Development of vascular elements during renal organogenesis

DNA synthesis starts earliest in the apical meristem of the shoot, and latest in the cotyledons. Mitoses appear simultaneously in the apical meristem and in the hypocotyl cortex. Synthesis continues in the mother cells of vascular elements and cotyledon parenchyma when mitosis ceases. In the cotyledons DNA synthesis is rather synchronous and leads to the elimination of 2 C nuclei.

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Prognostic of the Using Wood of Erythroxylum myrsinites Mart. Under the Anatomic Prism

Journal of Agricultural Science ◽

10.5539/jas.v12n1p188 ◽

2019 ◽

Vol 12 (1) ◽

pp. 188

Author(s):

Rossana Cortelini da Rosa ◽

Dione Dambrós Raddatz ◽

Paulo Fernando dos Santos Machado ◽

Mario Lima dos Santos ◽

Alexandro Dias Martins Vasconcelos ◽

...

Keyword(s):

Wood Properties ◽

Anatomical Structure ◽

Specific Mass ◽

Wood Technology ◽

Mechanical Loads ◽

Axial Parenchyma ◽

Thin Walls ◽

Gelatinous Fibers ◽

Vascular Elements ◽

High Flexibility

The composition of the wood and its elements are considered determinants in the wood properties, standing out the fibers, axial parenchyma, number of vessels and rays. In this context, we aimed to investigate and describe the wood anatomical structure of the Erythroxylum myrsinites Mart. and identify its potential uses in the area of wood technology. From the tree, were removed three wood samples for the confection of anatomical slides, witch 3 × 3 × 3 cm, oriented we plans transversal, longitudinal and tangential longitudinal. For the preparation of histological blades, the method of Burger and Richter was adopted; the anatomical description was based on IAWA Committee recommendations. The species presents vessels numerous, solitary, composing 19% of the volume of wood. Diffuse porosity of polygonal contour and thin walls. Mean vascular elements, axial parenchyma representing 3% of the volume of the wood, in a paratracheal vasicentric arrangement. The rays are numerous, occupying 23% of the volume of the wood, narrow and heterogeneous, consisting of procumbent, square and erect cells. The fibers are libriform, of length medium and thick walls, occupying 55% of the volume of the wood, have spiral thickening and septate fibers, absent tracheids, and gelatinous fibers abundant. The characteristics presented give high flexibility to the stem and branches, and the wood with low specific mass, permeable and resistant to mechanical loads has potential for use in energy generation.

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Effects of stimulation on steroid output and perfusion medium flow rate in the isolated perfused rat adrenal gland in situ

Journal of Endocrinology ◽

10.1677/joe.0.1090279 ◽

1986 ◽

Vol 109 (2) ◽

pp. 279-285 ◽

Cited By ~ 16

Author(s):

J. P. Hinson ◽

G. P. Vinson ◽

B. J. Whitehouse ◽

G. M. Price

Keyword(s):

Flow Rate ◽

Zona Glomerulosa ◽

Clear Correlation ◽

Perfusion Medium ◽

Flow Rates ◽

Vascular Elements ◽

Medium Flow ◽

High Concentrations ◽

Adrenal Vasculature

ABSTRACT Using the in-situ, isolated, perfused rat adrenal system, the actions of adrenal stimulants on steroidogenesis and perfusion medium flow rates (under constant perfusion pump conditions) have been studied. In a series of 100 experiments, initial rates of corticosterone output and flow rates were found to be positively correlated, although there was no such relationship between initial rates of aldosterone output and flow rates. Furthermore, in stable perfusion conditions, bolus injections of ACTH increased both flow rate and steroid output in a dose-related manner. In individual experiments there was a clear correlation between corticosterone and flow, but the association between aldosterone secretion rate and flow was less evident. It is possible that this discrepancy arises because of temporal differences in the responses of these two steroids. Flow was also stimulated by dibutyryl cyclic AMP (dbcAMP), with correlations with steroid output similar to ACTH, but the specific zona glomerulosa stimulants angiotensin II amide and potassium ions had, if anything, inhibitory effects on flow, but only at high concentrations. The data suggest that ACTH and dbcAMP evoke specific responses in the adrenal vasculature, resulting in relatively decreased intraglandular vascular resistance. They furthermore suggest that the secretory functions of the inner adrenocortical zones are subject to the additional control of vascular elements in the intact gland. J. Endocr. (1986) 109, 279–285

