Recovery of active pathogenesis-related enzymes from the apoplast of Musa acuminata infected by Mycosphaerella fijiensis

The fungus Mycosphaerella fijiensis causes black Sigatoka (BS) disease, a major pathogen in the banana industry worldwide. Numerous molecular and biochemical studies have been done for the M. fijiensis, Musa acuminata interaction, but this is the first study describing the zymographic behavior of β-1,3-glucanase, chitinase and protease in the apoplast and symplast of healthy, BS-infected but asymptomatic and BS diseased banana leaves. In BS-infected tissues, β-1,3-glucanase enzymatic activity was associated with two polypeptides with retention index (Ri) values of 0.43 and 0.56. These were more notable in the apoplast than in the symplast. Chitinase activity in BS-infected tissue in both the apoplast and symplast was mainly associated with a single polypeptide (Ri = 0.89). Both β-1,3-glucanase and chitinase activities were apparently more intense in BS-infected leaves than in healthy leaves. Protease activity was associated with two polypeptides (Ri = 0.04 and 0.14). In both the apoplast and symplast, the Ri 0.04 polypeptide increased in intensity with disease progression, whereas Ri 0.14 polypeptide intensity decreased. Overall protease activity intensity was higher in the symplast. Maximum symplast contamination of the apoplast was 2% as estimated by glucose 6-phosphate dehydrogenase activity, a biochemical marker for symplast. Accumulation of pathogenesis-related enzymatic activities in the apoplast of M. acuminata leaf tissue was caused by hostcontrolled enzyme downloading in response to M. fijiensis infection. Clear differences were identified in the electrophoretic profiles of healthy and diseased banana plants. The results further support a putative role of these enzymes in the extracellular defense repertoire of banana and, more importantly, suggest that M. fijiensis possesses a mechanism for suppression and delay of defense response in M. acuminata.Key words: Black Sigatoka, glucose 6-phosphate dehydrogenase, pathogenesis-related (PR) proteins, polyacrylamide gel electrophoresis (PAGE), retention index (Ri), sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE)

Habitat expansion of a tropical chironomid by seasonal alternation in use of littoral and profundal zones

The consistent warming of tropical lakes at all depths causes rapid development and long persistence of seasonal anoxia in the hypolimnion, which greatly reduces the biodiversity of hypolimnetic benthic invertebrates. Full mixing of the water column in a typically annual cool-season creates a benthic habitat suitable for invertebrates but offers little time for colonization before the return of anoxia. In Lake Alchichica, Mexico, the endemic midge Chironomus alchichica has evolved a life cycle consisting of reproduction in waters of the littoral zone, which is suboptimal for development, followed by colonization of the hypolimnetic benthic zone during its oxic phase. As shown by the sampling of both littoral and benthic habitats over an annual cycle, the development of Ch. alchichica in the profundal zone is favoured by minimal competition (only one other invertebrate species present) and no significant predation. The rapid maturation of the midge leads to a high density of pupation before the seasonal anoxia

Stabilization of apoptotic cells: generation of zombie cells

This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivs 3.0 Unported License.Apoptosis is characterized by degradation of cell components but plasma membrane remains intact. Apoptotic microtubule network (AMN) is organized during apoptosis forming a cortical structure beneath plasma membrane that maintains plasma membrane integrity. Apoptotic cells are also characterized by high reactive oxygen species (ROS) production that can be potentially harmful for the cell. The aim of this study was to develop a method that allows stabilizing apoptotic cells for diagnostic and therapeutic applications. By using a cocktail composed of taxol (a microtubule stabilizer), Zn2+ (a caspase inhibitor) and coenzyme Q10 (a lipid antioxidant), we were able to stabilize H460 apoptotic cells in cell cultures for at least 72 h, preventing secondary necrosis. Stabilized apoptotic cells maintain many apoptotic cell characteristics such as the presence of apoptotic microtubules, plasma membrane integrity, low intracellular calcium levels and mitochondrial polarization. Apoptotic cell stabilization may open new avenues in apoptosis detection and therapy.This work was supported by FIS PI10/00543 grant, Ministerio de Sanidad, Spain, and Fondo Europeo de Desarrollo Regional (FEDER-Unión Europea), SAS 111242 grant, Servicio Andaluz de Salud-Junta de Andalucía, Proyecto de Investigación de Excelencia de la Junta de Andalucía CTS-5725, BFU2012-38208 and by AEPMI (Asociación de Enfermos de Patología Mitocondrial).Peer Reviewe

