Rewiring cis-2-butene-1,4-dial mediated urinary metabolomics fingerprints of short-term exposure to furan.

Furan represents one of the dietary-sourced persistent organic pollutants and thermal processing contaminants. Given its widespread occurrence in food and various toxicological effects, accurately assessing furan exposure is essential for informing public health risks. Furan is metabolized to a reactive primary product, cis-2-butene-1,4-dial (BDA) upon absorption. Some of the resulting BDA-derived metabolites have been proposed as potential exposure biomarkers of furan. However, the lack of quantification for recognized and feasible furan biomarkers has hampered the development of internal exposure risk assessment of furan. In this study, we employed reliable non-targeted metabolomics techniques to uncover urinary furan metabolites and elucidate their chemical structures. We characterized 8 reported and 11 new furan metabolites derived from the binding of BDA with glutathione (GSH), biogenic amines, and/or amino acids in the urine of male rats subjected to varying doses of furan. Notably, a mono-GSH-BDA adduct named cyclic GSH-BDA emerged as a highly prospective specific biomarker of furan exposure, as determined by an ultrahigh-performance liquid chromatography-tandem mass spectrometry method. Cyclic GSH-BDA demonstrated a robust mass spectrometry ion response intensity and exhibited evident time- and dose response. Additionally, we conducted a comprehensive profiling of the kinetics of potential furan biomarkers over time to capture the metabolic dynamics of furan in vivo. Most urinary furan metabolites reached peak concentrations at either the first (3 h) or second (6 h) sampling time point and were largely eliminated within 36 h following furan treatment. The present study provides novel insights into furan metabolism and sheds light on the biomonitoring of furan exposure.

Adversarial Attack and Defense in Breast Cancer Deep Learning Systems.

Deep-learning-assisted medical diagnosis has brought revolutionary innovations to medicine. Breast cancer is a great threat to women's health, and deep-learning-assisted diagnosis of breast cancer pathology images can save manpower and improve diagnostic accuracy. However, researchers have found that deep learning systems based on natural images are vulnerable to attacks that can lead to errors in recognition and classification, raising security concerns about deep systems based on medical images. We used the adversarial attack algorithm FGSM to reveal that breast cancer deep learning systems are vulnerable to attacks and thus misclassify breast cancer pathology images. To address this problem, we built a deep learning system for breast cancer pathology image recognition with better defense performance. Accurate diagnosis of medical images is related to the health status of patients. Therefore, it is very important and meaningful to improve the security and reliability of medical deep learning systems before they are actually deployed.

Assessing human exposure to phthalate esters in drinking water migrated from various pipe materials and water filter elements during water treatments and storage.

Plastic water-supply pipes and filter element are frequently used in municipal water supply systems. Leaching of phthalate esters (PAEs) from these pipes and filter elements to drinking water has become a common concern among the public. In this study, the migrations of 16 phthalate esters (PAEs) in seven different kinds of water-supply product materials were investigated. Di-n-butyl phthalate (DBP) had the highest detection frequency of 54.4% in the water leaching samples of various water supply pipes and water filter elements samples, followed by Diisobutyl phthalate (DIBP, 46/90, 51.1%). The maximum detected concentration level for di(2-ethylhexyl) phthalate (DEHP), diethyl phthalate (DEP), and DBP in the leaching experiment was below the regulatory limit values of 8 µg/L, 300 µg/L, and 3 µg/L for each compound in China standards for drinking water quality. The increasing of the water temperature, the lower pH of the water, and the increasing of the leaching time will increase the migration of PAEs from plastic pipes into water. The chronic daily intake of children aged < 1-12 years to PAEs through drinking water was higher than the rest of the population groups. Carcinogenic risks (CR) of DEHP via drinking water were neglectable for most groups of people, while for young children with age of 1-2 years old, the CR is an acceptable risk.

[Rapid determination of bisphenols in surface water by modified QuEChERS-ultra performance liquid chromatography-tandem mass spectrometry].

