ResearchPad - Medical Laboratory Technology Default RSS Feed en-us © 2020 Newgen KnowledgeWorks <![CDATA[A small protein probe for correlated microscopy of endogenous proteins]]>

Probes are essential to visualize proteins in their cellular environment, both using light microscopy as well as electron microscopy (EM). Correlated light microscopy and electron microscopy (CLEM) requires probes that can be imaged simultaneously by both optical and electron-dense signals. Existing combinatorial probes often have impaired efficiency, need ectopic expression as a fusion protein, or do not target endogenous proteins. Here, we present FLIPPER-bodies to label endogenous proteins for CLEM. Fluorescent Indicator and Peroxidase for Precipitation with EM Resolution (FLIPPER), the combination of a fluorescent protein and a peroxidase, is fused to a nanobody against a target of interest. The modular nature of these probes allows an easy exchange of components to change its target or color. A general FLIPPER-body targeting GFP highlights histone2B-GFP both in fluorescence and in EM. Similarly, endogenous EGF receptors and HER2 are visualized at nm-scale resolution in ultrastructural context. The small and flexible FLIPPER-body outperforms IgG-based immuno-labeling, likely by better reaching the epitopes. Given the modular domains and possibilities of nanobody generation for other targets, FLIPPER-bodies have high potential to become a universal tool to identify proteins in immuno-CLEM with increased sensitivity compared to current approaches.

Electronic supplementary material

The online version of this article (10.1007/s00418-018-1632-6) contains supplementary material, which is available to authorized users.

<![CDATA[Anti-Insulin Antibodies and Adverse Events with Biosimilar Insulin Lispro Compared with Humalog Insulin Lispro in People with Diabetes]]>


Background: SAR342434 (SAR-Lis) is a biosimilar (follow-on) of insulin lispro (Humalog®; Ly-Lis). Two randomized, controlled, open-label, parallel-group, phase 3 studies were conducted to compare the efficacy and safety of SAR-Lis and Ly-Lis, both in combination with insulin glargine (Lantus®). SORELLA 1 was a 12-month study in 507 people with type 1 diabetes mellitus (T1DM); SORELLA 2 was a 6-month study in 505 people with type 2 diabetes mellitus (T2DM). In this study, the impact of anti-insulin antibodies (AIA) to SAR-Lis and Ly-Lis on safety and glycemic control is reported.

Methods: AIA were measured regularly throughout both studies at a centralized laboratory blinded to treatment groups using a drug-specific AIA assay. The AIA status (positive or negative), AIA titers, and cross-reactivity to human insulin, insulin glargine, and insulin glargine metabolite M1 were analyzed. The potential effect of AIA on safety, particularly as related to hypersensitivity reactions, hypoglycemia, and treatment-emergent adverse events, as well as on glycemic control (HbA1c, insulin dose), was evaluated.

Results: AIA positive status at baseline was similar for the two insulins, but higher in T1DM than in T2DM. In both studies, the percentage of people newly developing AIA in the two treatment groups, or having a ≥4-fold increase in AIA titers, did not differ. No relationship was observed between maximum individual AIA titers and change in HbA1c or insulin dose, hypoglycemia, or hypersensitivity reactions or between efficacy/safety measures and subgroups by presence or absence of treatment-emergent AIA. Hypersensitivity events and events adjudicated as allergic reactions were few and did not differ between the two groups.

Conclusion: Insulin lispro SAR342434 and the originator insulin lispro had a similar immunogenicity profile in people with T1DM or T2DM.

<![CDATA[Image-guided Coring for Large-scale Studies in Molecular Pathology]]> <![CDATA[Decline in Antigenicity of Tumor Markers by Storage Time Using Pathology Sections Cut From Tissue Microarrays]]>

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<![CDATA[Does Electroencephalography Contribute to Examining Children with Attention Deficit Hyperactivity Disorder?]]> ]]> <![CDATA[New Spectrophotometric Method for Determining Nitrogen Dioxide in Air Using 2,2-azino-bis(3-ethyl benzothiazoline)-6-Sulfonic Acid-Diammonium Salt and Passive Sampling]]>

A new simple and highly sensitive spectrophotometric method for determining nitrogen dioxide in air was developed. The method is based on converting atmospheric nitrogen dioxide to nitrite ions within the IVL passive samplers used for samples collection. Acidifying nitrite ions with concentrated HCl produced the peroxynitrous acid oxidizing agent which was measured using 2, 2-azino-bis(3-ethyl benzothiazoline)-6-sulfonic acid-diammonium salt (ABTS) as reducing coloring agent. A parallel series of collected samples were measured for its nitrite content using a validated ion chromatographic method.

The results obtained using both methods were compared in terms of their sensitivity and accuracy. Developed spectrophotometric method was shown to be one order of magnitude higher in sensitivity compared to the ion chromatographic method. Quantitation limits of 0.05 ppm and 0.55 μg/m3 were obtained for nitrite ion and nitrogen dioxid, respectively. Standard deviations in the ranges of 0.05–0.59 and 0.63–7.92 with averages of 0.27 and 3.11 were obtained for determining nitrite and nitrogen dioxide, respectively.

Student-t test revealed t-values less than 6.93 and 4.40 for nitrite ions and nitrogen dioxide, respectively. These values indicated insignificant difference between the averages of the newly developed method and the values obtained by ion chromatography at 95% confidence level.

Compared to continuous monitoring techniques, the newly developed method has shown simple, accurate, sensitive, inexpensive and reliable for long term monitoring of nitrogen dioxide in ambient air.