RESUMEN
Glioma cancer is the primary cause of cancer-related fatalities globally for both men and women. Traditional chemotherapy treatments for this condition frequently result in reduced efficacy and significant adverse effects. This investigation developed a new drug delivery system for the chemotherapeutic drug temozolomide (TMZ) using pH-sensitive drug delivery zeolitic imidazolate frameworks (ZIF-8). These nanoplatforms demonstrate excellent biocompatibility and hold potential for cancer therapy. Utilizing the favorable reaction milieu offered by ZIFs, a 'one-pot method' was employed for the fabrication and loading of drugs, leading to a good capacity for loading. TMZ@TA@ZIF-8 NPs exhibit a notable response to an acidic milieu, resulting in an enhanced drug release pattern characterized by a controlled release outcome. The effectiveness of TMZ@TA@ZIF-8 NPs in inhibiting the migration and invasion of U251 glioma cancer cells, as well as promoting apoptosis, was confirmed through various tests, including MTT (3-(4,5)-dimethylthiahiazo(-z-y1)) assay, DAPI/PI dual staining, and cell scratch assay. The biochemical fluorescent staining assays showed that TMZ@TA@ZIF-8 NPs potentially improved ROS, reduced MMP, and triggered apoptosis in U251 cells. In U251 cells treated with NPs, the p53, Bax, Cyt-C, caspase-3, -8, and -9 expressions were significantly enhanced, while Bcl-2 expression was diminished. These outcomes show the potential of TMZ@TA@ZIF-8 NPs as a therapeutic agent with anti-glioma properties. Overall, the pH-responsive drug delivery systems we fabricated using TMZ@TA@ZIF-8 NPs show great potential for cancer treatment. This approach has the potential to make significant contributions to the improvement of cancer therapy by overcoming the problems associated with TMZ-based treatments.
RESUMEN
The simple ABO3 and A-site-ordered AA'3B4O12 perovskites represent two types of classical perovskite functional materials. There are well-known simple perovskites with ferroelectric properties, while there is still no report of ferroelectricity due to symmetry breaking transition in A-site-ordered quadruple perovskites. Here we report the high pressure synthesis of an A-site-ordered perovskite PbHg3Ti4O12, the only known quadruple perovskite that transforms from high-temperature centrosymmetric paraelectric phase to low-temperature non-centrosymmetric ferroelectric phase. The coordination chemistry of Hg2+ is changed from square planar as in typical A-site-ordered quadruple perovskite to a rare stereo type with 8 ligands in PbHg3Ti4O12. Thus PbHg3Ti4O12 appears to be a combinatory link from simple ABO3 perovskites to A-site-ordered AA'3Ti4O12 perovskites, sharing both displacive ferroelectricity with former and structure coordination with latter. This is the only example so far showing ferroelectricity due to symmetry breaking phase transition in AA'3B4O12-type A-site-ordered perovskites, and opens a direction to search for ferroelectric materials.
RESUMEN
OBJECTIVE: To explore the types of primary trigeminal neuralgia (TN) responsible vessels and curative efficacies of microscopic vascular decompression (MVD). METHODS: A total of 162 primary TN patients underwent MVD from August 2004 to the present at our hospital.Their clinical data were collected and analyzed. There were 69 males and 93 females with an age range of 22-88 years. RESULTS: The most common responsible vessels were superior cerebellar artery (n = 65, 40.12%), anteroinferior cerebellar artery (n = 45, 27.78%), multiple vessels (n = 26, 16.05%), posteroinferior cerebellar artery (n = 16, 9.88%), veins (n = 6, 3.70%) and vertebral artery (n = 4, 2.47%). And the pressure points were at the root of trigeminal nerve (n = 139, 85.80%), distal part (n = 16, 9.88%) and root and distal part (n = 7, 4.32%). Postoperatively pain disappeared in all patients (including one case on second surgery). Postoperative follow-ups were conducted for 132 cases.Two cases recurred over 8 years and the recurrence rate was 1.52%. CONCLUSION: MVD is preferred method for primary TN non-responsive to pharmacotherapy. Identification and treatment of responsible vessels remain a key. Venous and distal pressure points should be taken care.