Chromatography combined with mass spectrometry is the most commonly used detection technology, and it offers the advantages of high sensitivity and high selectivity. However, the contents of bisphenols (BPs) in water samples are at the ng/L level. Even if the BPs contents are determined by mass spectrometry, the samples must be pretreated and enriched. A quick, easy, inexpensive, effective, rugged, and safe technique (QuEChERS) can offer advantages such as cost effectiveness and time efficiency. The application of QuEChERS is currently extended to the analysis of contaminants in food and water samples. In this work, QuEChERS coupled with ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) was proposed for the determination of eight BPs in surface water. Method optimization was carried out in terms of process efficiency (PE), which included the matrix effect (ME) and extraction recovery (RE). First, the water samples were extracted with 10 mL ethyl acetate and cleaned with 50 mg primary secondary amine (PSA) and 50 mg graphitized carbon black (GCB). Then, the organic layer was collected and evaporated to dryness under nitrogen flow (40 ℃). Finally, the extracts were redissolved in 0.5 mL of a methanol-water (1∶1, v/v) mixture and subjected to UPLC-MS/MS analysis. Chromatographic separation was accomplished on a Waters ACQUITY UPLC BEH C18 column (100 mm×2.1 mm, 1.7 µm) with gradient elution. Methanol and 0.1 mmol/L ammonium bicarbonate aqueous solution were used as the mobile phases. The eight BPs were analyzed by MS/MS with negative electrospray ionization (ESI-) and in the multiple reaction monitoring (MRM) mode. The matrix matching external standard method was used for quantitative determination. The eight compounds could be analyzed within 8 min. Under the optimized conditions, the calibration curves showed good linearities for the eight BPs, and the coefficients of determination (R2) were greater than 0.9990. The limits of detection (LODs, S/N=3) and limits of quantification (LOQs, S/N=10) were in the ranges of 0.1-2.3 ng/L and 0.3-6.1 ng/L, respectively. The average recoveries of the eight BPs in river water samples were 78.8%-116.6%, and the corresponding relative standard deviations (RSDs) were 1.8%-9.0% (n=6). This method was applied to the analysis of BPs pollution in Guangyuan section of Jialing river and its tributaries, and widespread pollution was confirmed. The detection rate of BPA was 100% with a content of 6.15-90.03 ng/L, and the detection rate of BPS was 91%, with the contents being in the range not detected (nd) to 4.63 ng/L. The method established in this study allowed for the rapid enrichment and purification of the eight BPs in water. With its advantages of simplicity, rapidness, high sensitivity, and low cost, the method can be used for the rapid determination of trace BPs in surface water such as lake water and river water.

Severe Metabolic Acidosis and Hyperammonemia Induced by the Concomitant Use of Acetazolamide and Aspirin in a Patient With Impaired Renal Function.

BACKGROUND: Acetazolamide is contraindicated in patients undergoing dialysis and should be used with caution in patients with chronic kidney disease (CKD). Here, we evaluate the effect of the concomitant use of aspirin by patient with CKD using acetazolamide. CASE REPORT: A 63-year-old man with CKD and multimorbidity presented at our Emergency Department (ED) with general weakness and dyspnea for 4 days. Work-up at the ED revealed severe metabolic acidosis and hyperammonemia, which were initially considered signs of sepsis due to an elevated C-reactive protein level and pyuria. However, subsequent blood work indicated hyperchloremic acidosis with low lactate levels. After reviewing his medical history, we suspected the concomitant use of acetazolamide and aspirin as the etiology. Weakness, acidosis, and hyperammonemia were resolved after the patient discontinued acetazolamide. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: Severe acidosis can be life threatening. Acetazolamide is known for causing mild metabolic acidosis, except in patients with severely impaired renal function. Here, we present a patient with mildly impaired renal function and concomitant aspirin use who developed severe metabolic acidosis and hyperammonemia after being prescribed acetazolamide. Regardless of the severity of the disease, patients with CKD should avoid taking acetazolamide concomitantly with aspirin.

Multilocus phylogeny and cryptic diversity of white-toothed shrews (Mammalia, Eulipotyphla, Crocidura) in China.

BACKGROUND: Crocidura, the most speciose mammalian genus, occurs across much of Asia, Europe and Africa. The taxonomy of Chinese representatives has been studied primarily based on cursory morphological comparisons and their molecular phylogenetic analyses remain unexplored. In order to understand the phylogeny of this group in China, we estimated the first multilocus phylogeny and conducted species delimitation, including taxon sampling throughout their distribution range. RESULTS: We obtained one mitochondrial gene (cytb) (~ 1, 134 bp) and three nuclear genes (ApoB, BRCA1, RAG1) (~ 2, 170 bp) for 132 samples from 57 localities. Molecular analyses identified at least 14 putative species that occur within two major well-supported groups in China. Polyphyletic C. wuchihensis appears to be composed of two putative species. Two subspecies, C. rapax rapax and C. rapax kurodai should be elevated to full species status. A phylogenetic tree based on mitochondrial gene from Asian Crocidura species showed that the C. rapax rapax is embedded within C. attenuata, making the latter a paraphyletic group. Three strongly supported undescribed species (C. sp.1, C. sp.2 and C. sp.3) are revealed from Zada County of Tibet (Western China), Hongjiang County of Hunan Province (Central China) and Dongyang County of Zhejiang Province (Eastern China), Motuo County of Tibet, respectively. The divergence time estimation suggested that China's Crocidura species began to diversify during the late Pliocene (3.66 Ma) and the Early Pleistocene (2.29 Ma), followed by a series of diversifications through the Pleistocene. CONCLUSIONS: The cryptic diversity found in this study indicated that the number of species is strongly underestimated under the current taxonomy. We propose that the three undescribed species should be evaluated using extensive taxon sampling and comprehensive morphological and morphometric approaches. Climate change since the late Pliocene and the uplift of the Qinghai-Tibet Plateau may result in the diversification and speciation of China's Crocidura species. In short, the underestimated diversity underlines the need for a taxonomic revision of Chinese Crocidura species.

