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41.
The distribution of d(CT)-rich pyrimidine tracts in the karyotypes of a variety of vertebrates was studied by in situ hybridization. The probe for these studies was a 56 bp homopyrimidine/homopurine sequence obtained from a mouse genomic library constructed with DNA prepared from a restriction enzyme digestion of metaphase chromosomes. Single-stranded DNA nuclease digestions and two-dimensional gel analysis of topoisomers of this sequence indicated that it is capable of adopting a triplex conformation in vitro. In situ hybridization with this probe to the karyotypes of ten different vertebrate species revealed a highly conserved chromosomal distribution of d(CT)-rich tracts. These tracts are found throughout the chromosomal arms and in some karyotypes they are clustered, producing a banding pattern. However, at the resolution of the light microscope these tracts appeared to be absent from the centromeric regions of all chromosomes examined except those of chicken. The non-random distribution of these tracts to the chromosomal arm regions implies an organizational or functional role for this repeat class. It is unlikely that the 56 bp sequence type contributed to the formation of the triplex DNA structure previously detected in centromeric domains of mouse. 相似文献
42.
Mickaël Mateos Nikolina Makivic Yee‐Seul Kim Benoît Limoges Vronique Balland 《Liver Transplantation》2020,10(23)
Rechargeable batteries based on MnO2 cathodes, able to operate in mild aqueous electrolytes, have attracted attention due to their appealing features for the design of low‐cost stationary energy storage devices. However, the charge/discharge mechanism of MnO2 in such media is still a matter of debate. Here, an in‐depth quantitative spectroelectrochemical analysis of MnO2 thin‐films provides a set of unrivaled mechanistic insights. A major finding is that charge storage occurs through the reversible two‐electron faradaic conversion of MnO2 into Mn2+ in the presence of a wide range of weak Brønsted acids, including the [Zn(H2O)6]2+ or [Mn(H2O)6]2+ complexes present in aqueous Zn/MnO2 batteries. Furthermore, it is shown that buffered electrolytes loaded with Mn2+ are ideal to achieve highly reversible conversion of MnO2 with both high gravimetric capacity and remarkably stable charging/discharging potentials. In the most favorable case, a record gravimetric capacity of 450 mA·h·g?1 is obtained at a high rate of 1.6 A·g?1, with a Coulombic efficiency close to 100% and a MnO2 utilization of 84%. Overall, the present results challenge the common view on MnO2 the charge storage mechanism in mild aqueous electrolytes and underline the benefit of buffered electrolytes for high‐performance rechargeable aqueous batteries. 相似文献
43.
This review summarizes recent literature for applying pharmacogenomics to antifungal selection and dosing, providing an approach to implementing antifungal pharmacogenomics in clinical practice. The Clinical Pharmacogenetics Implementation Consortium published guidelines on CYP2C19 and voriconazole, with recommendations to use alternative antifungals or adjust voriconazole dose with close therapeutic drug monitoring (TDM). Recent studies demonstrate an association between CYP2C19 phenotype and voriconazole levels, clinical outcomes, and adverse events. Additionally, CYP2C19-guided preemptive dose adjustment demonstrated benefit in two prospective studies for prophylaxis. Pharmacokinetic–pharmacodynamic modeling studies have generated proposed voriconazole treatment doses based on CYP2C19 phenotypes, with further validation studies needed. Sufficient evidence is available for implementing CYP2C19-guided voriconazole selection and dosing among select patients at risk for invasive fungal infections. The institution needs appropriate infrastructure for pharmacogenomic testing, integration of results in the clinical decision process, with TDM confirmation of goal trough achievement, to integrate antifungal pharmacogenomics into routine clinical care. 相似文献
44.
Olivier Maurin Artemis Anest Sidonie Bellot Edward Biffin Grace Brewer Tristan Charles-Dominique Robyn S. Cowan Steven Dodsworth Niroshini Epitawalage Berta Gallego Augusto Giaretta Renato Goldenberg Deise J.P. Gonçalves Shirley Graham Peter Hoch Fiorella Mazine Yee Wen Low Catherine McGinnie Fabián A. Michelangeli Sarah Morris Darin S. Penneys Oscar Alejandro Pérez Escobar Yohan Pillon Lisa Pokorny Gustavo Shimizu Vanessa G. Staggemeier Andrew H. Thornhill Kyle W. Tomlinson Ian M. Turner Thais Vasconcelos Peter G. Wilson Alexandre R. Zuntini William J. Baker Félix Forest Eve Lucas 《American journal of botany》2021,108(7):1087-1111
45.
Figs have been regarded as keystone plant resources that support diverse tropical vertebrate frugivore communities. Planting or conserving large fig trees, such as stranglers, have therefore been proposed for enhancing urban biodiversity. We compared the diversity and community structure of bird assemblages on strangler figs with non‐fig urban trees as well as between the fruiting and non‐fruiting fig trees in an urban setting in Singapore. The total bird abundance across all the fig trees when in fruit was 4.5‐fold higher than on non‐fig trees and 3.5‐fold higher than when the same fig trees were not fruiting, but only attracted two more species. On individual trees, after accounting for the presence of mistletoes, tree height, the area covered by buildings, road lane density, and the distance to natural vegetation, mean diversity was not different between non‐fig trees and fig trees when they were not in fruit. On the other hand, when fruiting, each fig tree on average had 1.4 more species, 3 more counts of non‐native birds, and 1.6 more counts of insectivorous birds than when not fruiting. There was significant compositional turnover between non‐fig trees and non‐fruiting fig trees, while community dispersion was significantly lower among fig trees in fruit. Our results demonstrate that fig trees provide fruit and non‐fruit resources for birds in an urban landscape but do not necessarily support more diverse total bird assemblages than non‐fig trees. Instead, bird communities on fruiting urban figs would be highly homogeneous and dominated by a few species. Abstract in Malay is available with online material. 相似文献
46.
