Wound regeneration in the lamina of magnoliaceous leaves

1975 ◽  
Vol 53 (14) ◽  
pp. 1352-1364 ◽  
Author(s):  
Shirley C. Tucker
Keyword(s):  
Special Interest ◽  
Wound Repair ◽  
Healing Process ◽  
Guard Cells ◽  
Deciduous Species ◽  
Evergreen Species ◽  
Magnolia Grandiflora ◽  
Cell Divisions ◽  
Mature Leaves ◽  
Complete Process

Reparative tissue was observed around healed natural wounds in leaves of 53 species of 9 of the 12 magnoliaceous genera: Aromadendron, Elmerrillia, Kmeria, Liriodendron, Magnolia, Manglietia, Michelia, Paramichelia, and Talauma. Additional evidence was obtained from wounding experiments carried out on attached leaves of two evergreen species, Magnolia grandiflora and Michelia figo. Regeneration was studied over a 6-week period. Evergreen leaves produced more abundant regenerative tissues than deciduous leaves; a narrow-to-broad periderm forms consistently in all evergreen magnoliaceous leaves around wounds, but wounds in the deciduous species invoke little or no periderm development. The healing process in these leaves consists of three steps: (1) cells die along the wound, and cells immediately adjacent become physiologically altered; (2) a callus forms by randomly oriented cell divisions throughout mesophyll, vein sheath, and (in most species) epidermis; and (3) a periderm eventually forms in the band of callus parallel to the wound. The complete process takes 4 to 6 weeks in the evergreen magnoliaceous plants studied. The differences in healing processes are contrasted between evergreen and deciduous leaves. Of special interest is the observation that guard cells of mature leaves in several taxa dedifferentiate and undergo division in the area of wound repair.

Leaf nitrogen dynamics with particular reference to retranslocation in evergreen and deciduous tree species of Kumaun Himalaya

1993 ◽  
Vol 23 (3) ◽  
pp. 349-357 ◽  
Author(s):  
G.C.S. Negi ◽  
S.P. Singh
Keyword(s):  
Leaf Growth ◽  
Leaf Nitrogen ◽  
Deciduous Tree ◽  
Leaf Life Span ◽  
Deciduous Species ◽  
Evergreen Species ◽  
Mature Leaves ◽  
N Concentration ◽  
Leaf Formation ◽  
N Status

The concentration and mass of nitrogen (N) were followed seasonally in leaves of 26 trees species of Central Himalaya: 11 evergreen species with about 1-year leaf life-span and 15 deciduous species. Like the deciduous species, the leaves of these evergreen species start senescing and losing mass in the year of formation. Species with higher N status retranslocated a larger proportion of leaf N prior to leaf abscission than the species with less favourable N status. The percentage of N mass in the leaf that was retranslocated during senescence ranged from 32.7 to 75.3%, but none of the species with N concentration less than 2.5% in mature leaves retranslocated more than 60% of N. Compared with evergreen species, on average the deciduous species showed higher N concentration in mature leaves (3.2 vs. 2.5%), higher proportion of leaf mass loss during senescence (31.6 vs. 26.2%), and greater proportion of retranslocated N mass from leaves (57.1 vs. 51.8%). With regard to the N-use efficiency the two groups of species were not clearly different. The dependence of deciduous species on retranslocated N mass for leaf growth during the dry period of the premonsoon season was greater than that of the evergreen species, which showed partial dependence on the soil N pool for new leaf formation.

scholarly journals The Role of the Extracellular Matrix Components in Cutaneous Wound Healing

2014 ◽  
Vol 2014 ◽  
pp. 1-8 ◽  
Author(s):  
Pawel Olczyk ◽  
Łukasz Mencner ◽  
Katarzyna Komosinska-Vassev
Keyword(s):  
Extracellular Matrix ◽  
Wound Healing ◽  
Growth Factors ◽  
Wound Repair ◽  
Structural Integrity ◽  
Healing Process ◽  
Cellular Functions ◽  
Extracellular Matrix Components ◽  
Essential Components ◽  
Matrix Components

Wound healing is the physiologic response to tissue trauma proceeding as a complex pathway of biochemical reactions and cellular events, secreted growth factors, and cytokines. Extracellular matrix constituents are essential components of the wound repair phenomenon. Firstly, they create a provisional matrix, providing a structural integrity of matrix during each stage of healing process. Secondly, matrix molecules regulate cellular functions, mediate the cell-cell and cell-matrix interactions, and serve as a reservoir and modulator of cytokines and growth factors’ action. Currently known mechanisms, by which extracellular matrix components modulate each stage of the process of soft tissue remodeling after injury, have been discussed.