Development of a Multiresidue Method for Endocrine-Disrupting Pesticides by Solid Phase Extraction and Determination by UHPLC-MS/MS from Drinking Water Samples.

A rapid and efficient method based on solid phase extraction and liquid chromatography-tandem mass spectrometry was validated, allowing the determination of the endocrine-disrupting herbicides (acetochlor, alachlor, amitrole and atrazine), fungicides (carbendazim, triadimefon, penconazole and propiconazole), and insecticides (carbaryl and carbofuran) in drinking water. Low method detection limits (0.01-0.64 ng/L) and method quantification limits (0.03-2.13 ng/L) were obtained with satisfactory recoveries and precision for the endocrine-disrupting pesticides. The method was applied for real drinking water samples collected in the area of the city of Hangzhou (Zhejiang, China); the results showed that carbendazim, atrazine and acetochlor were detected in the drinking water samples and acetochlor was the most detected analyte.

Early Renal-Protective Effects of Remote Ischemic Preconditioning in Elderly Patients with Non-ST-Elevation Myocardial Infarction (NSTEMI).

BACKGROUND With the wide clinical application of angiography, contrast-enhanced nephropathy (CIN) has become the third-leading cause of acute kidney injury (AKI). Remote ischemic preconditioning (RIPC) is a non-fatal ischemia-reperfusion injury that can provide protection against lethal ischemia-reperfusion. This study aimed to assess the effect of RIPC on CIN in elderly patients with non-ST-elevation myocardial infarction (NSTEMI). MATERIAL AND METHODS Patients were randomly divided into 2 groups with 119 patients in each group treated with interventional therapy. Patients in the RIPC group received distal ischemic preconditioning 2 h before contrast exposure, while patients in the control group received a sham RIPC procedure. Incidence of CIN was the primary outcome. Changes in creatinine, NGAL, and KIM-1 after contrast administration were secondary outcomes. RESULTS CIN occurred in a total of 27 (12.3%) patients, including 12 (10.1%) in the RIPC group and 15 (15.1%) in the control group (P=0.329). RIPC treatment significantly reduced the levels of NGAL (P=0.024) and KIM-1 (P=0.007) at 12 h after contrast administration, suggesting RIPC treatment reduces sub-clinical renal damage. Subgroup analysis revealed that significant reduction of KIM-1 and NGAL by RIPC, mainly occurring in patients with a Mehran risk score of 6-10. CONCLUSIONS Although RIPC did not significantly reduce CIN incidence in elderly patients with NSTEMI, the application of more sensitive biomarkers - NGAL and KIM-1 - indicated a reduction of sub-clinical renal damage by RIPC, especially in the early stage of injury. As a simple and well-tolerated method, RIPC may be a potentially feasible option to prevent CIN.

Adipose tissue-derived stem cells in combination with xanthan gum attenuate osteoarthritis progression in an experimental rat model.

