ANTI-PROLIFERATIVE WITHANOLIDES FROM VASSOBIA BREVIFLORA AND WITHANIA SOMNIFERA

In order to identify anti-proliferative compounds from selected Latin American plants, approximately 200 plant extracts were screened by the MTS assay (3-[4,5-dimethylthiazol-2yl]-5-[3-carboxymethoxyphenyl]-2-[4-sulfophenyl]-2H tetrazolium). Vassobia breviflora (Solanaceae), was identified as the most active of the species tested in this study. Following a bioassay-guided approach, withaferin A was isolated and characterized. This withanolide-type steroidal lactone showed anti-proliferative activities with IC50 values from 0.5 to 2.2 μM against head and neck squamous cell carcinoma (HNSCC) MDA1986, JMAR, UM-SCC-2 and JHU011. A mechanistic study showed that withaferin A induced apoptosis and cell death in HNSCC cells as well as a shift from G0/G1 to G2/M arrest in cell cycle studies. Western data demonstrated that the anti-proliferative action of withaferin A could be in part explained through degradation of total Akt levels as well as decrease in activation of Akt levels. In order to establish anticancer structure activity relationships, three analogues were semi-synthesized from withaferin A, and ten related withanolides, including a new chlorinated withanolide 6α-chloro-5β,17α-dihydroxywithaferin, were isolated from Withania somnifera (Solanaceae). All structures were elucidated on the basis of spectroscopic methods (IR, MS, and 1D/2D NMR). X-ray crystallography confirmed the absolute configuration of the new withanolide. A method for large-scale isolation of withaferin A from W. somnifera was also developed and presented

Chlorinated Withanolides from Withania somnifera

A chlorinated withanolide, 6α-chloro-5β,17α-dihydroxywithaferin A (1), and nine known withanolides, 6α-chloro-5β-hydroxywithaferin A (2), (22R)-5β-formyl-6β,27-dihydroxy-1-oxo-4-norwith-24-enolide, withaferin A, 2,3-dihydrowithaferin A, 3-methoxy-2,3-dihydrowithaferin A, 2,3-didehydrosomnifericin, withanone, withanoside IV and withanoside X, were isolated from Withania somnifera (Solanaceae). All structures were elucidated on the basis of spectroscopic methods (IR, HRESIMS, 1D/2D NMR). X-ray crystallography confirmed the absolute configuration of 1

A Review of the Seventh Forum of the World Association for Political Economy

After the world economic crisis broke out in 2008, some developed capitalist countries adopted right-wing policies to rob the poor for the rich, at the expense of developing countries with no concern over the ecological environment. They succeeded in helping the giant financial capitalists, but exacerbated the governmental debt crisis, and did little to relieve the unemployment crisis. They have increased the suffering of the majority of workers, did harm to the long-term ecological environment, and consequently caused the resistance and protest of workers at home and abroad. It has also forced developing countries to strengthen cooperation between each other, especially among the BRICS countries, and caused people to think about alternative institutions and specific programs which are better for ecology and human development. To that end, the World Association for Political Economy (WAPE) held the 7th Forum to make in-depth discussion on these issues

Globalization, Employment and Agriculture: A Review of the Eleventh Forum of the World Association for Political Economy

Economic globalization has greatly affected the economy, society and other aspects of individual countries and the world as a whole. As is well known, agriculture is the important foundation of the global economy, and most developing countries have a large rural population where agriculture is a significant part of the economy. Employment is the foundation of people's livelihood and full employment is difficult to achieve. Therefore, the study of how economic globalization affects agriculture and employment, and how developing countries and socialist countries should respond rationally and effectively, is worthy of attention

Restoring Vision in Hazy Weather with Hierarchical Contrastive Learning

Image restoration under hazy weather condition, which is called single image dehazing, has been of significant interest for various computer vision applications. In recent years, deep learning-based methods have achieved success. However, existing image dehazing methods typically neglect the hierarchy of features in the neural network and fail to exploit their relationships fully. To this end, we propose an effective image dehazing method named Hierarchical Contrastive Dehazing (HCD), which is based on feature fusion and contrastive learning strategies. HCD consists of a hierarchical dehazing network (HDN) and a novel hierarchical contrastive loss (HCL). Specifically, the core design in the HDN is a hierarchical interaction module, which utilizes multi-scale activation to revise the feature responses hierarchically. To cooperate with the training of HDN, we propose HCL which performs contrastive learning on hierarchically paired exemplars, facilitating haze removal. Extensive experiments on public datasets, RESIDE, HazeRD, and DENSE-HAZE, demonstrate that HCD quantitatively outperforms the state-of-the-art methods in terms of PSNR, SSIM and achieves better visual quality.Comment: 30 pages, 10 figure

