Palladium-Catalyzed Synthesis, Acetylcholinesterase Inhibition, and Neuroprotective Activities of N-Aryl Galantamine Analogues.

A series of new N-aryl galantamine analogues (5a-5x) were designed and synthesized by modification of galantamine, using Pd-catalyzed Buchwald-Hartwig cross-coupling reaction in good to excellent yields. The cholinesterase inhibitory and neuroprotective activities of N-aryl derivatives of galantamine were evaluated. Among the synthesized compounds, the 4-methoxylpyridine-galantamine derivative (5q) (IC50 = 0.19 µM) exhibited excellent acetylcholinesterase inhibition activity, as well as significant neuroprotective effect against H2O2-induced injury in SH-SY5Y cells. Molecular docking, staining, and Western blotting analyses were performed to demonstrate the mechanism of action of 5q. Derivative 5q would be a promising multifunctional lead compound for the treatment of Alzheimer's disease.

Discovery of myrsinane-type Euphorbia diterpene derivatives through a skeleton conversion strategy from lathyrane diterpene for the treatment of Alzheimer's disease.

A series of novel myrsinane-type Euphorbia diterpene derivatives (1-37) were synthesized from the abundant natural lathyrane-type Euphorbia factor L3, using a multi-step chemical process guided by a bioinspired skeleton conversion strategy, with the aim of discovering potential anti-Alzheimer's disease (AD) bioactive lead compounds. The synthesis process involved a concise reductive olefin coupling reaction through an intramolecular Michael addition with a free radical, followed by a visible-light-triggered regioselective cyclopropane ring-opening. The cholinesterase inhibitory and neuroprotective activities of the synthesized myrsinane derivatives were evaluated. Most of the compounds showed moderate to strong potency, highlighting the importance of ester groups in Euphorbia diterpene. In particular, derivative 37 displayed the most potent acetylcholinesterase (AChE) inhibition, with an IC50 value of 8.3 µM, surpassing that of the positive control, tacrine. Additionally, 37 also showed excellent neuroprotective effect against H2O2-induced injury in SH-SY5Y cells, with a cell viability rate of 124.2% at 50 µM, which was significantly higher than that of the model group (viability rate 52.1%). Molecular docking, reactive oxygen species (ROS) analysis, immunofluorescence, and immunoblotting were performed to investigate the mechanism of action of myrsinane derivative 37. The results indicated that derivative 37 may be a promising myrsinane-type multi-functional lead compound for the treatment of Alzheimer's disease. Furthermore, a preliminary SAR analysis was performed to study the acetylcholinesterase inhibitory and neuroprotective activities of these diterpenes.

Synthesis, antiproliferative and anti-MDR activities of lathyrane diterpene derivatives based on configuration inversion strategy.

A series of lathyrane-type Euphorbia diterpene derivatives featured 3R configuration (H-3ß) were synthesized from natural rich Euphorbia factor L3via modified Mitsunobu reaction based on configuration inversion strategy. The antiproliferation activity and MDR reversal ability of the lathyrane derivatives were evaluated, and the most synthesized compounds showed moderate or strong potencies. Among them, diterpenes 21 (IC50 values of 2.6, 5.2 and 13.1 µM, respectively) and 25 (IC50 values of 5.5, 8.6 and 1.3 µM, respectively) presented the strong cytotoxicity against MCF-7, 4 T1 and HepG2 cells. Meanwhile, derivative 25 exhibited excellent MDR reversal ability with the reversal fold of 16.1 higher than that of verapamil. The cellular thermal shift assay and molecular docking proved direct engagement of diterpene 25 to ABCB1, suggesting 25 could be a promising MDR modulator. Furthermore, the preliminary SARs of these diterpenes were also discussed.

Dihydrotriazine derivatives display high anticancer activity and inducing apoptosis, ROS, and autophagy.

