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941.
Samadi N. Saeidi-Sar S. Abbaspour H. Masoudian N. 《Russian Journal of Plant Physiology》2020,67(1):131-138
Russian Journal of Plant Physiology - ‘Red Cloud’ (RC) is a cultivar of tomato (Solanum lycopersicum L.) which one of the main agricultural products classified as cultivated plants, it... 相似文献
942.
Syed Shan‐e‐Ali Zaidi Rubab Zahra Naqvi Muhammad Asif Susan Strickler Sara Shakir Muhammad Shafiq Abdul Manan Khan Imran Amin Bharat Mishra M. Shahid Mukhtar Brian E. Scheffler Jodi A. Scheffler Lukas A. Mueller Shahid Mansoor 《Plant biotechnology journal》2020,18(3):691-706
Cultivated cotton (Gossypium hirsutum) is the most important fibre crop in the world. Cotton leaf curl disease (CLCuD) is the major limiting factor and a threat to textile industry in India and Pakistan. All the local cotton cultivars exhibit moderate to no resistance against CLCuD. In this study, we evaluated an exotic cotton accession Mac7 as a resistance source to CLCuD by challenging it with viruliferous whiteflies and performing qPCR to evaluate the presence/absence and relative titre of CLCuD‐associated geminiviruses/betasatellites. The results indicated that replication of pathogenicity determinant betasatellite is significantly attenuated in Mac7 and probably responsible for resistance phenotype. Afterwards, to decipher the genetic basis of CLCuD resistance in Mac7, we performed RNA sequencing on CLCuD‐infested Mac7 and validated RNA‐Seq data with qPCR on 24 independent genes. We performed co‐expression network and pathway analysis for regulation of geminivirus/betasatellite‐interacting genes. We identified nine novel modules with 52 hubs of highly connected genes in network topology within the co‐expression network. Analysis of these hubs indicated the differential regulation of auxin stimulus and cellular localization pathways in response to CLCuD. We also analysed the differential regulation of geminivirus/betasatellite‐interacting genes in Mac7. We further performed the functional validation of selected candidate genes via virus‐induced gene silencing (VIGS). Finally, we evaluated the genomic context of resistance responsive genes and found that these genes are not specific to A or D sub‐genomes of G. hirsutum. These results have important implications in understanding CLCuD resistance mechanism and developing a durable resistance in cultivated cotton. 相似文献
943.
Tahmoorespur Mojtaba Azghandi Marjan Javadmanesh Ali Meshkat Zahra Sekhavati Mohammad Hadi 《International journal of peptide research and therapeutics》2020,26(3):1593-1605
International Journal of Peptide Research and Therapeutics - In the present study, a novel chimeric peptide was derived from camel lactoferrin designed with a considerable anti-HCV activity and its... 相似文献
944.
Zahra Andaji‐Garmaroudi Miguel Anaya Andrew J. Pearson Samuel D. Stranks 《Liver Transplantation》2020,10(13)
There has been a meteoric rise in the commercial potential of lead halide perovskite optoelectronic devices since photovoltaic cells and light‐emitting diodes based on these materials were first demonstrated. One key challenge common to each of these optoelectronic devices is the need to suppress nonradiative recombination, a process that limits the maximum achievable efficiency in photovoltaic cells and light‐emitting diodes. In this Progress Report, recent studies that seek to minimize this loss pathway in perovskites through a photobrightening treatment, whereby the luminescence efficiency is enhanced through a light illumination passivation process are examined. The sensitivity of this effect to various experimental considerations is examined, including atmosphere, photon energy, photon dose, and also the role of perovskite composition and morphology; under certain conditions there can even be photodarkening effects. Consideration of these factors is critical to resolve seemingly conflicting literature reports. Proposed mechanisms are scrutinized, revealing that there is now some consensus but further work is needed to identify the specific defects being passivated and elucidate universal mechanisms. Finally, the prospects for these treatments to minimize halide migration and push the properties of polycrystalline films towards those of their single‐crystal counterparts are discussed. 相似文献
945.
946.
To predict P sorption and leaching behavior in calcareous soils, we examined the adsorption and movement of applied P in columns of two calcareous soils. Phosphorus and various other ions were monitored in the leachate of the soil column by passing a 100 mg P l?1 solution through the soil column. Concentrations of P, K+, Ca2+, Mg2+, Na+, HCO? 3, Cl?, EC and pH were determined in the leachates. Movement of K+ and P ions was retarded due to K+ ion-exchange and P adsorption and precipitation, respectively. Phosphorus leaching was affected by supersaturation with respect to P-Ca minerals, but undersaturated with respect to Mg-P minerals. Phosphorus retention based on batch and miscible displacement experiments revealed profound discrepancies that can be attributed to the short residence time of P in the miscible displacement. Breakthrough curves of P and K+ were analyzed by a CXTFIT program. The equilibrium model provides good results to the transport process of P and K+. Results indicated that the mobility of P in these calcareous soils reflects that a high downward movement of water-soluble P in soils may occur and much attention should be paid to leaching of P and potential contamination of P to surface and ground waters. 相似文献
947.
