A lateral flow test detecting SARS-CoV-2 neutralizing antibodies

It is of critical importance for COVID-19 survivors, vaccine recipients, and public to know whether they have developed neutralizing antibodies or immunity. Here, we describe a 15 minutes lateral flow test for rapid detection of neutralizing antibodies against SARS-CoV-2. All other currently available neutralization tests require hours or days to complete and have to be performed in a well-equipped laboratory. This lateral flow test is the first of its kind and will serve as a convenient diagnostic tool in management of COVID-19 disease.

Quantification and pharmacokinetic study of tumor-targeting agent MHI148-clorgyline amide in mouse plasma using liquid chromatography-electrospray ionization tandem mass spectrometry / 药物分析学报

A high-performance liquid chromatography-electrospray ionization tandem mass spectrometric (HPLC-ESI-MS/MS) method was developed for the quantification of MHI148-clorgyline amide (NMI-amide), a novel tumor-targeting monoamine oxidase A inhibitor, in mouse plasma. The method was validated in terms of sensitivity, precision, accuracy, recovery and stability and then applied to a pharmacokinetic study of NMI-amide in mice following intravenous administration. NMI-amide together with the internal standard (IS), MHI-148, was extracted by protein precipitation using acetonitrile. Multiple reaction monitoring was used for quantification of NMI-amide by detecting m/z transition of 491.2–361.9, and 685.3–258.2 for NMI-amide and the IS, respectively. The lower limit of quantification (LLOQ) of the HPLC–MS/MS method for NMI-amide was 0.005 μg/mL and the linear calibration curve was acquired with R2> 0.99 in the concentration range of 0.005–2 μg/mL. The intra- and inter-day precisions of the assay were assessed by percentage of the coefficient of variations, which was within 9.8% at LLOQ and 14.0% for other quality control samples, whereas the mean accuracy ranged from 86.8% to 113.2%. The samples were stable under storage and experimental conditions. This method was successfully applied to a pharmacokinetic study in mice following intravenous administration of 5 mg/kg NMI-amide.

Differentiation of human bone marrow precursor cells into neuronal-like cells after transplantation into canine spinal cord organotypic slice cultures.

BACKGROUND: Treatments to regenerate different tissue involving the transplantation of bone marrow derived mesenchymal precursor cells are anticipated. Using an alternative methods, in vitro organotypic slice culture method, would be useful to transplant cells and assessing the effects. This study was to determine the possibility of differentiating human bone marrow precursor cells into cells of the neuronal lineage by transplanting into canine spinal cord organotypic slice cultures. METHODS: Bone marrow aspirates were obtained from posterior superior iliac spine (PSIS) of patients that had undergone spinal fusion due to a degenerative spinal disorder. For cell imaging, mesenchymal precursor cells (MPCs) were pre-stained with PKH-26 just before transplantation to canine spinal cord slices. Canine spinal cord tissues were obtained from three adult beagle dogs. Spinal cords were cut into transverse slices of 1 mm using tissue chopper. Two slices were transferred into 6-well plate containing 3 ml DMEM with antibiotics. Prepared MPCs (1×10(4)) were transplanted into spinal cord slices. On days 0, 3, 7, 14, MPCs were observed for morphological changes and expression of neuronal markers through immunofluorescence and reverse transcription-polymerase chain reaction (RT-PCR). RESULTS: The morphological study showed: spherical cells in the control and experiment groups on day 0; and on day 3, cells in the control group had one or two thick, short processes and ones in the experiment group had three or four thin, long processes. On day 7, these variously-sized processes contacted each other in the experiment group, but showed typical spindle-shaped cells in the control group. Immunofluorescence showed that PKH-26(+) MPCs stained positive for NeuN(+) and GFAP(+) in experimental group only. Also RT-PCR showed weak expression of ß-tubulin III and GFAP. CONCLUSIONS: Human bone marrow mesenchymal precursor cells (hMPCs) have the potential to differentiate into the neuronal like cells in this canine spinal cord organotypic slice culture model. Furthermore, these findings suggested the possibility that these cells can be utilized to treat patients with spinal cord injuries.

Phytochemical analysis of medicinal plants with kidney protective activities / 中国结合医学杂志

In view of the increasing number of patients undergoing kidney dialysis or transplant every year, a survey of the literature on renal protective medicinal plants was undertaken. Most of them are from traditional Chinese medicine (TCM). Although many of the medicinal herbs reported have not been investigated in terms of active chemical ingredients, some do have compounds well characterized. They fall into a wide range of structures. Several groups of compounds with well established activities are discussed. These include: antioxidant phenolic compounds like tannins, flavonoids, isoflavonoids, unsaturated organic acids and lignans; circulation enhancing compounds like saponins, and basic alkaloids with multiple targets (G-protein coupled receptors). Also presented are proinflammatory and antiinflammatory fatty acids like linoleic (n-6) and α-linolenic (n-3) acids, respectively. Attention is also drawn to the plants containing nephrotoxic aristolochic acid. Different directions of future research are also presented. We hope that this review may provide some leads for new drug discovery and development, and more rational application of TCM.

Effect of lumbar angular motion on central canal diameter: positional MRI study in 491 cases / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Lumbar spinal stenosis is a common problem that is receiving attention with the advent of novel treatment procedures. Prior positional MRI studies demonstrated lumbar canal diameter changes with flexion and extension. There have not been any studies to examine the amount of spinal canal diameter change relative to the amount of angular motion. The purpose of this study was to evaluate the correlation between the lumbar canal diameter change and the angular motion quantitatively.</p><p><b>METHODS</b>Positional MRI (pMRI) images for 491 patients, including 310 males and 181 females (16 years-85 years of age), were obtained with the subjects in sitting flexion 40 degree, upright, and with extension of 10 degrees within a 0.6 T Positional MRI scanner. Quantitative measurements of the canal diameter and segmental angle of each level in the sagittal midline plane were obtained for each position. Then the diameter change and angular motion were examined for correlation during flexion and extension with linear regression analysis.</p><p><b>RESULTS</b>The lumbar segmental angles were lordotic in all positions except L1-2 in flexion. The changes of canal diameters were statistically correlated with the segmental angular motions during flexion and extension (P < 0.001). The amount of canal diameter change correlated with the amount of angular change and was expressed as a ratio.</p><p><b>CONCLUSIONS</b>Positional MRI demonstrated the amount of spinal canal diameter change that was statistically correlated with the segmental angular motion of the spine during flexion and extension. These results may be used to predict the extent of canal diameter change when interspinous devices or positional changes are used to treat spinal stenosis and the amount of increased canal space may be predicted with the amount of angular or positional change of the spine. This may correlate with symptomatic relief and allow for improved success in the treatment of spinal stenosis.</p>