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21.
Aboveground disturbances are common in dynamic riparian environments, and Salix nigra is well adapted with a vigorous resprouting response. Soil moisture stresses are also common, and S. nigra is flood tolerant and drought sensitive. The objective of this study was to quantify nonstructural carbohydrate (NSC) reserves
in S. nigra following shoot removal and soil moisture treatments. NSC reserves provide energy for regeneration of shoot tissue until
new functional leaves are developed. Three soil moisture treatments: well-watered (W), periodic flooding (F) and drought (D);
and three shoot removal treatments: no shoots removed (R0), partial shoot removal (R1), and complete shoot removal (R2) were
applied. Plants were harvested when new shoot development was observed (day 13). Statistical significance in the 3 × 3-factorial
design was determined in two-factor ANOVA at P < 0.05. Both roots and cuttings were important reservoirs for NSC during resprouting response, with decreases in root (31%)
and cutting (14%) biomass in R2 compared to R0. Rapid recovery of photosynthetic surface area (from 15 to 37% of R0) was found
in R1. A clear pattern of starch mobilization was found in roots in R0, R1 and R2, with lowest root starch concentration in
W, F higher than W, and D higher than F. Shoot starch concentration was lower in F and D compared to W in R0, however, in
R1 shoot starch was reduced in W compared to F and D, possibly indicating reduced rates of translocation during soil moisture
stress. Evidence of osmotic adjustment was found in roots and shoots with higher total ethanol-soluble carbohydrates (TESC)
during soil moisture stress in F and D treatments. Total plant NSC pool was greater in F and D treatments compared to W, and
progressively reduced from R0 to R1 to R2. Results indicated negative effects of drought, and to a lesser extent periodic
flooding on resprouting response in S. nigra, with implications for reduced survival when exposed to combined stresses of aboveground disturbance and soil moisture. 相似文献
22.
Photosynthesis and root growth in Spartina alterniflora in relation to root zone aeration 总被引:1,自引:0,他引:1
S.R. Pezeshki 《Photosynthetica》1997,34(1):107-114
Spartina alterniflora Lois. is a dominant species growing in intermediate and saline marshes of the US Gulf coast and Atlantic
coastal marshes. S. alterniflora plants were subjected to a range of soil redox potential (Eh) conditions representing a well
aerated to reduced conditions in a rhizotron system under controlled environmental conditions. The low soil Eh resulted in
inhibition of root elongation shortly after treatment initiation. Root elongation was reduced as soil Eh approached values
below ca. +350 mV. Substantial decrease in root elongation was noted when soil Eh fell below +200 mV. Generally, net photosynthetic
rate (PN) decreased as soil Eh was reduced, with substantial reductions in PN found when Eh approached negative values. Average
PN was reduced to 87, 64, and 44% of control under +340, +245, and -180 mV treatments, respectively. The reductions in root
elongation and PN in response to low soil Eh indicated the adverse effects of low soil Eh on plant functioning and the need
for periods of soil aeration that allow plants to resume normal functioning. Thus periods of drainage allowing soil aeration
during the growing season appear to be critical to S. alterniflora by providing favorable conditions for root growth and gas
exchange with important implications for plant carbon fixation.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
23.
Jafar Rezaie Reza Rahbarghazi Milad Pezeshki Mahdi Mazhar Farshid Yekani Majid Khaksar Elhameh Shokrollahi Hassan Amini Shahriar Hashemzadeh Sadiye Emel Sokullu Mehmet Tokac 《Journal of cellular physiology》2019,234(12):21732-21745
Extracellular vesicles (EVs) are nano-sized vesicles, released from many cell types including cardiac cells, have recently emerged as intercellular communication tools in cell dynamics. EVs are an important mediator of signaling within cells that influencing the functional behavior of the target cells. In heart complex, cardiac cells can easily use EVs to transport bioactive molecules such as proteins, lipids, and RNAs to the regulation of neighboring cell function. Cross-talk between intracardiac cells plays pivotal roles in the heart homeostasis and in adaptive responses of the heart to stress. EVs were released by cardiomyocytes under baseline conditions, but stress condition such as hypoxia intensifies secretome capacity. EVs secreted by cardiac progenitor cells and cardiosphere-derived cells could be pinpointed as important mediators of cardioprotection and cardiogenesis. Furthermore, EVs from many different types of stem cells could potentially exert a therapeutic effect on the damaged heart. Recent evidence shows that cardiac-derived EVs are rich in microRNAs, suggesting a key role in the controlling of cellular processes. EVs harboring exosomes may be clinically useful in cell-free therapy approaches and potentially act as prognosis and diagnosis biomarkers of cardiovascular diseases. 相似文献
24.
