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ObjectiveTo apply high performance liquid chromatography-inductively coupled plasma mass spectrometry （HPLC-ICP/MS） to the analysis of five forms of selenium ［Se（Ⅵ）， Se（Ⅳ）， SeCys， MeSeCys， and SeMet］ in livestock meat.MethodsThe selenium species were extracted using the ultrasonic-assisted enzyme method， with C18 reversed-phase column （250 mm×4.6 mm， 5 μm） as the analytical column， 10 mmol/L citric acid and 5 mmol/L sodium hexane sulfonate （pH=4.0， containing 1% methanol） as the mobile phase， and an injection volume of 20 μL.ResultsFour selenium forms were separated in 7 min， with correlation coefficients greater than 0.999， indicating good linearity. The detection limits of Se（Ⅵ）， SeCys， MeSeCys， and SeMet ranged from 0.000 3-0.002 mg/kg. The spiked recoveries of selenium-enriched pork at three concentrations （low， medium， and high） ranged from 80.0% to 103.3%， with a relative standard deviation of less than 6.8%. Certified Reference Material ERM® BC210 revealed values within the standard range.ConclusionThe developed method was suitable for determining Se（Ⅵ） SeCys， MeSeCys， and SeMet in livestock meat. The meat was found to mainly contain SeMet and small amounts of MeSeCys and SeCys.

