Frataxin/CyaY is a highly conserved protein implicated in an incurable ataxia in humans. Previous studies had suggested a role of CyaY as an inhibitor of iron sulfur cluster formation. Similar studies on the eukaryotic proteins have however suggested for frataxin a role as an activator. Our studies independently confirm that CyaY slows down the reaction and shed new light onto the mechanism by which CyaY works. We observe that the presence of CyaY does not alter the relative ratio between [2Fe2S]2+ and [4Fe4S]2+ but directly affects enzymatic activity

Inter-Rater Variability in the Evaluation of Lung Ultrasound in Videos Acquired from COVID-19 Patients

12 páginas, 7 figuras, 1 tablaLung ultrasound (LUS) allows for the detection of a series of manifestations of COVID-19, such as B-lines and consolidations. The objective of this work was to study the inter-rater reliability (IRR) when detecting signs associated with COVID-19 in the LUS, as well as the performance of the test in a longitudinal or transverse orientation. Thirty-three physicians with advanced experience in LUS independently evaluated ultrasound videos previously acquired using the ULTRACOV system on 20 patients with confirmed COVID-19. For each patient, 24 videos of 3 s were acquired (using 12 positions with the probe in longitudinal and transverse orientations). The physicians had no information about the patients or other previous evaluations. The score assigned to each acquisition followed the convention applied in previous studies. A substantial IRR was found in the cases of normal LUS (κ = 0.74), with only a fair IRR for the presence of individual B-lines (κ = 0.36) and for confluent B-lines occupying 50% (κ = 0.50). No statistically significant differences between the longitudinal and transverse scans were found. The IRR for LUS of COVID-19 patients may benefit from more standardized clinical protocols.This research was partially funded by CDTI (Spanish acronym: Centre for Industrial Tech- nological Development), funding number COI-20201153. Partially supported by the Google Cloud Research Credits program with the funding number GCP19980904, by the project RTI2018-099118- A-I00 founded by MCIU/AEI/FEDER UE and by the European Commission–NextGenerationEU, through CSIC’s Global Health Platform (PTI Salud Global)

Investigación - Acción: reseña y aportes del taller de creatividad del consultorio psicológico de la Universidad Nacional Mayor de San Marcos

Se realiza una primera evaluación del Taller de Creatividad del Consultorio Psicológico de la UNMSM, destacando las fortalezas presentes y las potencialidades futuras de la práctica de formación en creatividad personal, considerando sus aportes al desarrollo institucional y a la comunidad

Investigación-acción: reseña y aportes del taller de creatividad del Consultorio Psicológico de la Universidad Nacional Mayor de San Marcos

It carries out a first evaluation of the Creativity Workshop of the Psychological office of the UNMSM, highlighting the present fortresses and the future potentialities of training in personal creativity practice, considering its contributions to the institutional development and to the community.Se realiza una primera evaluación del Taller de Creatividad del Consultorio Psicológico de la UNMSM, destacando las fortalezas presentes y las potencialidades futuras de la práctica de formación en creatividad personal, considerando sus aportes al desarrollo institucional y a la comunidad

Relaciones tróficas entre el calamar gigante DosidDicus gigas y el pez luminoso Vinciguerria lucetia en el sistema de la corriente de Humboldt de Perú

