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The generation of aldehydes and sulfoxides through selective oxidation process plays an essential role in different organic synthesis. However, using or toxic solvents under harsh reaction conditions leads to wastes and undesired by-products. With this background, ultrafast one-step fabrication of Ni/Mn doped-ZnO was developed under ultrasonic agitation for the first time. The resulting nanostructure was characterized by XRD, SEM, TEM, and BET analysis. According to data, a single-phase ZnO structure (wurtzite type) with uniform morphology, and acceptable surface area was obtained for the prepared nanocatalyst. Next, the catalytic activity of the nanostructure was investigated in aerobic oxidation of aliphatic and benzylic alcohols and sulfides. Notably, the present work is the first report of using ultrasound-engendered Ni/Mn doped-ZnO for selective aerobic oxidation reactions. It was found that the proposed nanostructure represented a novel chemical function for catalyzed alcohols and sulfides oxidation with excellent yields and selectivity without using any additives. [ABSTRACT FROM AUTHOR]

The traditional form of carbon nitride materials poses limitations, particularly in catalysis, due to a limited number of active sites and low surface area. In response to these challenges, two porous carbon nitride tubes (CNTs) with diverse properties were designed and fabricated by introducing different poly-(ionic liquid)-s (PILs) as templates. Imidazolium-based PILs were synthesized with different ion pairs, including halogen (Br) and chiral amino acid (l-phenylalanine). The results indicate that the morphology and properties of CNTs are influenced by the nature of PIL ion pairs. Synthesized CNT, assisted by PIL-Br (designated as CNT1), demonstrated superior characteristics in terms of thermal stability (up to 640 °C), specific surface area (73.5 m2/g), and recoverability (six runs without a significant decrease in reaction yield), which are the key factors of a high-performance catalyst. In the following, CNT architectures were employed as heterogeneous catalysts, and their catalytic efficiencies were compared in the regiospecific synthesis of benzimidazole ring systems. As expected, CNT1 demonstrates superfast synthesis (8–12 min) of various pharmaceutical benzimidazole scaffolds with excellent yields (up to 95%) under ultrasound irradiation. In a groundbreaking achievement, this is the first report that presents the preparation of a superactive catalyst through the integration of two distinct categories of advanced materials, including ionic polymers and graphite carbon nitrides, for regiospecific multicomponent reactions. This study offers a fresh perspective on enhancing the catalytic activity of graphitic carbon nitride by changing ion pairs of PILs for advanced technological applications. [ABSTRACT FROM AUTHOR]

Superabsorbent polymers (SAPs) were synthesized by aqueous solution polymerization of carboxymethyl cellulose (CMC)/acrylic acid (AAc) and polyvinyl alcohol (PVA)/AAc blend using benzoyl peroxide as an initiator. SAPs were synthesized by a facile method under mild conditions. A comparative study was done between CMC/AAc as a biodegradable superabsorbent and PVA/AAc copolymer. The effects of cross-linking, reaction time, temperature, and initiator molar ratio on water absorbency were studied herein. The highest swelling capacity was obtained for CMC/AAc biodegradable superabsorbent composite. The water absorption capacity of SAPs increased with increases in benzoyl peroxide content, immersion time, and reaction temperature of polymerization. The gel fraction of SAPs decreased with increases in the amounts of N, N ′-methylenebisacrylamide as a cross-linker. Fourier-transform infrared spectroscopy was used to examine the molecular interactions. The morphology and structure of superabsorbent composites were investigated by scanning electron microscopy. [ABSTRACT FROM AUTHOR]

Background: Paraquat (PQ) is an herbicide that is genotoxic and cytotoxic for male germ cells. In this study, we investigated the protective role of crocin (Cr) against the destructive effects of PQ on sperm quality and in vitro fertilization (IVF) outcomes. Materials and Methods: In this experimental study, a total of 28 male mice (20-25 g) were divided into four groups: control, which received intraperitoneal (IP) injections of 0.1 ml normal saline per day; PQ group received IP injections of PQ (5 mg/kg/day); experimental (PQ+Cr group) received PQ along with IP injections of Cr (200 mg/kg/day); and positive control (Cr) received IP injections of Cr (200 mg/kg/day). In the last two weeks of the treatment period (35 days of treatment), 16 non-pregnant mice were stimulated to receive adult oocytes. At the end of the treatment period, after euthanizing the mice, the sperms were extracted from the epididymis of each mouse and prepared for evaluation of sperm parameters and IVF. Results: In the PQ+Cr group, Cr caused a significant increase in the average number of sperms and the mean percentage of motile and viable sperms. There was a significant decrease in the mean number of immature and DNA-damaged sperms compared to the PQ group (P<0.001). IVF evaluation in the PQ+Cr group showed that the mean percentage of fertilization, two- and four-cell embryos, blastocysts, and hatched embryos significantly increased. Cr caused a significant decrease in the mean percentage of the arrested embryos compared to the PQ group (P<0.001). However, the Cr group did not have any toxic effects on sperm quality or IVF results. Conclusion: The findings of this study showed that Cr, due to its effective and potent antioxidant properties, could reduce or suppress the destructive effects on sperm parameters and IVF caused by PQ. [ABSTRACT FROM AUTHOR]