The October Revolution: Promoting the Development of World Economy and Improving People's Livelihood: A Review of the Twelfth Forum of the World Association for Political Economy

The October Revolution, as the first successful proletarian revolution, broke up the capitalist world system, established the first socialist state and opened up a new era in human history. It represents the beginning of the transition of human society from capitalism to socialism, and is therefore worthy of special commemoration. While Marx and Engels turned socialism from the utopian one into the scientific one, it was the October Revolution that turned socialism from theory into practice. Marxists need to firmly continue the march along the socialist road that it opened up, with perseverance in the difficult and tortuous path, and with continuous exploration in revolution and reform. We must experiment with various ways to transform the capitalist system, innovate and improve the socialist system, develop and achieve a prosperous socialist economy, and fight for the establishment of the communist community and stateless world for mankind

A Review of the Eighth Forum of the World Association for Political Economy

There are many kinds of inequalities such as inequalities between nations, gender inequalities, racial inequalities, and especially income and wealth inequalities, which are emerging as the most important ones in the current global crisis of capitalism. Also, the latest historic crisis of capitalism has led to a decline in the levels of growth in the world, especially in Europe, with enormous social consequences. The response of the dominant classes in these countries to these problems has been the imposition of austerity policies. These policies instead of reducing unemployment and improving living standards have increased the reach of private capitalist activities. In May of 2013, WAPE held its Eighth Forum themed “Inequalities and World Capitalism: Analysis, Policy and Action.” The aim is to analyze the reasons for world inequality and counter measures against it, find the conditions of the world development from the radical perspective through renewed study of the finished and unfinished writings of Marx and of the plural realities of our time

Withaferin A, a Cytotoxic Steroid from Vassobia breWiflora, Induces Apoptosis in Human Head and Neck Squamous Cell Carcinoma

As part of a program to discover drug leads from plant biodiversity, the present investigation was undertaken to explore the anticancer potential of compounds derived from selected Latin American plants. Bioassay-guided fractionation of a crude extract of the aerial parts of Vassobia breviflora led to the isolation of the withanolide-type steroidal lactone withaferin A (1). This compound was tested for antiproliferative activity against the head and neck squamous cell carcinoma (HNSCC) cell lines, MDA1986, JMAR, UM-SCC-2, and JHU011. The inhibitory concentrations to reduce cell viability to 50% (IC50) were determined by the MTS cytotoxicity assay, and 1 reduced cell viability with IC50 values in the range 0.5−2.2 μM. A mechanistic study showed that 1 induces apoptosis and cell death in HNSCC cells as well as a cell-cycle shift from G0/G1 to G2/M. Cells treated with 1 exhibited inactivation of Akt and a reduction in total Akt concentration. This investigation constitutes the first report of the antiproliferative activity of withaferin A (1) against head and neck squamous carcinoma

Cytotoxic Oleanane-type Triterpenen Saponins with N-acetyl Sugar from Albizia inundata [abstract]

Comparative Medicine - OneHealth and Comparative Medicine Poster SessionBioassay-guided fractionation of a CH2Cl2-MeOH extract of the aerial part of Albizia inundata , collected in Argentina, resulted in the isolation of two new oleanane-type triterpene saponins with N-acetyl sugar (1, 2) and seven known saponins (3-9). Their structures were established on the basis of extensive 2D NMR (HSQC, COSY or DQF-COSY, TOCSY, HMBC), ESIMS and chemical methods. Saponins 1-4 showed cytotoxicity against the in JMAR, MDA 1986, UM-SCC-2 and JHU011 human head and neck squamous cells using the MTS assay

Allelic shift in cis-elements of the transcription factor RAP2.12 underlies adaptation associated with humidity in Arabidopsis thaliana

Populations of widespread species are usually geographically distributed through contrasting stresses, but underlying genetic mechanisms controlling this adaptation remain largely unknown. Here, we show that in Arabidopsis thaliana, allelic changes in the cis-regulatory elements, WT box and W box, in the promoter of a key transcription factor associated with oxygen sensing, RELATED TO AP 2.12 (RAP2.12), are responsible for differentially regulating tolerance to drought and flooding. These two cis-elements are regulated by different transcription factors that downstream of RAP2.12 results in differential accumulation of hypoxia-responsive transcripts. The evolution from one cis-element haplotype to the other is associated with the colonization of humid environments from arid habitats. This gene thus promotes both drought and flooding adaptation via an adaptive mechanism that diversifies its regulation through noncoding alleles