蒙药绿松石的质量标准研究＊

目的 建立蒙药绿松石的质量标准。方法 收集不同产地绿松石，共10批。观察绿松石样品和粉末的性状并进行理化鉴别；按2020年版《中国药典》（四部）通则方法测定绿松石样品中水分、浸出物含量；采用原子吸收光谱法测定绿松石样品铜元素含量。结果 绿松石为不规则、周围带有黑石的块状物，表面蓝绿色，体重，质硬脆，难砸碎，断面呈贝壳状，蜡样光泽，粉末呈灰绿色，无臭，味淡；理化鉴别结果显示，呈铜盐反应；10批次样品中水分含量为0.41%-3.94%（SD=1.37%），浸出物含量为0.21%-0.81%（SD=0.21%），铜元素含量为3.03%-4.63%（SD=0.63%）。结论 初步拟定绿松石中水分含量不得超多5.0%、浸出物含量不得低于0.10%，铜元素含量应为2.60%-4.84%，制定的标准可用于蒙药材绿松石的质量控制。     

Adverse events due to unnecessary radiation exposure in medical imaging reported in Finland

IntroductionAdverse events in radiology are quite rare, but they do occur. Radiation safety regulations and the law obligate organizations to report certain adverse events, harm and near misses, especially events related to patients' health and safety. The aim of this study was to describe and analyse incidents related to radiation safety issues reported in Finland.MethodsThe data were collected from incident reports documented by radiology personnel concerning notifications of abnormal events in medical imaging made to the Radiation and Nuclear Safety Authority between 2010 and 2017. During these eight years, 312 reports were submitted. Only events reported from radiology departments were included; nuclear medicine, radiotherapy and animal radiology cases were excluded. The final number of reports was 293 (94%).ResultsThe majority of the 293 approved reports were related to computed tomography (CT, 68.3%) and to X-ray examinations (27.6%). Altogether 82.9% of those irradiated were adults, most of whom were exposed to unnecessary radiation through CT (86.5%), 5.5% were children, and 4.4% pregnant women. The most common effective dose of unnecessary radiation was 1 mSv or less (89.7% of all examinations). The highest effective doses were reported in CT (from under 1 mSv–20 mSv and above). The reasons for the adverse events were incorrect identification (32%), incorrect procedure, site or side (30%); and human errors or errors of knowledge (20%).ConclusionAdverse events occurred especially in CT examinations. It is important to collect and analyse incident data, assess the harmful events, learn from them and aim to reduce adverse events.Implications for practiceThis study emphasizes the need for radiological personnel to obtain evidence-based information on adverse events and focus on training to improve patient safety.     

家兔骨延长后血清微量元素的变化

目的 :观察骨延长术对血清微量元素的影响。方法 :采用实验家兔 6只 ,造成左胫骨中段骨延长模型 ,定期耳缘静脉采血。原子吸收分光光度仪测定血清中锌、铜、铁的含量。结果 :骨延长术后血清铜元素含量呈上升趋势 ,血清铁、锌元素含量明显下降。在延长结束后 5d时与术前比较有明显差别 (P <0 .0 5 )。结论 :骨延长术后 ,血清铁、锌元素含量呈阶段性下降 ,适时予以补充 ,有利于骨组织的修复。     

The distribution of lead in human hemopoietic tissue and spongy bone after lead poisoning and Ca-EDTA chelation therapy

Two iliac crest needle biopsies were taken from a 43-year-old lead-poisoned woman during and after completion of a Ca-EDTA treatment. By atomic absorption spectroscopy the first and second biopsy were found to contain 56, respectively 41.6 g lead/g wet tissue. In both biopsies 36% of the lead was extractable in 0.1 N HCl. Electron microbeam X-ray analysis proved to have too low sensitivity for quantitation of the lead in these biopsies. Laser microbeam mass analysis (LAMMA), performed only on the second biopsy, revealed a high and fairly constant residual lead concentration in all bone marrow cell nuclei (approximately 55 g/g) and a low lead concentration in the cytoplasm of the same cells (4–12 (g/g). The extracellular bone matrix lead was greatly concentrated in the superficial 3–6 m osteoid zone of the bony trabeculae and totally absent from deeper parts of the mineralized matrix. The LAMMA results are in good agreement with those of subcellular fractionation experiments and atomic absorption spectroscopy, provided that the relative volume fraction of nucleus and cytoplasm is accounted for. The high residual osteoid lead after completed chelation therapy indicates that lead has a stronger affinity for the organic than the mineral components of bone matrix.     

Immunolocalization of lamins and nuclear pore complex proteins by atomic force microscopy

The nuclear envelope functions as a selective barrier separating the nuclear from the cytosolic compartment. Nuclear pore complexes (NPCs) mediate nuclear import and export of macromolecules and, therefore, are potential regulators of gene expression. In this study we applied atomic force microscopy (AFM) to visualize the three dimensional (3D) structure of individual NPCs in the absence and presence of two different antibodies, one directed against a pore protein (gp62) and another directed against Xenopus lamin LIII, a component of the nuclear lamina, a filament meshwork localized on the nucleoplasmic side of the nuclear envelope (NE) adjacent to and interacting with NPCs. Using 12-nm gold-labelled secondary antibodies and transmission electron microscopy we could clearly localize the primary single anti-gp62 antibody on NPCs and the primary single anti-LIII antibody between NPCs. Using AFM, the secondary antibodies against anti-gp62 could be detected as particles 7 nm in height on the nucleoplasmic face of NPCs. The secondary antibodies against anti-LIII could be clearly identified between NPCs. The secondary antibodies, attached to a 12-nm colloidal gold particle and visualized on glass, revealed similar shapes and heights as found on NEs. According to the 3D images, the volume of a single gold particle conjugated with secondary antibodies was 10 203 nm³. This volume is equivalent to the volume of 38 IgG molecules associated with one individual gold particle. A similar volume of 11 987 nm³ was calculated from a model assuming that the 150-kDa IgG molecules perfectly cover the spherical gold particle. We conclude that AFM can be used for identifying antibodies or other macromolecules associated with biomembranes.     