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Cytological Aspects of Compost-Mediated Induced Resistance Against Fusarium Crown and Root Rot in Tomato

Phytopathology ◽

10.1094/phyto.2002.92.4.424 ◽

2002 ◽

Vol 92 (4) ◽

pp. 424-438 ◽

Cited By ~ 78

Author(s):

Benoît Pharand ◽

Odile Carisse ◽

Nicole Benhamou

Keyword(s):

Induced Resistance ◽

Root Rot ◽

Disease Incidence ◽

Disease Suppression ◽

Gold Complex ◽

Peat Moss ◽

Fungal Colonization ◽

Pythium Oligandrum ◽

Vascular Elements ◽

Crown And Root Rot

The potential of a pulp and paper mill residues compost for the control of crown and root rot of greenhouse-grown tomato caused by Fusarium oxysporum f. sp. radicis-lycopersici was ultrastructurally investigated. Peat moss amended with compost substantially reduced disease-associated symptoms. Addition of Pythium oligandrum to either peat moss alone or peat moss amended with compost resulted in a considerable reduction in disease incidence compared with controls grown in peat moss alone. Histological and cytological observations of root samples from Fusarium-inoculated plants revealed that the beneficial effect of compost in reducing disease symptoms is associated with increased plant resistance to fungal colonization. One of the most prominent facets of compost-mediated induced resistance concerned the formation of physical barriers at sites of attempted fungal penetration. These structures, likely laid down to prevent pathogen ingress toward the vascular elements, included callose-enriched wall appositions and osmiophilic deposits around the sites of potential pathogen ingress. Invading hyphae, coated by the osmiophilic material, showed marked cellular disorganization. The use of the wheat germ agglutinin-ovomucoid-gold complex provided evidence that the wall-bound chitin was altered in severely damaged hyphae. A substantial increase in the extent and magnitude of the cellular changes induced by compost was observed when P. oligandrum was supplied to the potting substrate. This finding corroborates the current concept that amendment of composts with specific antagonists may be a valuable option for amplifying their beneficial properties in terms of plant disease suppression.

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Differentiation of Vascular Elements in Tissue Culture

Morphogenesis in Plant Tissue Cultures ◽

10.1007/978-94-015-9253-6_1 ◽

1999 ◽

pp. 3-35 ◽

Cited By ~ 1

Author(s):

G. Paul Bolwell ◽

Duncan Robertson

Keyword(s):

Tissue Culture ◽

Vascular Elements

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An Algorithmic Approach to Treating Lumbar Spinal Stenosis: An Evidenced-Based Approach

Pain Medicine ◽

10.1093/pm/pnz133 ◽

2019 ◽

Vol 20 (Supplement_2) ◽

pp. S23-S31

Author(s):

Sudhir Diwan ◽

Dawood Sayed ◽

Timothy R Deer ◽

Amber Salomons ◽

Kevin Liang

Keyword(s):

Spinal Stenosis ◽

Lumbar Spinal Stenosis ◽

Conservative Management ◽

Treatment Algorithm ◽

Decompression Surgery ◽

Optimal Care ◽

Epidural Steroid Injections ◽

Vascular Elements ◽

Evidenced Based ◽

Lumbar Spinal

Abstract Objective Lumbar spinal stenosis (LSS) can lead to compression of the neural and vascular elements and is becoming more common due to degenerative changes that occur because of aging processes. Symptoms may manifest as pain and discomfort that radiates to the lower leg, thigh, and/or buttocks. The traditional treatment algorithm for LSS consists of conservative management (physical therapy, medication, education, exercise), often followed by epidural steroid injections (ESIs), and when nonsurgical treatment has failed, open decompression surgery with or without fusion is considered. In this review, the variables that should be considered during the management of patients with LSS are discussed, and the role of each treatment option to provide optimal care is evaluated. Results This review leads to the creation of an evidence-based practical algorithm to aid clinicians in the management of patients with LSS. Special emphasis is directed at minimally invasive surgery, which should be taken into consideration when conservative management and ESI have failed.

