Analytical Assessment of Bio- and Toxic Elements Distribution in Pu-erh and Fruit Teas in View of Chemometric Approach

Abstract

This study concerns application of flame atomic absorption spectrometry (FAAS) in assessment of macro- and microelement and toxic metal levels (Mg, Ca, K, Na, Mn, Cu, Fe, Zn, Cr, Ni, Co, Cd and Pb) in dark (Pu-erh) and fruit tea leaves and their infusions. Phosphorus was also determined in the form of phosphomolybdate by spectrophotometric method. The reliability of the method was checked using three certified reference materials. The results of analysis were in agreement with the certified values, with analytical recovery ranging from 86 to 113 %. Significant correlations (p < 0.001) were found between concentrations of P, Zn, K, Ni, Fe, Co, Cr, and Pb in Pu-erh tea, whereas in fruit tea, such interdependences were found between Mg, Fe, P, Ni, and Co. Kruskal-Wallis test results have related differences in Pu-erh tea quality as well as technological processing of fruit tea to their mineral composition. In order to characterize tea elemental content, chemometric techniques such as factor analysis (FA) and cluster analysis (CA) were used. Their application allowed on differentiation of samples in view of the fermentation type, technological processing, and overall quality.

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Cerium Oxide-Incorporated Calcium Silicate Coating Protects MC3T3-E1 Osteoblastic Cells from H 2 O 2 -Induced Oxidative Stress

Abstract

Oxidative stress regulates cellular functions in multiple pathological conditions, including bone formation by osteoblastic cells. In this work, the protective effects of cerium oxide (CeO₂)-incorporated calcium silicate (CeO₂-CS) coating on the response of osteoblasts to H₂O₂-induced oxidative stress and the related mechanism were examined. CeO₂ incorporation significantly improved osteoblast viability and reduced cell apoptosis caused by H₂O₂ when compared with the control. H₂O₂-induced reduction of differentiation marker alkaline phosphatase (ALP) was recovered in the presence of the CeO₂-CS coating. The above effects were mediated by the antioxidant effect of CeO₂. The CeO₂-CS coating immersed in 0.1 mM H₂O₂ aqueous solution was able to degrade 64 % of it in 1 week. In addition, CeO₂ incorporation decreased reactive oxygen species (ROS) production and suppressed malondialdehyde (MDA) formation in H₂O₂-treated osteoblasts. Taken together, CeO₂-CS biomedical coatings with antioxidant property would be promising for bone regeneration under oxidative stress.

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The Effects of Copper on Brain Microvascular Endothelial Cells and Claudin Via Apoptosis and Oxidative Stress

Abstract

Many neurodegenerative diseases are related to copper although the effects on brain microvascular endothelial cells (BMECs) are poorly understood. In the present study, a primary BMEC culture model was established to evaluate the effects of copper on brain microvascular endothelial cells and whether claudin-1, claudin-3, claudin-5, and claudin-12 isoforms contribute to apoptosis and intrinsic antioxidant activity. Our results showed that copper ions had dual effects on BMECs by regulating intracellular reactive oxygen species (ROS) levels. Copper levels between 30 and 120 μM could enhance viability and promote proliferation. On the other hand, copper cytotoxicity was a result of apoptosis indicating a redox-independent manner of cell death. Expression levels of claudins were also regulated by copper in a concentration-dependent manner. We identified four claudin isoforms (1, 3, 5, and 12) and showed that their expression levels were regulated as a group by copper. Antioxidant activity of BMECs was also copper regulated, and superoxide dismutase and catalase were the main contributors to BMEC antioxidant functions. Together, our results indicated that copper had dual effects on BMEC growth and intrinsic antioxidant activities played a crucial role in BMEC survival and tight junction.

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Long-Term Supplementation with Chromium Malate Improves Short Chain Fatty Acid Content in Sprague-Dawley Rats

Abstract

Our previous study showed that chromium malate improved the composition of intestinal flora, glycometabolism, glycometabolism-related enzymes, and lipid metabolism in type 2 diabetes mellitus (T2DM) rats. The present study was designed to evaluate the effect of chromium malate with long-term supplementation on short chain fatty acid (SCFA) content in Sprague-Dawley rats. The samples were analyzed by gas chromatography with high linearity (R ² ≥ 0.9995), low quantification limit (0.011–0.070 mM), and satisfactory recoveries. The method was simple and environmentally friendly. The acetic content in cecum of 3-month control group was significantly higher than that of 1-year control group. When compared with 1-year control group, chromium malate (at a dose of 20.0 μg Cr/kg bw) could significantly increase acetic, propionic, i-butyric butyric, butyric, i-valeric, valeric, and n-caproic levels. The acetic, propionic, i-butyric, valeric, and n-caproic contents of 1-year chromium malate group (at a dose of 20.0 μg Cr/kg bw) had a significant improvement when compared with 1-year chromium picolinate group. Acetic, propionic, and butyric contained approximately 91.65 % of the total SCFAs in 1-year group. The results indicated that the improvement of chromium malate on short chain fatty acid content change was better than that of chromium picolinate.

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Protective Role of Zinc and Magnesium against Cadmium Nephrotoxicity in Male Wistar Rats

Abstract

Cd is a toxic metal that has a destructive impact on most organ systems. This work aims to determine Zn or Mg protective effects against Cd renal toxicity. In this study, rats were divided into six groups. The Cd group was treated with 1 mg Cd/kg, and the control group received 0.5 cm³ normal saline, intraperitoneally. The other four groups received one of the following dosages of 1 mg/kg Cd + 0.5 mg/kg Zn, 1 mg/kg Cd + 1.5 mg/kg Zn, 1 mg/kg Cd + 0.5 mg/kg Mg, or 1 mg/kg Cd + 1.5 mg/kg Mg through IP injection for 3 weeks. Kidney malondialdehyde (MDA) and serum sodium, potassium, urea, creatinine, and protein were measured. Light microscopic examination was used for histological studies. Cd reduced serum creatinine and protein, and increased urea, sodium, and potassium. Moreover, Cd exposure caused a significant enhancement in MDA levels as well as histological damage in kidneys. Zn or Mg treatment prevented and reversed toxic alterations induced by Cd. These results suggest that Zn and Mg may have protective effects against Cd renal toxicity.

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An Incredible Mentor: a Tribute to Dick Bakemeier

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Development of Plain Language Supplemental Materials for the Biobank Informed Consent Process

Abstract

The US Department of Health and Human Services addresses clear communication in the informed consent process as part of the Notice of Proposed Rulemaking for revisions to the Common Rule. However, prior research has shown that participants may not fully comprehend research studies despite completion of an informed consent process. Our main goal was to provide plain language information about donation processes to a cancer biobank to supplement an informed consent form. We developed and conducted cognitive testing with supplemental brochures that clearly communicated information about three different models for consent (notice, broad and study-specific) to future use of biospecimens. During the brochure development process, we conducted qualitative, semi-structured, individual, in-person cognitive interviews among 14 women to examine participants' perceptions of the brochures. Each participant provided feedback regarding the understandability, graphics and layout, and cultural appropriateness of the brochures. Our findings demonstrate that these methods may be used to tailor consent form brochures, such as the ones developed here, to other populations. This study therefore adds to our understanding of how best to present content to help women from two different racial groups make informed decisions about participation in a cancer biobank.

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