Search

The experiment was conducted to investigate the protective effect of Smilax glabra Roxb. aqueous extract on carbon tetrachloride induced acute liver injury in rats by regulating the nucleotide binding leucine rich repeat receptors family pyrin domain containing 3 inflammasome. In this study, a rat acute liver injury model was established by a single intraperitoneal injection of 50 % carbon tetrachloride oil solution (1 ml/kg body weight). A total of 50 rats were randomly divided into control group, model group and 3 Smilax glabra Roxb. aqueous extract intervention groups (0.75, 1.5 and 3 g/kg body weight/d). Smilax glabra Roxb. aqueous extract or distilled water was orally administered by gavage once daily for seven consecutive days. Then the blood and liver samples were collected. The results showed that in the 3 intervention Smilax glabra Roxb. aqueous extract groups, the levels of serum aspartate aminotransferase and Alanine aminotransferase, the content of malondialdehyde in rat liver tissues significantly reduced and superoxide dismutase, catalase and glutathione increased significantly, the liver lobule structures were repaired and the liver cells were aligned in an orderly manner, the expressions of nucleotide binding leucine rich repeat receptors family pyrin domain containing 3 inflammasome, apoptosis associated speck like protein containing and caspase-1 proteins, Interleukin 1 beta messenger ribonucleic acid was decreased. Smilax glabra Roxb. aqueous extract exerted a protective effect against carbon tetrachloride induced acute liver injury by inhibiting the activation of nucleotide binding leucine rich repeat receptors family pyrin domain containing 3 inflammasome, which suggest a promising avenue for the exploration of Smilax glabra Roxb. aqueous extract in improving acute liver injury.

99m Tc with a 6 hour half-life is one of the most important medical isotopes used for the Single-Photon Emission Computed Tomography (SPECT) inspection in hospitals of US, Canada, Europe and Japan. 99m Tc isotopes are extracted by the milking method from parent 99Mo isotopes with a 66 hour half-life. The supply of 99Mo isotopes now encounters a serious crisis. Hospitals may not suitably receive 99Mo medical isotopes in near future, due to difficulties in production by research nuclear reactors. Many countries are now looking for alternative ways to generate 99Mo isotopes other than those with research reactors. We discuss a sustained availability of 99m Tc isotopes via the nat Mo(γ, n) photonuclear reaction, and discuss to solve technical problems for extracting pure 99m Tc isotopes from other output materials of photonuclear reactions.

The goal of this study was to determine the effect of celecoxib, a selective COX-2 inhibitor, on the growth inhibition of osteosarcoma and its potential anticancer mechanisms.Human osteosarcoma cell line MG-63 was used as a model. The inhibitory effect of celecoxib on cell proliferation was assessed by MTT assay. Flow cytometric analysis was used to detect the effects of celecoxib on cell cycle and apoptosis. Western blot analysis was used to detect the protein expression of RECK, matrix metalloproteinase (MMP)-2 and MMP-9 in celecoxib-treated MG-63 cells.MTT assays showed that at a range of concentrations (0-80 µg/ml), celecoxib significantly inhibited the MG-63 cell proliferation in a time- and concentration-dependent manner. The half maximal inhibitory concentration (IC50) of celecoxib was 47.5 µg/ml for 24 h-treatment and 19.2 µg/ml for 48 h-treatment. Flow cytometric analysis demonstrated that treatment with 20 µg/ml celecoxib led to a significant cell cycle arrest at S-phase and an enhancement of apoptosis induction in MG-63 cells at 24 or 48h. Moreover, compared with 24 h-treatment, 48 h-treatment induced more S-phase arrest and apoptosis in MG-63 cells. Western blot analyses revealed that the expression of MMP-2 and MMP-9 was markedly down-regulated but RECK, an inhibitor of MMPs, was markedly up-regulated in MG-63 cells exposed to 20 µg/ml celecoxib for 24 or 48h. Furthermore, the effects of celecoxib on the expression of these molecules were more evident with the increase of treatment time.Celecoxib inhibits the MG-63 cells proliferation through S-phase arrest and apoptosis induction. Celecoxib-induced down-regulation of MMP-2 and MMP-9 and up-regulation of RECK may contribute to the apoptosis induction and an alteration in local tumor microenvironment. These findings suggest that celecoxib may exert at least in part of its anticancer effects via up-regulation of RECK to inhibit the expression of MMP-2 and MMP-9.

