薄层色谱法在当前中药质量标准中的应用探讨

薄层色谱鉴别在历版《中国药典》中的应用经历了从无到有、从少到多的过程；而薄层扫描含量测定在最近几版《中国药典》中的应用比例逐渐降低。随着对中药质量标准体系要求的进一步提高，薄层色谱法的不足之处陆续显现，如仪器普及率低、设备并不简单、结果重复性和稳定性较差、鉴别速度及准确性不及高效液相色谱法、展开剂毒性大等，逐渐不合时宜。在制定中药质量标准时，研究者不应该墨守成规，薄层色谱鉴别也不应该是雷打不动的定性鉴别必备选项。高效液相色谱法具备完全取代薄层色谱法的可行性，薄层色谱法可作为高效液相色谱法的补充。为充分降低检测成本、缩短检测周期、提高鉴别效率，笔者建议中药质量标准体系应该大幅减少薄层色谱鉴别方法的应用，增加高效液相特征图谱鉴定，尽量做到“一个条件，一张图谱”；除非确有必要，《中国药典》等国家质量标准体系应将薄层色谱鉴别作为推荐方法，而非强制标准。     

地黄不同炮制品薄层色谱鉴别方法的建立

目的:建立地黄不同炮制品的薄层色谱鉴别方法。方法:以D-果糖、梓醇、蔗糖、棉子糖、水苏糖、蜜二糖及甘露三糖为对照品,考察提取溶剂(水,20%甲醇,50%甲醇,80%甲醇),展开剂(正丁醇-甲醇-三氯甲烷-冰乙酸-水,乙酸乙酯-吡啶-冰乙酸-水,正丁醇-冰乙酸-水),显色剂(苯胺-二苯胺-磷酸溶液,茚三酮溶液),点样量(2,4,6μL),检视条件(日光,日光底部灯,365 nm和254 nm)对薄层色谱分析的影响,确定生地黄及熟地黄饮片的供试品溶液制备方法和最佳薄层色谱条件。结果:采用薄层色谱高效硅胶G板,以正丁醇-甲醇-三氯甲烷-冰乙酸-水(13∶5∶5∶1∶2)为展开剂展开,喷以苯胺-二苯胺-磷酸溶液,110℃下加热显色,于日光底部灯下进行检视,所得地黄不同炮制品薄层色谱分离效果和显色效果较佳,斑点清晰且特征性好。结论:该薄层色谱鉴别方法操作简便易行,定性特征明显、结果直观,可有效鉴别地黄不同炮制品,并可为熟地黄的炮制终点确定提供实验依据。     

载As2O3 pH敏感钙砷复合物脂质体的制备及体外评价

目的 制备pH敏感释药的As₂O₃脂质体，并进行体外评价。方法 采用薄膜分散法制备含钙离子脂质体，然后用离子沉淀法孵育制备钙砷复合物脂质体（CaAs-LP）。测定CaAs-LP的粒径、Zeta电位及多分散系数（PDI）；透射电子显微镜观察脂质体的形态；电感耦合等离子体发射光谱仪测定纳米药物的载药量与包封率；透析袋法考察其体外释药特性。噻唑蓝（MTT）法考察未载药脂质体及CaAs-LP对人源性乳腺癌MCF-7细胞、人源性脑胶质瘤U87细胞和人源性肝癌HepG2细胞的毒性；共聚焦显微镜考察U87细胞对CaAs-LP的摄取效率。结果 制备的CaAs-LP呈规整类球型，粒径约为（117.16±1.94）nm，包封率和载药量分别为（74.31±2.11）%、（8.31±0.13）%。体外释放研究表明，CaAs-LP具有明显的缓释以及pH响应释药特征。未载药的脂质体在MCF-7、U87、HepG2和L02细胞中的生物相容性良好；CaAs-LP抑制肿瘤细胞生长的作用较原药有所上升，半数抑制浓度（IC₅₀）值分别为11.91、4.90、19.41、27.59 μmol/L。细胞摄取研究表明肝癌细胞对脂质体具有良好的摄取。结论 CaAs-LP具备显著的缓释以及pH响应释药的特性，在肿瘤治疗方面具有较好的应用前景。     

