Fire and resprouting in Mediterranean ecosystems: Insights from an external biogeographical region, the mexical shrubland

7 páginas, 3 tablas.We investigated modes of regeneration of dominant species of the mexical vegetation after fire. The mexical shrubland shows a remarkable structural, morphological, and floristic similarity to Mediterranean-type vegetation and is considered a relict of the Madro-Tertiary Geoflora under a non- mediterranean climate. This vegetation provides an ideal scenario to test the role of fire in Mediterranean ecosystems because historical fire occurrence is absent and the species assembly is constituted mostly by Madro-Tertiary elements and Neotropical species (some of them, endemic species from Mexico). The existence of congeneric species of the California chaparral allows us to determine the regeneration ability of these communities after fire in relation to resprouting and seeding strategies, which are widespread modes reported in the Mediterranean-type vegetation. By the experimental application of fire in the two biogeographical groups of species, we tested the hypothesis that low resprouting ability of California congeneric species (Madro-Tertiary species) after fire would indicate that fire has played an important selective force in the resprouting habit. A low resprouting ability in the Neotropical group of species would suggest that fire has molded the set of species dominating fire-prone environments. Our results indicated that resprouting is a widespread trait in the mexical species characterized by the presence of lignotubers and burls. Resprouting can be considered an ancient trait, probably linked to losses of aboveground biomass, that became a pre-adaptation in Mediterranean fire-prone communities. The Neotropical group of species showed less ability to regenerate after fire, and small plants were more likely to die after disturbance in this group than in the Madro-Tertiary group. The resprouting feature and the seeder strategy of other species after a fire in the mexical shrubland are similar to Mediterranean-type ecosystems, emphasizing their common origin and the relevance of phylogenetic and biogeographical studies to explain current patterns of vegetation.Peer reviewe

CoQ deficiency causes disruption of mitochondrial sulfide oxidation, a new pathomechanism associated with this syndrome

Coenzyme Q (CoQ) is a key component of the mitochondrial respiratory chain, but it also has several other functions in the cellular metabolism. One of them is to function as an electron carrier in the reaction catalyzed by sulfide:quinone oxidoreductase (SQR), which catalyzes the first reaction in the hydrogen sulfide oxidation pathway. Therefore, SQR may be affected by CoQ deficiency. Using human skin fibroblasts and two mouse models with primary CoQ deficiency, we demonstrate that severe CoQ deficiency causes a reduction in SQR levels and activity, which leads to an alteration of mitochondrial sulfide metabolism. In cerebrum of Coq9R239X mice, the deficit in SQR induces an increase in thiosulfate sulfurtransferase and sulfite oxidase, as well as modifications in the levels of thiols. As a result, biosynthetic pathways of glutamate, serotonin, and catecholamines were altered in the cerebrum, and the blood pressure was reduced. Therefore, this study reveals the reduction in SQR activity as one of the pathomechanisms associated with CoQ deficiency syndrome.Ministerio de Economía y CompetitividadERDF/SAF2013-47761-RERDF/SAF2014-55523-RERDF/RD12/0042/0011ERDF/SAF2015-65786-RJunta de AndalucíaNIH/P01HD08064

El control de la natalidad como expresión de violencia de género en China

Tras más de una treintena de años funcionando, a finales de 2015, el gobierno de la República Popular China finalizó la política del hijo único. Su puesta en práctica se basó en abortos forzosos, uso obligatorio de métodos anticonceptivos y esterilizaciones a hombres y mujeres. El legado que deja son 400 millones de niños no nacidos, el envejecimiento de la población y el desequilibrio demográfico entre sexos. Entre sus daños colaterales, destaca el aumento del tráfico de mujeres y el secuestro de menores en el país, el turismo de natalidad a otros Estados y la “inexistencia” de millones de niños que no pudieron ser registrados por haber nacido fuera de la legalidad. Además, entendemos que esta política ha supuesto una gravísima expresión de violencia de género en una sociedad donde la mujer sigue siendo inferior al hombre en la vida cotidiana del hogar, en el acceso al mundo laboral cualificado y en el mundo de la política. La nueva política del segundo hijo es la solución del gobierno ante la problemática generada por las restricciones de natalidad. Deja una mayor libertad, pero, en su esencia, sigue manteniendo el enfoque paternalista y totalitario que ha prevalecido a lo largo de las casi cuatro últimas décadas.Universidad de Sevilla. Grado en Periodism