Apoptotic cells subjected to cold/warming exposure disorganize apoptotic microtubule network and undergo secondary necrosis

Apoptotic microtubule network (AMN) is organized during apoptosis, forming a cortical structure beneath the plasma membrane which plays a critical role in preserving cell morphology and plasma membrane integrity. The aim of this study was to examine the effect of cold/warming exposure on apoptotic microtubules and plasma membrane integrity during the execution phase of apoptosis. We demonstrated in camptothecin-induced apoptotic H460 cells that cold/warming exposure disorganized apoptotic microtubules and allowed the access of active caspases to the cellular cortex and the cleavage of essential proteins in the preservation of plasma membrane permeability. Cleavage of cellular cortex and plasma membrane proteins, such as ¿-spectrin, paxilin, focal adhesion kinase and calcium ATPase pump (PMCA-4) involved in cell calcium extrusion resulted in increased plasma permeability and calcium overload leading apoptotic cells to secondary necrosis. The essential role of caspase-mediated cleavage in this process was demonstrated because the addition of the pan-caspase inhibitor z-VAD during cold/warming exposure that induces AMN depolymerization avoided the cleavage of cortical and plasma membrane proteins and prevented apoptotic cells to undergo secondary necrosis. Likewise, apoptotic microtubules stabilization by taxol during cold/warming exposure also prevented cellular cortex and plasma membrane protein cleavage and secondary necrosis. Furthermore, microtubules stabilization or caspase inhibition during cold/warming exposure was also critical for proper phosphatidylserine externalization and apoptotic cell clearance by macrophages. These results indicate that cold/warming exposure of apoptotic cells induces secondary necrosis which can be prevented by both, microtubule stabilization or caspase inhibition.This work was supported by FIS PI10/00543 Grant, FIS EC08/00076 Grant, Ministerio de Sanidad, Spain and Fondo Europeo de Desarrollo Regional (FEDER-Unión Europea), SAS 111242 Grant, Servicio Andaluz de Salud-Junta de Andalucía, Proyecto de Investigación de Excelencia de la Junta de Andalucía CTS-5725, and by Asociación de Enfermos de Patología Mitocondrial (AEPMI).Peer Reviewe

Critical role of AMP-activated protein kinase in the balance between mitophagy and mitochondrial biogenesis in MELAS disease

MELAS syndrome is a mitochondrial disorder that is caused mainly by the m.3243A > G mutation in mitochondrial DNA. Here, we report on how the severity of pathophysiological alterations is differently expressed in fibroblasts derived from patients with MELAS disease. We evaluated mitophagy activation and mitochondrial biogenesis which are the main mechanisms regulating the degradation and genesis of mitochondrial mass in MELAS fibroblasts and transmitochondrial cybrids. Our results suggest a critical balance between mitophagy and mitochondrial biogenesis which leads to the expression of different degrees of pathological severity among MELAS fibroblast cell lines according to their heteroplasmy load and the activation of AMP-activated protein kinase (AMPK). AMPK-activators such as 5-aminoimidazole-4-carboxamide 1-β-D-ribofuranoside (AICAR) or coenzyme Q10 (CoQ) increased peroxisome proliferator-activated receptor alpha (PGC-1α) nuclear translocation, mitochondrial biogenesis, antioxidant enzyme system response, autophagic flux and improved pathophysiological alterations in MELAS fibroblasts with the most severe phenotype. Our findings support the hypothesis that mitochondrial biogenesis, increased antioxidant response and autophagy clearance serve as compensatory mechanisms in response to mitophagic degradation of dysfunctional mitochondria and point out that AMPK is an important player in this balance.This work was supported by FIS PI13/00129 grant, Ministerio de Sanidad, Spain and Fondo Europeo de Desarrollo Regional (FEDER-Unión Europea), Proyecto de Investigación de Excelencia de la Junta de AndalucíaCTS-5725, and by AEPMI (Asociación de Enfermos de Patología Mitocondrial).Peer Reviewe

Multi-technical approach for the characterization of polychrome decorative surfaces at Spanish Mission Churches in Nueva Vizcaya (Chihuahua, Mexico)

