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91.
Amin Soltangheisi Paul J. A. Withers Paulo Sergio Pavinato Maurício Roberto Cherubin Raffaella Rossetto Janaina Braga Do Carmo Gustavo Casoni da Rocha Luiz Antonio Martinelli 《Global Change Biology Bioenergy》2019,11(12):1444-1455
Phosphorus (P) use in global food and bioenergy production needs to become more efficient and sustainable to reduce environmental impacts and conserve a finite and critical resource (Carpenter & Bennett, Environmental Research Letters, 2011, 6, 014009; Springmann et al., Nature, 2018, 562, 519). Sugarcane is one crop with a large P footprint because production is centered on P‐fixing soils with low P availability (Roy et al., Nature Plants, 2016, 2, 16043; Withers et al., Scientific Reports, 2018, 8, 2537). As global demand for processed sugar and bioethanol continues to increase, we advocate that improving P efficiency could become a key sustainability goal for the sugarcane industry. Here, we applied the 5R global P stewardship framework (Withers et al., Ambio, 2015, 44, 193) to identify more sustainable options to manage P in Brazilian sugarcane production. We show that current inputs of P fertilizer to the current crop area could be reduced by over 305 Gg, or 63%, over the next three decades by reducing unnecessary P fertilizer use, better utilization of recyclable bioresources and redesigning recommendation systems. Adoption of these 5R options would save the sugarcane industry in Brazil 528 US$ million and help safeguard global food and energy security. 相似文献
92.
Dhimant Desai Matthew Lauver Alexandria Ostman Linda Cruz Kevin Ferguson Ge Jin Brianne Roper Daniel Brosius Aron Lukacher Shantu Amin Nick Buchkovich 《Bioorganic & medicinal chemistry》2019,27(9):1795-1803
Opportunistic viruses are a major problem for immunosuppressed individuals, particularly following organ or stem cell transplantation. Current treatments are non-existent or suffer from problems such as high toxicity or development of resistant strains. We previously published that a trafficking inhibitor that targets a host protein greatly reduces the replication of human cytomegalovirus. This inhibitor was also shown to be moderately effective against polyomaviruses, another family of opportunistic viruses. We have developed a panel of analogues for this inhibitor and have shown that these analogues maintain their high efficacy against HCMV, while substantially lowering the concentration required to inhibit polyomavirus replication. By targeting a host protein these compounds are able to inhibit the replication of two very different viruses. These observations open up the possibility of pan-viral inhibitors for immunosuppressed individuals that are effective against multiple, diverse opportunistic viruses. 相似文献
93.
Amino Acids - O-GlcNAcylation, like phosphorylation, is a dynamic and rapid posttranslational modification which regulates many cellular processes. Phosphorylation on tyrosine and O-GlcNAcylation... 相似文献
94.
Maryam Farshadi Behrooz Johari Elham Erfani Ezadyar Mazaher Gholipourmalekabadi Mahmoud Azami Hamid Madanchi Seyed Mohammad Amin Haramshahi Abazar Yari Ayoob Karimizade Reza Nekouian Ali Samadikuchaksaraei 《Cell biology international》2019,43(12):1379-1392
The mechanical property of bone tissue scaffolds is one of the most important aspects in bone tissue engineering that has remained problematic. In our previous study, we fabricated a three‐dimensional scaffold from nano‐hydroxyapatite/gelatin (nHA/Gel) and investigated its efficiency in promoting bone regeneration both in vitro and in vivo. In the present study, the effect of adding silicon carbide (SiC) on the mechanical and biological behaviors of the nHA/Gel/SiC and bone regeneration in vivo were determined. nHA and SiC were synthesized and characterized by the X‐ray diffraction pattern and transmission electron microscope image. Layer solvent casting, freeze drying, and lamination techniques were applied to prepare these scaffolds. Then, the biocompatibility and cell adhesion behavior of the synthesized nHA/Gel/SiC scaffolds were investigated. For in vivo studies, rats were categorized into three groups: blank defect, blank scaffold, and rat bone marrow mesenchymal stem cells (rBM‐MSCs)/scaffold. After 1, 4, and 12 weeks post‐injury, the rats were sacrificed and the calvaria were harvested. Sections with a thickness of 5 µm thickness were prepared and stained with hematoxylin–eosin and Masson's Trichrome, and immunohistochemistry was performed. Our results showed that SiC effectively increased the mechanical properties of the nHA/Gel/SiC scaffold. No significant differences were observed in biocompatibility, cell adhesion, and cytotoxicity of the nHA/Gel/SiC in comparison with the nHA/Gel nanocomposite. Based on histological and immunohistochemical studies, both osteogenesis and collagenization were significantly higher in the rBM‐MSCs/scaffold group, quantitatively and qualitatively. The present study strongly suggests the potential of SiC as an alternative strategy to improve the mechanical and biological properties of bone tissue engineering scaffolds, and shows that the pre‐seeded nHA/Gel/SiC scaffold with rBM‐MSCs improves osteogenesis in the engineered bone implant. 相似文献
95.
96.
