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At present, the utilization of grease has attracted more and more attention. This article presents a simple method that efficiently cleaves methyl oleate‐derived methyl 9,10‐epoxystearate (a) to give high yields of methyl 9‐oxononanoate (d) with nonanal (c) as co‐product. A WO3/MCM‐41 catalyst is prepared via direct mixed‐gel synthesis. The catalyst is tested in the oxidative cleavage of a to produce d which can be used as a polymer precursor or an important feedstock. The effects of WO3 loading, temperature, time, H2O2/a molar ratio, catalyst/a weight ratio, and t‐BuOH/a weight ratio on the a conversion and d yield are examined using single‐factor experiments. The optimal reaction conditions are determined by orthogonal experiments. The optimal WO3 loading, temperature, time, H2O2/a molar ratio, catalyst/a weight ratio, and t‐BuOH/a weight ratio are 35%, 80 °C, 20 min, 1.3, 0.04, and 0.5, respectively. Under these conditions, the a conversion and d yield reach 99.4 and 78.4%, respectively. In addition, the catalyst shows no significant decrease in activity after being reused three times. Moreover, the reaction mechanism is studied based on the product distribution over time. Practical Applications: Few studies on methyl 9,10‐epoxystearate used as the raw material to give methyl 9‐oxononanoate and nonanal are found. Because the ethylene oxide bond is more unstable than the carbon–carbon double bond, the oxidative cleavage of methyl 9,10‐epoxystearate is easier than cleavage of methyl oleate that allows the oxidative cleavage to be done under milder conditions. Methyl 9‐oxononanoate can be converted to a monomer of high‐value polymers and is also an important feedstock in the production of chemicals. The co‐product nonanal is a natural spice which can be used in the fragrance industry. The results show that the reaction time is short and methyl 9‐oxononanoate yield is high under mild reaction conditions. The method in this study can also be widely used in other oxidative cleavage reactions of epoxides. Methyl 9,10‐epoxystearate is used as the raw material to produce methyl 9‐oxononanoate with nonanal as co‐product using WO3/MCM‐41 as catalyst and H2O2 as oxidant. [ABSTRACT FROM AUTHOR]

Eph receptors play important roles in the development of cancer. The present study aimed to investigate the expression of EphA1 and its clinicopathologic significance in esophageal squamous cell carcinoma ( ESCC). The expression levels of the EphA1 transcript and protein were compared between ESCC and matched normal mucosa in the same patient. High expression levels of the EphA1 transcript and protein were detected in 25.6% (21/82) and 23.2% (19/82) of tumors compared with matched normal mucosa. The up-regulation of EphA1 transcript in tumors was positively associated with differentiation (p = 0.002), disease stage (p = 0.034), and lymph node metastasis (p = 0.042). Increased expression of EphA1 protein in tumors was more often observed in patients with well-differentiated tumors (p = 0.004), lymph node metastasis (p = 0.028), and advanced tumor stage (p = 0.008). EphA1 protein expression was detected in intraepithelial neoplasias as well. Decreased expression of EphA1 protein was detected in 65.2% (15/23) of samples with low-grade neoplasia and in 85.3% (8/15) of samples with high-grade intraepithelial neoplasia. Increased staining of EphA1 protein was not detected in low-grade intraepithelial neoplasia samples, but was detected in 21.3% (2/15) of high-grade intraepithelial neoplasia samples. Taken together, our results show that EphA1 appears to be a differentiation marker for esophageal squamous cells, and its increased expression is positively associated with lymph node metastasis and advanced disease stage. [ABSTRACT FROM AUTHOR]