Intra-/perioperative Brachytherapie mittels Flab-Bestrahlungstechnik

Diese retrospektive Arbeit befasst sich mit Tumorpatienten, die in der Klinik und Poliklinik für Strahlentherapie — Radioonkologie — am Universitätsklinikum Münster eine Brachytherapie mittels Flab erhalten haben. Der Patientenstamm bestand aus 78 Personen, von denen 4 Patienten mangels ausreichender Nachbeobachtungsdaten von der Analyse ausgeschlossen wurden. Die Patienten waren bei der Flab-Einlage im Mittel 35.7 ± 20.9 Jahre alt. Die Nachbeobachtungszeit lag im Median bei 3.5 Jahren. Die lokale 5-Jahres-Rezidivfreiheitsrate betrug in dem vorliegenden selektierten Hochrisikokollektiv 64 %. Bei 8 % der Patienten kam es zu einem vorzeitigen Abbruch der Flab-Bestrahlung und bei 23 % war aufgrund von Nebenwirkungen im Anschluss eine Revision notwendig. Zusammenfassend kann man sagen, dass das Verfahren eine vielversprechende Technik ist, bei akzeptablen Nebenwirkungen und einer guten Durchführbarkeit für ein selektiertes Hochrisikokollektiv die lokale Kontrollrate zu verbessern

Bilateral Simultaneous Retinal Detachment in Pseudophakia

Cataract surgery is the most frequent surgical intervention, with approximately 700,000 operations per year in Germany alone. One of the most serious complications is retinal detachment, with a reported incidence rate of pseudophakic retinal detachment of 0.75-1.65%. We report the case of a patient who suffered from a simultaneous bilateral pseudophakic retinal detachment. Interestingly, the bilateral detachments in the left and the right eye started with only some hours' delay. He had no acute trigger for the retinal detachment and no risk factors besides the cataract surgery performed on both eyes some weeks earlier. Simultaneous bilateral retinal detachments will be more common, due to increasing numbers of cataract surgeries and the demographic development. We conclude that funduscopy should be regularly performed in mydriasis to avoid sight-threatening simultaneous bilateral retinal detachments

Bilateral Simultaneous Retinal Detachment in Pseudophakia

Cataract surgery is the most frequent surgical intervention, with approximately 700,000 operations per year in Germany alone. One of the most serious complications is retinal detachment, with a reported incidence rate of pseudophakic retinal detachment of 0.75-1.65%. We report the case of a patient who suffered from a simultaneous bilateral pseudophakic retinal detachment. Interestingly, the bilateral detachments in the left and the right eye started with only some hours' delay. He had no acute trigger for the retinal detachment and no risk factors besides the cataract surgery performed on both eyes some weeks earlier. Simultaneous bilateral retinal detachments will be more common, due to increasing numbers of cataract surgeries and the demographic development. We conclude that funduscopy should be regularly performed in mydriasis to avoid sight-threatening simultaneous bilateral retinal detachments

