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91.
The sustainability of global crop production is critically dependent on improving tolerance of crop plants to various types of environmental stress. Thus, identification of genes that confer stress tolerance in crops has become a top priority especially in view of expected changes in global climatic patterns. Drought stress is one of the abiotic stresses that can result in dramatic loss of crop productivity. In this work, we show that transgenic expression of a highly conserved cell death suppressor, Bax Inhibitor‐1 from Arabidopsis thaliana (AtBI‐1), can confer increased tolerance of sugarcane plants to long‐term (>20 days) water stress conditions. This robust trait is correlated with an increased tolerance of the transgenic sugarcane plants, especially in the roots, to induction of endoplasmic reticulum (ER) stress by the protein glycosylation inhibitor tunicamycin. Our findings suggest that suppression of ER stress in C4 grasses, which include important crops such as sorghum and maize, can be an effective means of conferring improved tolerance to long‐term water deficit. This result could potentially lead to improved resilience and yield of major crops in the world.  相似文献   
92.
The azoles are the class of medications most commonly used to fight infections caused by Candida sp. Typically, resistance can be attributed to mutations in ERG11 gene (CYP51) which encodes the cytochrome P450 14α-demethylase, the primary target for the activity of azoles. The objective of this study was to identify mutations in the coding region of theERG11 gene in clinical isolates of Candidaspecies known to be resistant to azoles. We identified three new synonymous mutations in the ERG11 gene in the isolates of Candida glabrata (C108G, C423T and A1581G) and two new nonsynonymous mutations in the isolates of Candida krusei - A497C (Y166S) and G1570A (G524R). The functional consequence of these nonsynonymous mutations was predicted using evolutionary conservation scores. The G524R mutation did not have effect on 14α-demethylase functionality, while the Y166S mutation was found to affect the enzyme. This observation suggests a possible link between the mutation and dose-dependent sensitivity to voriconazole in the clinical isolate of C. krusei. Although the presence of the Y166S in phenotype of reduced azole sensitivity observed in isolate C. kruseidemands investigation, it might contribute to the search of new therapeutic agents against resistant Candida isolates.  相似文献   
93.
Aluminum (Al) resistance of 57 Madeiran wheat cultivars was evaluated using callose content in root tips and root elongation as markers. Al induced callose formation was a very sensitive indicator of Al damage detecting wide range of genotypic differences existing in the Madeiran wheat germplasm. A weak, yet positive correlation (R2=0.285, P<0.05) between callose content and root elongation was found.  相似文献   
94.
Mechanobiology is focused on how the physical forces and mechanical properties of proteins, cells, and tissues contribute to physiology and disease. Although the response of proteins and cells to mechanical stimuli is critical for function, the tools to probe these activities are typically restricted to single-molecule manipulations. Here, we have developed a novel microplate reader assay to encompass mechanical measurements with ensemble biochemical and cellular assays, using a microplate lid modified with magnets. This configuration enables multiple static magnetic tweezers to function simultaneously across the microplate, thereby greatly increasing throughput. We demonstrate the broad applicability and versatility through in vitro and in cellulo approaches. Overall, our methodology allows, for the first time (to our knowledge), ensemble biochemical and cell-based assays to be performed under force in high-throughput format. This approach substantially increases the availability of mechanobiology measurements.  相似文献   
95.
Neurochemical Research - Interleukin-2 (IL-2) is a classical pro-inflammatory cytokine known to display neuroprotective roles in the central nervous system including the retina. In the present...  相似文献   
96.
The first checklist of the Peruvian Hymenoptera listed 1169 species and subspecies of aculeate wasps, including 173 species of Pompilidae, seven of Scoliidae, 39 of Sphecidae and 403 of Vespidae. Herein are reported 32 species as new for Peru based mainly on the collection of the Natural History Museum, London. The loss of the endemic status of two species is also reported: Entypus peruvianus (Rohwer) (Pompilidae: Pepsinae) and Omicron ruficolle schunkei Giordani Soika (Vespidae: Eumeninae).  相似文献   
97.
98.
Honey and bee bread samples from storage pots of Melipona quadrifasciata anthidioides were collected monthly from April 2015 to May 2016 in the Mogi Guaçu Biological Reserve (22º 10? S, 47º 11? W). The flora in the site is characteristic of the Atlantic Forest with preserved areas of savanna-like vegetation surrounded by commercial forests, orchards and various crops of exotic and native plants. Samples were analysed with the use of melissopalynological methodology and 46 pollen types from 38 genera and 30 families were identified in 25 honey samples. Fabaceae, Asteraceae, Myrtaceae, Sapindaceae showed the greatest pollen richness in honey. Predominant nectariferous pollen types were Anadenanthera, Cordia, Eucalyptus, Mimosa scabrella, Schefflera, Sida, Serjania and Vernonia. Twenty-eight types of pollen from 21 genera and 19 families were identified in 22 bee bread samples. Fabaceae, Asteraceae and Myrtaceae showed the highest pollen richness. Anadenanthera, Cecropia, Eucalyptus, Melastomataceae, Mimosa scabrella, Mimosa verrucosa and Myrcia were the most frequent polliniferous pollen types. Principal component analysis (PCA) demonstrated that honey and pollen samples formed two main groups of similarity, mainly due to Eucalyptus’ nectar and pollen of Melastomataceae, respectively. Melipona quadrifasciata anthidioides collected nectar and pollen from the preserved areas as well as in the secondary and ‘ruderal’ vegetation and in cultivated forests/fields, suggesting their importance as pollinators both of native flora and exotic species. The use of trophic resources of plants grown with pesticides is a concern for the conservation of these species of bee and should be better studied.  相似文献   
99.
We register for first time the occurrence of Epipompilus tucumanus Evans, 1967 in Brazil, and record the spider Ariadna boliviana Simon, 1907 as its host. The observations were made in the National Park of Chapada dos Guimarães, Mato Grosso, Brazil. The prey carriage mechanism is described for first time for this genus, and we provide a video showing this behavior.  相似文献   
100.
Several studies have shown the mechanisms and importance of immune responses against Toxoplasma gondii infection and the notable role of cholinesterases in inflammatory reactions. However, the association between those factors has not yet been investigated. Therefore, the aim of this study was to evaluate the acetylcholinesterase (AChE) activity in blood and lymphocytes and the activity of butyrylcholinesterase (BChE) in serum of rats experimentally infected with T. gondii during the acute phase of infection. For that, an in vivo study was performed with evaluations of AChE and BChE activities on days 5 and 10 post-infection (PI). The activity of AChE in blood was increased on day 5 PI, while in lymphocytes its activity was enhanced on days 5 and 10 PI (P<0.05). No significant difference was observed between groups regarding to the activity of BChE in serum. A positive (P<0.01) correlation was observed between AChE activity and number of lymphocytes. The role of AChE as an inflammatory marker is well known in different pathologies; thus, our results lead to the hypothesis that AChE has an important role in modulation of early immune responses against T. gondii infection.  相似文献   
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