Interaction mechanisms of human serum albumin (HSA) with safranal and crocin were studied using UV–Vis absorption, fluorescence quenching and circular dichroism (CD) spectroscopies as well as molecular docking techniques. Changes in absorbance and fluorescence of HSA upon interactions with both compounds were attributed to their binding to amino acid chromophores located in subdomains IIA and IIIA. Fluorescence secondary inner filter effect was excluded using 278 nm and 340 nm as the wavelengths of HSA's excitation and fluorescence while safranal and crocin absorbed at 320 nm and 445 nm, respectively. Stern-Volmer model revealed a static quenching mechanism involve the formation of non-fluorescent ground state complexes. Stern-Volmer, Hill, Benesi-Hilbrand and Scatchard models gave apparent binding constants ranged in 4.25 × 103 - 2.15 × 105 for safranal and 7.67 × 103 - 4.23 × 105 L mol?1 for crocin. CD measurements indicated that 13 folds of safranal and crocin unfolded the α-helix structure of HSA by 7.47–21.20%. In-silico molecular docking revealed selective exothermic binding of safranal on eight binding sites with binding energies ranged in ?3.969 to ?6.6.913 kcal/mol. Crocin exothermally bound to a new large pocket located on subdomain IIA (sudlow 1) with binding energy of ?12.922 kcal/mol.These results confirmed the formation of HSA stable complexes with safranal and crocin and contributed to our understanding for their binding characteristics (affinities, sites, modes, forces … etc.) and structural changes upon interactions. They also proved that HSA can solubilize and transport both compounds in blood to target tissues. The results are of high importance in determining the pharmacological properties of the two phytochemical compounds and for their future developments as anticancer, antispasmodic, antidepressant or aphrodisiac therapeutic agents. 相似文献
97.
Soghomonyan S Hajitou A Rangel R Trepel M Pasqualini R Arap W Gelovani JG Alauddin MM 《Nature protocols》2007,2(2):416-423
Non-invasive imaging of transgene expression requires the appropriate combination of a reporter gene and a reporter probe. [18F]FEAU positron emission tomography (PET) is used for the assessment of herpes simplex virus type-1 thymidine kinase gene expression. Hybrid AAV phage (termed AAVP) can be adapted to transduce mammalian cells by targeting to a specific receptor. We evaluated a targeted AAVP vector using [18F]FEAU PET. This protocol describes [18F]FEAU production and dosing, micro-PET imaging and image analysis. 2-Deoxy-2-trifluoromethanesulfonyl-1,3,5-tri-O-benzoyl-alpha-D-ribofuranose is radio-fluorinated, converted into its 1-bromo derivative and coupled with protected 5-ethyl uracil. The coupled product is hydrolyzed and purified using HPLC. Tumor-bearing animals targeted with either retroviral or AAVP vectors are anesthetized and injected with [18F]FEAU (0.1 mCi per mouse); this is followed 2 h after injection by imaging on a micro-PET. Production of [18F]FEAU requires approximately 3.5 h from the end of bombardment. PET imaging studies require 2-3 h (depending on the number of animals) after synthesis of [18F]FEAU. 相似文献
98.
Normal Cdk5 activity, conferred mainly by association with its primary activator p35, is critical for normal function of the cell and must be tightly regulated. During neurotoxicity, p35 is cleaved to form p25, which becomes a potent and mislocalized hyperactivator of Cdk5, resulting in a deregulation of Cdk5 activity. p25 levels have been found to be elevated in Alzheimer's disease (AD) brain and overexpression of p25 in a transgenic mouse results in the formation of phosphorylated tau, neurofibrillary tangles and cognitive deficits that are pathological hallmarks of AD. p25/Cdk5 also hyperphosphorylates neurofilament proteins that constitute pathological hallmarks found in Parkinson's disease and amyotrophic lateral sclerosis. The selective targeting of p25/Cdk5 activity without affecting p35/Cdk5 activity has been unsuccessful. In this review we detail our recent studies of selective p25/Cdk5 inhibition without affecting p35/Cdk5 or mitotic Cdk activities. We found that a further truncation of p25 to yield a Cdk5 inhibitory peptide (CIP) can specifically inhibit p25/Cdk5 activity in transfected HEK cells and primary cortical neurons. CIP was able to reduce tau hyperphosphorylation and neuronal death induced caused by p25/Cdk5 and further studies with CIP may develop a specific Cdk5 inhibition strategy in the treatment of neurodegeneration. 相似文献
99.
Methods to produce marker-free transgenic plants 总被引:2,自引:0,他引:2
Selectable marker genes (SMGs) have been extraordinarily useful in enabling plant transformation because of the low efficiency of transgene integration. The most used SMGs encode proteins resistant to antibiotics or herbicides and use negative selection, i.e., by killing nontransgenic tissue. However, there are perceived risks in wide-scale deployment of SMG-transgenic plants, and therefore research has recently been performed to develop marker-free systems. In this review, transformation using markers not based on antibiotic or herbicide resistance genes, as well as different systems of marker gene deletion, are discussed. 相似文献
100.