A series of dihydrotriazine derivatives bearing 5-aryloxypyrazole moieties were designed, and their anticancer activities against three human cancer cell lines (SGC-7901, HepG-2 and MCF-7) and one non-cancer cell line (LO2) were explored using the MTT assay in vitro. Most of the compounds exhibited potent antiproliferative activities against the three cancer cell lines, with compound 10e (IC50 = 2.12 µM) exhibiting the most potent antiproliferative activity against HepG-2 cells. Interestingly, autophagy was observed in the 10e-treated HepG-2 cells. Compound 10e also increased reactive oxygen species (ROS) levels and resulted in marked HepG-2 cells apoptosis. Further studies revealed that compound 10e could enhance the expression of Cl-PARP, Cl-caspase-3, and Cl-caspase-9. In addition, 10e triggered the formation of autophagosomes by promoting LC3-II and Beclin-1 expression. These results might be useful for exploring and developing dihydrotriazine derivatives as novel anticancer agents.

Production of polyhydroxyalkanoates by halotolerant bacteria with volatile fatty acids from food waste as carbon source.

In this study, a halotolerant strain was isolated from high salinity leachate and identified as Bacillus cereus NT-3. It can produce a high concentration of polyhydroxyalkanoates (PHAs) with no significant changes when NaCl concentration is up to 50 g/L. FTIR and NMR spectra of PHAs synthesized by Bacillus cereus NT-3 were similar to the standard or previous results. Effluent from acidogenic fermentation of food waste and pure volatile fatty acids (VFAs) mixture was used as carbon source to check the effect of non-VFAs compounds of the effluent on PHAs production. The maximum PHAs production was 0.42 g/L for effluent fermentation, whereas it was 0.34 g/L for pure VFAs fermentation, indicating that bacteria could use actual effluent in a better way. Furthermore, a mathematical model was established for describing kinetic behavior of bacteria using different carbon sources. These results provided a promising approach for PHAs biosynthesis with a low-cost carbon source.

Metabolomic insights into polyhydroxyalkanoates production by halophilic bacteria with acetic acid as carbon source.

A metabolomics method was established to analyze changes of intracellular metabolites and study the mechanism for enhancing polyhydroxyalkanoates production by halotolerant bacteria, Bacillus cereus strain HY-3, using acetic acid as carbon source. Maximum poly(3-hydroxybutyrate) (PHB) contents for the medium with 0.5 g/L and 5.0 g/L of acetic acid were 41.0 ± 0.415% and 49.2 ± 1.21%. Principal components analysis revealed clear metabolic differences in different growth stages and different concentrations of carbon source. According to statistical analysis, 3-hydroxybutyrate (3-HB), serine, threonine, malate, and pyruvate were determined as potential biomarkers for PHB production. Moreover, metabolic pathways analysis indicated that high level of 3-HB in death phase was due to the limitation of carbon source. Metabolism of glycine, serine, and threonine was influential pathway for PHB production among amino acid metabolisms. High levels of organic acids from the TCA cycle could stimulate the carbon source flux into PHB biosynthetic pathway.

Four new C20-diterpenoid alkaloids from Aconitum rotundifolium.

Four new C20-diterpenoid alkaloids, rotundifosines D-G (1-4), along with eight known ones (5-12) were isolated from the whole plant of Aconitum rotundifolium Kar. & Kir. The structures of the compounds were elucidated on the basis of spectroscopic analyses, including HR-ESI-MS and 1D, 2D NMR. Rotundifosine F (3) is a rare C20-diterpenoid alkaloid with quaternary ammonium salt. Alkaloids 1-4, 5, 6, 9, and 12 were evaluated for cytotoxicity against MCF-7, HCT-116 and HepG2 human cancer cell lines.

The 8th edition of the American Joint Committee on Cancer tumor-node-metastasis staging system for gastric cancer is superior to the 7th edition: results from a Chinese mono-institutional study of 1663 patients.