BACKGROUND Selenium is an essential trace element and a typical bifunctional element that can affect human health if consumed in insufficient or excessive amounts. The biological activity of selenium depends not only on its intake level but also on its chemical speciation. Selenium comes in various speciation and is divided mainly into inorganic and organic selenium. Inorganic selenium includes selenate [Se(Ⅵ)] and selenite [Se(Ⅳ)], and organic selenium mainly includes selenocysteine (SeCys2), selenomethionine (SeMet), and methylselenocysteine (MeSeCys). It has been found that organic selenium has high bioactivity and bioavailability. At present, while the nutritional effects of selenium are drawing more and more attention, it is very important to analyze and study the different speciation of selenium in food. Since the analysis of selenium speciation is closely related to the sample matrix, the extraction efficiency and stability of different selenium speciation are also related to many factors. At present, the analysis method of selenium speciation in food is still in the research stage. Broccoli is rich in nutrients, such as protein, flavonoids, polyphenols, and vitamins, and is widely loved by people because it contains many kinds of thioglucosides and has a strong ability to gather selenium, which has antioxidant and anti-cancer medical values. Therefore, the analysis and study of selenium speciation in broccoli is of some significance. OBJECTIVES To establish a method for the determination of Se(Ⅵ), Se(Ⅳ), SeCys2, MeSeCys, and SeMet in commercial broccoli by high performance liquid chromatography-inductively coupled plasma-mass spectrometry (HPLC-ICP-MS). METHODS Firstly, the chromatographic conditions were selected by examining the separation and sensitivity of Se(Ⅵ), Se(Ⅳ), SeCys2, MeSeCys, and SeMet on a Hamilton PRP-X100 anion column with 40mmol/L diammonium hydrogen phosphate (pH=5 with 1% methanol) as the mobile phase and on a ZORBAX SB-Aq C18 reversed-phase column with 10mmol/L citric acid plus 5mmol/L sodium hexane-sulphonate (pH=4 with 1% methanol) as the mobile phase. Secondly, the sample pretreatment conditions were optimized, including the selection of extraction reagents, the amount of extraction reagents, and extraction time. Four extraction reagents (ultrapure water, Tris-HCl buffer solution, proteinase XIV and complex proteinase) were selected for optimization. The effect of proteinase XIV concentration on the extraction was investigated by adding 2, 4, 6, and 8mg/mL proteinase XIV to broccoli samples with selenium content of 0.81mg/kg (calculated as Se). The effect of adding 6mL, 10mL, 12mL, and 15mL of Tris-HCl buffer solution on the extraction was compared. The extraction time of the samples also had a great influence on the extraction efficiency of the selenium speciation. The effects of four extraction times of 1h, 3h, 5h and 7h on the extraction were compared. RESULTS The ZORBAX SB-Aq C18 separation system was used in this study because of the short analysis time and high sensitivity of each selenium speciation. Protease XIV was the most effective extraction reagent for selenium; therefore proteinase XIV was chosen as the extraction reagent. The concentration of selenium speciation increased with the concentration of proteinase XIV. The maximum concentration of selenium speciation was reached when the concentration of proteinase XIV was 6mg/mL. It was reported that the use of Tris-HCl buffer solution with proteinase XIV at appropriate pH conditions could further improve the extraction efficiency and maintain the stability of selenium speciation. The volume of Tris-HCl buffer increased, the extraction efficiency of each selenium speciation gradually increased and then decreased, and the final selection of Tris-HCl buffer solution addition was 12mL. A longer extraction time would help to increase the extraction effect, but too long an enzymatic digestion time would also cause a decrease in the stability of SeMet and SeCys2. To ensure high extraction efficiency and reduce the conversion of selenium speciation, an extraction time of 3h was preferred. After optimization and selection, the final analysis method was determined as follows: weighing a certain amount of broccoli sample into 12mL of Tris-HCl (pH=7.4, containing 6mg/mL proteinase XIV) at a concentration of 100mmol/L, vortexing and mixing, and then sonicating at 37℃ for 3h. After centrifugation, the extraction were eluted with 10mmol/L citric acid and 5mmol/L sodium hexane sulfonate (pH=4 with 1% methanol) on ZORBAX SB-Aq C18 reversed-phase column. ICP/MS was used for analysis and determination.This method can achieve effective separation and determination of five selenium speciation within 8 minutes. The linearity range of the method was 0.3-100.0μg/L, with linear correlation coefficients (r) greater than 0.999. The detection limits of Se(Ⅳ), Se(Ⅵ), MeSeCys, and SeMet were within the range of 1.2-6.0μg/kg (calculated as Se). The standard recovery tests were carried out on broccoli samples at low, medium, and high concentration. The recoveries of these four selenium speciation, Se(Ⅵ), Se(Ⅳ), MeSeCys and SeMet, were 81.9%-105.3% with relative standard deviations (RSD) less than 5%. The method established in this study was used to determine SeMet in the EU-certified reference material (ERM BC210a, wheat flour), and the measured value of SeMet was within the range of its standard values.More than 20 commercially available broccoli samples collected from different regions of China were analyzed and determined. The results showed that the selenium speciation in commercially available broccoli was mainly MeSeCys, with small amounts of Se(Ⅵ), Se(Ⅳ), and SeMet, and also a small amount of unknown selenium-containing compounds was also present.Two problems identified in the methodological study were explored. (1) The effect of proteinase XIV dosage on the stability of SeCys2 was investigated by adding 1, 2, 4, and 6mg/mL of proteinase XIV to SeCys2 standard solution, respectively. The results showed that as the concentration of proteinase XIV increased, the signal value of SeCys2 gradually decreased and the signal value of three unknown peaks gradually increased. At the same time, the recovery of SeCys2 in broccoli samples decreased to 10%. Based on the above conditions, it is assumed that the content of proteinase XIV and the matrix of broccoli samples affect the stability of SeCys2.(2) Three different broccoli samples were selected for Se(Ⅳ) standard recovery tests: fresh commercially available broccoli samples, freeze-dried powder of commercially available broccoli, and freeze-dried powder of broccoli fortified with Se(Ⅳ) selenium fertilizer. A certain amount of the above three samples was added with Se(Ⅳ) standard solution and 100mmol/L Tris-HCl (pH=7.4, containing 6mg/mL of proteinase XIV). The determination was then carried out according to the proposed analytical method and the mean recoveries of the three samples were found to be 81.1%, 69.5% and 1.53%, respectively. The Kruskal-Wallis rank sum test showed that the recoveries of Se(Ⅳ) were significantly different among the three samples (p < 0.05). Previous investigations have found that phenolic substances can affect the stability of Se(Ⅳ) and that the addition of selenium fertilizer during the growth of broccoli can change the phenolics. Based on the above, it is assumed that the presence of phenolics in broccoli samples may affect the determination of Se(IV). CONCLUSIONS A method for the determination of Se(Ⅳ), Se(Ⅵ), MeSeCys, and SeMet in commercially available broccoli by HPLC-ICP-MS is established by selecting and optimizing the sample pretreatment and analytical conditions. The Tris-HCl buffer solution containing proteinase XIV is chosen for the extraction of samples.It is found that the stability of SeCys2 is affected by the concentration of proteinase XIV and broccoli samples matrix. It is hypothesized that the presence of large amounts of phenolics in the samples can affect the determination of Se(Ⅳ) for reasons to be further explored.

