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Zeng N.-K.,CAS Kunming Institute of Botany | Zeng N.-K.,Hainan Medical University | Cai Q.,CAS Kunming Institute of Botany | Yang Z.L.,CAS Kunming Institute of Botany

Corneroboletus was erected in the Boletaceae to accommodate Boletus indecorus originally described from southeastern Asia. The mucilaginous surface of the basidioma, the ixohyphoepithelium pileipellis and the irregularly warty to irregularly bacillate ornamentation of basidiospores distinguish this fungus from other described species in Boletaceae. Phylogenetic placement of this fungus was investigated further with molecular data including LSU rRNA and concatenated alignment of nrLSU, 5.8S rRNA and rpb2 genes, and an independent lineage among existing genera of Boletaceae was suggested by our phylogenetic results. Consequently a description, illustrations and a comparison of Corneroboletus with allied taxa are presented. © 2012 by The Mycological Society of America. Source

Lin Y.S.,Hainan Medical University
Zhonghua gan zang bing za zhi = Zhonghua ganzangbing zazhi = Chinese journal of hepatology

To explore the mechanism of Alpha-fetoprotein (AFP) effects on hepatocellular carcinoma cells (HCC) resistances apoptosis induced by tumor necrosis factor-related apoptosis inducing-ligand (TRAIL). The expressed alteration of TRAIL receptor-2 (DR5) after the human hepatoma cells line Bel 7402 (AFP-producing) and HLE cells (non-AFP producing) were treated with all trans retinoic acid (ATRA) were determined by Western blot; Interaction of AFP with RAR-beta was analyzed by co-immunoprecipitation (Co-IP); Laser confocal microscopy was used to observe co-localization of AFP and RAR-beta; Short small RNA interfering (RNAi) was applied to knock down the expression of AFP in Bel 7402 cells; The full AFP gene cDNA was inserted into pcDNA3.1 vector and constructed the expressed vector of AFP (named pcDNA3.1-afp); The growth of hepatoma cells was analyzed by MTT. Bel 7402 and HLE cells expressed DR5, lowed dosage of ATRA (40mumol/L) had no influence on the expression of DR5 in Bel 7402 cells, but ATRA (160mumol/L) could inhibit the expression of AFP and promote the expression of DR5 significantly; Co-IP indicated that AFP had a property for interacting with RAR-beta; The results also demonstrated AFP co-localization with RAR-beta in cytoplasm of Bel 7202 cells; The expression of DR5 was enhanced while the expression of AFP was knocked down by RNAi. pcDNA3.1-afp vector was transfected into HLE cells, the growth of HLE cells were stimulated and TRAIL cytotoxicity of HLE cells were reduced. But when the expression of AFP was knocked down the sensitivity of Bel 7402 cells to TRAIL was enhanced. These data provided that AFP had a capability to interact with RAR-beta and suppressed the expression of DR5. AFP could play pivotal role on hepatoma cells resistance-induced apoptosis by TRAIL. Source

Yu K.,CAS Shanghai Institute of Materia Medica | Chen F.,CAS Shanghai Institute of Materia Medica | Chen F.,Hainan Medical University | Li C.,CAS Shanghai Institute of Materia Medica
Current Drug Metabolism

Saponins are a group of amphiphilic glycosides containing one or more sugar chains linked to a nonpolar triterpene or steroid aglycone skeleton, which are believed to be responsible for the pharmacological activities of many Chinese medicinal herbs. The purpose of this paper is to summarize the contemporary knowledge of the absorption, disposition, and pharmacokinetics of some important saponins, including ginsenosides, licorice saponins, dioscorea saponins, astragalosides, and saikosaponins. Poor intestinal absorption of saponins is mainly due to their unfavorable physicochemical traits, such as large molecular mass (>500 Da), high hydrogen-bonding capacity (>12), and high molecular flexibility (>10), that underlie poor membrane permeability. Rapid and extensive biliary excretion is another primary factor that limits the oral bioavailability of most saponins. However, several saponins, including ginsenosides Ra 3, Rb 1, Rc, and Rd, and dioscin, are excreted slowly into the bile and in turn have significantly long elimination half lives (7-25 h in rats). These longcirculating saponins may be used as pharmacokinetic markers to substantiate systemic exposure to the ingested herb extracts. In addition to biliary excretion for elimination of most saponins unchanged, renal excretion may also be important for certain saponins. Saponins can be hydrolyzed by the colonic microflora. After absorption, the deglycosylated aglycones undergo phase I and/or II metabolism by the host. In line with the poor permeability, saponin concentrations in most rat tissues are lower than the concurrent plasma level and the brain level is usually very low. However, the liver concentrations of many saponins, as well as the kidney levels of certain saponins, can be quite high, which involves transporter-mediated uptake mechanisms. Repeated p.o. ingestion of glycyrrhizin appears to be able to induce CYP3A in rodents and humans, while several deglycosylated products of ginsenosides can moderately inhibit CYP activities in vitro with IC 50 values of 10-50 μM. More research is required for elucidation of the absorption, disposition, and pharmacokinetics of multiple saponins to enhance understanding which saponins are most likely to exert pharmacological effects in vivo, as well as influence of complex herb matrix. In addition, research is also needed to characterize the microbiotal deglycosylation and the subsequent aglycone metabolism by the host for a broader range of saponins, as well as the hepatobiliary transporter phenotyping for and the interaction with saponins. Furthermore, in vitro and in vivo studies of saponin-based herb-drug interactions are also warranted. © 2012 Bentham Science Publishers. Source

Wiwanitkit S.,Wiwanitkit House | Wiwanitkit V.,Hainan Medical University
Asian Pacific Journal of Tropical Biomedicine

Ebola virus outbreak in Africa in 2014 is a big global issue. The vaccine is the hope for management of the present outbreak of Ebola virus infection. There are several ongoing researches on new Ebola vaccine. In this short manuscript, we discuss and put forward specific remained problems to be answered on this specific issue. Lack for complete knowledge on the new emerging virus, concern from pharmaceutical company and good trial of new vaccine candidates are the remained problem to be further discussed in vaccinology. © 2015 by the Asian Pacific Journal of Tropical Biomedicine. Source

Wiwanitkit S.,Wiwanitkit House | Wiwanitkit V.,Hainan Medical University
North American Journal of Medical Sciences

Pyogenic brain abscess is important in neurology. This infectious disease is fatal and the management is usually complicated. Here, the authors review and discuss the clinical aspects of pyogenic brain abscess found in the earlier reports from a tropical setting in Thailand. The literature review was compiled through standard reference database searching and the derived publications were further extracted to obtain clinical data. The main clinical characteristics of pyogenic brain abscess in this setting were similar to others. However, there are some specific characteristics on the nature of tropical setting. Source

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