BACKGROUND Iterative decomposition of water and fat with echo asymmetry and least squares estimation quantification sequence(IDEAL-IQ)is based on chemical shift-based water and fat separation technique to get proton d...BACKGROUND Iterative decomposition of water and fat with echo asymmetry and least squares estimation quantification sequence(IDEAL-IQ)is based on chemical shift-based water and fat separation technique to get proton density fat fraction.Multiple studies have shown that using IDEAL-IQ to test the stability and repeatability of liver fat is acceptable and has high accuracy.AIM To explore whether Gadoxetate Disodium(Gd-EOB-DTPA)interferes with the measurement of the hepatic fat content quantified with the IDEAL-IQ and to evaluate the robustness of this technique.METHODS IDEAL-IQ was used to quantify the liver fat content at 3.0T in 65 patients injected with Gd-EOB-DTPA contrast.After injection,IDEAL-IQ was estimated four times,and the fat fraction(FF)and R2* were measured at the following time points:Precontrast,between the portal phase(70 s)and the late phase(180 s),the delayed phase(5 min)and the hepatobiliary phase(20 min).One-way repeated-measures analysis was conducted to evaluate the difference in the FFs between the four time points.Bland-Altman plots were adopted to assess the FF changes before and after injection of the contrast agent.P<0.05 was considered statistically significant.RESULTS The assessment of the FF at the four time points in the liver,spleen and spine showed no significant differences,and the measurements of hepatic FF yielded good consistency between T1 and T2[95%confidence interval:-0.6768%,0.6658%],T1 and T3(-0.3900%,0.3178%),and T1 and T4(-0.3750%,0.2825%).R2* of the liver,spleen and spine increased significantly after injection(P<0.0001).CONCLUSION Using the IDEAL-IQ sequence to measure the FF,we can obtain results that will not be affected by Gd-EOB-DTPA.The high reproducibility of the IDEAL-IQ sequence makes it available in the scanning interval to save time during multiphase examinations.展开更多
Background: Laying sequence has important effects on eggshell color and embryonic development in birds. Some birds can allocate resources unevenly among the eggs within a clutch, prioritizing those at the beginning of...Background: Laying sequence has important effects on eggshell color and embryonic development in birds. Some birds can allocate resources unevenly among the eggs within a clutch, prioritizing those at the beginning of the laying sequence, in order to maximize reproductive success. The changes in egg color according to laying sequence may be an adaptation to pressure from predators or brood parasites.Methods: In this study, effects of laying sequence on egg color and embryonic heart rate in Russet Sparrows(Passer cinnamomeus) were investigated using artificial nest boxes. The eggs were divided into three groups: first to be laid, intermediate in the laying sequence, and last to be laid. We maintained the eggs in an incubator and measured embryonic heart rates.Results: Avian visual modeling showed that the background color brightness of the last eggs laid was significantly higher(whiter) than those of the other eggs. All eggs were about the same size and hatched around 13 days, indicating that laying sequence significantly affected embryonic development speed; the last eggs to be laid developed significantly faster than did the first in the clutch.Conclusions: Our study quantified the effect of laying sequence on egg color variation and proved that laying sequence has an important effect on embryonic heart rate in Russet Sparrows.展开更多