BACKGROUND: We investigated the superiority of the 8th edition of the tumor-node-metastasis (TNM) system for patients in China with gastric cancer. METHODS: The survival outcomes of 1663 patients with gastric cancer undergoing radical resection were analyzed. RESULTS: In the 8th edition system, homogeneous 5-year survival rates among different pathological TNM (pTNM) categories belonging to the same stage were observed. However, in the 7th edition system, the differences of 5-year survival rate among pTNM categories belonging to the same stage were observed in stages IIB (P = 0.010), IIIB (P = 0.004), and IIIC (P < 0.001). For patients in the pT1-3 (P < 0.001) and pT4a (P < 0.001) categories, there were significant differences in survival between patients in the pN3a and pN3b categories. Furthermore, partial cases (pT4bN0M0/T4aN2M0) of stage IIIB were downstaged to stage IIIA in the 8th edition system, and the 5-year survival rate of these patients was significantly better than that of patients in stage IIIB in the 8th edition system. Similarly, the 5-year survival rate of patients in p4bN2M0/T4aN3aM0 downstaged from stage IIIC to IIIB was significantly better than that of patients in stage IIIC. Compared with the 7th edition system, the 8th edition system had a higher likelihood ratio and linear trend chi-squared score and a smaller Akaike information criteria value. CONCLUSIONS: The 8th edition system is superior to the 7th edition system in terms of homogeneity, discriminatory ability, and monotonicity of gradients for Chinese patients with gastric cancer.

C18-Diterpenoid alkaloids from Delphinium anthriscifolium var. majus.

Five new C18-diterpenoid alkaloids, anthriscifoltines C-G (1-5), along with four known diterpenoid alkaloids anthriscifolcines C-F (6-9), were isolated from the extract of Delphinium anthriscifolium var. majus. Their structures were elucidated by extensive spectroscopic analyses (including 1D-, 2D-NMR, and HR-ESI-MS). Compounds 1-5 were also evaluated for their cytotoxic activity against MCF-7, HepG2, and H460 human cancer cell lines.

[Effect of MicroRNA-199 on Proliferation and Migration of Gastric Carcinoma Cells].

Objective To detect the expression of microRNA(miR)-199 in gastric carcinoma tissues and cell lines, and further explore the effect and molecular mechanism of miR-199 on the proliferation and migration of gastric carcinoma cell lines. Methods Reverse transcriptase-polymerse chain reaction was used to detect the expression of miR-199 in gastric carcinoma and adjacent normal tissue obtained from 51 patients and in gastric carcinoma cell lines and human gastric epithelial cell line GES-1. The gastric carcinoma cell lines over-expressing and low-expressing miR-199 were established to detect their proliferation and migration abilities. Dual-luciferase reporter assay was performed to detect the regulatory effect of miR-199 on the 3'untranslated region of TBL1XR1. Western blot was used to explore the miR-199-related mechanism. Results The relative expression of miR-199 in gastric carcinoma tissues was significantly lower than that in the adjacent normal tissue (0.2635±0.0303 vs. 1.6700±0.9613, t=13.95, P<0.001). The relative expressions of miR-199 in gastric carcinoma cell lines AGS (0.81, t=9.13, P<0.001), SGC-7901 (0.83, t=8.88, P<0.001), MKN28 (0.58, t=10.80, P<0.001), KATO-3 (0.60, t=10.31, P<0.001), MKN-45 (0.27, t=13.10, P<0.001) were significantly lower than that in the normal gastric cell line GES-1 (2.1). In miR-199 over-expressed cell lines, the cell proliferation and migration significantly decreased as compared with the control group of gastric carcinoma cells (731±13 vs. 345±18, t=24.90, P<0.001), and in miR-199 low-expressed group, the cell proliferation and migration increased compared with the control group of gastric carcinoma cells (257±16 vs. 657±8, t=32.59, P<0.001). Dual-luciferase reporter assay proved that miR-199 directly targeted on the 3' untranslated region of TBL1XR1. Western blot analysis showed that miR-199 inhibited the expression of TBL1XR1. Conclusion The over-expression of miR-199 in gastric carcinoma is associated with the decreased ability of proliferation and migration of gastric carcinoma cells by targeting TBL1XR1.

Prognostic significance of the total number of harvested lymph nodes for lymph node-negative gastric cancer patients.

