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The dissolution of chalcopyrite under near ambient conditions represents one of the main challenges in the copper industry. Thus, various routes have been proposed for chalcopyrite treatment, such as the use of polar organic solvents, and this has shown promising results. In this paper, we present a study of copper leaching from a chalcopyrite concentrate in aqueous acidic medium with methanol and various H2O2 concentrations at 15, 30, and 40 °C. The results show that nearly complete copper extraction was attained within 5 h at 40 °C. The extraction percentages were plotted as functions of time at each temperature. The experimental data were modeled using the shrinking core model considering the cylindrical particle shape (shrinking cylinder model) within acceptable confidence levels, yielding an estimated activation energy of 24.3 kJ/mol. Furthermore, the process was dependent on the H2O2 concentration, and it acts as a reagent rather than an oxidant in the leaching reaction. It was found that sulfur is the only species present in the solid phase formed during the leaching of chalcopyrite, demonstrating the co-dissolution of both copper and iron. [ABSTRACT FROM AUTHOR]

The present study examines the possible inhibitory effect of JM-20, a multi-target neuroprotective compound, on the development of morphine-induced hyperalgesia in Male Sprague-Dawley naïve rats. Additionally, the impact of JM-20 on chronic constriction injury (CCI) rats under chronic morphine exposure was investigated, and its efficacy in reducing mechanical hypersensitivity and histopathological changes in the sciatic nerve was assessed. JM-20 (20 mg/kg, per os [p.o.]), administered 60 min before morphine (10 mg/kg, s.c. twice daily at 12 h intervals) for ten days, significantly inhibited the development of morphine-induced hyperalgesia assessed using an electronic pressure-meter paw test, hot-plate, and formalin test, as well as the appearance of spontaneous withdrawal somatic symptoms in rats. Furthermore, JM-20 decreases spinal pro-inflammatory interleukin-1β and restores glutathione to close physiological concentrations, biomarkers directly related to the intensity of mechanical hypernociception. After CCI and sham surgery, co-treatment with JM-20 (10 mg/kg, p.o.) for five days decreased morphine increased-mechanical hypersensitivity, even 12 days after its discontinuation. Continued morphine treatment imposed a neuroinflammatory challenge in CCI animals, further increasing cellularity (>75% immune cell infiltration) with lymphocytes and macrophages. However, JM-20 co-treatment still reduced the presence of cellular infiltrates (51-75%) with a predominance of lymphocytes. Even in the absence of nerve injury, JM-20 attenuated the peripheral neuroinflammatory response observed in morphine-treated sham-operated animals (0% vs. 1-25%). These findings suggest that JM-20 could prevent morphine-induced hyperalgesia by anti-inflammatory and antioxidant mechanisms., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Objective: Systemic lupus erythematosus (SLE) is a chronic multisystem autoimmune disorder where the disease activity itself and the medications used for its treatment, may have adverse effects on ovarian function. This study aimed to assess the ovarian reserve (OR) in SLE patients. Materials and methods: The anti-müllerian hormone (AMH) and the antral follicle count (AFC), two markers to evaluate the OR was assessed in 64 SLE patients and compared to normal individuals. Additionally, we assessed whether the disease per se or the pharmacological treatments affect the OR. Results: Patients with SLE displayed alterations in the OR regardless of the presence of alterations of the menstrual cycle. The AFC and AMH were significantly lower in SLE patients with and without menstrual alterations when compared to control individuals (p<0.0001). However, the AFC and AMH levels were significantly correlated (p=0.006) in the SLE patients with menstrual alterations. Except for hydroxychloroquine that was statistically higher in SLE patients with menstrual alterations (p=0.04), the cumulative dose for cyclophosphamide, corticosteroid, and methotrexate was similar in SLE patients regardless of the occurrence of menstrual alterations. Conclusion: The monitoring of AMH and AFC in SLE patients should be used to detect the rapid and irreversible decline of the OR to provide a possibility of pregnancy to the SLE patients., (Copyright © 2021 Tehran University of Medical Sciences. Published by Tehran University of Medical Sciences.)