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Inborn errors of thymic stromal cell development and function

Seminars in Immunopathology ◽

10.1007/s00281-020-00826-9 ◽

2020 ◽

Author(s):

Alexandra Y. Kreins ◽

Stefano Maio ◽

Fatima Dhalla

Keyword(s):

T Cell ◽

Stromal Cells ◽

Stromal Cell ◽

Cell Development ◽

Thymic Epithelial Cells ◽

Inborn Errors ◽

Vascular Elements ◽

Thymus Tissue ◽

Thymic Stromal Cells ◽

Thymic Stromal Cell

AbstractAs the primary site for T cell development, the thymus is responsible for the production and selection of a functional, yet self-tolerant T cell repertoire. This critically depends on thymic stromal cells, derived from the pharyngeal apparatus during embryogenesis. Thymic epithelial cells, mesenchymal and vascular elements together form the unique and highly specialised microenvironment required to support all aspects of thymopoiesis and T cell central tolerance induction. Although rare, inborn errors of thymic stromal cells constitute a clinically important group of conditions because their immunological consequences, which include autoimmune disease and T cell immunodeficiency, can be life-threatening if unrecognised and untreated. In this review, we describe the molecular and environmental aetiologies of the thymic stromal cell defects known to cause disease in humans, placing particular emphasis on those with a propensity to cause thymic hypoplasia or aplasia and consequently severe congenital immunodeficiency. We discuss the principles underpinning their diagnosis and management, including the use of novel tools to aid in their identification and strategies for curative treatment, principally transplantation of allogeneic thymus tissue.

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Survival strategies of Silene tatarica (Caryophyllaceae) in riparian and ruderal habitats

Canadian Journal of Botany ◽

10.1139/b04-014 ◽

2004 ◽

Vol 82 (4) ◽

pp. 491-502 ◽

Cited By ~ 8

Author(s):

Anne Jäkäläniemi ◽

Anneli Kauppi ◽

Antti Pramila ◽

Kalle Vähätaini

Keyword(s):

Ground Surface ◽

Survival Strategies ◽

Long Distance ◽

Anatomical Structures ◽

Riparian Plants ◽

Vascular Elements ◽

Flat Shape ◽

Habitat Properties ◽

Silene Tatarica ◽

Disturbed Habitats

Certain morphological and anatomical structures of riparian plants might be important for their survival during the season when they are exposed to severe stress caused by flooding, burial, fluctuating temperatures, and drought. These rare characteristics were studied as related to their ecological consequences in a threatened plant, Silene tatarica (L.) Pers., in riparian and ruderal habitats. The main differences between the habitats were morphological and closely related to the habitat properties, whereas the basic anatomy of structures was similar. After sand burial, most riparian plants formed vertical rhizomes and new meristems by bud ramification in the stem base near the ground surface. Special anatomical structures of fleshy underground stems and roots seem to allow plants to be resilient. Moreover, some primitive structures, such as vascular elements with helical and scalariform thickenings, collenchyma, and abundant xylem parenchyma, may increase the resilience of organs. High amounts of saccharose in fleshy rhizomes and roots can increase the cold resistance of plants. The flat shape and structures of tiny seeds may enhance the long-distance dispersal by water. We suggest that the synergism of these structures enables the survival of S. tatarica in highly disturbed habitats with fluctuating water levels.Key words: bud clusters, burial, flooding, growth habit, tensile strength, vertical rhizome.

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