New tools for the control of peptide conformation: the helicogenic Cα‐methyl,Cα‐cyclohexylglycine*

Abstract: The novel C^α‐tetrasubstituted α‐amino acid C^α‐methyl, C^α‐cyclohexylglycine was prepared by hydrogenation of its C^α‐methyl, C^α‐phenylglycine precursor. Terminally protected homodi‐, homotri‐, and homotetrapeptides from C^α‐methyl, C^α‐cyclohexylglycine and co‐oligopeptides to the pentamer level in combination with Gly or α‐aminoisobutyric acid residues were prepared by solution methods and fully characterized. The results of a conformational analysis, performed by use of Fourier transform infrared (FT‐IR) spectrophotomet absorption, ¹H NMR, and X‐ray diffraction techniques, support the contention that this C^α‐methylated, C^β‐trisubstituted aliphatic α‐amino acid is an effective β‐turn and 3₁₀‐helix inducer in tri‐ and longer peptides as its C^α‐methyl valine parent compound, but partially divergent from the corresponding aromatic C^α‐methyl, C^α‐diphenylmethylglycine residue, known to promote folded and fully extended structures to a significant extent in these oligomers.     

Unexpected exit of a cochlear implant electrode through the wall of the basal turn of the cochlea — a report on two patients

Abstract

We describe the unusual complication of the cochlear implant electrode eroding through the lateral bony wall of the cochlear basal turn in 2 different patients. This complication, occurring during life, has not been previously described in the literature. Radiological investigations were vital in making this diagnosis. We also discuss the likely pathophysiology behind this complication. Copyright © 2007 John Wiley & Sons, Ltd.     

Evaluation of divided attention psychophysical task performance and effects on pupil sizes following smoked,vaporized and oral cannabis administration

Establishing science‐based driving per se blood Δ⁹‐tetrahydrocannabinol (THC) limits is challenging, in part because of prolonged THC detection in chronic, frequent users. Therefore, documenting observable signs of impairment is important for driving under the influence of drugs. We evaluated frequent and occasional cannabis smokers' performance on the modified Romberg balance, one leg stand (OLS), and walk and turn (WAT) tasks, and pupil size effects following controlled placebo (0.001% THC), smoked, vaporized and oral (6.9% [~50.4 mg] THC) cannabis administration. Significant effects following inhaled doses were not observed due to delayed tasks administration 1.5 and 3.5 h post‐dose, but significant impairment was observed after oral dosing (blood THC concentrations peaked 1.5–3.5 h post‐dose). Occasional smokers' odds of exhibiting ≥2 clues on the OLS or WAT following oral dosing were 6.4 (95% CI 2.3–18.4) times higher than after placebo, with THC and 11‐hydroxy‐THC blood concentrations individually producing odds ratios of 1.3 (1.1–1.5) and 1.5 (1.3–1.8) for impairment in these tasks, respectively. Pupil sizes after oral dosing under the direct lighting condition were significantly larger than after placebo by mean (SE, 95% CI) 0.4 (0.1, 0.2–0.6) mm at 1.5 h and 0.5 (0.2, 0.2–0.8) mm at 3.5 h among all participants. Oral cannabis administration impaired occasional cannabis users' performance on the OLS and WAT tasks compared to placebo, supporting other reports showing these tasks are sensitive to cannabis‐related impairment. Occasional smokers' impairment was related to blood THC and 11‐hydroxy‐THC concentrations. These are important public health policy findings as consumption of edible cannabis products increases. Published 2017. This article is a U.S. Government work and is in the public domain in the USA.     

6例伴肝功能损害卟啉病患者的临床特点分析

[摘要]?卟啉病是一种与血红素生物合成途径中酶活性缺乏有关的遗传代谢性疾病,其中以肝功能损害为表现的卟啉病较为罕见,易造成误诊、漏诊。我中心在2014年11月—2019年12月共收治6例伴有肝功能损害卟啉病患者,现对其临床表现、肝脏损伤指标、肝脏病理特征、基因检测结果、治疗及转归进行总结分析,以期提高临床医生对伴有肝功能损害卟啉病的认识。     

血浆替代血清行常规生化检测缩短正流转时间的可行性探讨

目的探讨肝素锂抗凝血浆替代血清进行常规生化检测缩短正流转时间(TAT)的可行性。方法应用日立H7600-20全自动生化分析仪对抽取的110例患者肝素锂抗凝血浆和血清中的35项生化检测结果进行比对分析。结果在肝素锂抗凝血浆与血清的35项生化检测结果中,清蛋白(ALB)、γ-谷氨酰基转移酶(GGT)、总胆汁酸(TBA)、总胆红素(TB)、氯(Cl)、钙(Ca)、镁(Mg)、肌酐(CRE)、尿素(BUN)、尿酸(UA)、胱抑素C(CysC)、β2-微球蛋白(β2-MG)、肌酸激酶(CK)、肌酸激酶同工酶(CK-MB)、乳酸脱氢酶(LDH)和高密度脂蛋白胆固醇(HDL-C)共16项指标的检测结果比较差异无统计学意义(P0.05);而钠离子(Na+)、钾离子(K+)、二氧化碳(CO2)、磷(P)、铁(Fe)、丙氨酸氨基转移酶(ALT)、天门冬氨酸氨基转移酶(AST)、碱性磷酸酶(ALP)、总蛋白(TP)、前清蛋白(PreA)、α-L-岩藻糖苷酶(AFU)、三酰甘油(TG)、总胆固醇(TCH)、低密度脂蛋白胆固醇(LDL-C)、载脂蛋白A1(ApoA1)、载脂蛋白B(ApoB)、脂蛋白a[Lp(a)]、血糖(GLU)、直接胆红素(DB)共19项指标的检测结果比较差异有统计学意义(P0.05)。结论肝素锂抗凝血浆与血清中常规生化检测结果不完全一致,肝素锂抗凝血浆可选择性地替代血清进行部分急诊生化检测以缩短TAT。     

