Colorimetric Sensors for Chemical and Biological Sensing Applications.

Colorimetric sensors have been widely used to detect numerous analytes due to their cost-effectiveness, high sensitivity and specificity, and clear visibility, even with the naked eye. In recent years, the emergence of advanced nanomaterials has greatly improved the development of colorimetric sensors. This review focuses on the recent (from the years 2015 to 2022) advances in the design, fabrication, and applications of colorimetric sensors. First, the classification and sensing mechanisms of colorimetric sensors are briefly described, and the design of colorimetric sensors based on several typical nanomaterials, including graphene and its derivatives, metal and metal oxide nanoparticles, DNA nanomaterials, quantum dots, and some other materials are discussed. Then the applications, especially for the detection of metallic and non-metallic ions, proteins, small molecules, gas, virus and bacteria, and DNA/RNA are summarized. Finally, the remaining challenges and future trends in the development of colorimetric sensors are also discussed.

Icariin restrains NLRP3 inflammasome-mediated Th2 immune responses and ameliorates atopic dermatitis through modulating a novel lncRNA MALAT1/miR-124-3p axis.

CONTEXT: Atopic dermatitis (AD) is a common inflammatory skin disease characterized with hyperactivation of type 2 T helper (Th2) immune responses. Icariin is a flavonoid glucoside with anti-inflammatory activities, which has been used to treat multiple diseases. OBJECTIVE: The present study investigates the underlying mechanisms by which icariin regulates Th2 responses and AD development. MATERIALS AND METHODS: BALB/c mice were induced by DNFB to establish AD models, and injected with or without 10 mg/kg icariin for 2 weeks (i.p., daily). CD4+T cells were induced by Th2 condition to simulate AD in vitro, and also treated with or without 100 µM icariin. RESULTS: Icariin ameliorated AD-like skin lesion, manifested as a significant decrease in dermatitis scores (from 8.00 ± 1.00 to 3.67 ± 0.58), serum IgE levels (from 3119.15 ± 241.81 to 948.55 ± 182.51 ng/mL), epidermal thickness (from 93.86 ± 4.61 to 42.67 ± 2.48 µm) and infiltration of mast cells (from 60.67 ± 3.21 cells to 36.00 ± 2.65 cells). Also, icariin inactivated NLRP3 inflammasome, inhibited Th2 skewing, reduced lncRNA MALAT1 expression, but elevated miR-124-3p expression in vivo and in vitro. MALAT1 increased NLRP3 expression through targeting miR-124-3p. Knockdown of MALAT1 repressed NLRP3 inflammasome activation and mitigated Th1/Th2 imbalance in Th2-conditioned CD4+T cells, whereas both MALAT1 overexpression and miR-124-3p inhibition ablated the inhibitory effects of icariin on Th2 immune responses. DISCUSSION AND CONCLUSIONS: The findings further improve our understanding of the mechanism by which icariin affects AD progression, and highlights the potential of icariin in the treatment of AD.

Suppressing Sulfite Dimerization at a Polarized Gold Electrode/Water Solution Interface for High-Quality Gold Electrodeposition.

Solid/liquid interfacial structure occupies great importance in chemistry, biology, and materials. In this paper, by combining EC-SERS study and DFT calculation, we reveal the adsorption and dimerization of sulfite (SO32-) at a gold electrode/water solution interface, and establish an adsorption displacement strategy to suppress the dimerization of sulfite. At the gold electrode/sodium sulfite solution interface, at least two layers of SO32- anions are adsorbed on the electrode surface. As the applied potential shifts negatively, the adsorption strength of the first SO32- layer is weakened gradually and then is dimerized with the second orientated SO32- layer to form S2O52-, and S2O52- is further reduced to S2O32-. After hydroxyethylene disphosphonic acid (HEDP) is introduced to the gold electrode/sodium sulfite solution interface, the second oriented SO32- layer is replaced by a HEDP coadsorption layer. This results in the first layer of SO32- being desorbed directly without any structural transformation or chemical reaction as the potential shifts negatively. The suppression of sulfite dimerization by HEDP is more clear at the gold electrode/gold sulfite solution interface owing to the electroreduction of gold ions. Furthermore, the electrochemical studies and electrodeposition experiments show that as the sulfite dimerization reaction is suppressed, the electroreduction of gold ions is accelerated, and the deposited gold coating is bright and dense with finer grains.

[Effect of Dendrobii officinalis superfine powder on overeating greasy-induced metabolic hypertension in rats].