25.
Mohsen Hesami Mohammad Hosein Daneshvar Mohsen Yoosefzadeh-Najafabadi Milad Alizadeh 《Journal of Genetic Engineering and Biotechnology》2018,16(1):175-180
Ficus religiosa is known as a long-lived multipurpose forest tree. The tree plays an important role for religious, medicinal, and ornamental purposes. However, the propagation rate of Ficus religiosa is low in natural habitat so the plant tissue culture techniques are an applicable method for multiplication of this valuable medicinal plants. Thus, the aim of this study is to understand the effect of different auxin/cytokinin ratios on indirect shoot organogenesis of this plant. According to our results, the maximum callus induction frequency (100%) was obtained on Murashige and Skoog (MS) medium supplemented with 0.5?mg/l 2,4-dichlorophenoxyacetic acid (2,4-D) plus 0.05?mg/l 6-benzylaminopurine (BAP) from petiole segments. For shoot induction purpose, the yellow-brownish, friable, organogenic calli were inoculated on shoot induction medium. On MS medium supplemented with 1.5?mg/l BAP and 0.15?mg/l Indole-3-butyric acid (IBA), 96.66% of the petiole-derived calli responded with an average number of 3.56 shoots per culture. The highest root formation frequency (96.66%), root number (5.5), and root length (4.83?cm) were achieved on MS medium containing 2.0?mg/l IBA plus 0.1?mg/l Naphthaleneacetic acid (NAA). The rooted shoots were successfully transferred to field condition and the substrate with the mixture of cocopeat and perlite (1:1) had the highest survival rate (96.66%). This is the first report of an effective in vitro organogenesis protocol for F. religiosa by indirect shoot organogenesis through axenic seedling derived petiole explants, which can be efficiently employed for conservation of this important medicinal plant species as well as the utilization of active biomolecules. 相似文献
26.
Milad Ghasemi David R. Nolan Caitríona Lally 《Biomechanics and modeling in mechanobiology》2018,17(6):1757-1769
Carotid atherosclerotic plaque rupture is one of the leading causes of stroke. Treatments for atherosclerosis can induce tissue damage during the deployment of an intravascular device or through external tissue clamping during surgery. In this paper, a constituent specific study was performed to investigate the role of the ground matrix and collagen fibres of arterial tissue in response to supra-physiological loads. Cyclic mechanical tests were conducted on intact and collagenase-digested strips of porcine common carotid arteries. Using these tests, four passive damage-relevant phenomena were studied, namely (i) Mullins effect, (ii) hysteresis, (iii) permanent set and (iv) matrix failure and fibre rupture. A constitutive model was also developed to capture all of these damage-relevant phenomena using a continuum damage mechanics approach. The implemented constitutive model was fit to experimental results for both intact and digested samples. The results of this work demonstrate the important role of the ground matrix in the permanent deformation of the arterial tissue under high loads. Supra-physiological load-induced tissue damage may play a key role in vascular remodelling in arteries with atherosclerosis or following interventional procedures. 相似文献
27.
