20 research outputs found
Identification of a homolog of Arabidopsis DSP4 (SEX4) in chestnut: its induction and accumulation in stem amyloplasts during winter or in response to the cold_
Oligosaccharide synthesis is an important cryoprotection strategy used by woody plants during winter dormancy. At the onset of autumn, starch stored in the stem and buds is broken down in response to the shorter days and lower temperatures resulting in the buildup of oligosaccharides. Given that the enzyme DSP4 is necessary for diurnal starch degradation in Arabidopsis leaves, this study was designed to address the role of DSP4 in this seasonal process in Castanea sativa Mill. The expression pattern of the CsDSP4 gene in cells of the chestnut stem was found to parallel starch catabolism. In this organ, DSP4 protein levels started to rise at the start of autumn and elevated levels persisted until the onset of spring. In addition, exposure of chestnut plantlets to 4 °C induced the expression of the CsDSP4 gene. In dormant trees or cold-stressed plantlets, the CsDSP4 protein was immunolocalized both in the amyloplast stroma and nucleus of stem cells, whereas in the conditions of vegetative growth, immunofluorescence was only detected in the nucleus. The studies indicate a potential role for DSP4 in starch degradation and cold acclimation following low temperature exposure during activity–dormancy transition
Hemangiopericitoma pericárdico
Paciente varón de 31 años, diagnosticado de masa mediastínica. La resonancia nuclear magnética, la tomografía computarizada (Fig. 1) y ecocardiografía demostraron una masa mediastínica de 11 × 8 × 9 que comprimía aurícula izquierda, ventrículo izquierdo, aorta ascendente y venas pulmonares izquierdas. Se tomaron biopsias del tumor mediante toracoscopia. El análisis inmunohistológico (positivo para CD 34) (Fig. 2) y el estudio anatomopatológico de las piezas fue consistente con un hemangiopericitoma.
El tumor mediastínico fue extirpado bajo anestesia general, esternotomía media y circulación extracorpórea. La totalidad de la masa fue extraída junto con un parche de arteria pulmonar izquierda que se encontraba infiltrada en profundidad
Overall alteration of circadian clock gene expression in the chestnut cold response
Cold acclimation in woody plants may have special features compared to similar processes in herbaceous plants. Recent studies have shown that circadian clock behavior in the chestnut tree (Castanea sativa) is disrupted by cold temperatures and that the primary oscillator feedback loop is not functional at 4 degrees C or in winter. In these conditions, CsTOC1 and CsLHY genes are constantly expressed. Here, we show that this alteration also affects CsPRR5, CsPRR7 and CsPRR9. These genes are homologous to the corresponding Arabidopsis PSEUDO-RESPONSE REGULATOR genes, which are also components of the circadian oscillator feedback network. The practically constant presence of mRNAs of the 5 chestnut genes at low temperature reveals an unknown aspect of clock regulation and suggests a mechanism regulating the transcription of oscillator genes as a whole
The role of postmortem study in the diagnosis of the cause of death in a young man: a rare case of Ehlers–Danlos syndrome type IV
Diagnosis of the cause of death in young people is a challenge to both the clinician and the pathologist. Ehlers–Danlos syndrome (EDS) type IV is an inherited connective tissue disorder. It is characterised by thin translucent skin, abnormal fragility of blood vessels, and a typical facial appearance. The cause of death is usually due to large arterial rupture. We describe an unusual case of a 23-year-old man clinically diagnosed with myocarditis, who suffered from recurrent pulmonary haemorrhage and died of massive myocardial haemorrhage and ischaemia without coronary artery disease. Diagnosis of EDS type IV was made by autopsy. To our knowledge, this is the first such report in the literature. Delay in diagnosing this syndrome is common even when clinical features are typical, and the condition often goes unrecognised until necropsy. The diagnosis of EDS should be considered in young people who seek medical attention because of arterial rupture