Jang Hye Jin Choi Ji Yeon Kim Kangjoon Yong Seung Hyun Kim Yeon Wook Kim Song Yee Kim Eun Young Jung Ji Ye Kang Young Ae Park Moo Suk Kim Young Sam Cho Young-Jae Lee Sang Hoon 《Respiratory research》2021,22(1):1-9
IL-35 subunit EBI3 is up-regulated in pulmonary fibrosis tissues. In this study, we investigated the pathological role of EBI3 in pulmonary fibrosis and dissected the underlying molecular mechanism. Bleomycin-induced pulmonary fibrosis mouse model was established, and samples were performed gene expression analyses through RNAseq, qRT-PCR and Western blot. Wild type and EBI3 knockout mice were exposed to bleomycin to investigate the pathological role of IL-35, via lung function and gene expression analyses. Primary lung epithelial cells were used to dissect the regulatory mechanism of EBI3 on STAT1/STAT4 and STAT3. IL-35 was elevated in both human and mouse with pulmonary fibrosis. EBI3 knockdown aggravated the symptoms of pulmonary fibrosis in mice. EBI3 deficiency enhanced the expressions of fibrotic and extracellular matrix-associated genes. Mechanistically, IL-35 activated STAT1 and STAT4, which in turn suppressed DNA enrichment of STAT3 and inhibited the fibrosis process. IL-35 might be one of the potential therapeutic targets for bleomycin-induced pulmonary fibrosis. 相似文献
47.
Chua Fu Yee Novakovic Zachary M. Grasso Patricia 《International journal of peptide research and therapeutics》2021,27(4):2223-2230
International Journal of Peptide Research and Therapeutics - Oral delivery of MA-[d-Leu-4]-OB3 has been shown to significantly improve energy balance, glycemic control, dyslipidemia, and episodic... 相似文献
48.
Xiu-Ping Zhang Qinjunjie Chen Qu Liu Yang Wang Fei Wang Zhi-Ming Zhao Guo-Dong Zhao Wan Yee Lau Yu-Zhen Gao Rong Liu 《Journal of cellular and molecular medicine》2021,25(12):5615-5627
Pancreatic ductal adenocarcinoma (PDAC) is a lethal malignancy with aggressive biological behaviour. Its rapid proliferation and tumour growth require reprogramming of glucose metabolism or the Warburg effect. However, the association between glycolysis-related genes with clinical features and prognosis of PDAC is still unknown. Here, we used the meta-analysis to correlate the hazard ratios (HR) of 106 glycolysis genes from MSigDB by the cox proportional hazards regression analysis in 6 clinical data sets of PDAC patients to form a training cohort, and a single group of PDAC patients from the TCGA, ICGC, Arrayexpress and GEO databases to form the validation cohort. Then, a glycolysis-related prognosis (GRP) score based on 29 glycolysis prognostic genes was established in 757 PDAC patients from the training composite cohort and validated in 267 ICGC-CA validation cohort (all P < .05). In addition, including PADC, the prognostic value was also confirmed in other 7 out of 30 pan-cancer cohorts. The GRP score was significantly related to specific metabolism pathways, immune genes and immune cells in the patients with PADC (all P < .05). Finally, by combining with immune cells, the GRP score also well-predicted the chemosensitivity of patients with PADC in the TCGA cohort (AUC = 0.709). In conclusion, this study developed a GRP score for patients with PDAC in predicting prognosis and chemosensitivity for PDAC. 相似文献
49.
Yee Han Kuan Foad Kabinejadian Vinh-Tan Nguyen Boyang Su Ajit P. Yoganathan 《Computer methods in biomechanics and biomedical engineering》2013,16(16):1785-1796
The characterization of the bileaflet mechanical heart valves (BMHVs) hinge microflow fields is a crucial step in heart valve engineering. Earlier in vitro studies of BMHV hinge flow at the aorta position in idealized straight pipes have shown that the aortic sinus shapes and sizes may have a direct impact on hinge microflow fields. In this paper, we used a numerical study to look at how different aortic sinus shapes, the downstream aortic arch geometry, and the location of the hinge recess can influence the flow fields in the hinge regions. Two geometric models for sinus were investigated: a simplified axisymmetric sinus and an idealized three-sinus aortic root model, with two different downstream geometries: a straight pipe and a simplified curved aortic arch. The flow fields of a 29-mm St Jude Medical BMHV with its four hinges were investigated. The simulations were performed throughout the entire cardiac cycle. At peak systole, recirculating flows were observed in curved downsteam aortic arch unlike in straight downstream pipe. Highly complex three-dimensional leakage flow through the hinge gap was observed in the simulation results during early diastole with the highest velocity at 4.7 m/s, whose intensity decreased toward late diastole. Also, elevated wall shear stresses were observed in the ventricular regions of the hinge recess with the highest recorded at 1.65 kPa. Different flow patterns were observed between the hinge regions in straight pipe and curved aortic arch models. We compared the four hinge regions at peak systole in an aortic arch downstream model and found that each individual hinge did not vary much in terms of the leakage flow rate through the valves. 相似文献
50.