Abstract Background Emerging evidence of immunological dysfunction have been described in endometriosis. Dendritic cells (DCs), one of the main antigen-presenting cells, are specialized in the initiation and modulation of the adaptive immune response. Emerging studies demonstrated both endometrial and circulating differences in DCs populations in women with endometriosis. However, the role and mechanism of peritoneal DCs in endometriosis is still unclear. The present study was undertaken to explore the features of peritoneal DCs in the pathogenesis of endometriosis. This study is beneficial to further clarify the cause of endometriosis and provide a new insight into the medical treatment for endometriosis. Methods The study included 12 women with endometriosis and 11 women without endometriosis. The C57BL6 mouse model of endometriosis was established by intraperitoneal injection of endometrial segments. The peritoneal DCs of endometriosis patients and mouse models were analyzed by fluorescence associated cell sorting (FACS) examination. Results Increased cell density of peritoneal DCs were observed in endometriosis patients. Moreover, the proportion of mature DCs (mDCs, CD80highCD1alow cells) in the peritoneal DCs was lower whereas the proportion of immature DCs (iDCs, CD80lowCD1ahigh cells) was increased in endometriosis patients. Similarly, the cell density of peritoneal DCs in murine models increased immediately after the injection of endometrial tissues and reached the highest level at 14 days. In addition, the proportion of mDCs (CD11chighCD80high cells) in the peritoneal DCs decreased immediately after the injection of endometrial tissues and then increased with the time until 42 days, but still lower than the control group. In contrast, the proportion of iDCs (CD11chighCD80low cells) in the peritoneal DCs showed the opposite dynamic changes. However, after treated with LPS, the mDCs proportion was significantly increased, leading to lower volume and weight of the endometriosis lesions. Conclusions Increased level of peritoneal DCs facilitated the pathogenesis of endometriosis lesions, especially in the early stage of the disease. Furthermore, peritoneal DCs maturation played an important role in the development of endometriosis.

The total selenium content of selenium-enriched agricultural products was determined by inductively coupled plasma mass spectrometry after microwave digestion. The total selenium content in the tested samples ranged from 27.9 μg/kg to 13.6 mg/kg. High performance liquid chromatography–inductively coupled plasma mass spectrometry was employed to determine selenite and selenate in selenium-enriched rice, tea, and garlic. The separation of inorganic and organic selenium was realized within 15 min by using 40 mmol/L diammonium phosphate (pH 5.0) and 60 mmol/L diammonium phosphate (pH 6.0) as the mobile phase with gradient elution. Selenite and selenate were isolated by ultrasonic assisted extraction at 78 °C for 30 min with 0.1 mol/L potassium hydroxide as the extraction solution. The detection limits were 2.5 and 5 μg/kg for selenite and selenate, respectively. The relative standard deviation was less than 5.5%. Recoveries of inorganic selenium were between 88.2% and 113.0%. The proposed method was successfully applied for the determination of inorganic selenium as well as total selenium in selenium-enriched rice, tea, and garlic. The results showed that inorganic selenium in natural selenium-enriched agricultural products is primarily present in selenite composing no more than 20% of total selenium. [ABSTRACT FROM AUTHOR]

The aim of the present study was to investigate the impact and mechanism of high mobility group box 1 (HMGB1) on the regulation of cell migration and invasion in A2780/DDP cisplatin-resistant ovarian cancer cells. After transfecting small interfering (si)RNA-HMGB1 into A2780/DDP cells, Transwell migration and invasion assays were conducted to assess alterations in the cell migratory and invasive abilities. Additionally, western blotting analyses were performed to examine changes in HMGB1, phosphorylated (p)-GSK-3β, GSK-3β, E-cadherin and vimentin expression levels. The results of the present study demonstrated that the migratory and invasive abilities of A2780/DDP cells were significantly higher compared with those of A2780 cells. Additionally, the expression levels of HMGB1, p-GSK-3β and the mesenchymal phenotype marker, vimentin, in A2780/DDP cells were significantly elevated relative to the levels in A2780 cells. Conversely, the expression level of the epithelial phenotype marker, E-cadherin, was markedly decreased compared with that in A2780 cells. Following transfection of A2780/DDP cells with siRNA-HMGB1, there was a significant reduction in the rate of cell migration and invasion. Simultaneously, the expression levels of HMGB1, p-GSK-3β and vimentin were downregulated while the level of E-cadherin was upregulated. It was therefore concluded that the high expression of HMGB1 in A2780/DDP cells enhanced the cell migration and invasion abilities by facilitating epithelial to mesenchymal transition via GSK-3β. [ABSTRACT FROM AUTHOR]

