Diffusion‐weighted hyperpolarized 129Xe MRI in healthy volunteers and subjects with chronic obstructive pulmonary disease

Given its greater availability and lower cost, ¹²⁹Xe apparent diffusion coefficient (ADC) MRI offers an alternative to ³He ADC MRI. To demonstrate the feasibility of hyperpolarized ¹²⁹Xe ADC MRI, we present results from healthy volunteers (HV), chronic obstructive pulmonary disease (COPD) subjects, and age‐matched healthy controls (AMC). The mean parenchymal ADC was 0.036 ± 0.003 cm² sec^?1 for HV, 0.043 ± 0.006 cm² sec^?1 for AMC, and 0.056 ± 0.008 cm² sec^?1 for COPD subjects with emphysema. In healthy individuals, but not the COPD group, ADC decreased significantly in the anterior–posterior direction by ～22% (P = 0.006, AMC; 0.0059, HV), likely because of gravity‐induced tissue compression. The COPD group exhibited a significantly larger superior–inferior ADC reduction (～28%) than the healthy groups (～24%) (P = 0.00018, HV; P = 3.45 × 10^?5, AMC), consistent with smoking‐related tissue destruction in the superior lung. Superior–inferior gradients in healthy subjects may result from regional differences in xenon concentration. ADC was significantly correlated with pulmonary function tests (forced expiratory volume in 1 sec, r = ?0.77, P = 0.0002; forced expiratory volume in 1 sec/forced vital capacity, r = ?0.77, P = 0.0002; diffusing capacity of carbon monoxide in the lung/alveolar volume (V_A), r = ?0.77, P = 0.0002). In healthy groups, ADC increased with age by 0.0002 cm² sec^?1 year^?1 (r = 0.56, P = 0.02). This study shows that ¹²⁹Xe ADC MRI is clinically feasible, sufficiently sensitive to distinguish HV from subjects with emphysema, and detects age‐ and posture‐dependent changes. Magn Reson Med, 2010. © 2010 Wiley‐Liss, Inc.     

Hyperpolarized Xe MRI: A viable functional lung imaging modality?

The majority of researchers investigating hyperpolarized gas MRI as a candidate functional lung imaging modality have used (3)He as their imaging agent of choice rather than (129)Xe. This preference has been predominantly due to, (3)He providing stronger signals due to higher levels of polarization and higher gyromagnetic ratio, as well as its being easily available to more researchers due to availability of polarizers (USA) or ease of gas transport (Europe). Most researchers agree, however, that hyperpolarized (129)Xe will ultimately emerge as the imaging agent of choice due to its unlimited supply in nature and its falling cost. Our recent polarizer technology delivers vast improvements in hyperpolarized (129)Xe output. Using this polarizer, we have demonstrated the unique property of xenon to measure alveolar surface area noninvasively. In this article, we describe our human protocols and their safety, and our results for the measurement of the partial pressure of pulmonary oxygen (pO(2)) by observation of (129)Xe signal decay. We note that the measurement of pO(2) by observation of (129)Xe signal decay is more complex than that for (3)He because of an additional signal loss mechanism due to interphase diffusion of (129)Xe from alveolar gas spaces to septal tissue. This results in measurements of an equivalent pO(2) that accounts for both traditional T(1) decay from pO(2) and that from interphase diffusion. We also provide an update on new technological advancements that form the foundation for an improved compact design polarizer as well as improvements that provide another order-of-magnitude scale-up in xenon polarizer output.     

The human prion gene M129V polymorphism is not associated with idiopathic Parkinson's disease in three distinct populations

Coexistence of prion disease and idiopathic Parkinson's disease (IPD) has been previously described. It remains unclear whether this relationship may reflect the high incidence of IPD or whether both prion and IPD share common pathogenetic mechanisms. For this reason, we investigated the genotype distribution of the M129V polymorphism of the human prion gene for association with IPD (controls: n = 398, IPD cases: n = 400). No association between genotypes in codon 129 and IPD was detected in three distinct populations, suggesting that this PRNP polymorphism has no direct influence on the susceptibility to IPD.     

