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51.
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
52.
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
53.
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
54.
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
55.
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
56.
57.
MicroRNA-199a (miRNA-199a) has been shown to have comprehensive functions and behave differently in different systems and diseases. It is encoded by two loci in the human genome, miR-199a-1 in chromosome 19 and miR-199a-2 in chromosome 1. Both loci give rise to the same miRNAs (miR-199a-5p and miR-199a-3p). The cause of the diverse action of the miRNA in different systems is not clear. However, it is likely due to different regulation of the two genomic loci and variable targets of the miRNA in different cells and tissues. Here we studied promoter methylation of miR-199a in testicular germ cell tumors (TGCTs) and glioblastomas (gliomas) and discovered that hypermethylation in TGCTs of both miR-199a-1 and -2 resulted in its reduced expression, while hypomethylation of miR-199a-2 but not -1 in gliomas may be related to its elevated expression. We also identified a common regulator, REST, which preferentially bound to the methylated promoters of both miR-199a-1 and miR-199a-2. The action of miR-199a is dependent on its downstream targets. We identified MAFB as a putative target of miRNA-199a-5p in TGCTs and confirmed that the tumor suppression activity of the microRNA is mediated by its target MAFB. By studying the mechanisms that control the expressions of miR-199a and its various downstream targets, we hope to use miR-199a as a model to understand the complexity of miRNA biology. 相似文献
58.
Mojgan Nazari Sue Yee Lim Mahira Watanabe Reuben S. K. Sharma Nadzariah A. B. Y. Cheng Malaika Watanabe 《PLoS neglected tropical diseases》2013,7(1)
An epidemiological study of Ehrlichia canis infection in dogs in Peninsular Malaysia was carried out using molecular detection techniques. A total of 500 canine blood samples were collected from veterinary clinics and dog shelters. Molecular screening by polymerase chain reaction (PCR) was performed using genus-specific primers followed by PCR using E. canis species-specific primers. Ten out of 500 dogs were positive for E. canis. A phylogenetic analysis of the E. canis Malaysia strain showed that it was grouped tightly with other E. canis strains from different geographic regions. The present study revealed for the first time, the presence of genetically confirmed E. canis with a prevalence rate of 2.0% in naturally infected dogs in Malaysia. 相似文献
59.
Cynthia Chen Nasheen Naidoo Benjamin Er Angela Cheong Ngan Phoon Fong Choo Yian Tay Kin Ming Chan Boon Yeow Tan Edward Menon Chye Hua Ee Kok Keng Lee Yee Sien Ng Yik Ying Teo Gerald C. H. Koh 《PloS one》2013,8(12)