Objective: To investigate the pro-apoptotic effects of Indirubin, a traditional Chinese medicine, on ovarian cancer SKOV3 cell line and to explore its underlying mechanisms., Methods: Ovarian cancer SKOV3 cells were divided into a control group (cells cultured normally) and an experimental group (cells cultured in medium containing Indirubin). SKOV3 cells at the logarithmic phase were treated with Indirubin at various concentrations. Cell proliferation was assessed using the Cell Counting Kit-8 (CCK-8) assay and 3-(4,5)-dimethylthiahiazo (-z-y1)-3,5-di-phenytetrazoliumromide (MTT) assay, while apoptosis was detected by flow cytometry, TdT-mediated dUTP Nick-End Labeling (TUNEL) staining, and immunofluorescence. Transcriptome sequencing was conducted to screen for apoptosis-related factors. qPCR and western blot were used to detect the mRNA and protein expression on added of molecules related to mitochondrial permeability transition pores., Results: MTT assay showed that Indirubin inhibited the growth of SKOV3 cells in both plate and sphere cultures, with IC 50 values of 3.003 μM (plate culture) and 4.253 μM (sphere culture), respectively. Indirubin showed a lower inhibitory concentration than cisplatin (IC 50 3.687 μM in plate culture and 7.023 μM in sphere culture), and its effect was comparable to adriamycin. Flow cytometry revealed an increase in apoptosis rates in SKOV3 cells treated with Indirubin. Transcriptome sequencing indicated significant changes in the transcription of various apoptosis-related genes, particularly those involved in the mitochondrial apoptosis pathway, such as Bcl-2-associated X protein (Bax) and Bcl2 associated agonist of cell death (Bad). After Indirubin treatment, the mRNA and protein expression levels of mitochondrial channel-related genes Cyclophilin D (CyPD), adenine nucleotide translocator 1 (ANT1), and voltage-dependent anion channel (VADC) were significantly elevated (all P < 0.05). By regulating the mitochondrial membrane permeability through the Bcl-2 family members, Indirubin promoted apoptosis in SKOV3 cells., Conclusion: Indirubin inhibits the proliferation and promotes the apoptosis of ovarian cancer cells, exerting an anti-tumor effect. Its pro-apoptotic action is closely related to the mitochondrial apoptosis pathway., Competing Interests: None., (AJTR Copyright © 2024.)

Objective: To investigate the clinical characteristics and prognostic factors in patients with endometriosis-associated ovarian cancer., Methods: In this study, we retrospectively analyzed the medical records of 135 ovarian cancer patients admitted to our hospital from January 2016 to January 2018. Based on the presence of concomitant endometriosis (EMs), the patients were divided into two groups: the Endometriosis-Associated Ovarian Cancer (EAOC) group (n=64) and the non-EAOC (NEAOC) group (n=71). We compared the clinical characteristics of the two groups. Additionally, in the EAOC group, we followed up with patients for 5 years, categorized them into the survival group (n=40) and the deceased group (n=24) based on their prognosis, and conducted univariate and multivariate logistic regression analyses to identify influencing factors., Results: In comparison to the NEAOC group, patients in the EAOC group exhibited higher rates of menopause occurrence, pathological stages I-II, vaginal bleeding, and history of cesarean section, with statistical significance (P < .05). They also had a lower incidence of dysmenorrhea, lymph node metastasis, and abdominal distension, as well as an earlier age of onset, all of which were statistically significant (P < .05). There were no statistically significant differences (P > .05) between the two groups in terms of parity, gravidity, tumor diameter, abdominal pain incidence, and body mass index. Based on prognosis, the patients were categorized into a survival group (n=40) and a deceased group (n=24). Comparison between the two groups showed statistically significant differences (P < .05) in terms of postoperative residue, epithelial-mesenchymal transition, and lymph node metastasis. In contrast, there were no statistically significant differences (P > .05) in terms of tumor laterality, histological type, tumor stage, differentiation degree, and vaginal bleeding. The variables with P < .05 were assigned as independent variables, with the prognosis of death as the dependent variable. Multivariate logistic regression analysis revealed that epithelial-mesenchymal transition and lymph node metastasis were independent risk factors for mortality in EAOC patients (P < .05)., Conclusion: Clinical characteristics of EAOC patients show significant differences, with epithelial-mesenchymal transition and lymph node metastasis being identified as independent adverse prognostic factors associated with poor outcomes in EAOC patients. However, this study has limitations such as a relatively small sample size, and further research is therefore necessary.

