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1.
Ann Bot ; 123(1): 133-143, 2019 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-30137225

RESUMEN

Background and Aims: Fleshy structures that promote biotic dispersal by ingestion have evolved many times in seed plants. Within the yew family Taxaceae sensu lato (six genera, including Cephalotaxus), it remains controversial whether the characteristic fleshy structure surrounding the seed is interpreted as a novel outgrowth of the base of the ovule (i.e. an aril) or a fleshy seed coat that is entirely derived from the integument (i.e. a sarcotesta). This paper presents a detailed study of both wild-type and teratological seed cones of Pseudotaxus chienii, including morphology, anatomy and ontogeny. Methods: Wild-type and teratological seed cones were investigated with the classical paraffin technique and subsequent astrablue/safranin staining and scanning electron microscopy. Key Results: The wild-type seed cone of Pseudotaxus possesses a fleshy white aril that is cup-like and not entirely fused to the seed. In the teratological seed cones investigated, the aril was bilobed and consisted of two free halves. In both wild-type and teratological cones, the aril was initiated as two lateral primordia in a transverse plane, but in wild-type cones the two primordia became extended into a ring primordium, which grew apically, leading to the cup-like shape. The teratological seed cones lacked a ring primordium and the two lateral aril lobes remained free throughout their entire ontogeny, alternating with the scale-like leaves inserted below them on the same branch; in some cases, these leaves also became fleshy. Conclusions: Based on the ontogeny and arrangement of the two fleshy aril lobes in the teratological seed cones of Pseudotaxus, we suggest that the typical aril of Taxaceae could be readily interpreted as a fused pair of strongly swollen leaves rather than a modified integument. Our investigations of the cup-like aril of Pseudotaxus demonstrate a similarity not only with other Taxaceae but also with relatively distantly related conifers such as Phyllocladus (Podocarpaceae).


Asunto(s)
Evolución Biológica , Frutas/anatomía & histología , Taxaceae/anatomía & histología , Frutas/crecimiento & desarrollo , Frutas/ultraestructura , Microscopía Electrónica de Rastreo , Taxaceae/crecimiento & desarrollo , Taxaceae/ultraestructura
2.
Plant Cell Environ ; 41(7): 1683-1697, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-29664115

RESUMEN

Morphology, anatomy and physiology of sun and shade leaves of Abies alba were investigated and major differences were identified, such as sun leaves being larger, containing a hypodermis and palisade parenchyma as well as possessing more stomata, while shade leaves exhibit a distinct leaf dimorphism. The large size of sun leaves and their arrangement crowded on the upper side of a plagiotropic shoot leads to self-shading which is explainable as protection from high solar radiation and to reduce the transpiration via the lamina. Sun leaves furthermore contain a higher xanthophyll cycle pigment amount and Non-Photochemical Quenching (NPQ) capacity, a lower amount of chlorophyll b and a total lower chlorophyll amount per leaf, as well as an increased electron transport rate and an increased photosynthesis light saturation intensity. However, sun leaves switch on their NPQ capacity at rather low light intensities, as exemplified by several parameters newly measured for conifers. Our holistic approach extends previous findings about sun and shade leaves in conifers and demonstrates that both leaf types of A. alba show structural and physiological remarkable similarities to their respective counterparts in angiosperms, but also possess unique characteristics allowing them to cope efficiently with their environmental constraints.


Asunto(s)
Abies/anatomía & histología , Hojas de la Planta/anatomía & histología , Abies/fisiología , Abies/ultraestructura , Clorofila/metabolismo , Oscuridad , Microscopía Electrónica de Rastreo , Hojas de la Planta/fisiología , Hojas de la Planta/ultraestructura , Estomas de Plantas/fisiología , Estomas de Plantas/ultraestructura , Luz Solar
3.
Data Brief ; 52: 109964, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38235182

RESUMEN

The data presented were sourced from 34,884 commercial smart heat meters and 10,765 commercial smart water meters, spanning a timeframe of up to 5 years (2018-2022). All data primarily originated from single-family houses in Aalborg Municipality, Denmark. Furthermore, comprehensive building characteristics were collected for each building, where available, from the Danish Building and Dwelling Register (BBR) and Energy Performance Certificate (EPC) input data. This effort yielded an extensive pool of up to 86 distinct characteristics per building. All smart meter data were processed employing a well-established methodology, resulting in equidistant hourly data without any erroneous or missing values. The building characteristics derived from the EPCs were additionally filtered using rule sets to improve the data quality. This dataset holds substantial value for researchers involved in the domains of the built environment, district heating, and water sectors.

4.
Data Brief ; 54: 110326, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38590615

RESUMEN

The operational building data presented in this paper has been collected from six office rooms located in an office building (research and educational purposes) located on the main campus of Aalborg University in Denmark. The dataset consists of measurements of occupancy, indoor environmental quality, room-level and system-level heating, ventilation and lighting operation at a 5 min resolution. The indoor environmental quality and building system data were collected from the building management system. The occupancy level in each monitored room is established from the computer vision-based analysis of wall-mounted camera footage of each office. The number of people present in the room is estimated using the YOLOv5s image recognition algorithm. The present dataset can be used for occupancy analysis, indoor environmental quality investigations, machine learning, and model predictive control.

