目的: 观察健康志愿者不同功率递增速率完成症状限制性极限心肺运动试验(CPET)对CPET亚极限运动相关核心指标的影响。方法: 选择12名健康志愿者在一周内不同工作天随机完成中等适度程度(30 W/min)及比较低(10 W/min)和比较高(60 W/min)3种不同功率递增速率CPET。按标准方法比较12名志愿者CPET亚极限运动相关核心指标:无氧阈(AT)、单位功率摄氧量(ΔVO2/ΔWR)、摄氧通气有效性峰值平台(OUEP)、二氧化碳通气当量平均90 s最低值(Lowest VE/ VCO2)、二氧化碳通气当量斜率(VE/ VCO2 Slope)及截距(intercept)和无氧阈时的摄氧通气效率值(VO2/ VE@AT)和无氧阈时的二氧化碳通气当量值(VE/ VCO2@AT)。对三组不同功率递增速率下各个指标的差异组间两两比较。结果: 中等适度功率递增速率组与比较低和比较高功率递增速率组相比摄氧通气有效性峰值平台(42.22±4.76 vs 39.54±3.30 vs 39.29±4.29)和二氧化碳通气当量平均90 s最小值(24.13±2.88 vs 25.60±2.08 vs 26.06±3.05)明显好,差异有统计学意义(P<0.05);比较低、比较高功率递增速率组与中等适度功率递增速率组相比,单位功率摄氧量显著升高和降低((8.45±0.66 vs 10.04±0.58 vs 7.16±0.60)ml/(min·kg)),差异有统计学意义(P<0.05);无氧阈值没有发生明显改变((0.87±0.19 vs 0.87±0.19 vs 0.89±0.19)L/min),差异无统计学意义(P>0.05);结论: 比较低、比较高功率递增速率可以明显改变摄氧通气有效性、二氧化碳排出通气有效性、单位功率摄氧量等CPET亚极限运动相关指标;选择比较低和比较高的功率递增速率和适度功率递增速率CPET相比明显降低了健康个体的摄氧通气有效性和二氧化碳排出通气有效性。CPET规范化操作要求选择适合受试者的功率递增速率,这样得到的CPET亚极限相关指标才最能反应受试者的真实功能状态。 相似文献
Heterochromatin is widespread in eukaryotic genomes and has diverse impacts depending on its genomic context. Previous studies have shown that a protein complex, the ASI1‐AIPP1‐EDM2 (AAE) complex, participates in polyadenylation regulation of several intronic heterochromatin‐containing genes. However, the genome‐wide functions of AAE are still unknown. Here, we show that the ASI1 and EDM2 mostly target the common genomic regions on a genome‐wide level and preferentially interacts with genetic heterochromatin. Polyadenylation (poly(A) sequencing reveals that AAE complex has a substantial influence on poly(A) site usage of heterochromatin‐containing genes, including not only intronic heterochromatin‐containing genes but also the genes showing overlap with heterochromatin. Intriguingly, AAE is also involved in the alternative splicing regulation of a number of heterochromatin‐overlapping genes, such as the disease resistance gene RPP4. We provided evidence that genic heterochromatin is indispensable for the recruitment of AAE in polyadenylation and splicing regulation. In addition to conferring RNA processing regulation at genic heterochromatin‐containing genes, AAE also targets some transposable elements (TEs) outside of genes (including TEs sandwiched by genes and island TEs) for epigenetic silencing. Our results reveal new functions of AAE in RNA processing and epigenetic silencing, and thus represent important advances in epigenetic regulation. 相似文献
Nanocarriers for encapsulation and sustained release of agrochemicals such as auxins have emerged as an attractive strategy to provide enhanced bioavailability and efficacy for improved crop yields and nutrition quality. Here, a comparative study was conducted on the effectiveness of chitosan-as a biopolymeric nanocarrier- and silver-as a metallic nanocarrier- on in vitro adventitious rooting potential of microcuttings in apple rootstocks, for the first time. Auxins indole-3-acetic acid (IAA) and indole-3-butyric acid (IBA) loaded silver (nAg) or chitosan nanoparticles (nChi) were synthesized. Scanning electron microscopy and transmission electron microscopy studies showed the spherical shape of the nanoparticles. The average particle size of IAA-nChi was 167.5 ± 0.1 nm while that of IBA-nChi was 123.2 ± 2.6 nm. The hydrodynamic diameter of the nAg-IAA and nAg-IBA particles were measured as 93.66 ± 5 nm and 71.41 ± 3 nm, respectively. Fourier transform infrared spectroscopy analyses confirmed the encapsulation of IAA or IBA in the chitosan nanoparticles. Meanwhile, the characteristic peaks of IAA or IBA were detected on silver nanoparticles. In-vitro adventitious rooting of microcuttings of Malling Merton 106 (MM 106) was significantly higher both in chitosan and silver nanoparticles loaded with IAA or IBA (91.7%–62.5%) compared to free IAA or IBA applications (50.0%–33.3%), except for 2.0 mg L–1 IBA (66.7%). However, the application of 2 mg L–1 IBA and IBA-nChi at all concentrations caused an undesirable large callus development. 相似文献
Therapies that utilize immune checkpoint inhibition work by leveraging mutation-derived neoantigens and have shown greater clinical efficacy in tumors with higher mutational burden. Whether tumors with a low mutational burden are susceptible to neoantigen-targeted therapy has not been fully addressed. To examine the feasibility of neoantigen-specific adoptive T-cell therapy, the authors studied the T-cell response against somatic variants in five patients with myelodysplastic syndrome (MDS), a malignancy with a very low tumor mutational burden. DNA and RNA from tumor (CD34+) and normal (CD3+) cells isolated from the patients’ blood were sequenced to predict patient-specific MDS neopeptides. Neopeptides representing the somatic variants were used to induce and expand autologous T cells ex vivo, and these were systematically tested in killing assays to determine the proportion of neopeptides yielding neoantigen-specific T cells. The authors identified a total of 32 somatic variants (four to eight per patient) and found that 21 (66%) induced a peptide-specific T-cell response and 19 (59%) induced a T-cell response capable of killing autologous tumor cells. Of the 32 somatic variants, 11 (34%) induced a CD4+ response and 11 (34%) induced a CD8+ response that killed the tumor. These results indicate that in vitro induction of neoantigen-specific T cells is feasible for tumors with very low mutational burden and that this approach warrants investigation as a therapeutic option for such patients. 相似文献
Adenosine triphosphate (ATP) and its metabolites adenosine diphosphate, adenosine monophosphate, and adenosine in purinergic signaling pathway play important roles in many diseases. Activation of P2 receptors (P2R) channels and subsequent membrane depolarization can induce accumulation of extracellular ATP, and furtherly cause kinds of diseases, such as pain- and immune-related diseases, cardiac dysfunction, and tumorigenesis. Active ingredients of traditional Chinese herbals which exhibit superior pharmacological activities on diversified P2R channels have been considered as an alternative strategy of disease treatment. Experimental evidence of potential ingredients in Chinese herbs targeting P2R and their pharmacological activities were outlined in the study.