Differential impact of liana colonization on the leaf functional traits of co-occurring deciduous and evergreen trees

2021 ◽  
Author(s):  
vivek pandi ◽  
Kanda Naveen Babu
Keyword(s):  
Functional Traits ◽  
Tree Species ◽  
Dry Matter Content ◽  
Differential Impact ◽  
Deciduous Species ◽  
Evergreen Species ◽  
Leaf Functional Traits ◽  
Leaf Trait ◽  
Host Trees ◽  
Significant Difference

Abstract The present study was carried out to analyse the leaf functional traits of co-occurring evergreen and deciduous tree species in a tropical dry scrub forest. This study also intended to check whether the species with contrasting leaf habits differ in their leaf trait plasticity, responding to the canopy-infestation by lianas. A total of 12 leaf functional traits were studied for eight tree species with contrasting leaf habits (evergreen and deciduous) and liana-colonization status (Liana+ and Liana−). In the liana-free environment (L−), evergreen trees had significantly higher specific leaf mass (LMA) and leaf dry matter content (LDMC) than the deciduous species. Whereas, the deciduous trees had higher specific leaf area (SLA) and mass-based leaf nitrogen concentration (Nmass). The leaf trait-pair relationship in the present study agreed to the well-established global trait-pair relationships (SLA Vs Nmass, Lth Vs SLA, Nmass Vs Lth, Nmass Vs LDMC, LDMC Vs SLA). There was no significant difference between L+ and L− individuals in any leaf functional traits studied in the deciduous species. However, evergreen species showed marked differences in the total chlorophyll content (Chlt), chlorophyll b (Chlb), SLA, and LMA between L+ and L− individuals of the same species. Deciduous species with the acquisitive strategy can have a competitive advantage over evergreen species in the exposed environment (L−) whereas, evergreen species with shade-tolerant properties were better acclimated to the shaded environments (L+). The result revealed the patterns of convergence and divergence in some of the leaf functional traits between evergreen and deciduous species. The results also showed the differential impact of liana colonization on the host trees with contrasting leaf habits. Therefore, liana colonization can significantly impact the C-fixation strategies of the host trees by altering their light environment. Further, the magnitude of such impact may vary among species of different leaf habits. The increased proliferation of lianas in the tropical forest canopies may pose a severe threat to the whole forest carbon assimilation rates.

Architectural differences in saplings of temperate versus tropical angiosperms; consequences of the deciduous habit?

2005 ◽  
Vol 83 (11) ◽  
pp. 1391-1401 ◽  
Author(s):  
David A. King
Keyword(s):  
High Frequency ◽  
Plant Architecture ◽  
Tropical Species ◽  
Deciduous Species ◽  
Evergreen Species ◽  
Crown Shape ◽  
Temperate Deciduous ◽  
Lower Height ◽  
Filtering Effect ◽  
Overstory Trees

The architecture of saplings of temperate deciduous species of the southeastern United States was compared with that of tropical evergreen species of Central America, Borneo, and northeastern Australia. The deciduous species were more planar in the understory than were the tropical species, because of (i) more planar leaf displays within branches, (ii) a high frequency of arching, plagiotropic main stems (associated with greater plasticity in crown symmetry in relation to light), and (iii) a lower height of first branching. The deciduous species also had more planar branches than did subtropical and temperate evergreen angiosperms. This greater planarity in temperate deciduous understories may be associated with the simultaneous positioning of most leaves during a single flush in the spring. In contrast, saplings in tropical understories typically bear multiple leaf cohorts and position new leaves at the peripheries of existing leaf displays. These results and those of other studies suggest that there are adaptive links between plant architecture and phenology. Other factors, such as latitudinal variation in sun angles, may influence crown shape in overstory trees, but did not seem to be involved here, possibly because the filtering effect of the canopy results in smaller latitudinal shifts in understory illumination angles during the growing season. Thus, by favouring the deciduous habit, the cold winters and warm, humid summers of the eastern deciduous biome of North America appear to have had a notable influence on sapling architecture.

