改良V-Y外眦开大成形术的临床应用

目的：探讨改良V-Y外眦开大成形新术式。方法：将Y形切口线设计在睑缘灰线，板层劈开上下睑，并在切口末端增加两条垂直于睑缘的辅助切口线，切开睑板及睑结膜；部分或完全切断外眦韧带，充分分离使外眦呈“游离状态”。在无张或微张力的情况下外移外眦。结果：102例外眦开大成形术99例达到预期效果，开大外眦达1．5～5mm。结论：改良V-Y外眦开大成形术相比传统手术，保留了外眦外形结构，术后外眦无变形，远期回缩轻微，是目前比较理想的合乎美学原理的外眦开大成形术式。     

Frontal and subcortical contribution to visual hallucinations in dementia with Lewy bodies and Parkinson’s disease

Objectives: Visual hallucinations (VH) are common in Lewy body disease (LBD), and have been associated with cognitive and structural brain alterations. Evidence so far concerns mainly Parkinson’s disease (PD), but little is known about symptom-specific pathophysiological mechanisms across the LBD spectrum, especially related to the presence of dementia. The aim of the present pilot study was to investigate the neuroanatomical, and neuropsychological characteristics related to VH in two forms of LBD, namely dementia with Lewy bodies (DLB) and PD without dementia.

Methods: Whole brain voxel-based morphometry (VBM) analyses on 3D MRI acquired structural brain scans, and neuropsychological testing were performed on 28 clinically diagnosed DLB (11 with VH, 17 NVH), and 24 PD (9 with VH, and 15 NVH) patients. In order to assess differences in gray matter (GM) regional volumes, and cognitive performance, hallucinating patients for each group were compared with corresponding non-hallucinating ones.

Results: DLB patients with VH presented significantly worse visual attention deficits compared to those without, which persisted even when controlling for visual perception. Whole brain VBM analysis revealed decreased GM volume in DLB with VH in the right superior and medial frontal gyri, putamen, caudate nucleus and insula. Subcortical regional volumes were also significantly associated with visual attention performance. Hallucinating PD patients, instead, presented more severe executive dysfunction, but VBM showed no volumetric differences between the two PD subgroups. Post hoc region of interest analyses revealed striatal GM loss in PD with VH.

Conclusion: Frontal and striatal GM atrophy may contribute to the emergence of VH in DLB, which may be fostered by the more severe attention deficits. Striatal GM loss and executive dysfunction, instead, appeared to underlie VH in PD without dementia.     

Prostate volume as an independent predictor of prostate cancer in men with PSA of 10–50?ng ml?1

Prostate volume (PV) has been shown to be associated with prostate cancer (PCa) detection rates in men with a prostate-specific antigen (PSA) in the ‘grey zone'' (2.0–10.0 ng ml⁻¹). However, the PSA ‘grey zone'' in Asian men should be higher because the incidence of PCa in Asian men is relatively low. Therefore, we evaluated the association between PV and PCa detection rates in men with PSAs measuring 10–50 ng ml⁻¹. Men who underwent a 13-core prostatic biopsy with PV documentation participated in the study. A multivariate stepwise regression was used to evaluate whether the PV at time of prostate biopsy could predict the risk of PCa. The rates of PCa among men in different PSA ranges, stratified by PV medians (<60 and ≥60 ml), were calculated. There were 261 men included in the final analysis. PV was the strongest predictor of PCa risk (odds ratio, 0.02; P<0.001) compared to other variables. The PCa rates in men with PVs measuring <60 and ≥60 ml in the 10–19.9 ng ml⁻¹ PSA group were 40.6% and 15.1%, respectively, while the rates for men with PSAs measuring 20–50 ng ml⁻¹ were 65.1% and 26.8%. PV is an independent predictor of PCa in men with PSA measuring 10–50 ng ml⁻¹. In clinical practice, particularly for those countries with lower incidences of PCa, PV should be considered when counselling patients with PSAs measuring 10–50 ng ml⁻¹ regarding their PCa risks.     

Inversion recovery ultrashort echo time imaging of ultrashort T2 tissue components in ovine brain at 3 T: a sequential D2O exchange study

Inversion recovery ultrashort echo time (IR‐UTE) imaging holds the potential to directly characterize MR signals from ultrashort T₂ tissue components (STCs), such as collagen in cartilage and myelin in brain. The application of IR‐UTE for myelin imaging has been challenging because of the high water content in brain and the possibility that the ultrashort T₂* signals are contaminated by water protons, including those associated with myelin sheaths. This study investigated such a possibility in an ovine brain D₂O exchange model and explored the potential of IR‐UTE imaging for the quantification of ultrashort T₂* signals in both white and gray matter at 3 T. Six specimens were examined before and after sequential immersion in 99.9% D₂O. Long T₂ MR signals were measured using a clinical proton density‐weighted fast spin echo (PD‐FSE) sequence. IR‐UTE images were first acquired with different inversion times to determine the optimal inversion time to null the long T₂ signals (TI_null). Then, at this TI_null, images with echo times (TEs) of 0.01–4 ms were acquired to measure the T₂* values of STCs. The PD‐FSE signal dropped to near zero after 24 h of immersion in D₂O. A wide range of TI_null values were used at different time points (240–330 ms for white matter and 320–350 ms for gray matter at TR = 1000 ms) because the T₁ values of the long T₂ tissue components changed significantly. The T₂* values of STCs were 200–300 μs in both white and gray matter (comparable with the values obtained from myelin powder and its mixture with D₂O or H₂O), and showed minimal changes after sequential immersion. The ultrashort T₂* signals seen on IR‐UTE images are unlikely to be from water protons as they are exchangeable with deuterons in D₂O. The source is more likely to be myelin itself in white matter, and might also be associated with other membranous structures in gray matter.     

