RESUMEN
Epiphytes develop anatomical features to improve efficiency of the uptake of water and nutrients, such as absorptive foliar scales or a velamen radicum. Despite substantial studies on the occurrence, morphology, development and phylogeny of the velamen, most of the available literature is focused on Orchidaceae, making current knowledge on velamen clearly biased. A recent publication firmly established that velamina are common in Anthurium species. Thus, this study provides further insights by describing velamen morphological characteristics of Anthurium species and classifying them into different velamen types. Furthermore, we investigate if the different velamen morphological traits are clade-specific and phylogenetically conserved within the genus. Using SEM, we performed a morphological study on 89 Anthurium species, describing six micromorphological traits of velamen and exodermis, following traits used to classify Orchidaceae velamen by Porembski & Barthlott (1988). We distinguished nine velamen types, including two that are unique to Anthurium and not similar to any type found in Orchidaceae. Comparing velamen morphology within the phylogenetic tree of Anthurium revealed clear phylogenetic signals. This study provides detailed morphological descriptions among 89 species of Anthurium from the Araceae, and substantially broadens our knowledge of this tissue. However, velamen function has been even less studied, with hardly anything known about functional significance of having secondary cell wall thickening and perforations on velamen cell walls. Therefore, a logical next step would be to connect these anatomical features to their functions.
Asunto(s)
Araceae , Filogenia , Araceae/anatomía & histología , Araceae/genética , Microscopía Electrónica de RastreoRESUMEN
By exposing floating gates of EEPROM memory cells with frontside sample preparation, scanning nonlinear dielectric microscopy (SNDM) succeeded in reading back the data stored in the memory cells with a 250 nm node size. At an optimized voltage bias of AC = 3 V and DC = 1 V, a clear signal contrast between programmed and erased cells is obtained. The high resolution SNDM signal reveals the details of bowling-pin shape structure of memory cells, providing high confidence in data assignment during forensic applications. Such high resolution also makes SNDM a promising technique for newer generation devices with smaller node size.
RESUMEN
RANKL (receptor activator of nuclear factor kappaB ligand) promotes osteoclast differentiation, stimulates osteoclast activity, and prolongs osteoclast survival and adherence to bone. Abnormalities of the RANKL/RANK/osteoprotegerin system have been implicated in a range of diseases, including osteoporosis. To date, no work has been done in osteolytic lesions of the facial skeleton. In this study, specimens of ameloblastomas, dentigerous cysts, odontogenic keratocysts, and radicular cysts were subjected to immunohistochemical analysis for RANKL and tartrate-resistant acid phosphatase (TRAP). Immunofluorescence staining for TRAP was visualized under confocal microscopy. All specimens demonstrated distinct positive immunoreactivity to RANKL and TRAP. The TRAP-positive cells also stained with in situ hybridization for human calcitonin receptor, a definitive marker for osteoclasts. Mononuclear pre-osteoclasts were observed to migrate from blood to the connective tissue stroma and multinucleate toward the bone surface. It can be concluded that RANKL plays a role in bone resorption in osteolytic lesions of the facial skeleton.
Asunto(s)
Ameloblastoma/metabolismo , Glicoproteínas/metabolismo , Neoplasias Maxilomandibulares/metabolismo , Quistes Odontogénicos/metabolismo , Osteólisis/metabolismo , Receptores Citoplasmáticos y Nucleares/metabolismo , Fosfatasa Ácida/metabolismo , Quiste Dentígero/metabolismo , Huesos Faciales/metabolismo , Huesos Faciales/patología , Humanos , Inmunohistoquímica , Hibridación in Situ , Isoenzimas/metabolismo , Osteoprotegerina , Quiste Radicular/metabolismo , Receptores de Calcitonina/metabolismo , Receptores del Factor de Necrosis Tumoral , Transducción de Señal , Fosfatasa Ácida TartratorresistenteRESUMEN
A randomized clinical trial was conducted to investigate the effect of the presence of a pharyngeal pack during endotracheal anaesthesia on the incidence of postoperative sore throat. The patients were anaesthetized with fentanyl, thiopentone and atracurium. Thirty-six patients were anaesthetized without placement of pharyngeal packs while 26 patients had pharyngeal packs inserted. There were no significant differences in the incidence or severity of sore throat postoperatively in the two groups (P=0.23). These results contradict previous studies, which showed an increase in the incidence of postoperative sore throat after the use of pharyngeal packs.