Stepwise changes in flavonoids in spores/pollen contributed to terrestrial adaptation of plants.

Protecting haploid pollen and spores against UV-B light and high temperature, 2 major stresses inherent to the terrestrial environment, is critical for plant reproduction and dispersal. Here, we show flavonoids play an indispensable role in this process. First, we identified the flavanone naringenin, which serves to defend against UV-B damage, in the sporopollenin wall of all vascular plants tested. Second, we found that flavonols are present in the spore/pollen protoplasm of all euphyllophyte plants tested and that these flavonols scavenge reactive oxygen species to protect against environmental stresses, particularly heat. Genetic and biochemical analyses showed that these flavonoids are sequentially synthesized in both the tapetum and microspores during pollen ontogeny in Arabidopsis (Arabidopsis thaliana). We show that stepwise increases in the complexity of flavonoids in spores/pollen during plant evolution mirror their progressive adaptation to terrestrial environments. The close relationship between flavonoid complexity and phylogeny and its strong association with pollen survival phenotypes suggest that flavonoids played a central role in the progression of plants from aquatic environments into progressively dry land habitats.

Structurally Diverse Diterpenes from the South China Sea Soft Coral Sarcophyton trocheliophorum.

The present investigation of the South China Sea soft coral Sarcophyton trocheliophorum resulted in the discovery of six new polyoxygenated diterpenes, namely sartrocheliols A-E (1, 3, 5-8) along with four known ones, 2, 4, 9, and 10. Based on extensive spectroscopic data analysis, sartrocheliol A (1) was identified as an uncommon capnosane diterpene, while sartrocheliols B-E (3, 5-8) were established as cembrane diterpenes. They displayed diverse structural features not only at the distinctly different carbon frameworks but also at the various types of heterocycles, including the epoxide, γ-lactone, furan, and pyran rings. Moreover, their absolute configurations were determined by a combination of quantum mechanical-nuclear magnetic resonance (QM-NMR) approach, modified Mosher's method, and X-ray diffraction analysis. In the anti-tumor bioassay, compound 4 exhibited moderate cytotoxic activities against A549, H1975, MDA-MB-231, and H1299 cells with the IC50 values ranging from 26.3 to 47.9 µM.

Antitumor Cembrane Diterpenoids from the South China Sea Soft Coral Lobophytum sp.

Two new highly functionalized cembrane diterpenoids named ximaolobophytolides A (1) and B (2) as minor components, together with seven related known compounds (3-9), have been isolated and identified from the Ximao soft coral Lobophytum sp. They were characterized by the presence of an α-methylene-γ-lactone moiety. Based on the comprehensive analyses of 1D and 2D NMR spectroscopic data, the absolute configurations of these two new compounds were elucidated by the combination of quantum mechanical (QM)-NMR and time-dependent density functional theory/electronic circular dichroism (TDDFT-ECD) calculation approaches. In the anti-tumor bioassays, compounds 3-9 showed moderate to significant inhibitory effects (IC50 values ranging from 29.66 to 0.39 µM) against the proliferations of five tumor cells HEL, A549, H1975, MDA-MB-231, and H1299. It might be worthy to point out that compounds 4, 7, and 8 exhibited better anti-tumor activities than that of the positive control Doxorubicin.

Straightforward synthesis, characterization, and cytotoxicity evaluation of hybrids of natural alkaloid evodiamine/rutaecarpine and thieno[2,3-d]pyrimidinones.

Dozens of hybrids of natural alkaloid evodiamine/rutaecarpine and thieno[2,3-d]pyrimidinones were synthesized in a straightforward method by condensation of substituted 2H-thieno[2,3-d][1, 3]oxazine-2,4(1H)-diones or N-methyl-2H-thieno[2,3-d][1, 3]oxazine-2,4(1H)-dione with 3,4-dihydro-ß-carbolines. In vitro cytotoxic assay discovered that compounds 9a, 10e, 11a, 11d, 11f, and 12a could induce antiproliferation against four different types of human cancer cells while compounds 10f and 12e were inactive. Notably, compound 11a displayed potent cell cytotoxicity for human non-small cell lung cancer cells A549, PC-9, human prostate cancer cells PC-3, and human breast cancer cell line MCF-7. Furthermore, compound 11a exhibited strong colony formation inhibition to A549 cells. These results unfold potential anticancer therapeutic applications of hybrids of thieno[2,3-d]pyrimidinones and quinazolinones.

8-bromo-7-methoxychrysin suppress stemness of SMMC-7721 cells induced by co-culture of liver cancer stem-like cells with hepatic stellate cells.

