Imaging apolipoprotein AI in vivo

Coronary disease risk increases inversely with high-density lipoprotein (HDL) level. The measurement of the biodistribution and clearance of HDL in vivo, however, has posed a technical challenge. This study presents an approach to the development of a lipoprotein MRI agent by linking gadolinium methanethiosulfonate (Gd[MTS-ADO3A]) to a selective cysteine mutation in position 55 of apo AI, the major protein of HDL. The contrast agent targets both liver and kidney, the sites of HDL catabolism, whereas the standard MRI contrast agent, gadolinium-diethylenetriaminepentaacetic acid-bismethylamide (GdDTPA-BMA, gadodiamide), enhances only the kidney image. Using a modified apolipoprotein AI to create an HDL contrast agent provides a new approach to investigate HDL biodistribution, metabolism and regulation in vivo.     

Quantitative MRI of the temporal lobe,amygdala, and hippocampus in normal human development: Ages 4–18 years

The volume of the temporal lobe, superior temporal gyrus, amygdala, and hippocampus was quantified from magnetic images of the brains of 99 healthy children and adolescents aged 4–18 years. Variability in volume was high for all structures examined. When adjusted for a 9% larger total cerebral volume in males, there were no significant volume differences between sexes. However, sex-specific maturational changes were noted in the volumes of medial temporal structures, with the left amygdala increasing significantly only in males and with the right hippocampus increasing significantly only in females. Right-greater-than-left laterality effects were found for temporal lobe, superior temporal gyrus, amygdala, and hippocampal volumes. These results are consistent with previous preclinical and human studies that have indicated hormonal responsivity of these structures and extend quantitative morphologic findings from the adult literature. In addition to highlighting the need for large samples and sex-matched controls in pediatric neuroimaging studies, the information from this understudied age group may be of use in evaluating developmental hypotheses of neuropsychiatric disorders. © 1996 Wiley-Liss, Inc.

1 This article is a US Government work and, as such, is in the public domain in the United States of America.

     

Cancer: A reproductive strategy of "ultra-selfish" genes?

A hypothesis is presented in which the process of "malignant transformation" which ultimately results in the rapidly dividing tumor(s)(cells) causing "cancer", is regarded as an evolved reproductive strategy of "ultra-selfish" (proto-)(onco-)genes, already present in the genome, or introduced by a virus.     

酶联免疫吸附试验中HBsAg室内质控参考品的制备和应用

目的建立室内质控参考品以鉴别诊断试剂的质量和控制操作误差,提高乙型肝炎病毒表面抗原的检测准确度。方法以国家标准品为标准制备灵敏度系列参考品、特异性参考品及精密性参考品。检测其稳定性,并进行同厂家、不同批号试剂的比较及不同厂家、三批试剂的比较。结果制备的室内质控参考品在-20℃与4℃保存3～4周检测结果无统计学差异。采用同一厂家、不同批号的HBsAg诊断试剂检测室内质控参考品,结果无统计学差异。采用不同厂家、同一批号的HBsAg诊断试剂检测结果有统计学差异。结论我们建立的室内质控参考品适宜作HBsAg室内质控,提醒我们在更换试剂厂家时应特别注意室内质控参考品的变化。