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Treatment of methyl mesopyropheophorbide a with formaldehyde under basic conditions gave a novel 13(2)-methylene derivative in 85% yield; under acidic conditions, the corresponding 20-hydroxymethyl derivative was obtained in 65% yield. The high reactivity of the enone structural motif existed in the former product provides a unique way to construct some novel chlorophyll a derivatives for various applications. Stereoselective Michael reaction of this compound is studied and discussed.
Assuntos
Formaldeído/química , Porfirinas/síntese química , Conformação Molecular , Porfirinas/química , EstereoisomerismoRESUMO
Novel starch/fiber composites with open cell structures were proposed through thermo-cavity molding. To overcome the disadvantage of the water sensitivity of the resulting composites, poly-methyltriethoxysilane (PTS) was added as a waterproofing agent. The results showed that the addition of PTS improved the waterproof property of the composites. The composites with 15 g PTS (PTS-15) exhibited an optimal waterproof property. The water contact angle and drop absorption of the PTS-15 composites improved by 59.9% and 223.5%, respectively, compared with the values for those without PTS. Moreover, the addition of PTS could effectively prevent the degradation of the mechanical properties of the composites after water absorption. The rate of tensile property degradation for the PTS-15 composites reached 5.3%, whereas that for the PTS-0 composites totaled 56.6%. The chemical bonds and micro-structure of the composites were investigated to reveal the inherent mechanism of property changes. Fourier transform infrared spectra revealed the formation of new hydrogen bonds between starch and PTS. Hydrophobic groups, including Si-O-Si, Si-C, and Si-OH, were found in the resulting composites, thereby explaining the waterproof property changes. Scanning electron microscopy images showed that the open cell structure of the composites initially became denser and then loosened with the increase in the PTS content, resulting in the initial enhancement and the subsequent weakening of their mechanical properties.
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INTRODUCTION: The fascin-1 protein is a cytoskeleton-like protein, which can prompt structural changes in cell membranes and affect the integrity of intercellular relations to promote invasion and metastasis of tumor cells. In this study, we researched the expression of fascin-1 in glioma. MATERIAL AND METHODS: The fascin-1 protein and mRNA were detected by immunohistochemistry and reverse transcription polymerase chain reaction (RT-PCR). Then, we analyzed the relationship between the expression of fascin-1 protein and the clinical pathological characteristics of patients with glioma. Finally, the fascin-1 protein expression status and prognosis of glioma patients were investigated. RESULTS: The fascin-1 protein was mainly located in the cytoplasm of cells from glioma. The high expression rate of fascin-1 protein in glioma tissue was higher than that of normal brain tissue. At same time, we found that high fascin-1 protein expression was significantly correlated with World Health Organization (WHO) grading of glioma patients. The results survival analysis suggested high expression of fascin-1 protein in glioma patients with a shorter survival time. Multivariate analysis showed that high expression of fascin-1 protein was an independent predictor of the prognosis of patients with glioma. CONCLUSIONS: High expression of the fascin-1 protein indicates poor prognosis for glioma patients.