Calculated plasma medial effective concentration of propofol with and without magnesium sulfate at loss of consciousness

Background Perioperative disorder of magnesium, an important cation in the human body, may affect clinical anesthesia. The pharmacological data of propofol use, which is popularly used in the anesthesiology department and intensive care unit, is incomplete in Chinese patients. This study aimed to assess the effect of magnesium sulfate on the calculated plasma medial effective concentration （Cp5Ocal） of propofol at loss of response to command in Chinese females.

Effects of Low Concentrations of Di-(2-ethylhexyl) and Mono-(2-ethylhexyl) Phthalate on Steroidogenesis Pathways and Apoptosis in the Murine Leydig Tumor Cell Line MLTC-1

The aim of this study was to evaluate the effects of low concentrations of DEHP and MEHP on steroidogenesis in a murine Leydig tumor cell line （MLTC-1） in vitro. The result of flow cytometry analysis revealed that the proportion of apoptotic cells was significantly increased after the exposure to DEHP. All three genes （P450scc, P450c17, and 38HSD） under study showed an increased expression following exposure to DEHP or MEHP, although some insignificant inhibitory effects appeared in the 10μmol/L treatment group as compared with the controls. It was also found that DEHP or MEHP stimulated INSL3 mRNA and protein especially in the 0.001 μmol/L treatment group. Testosterone secretions were stimulated after the exposure to DEHP or MEHP. Alterations of steroidogenic enzymes and INSL3 in MLTC-1 cells might be involved in the biphasic effects of DEHP/MEHP on androgen production.

Particle concentration effect in adsorption/desorption of Zn(Ⅱ) on anatase type nano TiO_2

Adsorption/desorption in a new Zn（Ⅱ）-TiO2 adsorption system was investigated at different particle concentrations （Cp）. TEM, SEM and XRD analyses revealed that the TiO2 particles were an aggregation of nano-sized （approximately 10 nm） pure anatase-type TiO2. Adsorption experiments were carried out with particle concentrations of 100, 400 and 1000 mg/L, and their adsorption isotherms were found to decline successively, showing an obvious Cp effect. Desorption experiments indicated that adsorption in this system was irreversible, and the irreversibility increased with increasing Cp. These phenomena could be explained by the MEA （metastable equilibrium adsorption） theory and the Cp effect could be modeled well with an MEA-Freundlich-type Cp effect isotherm equation. This study may heln understand environmental behavior of contaminants on ultrafine natural particles.

Effect of Phosphatization on Element Concentration of Cobalt-Rich Ferromanganese Crusts

A detailed study on a small scale of the effect of phosphatization on the chemistry of marine cobalt-rich ferromanganese crusts supplies useful information for the evaluation and comprehensive utilization of crust mineral resources. Sub-samples from top to bottom of a 10-cm thick sample from the NW Pacific Magellan seamount were taken at 5 mm intervals. The concentration profiles of ore-forming and rare earth elements show that obvious differences exist between young unphosphatized crusts and old phosphatized crusts. In the old crusts Fe, Mn, Si, Al, Zn, Mg, Co, Ni and Cu elements are depleted and Ca, P, Sr, Ba and Pb elements are enriched. The order of depletion is Co > Ni > Mg > Al > Mn > Si> Cu > Zn > Fe, while the order of enrichment is P > Ca > Ba > Pb > Sr. The phosphate mineral controls the concentration variation of the ore-forming elements in crusts and causes loss of the main ore-forming elements such as Co and Ni. The phosphatization also affects the abundance of REEs in the crusts. REEs are more abundant and the content of Ce in old crusts is higher than that in young crusts, however, the pattern of REEs and their fractionation characteristics in new and old crusts are not fundamentally changed. A Y-positive anomaly in old crusts has no relationship to the phosphatization.

Effect of Oxygen Concentration and Annealing Theatment on the Optical Properties of the Transparent Conductive CdIn_2O_4 Thin Films

Transparent conductive cadmium indium oxide films (CdIn2O4) were prepared by r.f. reactive sputtering from Cd-In alloy targets under an Ar-O2 atmosphere. Electrical conductivity of the order of 105Ω-1.m-1 and the optical transmission as high as 94% are easily attained by postdeposition annealing treatment. The effects of oxygen concentration in the reactive gas mixture and post-deposition annealing treatment on the optical transmittance as well as optical parameters, such as refractive index (n), extinction coefficient (k), real part (ε') and imaginary part (ε') of the dielectric constant, were studied in the visible and near-infrared region. The highfrequency dielectric constant ε∞ the plasma frequency ωP, and the conduction band effective mass mc of different samples were also investigated