5.
Life Sci Alliance ; 2(5)2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-31455669

RESUMEN

ADAM17, prominent member of the "Disintegrin and Metalloproteinase" (ADAM) family, controls vital cellular functions through cleavage of transmembrane substrates. Several of these play central roles in oncogenesis and inflammation, yet despite its importance, the mechanism by which ADAM17 is activated is not fully understood. We recently presented evidence that surface exposure of phosphatidylserine (PS) is the penultimate event required for sheddase activation, which occurs upon binding of a membrane-proximal, cationic binding motif to the anionic phospholipid headgroup. Here, we show that mutagenesis of the 3 amino acids constituting the PS-binding motif leads to embryonic lethality in mice. Heterozygotes showed no abnormalities. Primary hepatocytes and fibroblasts were analysed and found to express the mutant protease on the cell surface. However, PMA-stimulated release of ADAM17 substrates was completely abolished. The results directly support the novel concept of transiently externalised PS as essential trigger of extracellular protease function in vivo.


Asunto(s)
Proteína ADAM17/química , Proteína ADAM17/genética , Mutación , Fosfatidilserinas/metabolismo , Proteína ADAM17/metabolismo , Animales , Sitios de Unión , Fibroblastos/citología , Fibroblastos/efectos de los fármacos , Fibroblastos/metabolismo , Genes Letales , Hepatocitos/citología , Hepatocitos/efectos de los fármacos , Hepatocitos/metabolismo , Ratones , Cultivo Primario de Células , Acetato de Tetradecanoilforbol/análogos & derivados , Acetato de Tetradecanoilforbol/farmacología
6.
J Mol Cell Biol ; 11(11): 979-993, 2019 12 23.
Artículo en Inglés | MEDLINE | ID: mdl-30753537

RESUMEN

Dysregulation of the disintegrin-metalloproteinase ADAM10 may contribute to the development of diseases including tumorigenesis and Alzheimer's disease. The mechanisms underlying ADAM10 sheddase activation are incompletely understood. Here, we show that transient exposure of the negatively charged phospholipid phosphatidylserine (PS) is necessarily required. The soluble PS headgroup was found to act as competitive inhibitor of substrate cleavage. Overexpression of the Ca2+-dependent phospholipid scramblase Anoctamin-6 (ANO6) led to increased PS externalization and substrate release. Transfection with a constitutively active form of ANO6 resulted in maximum sheddase activity in the absence of any stimulus. Calcium-dependent ADAM10 activation could not be induced in lymphocytes of patients with Scott syndrome harbouring a missense mutation in ANO6. A putative PS-binding motif was identified in the conserved stalk region. Replacement of this motif resulted in strong reduction of sheddase activity. In conjunction with the recently described 3D structure of the ADAM10 extracellular domain, a model is advanced to explain how surface-exposed PS triggers ADAM10 sheddase function.


Asunto(s)
Proteína ADAM10/metabolismo , Membrana Celular/metabolismo , Activación Enzimática , Proteína ADAM10/química , Secuencia de Aminoácidos , Animales , Anoctaminas/metabolismo , Biomarcadores , Células COS , Línea Celular , Chlorocebus aethiops , Eritrocitos/metabolismo , Humanos , Proteínas de la Membrana/metabolismo , Modelos Biológicos , Fosfoserina/metabolismo , Conejos , Relación Estructura-Actividad
7.
PeerJ ; 6: e4948, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29868298

RESUMEN

Both wild-type and teratological seed cones are described in the monoecious conifer Glyptostrobus pensilis and compared with those of other Cupressaceae sensu lato and other conifers. Some Cupressaceae apparently possess a proliferation of axillary structures in their cone scales. In our interpretation, in Glyptostrobus each bract of both typical and atypical seed cones bears two descending accessory shoots, interpreted here as seed scales (ovuliferous scales). The primary seed scale is fertile and forms the ovules, the second is sterile and forms characteristic tooth-like structures. The bract and the two axillary seed scales are each supplied with a single distinct vascular bundle that enters the cone axis as a separate strand; this vasculature also characterises the descending accessory short shoots in the vegetative parts of the crown. In wild-type seed cones, the fertile seed scale is reduced to its ovules, and the ovules are always axillary. In contrast, the ovules of some of the teratological seed cones examined were located at the centre of the cone scale. An additional tissue found on the upper surface of the sterile lower seed scale is here interpreted as the axis of the fertile seed scale. Thus, the central position of the ovules can be explained by recaulescent fusion of the upper fertile and lower sterile seed scales. In several teratological cone scales, the ovules were enveloped by an additional sterile tissue that is uniseriate and represents an epidermal outgrowth of the fertile seed scale. Close to the ovules, the epidermis was detached from lower tissue and surrounded the ovule completely, except at the micropyle. These teratological features are potentially significant in understanding seed-cone homologies among extant conifers.