BACKGROUND: Our previous works have demonstrated that 8-bromo-7-methoxychrysin suppressed stemness of human hepatocellular carcinoma (HCC) cell line SMMC-7721 induced by condition medium from hepatic stellate cell line LX-2 that was activated by liver cancer stem-like cells (LCSCs). However, whether and whereby BrMC inhibits the stemness induced by co-culture of LCSCs and LX-2 cells remains to be investigated. METHODS: The second-generation spheres by sphere culture were identified and used as SMMC-7721-and MHCC97H-derived LCSLCs. SMMC-7721-and MHCC97-derived LCSCs/LX-2 cells transwell co-culture system was treated with BrMC and its lead compound chrysin. The concentrations of IL-6, IL-8, HGF and PDGF in condition medium from co-culture were measured by enzyme-linked immunosorbent assay (ELISA). The stemness of SMMC-7721 cells was evaluated by sphere formation assay and western blot analysis for expression levels of cancer stem cell markers (CD133 and CD44).The expression levels of cancer-associated fibroblast markers (FAP-α and α-SMA) were employed to evaluate pathologic activation of LX-2 cells. Addition of IL-6 and/or HGF or deletion of IL-6 and/or HGF was conducted to investigate the mechanisms for BrMC and chrysin treatment in SMMC-7721-derived LCSLCs co-cultured with LX-2cells. RESULTS: The co-culture of LCSLCs with LX-2 cells increased sphere formation capability as well as expression of CD133 and CD44 in SMMC-7721 cells, meanwhile, upregulated expression of FAP-α in LX-2 cells. ELISA indicated that the concentrations of IL-6 and HGF were significantly elevated in Co-CM than that of condition media from co-cultured SMMC-7721 cells/LX-2 cells. Treatment of BrMC and chrysin with co-cultures of SMMC-7721- and MHCC97H-derived LCSLCs and LX-2 cells effectively inhibited the above responses. Moreover, addition of IL-6 and/or HGF induced stemness of SMMC-7721 cells and activation of LX-2 cells, conversely, deletion of IL-6 and/or HGF suppressed those. Furthermore, the inhibitory effects of BrMC and chrysin on stemness of SMMC-7721 cells and activation of LX-2 cells were attenuated by addition of IL-6 or HGF, and enhanced by deletion of IL-6 or HGF. CONCLUSIONS: Our results suggest IL-6 and HGF may be the key communication molecules for the interaction between LCSLCs and HSCs, and BrMC and chrysin could block these effects and be the novel therapeutic candidates for HCC management.

Cytological and Proteomic Analyses of Osmunda cinnamomea Germinating Spores Reveal Characteristics of Fern Spore Germination and Rhizoid Tip Growth.

Fern spore is a good single-cell model for studying the sophisticated molecular networks in asymmetric cell division, differentiation, and polar growth. Osmunda cinnamomea L. var. asiatica is one of the oldest fern species with typical separate-growing trophophyll and sporophyll. The chlorophyllous spores generated from sporophyll can germinate without dormancy. In this study, the spore ultrastructure, antioxidant enzyme activities, as well as protein and gene expression patterns were analyzed in the course of spore germination at five typical stages (i.e. mature spores, rehydrated spores, double-celled spores, germinated spores, and spores with protonemal cells). Proteomic analysis revealed 113 differentially expressed proteins, which were mainly involved in photosynthesis, reserve mobilization, energy supplying, protein synthesis and turnover, reactive oxygen species scavenging, signaling, and cell structure modulation. The presence of multiple proteoforms of 25 differentially expressed proteins implies that post-translational modification may play important roles in spore germination. The dynamic patterns of proteins and their encoding genes exhibited specific characteristics in the processes of cell division and rhizoid tip growth, which include heterotrophic and autotrophic metabolisms, de novo protein synthesis and active protein turnover, reactive oxygen species and hormone (brassinosteroid and ethylene) signaling, and vesicle trafficking and cytoskeleton dynamic. In addition, the function skew of proteins in fern spores highlights the unique and common mechanisms when compared with evolutionarily divergent spermatophyte pollen. These findings provide an improved understanding of the typical single-celled asymmetric division and polar growth during fern spore germination.

Surgical site infection after laparoscopic and open appendectomy: a multicenter large consecutive cohort study.