9 pages, 4 figures, 3 tables[EN] Acoustic surveys for assessing the biomass and distribution of the jumbo squid (Dosidicus gigas) and the lightfish (Vinciguerria lucetia) were carried out in the Humboldt Current System of Peru in 2007 and 2008. At the same time, 937 jumbo squid were caught and their stomach contents analyzed. The diet of the jumbo squid was dominated by mesopelagic fish. The first component of their fish diet was V. lucetia and the second component was the myctophid fish Diogenichthys laternatus. Acoustic biomass estimates of these species show that V. lucetia is an important component in aggregative structures in the Humboldt Current System of Peru and its distribution and movements are closely related to the migratory movements of the jumbo squid. The trophic relationship observed between D. gigas and V. lucetia promotes an increase in jumbo squid biomass and, has a positive trophic effect on the ocean ecosystem[ES] La biomasa de calamar gigante Dosidicus gigas y el pez mesopelágico Vinciguerria lucetia se obtuvo a partir de detección acústica en la Corriente de Humboldt de Perú durante 2007 y 2008. Simultáneamente, 937 calamares fueron capturados y se les analizó el contenido estomacal. La dieta de D. gigas estuvo dominada por peces, siendo V. lucetia el principal componente y en segundo lugar el mictófido Diogenichthys laturnatus. A partir de la evaluación de la biomasa de ambas especies, estimada por el método acústico, se observó que V. lucetia es uno de los principales componentes en el sistema de la Corriente de Humboldt de Perú y sus patrones de distribución y movimientos espacio-temporal están fuertemente relacionados a los desplazamientos migratorios del calamar. Estas relaciones tróficas promueven un incremento de la biomasa de D. gigas que es resultado de un patrón similar en V. lucetia, lo que propicia un efecto trófico positivo en el ecosistema oceánicoThis article is partly based on the PhD thesis in Marine Science of Rigoberto Rosas Luis. His doctoral degree is supported by CONACyT (Consejo Nacional de Ciencia y Tecnología, México).Peer reviewe

Anti-proliferative synergy of lysophospholipid analogues and ketoconazole against Trypanosoma cruzi (Kinetoplastida: Trypanosomatidae): cellular and ultrastructural analysis

Submitted by Sandra Infurna ([email protected]) on 2019-12-10T17:33:52Z No. of bitstreams: 1 RicardoSantaRita_HeleneBarbosa_etal_IOC_2005.pdf: 239835 bytes, checksum: 1dc2d1230a3762a8343f54772eb4e797 (MD5)Approved for entry into archive by Sandra Infurna ([email protected]) on 2019-12-10T17:46:02Z (GMT) No. of bitstreams: 1 RicardoSantaRita_HeleneBarbosa_etal_IOC_2005.pdf: 239835 bytes, checksum: 1dc2d1230a3762a8343f54772eb4e797 (MD5)Made available in DSpace on 2019-12-10T17:46:02Z (GMT). No. of bitstreams: 1 RicardoSantaRita_HeleneBarbosa_etal_IOC_2005.pdf: 239835 bytes, checksum: 1dc2d1230a3762a8343f54772eb4e797 (MD5) Previous issue date: 2005Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Departmento de Ultra-estrutura e Biologia Celular. Rio de Janeiro, RJ, Brasil.Instituto Venezolano de Investigaciones Científicas. Centro de Biofísica y Bioquímica. Laboratório de Química Biológica. Caracas, Venezuela.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Departmento de Ultra-estrutura e Biologia Celular. Rio de Janeiro, RJ, Brasil.Instituto Venezolano de Investigaciones Científicas. Centro de Biofísica y Bioquímica. Laboratório de Química Biológica. Caracas, Venezuela.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Departmento de Ultra-estrutura e Biologia Celular. Rio de Janeiro, RJ, Brasil.Objectives: Investigation of the antiproliferative synergy of the lysophospholipid analogues (LPAs) edelfosine, ilmofosine and miltefosine with the ergosterol biosynthesis inhibitor ketoconazole against Trypanosoma cruzi. Methods: The effect of LPAs, ketoconazole and their combination was evaluated against epimastigotes and intracellular amastigotes by the parameter IC50 leading to construction of isobolograms, for determination of a synergic effect. For epimastigotes, ultrastructural damage induced by these treatments was evaluated by transmission and scanning electron microscopy. Results: Synergy was confirmed against both epimastigotes and amastigotes of the parasite. Edelfosine or ketoconazole alone induced morphological alterations in the plasma membrane and reservosomes of the parasites, while in combination, they also led to severe mitochondrial damage, formation of autophagic structures and multinucleation. Scanning electron microscopy confirmed the effect at the plasma membrane and also revealed alterations in the shape of the parasites. Conclusions: Our results describe the synergic anti-proliferative effect of LPAs and ketoconazole against epimastigotes and intracellular amastigotes and suggest that in epimastigotes, plasma membrane, reservosomes and mitochondria are targets of these drugs, possibly by interference with lipid metabolism