用等位基因组特异性引物扩增技术确认HLA-B新等位基因B*15:129

目的 对人类白细胞抗原(human leukocyte antigen,HLA)新等位基因HLA-B*15:129的第2～4外显子序列进行分析.方法 采用商用抽提试剂盒抽提标本DNA,应用等位基因组特异性引物PCR方法扩增先证者标本HLA-B基因第2～4外显子,PCR产物经酶切纯化后直接进行HLA-B基因第2～4外显子双向测序分析.结果 先证者标本存在2个HLA-B等位基因,1个等位基因为B*07:02,另1个经Blast验证为新的等位基因,新的等位基因序列已递交GenBank(EF473219),经世界卫生组织HLA命名委员会正式命名为HLA-B*15:129.HLA-B*15:129第2～4外显子序列与最接近的B*15:01:01:01相比,第3外显子存在3个碱基的不同,即第362位G→A、363位G→T、369位C→T改变,导致第97位氨基酸Arg→Asn.结论 发现1例新的HLA-B等位基因,被世界卫生组织HLA基因命名委员会正式命名为HLA-B*15:129.

Abstract：

Objective To analyze the sequence of the exons 2-4 of human leukocyte antigen (HLA) novel allele HLA-B*15:129.Methods DNA of the proband was extracted from whole blood by commercial DNA extraction kit. The amplification for HLA-B exons 2-4 was performed separately by polymerase chain reaction (PCR) with allele group specific primers. The PCR products were digested with enzymes and then directly sequenced for exons 2-4 of HLA-B locus in both directions.Results Sequencing results showed the HLA-B alleles of the proband included B*07:02 and a novel allele. The sequence of the novel allele has been submitted to GenBank (accession no. EF473219) and the allele has been officially named B*15:129 by the WHO Nomenclature Committee. Comparing with the HLA-B*15:01:01:01, the sequence of exons 2-4 of HLA-B*15:129 showed three nucleotide difference in exon 3 at positions 362 and 363 from GG to AT and positions 369 from C to T, which resulted in an amino acid change from Arg to Asn at codon 97.Conclusion A novel HLA-B allele was identified and has been officially named B15:129 by the WHO Nomenclature Committee.     

过表达miR-129-5p通过靶向MAPK1抑制宫颈癌HeLa细胞恶性生物行为

[摘要] 目的：探讨miR-129-5p 对宫颈癌HeLa细胞侵袭、迁移和EMT的作用及其机制。方法：选取宫颈癌HeLa细胞,利用生物信息学预测软件筛选miR-129-5p 的靶基因,双荧光素酶报告基因验证miR-129-5p 和MAPK1 的靶向关系。将miR-129-5p mimic、miR-129-5p inhibitor 和pcDNA-MAPK1 单独或联合转染到HeLa细胞,用qPCR检测HeLa细胞中miR-129-5p 和MAPK1 的表达水平,用Transwell、划痕愈合实验分别检测HeLa 细胞的侵袭、迁移能力,WB检测细胞中E-cadherin、N-cadherin、MAPK1、STAT3 和Bcl-xL的表达。构建裸鼠HeLa细胞皮下移植瘤模型,观察miR-129-5p 过表达对移植瘤生长的影响,WB检测移植瘤组织中EMT及MAPK1 通路相关蛋白的表达。结果：miR-129-5p 与MAPK1 在3’UTR区存在结合位点,过表达miR-129-5p 靶向抑制MAPK1（P<0.01）。与对照组相比,miR-129-5p mimic 组侵袭细胞数目减少（P<0.01）,划痕愈合率降低（均P<0.01）;细胞中Ecadherin表达上调而N-cadherin、MAPK1、STAT3 和Bcl-xL 表达下调（均P<0.01）;共转染MAPK1 可逆转上述现象。成功建立裸鼠HeLa 细胞移植瘤模型,与对照组相比,miR-128-3p mimic 组肿瘤质量减轻（P<0.01）;瘤组织中E-cadherin 表达水平上调而N-cadherin、MAPK1、STAT3 和Bcl-xL 的表达下调（均P<0.01）。结论：过表达miR-129-5p 通过靶向MAPK1 抑制宫颈癌HeLa细胞的侵袭、迁移和EMT。