Polarized ion transport during migration of transformed Madin-Darby canine kidney cells

Epithelial cells lose their usual polarization during carcinogenesis. Although most malignant tumours are of epithelial origin little is known about ion channels in carcinoma cells. Previously, we observed that migration of transformed Madin-Darby canine kidney (MDCK-F) cells depended on oscillating K⁺ channel activity. In the present study we examined whether periodic K⁺ channel activity may cause changes of cell volume, and whether K⁺ channel activity is distributed in a uniform way in MDCK-F cells. After determining the average volume of MDCK-F cells (2013±270 m³; n=8) by means of atomic force microscopy we deduced volume changes by calculating the K⁺ efflux during bursts of K⁺ channel activity. Therefore, we measured the membrane conductance of MDCK-F cells which periodically rose by 22.3±2.5 nS from a resting level of 6.5±1.4 nS (n=12), and we measured the membrane potential which hyperpolarized in parallel from –35.4±1.2 mV to –71.6±1.8 mV (n=11). The distribution of K⁺ channel activity was assessed by locally superfusing the front or rear end of migrating MDCK-F cells with the K⁺ channel blocker charybdotoxin (CTX). Only exposure of the rear end to CTX inhibited migration providing evidence for horizontal polarization of K⁺ channel activity in transformed MDCK-F cells. This is in contrast to the vertical polarization in parent MDCK cells. We propose that the asymmetrical distribution of K⁺ channel activity is a prerequisite for migration of MDCK-F cells.     

Molecular weights of individual proteins correlate with molecular volumes measured by atomic force microscopy

 Proteins are usually identified by their molecular weights, and atomic force microscopy (AFM) produces images of single molecules in three dimensions. We have used AFM to measure the molecular volumes of a number of proteins and to determine any correlation with their known molecular weights. We used native proteins (the TATA-binding protein Tbp, a fusion protein of glutathione-S-transferase and the renal potassium channel protein ROMK1, the immunoglobulins IgG and IgM, and the vasodilator-stimulated phosphoprotein VASP) and also denatured proteins (the red blood cell proteins actin, Band 3 and spectrin separated by SDS-gel electrophoresis and isolated from nitrocellulose). Proteins studied had molecular weights between 38 and 900 kDa and were imaged attached to a mica substrate. We found that molecular weight increased with an increasing molecular volume (correlation coefficient = 0.994). Thus, the molecular volumes measured with AFM compare well with the calculated volumes of the individual proteins. The degree of resolution achieved (lateral 5 nm, vertical 0.2 nm) depended upon the firm attachment of the proteins to the mica. This was aided by coating the mica with suitable detergent and by imaging using the AFM tapping mode which minimizes any lateral force applied to the protein. We conclude that single (native and denatured) proteins can be imaged by AFM in three dimensions and identified by their specific molecular volumes. This new approach permits detection of the number of monomers of a homomultimeric protein and study of single proteins under physiological conditions at the molecular level. Received: 14 February 1997 / Received after revision: 8 September 1997 / Accepted: 8 September 1997     

Atomic absorption spectrometry in pharmaceutical analysis

A short review of the principles of atomic absorption spectrometry (AAS) — sources, atomizers, background correction, instrumentation, sample preparation, sensitivity, limit of detection, etc. — is given. The technique can be applied for impurity tests for trace metals as well as for assay of various commonly occurring elements in pharmaceuticals. The application of AAS in pharmaceutical analysis is illustrated with 17 examples.     

常见动物胆汁宏量和微量元素的原子吸收分析及研究

目的　通过原子吸收对胆汁中的宏量元素与微量元素进行测定并进行分析研究。方法　利用原子吸收对 8种动物胆汁中金属元素进行测定。结果　各种属动物胆汁中含有的金属元素差异很大 ,兔胆汁含铜、钙、镁最多 ;牛胆汁含锌、铁、钾最多 ;猪胆汁含锰最多 ,而羊胆汁含金属离子的总量最少。结论　提示各种动物胆汁微量元素的含量各不相同 ,其药效有别 ,不能随意代替     

抗流感滴鼻剂不同除杂工艺微量元素的含量分析

目的：探讨不同除杂方法对微量元素含量的影响。方法：采用原子荧光法和电感耦合等离子体发射光谱法测定不同除杂方法所得澄清液中As，Hg，Pb，Fe，Mn，Zn，Cu的含量。结果：与原液比较，絮凝澄清液中As，Hg，Pb的去除率分别为57．1％，50．0％，39．6％，并分别为醇沉澄清液去除率的2．00，1．50，1．12倍；絮凝澄清液中的Fe，Mn，Zn，Cu保留率分别为90．6％，95．6％，91．7％，93．9％，并分别为醇沉澄清液保留率的1．09，1．29，1．15，1．28倍。结论：从有害元素的去除率及有益元素的保留率来看，絮沉工艺优于醇沉工艺。