scholarly journals Topical Saudi Arabia Talh honey (Acacia nilotica) on surgical wound healing activity

2020 ◽  
Author(s):  
Ahmed G. Hegazi ◽  
Faiz M. Al Guthami ◽  
Mohamed H. Basiouny ◽  
Ahmed F.M. Al Gethami
Keyword(s):  
Wound Healing ◽  
Saudi Arabia ◽  
Wound Repair ◽  
Healing Process ◽  
Bacterial Count ◽  
Tissue Growth ◽  
Acacia Nilotica ◽  
Total Bacterial Count ◽  
Wound Healing Process ◽  
Ifn Γ

Honey has been documented as the oldest traditional medicine. It has been effective in suppressing inflammation, wound repair enhancer, and rapid autolytic debridement. The aim of this investigation was to evaluate the role of Saudi Arabia Talh honey (Acacia nilotica) dressing as a good alternative in care of diabetic foot (DFU) healing activity for twenty patients, wound total bacterial count, and serum cytokines levels (IFN-γ, IL-1, and IL-6). The results showed that Talh honey stimulates the wound healing process, broad-spectrum antibacterial activity, and reduction in the proinflammatory cytokines IFN-γ, IL-1, and IL-6 levels. It could be concluded that Talh honey bioactivities enhance wound healing by promoting tissue growth leading to wound repair, antibacterial, and reduction of inflammation.

scholarly journals Systemic and topical administration of spermidine accelerates skin wound healing

2020 ◽  
Author(s):  
Daisuke Ito ◽  
Hiroyasu Ito ◽  
Takayasu Ideta ◽  
Ayumu Kanbe ◽  
Soranobu Ninomiya ◽  
...  
Keyword(s):  
Cell Proliferation ◽  
Wound Healing ◽  
Wound Repair ◽  
Healing Process ◽  
Topical Administration ◽  
Skin Wound ◽  
Wound Healing Process ◽  
Skin Wound Healing

Abstract Background The skin wound healing process is regulated by various cytokines, chemokines, and growth factors. Recent reports have demonstrated that spermine/spermidine (SPD) promote wound healing through urokinase-type plasminogen activator (uPA)/uPA receptor (uPAR) signaling in vitro. Here, we investigated whether the systemic and topical administration of SPD would accelerate the skin wound-repair process in vivo.Methods A skin wound repair model was established using C57BL/6 J mice. SPD was mixed with white petrolatum for topical administration. For systemic administration, SPD mixed with drinking water was orally administered. Changes in wound size over time were calculated using digital photography.Results Systemic and topical SPD treatment significantly accelerated skin wound healing. The administration of SPD promoted the uPA/uPAR pathway in wound sites. Moreover, topical treatment with SPD enhanced the expression of IL-6 and TNF-α in wound sites. Scratch and cell proliferation assays revealed that SPD administration accelerated scratch wound closure and cell proliferation in vitro.Conclusion These results indicate that treatment with SPD promotes skin wound healing through activation of the uPA/uPAR pathway and induction of the inflammatory response in wound sites. The administration of SPD might contribute to new effective treatments to accelerate skin wound healing.

scholarly journals Susceptibility of Viburnum Species and Cultivars to Phytophthora ramorum

2010 ◽  
Vol 28 (4) ◽  
pp. 197-202 ◽  
Author(s):  
Timothy L. Widmer
Keyword(s):  
Leaf Area ◽  
Phytophthora Ramorum ◽  
Necrotic Area ◽  
Deciduous Species ◽  
Evergreen Species ◽  
Whole Plants