The current study explored the efficacy of an intra-articular (IA) injection of allogeneic adipose tissue-derived stem cells (ADSCs) combined with xanthan gum (XG) in a rat osteoarthritis (OA) model. We confirmed that XG significantly inproved proliferation of ADSCs in a dose dependent manner in vitro. The rat OA model was induced by an anterior cruciate ligament transection (ACLT), and at 4 weeks after surgery, rats were divided into four groups: the XG-ADSCs group, the ADSCs group, the XG group and the phosphate-buffered saline (PBS) group. A single dose of 1 × 106 allogeneic ADSCs suspended in 1% XG, ADSCs suspended in PBS, 1% XG alone or PBS alone was injected into the OA joint of rats in the respective treatment groups. Rats were sacrificed at 8 weeks after surgery. Treatment outcomes were evaluated by weight-bearing control of the hind limbs, gross morphological analysis, histological analysis and specific staining of articular cartilage, and measurement of inflammatory factors in synovial fluid. For the rats in the XG-ADSC-s and ADSCs-treated groups, the weight-bearing percentage of the right hind limb was significantly increased compared to that in the PBS group and was sustained over 4 weeks. However, the positive effect in the XG-ADSCs group was significantly greater than that in the ADSCs group. For the rats in the XG group, the efficacy decreased during the third week after surgery. The articular cartilage was relatively normal in the XG-ADSCs group, and moderate degeneration was observed in the ADSCs and XG groups. ADSCs and XG-ADSC treatments significantly decreased the concentrations of IL-1ß, TNF-α, MMP-3 and MMP-13 in synovial fluid; however, the attenuating effect of the XG-ADSCs treatment was significantly enhanced compared with that of the ADSCs treatment alone. These results indicate that a single IA injection of allogeneic ADSCs combined with XG efficiently attenuated OA progression with a therapeutic effect that was significantly greater than that of either ADSCs or XG alone. IA injection of XG-ADSCs might be an effective treatment for OA in humans.

Culture-expanded allogenic adipose tissue-derived stem cells attenuate cartilage degeneration in an experimental rat osteoarthritis model.

Mesenchymal stem cell (MSC)-based cell therapy is a promising avenue for osteoarthritis (OA) treatment. In the present study, we evaluated the efficacy of intra-articular injections of culture-expanded allogenic adipose tissue-derived stem cells (ADSCs) for the treatment of anterior cruciate ligament transection (ACLT) induced rat OA model. The paracrine effects of major histocompatibility complex (MHC)-unmatched ADSCs on chondrocytes were investigated in vitro. Rats were divided into an OA group that underwent ACLT surgery and a sham-operated group that did not undergo ACLT surgery. Four weeks after surgery mild OA was induced in the OA group. Subsequently, the OA rats were randomly divided into ADSC and control groups. A single dose of 1 × 106 ADSCs suspended in 60 µL phosphate-buffered saline (PBS) was intra-articularly injected into the rats of the ADSC group. The control group received only 60 µL PBS. OA progression was evaluated macroscopically and histologically at 8 and 12 weeks after surgery. ADSC treatment did not cause any adverse local or systemic reactions. The degeneration of articular cartilage was significantly weaker in the ADSC group compared to that in the control group at both 8 and 12 weeks. Chondrocytes were co-cultured with MHC-unmatched ADSCs in trans-wells to assess the paracrine effects of ADSCs on chondrocytes. Co-culture with ADSCs counteracted the IL-1ß-induced mRNA upregulation of the extracellular matrix-degrading enzymes MMP-3 and MMP-13 and the pro-inflammatory cytokines TNF-α and IL-6 in chondrocytes. Importantly, ADSCs increased the expression of the anti-inflammatory cytokine IL-10 in chondrocytes. The results of this study indicated that the intra-articular injection of culture-expanded allogenic ADSCs attenuated cartilage degeneration in an experimental rat OA model without inducing any adverse reactions. MHC-unmatched ADSCs protected chondrocytes from inflammatory factor-induced damage. The paracrine effects of ADSCs on OA chondrocytes are at least part of the mechanism by which ADSCs exert their therapeutic activity.

Analysis of Numerous Androgen Disruptors in Fish by Gas Chromatography Tandem Mass Spectrometry.

An improved analytical method was developed for the simultaneous quantification of numerous androgen disruptors-vinclozolin, dichlorodiphenyltrichloroethanes (DDTs), hexachlorocyclohexanes, chlordane, heptachlor, dieldrin, endrin, and aldrin-in fish, followed by GC with tandem MS (MS/MS). Extraction, cleanup, and MS/MS parameters of analytes were optimized. The LOQs of the analytes ranged from 0.3 to 3.7 µg/kg. Reasonable recoveries (73.7-119.2%) were demonstrated at different spike levels with RSDs lower than 12.2%. This method was applied for the analysis of the target analytes in fish samples sold in Hangzhou, China, and DDTs were found to be the predominant contaminants in fish samples.

Determination of a broad spectrum of endocrine-disrupting pesticides in fish samples by UHPLC-MS/MS using the pass-through cleanup approach.

