Gold nanostructure-integrated conductive microwell arrays for uniform cancer spheroid formation and electrochemical drug screening.

Cancer spheroids, which mimic distinct cell-to-cell and cell-extracellular matrix interactions of solid tumors in vitro, have emerged as a promising tumor model for drug screening. However, owing to the unique characteristics of spheroids composed of three-dimensionally densely-packed cells, the precise characterizations of cell viability and function with conventional colorimetric assays are challenging. Herein, we report gold nanostructure-integrated conductive microwell arrays (GONIMA) that enable both highly efficient uniform cancer spheroid formation and precise electrochemical detection of cell viability. A nanostructured gold on indium tin oxide (ITO) substrate facilitated the initial cell aggregation and further 3D cell growth, while the non-cytophilic polymer microwell arrays restricted the size and shape of the spheroids. As a result, approximately 150 human glioblastoma spheroids were formed on a chip area of 1.13 cm2 with an average diameter of 224 µm and a size variation of only 5% (±11.36 µm). The high uniformity of cancer spheroids contributed to the stability of electrical signals measuring cell viability. Using the fabricated GONIMA, the effects of a representative chemotherapeutic agent, hydroxyurea, on the glioblastoma spheroids were precisely monitored under conditions of varying drug concentrations (0-0.3 mg/mL) and incubation times (24-48 h). Therefore, we conclude that the newly developed platform is highly useful for rapid and precise in vitro drug screening, as well as for the pharmacokinetic analyses of specific drugs using 3D cellular cancer models.

Recent Advances in Electrochemical Biosensors for Monitoring Animal Cell Function and Viability.

Redox reactions in live cells are generated by involving various redox biomolecules for maintaining cell viability and functions. These qualities have been exploited in the development of clinical monitoring, diagnostic approaches, and numerous types of biosensors. Particularly, electrochemical biosensor-based live-cell detection technologies, such as electric cell-substrate impedance (ECIS), field-effect transistors (FETs), and potentiometric-based biosensors, are used for the electrochemical-based sensing of extracellular changes, genetic alterations, and redox reactions. In addition to the electrochemical biosensors for live-cell detection, cancer and stem cells may be immobilized on an electrode surface and evaluated electrochemically. Various nanomaterials and cell-friendly ligands are used to enhance the sensitivity of electrochemical biosensors. Here, we discuss recent advances in the use of electrochemical sensors for determining cell viability and function, which are essential for the practical application of these sensors as tools for pharmaceutical analysis and toxicity testing. We believe that this review will motivate researchers to enhance their efforts devoted to accelerating the development of electrochemical biosensors for future applications in the pharmaceutical industry and stem cell therapeutics.

The clinical features of 17 patients with the myelin oligodendrocyte glycoprotien antibody-associated disease / 中风与神经疾病杂志

@#Objective To investigate the clinical features of the myelin oligodendrocyte glycoprotien antibody-associated disease(MOGAD).Methods The clinical data of 17 MOGAD patients who were hospitalized in The First Affiliated Hospital of Sun Yat-sen University from January 2017 to June 2019 were retrospectively analyzed.Then we summarized the clinical and imagine features of the MOGAD.Results Seventeen patients,including 11 males and 6 females,were recruited in this study,and the average age of onset was (27.76±12.22)years old.Ten patients presented as ON,9 cases manifested as myelitis,10 cases presented as the symptoms of brain damage,and 1 case as the ADEM.The MOG antibody in serum of 17 patients were positive,and the MOG antibody titers were from 1:10 to 1:320.Among them,the MOG antibody in cerebrospinal fluid of 7 patients were positive,and the antibody titers were from 1:1 to 1:32.Other autoimmune antibodies were positive in a small group of these patients.Magnetic resonance imaging(MRI) scan are abnormal in all the patients at onset.The majority lesions appear as poorly demarcated hyperintensities on T2-weighted and T2FLAIR images,some of them showed edge enhancement.All patients were treated with intravenous methylprednisolone,and 13 patients were treated with IVIG.The symptoms of 16 cases were improved within a month,and another case improved after the plasma exchange.And 6 cases recurred within a year.Conclusion The clinical features of the MOGAD were various,mainly including ON,myelitis,encephalitis,meningoencephalitis i.e.Early immunotherapy can result in having a complete or almost complete recovery.However,some patients had the risk of relapse.

Definition of dengue risk thresholds of route index and mosq-ovitrap index / 预防医学

Objective @#To estimate the risk threshold of route index（RI）and mosq-ovitrap index（MOI）based on Breteau index（BI）,as supplements for dengue fever risk monitoring in specific habitats. @*Methods @#Two towns and two streets were selected from nine towns（streets）in Jiashan County,and then one village（community）was selected from each of them as a Aedes albopictus monitoring site. The BI,RI and MOI were employed at the same time and area from April to October in the year 2018. Linear regression models were built with RI,MOI and BI to calculate the dengue risk threshold of RI and MOI according to BI. @*Results @#The linear regression model of BI（X）and RI（Y）was Y=0.145+0.662X（P<0.05）,of BI（X）and MOI（Y）was Y=3.423+0.524X（P<0.05）. If BI=5（having risk of transmission of dengue fever）,then RI=3.455（95%CI：1.717-5.198）,MOI=6.043（95%CI：-0.327-12.417）. If BI=10（having risk of outbreak）,then RI=6.765（95%CI：5.018-8.518）,MOI=8.663（95%CI：2.260-15.071）. If BI=20（having risk of epidemic）,then RI=13.385（95%CI：11.326-15.453）,MOI=13.903（95%CI：6.352-21.461）.@*Conclusion @#The dengue fever risk threshold of RI estimated by BI had a narrow 95%CI and could be applied for dengue fever risk assessment,while the risk threshold of MOI had a wide 95%CI and the application value needed further study.