鼻腔鼻窦内翻性乳头状瘤比较CT与MRI在诊断中的作用

【摘要】目的：分析鼻腔鼻窦内翻性乳头状瘤应用CT和MRI的诊断价值。方法：以102例病理检查确诊为鼻腔鼻窦内翻性乳头状瘤患者为研究对象,分别使用CT和MRI检查,对比CT和MRI检查结果与病理检查结果。结果：CT扫描可清晰显示NIP边界、NIP与鼻腔和鼻窦关系;MRI扫描可观察鼻腔鼻窦内黏膜及潴留分泌物,可清晰显示肿瘤及周边软组织关系。97例（95.1%）患者的CT检查分期符合病理检查结果,100例（98%）患者的MRI检查分期结果符合的病理检查结果,CT和MRI扫描分期符合率差异无统计学意义（P＞0.05）。结论：CT和MRI诊断NIP的价值较高,联合CT和MRI检查可提高疾病诊断率。     

ALT AST PT T—BIL联合测定对慢性重症肝炎治疗动态监测

目的：探讨慢性重症肝病患者治疗过程中，谷丙转酶，谷草转酶，总胆红素，凝血酶原时间等指标检测的临床探讨。方法：应用日本东亚仪器公司CA一1500型自动血凝分析仪和日本奥林匹斯AU一2700对102例慢性重症肝病患者凝血酶原时间（PT），谷丙转酶（ALT），谷草转转酶（AST），总胆红素（T—BIL）进行了检测，对照组选自我院体检中心健康体检人员（无心、肝、肾功能异常）42例。结果：在慢性重肝炎患者中这4项测定指标与对照组相比有非常显著差异（P〈0．05）。结论：ALT，AST，PT，T—BIL等4项指标的检测可直接反映肝病轻重、肝功能损害状况、可以从多个角度更客观、准确地反映肝病患者在治疗过程中病程进展及预后评估。     

我国医疗机构评审工作的发展设想

借鉴国外的成功经验，结合我国第一轮医疗机构评审工作存在的问题，对我国第二轮医疗机构评审工作提出三个方面的发展设想：在总体思路上，保持医疗机构三级评审体系的连贯性，逐步引入委托第三方评审的模式，提高评审结果的激励效用；在评审标准上，明确评审标准的定位，强化医疗质量和病人安全等内涵指标；在评审方式上，要求评审机构与医疗机构良性互动，加大日常监督检查的力度。     

新生儿游泳与抚触的临床观察及护理

目的:探讨新生儿游泳与抚触对婴儿体格发育及胎便初排、转黄时间的影响。方法:选择368例足月分娩的正常新生儿,将其分为观察组179例,住院期间每日给予新生儿游泳及抚触;对照组189例,每日给予新生儿沐浴,分别记录,比较两组新生儿体重增长情况及胎便初排至转黄时间。结果:新生儿出院时体重与出生体重的平均差值,两组比较有显著性差异(P<0.01)。胎便初排至转黄时间<24h者,两组比较有显著性差异(P<0.01)。结论:新生儿游泳与抚触可促进婴儿体重增长,缩短胎便初排至转黄时间。     

Frequency Map for the Human Cochlear Spiral Ganglion: Implications for Cochlear Implants

The goals of this study were to derive a frequency–position function for the human cochlear spiral ganglion (SG) to correlate represented frequency along the organ of Corti (OC) to location along the SG, to determine the range of individual variability, and to calculate an “average” frequency map (based on the trajectories of the dendrites of the SG cells). For both OC and SG frequency maps, a potentially important limitation is that accurate estimates of cochlear place frequency based upon the Greenwood function require knowledge of the total OC or SG length, which cannot be determined in most temporal bone and imaging studies. Therefore, an additional goal of this study was to evaluate a simple metric, basal coil diameter that might be utilized to estimate OC and SG length. Cadaver cochleae (n = 9) were fixed <24 h postmortem, stained with osmium tetroxide, microdissected, decalcified briefly, embedded in epoxy resin, and examined in surface preparations. In digital images, the OC and SG were measured, and the radial nerve fiber trajectories were traced to define a series of frequency-matched coordinates along the two structures. Images of the cochlear turns were reconstructed and measurements of basal turn diameter were made and correlated with OC and SG measurements. The data obtained provide a mathematical function for relating represented frequency along the OC to that of the SG. Results showed that whereas the distance along the OC that corresponds to a critical bandwidth is assumed to be constant throughout the cochlea, estimated critical band distance in the SG varies significantly along the spiral. Additional findings suggest that measurements of basal coil diameter in preoperative images may allow prediction of OC/SG length and estimation of the insertion depth required to reach specific angles of rotation and frequencies. Results also indicate that OC and SG percentage length expressed as a function of rotation angle from the round window is fairly constant across subjects. The implications of these findings for the design and surgical insertion of cochlear implants are discussed.