Efficient secretory expression of phospholipase D for the high-yield production of phosphatidylserine and phospholipid derivates from soybean lecithin.

Phospholipase D (PLD) is an essential biocatalyst for the biological production of phosphatidylserine and phospholipid modification. However, the efficient heterologous expression of PLD is limited by its cell toxicity. In this study, a PLD was secretory expressed efficiently in Bacillus subtilis with an activity around 100 U/mL. A secretory expression system containing the signal peptide SPEstA and the dual-promoter PHpaII-SrfA was established, and the extracellular PLD activity further reached 119.22 U/mL through scale-up fermentation, 191.30-fold higher than that of the control. Under optimum reaction conditions, a 61.61% conversion ratio and 21.07 g/L of phosphatidylserine production were achieved. Finally, the synthesis system of PL derivates was established, which could efficiently synthesis novel PL derivates. The results highlight that the secretory expression system constructed in this study provides a promising PLD producing strain in industrial application, and laid the foundation for the biosynthesis of phosphatidylserine and other PL derivates. As far as we know, this work reports the highest level of extracellular PLD expression to date and the enzymatic production of several PL derivates for the first time.

Endometrial clear cell carcinoma invading the right oviduct with a cooccurring ipsilateral oviduct adenomatoid tumor: A case report.

BACKGROUND: To investigate the clinicopathological features of endometrial clear cell carcinoma that has invaded the right oviduct with a cooccurring ipsilateral oviduct adenomatoid tumor. CASE SUMMARY: A case of endometrial clear cell carcinoma invading the right oviduct with a cooccurring ipsilateral oviduct adenomatoid tumor was collected and analyzed using pathomorphology and immunohistochemistry. Endometrial clear cell carcinoma cells were distributed in a solid nest, papillary, shoe nail-like, and glandular tube-like distribution. There was infiltrative growth, and tumor cells had clear cytoplasm and obvious nuclear heteromorphism. The cancer tissue was necrotic and mitotic. The cancer tissue invaded the right oviduct. The ipsilateral oviduct also had an adenomatoid tumor. The adenomatoid tumor was arranged in microcapsules lined with flat or cubic cells that were surrounded by smooth muscle tissue. The adenomatoid tumor cells were round in shape. CONCLUSION: Clear cell carcinoma of the endometrium can invade the oviduct and occur simultaneously with tubal adenomatoid tumors. Upon pathological diagnosis, one should pay close attention to distinguishing whether an endometrial clear cell carcinoma is invading the oviduct or whether it is accompanied by an adenomatoid tumor of the oviduct. Immunohistochemistry is helpful to differentiate these two disease entities. Endometrial clear cell carcinomas express Napsin-A and P16 and are negative for estrogen receptor and progesterone receptor. The presence of endometrial clear cell carcinoma does not affect the expression of CK and calretinin in adenomatoid tumors.

Association between Pax8-PPARandgamma;1 Rearrangement and Follicular Thyroid Cancer: a Meta-Analysis.

BACKGROUND: Pax8 and peroxisome proliferator-activated receptor gamma 1 gene (Pax8-PPARγ1) are important factors in tumors. Several studies have suggested that follicular thyroid cancer may arise from Pax8- PPArγ1 rearrangement. In order to have a better understanding of the association between Pax8-PPARγ1 rearrangement and follicular thyroid cancer, we conducted the presenmt meta-analysis. MATERIALS AND METHODS: The information was extracted from PubMed, EMBASE and Web of Science. Statistic analysis was performed with Stata12.0 software. Odds ratios (ORs) were calculated using a fixed-effects model. We also performed heterogeneity and publication bias analyses. RESULTS: Nine studies including 198 follicular thyroid cancer patients and 268 controls were considered eligible. The frequency of Pax8-PPARγ1 rearrangement was significantly higher in the follicular thyroid cancer group than in the control group, with a pooled OR of 6.63 (95%CI=3.50-12.7). In addition, through subgroup analysis, the OR between Pax8-PPARγ1 rearrangement and follicular thyroid cancer was 6.04 (95%CI = 3.18-11.5) when using benign tumor tissues as controls. The OR for the method subgroup was 9.99 (95% CI =4.86-20.5) in the RT-PCR. CONCLUSIONS: The final results demonstrated that Pax8-PPARγ1 rearrangement has significant association with follicular thyroid cancer.

[Effects of red tide microalgae Alexandrium tamarense on the life history of rotifer Brachionus plicatilis].

In this paper, life-table method was used to study the effects of different concentration Alexandrium tamarense on the durations of different development stages of Brachionus plicatilis and the characters of its population growth. The results showed that A. tamarense had significant effects on the growth and development of B. plicatilis via prolonging the durations of the rotifer' s pre-reproduction and generation succession, shortening the durations of its reproduction and post-reproduction and its mean lifespan, and reducing its laying eggs and fecundity. The net reproduction rate and intrinsic increasing rate of B. plicatilis decreased significantly, in comparison with those of the control. B. plicatilis could maintain definite population increase at the presence of different concentration A. tamarense.