Dendrobii officinalis, with a definite effect of nourishing Yin and clearing heat, has been a folk habit for drinking after being mixed with water. Because its superfine powder has the advantages of high dissolution and convenient drinking, we observed the effect of D. officinalis superfine powder on metabolic hypertension model rats and its possible mechanism in this experiment, which can be used as a reference for its clinical application for hypertension. The overeating greasy-induced metabolic hypertension model was established with high-fat, high-sugar and high-purine diet. These rats were orally administered with 400 mg·kg~(-1) and 200 mg·kg~(-1) of D. officinalis superfine powder for 20 consecutive weeks. During this period, blood pressure, blood lipid, blood glucose, insulin and other related indexes of glucose and lipid metabolism were monitored; the levels of lipopolysaccharide(LPS), C-reactive protein(CRP), interleukin 6(IL-6) and other inflammatory mediators were measured; the levels of nitric oxide(NO) and endothelin-1(ET-1) were detected, and the histomorphological and ultrastructural changes of aorta were observed. In addition, the expression of LPS/TLR4 pathway-related molecules in aorta was determined. The results showed that long-term administration of D. officinalis superfine powder significantly reduced the levels of systolic blood pressure(SBP), diastolic blood pressure(DBP) and mean arterial pressure(MBP) in metabolic hypertension model rats, decreased the levels of total cholesterol(TC), triglyceride(TG), low density lipoprotein cholesterol(LDL-c), glucose(Glu), and insulin(INS) levels in blood, increased the contents of high density lipoprotein cholesterol(HDL-c),decreased the LPS, CRP, IL-6 and ET-1 levels in blood and increased NO content. Furthermore, it improved the abnormality of aortic histomorphology and endothelial ultrastructure, and inhibited the protein expression of TLR4, myeloid differentiation factor(MyD88), IL-6, interleukin-1 ß(IL-1ß), and tumor necrosis factor-α(TNF-α) as well as mRNA expression of TNF-α and IL-1ß in aorta. In conclusion, D. officinalis superfine powder may improve the abnormal function and structure of blood vessels by inhibiting the activation of LPS/TLR4 pathway, thus playing a role against metabolic hypertension.

[Effect of Yunkang Oral Liquid on preventing LPS-induced abortion and regulating immune tolerance in mice].

To investigate the effect of Yunkang Oral Liquid on preventing lipopolysaccharide(LPS)-induced abortion and regulating immune tolerance in mice,sixty normal ICR mice were randomly divided into normal group,model group,Yunkang Oral Liquid high,middle and low dose groups and progesterone group.Abortion model was established by tail vain injection of LPS(0.1µg/mouse)on the 7th day of pregnancy.Since the first day of pregnancy,the same volume of distilled water,Yunkang Oral Liquid at the dose of 36,18 and 9 m L·kg~(-1)·d~(-1),and progesterone at the dose of 0.038 g·kg~(-1)·d~(-1)were given in corresponding groups.The mice were sacrificed at the 9th day of pregnancy,and the embryo loss of each group was calculated.The levels of Th1 type cytokines(TNF-α,IFN-γ)and Th2 type cytokines(IL-4,IL-10)in uterus homogenate were detected by ELISA.HE staining was performed to examine the histopathological changes in the decidua.The expression levels of CD14,F4/80 in macrophages of uterus were detected by immunohistochemistry.Western blot was used to investigate the protein expression of TLR4,MyD88 and NF-κB in uterine decidua.In our study,all Yunkang Oral Liquid groups could significantly reduce the embryo absorption rate of mice,while high dose group can significantly increase the levels of IL-10 and IL-4;both medium and high dose groups can significantly decrease TNF-α,and IFN-γlevelsin the uterus of model mice,reduce the protein expression of NF-κB,MyD88 and TLR4 in uterine decidua tissue.Various treatment groups could reduce the counts of F4/80,CD14 macrophages and decrease expression area in uterine tissue.Our results showed that Yunkang Oral Liquid could prevent LPS-induced abortion,and the mechanism may be associated with inhibiting the TLR4/MyD88/NF-κB signaling pathway and regulating the balance of Th1/Th2 immune factors,which could improve the endometrial receptivity of mice,and promote the development of decidua and implantation of embryo.

[Investigate optimum conditions and determinate changes of ß-glucosidase activity in Scrophularia root under different drying conditions].