BACKGROUND: Laparoscopic appendectomy (LA) has been rapidly applied worldwide recently. The issue of surgical site infection (SSI) after appendectomy needs to be re-investigated and analyzed along with this trend. This study aimed to identify risk factors of SSI after appendectomy in recent years. METHODS: This retrospective study was conducted among patients with acute appendicitis who underwent either laparoscopic or open appendectomy (OA) at 7 general hospitals in China from 2010 to 2013. The incidence of SSI, classified as incisional SSI and organ/space SSI, was investigated. A multivariate logistic regression model was used to assess independent risk factors associated with overall, incisional, and organ/space SSI, respectively. RESULTS: Among 16,263 consecutive patients, 3,422 (21.0 %) and 12,841 (79.0 %) patients underwent LA and OA, respectively. The incidences of overall, incisional, and organ/space SSI were 6.2, 3.7, and 3.0 %, respectively. The proportion of LAs among both procedures increased yearly from 5.3 to 46.5 %, while the incidences of overall and incisional SSI after appendectomy simultaneously decreased yearly from 9.6 to 4.5 % and from 6.7 to 2.2 %, respectively. In comparison with OA, LA was associated with lower incidences of overall and incisional SSI (4.5 vs 6.7 %, P < 0.001; and 1.9 vs 4.2 %, P < 0.001), but a similar incidence of organ/space SSI (3.0 vs 3.0 %, P = 0.995). After multivariate logistic regression analyses were performed, LA was found to be independently associated with a decrease in development of overall SSI [odds ratio (95 % confidence interval) OR (95 % CI), 1.24 (1.03-1.70); P = 0.04] or incisional SSI [OR (95 % CI), 1.32 (1.10-1.68); P = 0.01]. CONCLUSION: With the increasing application trends of laparoscopic procedure, the incidence of SSI after appendectomy declined accordingly. Compared with OA, LA was independently associated with a significantly lower incidence of incisional SSI, but a similar incidence of organ/space SSI.

Casticin Attenuates Stemness in Cervical Cancer Stem-Like Cells by Regulating Activity and Expression of DNMT1.

OBJECTIVE: To explore whether casticin (CAS) suppresses stemness in cancer stem-like cells (CSLCs) obtained from human cervical cancer (CCSLCs) and the underlying mechanism. METHODS: Spheres from HeLa and CaSki cells were used as CCSLCs. DNA methyltransferase 1 (DNMT1) activity and mRNA levels, self-renewal capability (Nanog and Sox2), and cancer stem cell markers (CD133 and CD44), were detected by a colorimetric DNMT activity/inhibition assay kit, quantitative real-time reverse transcription-polymerase chain reaction, sphere and colony formation assays, and immunoblot, respectively. Knockdown and overexpression of DNMT1 by transfection with shRNA and cDNA, respectively, were performed to explore the mechanism for action of CAS (0, 10, 30, and 100 nmol/L). RESULTS: DNMT1 activity was increased in CCSLCs compared with HeLa and CaSki cells (P<0.05). In addition, HeLa-derived CCSLCs transfected with DNMT1 shRNA showed reduced sphere and colony formation abilities, and lower CD133, CD44, Nanog and Sox2 protein expressions (P<0.05). Conversely, overexpression of DNMT1 in HeLa cells exhibited the oppositive effects. Furthermore, CAS significantly reduced DNMT1 activity and transcription levels as well as stemness in HeLa-derived CCSLCs (P<0.05). Interestingly, DNMT1 knockdown enhanced the inhibitory effect of CAS on stemness. As expected, DNMT1 overexpression reversed the inhibitory effect of CAS on stemness in HeLa cells. CONCLUSION: CAS effectively inhibits stemness in CCSLCs through suppression of DNMT1 activation, suggesting that CAS acts as a promising preventive and therapeutic candidate in cervical cancer.

Ultrastructural and cytochemical studies on oogenesis of the fern Pteridium aquilinum.

Egg development in Pteridium aquilinum var. latiusculum was studied using ultrastructural and cytochemical methods to examine structural features influencing fertilization in leptosporangiate ferns. Ultrastructural observations indicate a separation cavity is first formed above the egg during oogenesis with a pore region persistently connecting the egg and the ventral canal cell. The egg envelope is formed by deposition of amorphous materials in the separation cavity on the outer surface of plasmalemma. The egg envelope was not formed across the pore region; instead, a fertilization pore was formed. During oogenesis, the egg nucleus produced extensive evaginations containing osmiophilic bodies. Cytochemical experiments revealed that the egg envelope displays strong periodic acid-Schiff reaction indicative of polysaccharides, with negligible Sudan black B staining for lipids, suggesting that the egg envelope is composed principally of polysaccharides, and not lipids. The present manuscript provides new insights into egg structure and development of Pteridium, including discovery and characterization of the fertilization pore and observations on the chemical nature of the egg envelope, thus contributing to the understanding of the cytological mechanism of the sexual reproduction of ferns.