Overexpression of ScMYBAS1 alternative splicing transcripts differentially impacts biomass accumulation and drought tolerance in rice transgenic plants.

Drought is the most significant environmental stress for agricultural production worldwide, and tremendous efforts have been made to improve crop yield under the increasing water scarcity. Transcription factors are major players in the regulation of water stress-related genes in plants. Recently, different MYB transcription factors were characterized for their involvement in drought response. A sugarcane R2R3-MYB gene (ScMYBAS1) and its four alternative forms of transcript (ScMYAS1-2, ScMYBAS1-3, ScMYBAS1-4 and ScMYBAS1-5) were identified in this study. The subcellular localization, in Nicotiniana benthamiana, of the TFs fused in frame with GFP revealed that ScMYBAS1-2-GFP and ScMYBAS1-3-GFP were observed in the nucleus. The overexpression of ScMYBAS1-2 and ScMYBAS1-3 spliced transcripts in rice promoted change in plant growth under both well-watered and drought conditions. The ScMYBAS1-2 and ScMYBAS1-3 transgenic lines revealed a higher relative water content (RWC) compared to the wild type before maximum stress under drought conditions. The ScMYBAS1-2 transgenic lines showed a reduction in biomass (total dry weight). Conversely, ScMYBAS1-3 showed an increased biomass (total dry weight) relative to the wild-type. The overexpression of ScMYBAS1-3 in rice transgenic lines showed involvement with drought tolerance and biomass and, for this reason, was considered a good target for plant transformation, particularly for use in developing genotypes with drought tolerance and biomass accumulation.

Cerebrum-cervical arterial dissection in adults during sports and recreation / Dissecção arterial cérebro-cervical em adultos durante prática de esportes e recreação

Dissection of cervical arteries constitutes a medical emergency. Although relatively rarely, activities classified as sports and recreation may be a cause of arterial dissection independently of neck or head trauma. The purpose of the present paper was to present a series of cases of cerebrum-cervical arterial dissection in individuals during or soon after the practice of these sports activities. Methods Retrospective data on patients with arterial dissection related to sports and recreation. Results Forty-one cases were identified. The most frequently affected vessel was the vertebral artery. A large variety of activities had a temporal relationship to arterial dissection, and jogging was the most frequent of these. This is the largest case series in the literature. Conclusion Arterial dissection may be a complication from practicing sports.

A dissecção das artérias cervicais é uma emergência médica. Embora de forma relativamente rara, certas atividades descritas como esportes e recreação podem ser a causa de dissecção arterial independentemente de trauma de crânio ou cervical. O propósito do presente estudo é apresentar uma série de casos de dissecção de artérias cérebro-cervicais em indivíduos durante ou logo após a prática destas atividades desportivas. Métodos Dados retrospectivos de pacientes com dissecção arterial relacionada à prática de esportes e recreação. Resultados Quarenta e um casos foram identificados. A artéria mais frequentemente afetada foi a vertebral. Uma grande variedade de atividades teve relação temporal com a dissecção arterial, sendo a corrida a mais frequente delas. Esta é a maior série de casos da literatura. Conclusão Dissecção arterial pode ser uma complicação da prática de esportes.

Cerebrum-cervical arterial dissection in adults during sports and recreation.

UNLABELLED: Dissection of cervical arteries constitutes a medical emergency. Although relatively rarely, activities classified as sports and recreation may be a cause of arterial dissection independently of neck or head trauma. The purpose of the present paper was to present a series of cases of cerebrum-cervical arterial dissection in individuals during or soon after the practice of these sports activities. METHODS: Retrospective data on patients with arterial dissection related to sports and recreation. RESULTS: Forty-one cases were identified. The most frequently affected vessel was the vertebral artery. A large variety of activities had a temporal relationship to arterial dissection, and jogging was the most frequent of these. This is the largest case series in the literature. CONCLUSION: Arterial dissection may be a complication from practicing sports.

Interaction of P2 purinergic receptors with cellular macromolecules.

Ionotropic P2X and metabotropic P2Y receptors interact with a number of macromolecules in the cell membrane which may contribute to their functional plasticity. P2X receptors are homomeric or heteromeric assemblies of three subunits. P2Y receptors may form oligomeric complexes either with the same or with other P2Y receptor types. Although the signalling mechanism of P2X receptor channels is fast (within milliseconds) and relatively simple, by originating from the opening of an ion channel permeable to mono- and divalent cations, various macromolecules may modify the trafficking of these receptors to and from the cell membrane, as well as their activation and desensitization kinetics, and the possible opening of membrane pores induced by long-lasting exposure to agonists. P2X and Cys-loop receptors may physically interact with each other, resulting in mutual current occlusion. Heteromeric P2Y receptors may, via G(s), G(q/11) or G(i/o) protein-coupling and activation of the respective transduction mechanisms, mediate responses in the range of a few seconds. However, P2Y receptors may also interact with the signalling cascade of, e.g. receptor tyrosine kinases, and thereby mediate responses on a much slower time scale (within hours to days). In addition, P2Y receptors may interact with small, homomeric G proteins, integrins, and PDZ proteins. Eventually, P2Y receptors may cross-talk via Galpha-dependent signalling with other G protein-coupled receptors and via Gbetagamma (or indirectly Galpha)-dependent signalling with various ion channels. Thus, the activation of P2X and P2Y receptors by extracellular adenosine triphosphate/adenosine diphosphate or uridine triphosphate/uridine diphosphate may trigger specific chains of events which interact at the level of the individual elements both with each other and with the transduction mechanisms of other receptors, creating a huge diversity of the possible effects.