Most proteins adopt an approximate structural symmetry. However, they have no symmetry detectable in their sequences and it is unclear for most of these proteins whether their structural symmetry originates from dupli...Most proteins adopt an approximate structural symmetry. However, they have no symmetry detectable in their sequences and it is unclear for most of these proteins whether their structural symmetry originates from duplication. As one of the six popular folds (super-folds) possessing an approximate structural symmetry, the triosephosphate isomerase barrel (TIM-barrel) domain has been widely studied. Using modified recurrent quantification analysis of primary sequences, we identified the same 2-, 3-, and 4-fold symmetry pattern as their tertiary structures. This result indicates that the symmetry in tertiary structure is coded by symmetry in the primary sequence and that the TIM-barrel adopts a 2-, 3-, or 4-fold repeat pattern during evolution. This discovery will be useful for understanding the evolutionary mechanisms of this protein family and the symmetry pattern that may be a clue into the ancient origin of duplication of half-barrels or the β a unit.展开更多
目的:探索磁共振成像多点非对称回波采集与迭代最小二乘法水脂分离(iterative decomposition of water and fat with echo asymmetry and the least squares estimation quantification sequence,IDEAL-IQ)和体素内不相干运动(intravoxe...目的:探索磁共振成像多点非对称回波采集与迭代最小二乘法水脂分离(iterative decomposition of water and fat with echo asymmetry and the least squares estimation quantification sequence,IDEAL-IQ)和体素内不相干运动(intravoxel incoherent motion,IVIM)在子宫内膜癌(endometrial carcinoma,EC)细胞增殖状态评估中的价值。方法:回顾并分析24例Ki-67增殖指数低(≤50%)和19例Ki-67增殖指数高(>50%)的EC患者的资料,分别测量病灶IDEAL-IQ成像的脂肪分数(fat fraction,FF)、R_(2)^(*)弛豫率(R_(2)^(*))值和IVIM成像的慢速表观弥散系数(slow apparent diffusion coefficient,ADCslow)、快速表观弥散系数(fast apparent diffusion coefficient,ADC-fast)和灌注分数(perfusion fraction,f)并进行对比。受试者工作特征(receiver operating characteristic,ROC)曲线的曲线下面积(area under curve,AUC)被用于确定各参数的诊断效能,logistic回归和DeLong检验分别被用于多参数联合诊断和不同AUC间的差异分析。Spearman相关被用于评估各参数值与Ki-67增殖指数的相关性。结果:Ki-67增殖指数高的组ADC-slow、ADC-fast和R_(2)^(*)值均显著低于Ki-67增殖指数低的组(P分别为<0.001、0.004、<0.001)。ADC-slow、ADC-fast、R_(2)^(*)以及三者联合鉴别Ki-67增殖指数高、低组EC的AUC分别为0.860、0.748、0.862和0.978。DeLong分析显示,ADC-slow+ADC-fast+R_(2)^(*)与ADC-slow、ADC-fast及R_(2)^(*)之间的AUC差异均有统计学意义(Z分别为2.109、3.134、2.227;P分别为0.035、0.002、0.023)。ADC-slow和R_(2)^(*)值均与Ki-67增殖指数呈中度负相关(r分别为-0.547、-0.711,P<0.001),ADC-fast与Ki-67增殖指数呈轻度负相关(r分别为-0.324,P=0.034)。结论:ADC-slow、ADC-fast和R_(2)^(*)均有助于评估EC患者的细胞增殖状态,且三者联合能够对Ki-67增殖指数高、低组EC进行更有效的鉴别。展开更多
旨在通过对崇仁麻鸡背部皮肤毛囊组织的转录组学分析,筛选关键的差异表达基因和信号通路,探讨鸡皮肤毛囊性状的分子调控机制。采用TRIzol法提取皮肤毛囊组织总RNA,通过Illumina平台进行转录组高通量测序(RNA-Seq)。最后采用实时荧光定...旨在通过对崇仁麻鸡背部皮肤毛囊组织的转录组学分析,筛选关键的差异表达基因和信号通路,探讨鸡皮肤毛囊性状的分子调控机制。采用TRIzol法提取皮肤毛囊组织总RNA,通过Illumina平台进行转录组高通量测序(RNA-Seq)。最后采用实时荧光定量的方法对转录组测序进行验证。研究结果如下:共筛选出了3856个差异表达基因,在公鸡(BGB vs YGB)比较组合中筛选出了971个差异表达基因,其中274个表达上调,697个表达下调。在母鸡(BMB vs YMB)比较组合中筛选出了3529个差异表达基因,其中1477个上调,2052个下调。在公鸡、母鸡共同的差异表达基因中筛选出了3个与皮肤毛囊性状有关的高表达基因KRT75、KRT6A和KRT14。在GO功能显著富集中,BGB vs YGB比较组合富集到了516个GO term,BMB vs YMB比较组合富集到了1020个GO term,基因主要集中参与细胞黏附等活动。显著富集了多条KEGG通路,在BGB vs YGB比较组合中富集了8条显著的KEGG通路,在BMB vs YMB比较组合中富集了20条显著的KEGG通路,筛选出了3条关键通路Wnt信号传导途径、神经活性配体-受体调控通路和TGF-β调控通路。荧光定量结果显示,随机选取的5个差异基因在皮肤毛囊中的表达与RNA-Seq走向趋势一致。综上所述,筛选的KRT75、KRT6A、KRT14基因可能影响鸡皮肤毛囊性状;神经活性配体-受体调控通路、Wnt信号通路和TGF-β信号通路均是调控鸡皮肤毛囊性状的重要通路。展开更多
目的探讨ID4、ZO-1基因甲基化定量检测作为基因标志在急性白血病（acute leukemia，AL）中的意义。方法采用硫化测序PCR（bisulfite sequencing PCR，BSP）法及甲基化特异性PCR（methylightion specific PCR，MSP）法检测AL中NB4细胞和...目的探讨ID4、ZO-1基因甲基化定量检测作为基因标志在急性白血病（acute leukemia，AL）中的意义。方法采用硫化测序PCR（bisulfite sequencing PCR，BSP）法及甲基化特异性PCR（methylightion specific PCR，MSP）法检测AL中NB4细胞和健康供者骨髓（normal bone marrow，NBM）细胞的ID4、ZO-1基因的甲基化状况并进行分析。结果BSP法检测ID4基因在ALNB4细胞中甲基化阳性率为86．0％，显著高于NBM细胞甲基化阳性率（4．8％），差异有统计学意义（P〈0．05）；ZO-1基因在ALNB4细胞系中甲基化阳性率为88．4％，显著高于NBM细胞甲基化阳性率（1．9％），差异有统计学意义（PP〈0．05）。采用MsP法检测9种AL细胞系，ID4、ZO-1基因甲基化水平在淋系来源的细胞系高于髓系来源的细胞系。结论ID4、ZO-1基因甲基化水平检测可作为新的AL基因标志物。展开更多
基金Supported by National Natural Science Foundation of China,No.82272053.