8.
Biochim Biophys Acta Mol Cell Res ; 1865(11 Pt A): 1598-1610, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-30327201

RESUMEN

ADAM17, a prominent member of the "Disintegrin and Metalloproteinase" (ADAM) family, controls vital cellular functions through cleavage of transmembrane substrates including TGF-alpha, Amphiregulin (AREG) and TNF-Receptor 1 (TNFR1). We recently presented evidence that surface exposure of phosphatidylserine (PS) is pivotal for ADAM17 to exert sheddase activity. Anoctamin-6 (ANO6) has Ca2+-dependent phospholipid scramblase activity and it followed that the functions of ANO6 and ADAM17 might be linked. We report that overexpression of ANO6 in HEK293T cells led to increased Ca2+-mediated PS-exposure that was indeed accompanied by enhanced release of AREG and TGF-alpha. The effect was not observed when cells were treated with the PKC-dependent ADAM17 activator PMA. Transformation of cells with a constitutively active ANO6 mutant led to spontaneous PS-exposure and to the release of ADAM17-substrates in the absence of any stimuli. Inhibitor experiments indicated that ANO6-mediated enhancement of substrate cleavage simultaneously broadened the spectrum of participating metalloproteinases. In complementary experiments, siRNA-mediated downregulation of ANO6 was shown to decrease ionophore-mediated release of TNFR1 in human umbilical vein endothelial cells (HUVECs). We conclude that ANO6, by virtue of its scramblase activity, may play a role as an important regulator of the ADAM-network in the plasma membrane.


Asunto(s)
Proteínas ADAM/metabolismo , Anoctaminas/metabolismo , Fosfatidilserinas/metabolismo , Proteínas de Transferencia de Fosfolípidos/metabolismo , Fosfolípidos/metabolismo , Proteína ADAM17/metabolismo , Calcio/metabolismo , Membrana Celular/metabolismo , Regulación de la Expresión Génica , Células HEK293 , Humanos , Ionomicina/farmacología , Modelos Biológicos , Mutación , Factor de Crecimiento Transformador alfa/metabolismo
9.
Ann Surg ; 235(4): 560-7, 2002 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-11923613

RESUMEN

OBJECTIVE: To investigate whether monocyte paralysis resistant to interferon-gamma (IFN-gamma) costimulation may exist before surgery and postoperative infection and may correlate with the outcome of postoperative sepsis. SUMMARY BACKGROUND DATA: Several studies have correlated monocyte paralysis during the course of sepsis with lethal outcome. Although the authors' previous work indicated that preoperative defects in monocyte interleukin (IL)-12 production are associated with the development of severe postoperative sepsis, the functional state of monocytes before surgery and infection and its significance for sepsis requires further analysis. METHODS: In a prospective study, monocyte functions of 1,113 consecutive patients were examined before major visceral surgery. Monocytes were isolated from peripheral blood and were stimulated in vitro with IFN-gamma and lipopolysaccharide. The secretion of IL-12 p70, IL-12 p40, IL-10, and tumor necrosis factor was measured. RESULTS: Preoperative monocyte secretion of IL-12 p70 and IL-12 p40 was significantly reduced in patients who developed lethal postoperative sepsis compared with sepsis survivors and patients with uneventful postoperative recovery. Moreover, preoperative monocyte IL-12 production was an independent predictive factor for the lethal outcome of postoperative sepsis by multivariate analysis. Preoperative monocyte IL-10 production was impaired in the sepsis group but did not correlate with death from sepsis. Preoperative monocyte tumor necrosis factor secretion was comparable between patients with uneventful recovery, sepsis survivors, and nonsurvivors. Thus, impaired preoperative monocyte IL-12 secretion in patients developing lethal postoperative sepsis did not result from an overproduction of IL-10 or from a generalized monocyte paralysis. The association between impaired preoperative monocyte IL-12 production and death from sepsis was also not explained by gender differences, underlying malignant disease, tumor type, neoadjuvant therapy, or age. CONCLUSIONS: These results identify a selective preoperative defect in monocyte IL-12 production as a predictive factor for the lethal outcome of postoperative sepsis. These data suggest that a partial preoperative monocyte paralysis severely impairs the host defense against postoperative infection, resulting in an increased risk of lethal sepsis.


Asunto(s)
Adyuvantes Inmunológicos/metabolismo , Interleucina-12/metabolismo , Monocitos/metabolismo , Evaluación de Resultado en la Atención de Salud , Complicaciones Posoperatorias , Sepsis/mortalidad , Sepsis/fisiopatología , Anciano , Procedimientos Quirúrgicos del Sistema Digestivo/efectos adversos , Procedimientos Quirúrgicos Electivos/efectos adversos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Cuidados Preoperatorios , Estudios Prospectivos , Sepsis/etiología
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