University of Federal Maranhao

A combined experimental and computational investigation was conducted on the crystal L-phenylalanine L-phenylalaninium malonate (LPPMA) to explore its structural, electronic, vibrational, and thermal properties. X-ray diffraction analysis confirmed that LPPMA crystallizes in the monoclinic P2₁ space group, with zwitterionic and cationic phenylalanine molecules and malonate anions forming hydrogen-bonded layers and orthogonal hydrophobic stacking. Molecular and solid-state (periodic) DFT calculations were also performed. The LDA-D band structure revealed a quasi-degenerate fundamental electronic gap of 4.14 eV, with the highest occupied and lowest unoccupied crystal orbitals (HOCO and LUCO) localized on Phe and Phe⁺ units, respectively. Complementary hybrid functional calculations using HSE06 yielded an increased band gap of 5.48 eV, providing a more accurate upper-bound estimate in agreement with the material's insulating character. TD-DFT/B3LYP molecular calculations predicted a strong vertical excitation at 5.69 eV, in close agreement with the most intense experimental UV-vis absorption band at 5.99 eV. Temperature-dependent Raman spectroscopy (298-468 K) demonstrated redshifts and progressive intensity loss of vibrational modes, culminating in irreversible spectral suppression above 468 K. DFPT simulations supported vibrational assignments and elucidated the role of supramolecular interactions in stabilizing the crystal structure under thermal stress. Thermogravimetric and thermal analyses identified a five-step thermal degradation process, associated with the sequential release of NH₃, CO₂, and CH₂ fragments.

Post-kala-azar dermal leishmaniasis (PKDL) is a skin condition that can become a complication in about 15 % of patients who have had kala-azar. Despite its significance, treatment options for PKDL are still limited. This systematic review and meta-analysis aim to evaluate the efficacy of amphotericin B for this condition.

PubMed, Embase, Cochrane, and Web of Science databases were searched for randomized controlled trials (RCTs) that reported the efficacy of Liposomal Amphotericin B in the treatment of PKDL. This study followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Events per 100 observations with 95 % confidence intervals were performed for outcomes.

Nine studies with 639 patients were included, the treatment durations ranging from 7 to 60 days. The mean age ranged from 9.2 to 31.0 years, and 359 patients were male. The PKDL treatment with liposomal amphotericin B resulted in a cure rate of 91.36 % (95 % CI: 76.60-97.15). However, a relapse was observed in 11.42 % (95 % CI: 6.20-20.8) of patients. Adverse events were common, with hepatic enzyme elevation (ALT/AST) being the most frequent (61.75 %; 95 % CI: 21.81-90.33), followed by fever in 29.93 % of cases (95 % CI: 5.09-77.30). Among the more serious side effects, decreased serum potassium was observed in 19.27 % (95 % CI: 3.84-58.82), and increased serum creatinine, indicative of nephrotoxicity, occurred in 15.08 % (95 % CI: 3.97-43.27). Nausea or vomiting, although less severe, affected 12.36 % of patients (95 % CI: 4.81-28.25).

These findings highlight that while liposomal amphotericin B is a potent therapeutic option for PKDL, its administration requires careful management and clinical vigilance to optimize outcomes and minimize risks.

This study evaluated the influence of operational conditions on the efficiency of supercritical fluid extraction (SFE), a green technique, in comparison with conventional Soxhlet extraction, aiming to assess its efficiency based on global yield (X₀), chemical composition of the extracts (fatty acids profile, glyceride classes - MAG, DAG, and TAG, free fatty acids, and TAG composition), and the recovery of bioactive compounds such as coumarin, tocopherols, and tocotrienols from cumaru (Dipteryx odorata) seeds. The results demonstrated that SFE, operating under high CO₂ density (35 MPa; 40 °C), favored the extraction of lipophilic and antioxidant compounds, with recoveries expressed per gram of dried cumaru seeds (DCS). Under these conditions, the highest total tocol content (14.45 μg gDCS^-1), total reducing capacity (TRC) (552.17 μgGAE gDCS^-1) and Lipophilic Oxygen Radical Absorbance Capacity (ORAC-L) (1380.99 μgTE gDCS^-1) were observed, compared to the other evaluated conditions. Additionally, the extract obtained at this condition presented high lipid content (∼98%), high concentrations of oleic acid (∼52%) and linoleic acid (∼21%), besides a low acidity index, below the maximum limit recommended by the Codex Alimentarius. Soxhlet extraction resulted in a lower coumarin (0.82 μg gDCS^-1) and tocol content (3.29 μg gDCS^-1). The highest coumarin recovery was obtained at 25 MPa and 50 °C (10.11 mgCE gDCS^-1). SFE performed under the lowest CO₂ density (15 MPa; 60 °C) obtained the extract with the highest concentration of total tocols, TRC and ORAC-L; however, it yielded the lowest lipid recovery (11.57%). In summary, the findings highlight SFE as a promising approach for the selective and efficient extraction of high-value bioactive compounds from CS.