Correlation of ischemic ophthalmopathy with lacunar infarction

AIM: To investigate the effects of nintedanib thermo-sensitive hydrogel (NTH) on neovascularization and related markers in corneal alkali burns of Wistar rats. METHODS: NTH was prepared by grinding, and its phase-transition temperature was determined. Thirty specific-pathogen-free Wistar rats served as a model of corneal alkali burn in the right eye were randomly divided into 3 groups (n=10, each): model group treated with 0.9% saline once a day, NTH group with 0.2% nintedanib b.i.d, and dexamethasone (DEX) group with DEX ointment once a day. The left eye of rats served as the controls. The corneal transparency was observed under a slit-lamp microscope, and the area of neovascularization was calculated. On day 7, the rats were sacrificed, and the cornea was removed and embedded with paraffin, then stained with hematoxylin-eosin, and the expression of VEGFR-2 and CD31 in the corneal tissues of each group was detected by immunofluorescence. RESULTS: The phase-transition temperature of nintedanib obtained by grinding was 37°C after adding artificial tears. The results of the alkali burn model indicated that the growth rate of neovascularization in the NTH group was slower than that in the model group, and the neovascularization area was significantly smaller than that in the model group (P<0.05). Moreover. CD31 and VEGFR-2 expression levels in the NTH group were significantly lower than those in the model group. CONCLUSION: NTH becomes colloidal at body temperature, which is beneficial for releasing the drug slowly and can significantly inhibit the neovascularization of corneal induced by alkali burn in rats.     

Amniotic Membrane Transplant for Bullous Keratopathy: Confocal Microscopy & Anterior Segment Optical Coherence Tomography

Purpose: To assess amniotic membrane retention after amniotic membrane transplant in bullous keratopathy patients and whether there were any corneal structural changes that may hinder further penetrating keratoplasty

Methods: A retrospective study including 22 patients who have undergone amniotic membrane transplant from 1 Jan 1998 till 30 Jun 2016. Confocal microscopy and anterior segment optical coherence tomography (ASOCT) were performed to assess the retention of amniotic membrane and to detect any corneal structural changes. The comparison was made with 5 controls who had bullous keratopathy awaiting endothelial keratoplasty.

Results: Patients had a mean follow-up of 61 ± 33.7 months. Pain reduction was significant (p < .001) although it did not significantly correlate with the regularity of the superficial, intermediate or basal epithelial layers, nor with the retention of the amniotic membrane. No long-term structural changes that may hinder future penetrating keratoplasty were detected.

Conclusion: This procedure is a safe and effective long-term treatment for symptomatic bullous keratopathy patients.     

Hippo/YAP信号通路在眼部作用的研究进展

Hippo-YAP通路在机体发育和疾病发生中均具有重要作用。Hippo-YAP通路的调节紊乱可能导致病理组织过度生长和肿瘤的进展；近年来研究发现，Hippo-YAP信号通路的异常调节可能与眼部疾病相关，如圆锥角膜、Sveinsson 脉络膜视网膜萎缩和视网膜变性等，本文就Hippo/YAP 在眼部作用的研究进展进行系统综述，为眼部疾病的治疗提供理论基础。     

A simplified and inexpensive method for the preparation of fresh or fixed bone samples for forensic histological examination

ABSTRACT

The histological analysis of bone for forensic application requires thin sections to be prepared from extracted bone of suitable quality for visualization through conventional light microscopy and (if required) the measurement of microstructural features, such as osteons. While a number of protocols for the preparation of thin sections exist, they are often time consuming and complex, or require expensive and non-portable equipment. A revised protocol is presented for obtaining high quality thin sections for light microscopy and histological analyses, tested in fresh, fixed, and dry archaeological cortical bone. It does not require extensive experience, or expensive materials or equipment, and can be further adapted for use with manual tools if necessary.