RESUMEN
While ß-peptides have been paid attention due to their diverse secondary structures, their application to the design of low-molecular-weight gelators (LMWGs) is less explored. In this work, chiral cyclic ß-amino acid-based ß-peptides were developed as ambidextrous LMWGs, wherein multiple hydrogen bonds between the amide moieties led to high gelation ability. Their molecular assembly was elucidated using spectroscopies, microscopy, and X-ray analysis. Further, the supramolecular gel was used as a platform for the enantioselective extraction of (S)-naproxen from its racemate under optimized conditions. These findings have expanded the utility of ß-peptides and shown the potential of supramolecular gels as a distinct dynamic medium for enantiomer separation.
Asunto(s)
Aminas , Geles , Estereoisomerismo , Geles/química , Aminas/química , Péptidos/química , Enlace de Hidrógeno , Naproxeno/química , Naproxeno/aislamiento & purificaciónRESUMEN
This study reports the formation of low-molecular-weight gelators based on carboxylic acids derived from chiral cyclicß-amino acids. The effect of their stereochemistry on the gelation of organic solvents was investigated, and their assemblies with the intermolecular interactions in the xerogels were proposed via infrared spectroscopy, X-ray diffraction, scanning electron microscopy, and crystallographic details of the related model compounds. The effect of the alkyl chain length on the gelators was studied, and they were applied to the chiral recognition of amines. Only one diastereomeric salt with amines afforded gels, whereas the others resulted in precipitates. Chiral recognition was also achieved in the gel state, and the appearance of the as-prepared gel changed upon the addition of each amine enantiomer, thus enabling the visual detection of their chirality.
RESUMEN
We prospectively investigated the outcome of personalized second-line treatment based on epidermal growth factor receptor (EGFR) gene status in previously treated patients with advanced non-small cell lung cancer (NSCLC). EGFR gene status was evaluable by LH-mobility shift assay in registered patients. Gefitinib (Gef) treatment was recommended if the patients had EGFR mutation (mEGFR). EGFR gene status was evaluable in 146 patients. Seventy-four of the patients were female, 82 were smokers, and 122 had adenocarcinoma. Overall, 67 patients had mEGFR and received Gef. Forty-nine of 79 patients with wild-type EGFR (wEGFR) received other chemotherapies or radiation but 30 selected best supportive care only as a second-line treatment. Patients with mEGFR survived significantly longer than patients with wEGFR (p < 0.0001). However, the survival of patients who received other forms of chemotherapy was not different from that of patients who received best supportive care only as a second-line treatment in patients with wEGFR. Examination of the association between overall survival after first-line chemotherapy and prognostic factors using multivariate regression analysis showed that mEGFR and response to first-line chemotherapy were independent factors (p = 0.003 and p = 0.003, respectively). Selection of second-line treatment according to EGFR gene status may be useful for patients with NSCLC.
Asunto(s)
Antineoplásicos/uso terapéutico , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Receptores ErbB/genética , Neoplasias Pulmonares/tratamiento farmacológico , Mutación , Quinazolinas/uso terapéutico , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma de Pulmón de Células no Pequeñas/genética , Carcinoma de Pulmón de Células no Pequeñas/mortalidad , Receptores ErbB/antagonistas & inhibidores , Femenino , Gefitinib , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/mortalidad , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Tasa de SupervivenciaRESUMEN
We observed the mature granulocytes/monocytes derived from leukemic cells in patients with acute myeloid leukemia who present mixed lineage leukemia gene (MLL). Morphologic observation and fluorescence in situ hybridization analysis (FISH) for chromosome 11q23 abnormality were studied, and a multiplex reverse transcriptase-polymerase chain reaction (RT-PCR) analysis was done to identify the fusion partners with MLL. The bone marrow cells with FISH signals of MLL showed the cell differentiation of the myeloid and/or monocytic lineages in 4 of 6 AML patients. MLL partner genes were AF6, AF9, ELL, and ENL, respectively. There was no correlation between the fusion partner and the appearance of mature cells derived from MLL clones. RT-PCR showed the fusion between MLL exon 9 or 10 and the partner genes in mature granulocytes/monocytes. These findings suggest that subgroup of leukemia cells with MLL rearrangement has the differentiation potential of leukemic cells and mature granulocytes/monocytes derived from MLL clones may be biologically different from normal mature cells.