Colorimetric Xylenol Orange: A Long-Buried Aggregation-Induced Emission Dye and Restricted Rotation for Dual-Mode Sensing of pH and Metal Ions.

As the third largest class of dyes in the world, triphenylmethane dyes are widely applied in colorimetric sensing. However, triphenylmethane dyes are commonly nonfluorescent, which limits their sensing applications. It is worthwhile to study the fluorescence off/on control of triphenylmethane dyes and promote the applications of triphenylmethane dyes in sensing technology.

Non-canonical signaling initiated by hormone-responsive G protein-coupled receptors from subcellular compartments.

G protein-coupled receptors (GPCRs), the largest family of membrane receptors in the mammalian genomes, regulate almost all known physiological processes by transducing numerous extracellular stimuli including almost two-thirds of endogenous hormones and neurotransmitters. The traditional view held that GPCR signaling occurs exclusively at the cell surface, where the receptors bind with the ligands and undergo conformational changes to recruit and activate heterotrimeric G proteins. However, with the application of advanced biochemical and biophysical techniques, this conventional model is challenged by the elucidation of spatiotemporal GPCR activation with the evidence that receptors can signal from subcellular compartments to exhibit various molecular and cellular responses with physiological and pathophysiological relevance.

In situ synthesis of luminescent dsDNA-Cu NCs stained with a dsDNA-lighted fluorophore for rapid and stable detection of histamine in food.

Poisonous histamine is accumulated in stale meat and fermented foods. The rapid and stable detection of histamine is essential for food safety. Herein, a ratiometric fluorometric method for histamine detection was designed through in situ preparing double-stranded DNA‑copper nanoclusters (dsDNA-Cu NCs) stained with 4',6-diamidino-2-phenylindole (DAPI).

A highly sensitive SERS substrate of porous membrane-Ag NPs for kidney cancer detection.

Background: The substrate employed in surface-enhanced Raman spectroscopy (SERS) constitutes an essential element in the cancer detection methodology. In this research, we introduce a three-dimensional (3D) structured SERS substrate that integrates a porous membrane with silver nanoparticles to enhance SERS spectral signals through the utilization of the aggregation effect of silver nanoparticles. This enhancement is crucial because accurate detection results strongly depend on the intensity of specific peaks in Raman spectroscopy.

An ultrasensitive photoelectrochemical assay for tumor necrosis factor-alpha based on hollow CdS cubes as a signal generator and NiCoO-Au as a signal extinguisher.

Sensitive detection of tumor necrosis factor-alpha (TNF-α) in human serum is beneficial for finding cancer patients early due to overexpressed TNF-α being related to some cancers. Here, a photoelectrochemical (PEC) aptasensor was constructed for ultrasensitive TNF-α assay based on the signal generator of hollow CdS cubes (H-CdS) and the signal extinguishing activity of NiCoO-Au. In this work, compared with traditional solid CdS, H-CdS could greatly promote the PEC signal because its hollow structure could accelerate the separation of photogenerated charges, which also possesses abundant active sites and high light absorption capability.

Xylenol orange-modified CdTe quantum dots as a fluorescent/colorimetric dual-modal probe for anthrax biomarker based on competitive coordination.

Bacillus anthracis spores can make humans infected with vicious anthrax, so it is significant to detect their biomarker 2,6-pyridinedicarboxylic acid (DPA). The development of dual-modal methods for DPA detection that are more flexible in practical applications remains a challenge. Herein, colorimetric xylenol orange (XO) was modified on fluorescent CdTe quantum dots (QDs) for dual-modal detection of DPA through competitive coordination.

Enzyme-free fluorescence determination of uric acid by combining CdTe quantum dots with metal-organic framework for signal amplification.

The composite of CdTe quantum dots (QDs) with ZIF-8 was elaborately designed and synthesized as an enzyme-free fluorescent probe for the sensitive determination of uric acid (UA), based on the fluorescence detection property of CdTe QDs and the signal amplification function of ZIF-8. The structure and feature of the composite were characterized with transmission electron microscopy, scanning electron microscopy, powder X-ray diffraction, and fluorescence spectrometry. With adding UA to the composite, the emission of CdTe QDs reduced due to the inner filter and dynamic quenching effects of UA, and the adsorption ability of ZIF-8 toward UA promoted the response signal of CdTe QDs.

Bifunctional ratiometric fluorescent probe for sensing anthrax spore biomarker and tetracycline at different excitation channels.

Multifunctional fluorescent probes have received increasing attention for the sake of atom economy and high-density integration. Herein, CdTe quantum dots (QDs) modified with Eu were synthesized as the bifunctional ratiometric fluorescent probe for sensing two hazardous substances tetracycline (TC) and anthrax spore biomarker 2,6-dipicolinic acid (DPA) at different excitation channels, based on the discrepant excitation wavelengths of Eu and the fluorescence quenching of CdTe QDs after interaction with them. Both DPA and TC enhanced the red emission of Eu via antenna effect but caused the green emission of CdTe QDs to quench.

