-
Fowler Kerr posted an update 3 weeks, 4 days ago
V.Envenomation by Naja annulifera (snouted cobra), a non-spitting African cobra, can result in local tissue damage and fatal paralysis but a species-specific antivenom treatment is currently lacking. In this study, we investigated the quantitative proteome of N. annulifera venom, incorporating HPLC and LC-MS/MS to elucidate the venom toxicity. The immunoreactivities and in vivo neutralization activities of two hetero-specific antivenom products (Premium Serums Pan Africa polyvalent antivenom, PANAF and VINS African polyvalent antivenom, VAPAV) against the venom were subsequently examined. N. annulifera venom comprises 10 toxin families, with three-finger toxin (3FTx) being the most abundantly expressed (~78%). Within 3FTx, cytotoxin is the most dominant form and made up three-quarter of the venom bulk (~74%), whereas alpha-neurotoxins constitute less then 4% of the total venom proteins. Phospholipase A2 was undetected in the venom proteome, consistent with the unusual absence of PLA2 from the venoms of cobras in the Uraeus subgenus. In ELISA, PANAF and VAPAV showed comparable immunoreactivity toward the protein antigens of N. annulifera venom. These antivenoms, despite being raised against hetero-specific venoms, were capable of cross-neutralizing the lethal effect of N. annulifera venom in mice, with PANAF being marginally more potent. V.The purpose of this study was to investigate the influences of the polysaccharides derived from Glycyrrhiza uralensis Fisch. (GCPs) on aconitine (AC), hypaconitine (HA), and benzoylmesaconine (BMA) from Aconitum carmichaelii Debx. and to explore potential interaction mechanisms. Biopharmaceutical properties in vitro including stability, aqueous solubility and permeability were determined by UPLC. Pharmacokinetic parameters in vivo were determined using UPLC-MS/MS. Tenalisib Phase solubility analysis, UV-vis spectrophotometry and differential scanning calorimetry (DSC) were used to explore potential interaction mechanisms. The results showed that GCPs could increase the stabilities of three alkaloids and solubilities of AC and HA, significantly decrease permeabilities of three alkaloids. The pharmacokinetic studies demonstrated that, after combination with GCPs, AC exhibited a higher Cmax value, shorter t0.5, higher elimination rate and greater area under the concentration-time curve (AUC) value compared to free AC. GCPs also improved the Cmax, t0.5, AUC(0-tn) and AUC(0-∞) values of HA to play a therapeutic role, and improved the t0.5 and AUC(0-∞) values of BMA to prolong the pharmacological effect and increase bioavailability. In addition, the results for the apparent formation constants and DSC analysis showed that an inclusion complex could be formed between GCPs and AC, GCPs and HA, and GCPs and BMA. V.The indicator-based nucleic acid detection protocol is one of the major approaches to monitor the sequence-selective nucleic acid hybridization-mediated recognition events in biochemical analysis. The metal complex, cobalt phenanthroline, [Co(phen)33+], which is one of the electroactive indicators, interacts more with double stranded nucleic acids via intercalation. Thus, this interaction permits an increase at the electrochemical signal of [Co(phen)33+]. In our study, the interaction of metal complex, [Co(phen)33+] with nucleic acids was examined using pencil graphite electrodes (PGEs) in combination with differential pulse voltammetry (DPV) technique. The voltammetric detection of miRNA-34a was investigated based on the changes at the electrochemical signal of [Co(phen)33+] under optimized experimental conditions; such as modulation amplitude, accumulation potential, accumulation time of metal complex and DNA probe concentration, hybridization time, target miRNA concentration. Furthermore, the selectivity of electrochemical miRNA-34a biosensor was studied in contrast to different miRNAs. The applicability of indicator-based biosensor specific to miRNA-34a was also presented by using total RNA samples. V.Polysaccharides have various biological activities, such as antioxidant, anti-tumor, antiviral, anti-aging, anti-inflammatory, anti-radiation, hypoglycemic and lipid lowering, immune regulation, etc. Although many polysaccharides have been proved to have various biological activities, in the research process, it has been found that more polysaccharides in nature do not have biological activities or have low activities, and some polysaccharides have poor activities due to lack of certain groups. While others are due to polysaccharide with too large molecular weight, because its molecular weight is too large to smoothly enter cells and thus cannot exert its activity. For the former, we need to adopt molecular grafting modification. This kind of modification method is mainly chemical modification method, which increases the functional groups and molecular weight of various polysaccharides to improve their biological activity. For the latter, we need to adopt molecular degradation modification, which includes biodegradation, physical degradation, chemical degradation and other means to improve the solubility of polysaccharide in water phase by reducing its molecular weight, thus improving its activity. This article mainly introduces polysaccharide structure modification methods that have been widely used in recent years. Two acid polysaccharides were obtained from steamed ginseng (GPS-1 and GPS-2) through water extraction, ion-exchange chromatography and gel chromatography. The structural features and ability of the polysaccharides to inhibit lipid accumulation in oleic acid-induced HepG2 cells were studied. GPS-1 consisted of type I arabinogalactans (AG-I), arabinogalactans-II (AG-II) and rhamnogalacturonan I (RG-I) domains. GPS-2 was a pectin-like polysaccharide consisting mainly of the homogalacturonan (HG) domain and a small amount of AG domain. Both GPS-1 and GPS-2 had branches attaching on O-3 of (1 → 6)-GalA or O-4 of (1 → 2)-Rha and terminated by either Ara or Gal. An in vitro experiment revealed that GPS-1 treatment at 50-400 μg/ml could dose-dependently decrease intracellular lipid accumulation and cholesterol (TC) and triglycerides (TG) levels. GPS-1 exerted a more serious hypolipidemic effect than GPS-2 did. Moreover, GPS-1 considerably increased the phosphorylation of AMP-activated protein kinase (AMPK) and affected the expression of AMPK downstream targets, including the inhibition of the protein expression of sterol regulatory element-binding protein 1c (SREBP-1c) and activation of Acetyl-CoA carboxylase (ACC).