Pharmacokinetics of (-)-epigallocatechin-3-gallate in conscious and freely moving rats and its brain regional distribution

A liquid chromatography technique coupled with tandem mass spectrometry (LC-MS/MS) electrospray ionization was used to measure (-)-epigallocatechin-3-gallate (EGCG) in rat plasma. This method was applied to investigate the pharmacokinetics of EGCG in a conscious and freely moving rat by an automated blood sampling device. Multiple reaction monitoring (MRM) was used to monitor the transition of the deprotonated molecule m/z of 457 [M - H]- to the product ion 169 for EGCG and the m/z of 187 to 164 for the internal standard. The limit of quantification (LOQ) of EGCG in rat plasma was determined to be 5 ng/mL, and the linear range was 5-5000 ng/mL. The protein binding of EGCG in rat plasma was 92.4 +/- 2.5%. The brain distribution result indicated that EGCG may potentially penetrate through the blood-brain barrier at a lower rate. The disposition of EGCG in the rat blood was fitted well by the two-compartmental model after intravenous administration (10 mg/kg, iv). The elimination half-life of EGCG was 62 +/- 11 and 48 +/- 13 min for intravenous (10 mg/kg) and oral (100 mg/kg) administration, respectively. The pharmacokinetic data indicate that the oral bioavailability of EGCG in a conscious and freely moving rat was about 4.95%.     

Induction of autophagy and apoptosis by the extract of Solanum nigrum Linn in HepG2 cells

Solanum nigrum L. (SN) has been used in traditional folk medicine to treat different cancers. It is also used as a hepatoprotective and anti-inflammatory agent. In this study, we demonstrated that the extract of SN (SNE) induced a strong cytotoxic effect toward HepG2 cells but much less to Chang liver and WRL-68 cells. The mechanisms of the cytotoxic effect were concentration-dependent. High doses of SNE (2 and 5 mg/mL) induced apoptotic cell death in HepG2 cells, as evidenced by increases in the expressions of p-JNK and Bax, mitochodrial release of cytochrome c, and caspase activation. On the other hand, cells treated with low concentrations of SNE (50-1000 microg/mL) revealed morphological and ultrastructural changes of autophagocytic death under electron microscopic observation. Furthermore, these cells showed increased levels of autophagic vacuoles and LC3-I and LC3-II proteins, specific markers of autophagy. The levels of Bcl-2 and Akt that have been implicated in the down-regulation of autophagy were decreased upon SNE treatment. Taken together, these findings indicate that SNE induced cell death in hepatoma cells via two distinct antineoplastic activities of SNE, the ability to induce apoptosis and autophagocytosis, therefore suggesting that it may provide leverage to treat liver cancer.     

Effect of lipopolysaccharide on intranasal administration of liposomal Newcastle disease virus vaccine to SPF chickens

In order to potentiate the low immunogenicity of the inactivated Newcastle disease virus immunized into chickens by mucosal route, liposomes as a drug delivery system and LPS (lipopolysaccharide) as an immuno-stimulator were evaluated. Here, we report a new nasal delivery system of inactivated Newcastle disease virus (NDV) vaccine. The intranasal vaccine was based on different lipids to form MLV (multi-lamellar vehicles) liposomes. The liposomes had combined carrier and adjuvant activities, which induced strong systemic (serum) and local (lung and nasal) humoral responses in SPF (specific-pathogen-free) chickens, and provided protective immunity. PC-Lip (phosphatidylcholine-liposome) elicited significant mucosal secretary immunoglobulin A (s-IgA) levels (p < 0.05) in tracheal lavage fluid and serum IgG levels (p < 0.05). In response to virulent viral challenge, birds treated with PBS (phosphate buffered saline) as control group died, whereas 80% of chickens which received PC-Lip, PC-Lip-LPS, PS-Lip (phosphatidylserine-liposome), and PS-Lip-LPS survived. HAI titers were 1:2560 in the PS-Lip-LPS group and 1:1280 in the PC-Lip, PC-Lip-LPS, and PS-Lip groups after two vaccinations. The results suggest that PC-Lip or PS-Lip might thus be suitable as a potential adjuvant for mucosal vaccination against NDV in chickens.     

Yeast-expressed classical swine fever virus glycoprotein E2 induces a protective immune response

Classical swine fever (CSF) is an economically important swine disease worldwide. The glycoprotein E2 of classical swine fever virus (CSFV) is a viral antigen that can induce a protective immune response against CSF. A recombinant E2 protein was constructed using the yeast Pichia pastoris expression system and evaluated for its vaccine efficacy. The yeast-expressed E2 (yE2) was shown to have N-linked glycosylation and to form homodimer molecules. Four 6-week-old specified-pathogen-free (SPF) piglets were intramuscularly immunized with yE2 twice at 3-week intervals. All yE2-vaccinated pigs could mount an anamnestic response after booster vaccination with neutralizing antibody titers ranging from 1:96 to 1:768. Neutralizing antibody titers at 10 weeks post booster vaccination ranged from 1:16 to 1:64. At this time, the pigs were subjected to challenge infection with a dose of 1 × 10⁵ TCID₅₀ (50% tissue culture infective dose) virulent CSFV strain. At 1 week post challenge infection, all of the yE2-immunized pigs were alive and without symptoms or signs of CSF. Neutralizing antibody titers at this time ranged from 1:4,800 to 1:12,800 and even to 1:51,200 one week later. In contrast, the control pigs continuously exhibited signs of CSF and had to be euthanized because of severe clinical symptoms at 6 days post challenge infection. All of the yE2-vaccinated pigs were E^rns antibody negative and had seroconverted against E^rns by post challenge day 11, suggesting that yE2 is a potential DIVA (differentiating infected from vaccinated animals) vaccine. The yeast-expressed E2 protein retains correct immunogenicity and is able to induce a protective immune response against CSFV infection.     