CdTe QDs@ZIF-8 composite-based recyclable ratiometric fluorescent sensor for rapid and sensitive detection of chlortetracycline.

The residue problem in animal food products caused by the abuse of chlortetracycline (CTC) is one of the food safety issues that have attracted much attention. Herein, a composite was generated by embedding CdTe quantum dots (QDs) into ZIF-8 for ratiometric fluorescent analysis of CTC. With adding CTC, the green luminescence of CTC appeared under the sensitization effect of Zn in ZIF-8, but the red luminescence of CdTe QDs was reduced by the inner filtration effect of CTC.

A ratiometric fluorescence-scattering sensor for rapid, sensitive and selective detection of doxycycline in animal foodstuffs.

The residue problem of tetracycline antibiotics, especially doxycycline (DC), in animal foodstuffs has attracted much attention. This paper reported ZIF-8 and bovine serum albumin (BSA) as a ratiometric fluorescence-scattering sensor for DC. The mechanism relied on the disassembly of ZIF-8 caused by DC, bringing weakened second-order scattering, and the double fluorescence amplification of DC under ZIF-8 with BSA, inducing enhanced fluorescence.

Use of traditional Chinese medicine as an adjunctive treatment for COVID-19: A systematic review and meta-analysis.

Background: This review aims to evaluate the supportive effects of frequently used traditional Chinese medicine (TCM) for the treatment of coronavirus disease 2019 (COVID-19).

Methods: Five databases were searched through July 7, 2020. Randomized controlled trials investigating the efficacy of TCM for use in the treatment of COVID-19 were included.

Identification and characterization of two novel melanocortin-3 receptor mutations in Chinese obese individuals.

The melanocortin-3 receptor (MC3R) and melanocortin-4 receptor (MC4R), known as neural melanocortin receptors, have been implicated to be critical components of the hypothalamic leptin-melanocortin pathway and related to obesity pathogenesis. In contrast to extensive evidence from physiologic, biological, genetic studies demonstrating that MC4R is a critical regulator in obesity, whether MC3R mutation causes obesity is still controversial. In the present study, we screened for coding variants in the MC3R gene of 176 obese individuals (mean BMI 34.

A Zinc Metal-Organic Framework for Concurrent Adsorption and Detection of Uranium.

Uranium is one of the principal raw materials in the nuclear industry, but if released into the natural environment, it also poses latent health risks to mankind. Therefore, there is an urgent need to develop a strategy that can concurrently detect and adsorb uranium to realize the sustainable development of nuclear power and protect the environment. In this work, a fluorescent zinc-based metal-organic framework () was designed and synthesized for the effective detection and extraction of U(VI).

Gastrin, Cholecystokinin, Signaling, and Biological Activities in Cellular Processes.

The structurally-related peptides, gastrin and cholecystokinin (CCK), were originally discovered as humoral stimulants of gastric acid secretion and pancreatic enzyme release, respectively. With the aid of methodological advances in biochemistry, immunochemistry, and molecular biology in the past several decades, our concept of gastrin and CCK as simple gastrointestinal hormones has changed considerably. Extensive and studies have shown that gastrin and CCK play important roles in several cellular processes including maintenance of gastric mucosa and pancreatic islet integrity, neurogenesis, and neoplastic transformation.

Melanocortin Regulation of Inflammation.

Adrenocorticotropic hormone (ACTH), and α-, β-, and γ-melanocyte-stimulating hormones (α-, β-, γ-MSH), collectively known as melanocortins, together with their receptors (melanocortin receptors), are components of an ancient modulatory system. The clinical use of ACTH in the treatment of rheumatoid arthritis started in 1949, originally thought that the anti-inflammatory action was through hypothalamus-pituitary-adrenal axis and glucocorticoid-dependent. Subsequent decades have witnessed extensive attempts in unraveling the physiology and pharmacology of the melanocortin system.

Therapeutic strategies for diseases caused by loss-of-function mutations in G protein-coupled receptors.

As one of the largest families of cell membrane proteins, G protein-coupled receptors (GPCRs) are involved in regulating almost all physiological processes by transducing extracellular signals into the cytoplasm. Since the first discovery of naturally occurring mutations in Rhodopsin gene in 1990, hundreds of loss-of-function mutations in multiple GPCRs have been identified to be pathogenic for more than 30 diverse human diseases, making these defective receptors important drug targets for personalized medicine. In this review, we aim to elucidate the etiologies of five common inherited diseases caused by six of the most extensively studied GPCRs.

Regulation of prostate cancer by hormone-responsive G protein-coupled receptors.

Regulation of prostate cancer by androgen and androgen receptor (AR), and blockade of AR signaling by AR antagonists and steroidogenic enzyme inhibitors have been extensively studied. G protein-coupled receptors (GPCRs) are a family of membrane receptors that regulate almost all physiological processes. Nearly 40% of FDA-approved drugs in the market target GPCRs.