Abstract Phytophthora ramorum causes ramorum blight on Viburnum species, which are commonly grown as ornamentals. This study evaluated 24 different species or cultivars for susceptibility to P. ramorum. Whole plants were inoculated with an NA1 isolate of P. ramorum and placed in dew chambers at 20C (68F). After 5 days, the percentage of necrotic leaves for each plant and the percentage of necrotic area for each leaf were calculated. The percentage of necrotic leaves per plant ranged from 96.1% (V. tinus) to 7.9% (V. opulus ‘Notcutt’) and the percentage of necrotic leaf area ranged from 73.0% (V. × carlcephalum ‘Cayuga’) to 2.4% (V. trilobum ‘Wentworth’). In addition, six species or cultivars were evaluated for their susceptibility to a EU1 isolate of P. ramorum. The isolate had a significant effect on three of the six species or cultivars tested, although one isolate did not always yield the greatest necrosis. Evergreen species and cultivars had a higher percentage of necrotic leaves and higher percentage of necrotic leaf area than semi-evergreen or deciduous species and cultivars. All Viburnum species and cultivars showed some degree of susceptibility to P ramorum.

scholarly journals Human Gingival Fibroblasts Exposed to Extremely Low-Frequency Electromagnetic Fields: In Vitro Model of Wound-Healing Improvement

2019 ◽  
Vol 20 (9) ◽  
pp. 2108 ◽  
Author(s):  
Erica Costantini ◽  
Bruna Sinjari ◽  
Chiara D’Angelo ◽  
Giovanna Murmura ◽  
Marcella Reale ◽  
...  
Keyword(s):  
Wound Healing ◽  
Electromagnetic Field ◽  
Electromagnetic Fields ◽  
Wound Repair ◽  
Healing Process ◽  
Low Frequency ◽  
Gingival Fibroblasts ◽  
Field Exposure ◽  
Extremely Low Frequency

Several clinical studies have suggested the impact of sinusoidal and pulsed electromagnetic fields in quickening wound repair processes and tissue regeneration. The clinical use of extremely low-frequency electromagnetic fields could represent a novel frontier in tissue repair and oral health, with an interesting clinical perspective. The present study aimed to evaluate the effect of an extremely low-frequency sinusoidal electromagnetic field (SEMF) and an extremely low-frequency pulsed electromagnetic field (PEMF) with flux densities of 1 mT on a model of oral healing process using gingival fibroblasts. An in vitro mechanical injury was produced to evaluate wound healing, migration, viability, metabolism, and the expression of selected cytokines and protease genes in fibroblasts exposed to or not exposed to the SEMF and the PEMF. Interleukin 6 (IL-6), transforming growth factor beta 1 (TGF-β), metalloproteinase 2 (MMP-2), monocyte chemoattractant protein 1 (MCP-1), inducible nitric oxide synthase (iNOS), and heme oxygenase 1 (HO-1) are involved in wound healing and tissue regeneration, favoring fibroblast proliferation, chemotaxis, and activation. Our results show that the exposure to each type of electromagnetic field increases the early expression of IL-6, TGF-β, and iNOS, driving a shift from an inflammatory to a proliferative phase of wound repair. Additionally, a later induction of MMP-2, MCP-1, and HO-1 was observed after electromagnetic field exposure, which quickened the wound-healing process. Moreover, electromagnetic field exposure influenced the proliferation, migration, and metabolism of human gingival fibroblasts compared to sham-exposed cells. This study suggests that exposure to SEMF and PEMF could be an interesting new non-invasive treatment option for wound healing. However, additional studies are needed to elucidate the best exposure conditions to provide the desired in vivo treatment efficacy.

scholarly journals Phenology and water relations of eight woody species in the Coronation Garden of Kirtipur, central Nepal