Cerebral arteriosclerosis in an aged captive polar bear (Ursus maritimus).

Cerebral arteriosclerosis was observed upon necropsy of a 36-yr-old female captive polar bear (Ursus maritimus) that developed a sudden onset of seizure-like activity and died. The medium and large cerebral arteries of the meninges had moderate to severe diffuse discoloration and mineralization of the matrix of the tunica media, with little or no associated cellular reaction. Scanning electron microscopy of the affected arteries showed discrete crystalline calcified deposits in the media and sclerosis of the arterial wall. There were no lesions in the brainstem. The findings suggested a sudden and rapidly fatal loss of blood flow to the brain caused by long-standing arterial lesions. Incidental findings included numerous 0.1- to 10-cm-diameter, hepatic cysts lined with hyperplastic biliary epithelium, a unilateral, unipolar, 3-cm-diameter renal tubular adenoma, and approximately 250 active Baylisascaris sp. nematodes in the intestines.     

Anti-inflammatory potential of flavonoid contents from dried fruit of Crataegus pinnatifida in vitro and in vivo

The dried fruits of Crataegus pinnatifida, a local soft drink material and medical herb, demonstrated antioxidant effect in a previous study. The present study investigates the anti-inflammatory potential of flavonoid contents from dried fruit of C. pinnatifida (CF-Fs). The preliminary investigation showed that CF-Fs (0.25-0.75 mg/mL) decreased the release of PGE2 and nitric oxide as induced by lipopolysaccharide (LPS, an endotoxin) in macrophage RAW 264.7 cells. The in vivo assay showed that pretreatment of rats with CF-Fs (50-200 mg/kg dosed by gavage) for 5 days significantly decreased the serum levels of the hepatic enzyme markers alanine aminotransferase and aspartate aminotransferase induced by the 6-h treatment with LPS (i.p.; 5 mg/kg). Histopathological evaluation of the rat livers revealed that CF-Fs reduced the incidence of liver lesions such as neutrophil infiltration and necrosis induced by LPS. Furthermore, it was found that pretreatment with CF-Fs decreased the hepatic expression of iNOS and COX-2 induced by LPS in rats. These results demonstrate that CF-Fs present anti-inflammatory potential in vitro and in vivo and that they may play a role in hepatoprotection.     

Simultaneous quantification of glyphosate, glufosinate, and their major metabolites in rice and soybean sprouts by gas chromatography with pulsed flame photometric detector

Procedures were developed for the simultaneous determination of glyphosate [N-(phosphonomethyl)glycine] and glufosinate [dl-homoalanin-4-yl-(methyl)phosphinic acid] and their major metabolites, aminomethylphosphonic acid (AMPA) and 3-(methylphosphinico)propionic acid (3-MPPA), in rice and soybean sprouts by gas chromatography (GC) equipped with a pulsed flame photometric detector (PFPD). Herbicides and their major metabolites were previously derivatized with TMOA (trimethyl orthoacetate (TMOA) in the presence of acetic acid, and their GC responses versus heating temperature (70-90 degrees C) and heating time (30-120 min) were optimized. It was found that increases in heating temperature and heating time were unfavorable for the derivatization of glyphosate or glufosinate, whereas high temperature and extended reaction time remarkably facilitated that of AMPA and 3-MPPA except at 90 degrees C for an extended reaction time (120 min). Combination of AG1-X8 anion-exchange chromatography with a Florisil cartridge cleanup process was favorable for the GC-PFPD analysis. Four types of derivatives spiked in rice and soybean sprout matrices were eluted, reaching a baseline separation, in a sequence of 3-MPPA, AMPA, glyphosate, and glufosinate within 14 min using a DB-608 capillary column. Recoveries of glyphosate, AMPA, glufosinate, and 3-MPPA (0.5 ppm) spiked in both sample matrices were determined to be 72-81, 71-86, 101-119, and 83-90%, respectively, whereas the coefficient of variation was determined to be <10% in three repeated determinations. The instrumental limits of detection for glyphosate, AMPA, glufosinate, and 3-MPPA in sample matrices were 0.02, 0.03, 0.02, and 0.01 ppm, respectively. The limits of quantification for glyphosate, AMPA, glufosinate, and 3-MPPA in sample matrices were 0.06, 0.10, 0.06, and 0.04 ppm, respectively.     

螺旋藻属(Spirulina(Arthrospira))一新种(英文)

该文论述了螺旋藻属一新种 .该新种采集于内蒙古伊克昭盟毛乌素沙地巴彦淖尔湖 .通过光学显微镜、扫描和透射电子显微镜照片 ,描述了这一新种的形态特征 ,定名为巴彦淖尔螺旋藻 (Spirulina(Arthrospira)bayannurensisB .Sh .LietC .Qiaosp .nov .) .巴彦淖尔螺旋藻的模式标本存放在内蒙古农业大学植物标本室