Determining the Photoelectrical Behavior and Photocatalytic Activity of an h-YMnO3 New Type of Obelisk-like Perovskite in the Degradation of Malachite Green Dye.

YMnO3 is a P-type semiconductor with a perovskite-type structure (ABO3). It presents two crystalline systems: rhombohedral and hexagonal, the latter being the most stable and studied. In the hexagonal system, Mn3+ ions are coordinated by five oxygen ions forming a trigonal bipyramid, and the Y3+ ions are coordinated by five oxygen ions. This arrangement favors its ferroelectric and ferromagnetic properties, which have been widely studied since 1963. However, applications based on their optical properties have yet to be explored. This work evaluates the photoelectric response and the photocatalytic activity of yttrium manganite in visible spectrum wavelengths. To conduct this, a rod-obelisk-shaped yttrium manganite with a reduced indirect bandgap value of 1.43 eV in its hexagonal phase was synthesized through the precipitation method. The synthesized yttrium manganite was elucidated by solid-state techniques, such as DRX, XPS, and UV-vis. It was non-toxic as shown by the 100% leukocyte viability of mice BALB/c.

Nanohybrid of Thymol and 2D Simonkolleite Enhances Inhibition of Bacterial Growth, Biofilm Formation, and Free Radicals.

Due to the current concerns against opportunistic pathogens and the challenge of antimicrobial resistance worldwide, alternatives to control pathogen growth are required. In this sense, this work offers a new nanohybrid composed of zinc-layered hydroxide salt (Simonkolleite) and thymol for preventing bacterial growth. Materials were characterized with XRD diffraction, FTIR and UV-Vis spectra, SEM microscopy, and dynamic light scattering. It was confirmed that the Simonkolleite structure was obtained, and thymol was adsorbed on the hydroxide in a web-like manner, with a concentration of 0.863 mg thymol/mg of ZnLHS. Absorption kinetics was described with non-linear models, and a pseudo-second-order equation was the best fit. The antibacterial test was conducted against Escherichia coli O157:H7 and Staphylococcus aureus strains, producing inhibition halos of 21 and 24 mm, respectively, with a 10 mg/mL solution of thymol-ZnLHS. Moreover, biofilm formation of Pseudomonas aeruginosa inhibition was tested, with over 90% inhibition. Nanohybrids exhibited antioxidant activity with ABTS and DPPH evaluations, confirming the presence of the biomolecule in the inorganic matrix. These results can be used to develop a thymol protection vehicle for applications in food, pharmaceutics, odontology, or biomedical industries.

Human lactoferrin from breast milk: characterization by HPLC and its in vitro antibiofilm performance.

Preterm infants are at high risk of infection due to opportunistic bacteria as Pseudomonas aeruginosa, causing infections among infants in neonatal intensive care units. Human lactoferrin (hLf) is a multifunctional protein and one of the most abundant in breast milk, and plays an important role in prevention of different infections in neonates. This work offers a strategy to obtain a lyophilisate of purified lactoferrin from breast milk. In addition, a reliable HPLC method for quantification of lactoferrin with a linear quantification range of 0.040-0.140 mg/mL with selectivity, accuracy and repeatability, is described. Lyophilized hLf was obtained by purification through a heparin affinity column followed by ultrafiltration with a 30 kDa membrane. The final solution was lyophilized and the product was analyzed using HPLC method, recovering about 70% of initial lactoferrin in the sample. This molecule was elucidated through FTIR spectroscopy and SDS-PAGE electrophoresis. In addition, the capacity against biofilm formation of P. aeruginosa was demonstrated with 75% of inhibition at 6 mg/mL. These results suggest that lyophilized hLf can be obtained by purification of breast milk and that it can provide antibiofilm activity against P. aeruginosa.

Expression of ornithine decarboxylase in peripheral blood mononuclear cells from patients with pancreatic adenocarcinoma: A preliminary report.

Ductal adenocarcinoma represents 90-95% of pancreatic cancer (PC) cases and it is an aggressive disease with asymptomatic evolution at early stages, non-specific symptoms and a typical late diagnosis with a 5-year survival rate estimated to be 8%. A window of opportunity lies in early diagnosis as there are currently no reliable biomarkers. CA 19-9 is one of the most frequently used biomarkers of PC, with 75 and 77.6% sensitivity (Se) and specificity (Sp), respectively, and the carcinoembryonic antigen (CEA) shows 39.5 and 81.3% of Se and Sp, respectively. A case-control study was conducted including adult patients with a histological diagnosis of PC (n=11) without previous treatment at the Oncology Service of the CMNO-IMSS between 2019 and 2020, and a control group of adult volunteers (n=11) who were clinically healthy or with controlled disease including hypertension, hypothyroidism and diabetes. Clinical, laboratory and sociodemographic data as well as blood, urine and saliva samples were collected following patient consent. Polyamines were quantified using high-performance liquid chromatography with fluorescence detection, CA 19-9 and CEA were evaluated using enzyme-linked immunosorbent assay, and the protein expression of ornithine decarboxylase (ODC) was evaluated using western blotting. Polyamine metabolism and modulation by means of ODC were increased in the serum and saliva of patients with PC, and the expression of ODC alone was increased in peripheral blood mononuclear cells (PBMCs). The present study focused on the evaluation of putrescine, spermine, spermidine and ODC in PBMCs associated with CA 19-9 and CEA as an auxiliary tool in PC diagnosis.

Encapsulation of curcumin into layered double hydroxides improve their anticancer and antiparasitic activity.

OBJECTIVES: Curcumin (CUR) has well-known activity against cancer cells and parasites; however, its applications are limited since this is an unstable molecule, which may suffer degradation by light and temperature, also, the low water solubility reduce its bioavailability. Layered double hydroxides (LDH) are well-known materials owing to the excellent anion exchange capacity, good biocompatibility and low toxicity. METHODS: Layered double hydroxides nanoparticles prepared with zinc and magnesium cations were used as a vehicle for CUR in Caco-2, Giardia lamblia and Entamoeba histolytica cultures. The physicochemical properties of Mg-LDH-CUR and Zn-LDH-CUR were characterized by scanning electron microscopy (SEM), Fourier transform infrared spectrometry (FTIR) and X-ray powder diffraction (XRD). Additionally, the load efficiency, release profiles and photostability of CUR were quantified by high-performance liquid chromatography (HPLC) and UV-Vis spectrometry. Then, Mg-LDH-CUR and Zn-LDH-CUR were tested on Caco-2, G. lamblia and E. histolytica cultures. KEY FINDINGS: The experiments demonstrated that Zn-LDH-CUR protects better against photodegradation by UV light, while Mg-LDH-CUR showed increased toxicity against Caco-2 cell, G. lamblia and E. histolytica, in comparison with free CUR. CONCLUSIONS: Layered double hydroxides are good vehicles to improve stability, resistance to degradation of CUR, also they are useful to improve solubility, provide a controlled release and improve the cytotoxic activity. Additionally, it was shown that the composition of the M+2 cation of LDH affects its properties and structure and that this directly influences its biological activity. The findings are important to select the composition of the encapsulation vehicle for a specific activity.