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191.
  • Climate change is increasing the frequency of extreme events such as droughts, limiting plant growth and productivity. Exogenous application of plant growth regulators, such as 24-epibrassinolide (EBR), might be a solution as this molecule is organic, eco-friendly, and biodegradable. This is the first research to examine possible roles of EBR on the hydraulic safety margin, physiological behaviour, and metabolism in Carapa guianensis Aubl. (Meliaceae) exposed to drought. C. guianensis is a widely distributed tree in tropical forests of the Amazon.
  • The objective was to determine whether EBR can improve tolerance to water deficit in young C. guianensis by measuring hydraulic traits, nutritional, biochemical and physiological responses, and biomass. The experiment had four randomized treatments: two water conditions (control and water deficit) and two concentrations of EBR (0 and 100 nM EBR).
  • EBR increased the water potential and hydraulic safety margin, increased CO2 fixation, and improved stomatal performance. EBR also stimulated antioxidant defences (SOD, CAT, APX, and POX).
  • Overall, tretreatment with EBR improved drought tolerance of young C. guianensis plants.
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192.
The many clinical trials currently in progress will likely lead to the widespread use of stem cell-based therapies for an extensive variety of diseases, either in autologous or allogeneic settings. With the current pace of progress, in a few years' time, the field of stem cell-based therapy should be able to respond to the market demand for safe, robust and clinically efficient stem cell-based therapeutics. Due to the limited number of stem cells that can be obtained from a single donor, one of the major challenges on the roadmap for regulatory approval of such medicinal products is the expansion of stem cells using Good Manufacturing Practices (GMP)-compliant culture systems. In fact, manufacturing costs, which include production and quality control procedures, may be the main hurdle for developing cost-effective stem cell therapies. Bioreactors provide a viable alternative to the traditional static culture systems in that bioreactors provide the required scalability, incorporate monitoring and control tools, and possess the operational flexibility to be adapted to the differing requirements imposed by various clinical applications. Bioreactor systems face a number of issues when incorporated into stem cell expansion protocols, both during development at the research level and when bioreactors are used in on-going clinical trials. This review provides an overview of the issues that must be confronted during the development of GMP-compliant bioreactors systems used to support the various clinical applications employing stem cells.  相似文献   
193.
The length-weight relationship is important for the study of populational dynamics. This study aimed to describe the length-weight relationships (LWR) of 11 fish species sampled on 18 streams of the Capim river basin on eastern Amazon. Specimens were captured in 2014, 2015 and 2017, using sieve nets with 2 mm of mesh size. Fixed specimens were fixed in 10% formalin and conserved in alcohol 70%, measured for standard length (SL, 0.1 cm) and total weight (W, 0.01 g). The 11 species analysed were: Hemigrammus bellottii, Hemigrammus ocellifer, Hyphessobrycon heterorhabdus, Iguanodectes rachovii, Copella arnoldi, Nannostomus trifasciatus, Apistogramma regani, Apistogramma agassizii, Gymnorhamphichthys rondoni, Hypopygus lepturus, Anablepsoides urophthalmus.  相似文献   
194.
In the present study, the frequency, the activation and the cytokine and chemokine profile of HTLV-1 carriers with or without dermatological lesions were thoroughly described and compared. The results indicated that HTLV-1-infected patients with dermatological lesions have distinct frequency and activation status when compared to asymptomatic carriers. Alterations in the CD4+HLA-DR+, CD8+ T cell, macrophage-like and NKT subsets as well as in the serum chemokines CCL5, CXCL8, CXCL9 and CXCL10 were observed in the HTLV-1-infected group with skin lesions. Additionally, HTLV-1 carriers with dermatological skin lesions showed more frequently high proviral load as compared to asymptomatic carriers. The elevated proviral load in HTLV-1 patients with infectious skin lesions correlated significantly with TNF-α/IL-10 ratio, while the same significant correlation was found for the IL-12/IL-10 ratio and the high proviral load in HTLV-1-infected patients with autoimmune skin lesions. All in all, these results suggest a distinct and unique immunological profile in the peripheral blood of HTLV-1-infected patients with skin disorders, and the different nature of skin lesion observed in these patients may be an outcome of a distinct unbalance of the systemic inflammatory response upon HTLV-1 infection.  相似文献   
195.
Stress ulcers are characterized by difficult management and poor prognosis. They currently represent a complication in the clinical course of other conditions, mainly shock states. The pathogenesis of stress ulcers is not well understood although the role of hypovolemia leading to energetic deprivation and insaturation of anaerobic cellular metabolism have been carefully studied. Somatostatin has been found to reduce the incidence of experimental stress ulcers. In the clinic, patients with duodenal ulcers were found to exhibit a low number of antral D cells and a significant decrease in tissue somatostatin. In a multicenter trial, patients with bleeding peptic or stress ulcers were treated with somatostatin or cimetidine plus pirenzepine. Results were favorable to the former substance on account of the time required to stop the hemorrhage and the demands for blood replacement. Thus, medical management of bleeding ulcers with somatostatin may represent an alternative to more radical surgical intervention.  相似文献   
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197.

Adverse effects caused by inadequate magnesium (Mg) supply (deficiency or excess) often cause oxidative stress in chloroplasts and a decline in photosynthetic activity. However, 24-epibrassinolide (EBR) is a natural, biodegradable, and ecologically viable plant growth regulator with multiple roles in plant metabolism. This research aims to determine whether the foliar application of EBR (1) can delay chlorophyll degradation and/or (2) mitigate oxidative stress on the photosynthetic process in magnesium-stressed soybean plants. The experiment followed a completely randomized factorial design with two concentrations of 24-epibrassinolide (0 and 0.1 mM EBR, described as – EBR and?+?EBR, respectively) and three Mg supplies (0.0225, 2.25 and 225 mM Mg, described as low, control and high supply of Mg). Inadequate Mg supplies (deficiency and excess) negatively interfered with photosynthetic pigments, chlorophyll fluorescence and gas exchange. However, exogenous EBR sprayed in plants under high Mg maximized superoxide dismutase (37%), catalase (34%), ascorbate peroxidase (48%) and peroxidase (49%), protecting against oxidative stress and delaying chlorophyll degradation. Concomitantly, plants sprayed with this steroid had increases in Mg content, improving the photochemical efficiency and gas exchange because Mg plays an essential role during the light capture process.

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