Effect of Abrasive Concentration on Chemical Mechanical Polishing of Sapphire

Effects of abrasive concentration on material removal rate CMRR） and surtace quality m the chemical mecnamcal polishing （CMP） of light-emitting diode sapphire substrates are investigated. Experimental results show that the MRR increases linearly with the abrasive concentration, while the rms roughness decreases with the increasing abrasive concentration. In addition, the in situ coefficient of friction （COF） is also conducted during the sapphire polishing process. The results present that COF increases sharply with the abrasive concentration up to 20 wt% and then shows a slight decrease from 20wt% to 40wt%. Temperature is a product of the friction force that is proportional to COF, which is an indicator for the mechanism of the sapphire CMP.

Combined effects of temperature and copper ion concentration on the superoxide dismutase activity in Crassostrea ariakensis

Superoxide dismutase（SOD） is a crucial antioxidant enzyme playing the first defense line in antioxidant pathways against reactive oxygen species in various organisms including marine invertebrates. There exist mainly two specific forms, Cu/Zn-SOD（SOD1） and Mn-SOD（SOD2）, in eukaryotes. SODs are known to be concurrently modulated by a variety of environmental stressors. By using central composite experimental design and response surface method, the joint effects of water temperature（18–34°C） and copper ion concentration（0.1–1.5 mg/L） on the total SOD activity in the digestive gland of Crassostrea ariakensis were studied. The results showed that the linear effect of temperature was highly significant（P〈0.01）, the quadratic effect of temperature was significant（P〈0.05）; the linear effect of copper ion concentration was not significant（P〉0.05）, while the quadratic effect of copper ion concentration was highly significant（P〈0.01）; the interactive effect of temperature and copper ion concentration was not significant（P〉0.05）; the effect of temperature was greater than that of copper ion concentration. The model equation of digestive gland SOD enzyme activity towards the two factors of interest was established, with R2 and predictive R2 as high as 0.961 6 and 0.820 7, respectively, suggesting that the goodness-offit to experimental data be very satisfactory, and could be applied to prediction of digestive gland SOD activity in C. ariakensis under the conditions of the experiment. Our results would be conducive to addressing the health of aquatic animals and/or to detecting environmental problems by taking SOD as a potential bioindicator.

Variation of sulfate aerosol concentrations over the western Pacific and their effect on clouds, radiation and precipitation

Under bilateral cooperation between the United States of America and the People's Republic of China, a series of research cruises were conducted over the western Pacific Ocean. It was found that a) the non-sea-salt sulfate aerosol particles are the major source of cloud condensation nuclei, b) the population of clouds and the total albedo are proportional to the concentration of condensation nuclei and consequently to the concentration of the non-sea-salt aerosol particles, and c) the amount of rainfall is inversely proportional to the concentration of non-sea-salt sulfate aerosol particles. It seems that anthropogenic sulfate aerosol particles affect the regional planetary albedo and climate and that the contribution from biogenically derived sulfate aerosol particles is of lesser importance.

Reduced Life Expectancy Model Analyses of Exposure Time Effects of Endocrine Disruptors to Teleost Fishes Based on Effect Concentration of Hepatic Biomarkers

In this current paper, the exposure time effects on four endocrine disruptors and teleost fishes were evaluated using the reduced life expectancy (RLE) model based on the effect concentration (EC50) of available literature published. The result on the regression analysis over different exposure times has demonstrated that the EC50 of hepatic biomarkers falls with increasing exposure times in a predictable manner. The slopes of the regression equations reflect the strength of the toxic effects on the various teleost fish. The EC50 reduction over time can be interpreted based on the bioconcentration process, which can be used to understand transfer routes of the compounds from water to fish body. RLE model also provides useful information in assessing the toxic effects on fish life expectancy as a result of the occurrence of compounds.