文摘BACKGROUND Iterative decomposition of water and fat with echo asymmetry and least squares estimation quantification sequence(IDEAL-IQ)is based on chemical shift-based water and fat separation technique to get proton density fat fraction.Multiple studies have shown that using IDEAL-IQ to test the stability and repeatability of liver fat is acceptable and has high accuracy.AIM To explore whether Gadoxetate Disodium(Gd-EOB-DTPA)interferes with the measurement of the hepatic fat content quantified with the IDEAL-IQ and to evaluate the robustness of this technique.METHODS IDEAL-IQ was used to quantify the liver fat content at 3.0T in 65 patients injected with Gd-EOB-DTPA contrast.After injection,IDEAL-IQ was estimated four times,and the fat fraction(FF)and R2* were measured at the following time points:Precontrast,between the portal phase(70 s)and the late phase(180 s),the delayed phase(5 min)and the hepatobiliary phase(20 min).One-way repeated-measures analysis was conducted to evaluate the difference in the FFs between the four time points.Bland-Altman plots were adopted to assess the FF changes before and after injection of the contrast agent.P<0.05 was considered statistically significant.RESULTS The assessment of the FF at the four time points in the liver,spleen and spine showed no significant differences,and the measurements of hepatic FF yielded good consistency between T1 and T2[95%confidence interval:-0.6768%,0.6658%],T1 and T3(-0.3900%,0.3178%),and T1 and T4(-0.3750%,0.2825%).R2* of the liver,spleen and spine increased significantly after injection(P<0.0001).CONCLUSION Using the IDEAL-IQ sequence to measure the FF,we can obtain results that will not be affected by Gd-EOB-DTPA.The high reproducibility of the IDEAL-IQ sequence makes it available in the scanning interval to save time during multiphase examinations.
基金supported by the National Natural Science Foundation of China(No.31672303 to CY,and 31772453 to WL)
文摘Background: Laying sequence has important effects on eggshell color and embryonic development in birds. Some birds can allocate resources unevenly among the eggs within a clutch, prioritizing those at the beginning of the laying sequence, in order to maximize reproductive success. The changes in egg color according to laying sequence may be an adaptation to pressure from predators or brood parasites.Methods: In this study, effects of laying sequence on egg color and embryonic heart rate in Russet Sparrows(Passer cinnamomeus) were investigated using artificial nest boxes. The eggs were divided into three groups: first to be laid, intermediate in the laying sequence, and last to be laid. We maintained the eggs in an incubator and measured embryonic heart rates.Results: Avian visual modeling showed that the background color brightness of the last eggs laid was significantly higher(whiter) than those of the other eggs. All eggs were about the same size and hatched around 13 days, indicating that laying sequence significantly affected embryonic development speed; the last eggs to be laid developed significantly faster than did the first in the clutch.Conclusions: Our study quantified the effect of laying sequence on egg color variation and proved that laying sequence has an important effect on embryonic heart rate in Russet Sparrows.
文摘Most proteins adopt an approximate structural symmetry. However, they have no symmetry detectable in their sequences and it is unclear for most of these proteins whether their structural symmetry originates from duplication. As one of the six popular folds (super-folds) possessing an approximate structural symmetry, the triosephosphate isomerase barrel (TIM-barrel) domain has been widely studied. Using modified recurrent quantification analysis of primary sequences, we identified the same 2-, 3-, and 4-fold symmetry pattern as their tertiary structures. This result indicates that the symmetry in tertiary structure is coded by symmetry in the primary sequence and that the TIM-barrel adopts a 2-, 3-, or 4-fold repeat pattern during evolution. This discovery will be useful for understanding the evolutionary mechanisms of this protein family and the symmetry pattern that may be a clue into the ancient origin of duplication of half-barrels or the β a unit.