PSA灰区值时MRI+MRS在早期诊断前列腺癌中临床意义

目的：探讨PSA 灰区值时，MRI+MRS 在早期诊断前列腺癌中临床意义。方法对92例PSA4-10ng/ml 患者行MRI+MRS检查，对MRI 异常和（或）MRS 检查(胆碱+肌酸)/枸橼酸盐(Cho+Cre/Cit)≥0.75患者进行前列腺穿刺活检，MRI+MRS无异常者，有手术指征行前列腺电切术，术后行病理检查，无手术指征定期随访。结果73例MRI异常和（或）Cho+Cre/Cit≥0.75穿刺后，12例前列腺癌，其中1例前列腺癌患者MRI示前列腺肿瘤已侵及前列腺包膜，19例MRI+MRS无异常者术后病理1例前列腺癌。阳性组(前列腺癌组）Cho+Cre/Cit值与阴性组（前列腺增生）相比差异显著（P＜0.05)。结论 PSA4-10ng/ml前列腺增生患者，常规行MRI+MRS，有助于前列腺癌早期诊断及临床分期，以Cho+Cre/Cit≥1.29为穿刺的最佳临界值，但有待大样本研究进一步证实及界定。     

Relation between plasma trough concentration of abiraterone and prostate-specific antigen response in metastatic castration-resistant prostate cancer patients

BackgroundAbiraterone (ABI) is a major oral agent for the treatment of metastatic castration-resistant prostate cancer (mCRPC) patients but its systemic exposure is subject to a large inter-individual variability. We aimed to explore the relationship between ABI trough plasma concentration and prostate-specific antigen (PSA) response in mCRPC patients and to identify the critical determinants for its activity.Patients and methodsThis is a monocentric prospective observational study in mCRPC patients treated with ABI. The plasmatic concentration of ABI at steady state was measured using liquid chromatography with fluorescence detection. The primary objective was to study the relationship between mean ABI plasma exposure (ABI C_min) and 3-month PSA response.ResultsFrom 2012 to 2016, 61 mCRPC patients were eligible for pharmacokinetic/pharmacodynamic assessment. Thirty-eight patients experienced PSA response (62%, [confidence interval {CI} 95% 50–78]). In univariate analysis, ABI C_min was 1.5-fold higher in responders: 12.0 ng/mL (CI 95% 9.4–15.6) versus 8.0 ng/mL (CI 95% 5.8–11.6; P = 0.0015). In multivariate analysis, only ABI C_min was independently associated with PSA response (odds ratio = 1.12 [CI 95% 1.01–1.25], P = 0.004). By receiver operating characteristic analysis, the optimal threshold for ABI C_min was 8.4 ng/mL. Progression-free survival (PFS) was significantly higher in patients with ABI C_min above 8.4 ng/mL (hazard ratio 0.55, [CI 95% 0.31–0.99], 12.2 [CI 95% 9.2–19.5] versus 7.4 [CI 95% 5.5–14.7] months otherwise, P = 0.044).ConclusionsWe showed that ABI trough concentration correlates with PSA response and PFS. Moreover, we could determine a cut-off value of plasmatic concentration for PSA response. Altogether, ABI concentration monitoring appears as a new approach to improve clinical outcome in mCPRC patients.     

分子筛制氧机富氧气体组分分析

[摘要】目的：通过对分子筛制氧机富氧气体进行组分分析，为改进变压吸附工艺或研发新型分子筛材料以获取高纯氧奠定基础。方法：采用气相色谱分析仪，测试分子筛制氧机富氧气体的氧气、氮气、氩气、二氧化碳、总烃的含量。结果：分子筛制氧机富氧气体的主要杂质为氮气和氩气，二氧化碳和总烃含量微小。随着氧气含量增加，氮气含量降低，氩气含量增加。当氧气体积分数为94．4249％时，氩气体积分数为5．1101％，氮气体积分数仅为0．4643％。结论：影响分子筛制氧机制备的富氧气体氧含量的主要因素为空气中的氩气，常用的沸石分子筛很难吸附分离氩气，需要研发具有氧、氩分离性能的新型分子筛材料以获取高纯度氧气。     

Ready for action: a role for the human midbrain in responding to infant vocalizations

Infant vocalizations are among the most biologically salient sounds in the environment and can draw the listener to the infant rapidly in both times of distress and joy. A region of the midbrain, the periaqueductal gray (PAG), has long been implicated in the control of urgent, survival-related behaviours. To test for PAG involvement in the processing of infant vocalizations, we recorded local field potentials from macroelectrodes implanted in this region in four adults who had undergone deep brain stimulation. We found a significant difference occurring as early as 49 ms after hearing a sound in activity recorded from the PAG in response to infant vocalizations compared with constructed control sounds and adult and animal affective vocalizations. This difference was not present in recordings from thalamic electrodes implanted in three of the patients. Time frequency analyses revealed distinct patterns of activity in the PAG for infant vocalisations, constructed control sounds and adult and animal vocalisations. These results suggest that human infant vocalizations can be discriminated from other emotional or acoustically similar sounds early in the auditory pathway. We propose that this specific, rapid activity in response to infant vocalizations may reflect the initiation of a state of heightened alertness necessary to instigate protective caregiving.