Mona Navaei-Nigjeh Milad Moloudizargari Maryam Baeeri Mahdi Gholami Nasrin Lotfibakhshaiesh Masoud Soleimani Ebrahim Vasheghani-farahani Jafar AI Mohammad Abdollahi 《Cytotherapy》2018,20(9):1124-1142
Background aims
Adipose tissue–derived mesenchymal stromal cells (AT-MSCs), widely known as multipotent progenitors, release several cytokines that support cell survival and repair. There are in vitro and in vivo studies reporting the regenerative role of AT-MSCs possibly mediated by their protective effects on functional islet cells as well as their capacity to differentiate into insulin-producing cells (IPCs).Methods
On such a basis, our goal in the present study was to use three different models including direct and indirect co-cultures and islet-derived conditioned medium (CM) to differentiate AT-MSCs into IPCs and to illuminate the molecular mechanisms of the beneficial impact of AT-MSCs on pancreatic islet functionality. Furthermore, we combined in vitro co-culture of islets and AT-MSCs with in vivo assessment of islet graft function to assess whether co-transplantation of islets with AT-MSCs can reduce marginal mass required for successful islet transplantation and prolong graft function in a diabetic rat model.Results
Our findings demonstrated that AT-MSCs are suitable for creating a microenvironment favorable for the repair and longevity of the pancreas β cells through the improvement of islet survival and maintenance of cell morphology and insulin secretion due to their potent properties in differentiation. Most importantly, hybrid transplantation of islets with AT-MSCs significantly promoted survival, engraftment and insulin-producing function of the graft and reduced the islet mass required for reversal of diabetes.Conclusions
This strategy might be of therapeutic potential solving the problem of donor islet material loss that currently limits the application of allogeneic islet transplantation as a more widespread therapy for type 1 diabetes. 相似文献28.
Wallinder C Botros M Rosenström U Guimond MO Beaudry H Nyberg F Gallo-Payet N Hallberg A Alterman M 《Bioorganic & medicinal chemistry》2008,16(14):6841-6849
In the investigation of the structure-activity relationship of nonpeptide AT(2) receptor agonists, a series of substituted benzamide analogues of the selective nonpeptide AT(2) receptor agonist M024 have been synthesised. In a second series, the biphenyl scaffold was compared to the thienylphenyl scaffold and the impact of the isobutyl substituent and its position on AT(1)/AT(2) receptor selectivity was also investigated. Both series included several compounds with high affinity and selectivity for the AT(2) receptor. Three of the compounds were also proven to function as agonists at the AT(2) receptor, as deduced from a neurite outgrowth assay, conducted in NG108-15 cells. 相似文献
29.
Shaghayegh Pezeshki Payam Hashemi Alireza Salimi Sheida Ebrahimi Mandana Javanzad Amir Monfaredan 《Reports of Biochemistry & Molecular Biology》2021,10(2):224
Background:Prostate cancer (PC) is one of the most abundant cancers among men, and In Iran, has been responsible for 6% of all deaths from cancer in men. NUF2 and GMNN genes are considered as loci of susceptibility to tumorigenesis in humans. Alterations in expression of these genes have been reported in various malignancies. The aim of our study was to test whether different NUF2 and GMNN expression levels are associated with PC incidence and hence, might be considered as new molecular tools for PC screening.Methods:Biopsy samples from 40 PC patients and 41 healthy Iranian men were used to determine the relative gene expression. After RNA extraction and cDNA synthesis, samples were analyzed using TaqMan Quantitative Real time PCR. Patients’ background information, included smoking habits and family histories of PC, were recorded. Stages and grades of their PC were classified by the TNM tumor, node, metastasis (TMN) staging system based on standard guidelines.Results:NUF2 expression did not significantly differ between the groups, while GMNN expression was significantly greater in the PC specimens than in the controls.Conclusion:Regarding the significant role of GMNN in various tumor phenotypes, and its importance in PC progression, the alteration in GMNN expression in PC samples vs. controls indicate that the genetic profiling of this cancer might be considered to personalize therapy for each patient in the future.Key Words: Family history, Geminin (GMNN), Tumor staging, NUF2, Prostate cancer 相似文献
30.
Milad Aeini 《Archives Of Phytopathology And Plant Protection》2013,46(12):1466-1474
Chinaberry (Melia azedarach) is a deciduous tree of moderate size, grown throughout warm countries. The plantation of M. azedarach tree improves the environmental condition of the country. During the years 1390–1391, bacterial gall symptoms were observed on chinaberry. The isolation of the causal agent bacteria was done on nutrient agar medium. Approximately 4 weeks after inoculation, galls developed on the chinaberries inoculated with different isolates. The specific primer was designed based on 16S rRNA gene and all isolates amplified 429 bp fragment. To sequence 16S rRNA gene of Shiraz isolates, the universal primer PS16Sf-FAM/PS23Sr was used to amplify 16S rRNA gene. The Iranian isolates of Pseudomonas meliae showed 99.7% similarity to P. meliae (type strain) in the Gene Bank. Based on the rep-PCR results and sequence of 16S rRNA gene, Pseudomonas syringae and Pseudomonas fluorescens were placed in the different groups. 相似文献