BACKGROUND: The relationship between the number of harvested lymph nodes (HLNs) and prognosis of gastric cancer patients without an involvement of lymph nodes has not been well-evaluated. The objective of this study is to further explore this issue. METHODS: We collected data from 399 gastric cancer patients between November 2006 and October 2011. All of them were without metastatic lymph nodes. RESULTS: Survival analyses showed that statistically significant differences existed in the survival outcomes between the two groups allocated by the total number of HLNs ranging from 16 to 22. Therefore, we adopted 22 as the cut-off value of the total number of HLNs for grouping (group A: HLNs <22; group B: HLNs≥22). The intraoperative and postoperative characteristics, including operative blood loss (P=0.096), operation time (P=0.430), postoperative hospital stay (P=0.142), complications (P=0.552), rate of reoperation (P=0.966) and postoperative mortality (P=1.000), were comparable between the two groups. T-stage-stratified Kaplan-Meier analyses revealed that the 5-year survival rate of patients at the T4 stage was better in group B than in group A (76.9% vs. 58.5%; P=0.004). An analysis of multiple factors elucidated that the total number of HLNs, T stage, operation time and age were independently correlated factors of prognosis. CONCLUSIONS: Regarding gastric cancer patients without the involvement of lymph nodes, an HLN number ≥22 would be helpful in prolonging their overall survival, especially for those at T4 stage. The total number of HLNs was an independent prognostic factor for this population of patients.

The optimal extent of gastrectomy for middle-third gastric cancer: distal subtotal gastrectomy is superior to total gastrectomy in short-term effect without sacrificing long-term survival.

BACKGROUND: The optimal extent of gastrectomy for middle-third gastric cancer remains controversial. In our study, the short-term effects and longer-term survival outcomes of distal subtotal gastrectomy and total gastrectomy are analysed to determine the optimal extent of gastrectomy for middle-third gastric cancer. METHODS: We retrospectively collect and analyse clinicopathologic data and follow-up outcomes from a prospectively collected database at the Peking University Cancer Hospital. Patients with middle-third gastric adenocarcinoma who underwent curative resection are enrolled in our study. RESULTS: We collect data of 339 patients between January 2005 and October 2011. A total of 144 patients underwent distal subtotal gastrectomy, and 195 patients underwent total gastrectomy. Patients in the total gastrectomy group have longer operative duration (P < 0.001) and postoperative hospital stay (P = 0.001) than those in the distal subtotal gastrectomy group. In the total gastrectomy group, more lymph nodes are harvested (P < 0.001). Meanwhile, the rate of postoperative complications is lower in the distal subtotal gastrectomy group than in the total gastrectomy group (8% vs 15%, P = 0.047). Further analysis demonstrates that the rate of anastomosis leakage is lower in the distal subtotal gastrectomy group than in the total gastrectomy group (0% vs 4%, P = 0.023). Kaplan-Meier (log rank test) analysis shows a significant difference in overall survival between the two groups. The 5-year overall survival rates in the distal subtotal gastrectomy and total gastrectomy groups are 65% and 47%, respectively (P < 0.001). Further stage-stratified analysis reveals that no statistical significance exists in 5-year survival rate between the distal subtotal gastrectomy and total gastrectomy groups at the same stage. Multivariate analysis shows that age (P = 0.046), operation duration (P < 0.001), complications (P = 0.037), usage of neoadjuvant chemotherapy (P < 0.001), tumor size (P = 0.012), presence of lymphovascular invasion (P = 0.043) and N stage (P < 0.001) are independent prognostic factors for survival. CONCLUSIONS: For patients with middle-third gastric cancer, distal subtotal gastrectomy shortens the operation duration and postoperative hospital stay and reduces postoperative complications. Meanwhile, the long-term survival of patients with distal subtotal gastrectomy is similar to that of those with total gastrectomy at the same stage. The extent of gastrectomy for middle-third gastric cancer is not an independent prognostic factor for survival.

Diterpenoid Alkaloids from Two Aconitum Species with Antifeedant Activity against Spodoptera exigua.

Twenty-five diterpenoid alkaloids were isolated from the roots of two Aconitum species. The structures of seven new C19-diterpenoid alkaloids, apetaldines A-G (1-7), and 10 known alkaloids (8-17) from Aconitum apetalum and eight known alkaloids (18-25) from Aconitum franchetii var. villosulum were elucidated via HRESIMS, IR, and NMR data. Alkaloids 1-10, 15, 16, and 18-25 were screened for their antifeedant activity. Among the compounds tested, chasmanthinine (19) showed highly potent antifeedant activity with an effective concentration for 50% feeding reduction (EC50) at 0.07 mg/cm2. The antifeedant structure-activity relationship of the diterpenoid alkaloids is also discussed.

