Discrimination rancidity degree of infant formula rice flour based on Headspace Solid-Phase Microextraction combined with Gas Chromatography-Mass Spectrometry as an alternative to sensory evaluation.

To mitigating the serious threat of harmful volatile substances to the health of infants, an alternative method of odor evaluation were proposed based on Headspace solid-phase microextraction (HS-SPME) combined with Gas Chromatography-Mass Spectrometry (GC-MS) to discriminate the degree of rancidity of infant formula rice flour (IFRF). Inspectors can simply calculate the rancidity degree of infant formula rice flour according to the regression equation based on the concentration of rancidity markers. The results showed that the joint application of OPLS-DA, molecular sensory experiments, and unsaturated fatty acids (UFAs) degradation experiments could successfully recognize the rancidity markers without collinearity in multiple linear regression analysis. The rancidity markers curve fitting was helpful for the establishment of multivariate regression model of rancidity grading. The model had an accuracy of more than 92.90% by the verification of odor evaluation. The application of the model to investigate the market IFRF samples showed that about 3% of the samples collected in the experiment were unsuitable for infant feeding. Therefore, the established model was considered to be a robust and less workload method to replace the olfactory evaluation method for discriminating the rancidity degree of IFRF.

PRDX1 stimulates non-small-cell lung carcinoma to proliferate via the Wnt/ß-Catenin signaling.

BACKGROUND: Previous studies have shown that PRDX1 is upregulated in some types of malignant tumors. The role of PRDX1 in non-small-cancer lung carcinoma (NSCLC) remains unclear. This study aims to identify the role of PRDX1 in influencing in-vitro biological functions of NSCLC and the molecular mechanism. METHODS: We collected 50 cases of fresh NSCLC and adjacent non-tumoral tissues for detecting differential expressions of PRDX1 by quantitative real-time polymerase chain reaction (qRT-PCR). Survival time of NSCLC patients, defined as the period from the operation to the latest follow-up or death due to recurrence or metastasis, was recorded for assessing the relationship between PRDX1 and prognosis in NSCLC. Using lentivirus transfection, PRDX1 level was downregulated in NSCLC cells. Subsequently, proliferative and apoptotic abilities, and expression levels of vital genes in the Wnt/ß-Catenin signaling were examined. Finally, the significance of activated Wnt/ß-Catenin signaling during PRDX1-regulated NSCLC proliferation was explored. RESULTS: Using GEPIA database and NSCLC tissues we collected, PRDX1 was detected to be upregulated in NSCLC samples than controls. PRDX1 level was related to tumor staging and prognosis in NSCLC. Knockdown of PRDX1 attenuated proliferative ability and stimulated apoptosis in NSCLC. Protein levels of Wnt5A was downregulated in H1299 and SPC-A1 cells with PRDX1 knockdown. Overexpression of ß-Catenin enhanced proliferative ability and inhibited apoptosis in NSCLC cells with PRDX1 knockdown. CONCLUSIONS: PRDX1 is upregulated in NSCLC samples, and linked to tumor staging and prognosis. It stimulates NSCLC to proliferate by activating the Wnt/ß-Catenin signaling.

Effective and repeatable chromatographic separation of 5 nucleotides in infant formula milk powder by ion-pair high-performance liquid chromatography-ultraviolet.

A robust method using HPLC-UV was developed to improve the accuracy and repeatability of a quantitative method to detect 5 nucleotides (cytidine-monophosphate, uridine monophosphate, adenosine monophosphate, guanine monophosphate, and inosine monophosphate) in infant formulas. The results showed that efficient separation could not be achieved without strict conditions. The proposed method displayed a strong linear relationship (R2 > 0.9999) of single nucleotide in infant formula milk powder in the range of 10 to 1,000 mg/kg, a steady recovery (80.0% ∼110.0%) with relative standard deviation from 0.5% to 3.5%, under strict conditions of hydrophilic C18 column with di-isopropyl at 62.5 ± 2.5°C (± standard deviation), 0.65 ± 0.1 mg/mL tetrabutylammonium bisulfate, and mobile phase of pH of 2.75 ± 0.02. By applying this method on a series of milk products in the Chinese market, we found a few of them exceeded the legal limits of nucleotides.

Hypoglycemic effects and mechanism of different molecular weights of konjac glucomannans in type 2 diabetic rats.