Background: Long non-coding RNAs (lncRNAs) have been confirmed to play vital roles in tumorigenesis. LncRNA MYU has recently been reported as an oncogene in several kinds of tumors. However, MYU's expression status and potential involvement in ovarian cancer (OC) remain unclear. In this study, we explored the underlying role of MYU in OC. Methods and results: The expression of MYU was upregulated in OC tissues, and MYU's overexpression was significantly correlated with the FIGO stage and lymphatic metastasis. Knockdown of MYU inhibited cell proliferation in SKOV3 and A2780 cells. Mechanistically, MYU directly interacted with miR-6827-5p in OC cells; HMGA1 is a downstream target gene of miR-6827-5p. Furthermore, MYU knockdown increased the expression of miR-6827-5p and decreased the expression of HMGA1. Restoration of HMGA1 expression reversed the influence on cell proliferation caused by MYU knockdown. Conclusion: MYU functions as a ceRNA that positively regulates HMGA1 expression by sponging miR-6827-5p in OC cells, which may provide a potential target and biomarker for the diagnosis or prognosis of OC., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Wang, Zheng, Wang, Chen and Chen.)

Objective: To understand the distribution characteristics of 46 elements in drinking water in Ankang area of Shanxi Province., Methods: A total of 46 elements in drinking water samples collected in Ankang area during dry and wet seasons in 2020 were determined by inductively coupled plasma mass spectrometry(ICP-MS). According to the "drinking water hygiene standards"(GB 5749-2022) and "food safety national standards". the 46 elements were classified As general chemical indexes(Al, Mn, Fe, Cu, Zn), toxicological indexes(Cr, As, Cd, Hg, Pb, Ba, B, Mo, Ni, Sb, Be, Ag, Tl), new reference indexes(U, V), and major elements(K, Ca, N) A, Mg), trace elements(Li, Co, Se, Sr, Sn) and rare earth elements(Sc, Y, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Th) were analyzed and described., Results: The maximum values of Al and Fe in drinking water in Ankang area were 1.21 and 0.98 mg/L, exceeding the limits of 0.2 and 0.3 mg/L. In dry season, the median content of Fe in drinking water of different water sources was higher in groundwater than in surface water. The Al and Fe of surface water were higher than that of groundwater in wet season. The toxicological indexes all met the standard requirements, and there was no significant difference among districts and counties. The median content of Na in drinking water of different water sources was higher in groundwater than in surface water, while Mg, K and Ca were higher in surface water than in groundwater. The maximum value of the newly added reference index U was 0.015 mg/L lower than the limit standard 0.03 mg/L, and the maximum value of V was 0.019 mg/L higher than the limit standard 0.01 mg/L, but the median of both indexes were low. The median content of Li in drinking water of different water sources was that surface water was higher than groundwater, while Se and Sr were higher in groundwater than surface water. The maximum content of Se was 0.016 mg/L in Ziyang County, and Sr content was generally higher. The content of rare earth elements was low, mostly below the detection., Conclusion: The drinking water quality in Ankang area is excellent and rich in strontium. However, the general chemical indexes Al, Fe and the newly added appendix index V in some sampling points exceed the limit standard, so supervision and monitoring should be strengthened.

Objective: A method was established to determine mercury in seven sorts of disinfectant by water-bath-microwave digestion-atomic fluorescence spectrometry., Methods: The samples of disinfectant were preliminary digestion by water-bath at 90℃and then dissolved by microwave according to the temperature programmed. The mercury ions in the digested solution reacted with reductant to generate the mercury vapour which were measured the fluorescence intensity by the atomic fluorescence spectrometer., Results: The linear range was from 0- 15 μg / L and the correlation coefficient was 0. 9995. The detection limit of this method was 0. 17 μg / kg. The precision of the method was less than4. 2% and the spiked recoveries of high, medium and low concentrations were between87%- 105%., Conclusion: This method possesses several advantages including less interference, high accuracy, good reproducibility and high sensitivity. It is suitable for the current determination of mercury in the seven sorts of disinfectant.