Five New C19 -Diterpenoid Alkaloids from Delphinium tianshanicum W.T.Wang.

Five new diterpenoid alkaloids, tianshanitines A-E (1 - 5), along with ten known compounds (6 - 15), were isolated from the EtOH extracts of the whole plant of Delphinium tianshanicum W.T.Wang. Their structures were determined based on extensive spectroscopic analyses, including 1D- and 2D-NMR, HR-ESI-MS, and the structure of tianshanitine C (3) was confirmed by X-ray diffraction analysis. Tianshanitine A (1) is the first example of natural diterpenoid alkaloid containing a benzoyl group at C(1) position. Tianshanitine B (2) is a rare natural diterpenoid alkaloid bearing a OH group at C(16) position. Compounds 1 - 5, 6, 8, 10, 12 and 14 were evaluated for cytotoxicity against HCT116, MCF-7 and HepG2 human cancer cell lines.

Trichostatin A potentiates TRAIL-induced antitumor effects via inhibition of ERK/FOXM1 pathway in gastric cancer.

Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is an ideal apoptosis inducer and believed to have promise in cancer therapy, yet part of cancer cells exhibit resistance to TRAIL-mediated apoptosis. This necessitates the exploration of agents that resensitizes cancer cells to TRAIL. In our study, we found that Trichostatin A (TSA), an histone deacetylase (HDAC) inhibitor, augmented TRAIL-induced apoptosis in gastric cancer cells in a caspase-dependent manner. Besides, upregulation of DR5 and downregulation of anti-apoptotic proteins including XIAP, Mcl-1, Bcl-2 and Survivin also contributed to this synergism. Noticeably, TSA treatment inhibited Forkhead boxM1 (FOXM1), which expression level showed negative correlation with TRAIL sensitivity. Similarly, silencing of FOXM1 by small interfering RNA (siRNA) resensitized cancer cells to TRAIL and strengthened the TRAIL-augmenting effect of TSA. In addition, we demonstrated the depletion of FOXM1 was a consequence of the inactivation of ERK mediated by TSA. Collectively, it was first shown that TSA potentiated TRAIL sensitivity via ERK/FOXM1 pathway in gastric cancer cells. FOXM1 might serve as a biomarker for predicting sensitivity to TRAIL.

A natural reassortant and mutant serotype 3 reovirus from mink in China.

Mammalian orthoreoviruses (MRVs) are widespread and infect virtually all mammals. We report here the first case of a natural mutant and reassortant serotype 3 reovirus from mink in China, known as MRV3 SD-14. Whole-genome sequence analysis showed that the MRV3 SD-14 may have resulted from a reassortment involving MRVs that infected swine, humans and mink. Interestingly, the S1 segment, which encodes the viral attachment protein σ1, which influences viral virulence and cell tropism in the host, had a stop codon mutation at amino acid 246. Surveillance of the virulence and evolution of MRVs in humans and other animals deserves more attention.

Recurrent amplification of MYC and TNFRSF11B in 8q24 is associated with poor survival in patients with gastric cancer.

BACKGROUND: Gastric cancer (GC) is an aggressive malignancy whose mechanisms of development and progression are poorly understood. The identification of prognosis-related genomic loci and genes may suffer from the relatively small case numbers and a lack of systematic validation in previous studies. METHODS: Array-based comparative genomic hybridization (aCGH) coupled with patient clinical information was applied to identify prognosis-related loci and genes with high-frequency recurrent gains in 129 GC patients. The candidate loci and genes were then validated using an independent cohort of 384 patients through branched DNA signal amplification analysis (QuantiGene assays). RESULTS: In the 129 patients, a copy number gain of three chromosome regions-namely, 8q22 (including ESRP1 and CCNE2), 8q24 (including MYC and TNFRSF11B), and 20q11-q13 (including SRC, MMP9, and CSE1L)--conferred poor survival for patients. In addition, the correlation between the branched DNA signal amplification analysis results and the aCGH results was analyzed in 73 of these 129 patients, and MYC, TNFRSF11B, ESRP1, CSE1L, and MMP9 were found to be well correlated. Further validation using an independent cohort (n = 384) verified that only MYC and TNFRSF11B within 8q24 are related to survival. Patients with gains in both MYC and TNFRSF11B had poorer survival than those with no gains, particularly those with noncardia GC. Gains in both of these genes were also a significant independent prognostic indicator. CONCLUSIONS: Our results revealed that copy number gains in MYC and TNFRSF11B located at 8q24 are associated with survival in GC, particularly noncardia GC.

