Study on the removal effect and mechanism of calcined pyrite powder on Cr(VI).

Pyrite exhibits considerable potential as an adsorbent in wastewater treatment. However, few pyrite adsorbents are directly obtained from natural pyrite, as most are composite materials that require a complex preparation process. To develop a pyrite-based adsorbent with a simple preparation process, pyrite was processed by calcination at 400, 600, and 800 °C for 4 h and ball-milled into a fine powder. The adsorption properties of the pyrite powder were systematically explored. The calcined pyrite powder was characterized by SEM-EDS and XRD. The results revealed that the pyrite calcined at 600 °C exhibited excellent adsorption properties and was primarily composed of Fe7S8. The optimum conditions for Cr(VI) removal were a temperature of 45 °C, an adsorbent dosage of 1 g, an equilibration time of 60 min, and an initial pH of 3. Moreover, the calcined pyrite powder exhibited excellent reusability, and the Cr(VI) removal rate exceeded 65% after three cycles. The Cr(VI) adsorption on pyrite can be well described by the Freundlich model and pseudo-second-order kinetic equation. The calcination temperature is the main factor affecting the adsorption performance of pyrite. Therefore, the calcined pyrite powder is expected to be an excellent adsorbent for Cr(VI) in the wastewater treatment industry.

Pyrite has shown promising development prospects in the field of wastewater purification. However, the preparation of most pyrite-based adsorbents is complicated. Upon high-temperature calcination, pyrite is used in traditional Chinese medicine clinics to promote the healing of fractures. The efficiency and underlying mechanism of Cr(VI) adsorption from water using calcined pyrite was investigated. The adsorbent was prepared using a simple method and exhibited excellent adsorption performance, thus allowing its application in preparing ore-based adsorbents for water pollution treatment.

A graphene oxide-loaded processed pyritum composite hydrogel for accelerated bone regeneration via mediation of M2 macrophage polarization.

A coordinated interaction between osteogenesis and the osteoimmune microenvironment plays a vital role in regulating bone healing. However, disturbances in the pro- and anti-inflammatory balance hinder the therapeutic advantages of biomaterials. In this study, a novel composite hydrogel was successfully fabricated using graphene oxide (GO)-loaded processed pyritum (PP) in combination with poly(ethylene glycol) diacrylate (PEGDA) and carboxymethyl chitosan (CMC). Subsequently, the immunomodulatory effects and bone regenerative potential of PP/GO@PEGDA/CMC were investigated. The results demonstrated that the PP/GO@PEGDA/CMC hydrogel possessed excellent mechanical properties, swelling capacity, and stability. Moreover, PP/GO@PEGDA/CMC prominently promoted M2 polarization and increased the levels of anti-inflammatory factors (interleukin (IL)-4, IL-10, and transforming growth factor-ß). These beneficial effects facilitated the proliferation and osteogenic differentiation of bone marrow mesenchymal stem cells in vitro. Additionally, the in vivo results further verified that the implantation of PP/GO@PEGDA/CMC markedly reduced local inflammation while enhancing bone regeneration at 8 weeks post-implantation. Therefore, the results of this study provide potential therapeutic strategies for bone tissue repair and regeneration by modulating the immune microenvironment.

Anti-arrhythmia potential of honey-processed licorice in zebrafish model: Antioxidant, histopathological and tissue distribution.

ETHNOPHARMACOLOGICAL RELEVANCE: Honey-processed licorice (HPL) is the roasted product of licorice. It is recorded in the "Shang Han Lun" that licorice has better protection on heart after honey-processed. However, researches regarding its protective effect on the heart and the distribution of HPL in vivo are still limited. AIM OF THE STUDY: To evaluate the cardio-protection of HPL and explore the law of ten main components distribution in vivo under physiological and pathological conditions for an attempt to clarify the pharmacological substance basis of HPL in treating arrhythmia. MATERIALS AND METHODS: The adult zebrafish arrhythmia model was established by doxorubicin (DOX). Electrocardiogram (ECG) was used to detect the heart rate changes of zebrafish. SOD and MDA assays were used to evaluate oxidative stress levels in the myocardium. HE staining was used to observe the morphological change of myocardial tissues after HPL treatment. The UPLC-MS/MS was adapted to detect the content of ten main components of HPL in heart, liver, intestine, and brain under normal and heart injury conditions. RESULTS: Heart rate of zebrafish was decreased, the SOD activity was attenuated and MDA content was increased in myocardium after administration of DOX. Moreover, tissue vacuolation and inflammatory infiltration were detected in zebrafish myocardium induced by DOX. HPL could ameliorate heart injury and bradycardia induced by DOX to a certain extent by increasing SOD activity and reducing MDA content. In addition, the study of tissue distribution revealed that the content of liquiritin, isoliquiritin, and isoliquiritigenin in the heart was higher in the presence of arrhythmias than those in the normal condition. Under pathological conditions, the heart highly exposed to these three components could elicit anti-arrhythmic effects by regulating immunity and oxidation. CONCLUSION: These findings indicate that the HPL is protective against heart injury induced by DOX, and its effect is associated with the alleviation of oxidative stress and tissue injury. And the cardioprotective effect of HPL under pathological conditions may be related to the high distribution of liquiritin, isoliquiritin, and isoliquiritigenin in heart tissue. This study provides an experimental basis for the cardioprotective effects and tissue distribution of HPL.

Lactobacillus rhamnosus GG ameliorates osteoporosis in ovariectomized rats by regulating the Th17/Treg balance and gut microbiota structure.

BACKGROUND: With increasing knowledge about the gut - bone axis, more studies for treatments based on the regulation of postmenopausal osteoporosis by gut microbes are being conducted. Based on our previous work, this study was conducted to further investigate the therapeutic effects of Lactobacillus rhamnosus GG (LGG) on ovariectomized (OVX) model rats and the immunological and microecological mechanisms involved. RESULTS: We found a protective effect of LGG treatment in OVX rats through changes in bone microarchitecture, bone biomechanics, and CTX-I, PINP, Ca, and RANKL expression levels. LGG was more advantageous in promoting osteogenesis, which may be responsible for the alleviation of osteoporosis. Th17 cells were imbalanced with Treg cells in mediastinal lymph nodes and bone marrow, with RORγt and FOXP3 expression following a similar trend. TNF-α and IL-17 expression in colon and bone marrow increased, while TGF-ß and IL-10 expression decreased; however, LGG treatment modulated these changes and improved the Th17/Treg balance significantly. Regarding the intestinal barrier, we found that LGG treatment ameliorated estrogen deficiency-induced inflammation and mucosal damage and increased the expression of GLP-2 R and tight junction proteins. Importantly, 16S rRNA sequencing showed a significant increase in the Firmicutes/Bacteroidetes ratio during estrogen deficiency. Dominant intestinal flora showed significant differences in composition; LGG treatment regulated the various genera that were imbalanced in OVX, along with modifying those that did not change significantly in other groups with respect to the intestinal barrier, inflammation development, and bile acid metabolism. CONCLUSIONS: Overall, LGG ameliorated estrogen deficiency-induced osteoporosis by regulating the gut microbiome and intestinal barrier and stimulating Th17/Treg balance in gut and bone.