[Cd(C7H3NO4)(H2O)1.5]n or [Cd(2,6-pydc)(H2O)1.5]n, (1) (2,6-pydc = pyridine-2,6-dicarboxylate) was obtained from the I reaction of pyridine-2,6-dicarboxylic acid and 4-hydroxypyridine-2,6-dicarboxylic acid with cadmium(II) nitrate tetrahydrate in the presence of piperazine and characterized by elemental analysis, IR spectra and X-ray single crystal diffraction. Complex (1) is a novel carboxylate-bridged one-dimensional pincer-shaped helical chain of cadmium(II) polymer. Each Cd atom is seven-coordinate and exhibits an approximately pentagonal-bipyramidal CdNO6 coordination geometry. The metal fragments are linked via the central four-membered Cd2O2 ring and the structural analysis showed that 4-hydroxypyridine-2,6-dicarboxylic acid and piperazine do not appear in the structure. [ABSTRACT FROM AUTHOR]

As a common metabolic disorder, hyperglycemia (HG) affects and disrupts the physiology of various systems in the body. Transplantation of mesenchymal stem cells (MSCs) has been used to control the complications of disease. Most of the therapeutic properties of MSCs are attributed to their secretome. This study aimed to investigate the effects of conditioned media extracted from sole or caffeine pre-treated bone-marrow-derived MSCs on hyperglycemia-induced detrimental impact on some aspects of reproduction. The HG was induced by intraperitoneally injection of streptozotocin (65 mg/kg) and nicotinamide (110 mg/kg). Twenty-four male Wistar rats (190 ± 20 g) were divided into control, HG, and the hyperglycemic groups receiving conditioned media of proliferated MSCs solely (CM) or MSCs pre-treated with caffeine (CCM). During the 49-day treatment, body weight and blood glucose were measured weekly. Finally, HbA1c, spermatogenesis development, sperm count, morphology, viability, motility, chromatin condensation, and DNA integrity were examined. Also, testicular total antioxidant capacity (TAC), malondialdehyde, sperm fertilization potential, and pre-implantation embryo development were evaluated. A one-way ANOVA and Tukey's post-hoc tests were used to analyze the quantitative data. The p < 0.05 was considered statistically significant. The CM and with a higher efficiency, the CCM remarkably (p < 0.05) improved body weight and HG-suppressed spermatogenesis, enhanced sperm parameters, chromatin condensation, DNA integrity, and TAC, reduced HbA1c, sperm abnormalities, and malondialdehyde, and significantly improved pre-implantation embryo development versus HG group. The conditioned media of MSCs solely (CM) and more effectively after pre-treatment of MSCs with caffeine (CCM) could improve spermatogenesis development, sperm quality, pre-implantation embryo development, and testicular global antioxidant potential during hyperglycemia. [Display omitted] • Bone marrow-mesenchymal cells' conditioned media (CM and CCM) are useful in hyperglycemia. • Caffeine pretreatment improves the effects of bone marrow-mesenchymal cells' CM. • The CM and CCM improve the promoting spermatogenesis development in hyperglycemia. • The testicular antioxidant capacity is adjusted by CM and CCM in hyperglycemia. • The CM and CCM improve the sperm characteristics and fertilization in hyperglycemia. • The CM and CCM could enhance pre-implantation embryo development in HG condition. [ABSTRACT FROM AUTHOR]

Leptin, the 16-kDa product of the obese (ob) gene, primarily secreted from adipose tissue, has been implicated to play an important role in the regulation of food intake and energy expenditure. This study investigated protective effect of leptin on trichostatin A-induced apoptotic on in vitro maturation ratio of buffalo oocytes. Ovaries were collected from abattoir and were transported immediately to the laboratory by a thermos flask containing sterile normal saline with antibiotics. Oocytes were aspirated from 2 to 8 mm visible follicles. Oocytes were placed in a culture plate and then incubated at 38.5 ˚C with 5% CO2 in air for 24 hr. The maturation of oocytes was evaluated under a stereomicroscope. The FITC-Annexin V and propidium iodide staining method was used to detect oocyte apoptosis. In leptin treated groups with 0, 10, 50 and 100 ng mL(-1) and groups that apoptosis was induced, the percentage of oocytes maturation was 77.03, 86.12, 85.08, and 79.89% and 59.96, 56.93 and 51.98, respectively, while the percentage of apoptosis was 8.83, 7.90, 8.58, and 9.39%, and 10.37, 11.57 and 12.03, respectively. Our findings showed that addition of 10 and 50 ng mL(-1) leptin to IVM medium of buffalo oocytes could increase oocyte nuclear maturation, and could decrease oocyte apoptosis when trichostatin A added for inducing apoptosis.