Neoadjuvant chemoradiation therapy for resectable esophago-gastric adenocarcinoma: a meta-analysis of randomized clinical trials.

BACKGROUND: The efficacy and safety of preoperative chemoradiation therapy (CRT) for advanced esophago-gastric adenocarcinoma are still in question, and the prognosis of these patients is poor. METHODS: We systematically searched electronic databases from January 1990 to July 2014. The primary outcome was overall survival. The secondary outcomes were a R0 resection rate, positive rate of lymph node metastasis, postoperative recurrence rate, pathological complete response (pCR) rate and perioperative mortality. Overall survival was measured with a hazard ratio (HR), while other secondary outcomes were measured with an odds ratio (OR). RESULTS: Seven randomized controlled trials (RCTs) including 1085 patients were searched and, of these, 869 had adenocarcinoma. Patients receiving preoperative CRT had a longer overall survival (HR 0.74; 95% confidence interval (CI) 0.63-0.88), higher likelihood of R0 resection and greater chance of pCR, while they had a lower likelihood of lymph node metastasis and postoperative recurrence. The difference of perioperative mortality was non-significant. In addition, the result of the comparison between preoperative CRT and preoperative chemotherapy (CT) in two RCTs was non-significant. CONCLUSION: Patients with resectable esophago-gastric adenocarcinoma can gain a survival advantage from preoperative CRT. However, limited to the number of RCTs, the effect of adding radiotherapy to preoperative CT separately is still uncertain and more high-quality prospective trials are needed.

Novel circovirus from mink, China.

A long-established epidemic of enteritis, caused by an unidentified pathogen distinct from parvovirus, has now been recognized in mink. In 2013, we identified a novel circovirus by degenerate PCR and fully sequenced its genome. This virus differs substantially from currently known members of the genus Circovirus and represents a new species.

Pyridostigmine attenuates hypertension by inhibiting activation of the renin-angiotensin system in the hypothalamic paraventricular nucleus.

Activation of the renin-angiotensin system (RAS) triggers oxidative stress and an inflammatory response in the hypothalamic paraventricular nucleus (PVN), in turn increasing the sympathetic hyperactivity that is a major cause of hypertension. Pyridostigmine has cardioprotective effects by suppressing the RAS of myocardial tissue. However, whether pyridostigmine attenuates hypertension by inhibiting the RAS of the PVN remains unclear. We thus investigated the effect and mechanism of pyridostigmine on two-kidney one-clip (2K1C)-induced hypertension. 2K1C rats received pyridostigmine, or not, for 8 weeks. Cardiovascular function, hemodynamic parameters, and autonomic activity were measured. The PVN levels of pro-/anti-inflammatory cytokines, oxidative stress, and RAS signaling molecules were evaluated. Our results showed that hypertension was accompanied by cardiovascular dysfunction and an autonomic imbalance characterized by enhanced sympathetic but diminished vagal activity. The PVN levels of interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), reactive oxygen species (ROS), NOX-2, and malondialdehyde (MDA) increased; those of IL-10 and superoxide dismutase (SOD) decreased. Moreover, the RAS signaling pathway was activated, as evidenced by increased levels of the angiotensin-converting enzyme (ACE), angiotensin II (Ang II), and the Ang II type 1 receptor (AT1R) and a decreased AT2R level. Pyridostigmine lowered blood pressure and improved cardiovascular function, associated with restoration of the autonomic balance. Meanwhile, pyridostigmine decreased PVN IL-6, TNF-α, ROS, NOX-2, and MDA levels and increased IL-10 and SOD levels. Additionally, pyridostigmine suppressed PVN ACE, Ang II, and AT1R levels and increased AT2R expression. Pyridostigmine attenuated hypertension by inhibiting PVN oxidative stress and inflammation induced by the RAS.