Zahra Moradpour Abdollah Ghasemian Azam Safari Milad Mohkam Younes Ghasemi 《Annals of microbiology》2013,63(3):941-950
The current work details the screening of about 100 isolates from various soil samples, from which 1 isolate was finally selected based on the productivity of cholesterol oxidase. Further biochemical identification tests and 16S rRNA gene sequencing identified this isolate as Streptomyces badius. A preliminary culture media optimization was carried out using the initial screening method of Plackett-Burman. Then, a Box-Behnken design was employed to investigate the optimum concentrations of medium components and interactive effects of main variables on cholesterol oxidase production. The regression analysis showed a significant coefficient of determination (R 2) value (91 %), which was in close agreement ensuring a satisfactory adjustment of the proposed model. Maximal enzyme production (2.38 U/mL, i.e., approximately more than 100 % activity in the basal medium) was obtained at: temperature 35 °C; Tween 20 0.1 %; pH 6.5 and yeast extract 0.15 %. This two-stage statistical approach provided rapid identification and integration of key medium parameters for Streptomyces sp., resulting in high cholesterol oxidase production. 相似文献
948.
P. Samadi A. Boutet V. V. Rymar K. Rawal J. Maheux J.‐C. Kvann M. Tomaszewski F. Beaubien J. F. Cloutier D. Levesque A. F. Sadikot 《Genes, Brain & Behavior》2013,12(1):108-124
Patients with Huntington's disease (HD) and transgenic mouse models of HD show neuronal loss in the striatum as a major feature, which contributes to cognitive and motor manifestations. Reduced expression of the neurotrophin brain‐derived neurotrophic factor (BDNF) in striatal afferents may play a role in neuronal loss. How progressive loss of BDNF expression in different cortical or subcortical afferents contributes to striatal atrophy and behavioral dysfunction in HD is not known, and may best be determined in animal models. We compared age‐dependent alterations of BDNF mRNA expression in major striatal afferents from the cerebral cortex, thalamus and midbrain in the R6/2 transgenic mouse model of HD. Corresponding changes in striatal morphology were quantified using unbiased stereology. Changes in motor behavior were measured using an open field, grip strength monitor, limb clasping and a rotarod apparatus. BDNF expression in cortical limbic and midbrain striatal afferents is reduced by age 4 weeks, prior to onset of motor abnormalities. BDNF expression in motor cortex and thalamic afferents is reduced by 6 weeks, coinciding with early motor dysfunction and reduced striatum volume. BDNF loss in afferents progresses until death at 13–15 weeks, correlating with progressive striatal neuronal loss and motor abnormalities. Mutant huntingtin protein expression in R6/2 mice results in progressive loss of BDNF in both cortical and subcortical striatal afferents. BDNF loss in limbic and dopaminergic striatal inputs may contribute to cognitive/psychiatric dysfunction in HD. Subsequent BDNF loss in cortical motor and thalamic afferents may accelerate striatal degeneration, resulting in progressive involuntary movements. 相似文献
949.
Researchers increasingly believe that microbial, molecular and synthetic biology techniques along with genetic engineering will facilitate the treatment of persistent infectious diseases. However, such therapy has been plagued by the emergence of antibiotic-resistant bacteria, resulting in significant obstacles to treatment. Phage therapy is one promising alternative to antibiotics, especially now that recent modifications to ubiquitous phages have made them more controllable. Additionally, convincing in vitro and in vivo studies of genetically modified lytic phages and engineered non-lytic phages have confirmed the advantages of novel, specific bactericidal agents over antibiotics in some cases. There is still a need for a better understanding of phage therapy, however, before it can be adopted widely. 相似文献
950.
Cell transplantation shows potential for the treatment of cardiac diseases. Embryonic stem cells, cord blood and mesenchymal stem cells have been suggested as sources for transplantation therapy. Because of some technical limitations with the use of stem cells, transdifferentiation of fully differentiated cells is a potentially useful alternative. We investigated whether human peripheral blood cells could transdifferentiate into cardiomyocyte. Transdifferentiation was induced in a human B lymphocyte cell line (Raji). Cardiomyocyte extract was prepared from adult mouse cardiomyocytes. The cells were treated with 5-aza-2-deoxycytidine and trichostatin A, permeabilized with streptolysin O, and exposed to the mouse cardiomyocyte extract. They were cultured for 10 days, 3 weeks and 4 weeks. Cardiomyocyte markers were detected with immunohistochemistry and flow cytometry. Immunocytochemistry revealed that some cells expressed myosin heavy chain, α-actinin and cardiac troponin T after 3 and 4 weeks. Flow cytometry confirmed these data. In cells exposed to trichostatin A and 5-aza-2-deoxycytidine and permeabilized in the presence of the cardiomyocyte extract, troponin T expression was seen in 3.53% of the cells and 3.11% of them expressed α-actinin. After exposure to the cardiomyocyte extract, some permeabilized cells adhered to the plate loosely; however, the morphology did not change significantly, and they continued to show a rounded shape after 4 weeks. Our treated lymphocytes expressed cardiomyocyte markers. Our results suggest that lymphocytes may be useful in future research as a source of cells for reprogramming procedures. 相似文献