Neuroplasticity and cellular resilience in bipolar disorder

Manji HK, Zhou R, Chen G. Neuroplasticity and cellular resilience in bipolar disorder. Bipolar Disord 2002: 4(Suppl. 1): 56–57. © Blackwell Munksgaard, 2002     

A genome-wide association scan on estrogen receptor-negative breast cancer

Introduction

Breast cancer is a heterogeneous disease and may be characterized on the basis of whether estrogen receptors (ER) are expressed in the tumour cells. ER status of breast cancer is important clinically, and is used both as a prognostic indicator and treatment predictor. In this study, we focused on identifying genetic markers associated with ER-negative breast cancer risk.

Methods

We conducted a genome-wide association analysis of 285,984 single nucleotide polymorphisms (SNPs) genotyped in 617 ER-negative breast cancer cases and 4,583 controls. We also conducted a genome-wide pathway analysis on the discovery dataset using permutation-based tests on pre-defined pathways. The extent of shared polygenic variation between ER-negative and ER-positive breast cancers was assessed by relating risk scores, derived using ER-positive breast cancer samples, to disease state in independent, ER-negative breast cancer cases.

Results

Association with ER-negative breast cancer was not validated for any of the five most strongly associated SNPs followed up in independent studies (1,011 ER-negative breast cancer cases, 7,604 controls). However, an excess of small P-values for SNPs with known regulatory functions in cancer-related pathways was found (global P = 0.052). We found no evidence to suggest that ER-negative breast cancer shares a polygenic basis to disease with ER-positive breast cancer.

Conclusions

ER-negative breast cancer is a distinct breast cancer subtype that merits independent analyses. Given the clinical importance of this phenotype and the likelihood that genetic effect sizes are small, greater sample sizes and further studies are required to understand the etiology of ER-negative breast cancers.     

多层螺旋CT评价先天性单冠状动脉畸形

目的 探讨16层螺旋CT（MSCT）冠状动脉造影诊断先天性单冠状动脉畸形的价值。资料与方法 回顾性分析4例先天性单冠状动脉患者的MSCT和常规X线冠状动脉造影（CCA）资料。对比两者在显示和诊断此病中的差异。仿真内镜技术用于评价异位开口及其与邻近正常冠状动脉开口的关系,多平面重建、曲面多平面重建、最大密度投影、容积成像等重建方法则用于评价变异冠状动脉的行径及其与邻近大血管的关系。结果 4例患者变异的冠状动脉全部为MSCT造影所显示并明确诊断。MSCT显示3例患者的左主干起源于右冠状动脉的近段,其中1例在CCA中左主干仅近段局部显影,未能明确诊断,另2例左冠状动脉虽显影,但较淡。1例右冠状动脉起源于左主干的末端,CCA则误为起源于回旋支。MSCT显示2例异常开口冠状动脉的近段狭窄,3支异常冠状动脉穿过主动脉根部和肺动脉或右室流出道的间隙,1支绕主动脉根部后方走行,而CCA均不能明确诊断。结论 MSCT显示先天性单冠状动脉明显优于CCA,凡疑及冠状动脉变异的患者,可首选非创伤性的MSCT冠状动脉造影检查。     

The influence of flexed-knee gait on the energy cost of walking in children

There is ah understanding that walking with flexed knees contributes to the increased energy cost of walking found in children with neurological conditions. To determine the influence of flexed-knee gait on energy cost of walking in a group of children without neurological abnormality, the gait patterns of 10 normal children were studied using a Vicon system and standard marker set. A telemetric system (Cosmed K2) was then used to measure the oxygen cost of walking of the same children. The tests were repeated restricting the subjects' knee extension bilaterally, using hinged braces, set to 0, 15, 30, and 45° of flexion. Although the braces themselves caused a significant increase in O₂ cost (mL/kg/m) (P<0.05), due to a decrease in walking speed, no further significant increase in oxygen cost was demonstrated regardless of the degree of knee flexion imposed, despite a significant increase in measured hip flexion and ankle dorsiflexion at the 45° of knee flexion setting (P<0.05). We propose that moderate flexed-knee gait does not of itself cause an increase in the energy cost of walking and that other factors present in the physically disabled child are likely to be implicated.     

CO2 measurements during transcranial Doppler examinations in headache patients: methodological considerations

Transcranial Doppler (TCD) examinations are increasingly being used in studies of headache pathophysiology. Because blood velocity is highly dependent on pCO₂, these parameters should be measured simultaneously. The most common way of performing measurements during TCD examinations is as end-tidal pCO₂ witch a capnograph. When patients are nauseated and vomit, as in migraine, the mask or mouthpiece connected to the capnograph represents a problem. We therefore evaluated whether a transcutaneous pCO₂ electrode was as useful as the capnograph for pCO₂ measurements in TCD examinations. We conclude that this is not the case, and recommend capnographic end-tidal pCO₂ measurements during TCD examinations. However, transcutaneous pCO₂ measurements may represent a supplement to spot measurements of end-tidal pCO₂ in stable conditions when long-term monitoring is needed, and the mask or mouthpiece of the capnograph has to be taken on and off between recordings.