To explore the optimum conditions of ß-glucosidase activity in Scrophularia root by using pNPG method. The extraction conditions and reaction conditions (such as extraction liquid type, reaction system, reaction time, temperature, and substrate concentration) were screened by using monofactorial experiment and homogeneous design. Then the changes of ß-glucosidase activity in Scrophularia root were detected at the drying temperature of 40-100 ℃. The results showed that citric acid phosphate buffer had better extraction effect, and the maximum absorbance produced by enzymatic reaction was present at 50 ℃ environment after reaction for 30 min. Homogeneous design experiment determined that the optimal conditions were as follows: optimal extraction liquid pH 7.0; enzymatic reaction system pH 6.0; substrate concentration 20 mmol•L⁻¹. The change of enzyme activity was affected by drying temperature and water loss rate. In the drying temperature of 60-100 ℃, the enzyme activity was reduced rapidly with the increase in water loss rate, while the activity was seen even with 0% of water at 40 and 50 ℃. This study has laid the theoretical foundation for research of hydrolysis mechanism of iridoid glycosides and optimum drying process.

[A quantitative method for simultaneous assay of seven active ingredients with one marker in Scrophularia ningpoensis root].

To establish a new quantitative method for simultaneous determination of multi-components in Scrophularia root by using high performance liquid chromatography (HPLC) and validate its feasibilities．Meanwhile,using catalpol as one chemical reference substance to establish the relative correct factors and relative retention values of aucubin,harpagide,acteoside,angoroside C,harpagoside and cinnamic acid．Then using the quantitative analysis of multi-components by single-marker (QAMS)model,the six analytes can be quantitatively determined in Scrophularia root．The method was evaluated by comparison of the quantitative results to external standard method．No significant differences were observed between the quantitative results of the two methods．The obtained RCFs were credible．It is feasible and suitable to evaluate the quality of Scrophularia root.

Morinda officinalis extract exhibits protective effects against atopic dermatitis by regulating the MALAT1/miR-590-5p/CCR7 axis.

BACKGROUND: Atopic dermatitis (AD) is a chronic inflammatory skin disease with a genetic predisposition, and the traditional Chinese medicine Morinda officinalis and its roots are characterized with anti-inflammatory effects and have been used for the treatment of various disease. However, it is still largely unknown whether Morinda officinalis extract (MOE) can be used for the treatment of AD. OBJECTIVES: In our study we aimed to determine whether MOE could ameliorate 2,4-dinitrochlorobenzene (DNCB)-induced AD and elucidate molecular mechanisms. METHODS: We established an AD mouse model by using DNCB. Skin pathological analysis and ELISA assay were used to detect the effect of MOE on the inflammation of AD model mouse skin and the expression changes of inflammatory factors, and further functional verification was performed in TNF-α/IFN-γ-induced HaCaT cells. RESULTS: Our in vivo experiments confirmed that MOE remarkably reduced DNCB-induced AD lesions and symptoms, such as epidermal and dermal thickness and mast cell infiltration and inflammatory cytokines secretion in the mice models. In addition, the underlying mechanisms by which MOE ameliorated AD had been uncovered, and we verified that MOE inhibited MALAT1 expression in AD, resulting in attenuated expression of C-C chemokine receptor type 7 (CCR7) regulated by MALAT1-sponge miR-590-5p in a competing endogenous RNA (ceRNA) mechanisms-dependent manner, thereby inhibiting TNF-α/IFN-γ-induced cellular proliferation and inflammation.

A novel system for predicting liver histopathology in patients with chronic hepatitis B.

There is currently a lack of reliable, reproducible, and easily applied methods for assessing changes in liver histology in patients in the gray zone phase of chronic hepatitis B (CHB). Therefore, we aimed to develop a novel predictive scoring system to detect significant liver histological changes in these patients.A total of 388 patients in the gray zone phase of CHB who underwent liver biopsy were divided into a training group and a validation group, and their clinical and routinely available laboratory parameters were analyzed using univariate analysis, Spearman correlation analysis, and logistic modeling. A novel scoring system, termed the Significant Histological Model (SHM), was constructed using logistic modeling. The diagnostic accuracy of our novel scoring system was evaluated by the receiving operating characteristic (ROC) method, sensitivity, specificity, and positive and negative predictive values (NPVs).We established the novel SHM scoring system using serum aspartate transaminase (AST), platelet counts (PLTs), albumin (ALB), and hepatitis B virus (HBV) DNA (log10 IU/mL) levels. The area under the ROC curve of the SHM scoring system was 0.763 in the training group and 0.791 in the validation group. For patients with a score of -1.0 or less and no significant histological changes, the sensitivity was 78.9%, specificity was 51.5%, positive predictive value (PPV) was 46.4%, and NPV was 82.0%. In the validation set, the sensitivity, specificity, PPV, and NPV were 80.0%, 66.6%, 56.3%, and 86.2%, respectively.This novel scoring system using AST, PLT, ALB, and HBV DNA (log10 IU/mL) levels identifies patients in the gray zone phase of CHB with and without histological changes with a high degree of accuracy. Here, we provide the experimental basis for the initiation of clinical antiviral treatment without the need for liver biopsy.