Konjac glucomannan (KGM) is a hypoglycemic polysaccharide with a wide range of molecular weights. But study on hypoglycemic effects of KGMs relate to molecular weight is limited. In this study, KGMs with high and medium molecular weights, and the degraded KGMs were analyzed with physicochemical properties, hypoglycemic effects and mechanisms. Results showed that as the molecular weight KGMs decreased, the viscosity decreased, molecular flexibility increased, while chemical groups, crystal structures and main chains showed little change. KGMs with medium molecular weights (KGM-M1, KGM-M2) showed better effects on increasing body weight, decreasing levels of fasting blood glucose, insulin resistance, total cholesterol and low density lipoprotein cholesterol, and enhancing integrity of pancreas and colon, than KGMs with high or low molecular weights (KGM-H, KGM-L) in type 2 diabetic rats. Mechanism analysis suggested that KGM-M1 and KGM-M2 had higher antioxidant and anti-inflammatory activities on elevating superoxide dismutase, decreasing malondialdehyde and tumor necrosis factor-α levels. Moreover, KGM-M1 and KGM-M2 increased gut microbiota diversity, Bacteroidetes/Firmicutes ratio and Muribaculaceae, decreased Romboutsia and Klebsiella, and improved 6 diabetic related metabolites. Combined, KGM-M1 and KGM-M2 showed higher hypoglycemic effects, due to regulatory activities of antioxidant, anti-inflammatory, intestinal microbiota, and relieved metabolic disorders.

Modulating Linker Composition of Haptens Resulted in Improved Immunoassay for Histamine.

Histamine (HA) is an important food contaminant generated during food fermentation or spoilage. However, an immunoassay for direct (derivatization free) determination of HA has rarely been reported due to its small size to induce the desired antibodies by its current hapten-protein conjugates. In this work, despite violating the classical hapten design criteria which recommend introducing a linear aliphatic (phenyl free) linker into the immunizing hapten, a novel haptens, HA-245 designed and synthesized with a phenyl-contained linker, exhibited significantly enhanced immunological properties. Thus, a quality-improved monoclonal antibody (Mab) against HA was elicited by its hapten-carrier conjugates. Then, as the linear aliphatic linker contained haptens, Hapten B was used as linker-heterologous coating haptens to eliminate the recognition of linker antibodies. Indirect competitive ELISA (ic-ELISA) was developed with a 50% inhibition concentration (IC50) of 0.21 mg/L and a limit of detection (LOD) of 0.06 mg/L in buffer solution. The average recoveries of HA from spiked food samples for this ic-ELISA ranged from 84.1% and 108.5%, and the analysis results agreed well with those of referenced LC-MS/MS. This investigation not only realized derivatization-free immunoassay for HA, but also provided a valuable guidance for hapten design and development of immunoassay for small molecules.

Nutritional Composition and Antioxidant Properties of the Fruits of a Chinese Wild Passiflora foetida.

The aim of this work was to evaluate the main nutrients and their antioxidant properties of a Chinese wild edible fruit, Passiflora foetida, collected from the ecoregion of Hainan province, China. The analytical results revealed that P. foetida fruits were rich in amino acids (1097 mg/100 g in total), minerals (595.75 mg/100 g in total), and unsaturated fatty acids (74.18 g/100 g in total fat). The lyophilized powder of edible portion contained the higher polyphenols content than the inedible portion powder. The UPLC-Q-TOF-MSE analysis of the extractable and non-extractable phenolics indicated the presence of 65 compounds including 39 free phenolics, 14 insoluble-glycoside-phenolics, and 22 insoluble-ester-phenolics. In addition, the non-extractable phenolics obtained by alkali hydrolysis showed significant antioxidant activities by/through DPPH and ABTS radical scavenging. These findings of P. foetida fruits, for the first time, suggest that these polyphenol-rich fruits may have potential nutraceutical efficacies.

Visual detection of formaldehyde by highly selective fluorophore labeling via gold(III) complex-mediated three-component coupling reaction.

A novel method for visual detection of formaldehyde with excellent selectivity via a gold(iii) complex-mediated three-component coupling reaction of resin-linked sterically bulky amines and fluorescent alkynes has been developed.

[The cause and efficacy of benign tracheal stenosis].

OBJECTIVE: To analysis the causes of benign tracheal stenosis and evaluate the curative effect of intraluminal bronchoscopic treatment. METHODS: 158 patients with benign tracheal stenosis in our hospital from September 2005 to September 2012 were collected to retrospectively analysis the causes and clinic features of tracheal stenosis. Interventional treatments through bronchoscopy were used to treat the benign tracheal stenosis and the curative effects were evaluated. RESULTS: 158 cases of benign tracheal stenosis were recruited to our study, 69.6% of them were young and middle-aged. The main causes of benign tracheal stenosis were as follows: secondary to postintubation or tracheotomy in 61.4% (97/158), tuberculosis in 16% (26/158), benign tumor in 5.1% (8/158) and other 27 cases. 94.3% patients improved in symptoms with alleviation immediately after bronchoscopic treatment, the average tracheal diameter increased form (4.22 ± 2.06) mm to (10.16 ± 2.99) mm (t = 21.48, P < 0.01), dyspnea index decreased from 2.29 ± 0.75 to 0.63 ± 0.67 (t = 19.85, P < 0.01). The recurrence rate in 1 and 3 month after interventional treatment were 38.3% and 26.8%, respectively. CONCLUSION: The cases of benign tracheal stenosis were increasing year by year. The most common cause of benign tracheal stenosis was postintubation and tracheotomy. Interventional treatments through bronchoscopy is effective in treating benign tracheal stenosis, but repeated interventional procedures may be required to maintain the favorable long-term effects.