文摘目的:探索磁共振成像多点非对称回波采集与迭代最小二乘法水脂分离(iterative decomposition of water and fat with echo asymmetry and the least squares estimation quantification sequence,IDEAL-IQ)和体素内不相干运动(intravoxel incoherent motion,IVIM)在子宫内膜癌(endometrial carcinoma,EC)细胞增殖状态评估中的价值。方法:回顾并分析24例Ki-67增殖指数低(≤50%)和19例Ki-67增殖指数高(>50%)的EC患者的资料,分别测量病灶IDEAL-IQ成像的脂肪分数(fat fraction,FF)、R_(2)^(*)弛豫率(R_(2)^(*))值和IVIM成像的慢速表观弥散系数(slow apparent diffusion coefficient,ADCslow)、快速表观弥散系数(fast apparent diffusion coefficient,ADC-fast)和灌注分数(perfusion fraction,f)并进行对比。受试者工作特征(receiver operating characteristic,ROC)曲线的曲线下面积(area under curve,AUC)被用于确定各参数的诊断效能,logistic回归和DeLong检验分别被用于多参数联合诊断和不同AUC间的差异分析。Spearman相关被用于评估各参数值与Ki-67增殖指数的相关性。结果:Ki-67增殖指数高的组ADC-slow、ADC-fast和R_(2)^(*)值均显著低于Ki-67增殖指数低的组(P分别为<0.001、0.004、<0.001)。ADC-slow、ADC-fast、R_(2)^(*)以及三者联合鉴别Ki-67增殖指数高、低组EC的AUC分别为0.860、0.748、0.862和0.978。DeLong分析显示,ADC-slow+ADC-fast+R_(2)^(*)与ADC-slow、ADC-fast及R_(2)^(*)之间的AUC差异均有统计学意义(Z分别为2.109、3.134、2.227;P分别为0.035、0.002、0.023)。ADC-slow和R_(2)^(*)值均与Ki-67增殖指数呈中度负相关(r分别为-0.547、-0.711,P<0.001),ADC-fast与Ki-67增殖指数呈轻度负相关(r分别为-0.324,P=0.034)。结论:ADC-slow、ADC-fast和R_(2)^(*)均有助于评估EC患者的细胞增殖状态,且三者联合能够对Ki-67增殖指数高、低组EC进行更有效的鉴别。
文摘旨在通过对崇仁麻鸡背部皮肤毛囊组织的转录组学分析,筛选关键的差异表达基因和信号通路,探讨鸡皮肤毛囊性状的分子调控机制。采用TRIzol法提取皮肤毛囊组织总RNA,通过Illumina平台进行转录组高通量测序(RNA-Seq)。最后采用实时荧光定量的方法对转录组测序进行验证。研究结果如下:共筛选出了3856个差异表达基因,在公鸡(BGB vs YGB)比较组合中筛选出了971个差异表达基因,其中274个表达上调,697个表达下调。在母鸡(BMB vs YMB)比较组合中筛选出了3529个差异表达基因,其中1477个上调,2052个下调。在公鸡、母鸡共同的差异表达基因中筛选出了3个与皮肤毛囊性状有关的高表达基因KRT75、KRT6A和KRT14。在GO功能显著富集中,BGB vs YGB比较组合富集到了516个GO term,BMB vs YMB比较组合富集到了1020个GO term,基因主要集中参与细胞黏附等活动。显著富集了多条KEGG通路,在BGB vs YGB比较组合中富集了8条显著的KEGG通路,在BMB vs YMB比较组合中富集了20条显著的KEGG通路,筛选出了3条关键通路Wnt信号传导途径、神经活性配体-受体调控通路和TGF-β调控通路。荧光定量结果显示,随机选取的5个差异基因在皮肤毛囊中的表达与RNA-Seq走向趋势一致。综上所述,筛选的KRT75、KRT6A、KRT14基因可能影响鸡皮肤毛囊性状;神经活性配体-受体调控通路、Wnt信号通路和TGF-β信号通路均是调控鸡皮肤毛囊性状的重要通路。
文摘目的探讨ID4、ZO-1基因甲基化定量检测作为基因标志在急性白血病（acute leukemia，AL）中的意义。方法采用硫化测序PCR（bisulfite sequencing PCR，BSP）法及甲基化特异性PCR（methylightion specific PCR，MSP）法检测AL中NB4细胞和健康供者骨髓（normal bone marrow，NBM）细胞的ID4、ZO-1基因的甲基化状况并进行分析。结果BSP法检测ID4基因在ALNB4细胞中甲基化阳性率为86．0％，显著高于NBM细胞甲基化阳性率（4．8％），差异有统计学意义（P〈0．05）；ZO-1基因在ALNB4细胞系中甲基化阳性率为88．4％，显著高于NBM细胞甲基化阳性率（1．9％），差异有统计学意义（PP〈0．05）。采用MsP法检测9种AL细胞系，ID4、ZO-1基因甲基化水平在淋系来源的细胞系高于髓系来源的细胞系。结论ID4、ZO-1基因甲基化水平检测可作为新的AL基因标志物。