Detection of biogenic amines in C57BL/6 mice brain by capillary electrophoresis electrokinetic supercharging.

Ischemic stroke is caused when blood flow to the brain is stopped and is a major cause of death and long term disability across the globe. Excessive release of neurotransmitters is triggered in the brain by ischemia that mediates neuronal damage and causes ischemic injury. In this study, a simple, sensitive, and on-line preconcentration capillary electrophoresis method based on electrokinetic supercharging (EKS) was developed for the determination of the biogenic amines including dopamine (DA), epinephrine (E), and norepinephrine (NE) in C57BL/6 mice brain. Under the optimized conditions, the analytes were concentrated and detected within 10 min. The detection limits for the analytes ranged from 0.42 to 0.57 ng mL(-1) for a mice brain matrix. With the proposed method, the analyses of three neurochemical amines in C57BL/6 mice brain tissue during cerebral ischemic/reperfusion had been performed successfully.

Multivariate analysis of relationships between material properties and hygroscopicity of Chinese medicine raw materials / 药学学报

Material properties and hygroscopicity were determined. Principal component analysis and partial least squares regression were applied to evaluate relationships between material properties and hygroscopicity of Chinese medicine raw materials. The results showed that hygroscopicity was correlated with water content, particle size distribution, water soluble characteristic and cohesion. Balanced moisture content was positively correlated with water content, particle size distribution, water soluble characteristic and cohesion. Moisture absorption velocity was negatively correlated with particle size distribution, protruding degree and positively correlated with water soluble characteristic and cohesion. Moisture absorption acceleration was positively correlated with water content, particle size distribution and negatively correlated with water soluble characteristic and cohesion. Hygroscopicity of Chinese medicine raw materials is interpreted in terms of physics.

2.6 A resolution crystal structure of the bacterioferritin from Azotobacter vinelandii.

The crystal structure of the bacterioferritin from Azotobacter vinelandii has been determined at 2.6 A resolution. Both the low occupancy of one iron ion in the dinuclear iron center and the deviation of its adjacent residue His130 from the center suggest migration of the iron ion from the dinuclear iron site to the inner nucleation site. The concerted movement of His130 and Glu47 may admit a dynamic gating mechanism for shift of the oxidized iron ion. Ba2+ binding to the fourfold channel implicates that the channel bears Fe2+ conductivity and selectivity to provide a route for iron access to the inner cavity during core formation.

[Determination of flavone for Scutellaria baicalensis from different areas by HPLC].

OBJECTIVE: To describe the difference between native and nonative herbs by determining contents of seven kinds of flavone for twenty-five samples from seventeen areas. METHODS: HPLC. Fluid phase: MEOH-H2O-CH3COOH(ICE) (41:59:0.2) and (50:50:0.2). Detection wavelength: 275. RESULTS: The contents of baicalin are 6%-9%, wogenin are 2%-8%, baicalein are 0.1%-1.6%, neobaicalein are 0.01%-0.2%, wogonin are 0.01%-0.3%, visidulin and oroxylin are trace amounts or undetected. CONCLUSION: The native and nonative herbs have no distinct differce in absolute component ratio. The ratio of baicalin and wogenin is under three. The ratio of baicalin and baicalein, baicalin and wogonin is between twenty and fifty.

Determination of flavone for Scutellaria baicalensis from different areas by HPLC / 中国中药杂志

<p><b>OBJECTIVE</b>To describe the difference between native and nonative herbs by determining contents of seven kinds of flavone for twenty-five samples from seventeen areas.</p><p><b>METHODS</b>HPLC. Fluid phase: MEOH-H2O-CH3COOH(ICE) (41:59:0.2) and (50:50:0.2). Detection wavelength: 275.</p><p><b>RESULTS</b>The contents of baicalin are 6%-9%, wogenin are 2%-8%, baicalein are 0.1%-1.6%, neobaicalein are 0.01%-0.2%, wogonin are 0.01%-0.3%, visidulin and oroxylin are trace amounts or undetected.</p><p><b>CONCLUSION</b>The native and nonative herbs have no distinct differce in absolute component ratio. The ratio of baicalin and wogenin is under three. The ratio of baicalin and baicalein, baicalin and wogonin is between twenty and fifty.</p>

Role of various concentrations of glucose and insulin on expression of transforming growth factor-?_1 in HK2 cells / 中华内分泌代谢杂志

HK-2 cells were cultured with various concentrations of glucose and insulin for 12,24,48,72 h.Transforming growth factor-?_1(TGF-?_1) protein in supematant was measured by ELISA,while TGF-?_1 mRNA expression was assessed by RT-PCR.Data showed that high concentration of glucose and insulin up-regulated the expression of TGF-?_1 in HK-2 cells through different pathways.