The environmental chemistry, fate, and toxicology of the herbicide, linuron, is reviewed. Linuron is a phenylurea herbicide used for selective control of annual weeds in fruit and field crops and noncrop areas. Linuron is soluble in water which suggests that it may leach readily through soils. Its log Koc for soil is 2.83, which indicates a moderate adsorption potential and a moderate mobility. Its half-life is less than 4 weeks in water and approximately 2 months in soil. The primary mode of degradation is microbial. In regions of intensive agriculture, linuron concentrations up to 1100 and 2800 μg L−1 have been detected in Canadian surface waters and ground waters, respectively. Duckweed (Lemna minor), the most sensitive freshwater species for which data were available, had a 5-d lowest-observed-effect level of 70 μg L−1 for growth inhibition. The most sensitive crop species was the tomato (Lycopersicum esculentum) with a LOEAR of 0.018 kg ha−1 for reduced fresh weight. Canadian Water Quality Guidelines (CWQG) specify levels of contaminants that should not be exceeded in order to protect and sustain the major beneficial uses of water in Canada. For linuron, sufficient toxicity data were available to derive an interim CWQG of 7 μg L−1 for the protection of freshwater life, a full CWQG of 0.071 μg L−1 for irrigation water to protect cereals, tame hays, and pasture, and an interim CWQG of 3.3 μg L−1 for irrigation water to protect other crops. © 1998 John Wiley & Sons, Inc. Environ Toxicol Water Qual 13: 1–41, 1998

A review of the environmental chemistry, fate, and toxicology of the nonsystemic fungicide chlorothalonil was conducted. It is used extensively in the eastern Canadian provinces, and it has occasionally been detected in surface and groundwater. In freshwater, chlorothalonil residues can usually be found in biota. Its half‐life in a water/sediment system was found to be

A review of the environmental chemistry, fate, and toxicology of the herbicide MCPA was conducted. MCPA is used worldwide and is among the top ten herbicides sold in Canada. It has a systemic effect and is used to control a large range of broadleaf weeds in agricultural and noncrop lands. MCPA is highly water soluble and has a low affinity for most soil types, which gives it the potential to leach and contaminate groundwaters. It can undergo microbial degradation in aerobic conditions; therefore, it is only slightly persistent in soil and water. In Canada, MCPA has been detected in surface waters at levels varying between 0.00003 and 0.013 mg/l, and at relatively high levels in some groundwater (1.0 mg/1). It has also been reported to affect organisms such as the diatom Navicula pelliculosa at levels as low as of 0.026 mg/1, and the beagle dog at concentrations of 0.75 mg/kg/d. This review includes the development of the Canadian Water Quality Guidelines for MCPA, which are numerical concentratio...

Based on the non-relativistic theory and dipole approximation, we have developed a new program to study the interaction between a circularly polarized laser and hydrogen atoms. In this paper, we present our calculation of above-threshold ionization (ATI) rate based on the new code and compare the results with that of a pertubation theory calculation. The comparison shows that our non-perturbative calculations can produce ATI peak suppression.

Literature on the environmental fate and effects of the benzoic acid herbicide dicamba was reviewed to provide a scientific basis to derive Canadian Water Quality Guidelines. Included in the review was information on the uses and production of dicamba, its physical and chemical properties, environmental monitoring data in Canadian surface water and groundwater, soils, sediments, and biota, and its environmental degradation, persistence, and fate. Through monitoring, dicamba has been detected in less than 8% of surface-water samples to a maximum concentration of 13 micrograms.L-1, while 2% of groundwater samples were positive up to 517 micrograms.L-1. Only one study that analyzed sediments (with no detections) and no field studies that investigated residues in biota were found. Microbial degradation is the most important process governing the dissipation of dicamba in aquatic and soil environments. Photolysis, hydrolysis, volatilization, adsorption to sediment, and bioconcentration are not expected to be significant removal processes, based on limited environmental fate data. The half-life of dicamba in water is 100 mg.L-1. No chronic data were found for either of these groups. The chronic EC50 to 14 freshwater algae, based on growth inhibition, ranged from 100 to > 10,000 micrograms.L-1. No studies on freshwater macrophytes or any marine organisms were found. Agricultural crops exhibited varying toxicity.(ABSTRACT TRUNCATED AT 400 WORDS)