Rezidivierende Hämolysen und Eisenüberladung unklarer Genese

Vorgestellt wird der Fall eines 33-jährigen Mannes mit rezidivierenden Ikterusepisoden und Hämolysen seit der Kindheit, die lange als Morbus Meulengracht fehlgedeutet wurden. In der Folge entwickelten sich bei dem Patienten auch eine Splenomegalie und Gallensteine in Verbindung mit einer Eisenüberladung. Auf Basis gendiagnostischer Untersuchungen wurde eine hereditäre Xerozytose diagnostiziert, das heißt eine Erythrozytenmembranstörung, die rezidivierende Hämolysen verursacht. Die Diagnose der Xerozytose ist oft eine Herausforderung. Die Häufigkeit der Erkrankung wird möglicherweise unterschätzt, da eine mikroskopische Blutuntersuchung häufig keine typischen Befunde liefert. Zudem fällt der Eosin-5-Maleimid(EMA)-Test, der zur Diagnose anderer Erythrozytenmembranstörungen eingesetzt wird, normal aus. In Fällen von Splenomegalie, Eisenüberladung und rezidivierender Hämolyse oder im Falle eines klinisch diagnostizierten Morbus Meulengracht in Kombination mit einem der zuvor genannten Symptome sollten weiterführende Untersuchungen und gegebenenfalls auch eine gendiagnostische Abklärung erwogen werden.The case of a 33-year-old male with recurrent icterus and hemolysis since childhood that was long mistaken for Gilbert disease is presented. Subsequently, the patient also developed splenomegaly and gallstones together with iron overload. Genetic testing revealed the diagnosis of hereditary xerocytosis, which is an erythrocyte membrane disorder causing recurrent hemolysis. Xerocytosis is often challenging to diagnose and the frequency of the condition might be underestimated as there are often no typical findings in the microscopic differential blood count, and Eosin-5-maleimide dye (EMA) test, which is used to diagnose other erythrocyte membrane disorders, is normal. In cases of splenomegaly, iron overload and recurrent hemolysis, or in the case of a clinical diagnosis of Gilbert disease together with one of the above-mentioned symptoms, further investigations and possibly also genetic testing should be considered

Hypofibrinolysis in diabetes: a therapeutic target for the reduction of cardiovascular risk

An enhanced thrombotic environment and premature atherosclerosis are key factors for the increased cardiovascular risk in diabetes. The occlusive vascular thrombus, formed secondary to interactions between platelets and coagulation proteins, is composed of a skeleton of fibrin fibres with cellular elements embedded in this network. Diabetes is characterised by quantitative and qualitative changes in coagulation proteins, which collectively increase resistance to fibrinolysis, consequently augmenting thrombosis risk. Current long-term therapies to prevent arterial occlusion in diabetes are focussed on anti-platelet agents, a strategy that fails to address the contribution of coagulation proteins to the enhanced thrombotic milieu. Moreover, antiplatelet treatment is associated with bleeding complications, particularly with newer agents and more aggressive combination therapies, questioning the safety of this approach. Therefore, to safely control thrombosis risk in diabetes, an alternative approach is required with the fibrin network representing a credible therapeutic target. In the current review, we address diabetes-specific mechanistic pathways responsible for hypofibrinolysis including the role of clot structure, defects in the fibrinolytic system and increased incorporation of anti-fibrinolytic proteins into the clot. Future anti-thrombotic therapeutic options are discussed with special emphasis on the potential advantages of modulating incorporation of the anti-fibrinolytic proteins into fibrin networks. This latter approach carries theoretical advantages, including specificity for diabetes, ability to target a particular protein with a possible favourable risk of bleeding. The development of alternative treatment strategies to better control residual thrombosis risk in diabetes will help to reduce vascular events, which remain the main cause of mortality in this condition

The antioxidant Trolox restores mitochondrial membrane potential and Ca2+-stimulated ATP production in human complex I deficiency

Malfunction of mitochondrial complex I caused by nuclear gene mutations causes early-onset neurodegenerative diseases. Previous work using cultured fibroblasts of complex-I-deficient patients revealed elevated levels of reactive oxygen species (ROS) and reductions in both total Ca2+ content of the endoplasmic reticulum (ERCa) and bradykinin(Bk)-induced increases in cytosolic and mitochondrial free Ca2+ ([Ca2+]C; [Ca2+]M) and ATP ([ATP]C; [ATP]M) concentration. Here, we determined the mitochondrial membrane potential (Δψ) in patient skin fibroblasts and show significant correlations with cellular ROS levels and ERCa, i.e., the less negative Δψ, the higher these levels and the lower ERCa. Treatment with 6-hydroxy-2,5,7,8-tetramethylchromane-2-carboxylic acid (Trolox) normalized Δψ and Bk-induced increases in [Ca2+]M and [ATP]M. These effects were accompanied by an increase in ERCa and Bk-induced increase in [Ca2+]C. Together, these results provide evidence for an integral role of increased ROS levels in complex I deficiency and point to the potential therapeutic value of antioxidant treatment