Chemical warfare simulant-responsive polymer nanocomposites: Synthesis and evaluation

Nanomaterials that undergo a physical change upon chemical warfare agent (CWA) exposure can potentially be used in detectors to warn soldiers of their presence or in fabrics to provide on‐demand protection. In this study, hybrid nanoparticles (NPs) were prepared by grafting a CWA‐responsive polymer from a silicon dioxide (SiO₂) surface using ring opening metathesis polymerization; the covalent functionalization of the polymers on the NP surface was confirmed by gel permeation chromatography, dynamic light scattering, and transmission electron microscopy analysis. The polymer‐grafted SiO₂ NPs were found to undergo a pronounced decrease (approximately 200 nm) in their hydrodynamic radius upon exposure to CWA simulants trifluoroacetic acid and diethyl chlorophosphate in toluene. This decrease in hydrodynamic radius is attributed to the electrophile‐mediated ionization of the triarylmethanol responsive unit and represents a rare example of polycation formation leading to polymer chain collapse. We have ascribed this ionization‐induced collapse to the formation of a favorable stacking interaction between the planar triarylcations. These studies have important implications for the development of breathable fabrics that can provide on‐demand protection for soldiers in combat situations. Keywords: nanocomposites; stimuli-responsive; ROMP; organophosphates; triarylmethanolsDefense Threat Reduction Agency (DTRA) (Contract BA12PHM123

FOXE1 polyalanine tract length screening by MLPA in idiopathic premature ovarian failure

<p>Abstract</p> <p>Background</p> <p>FOXE1 is one of the candidate genes for genetic predisposition to premature ovarian failure (POF) and it contains an alanine tract. Our purpose is to assess the influence of length of the alanine tract of FOXE1 on genetic susceptibility to POF.</p> <p>Methods</p> <p>The group studied consisted of 110 Chinese patients with idiopathic POF and 110 women from normal controls. The polyalanine tract and flanking sequence of FOXE1 was screened using the Multiple Ligation-dependent Probe Amplification (MLPA) technique and directly sequenced.</p> <p>Results</p> <p>Three variants of FOXE1-polyalanine length, containing 12, 14, or 16 alanine residues, and 5 different genotypes were identified. There were significantly lower frequencies of the 14/14 genotypes in cases with POF (X2 = 119.73, P = 0.001), as compared with the controls. The incidence of 16/16 genotypes of FOXE1-polyalanine was significantly higher in patients with POF (X2 = 3.403, P = 0.001) in comparison to the controls. The FOXE1 14 alanine allele was significantly less common in the POF patient group (186/220) than the controls (216/220) (X2 = 25.923, P = 0.0001). The FOXE1 16 alanine allele was significantly more common in the POF patient group (28/220) than the controls (4/220) (X2 = 19.412, P = 0.0001).</p> <p>Conclusion</p> <p>This finding provides evidence that polyalanine repeat expansions in FOXE1 may be responsible for the genetic aetiology of POF in Chinese women.</p

The Accuracy of Near Infrared Autofluorescence in Identifying Parathyroid Gland During Thyroid and Parathyroid Surgery: A Meta-Analysis

ObjectiveWe aim to assess the accuracy of near infrared autofluorescence in identifying parathyroid gland during thyroid and parathyroid surgery.MethodA systematic literature search was conducted by using PubMed, Embase, and the Cochrane Library electronic databases for studies that were published up to February 2021. The reference lists of the retrieved articles were also reviewed. Two authors independently assessed the methodological quality and extracted the data. A random-effects model was used to calculate the combined variable. Publication bias in these studies was evaluated with the Deeks’ funnel plots.ResultA total of 24 studies involving 2,062 patients and 6,680 specimens were included for the meta-analysis. The overall combined sensitivity and specificity, and the area under curve of near infrared autofluorescence were 0.96, 0.96, and 0.99, respectively. Significant heterogeneities were presented (Sen: I2 = 87.97%, Spe: I2 = 65.38%). In the subgroup of thyroid surgery, the combined sensitivity and specificity, and the area under curve of near infrared autofluorescence was 0.98, 0.99, and 0.99, respectively, and the heterogeneities were moderate (Sen: I2 = 59.71%, Spe: I2 = 67.65%).ConclusionNear infrared autofluorescence is an excellent indicator for identifying parathyroid gland during thyroid and parathyroid surgery

Regulation of LYRM1 Gene Expression by Free Fatty Acids, Adipokines, and Rosiglitazone in 3T3-L1 Adipocytes