1970 ◽  
Vol 4 (6) ◽  
pp. 49-56
Author(s):  
Bharat B Shrestha ◽  
Yadav Uprety ◽  
Keshav Nepal ◽  
Sandhya Tripathi ◽  
Pramod K Jha
Keyword(s):  
Woody Species ◽  
Dry Season ◽  
Elastic Tissue ◽  
Deciduous Species ◽  
Evergreen Species ◽  
Central Nepal ◽  
Relative Water ◽  
Bauhinia Variegata ◽  
Celtis Australis ◽  
Woodfordia Fruticosa

Phenological activities of eight woody species planted in Kirtipur (central Nepal) were examined, each for one dry season between September 2001 and June 2003. From Pressure Volume (P-V) analysis, we determined relative water content at zero turgor (RWCz), osmotic potential at zero turgor (Ψsz) and full turgor (Ψsf ), and bulk modulus of elasticity (ε) once a month through the course of dry season. Both evergreen species (Cotoneaster bacillaris Wall., Quercus lanata Sm., Ligustrum confusum Decne., Woodfordia fruticosa (L.) Kurz.) and deciduous species (Celtis australis Linn., Alnus nepalensis D.Don., Bauhinia variegata Linn. and Lagerstroemia indica Linn.) put out their new leaves during the dry summer when day length and temperature were increasing. Generally, bud break coincided with concentrated leaf fall during the dry summer and the leaf fall reduced total leaf area to its lowest value. The deciduous species were leafless for one to three months, followed by a prolonged period of leaf production and shoot elongation. Evergreen and deciduous species manifested distinct adaptive strategies to water deficit. Evergreens can reduce osmotic potential (Ψs) to its low value and maintain proper water potential (Ψ) gradient from soil to plant, which facilitates absorption of water during dry season. Elastic tissue in deciduous species is coupled with leaf shedding during the dry season; both factors may help maintain proper Ψs for new growth during dry period. One evergreen species (Woodfordia fruticosa) and three deciduous species (Celtis australis, Bauhinia variegata and Lagerstroemia indica) have inherently high dehydration tolerance due to their elastic tissue. During drought there has been osmotic adjustment in Quercus lanata, and elastic adjustment in Ligustrum confusum, Celtis australis and Lagerstroemia indica. Key words: Himalayas, Pressure Volume (P-V) curve, relative water content (RWC), osmotic adjustment, elastic adjustment Himalayan Journal of Sciences Vol.4(6) 2007 p.49-56

scholarly journals Endothelial Response Boosted by Platelet Lysate: The Involvement of Calcium Toolkit

2020 ◽  
Vol 21 (3) ◽  
pp. 808
Author(s):  
Simona Martinotti ◽  
Mauro Patrone ◽  
Valeria Balbo ◽  
Laura Mazzucco ◽  
Elia Ranzato
Keyword(s):  
Growth Factors ◽  
Endothelial Cell ◽  
Wound Repair ◽  
Cell Model ◽  
Healing Process ◽  
Platelet Lysate ◽  
Bioactive Molecules ◽  
Freezing And Thawing ◽  
Blood Samples ◽  
Nadph Oxidase 4

Wound repair is a dynamic process during which crucial signaling pathways are regulated by growth factors and cytokines released by several kinds of cells directly involved in the healing process. However, the limited applications and heterogeneous clinical results of single growth factors in wound healing encouraged the use of a mixture of bioactive molecules such as platelet derivatives for best results in wound repair. An interesting platelet derivative, obtained from blood samples, is platelet lysate (PL), which has shown potential clinical application. PL is obtained from freezing and thawing of platelet-enriched blood samples. Intracellular calcium (Ca2+) signals play a central role in the control of endothelial cell survival, proliferation, motility, and differentiation. We investigated the role of Ca2+ signaling in the PL-driven endothelial healing process. In our experiments, the functional significance of Ca2+ signaling machinery was highlighted performing the scratch wound assay in presence of different inhibitors or specific RNAi. We also pointed out that the PL-induced generation of intracellular ROS (reactive oxygen species) via NOX4 (NADPH oxidase 4) is necessary for the activation of TRPM2 and the resulting Ca2+ entry from the extracellular space. This is the first report of the mechanism of wound repair in an endothelial cell model boosted by the PL-induced regulation of [Ca2+]i.

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