We describe a new methodology for the simultaneous determination of the endocrine-disrupting herbicides (acetochlor, alachlor, amitrole, and atrazine), fungicides (carbendazim, triadimefon, penconazole, and propiconazole), and insecticides (carbaryl and carbofuran) in fish samples followed by high-performance liquid chromatography with tandem mass spectrometry. Samples were extracted and purified using the pass-through cleanup approach. The recoveries of the pesticides were in the range 71.8-116.5%, with relative standard deviations lower than 15.28%. Limits of quantitation were in the range of 0.03-2.50 µg/kg. Validation results on linearity, accuracy, and precision, as well as on application to the analysis of the endocrine-disrupting pesticides in 20 fish samples, demonstrated the applicability to screen the presence of pesticides in fish.

Icariin stimulates the proliferation of rat bone mesenchymal stem cells via ERK and p38 MAPK signaling.

Bone mesenchymal stem cells (BMSCs) are able to differentiate into multi types of lineages, so they have been widely applied in the stem cell transplantation. The BMSCs are usually needed to be expanded before transplantation due to their limited content in bone marrow. It has recently been reported that Icariin (ICA), a major constituent of flavonoids from the Chinese medical herb Epimedium brevicornum Maxim, promotes the proliferation of various types of differentiated cells. However, whether ICA can enhance BMSCs proliferation and the possible underlying mechanisms are still unknown. After being isolated and purified from rat bone marrow, cultured BMSCs are stimulated with different concentrations of ICA. The cytotoxicity of ICA is evaluated by the Cell Counting Kit-8 (CCK-8) assay method and the ICA optimal concentration for BMSCs proliferation is determined at 320 µg/L. Our work reveals that ICA induces an obvious phosphorylation of ERK and p38 kinases in BMSCs, no matter serum exists or not. Inhibition of ERK or p38 MAPK signaling by their specific inhibitors PD98059 or SP600125, respectively, not only prevents the activation of these kinases, but also attenuates cell proliferation induced by ICA. Furthermore, the downstream transcription factors of MAPK pathway, Elk1, Stat3, c-Myc and Fos, are also monitored by RT-PCR, and our results show that among them, Elk1 and c-Myc are significantly upregulated after ICA treatment. Taken together, our results demonstrate that ICA promotes the proliferation of rat BMSCs through activating ERK and p38 MAPK signaling which further leads to upregulation of their downstream transcription factors Elk1 and c-Myc. Our work provides a novel effective way to expand the content of BMSCs in vitro, which casts light on clinical applications of stem cell transplantation in the future.

Poly-γ-glutamate from Bacillus subtilis inhibits tyrosinase activity and melanogenesis.

Poly-γ-glutamate (γ-PGA) has been considered as one of the most promising biomaterials with a wide range of applications, but there has been no report that directly shows the anti-tyrosinase and anti-melanogenesis properties of γ-PGA. In the present study, we investigated the inhibitory effects of γ- PGA with low molecular weight (Mw; lγ-PGA) and high Mw (hγ-PGA) on mushroom tyrosinase and murine tyrosinase activities and on melanogenesis in B16 melanoma cells. First, we showed that both lγ-PGA and hγ-PGA could effectively inhibit mushroom tyrosinase activities including monophenolase and diphenolase activities in a dose-dependent manner. Second, both lγ-PGA and hγ-PGA showed strong anti-tyrosinase activity and anti-melanogenesis in B16 melanoma cells. Third, both lγ-PGA and hγ-PGA inhibited forskolin-induced tyrosinase activity and melanogenesis by decreasing the levels of intracellular reactive oxygen species and nitric oxide while increasing the catalase activity in B16 cells. This is the first report on the anti-melanogenesis effect of γ-PGA, which suggests that γ-PGA could have a potential in the cosmetic skin whitening business, therapeutic applications and the food industry.

Changes of thyroid hormone levels and related gene expression in zebrafish on early life stage exposure to triadimefon.

In this study, zebrafish was exposed to triadimefon. Thyroid hormones levels and the expression of related genes in the hypothalamic-pituitary-thyroid (HPT) axis, including thyroid-stimulating hormone (TSH-beta), deiodinases (dio1 and dio2) and the thyroid hormone receptor (thraa and thrb) were evaluated. After triadimefon exposure, increased T4 can be explained by increased thyroid-stimulating hormone (TSH-beta). The conversion of T4 to T3 (deiodinase type I-dio1) was decreased, which reduced the T3 level. Thyroid hormone receptor beta (thrb) mRNA levels were significantly down-regulated, possibly as a response to the decreased T3 levels. The overall results indicated that triadimefon exposure could alter gene expression in the HPT axis and that mechanisms of disruption of thyroid status by triadimefon could occur at several steps in the synthesis, regulation, and action of thyroid hormones.