LYR motif containing 1 (LYRM1) is a novel gene that is abundantly expressed in the adipose tissue of obese subjects and is involved in insulin resistance. In this study, free fatty acids (FFAs) and tumor necrosis factor-α (TNF-α) are shown to upregulate LYRM1 mRNA expression in 3T3-L1 adipocytes. Conversely, resistin and rosiglitazone exert an inhibitory effect on LYRM1 mRNA expression. These results suggest that the expression of LYRM1 mRNA is affected by a variety of factors that are related to insulin sensitivity. LYRM1 may be an important mediator in the development of obesity-related insulin resistance

Detection of micrometastases in peripheral blood of non-small cell lung cancer with a refined immunomagnetic nanoparticle enrichment assay

Fe3O4 particles are currently used as the core of immunomagnetic microspheres in the immunomagnetic enrichment assay of circulating tumor cells (CTCs). It is difficult to further improve the sensitivity of CTC detection or to improve tumor cell-type identification and characterization. In the present study, we prepared immunomagnetic nanoparticles with nanopure iron as the core, coated with anti-cytokeratin 7/8 (CK7/8) monoclonal antibody. These immunomagnetic nanoparticles (IMPs) were used in conjunction with immunocytochemistry (ICC) to establish a refined immunomagnetic nanoparticle enrichment assay for CTC detection in non-small cell lung cancer (NSCLC). The assay was compared with nested reverse transcription polymerase chain reaction (RT-PCR) to detect CK19 mRNA and lung specific X protein (LUNX) mRNA. Human lung adenocarcinoma cell line A549 was used for sensitivity and specificity evaluation. Peripheral blood samples were collected from each group for CTC detection. The average diameter of the immunomagnetic nanoparticles was 51 nm, and the amount of adsorbed antibodies was 111.2 μg/mg. We could detect down to one tumor cell in 5 × 107 peripheral blood mononuclear cells. The sensitivity was consistent with that of nested RT-PCR; however, the false positive rate was significantly reduced. The modified assay combined with ICC did not differ from nested RT-PCR in sensitivity, but it had significantly increased specificity. This approach could, therefore, contribute to identification of micrometastases, re-defining clinical staging, and guiding individual postoperative treatments. The technique shows considerable potential clinical value and further clinical trials are warranted

Single nonmagnetic impurity resonance in FeSe-based 122-type superconductors as a probe for pairing symmetry

We study the effect of a single non-magnetic impurity in A$_{y}$Fe$_{2-x}$Se$_{2}$ (A=K, Rb, or Cs) superconductors by considering various pairing states based on a three-orbital model consistent with the photoemission experiments. The local density of states on and near the impurity site has been calculated by solving the Bogoliubov-de Gennes equations self-consistently. The impurity-induced in-gap bound states are found only for attractive impurity scattering potential, as in the cases of doping of Co or Ni, which is characterized by the strong particle-hole asymmetry, in the nodeless $d_{x^2-y^2}$ wave pairing state. This property may be used to probe the pairing symmetry of FeSe-based 122-type superconductors.Comment: 7 pages, 7 figure

Cucurbit[6]uril-based carbon dots for recognizing l-tryptophan and capecitabine

Fluorescent nitrogen and fluorine doped carbon dots (CDs) were prepared by a hydrothermal method using levofloxacin (LVFX) and cucurbit[6]uril (Q[6]) as the nitrogen and carbon sources, respectively. Decomposition of LVFX occurred at elevated temperature affording N,N′-desethylene levofloxacin hydrochloride (N,N′-DLH). The crystal structure of the resulting inclusion complex N,N′-DLH@Q[6]·[CdCl4]2(H3O)·9H2O was determined, where N,N′-DLH is protonated on each of the terminal nitrogens and the quinone functionality is a quinol which forms an intramolecular hydrogen bond to the carboxylic acid. The synthesized N,N′-DLH containing Q[6]-CDs emitted intense blue fluorescence with high photostability and exhibited stability at high ionic strength. In particular, the original rigid macrocyclic skeletons of these hosts were retained during the fabrication process, which helps in uniquely distinguishing them from other reported CDs. Meanwhile, the performance of the Q[6]-CDs was characterized using fluorescence and NMR spectroscopies. Subsequently, using the obtained Q[6]-CDs, an efficient sensing method for l-tryptophan (l-Trp) and capecitabine (CAP) has been developed based on macrocyclic host-guest chemistry. Under applicable conditions, the detection limits for l-Trp and CAP were calculated to be 5.13 × 10−8 M and 1.48 × 10−8 M, respectively