An interdisciplinary and multi-institutional group of science and art conservation specialists has provided new insight into the painting materials used in the polychrome walls and wooden ceilings in four seventeenth century Spanish colonial churches of Nueva Vizcaya (Chihuahua, Mexico). A multi-analytical study of the decorative surfaces was performed in situ using spectroscopic approaches (XRF, FORS), False Colour Infrared Reflectography–IRFC, as well as micro sampling (ATR-FTIR, LM, GC/MS). A survey of natural resources and study (ATR-FTIR, LM) was carried out to elucidate the natural occurrence of a select number of materials in the surrounding areas of the churches. The present paper presents a multi-analytical study and characterization of green, red-orange and black colour pigments and binders selected from the decorative surfaces. The aim of this study is to highlight relationships between local materials and those from the original polychrome ceilings, in order to understand the material and technological influences that converged in the Spanish colonial architecture of northern Mexico

Multi-technical approach for the characterization of polychrome decorative surfaces at Spanish Mission Churches in Nueva Vizcaya (Chihuahua, Mexico)

An interdisciplinary and multi-institutional group of science and art conservation specialists has provided new insight into the painting materials used in the polychrome walls and wooden ceilings in four seventeenth century Spanish colonial churches of Nueva Vizcaya (Chihuahua, Mexico). A multi-analytical study of the decorative surfaces was performed in situ using spectroscopic approaches (XRF, FORS), False Colour Infrared Reflectography - IRFC, as well as micro sampling (ATR-FTIR, LM, GC/MS). A survey of natural resources and study (ATR-FTIR, LM) was carried out to elucidate the natural occurrence of a select number of materials in the surrounding areas of the churches. The present paper presents a multi-analytical study and characterization of green, red-orange and black colour pigments and binders selected from the decorative surfaces. The aim of this study is to highlight relationships between local materials and those from the original polychrome ceilings, in order to understand the material and technological influences that converged in the Spanish colonial architecture of northern Mexico

Amitriptyline induces mitophagy that precedes apoptosis in human HepG2 cells

Systemic treatments for hepatocellular carcinoma (HCC) have been largely unsuccessful. This study investigated the antitumoral activity of Amitriptyline, a tricyclic antidepressant, in hepatoma cells. Amitriptyline-induced toxicity involved early mitophagy activation that subsequently switched to apoptosis. Amitriptyline induced mitochondria dysfunction and oxidative stress in HepG2 cells. Amitriptyline specifically inhibited mitochondrial complex III activity that is associated with decreased mitochondrial membrane potential (ΔΨm) and increased reactive oxygen species (ROS) production. Transmission electron microscopy (TEM) studies revealed structurally abnormal mitochondria that were engulfed by double-membrane structures resembling autophagosomes. Consistent with mitophagy activation, fluorescence microscopy analysis showed mitochondrial Parkin recruitment and colocalization of mitochondria with autophagosome protein markers. Pharmacological or genetic inhibition of autophagy exacerbated the deleterious effects of Amitriptyline on hepatoma cells and led to increased apoptosis. These results suggest that mitophagy acts as an initial adaptive mechanism of cell survival. However persistent mitochondrial damage induced extensive and lethal mitophagy, autophagy stress and autophagolysome permeabilization leading eventually to cell death by apoptosis. Amitriptyline also induced cell death in hepatoma cells lines with mutated p53 and non-sense p53 mutation. Our results support the hypothesis that Amitriptyline-induced mitochondrial dysfunction can be a useful therapeutic strategy for HCC treatment, especially in tumors showing p53 mutations and/or resistant to genotoxic treatments.This work was supported by FIS PI13/00129 grant, Ministerio de Sanidad, Spain and Fondo Europeo de Desarrollo Regional (FEDER-Unión Europea), Proyecto de Investigación de Excelencia de la Junta de Andalucía CTS-5725, AEPMI (Asociación de Enfermos de Patología Mitocondrial) and ENACH (Asociación de Enfermedades Neurodegenerativas por Acumulación Cerebral de Hierro).Peer Reviewe

Las escalas de calidad de vida familiar (cdvf-e). Apoyo y orientación para la intervención

The aim of this paper is to present cDVF-E scales for families with children of 0-18 years, on one hand, and over 18 years, on the other, that researchers from five spanish universities have recently validated and standardized to the spanish population. To this end, first, the importance of the construct of quality of family life and its implications for research and practice should be emphasized. Afterwards, we introduce the first international initiatives measuring the quality of family life developed in the first decade of this century. Then the features, dimensions and psychometric properties of the scales are synthetically presented. Finally, the authors encourage practitioners and organizations to use these tools in the context of family-centered model and provides, as a conclusions, some consideration