7 research outputs found
Development of a Miniature Mass Spectrometry System for Point-of-Care Analysis of Lipid Isomers Based on Ozone-Induced Dissociation
Disorder of lipid homeostasis is closely associated with
a variety
of diseases. Although mass spectrometry (MS) approaches have been
well developed for the characterization of lipids, it still lacks
an integrated and compact MS system that is capable of rapid and detailed
lipid structural characterization and can be conveniently transferred
into different laboratories. In this work, we describe a novel miniature
MS system with the capability of both ozone-induced dissociation (OzID)
and collision-induced dissociation (CID) for the assignment of sites
of unsaturation and sn-positions in glycerolipids.
A miniature ozone generator was developed, which can be operated at
a relatively high pressure. By maintaining high-concentration ozone
inside the linear ion trap, OzID efficiency was significantly improved
for the identification of CC locations in unsaturated lipids,
with reaction times as short as 10 ms. Finally, the miniature OzID
MS system was applied to the analysis of CC locations and sn-positions of lipids from biological samples. Direct sampling
and fast detection of changes in phospholipid isomers were demonstrated
for the rapid discrimination of breast cancer tissue samples, showing
the potential of the miniature OzID MS system for point-of-care analysis
of lipid isomer biomarkers in complex samples
Light-Up Nonthiolated Aptasensor for Low-Mass, Soluble Amyloid‑β<sub>40</sub> Oligomers at High Salt Concentrations
Herein,
a light-up nonthiolated aptasensor was developed for low-mass,
soluble amyloid-β<sub>40</sub> oligomers (LS-Aβ<sub>40‑O</sub>). Au nanoparticles (AuNP) were employed as colorimetric probes,
and the nonthiolated aptamers (Apt) were adsorbed on AuNP surfaces,
acting as binding elements for LS-Aβ<sub>40‑O</sub>.
The aggregation of AuNPs was induced when Apt-modified AuNPs (Apt@AuNPs)
were under high-salt conditions. However, upon the addition of LS-Aβ<sub>40‑O</sub> into the Apt@AuNP solution, the salt tolerance
of the AuNPs was greatly enhanced. Further studies confirmed that
the formed LS-Aβ<sub>40‑O</sub>–Apt complex attached
onto the AuNP surfaces via interactions between LS-Aβ<sub>40‑O</sub> and Au, which led to electrostatic and steric stabilization of the
AuNPs under high-salt conditions. On the basis of this outcome, a
sensitive light-up nonthiolated aptasensor for LS-Aβ<sub>40‑O</sub> was achieved with a detection limit of 10.0 nM and a linear range
from 35.0 to 700 nM in a 175 mM NaCl solution. Cerebrospinal-fluid
(CSF) samples from healthy persons and Alzheimer’s disease
(AD) patients were successfully distinguished by using this proposed
method. The concentrations of LS-Aβ<sub>40‑O</sub> in
the CSF of AD patients were of nanomolar grade, but there was no detectable
LS-Aβ<sub>40‑O</sub> in those of the healthy persons.
This work provides a new insight into the interaction between Apt@AuNPs
and Aβ<sub>40‑O</sub> and also develops a simple, rapid,
highly selective and sensitive, and applicable method for LS-Aβ<sub>40‑O</sub> detection in real CSF samples, which is significant
for the diagnosis of AD
Distribution of the GGGGCC repeats size in SCA3/MJD patients and controls.
<p>There was no significant difference in the distribution of the GGGGCC repeats length between SCA3/MJD patients and controls.</p
Demographic information and average number of repeats between SCA3/MJD patients and controls.
<p><sup>a</sup> x <sup>2</sup> test.</p><p><sup>b</sup> t-tests.</p><p><sup>c</sup> Mann-Whitney U test.</p><p>Demographic information and average number of repeats between SCA3/MJD patients and controls.</p
Frequencies of C9orf72 genotypes.
<p>A presents the frequencies in SCA3/MJD patients. B presents the frequencies in controls.</p
Analysis of the GGGGCC Repeat Expansions of the <i>C9orf72</i> Gene in SCA3/MJD Patients from China
<div><p>Neurodegenerative disorders are a heterogeneous group of chronic progressive diseases and have pathological mechanisms in common. A certain causative gene identified for a particular disease may be found to play roles in more than one neurodegenerative disorder. We analyzed the GGGGCC repeat expansions of <i>C9orf72</i> gene in patients with SCA3/MJD from mainland China to determine whether the <i>C9orf72</i> gene plays a role in the pathogenesis of SCA3/MJD. In our study, there were no pathogenic repeats (>30 repeats) detected in either the patients or controls. SCA3/MJD patients with intermediate/intermediate or short/intermediate genotype (short: <7 repeats; intermediate: 7-30 repeats) of the GGGGCC repeats had an earlier onset compared with those with short/short genotype. The presence of the intermediate allele of the GGGGCC repeats in the patients decreased the age at onset by nearly 3 years. Our study firstly demonstrate that the development of SCA3/MJD may involve some physiological functions of the <i>C9orf72</i> gene and provide new evidence to the hypothesis that a specific mutation identified in one of the neurodegenerative disorders may be a modulator in this class of diseases.</p></div
Additional file 1: of Shanghai cognitive intervention of mild cognitive impairment for delaying progress with longitudinal evaluation-a prospective, randomized controlled study (SIMPLE): rationale, design, and methodology
Description of neuropsychological battery. Here is the description of neuropsychological assessments used in in the SIMPLE study, including their versions, scores and clinical significance. (DOCX 35 kb