Bergenin suppresses the growth of colorectal cancer cells by inhibiting PI3K/AKT/mTOR signaling pathway

Purpose: To investigate anticancer effects of bergenin on human colorectal cancer cell lines.Methods: Human colorectal adenocarcinoma cell line HCT116 was treated with various concentrations of bergenin for 24 and 48 h. Cell viability, apoptosis, cell cycle arrest and reactive oxygen species (ROS) level were analyzed by MTT, flow cytometry and fluorescent dye assays, respectively. DNA damage-associated protein expressions were analyzed by Western blotting.Results: Bergenin significantly suppressed the viability of HCT116 cells. Moreover, bergenin induced cells to accumulate in G1 phase and resulted in DNA breaks in HCT116 cells. It also led to marked accumulation of intracellular reactive oxygen species (ROS), a breaker of DNA strand in HCT116 cells. Interestingly, bergenin inhibited PI3K/AKT/mTOR pathway.Conclusion: Bergenin effectively suppresses the growth of colorectal  adenocarcinoma by inducing generation of intracellular ROS, DNA damage and consequent G1 phase arrest via inhibition of PI3K/AKT/mTOR pathway.Keywords: Bergenin, Colorectal cancer, DNA damage, Cell cycle arrest,  PI3K/AKT/mTO

Electronically phase separated nano-network in antiferromagnetic insulating LaMnO3/PrMnO3/CaMnO3 tricolor superlattice

Strongly correlated materials often exhibit an electronic phase separation (EPS) phenomena whose domain pattern is random in nature. The ability to control the spatial arrangement of the electronic phases at microscopic scales is highly desirable for tailoring their macroscopic properties and/or designing novel electronic devices. Here we report the formation of EPS nanoscale network in a mono-atomically stacked LaMnO3/CaMnO3/PrMnO3 superlattice grown on SrTiO3 (STO) (001) substrate, which is known to have an antiferromagnetic (AFM) insulating ground state. The EPS nano-network is a consequence of an internal strain relaxation triggered by the structural domain formation of the underlying STO substrate at low temperatures. The same nanoscale network pattern can be reproduced upon temperature cycling allowing us to employ different local imaging techniques to directly compare the magnetic and transport state of a single EPS domain. Our results confirm the one-to-one correspondence between ferromagnetic (AFM) to metallic (insulating) state in manganite. It also represents a significant step in a paradigm shift from passively characterizing EPS in strongly correlated systems to actively engaging in its manipulation

One-Step Photocontrolled Polymerization-Induced Self-Assembly (Photo-PISA) by Using In Situ Bromine-Iodine Transformation Reversible-Deactivation Radical Polymerization

Polymerization-induced self-assembly (PISA) has become an effective strategy to synthesize high solid content polymeric nanoparticles with various morphologies in situ. In this work, one-step PISA was achieved by in situ photocontrolled bromine-iodine transformation reversible-deactivation radical polymerization (hereinafter referred to as Photo-BIT-RDRP). The water-soluble macroinitiator precursor α-bromophenylacetate polyethylene glycol monomethyl ether ester (mPEG1k-BPA) was synthesized in advance, and then the polymer nanomicelles (mPEG1k-b-PBnMA and mPEG1k-b-PHPMA, where BnMA means benzyl methacrylate and HPMA is hydroxypropyl methacrylate) were successfully formed from a PISA process of hydrophobic monomer of BnMA or HPMA under irradiation with blue LED light at room temperature. In addition, the typical living features of the photocontrolled PISA process were confirmed by the linear increase of molecular weights of the resultant amphiphilic block copolymers with monomer conversions and narrow molecular weight distributions (Mw/Mn < 1.20). Importantly, the photocontrolled PISA process is realized by only one-step method by using in situ photo-BIT-RDRP, which avoids the use of transition metal catalysts in the traditional ATRP system, and simplifies the synthesis steps of nanomicelles. This strategy provides a promising pathway to solve the problem of active chain end (C-I) functionality loss in two-step polymerization of BIT-RDRP

Zinc Phthalocyanine Covalent Polymers as Recyclable Catalysts for NIR-Photocontrolled RAFT Polymerization in Water

An excellent catalyst plays key roles and is always pursued by researchers for various controlled polymerizations. In this work, flexible triethylene glycol is used for the first time to bridge zinc phthalocyanine to form zinc phthalocyanine covalent polymers (ZnPc-CPs) as highly efficient heterogeneous photocatalysts for the generation of singlet oxygen (1O2) and thereafter to catalyze an aqueous reversible addition–fragmentation chain transfer polymerization under irradiation with near-infrared (NIR) LED light (λmax = 730 nm) at room temperature. The oxygen content is crucial to the polymerization. Trace oxygen in the polymerization produces an active hydrogen peroxide initiator to accelerate the polymerization, while a large amount of oxygen will terminate the polymerization. Additionally, benefiting from the high penetrating power of NIR light, the polymerization can still proceed in the presence of barriers. More importantly, compared to homogeneous photocatalysts, heterogeneous ZnPc-CPs can be reused by simple post-treatment and recycled without a significant decrease in the catalytic efficiency. The significant advantages, including employing NIR LED light irradiation, water as a solvent, a recyclable heterogeneous photocatalyst, and no need of prior deoxygenation, make this polymerization system not only easy to manipulate but also highly economical and environmentally beneficial

Total HIV/AIDS expenditures in Dehong Prefecture, Yunnan province in 2010: the first systematic evaluation of both health and non-health related HIV/AIDS expenditures in China.

We assessed HIV/AIDS expenditures in Dehong Prefecture, Yunnan Province, one of the highest prevalence regions in China, and describe funding sources and spending for different categories of HIV-related interventions and at-risk populations.2010 HIV/AIDS expenditures in Dehong Prefecture were evaluated based on UNAIDS' National AIDS Spending Assessment methodology.Nearly 93% of total expenditures for HIV/AIDS was contributed by public sources. Of total expenditures, 52.7% was allocated to treatment and care, 24.5% to program management and administration and 19.8% to prevention. Spending on treatment and care was primarily allocated to the treatment of opportunistic infections. Most (40.4%) prevention spending was concentrated on most-at-risk populations, injection drug users (IDUs), sex workers, and men who have sex with men (MSM), with 5.5% allocated to voluntary counseling and testing. Prevention funding allocated for MSM, partners of people living with HIV and prisoners and other confined populations was low compared to the disproportionate burden of HIV/AIDS in these populations. Overall, people living with HIV accounted for 57.57% of total expenditures, while most-at-risk populations accounted for only 7.99%.Our study demonstrated the applicability of NASA for tracking and assessing HIV expenditure in the context of China, it proved to be a useful tool in understanding national HIV/AIDS response from financial aspect, and to assess the extent to which HIV expenditure matches epidemic patterns. Limited funding for primary prevention and prevention for MSM, prisoners and partners of people living with HIV, signal that resource allocation to these key areas must be strengthened. Comprehensive analyses of regional and national funding strategies are needed to inform more equitable, effective and cost-effective HIV/AIDS resource allocation

Comparison between HIV prevalence and proportional spending for HIV/AIDS beneficiary populations in Dehong Prefecture in 2010.

<p>Comparison between HIV prevalence and proportional spending for HIV/AIDS beneficiary populations in Dehong Prefecture in 2010.</p

2010 HIV/AIDS Beneficiary Populations in Dehong Prefecture.

<p>2010 HIV/AIDS Beneficiary Populations in Dehong Prefecture.</p

Flow of HIV/AIDS expenditures in Dehong Prefecture, 2010.

<p>Flow of HIV/AIDS expenditures in Dehong Prefecture, 2010.</p