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Diaz-Almeyda E.,National Autonomous University of Mexico | Thome P.E.,National Autonomous University of Mexico | Hafidi M.E.,Instituto Nacional Of Cardiologia Ignacio Chavez | Iglesias-Prieto R.,National Autonomous University of Mexico
Coral Reefs | Year: 2011

Coral reefs are threatened by increasing surface seawater temperatures resulting from climate change. Reef-building corals symbiotic with dinoflagellates in the genus Symbiodinium experience dramatic reductions in algal densities when exposed to temperatures above the long-term local summer average, leading to a phenomenon called coral bleaching. Although the temperature-dependent loss in photosynthetic function of the algal symbionts has been widely recognized as one of the early events leading to coral bleaching, there is considerable debate regarding the actual damage site. We have tested the relative thermal stability and composition of membranes in Symbiodinium exposed to high temperature. Our results show that melting curves of photosynthetic membranes from different symbiotic dinoflagellates substantiate a species-specific sensitivity to high temperature, while variations in fatty acid composition under high temperature rather suggest a complex process in which various modifications in lipid composition may be involved. Our results do not support the role of unsaturation of fatty acids of the thylakoid membrane as being mechanistically involved in bleaching nor as being a dependable tool for the diagnosis of thermal susceptibility of symbiotic reef corals. © 2010 Springer-Verlag.

Negrette-Guzman M.,National Autonomous University of Mexico | Tapia E.,Instituto Nacional Of Cardiologia Ignacio Chavez | Pedraza-Chaverri J.,National Autonomous University of Mexico
Free Radical Biology and Medicine | Year: 2013

The chemotherapeutic isothiocyanate sulforaphane (SFN) was early linked to anticarcinogenic and antiproliferative activities. Soon after, this compound, derived from cruciferous vegetables, became an excellent and useful trial for anti-cancer research in experimental models including growth tumor, metastasis, and angiogenesis. Many subsequent reports showed modifications in mitochondrial signaling, functionality, and integrity induced by SFN. When cytoprotective effects were found in toxic and ischemic insult models, seemingly contradictory behaviors of SFN were discovered: SFN was inducing deleterious changes in cancer cell mitochondria that eventually would carry the cell to death via apoptosis and also was protecting noncancer cell mitochondria against oxidative challenge, which prevented cell death. In both cases, SFN exhibited effects on mitochondrial redox balance and phase II enzyme expression, mitochondrial membrane potential, expression of the family of B cell lymphoma 2 homologs, regulation of proapoptotic proteins released from mitochondria, activation/inactivation of caspases, mitochondrial respiratory complex activities, oxygen consumption and bioenergetics, mitochondrial permeability transition pore opening, and modulation of some kinase pathways. With the ultimate findings related to the induction of mitochondrial biogenesis by SFN, it could be considered that SFN has effects on mitochondrial dynamics that explain some divergent points. In this review, we list the reports involving effects on mitochondrial modulation by SFN in anti-cancer models as well as in cytoprotective models against oxidative damage. We also attempt to integrate the data into a mechanism explaining the various effects of SFN on mitochondrial function in only one concept, taking into account mitochondrial biogenesis and dynamics and making a comparison with the theory of reactive oxygen species threshold of cell death. Our interest is to achieve a complete view of cancer and protective therapies based on SFN that can be extended to other chemotherapeutic compounds with similar characteristics. The work needed to test this hypothesis is quite extensive. © 2013 Elsevier Inc. All rights reserved.

Martinez-Lavin M.,Instituto Nacional Of Cardiologia Ignacio Chavez
Archivos de Cardiologia de Mexico | Year: 2012

Science is an ever-changing discipline. Modern medical knowledge is based on science. Current medical paradigm is both linear and reductionist. There is a new general theory validated by computer's calculations named chaos and complexity theory. This new paradigm will probably have an impact on medical practice. Cardiovascular physiology may display fractal and/ or chaotic behavior. Computerized heart rhythm analyses enhanced our understanding of complex diseases otherwise not explainable by current linear-reductionist paradigms. Cases in point are diverse dysautonomia including orthostatic intolerance, cardiac X syndrome and fibromyalgia. Derived from this, new knowledge is a different diagnostic and therapeutic stance: scientific holism.

Pineda C.,Instituto Nacional Of Rehabilitacion | Martinez-Lavin M.,Instituto Nacional Of Cardiologia Ignacio Chavez
Rheumatic Disease Clinics of North America | Year: 2013

This article presents an updated overview of hypertrophic osteoarthropathy and digital clubbing for the practicing rheumatologist. Discussion includes a brief historical perspective, its definition, incidence and prevalence, classification, pathology and pathophysiology, clinical manifestations, demographics, findings on physical examination, imaging techniques for its detection, differential diagnosis, and treatment modalities. © 2013 Elsevier Inc.

Yabur-Espitia M.,Instituto Nacional Of Cardiologia Ignacio Chavez
Revista médica del Instituto Mexicano del Seguro Social | Year: 2011

To describe the clinical behavior and the echocardiographic features of six patients with ventricular non-compaction associated to complex congenital heart disease. A complete clinical history and the echocardiographic study were performed in six patients with complex congenital heart disease. Jenni's criteria for the echocardiograph assessment of ventricular non compaction were used. In all cases prominent trabeculae and deep intertrabecular recesses in the ventricular wall filled by direct blood flow from the ventricular chamber were visualized by color Doppler imaging. The ratio of none compacted to compacted layer was of 2.5±0.19. The associated congenital heart diseases were: Ulh's anomaly, the absence of right atrioventricular connection, single ventricle, cleft of mitral valve, transposition of the great arteries, double inlet in left ventricle. The clinical manifestations were presented in the childhood and they were associated with congenital heart defect. The echocardiography is a diagnostic method which allows the assessment of the ventricular noncompaction.

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