Studies on the Hazardous Effects and the Maximum Allowable Concentration of Pyrophyllite Dust

Pyrophyllite (H2Al2,Si4 O22, ) dust (P-dust) is a mixture of silica (10-40% ), differentproportions of a luminium oxide (Al2O3 ), and various metal compounds. People with occupa-tions known to be associated with exposure to P-dust include miners, other industrial workersand persons engaged in artistic carving. Currently, little is known about pyrophyllite pneumo-coniosis from P-dust. This study was designed to investigate the hazardous effects of P-dustand to suggest a maximum allowable concentration (MAC) of the dust.This.study included four parts: (i) Occupational epidemiology surveys in 781 workersfrom 1 pyrophyllite mine (PM) and four pyrophyllite carving mills (PCM), with a registra-tion rate of 98 %. (ii) In vitro studies: Six groups of rats were expeed to different levels ofP-dust; the cytotoxicity of P-dust on rat alveolar macrophages (AM) was investigated by de-termining the potassium'content of AM and the activity levels of lactate dehydrogenase (LDH)in AM culture fluid. (iii) Mineralogical analysis of P-dust: The contents of silica (SiO2 ), alu-minium (Al), ferrum (Fe), niikel (Ni), zinc (Zn) and copper (Cu) in hath PM-dust andPCMdust were determined. (iv ) Determination of P-dust MAC: Using the life-talbemethod, an investigation of the hygiene standard of P-dust was carried out in 625 workers ex-POSed to either PM-dust or PCM-dust, uPon whom routine radiographs were Performed.The results suggest that the risk of developing pneumoconiosis from pyrophyllite dust issignificantly higher for PM workers than for PCM workers. The prevalence rate of PCM-dustpneumoconiosis is significantly higher in men than in women. The content of SiO2 and AlO3in the mixture of P-dust is the most important factor in the etiology of pyrophyllitosis. De-pending on the different P-dust MAC values, we suggest that 2 rng/m3 and 4 mg/m' shouldbe considered as the MAC for PM-dust and PCM-dust, respectively, and 3 mg/m' fOr P-dust. We believe that establishing different hygiene standards is more accurate even thoughworkers are exposured to the 'same' dust

Effects of leaf N concentration and leaf area index on determining rice tillering

Relative tillering rate(RTR)increased linear-ly with the increasing of leaf N concentration(NLV)has been already reported.To testwhether this relationship could be used toquantitatively explain the difference in tilleringamong a wide range of N application,field ex- periments were conducted at the IRRI farm,Los Banos,Laguna,the Philippines.Two in- dica cultivars,IR 72 and IR68284H wereused.For each cultivar,12 treatments includ- ing 4 N levels(0,60,120,and 180kgN·ha)and 3 transplanting spacing(30×20,20×20,and 10×20cm)were arranged in a ran-domized split-plot design with 4 replications.The N treatments were designated as mainplots and spacings as subplots.Fourteen-day-old seedlings were transplanted with 3seedlings per hill.The subplot area was 20m~2.Nitrogen fertilizer was applied as basal,atmidtillering,and at panicle initiation in threeequal splits.P,K,and Zn were applied asbasal at normal dosage.The field was flooded.Plant samples were taken every 7-14 d from 14d after transplanting to flower

Effect of agar concentration in media on green plantlet regeneration frequency in rice anther culture

We studied the effect of agar concentration inmedia on callus induction rate and green plant-let regeneration frequency in rice.Materialswere Fgeneration of indica/indica or indica/japonica,which were 96E76(Hei’e/Zhaiye- qing 8),96E80[(IR 24/Guanglu＇ai 4//Zhongnan’ai)/Yifengzao],96E86(Zhong- munong 9/Zhaiyeqing 8).The induction mediaused was M8+2mg/L 2,4-D,and agar con-centrations were 0.6％,0.8％,and 1.0％,respectively.Regeneration media was MS+2mg/L KT+0.5mg/L IAA+0.5mg/LNAA,and agar concentrations were 0.6％ and1.0％.Results indicated that the calli induc-

Efficacy and safety of propofol target-controlled infusion combined with butorphanol for sedated colonoscopy

BACKGROUND Propofol is a short-acting,rapid-recovering anesthetic widely used in sedated colonoscopy for the early detection,diagnosis and treatment of colon diseases.However,the use of propofol alone may require high doses to achieve the induction of anesthesia in sedated colonoscopy,which has been associated with anesthesia-related adverse events(AEs),including hypoxemia,sinus bradycardia,and hypotension.Therefore,propofol co-administrated with other anesthetics has been proposed to reduce the required dose of propofol,enhance the efficacy,and improve the satisfaction of patients receiving colonoscopy under sedation.AIM To evaluate the efficacy and safety of propofol target-controlled infusion(TCI)in combination with butorphanol for sedation during colonoscopy.METHODS In this controlled clinical trial,a total of 106 patients,who were scheduled for sedated colonoscopy,were prospectively recruited and assigned into three groups to receive different doses of butorphanol before propofol TCI:Low-dose butorphanol group(5μg/kg,group B1),high-dose butorphanol group(10μg/kg,group B2),and control group(normal saline,group C).Anesthesia was achieved by propofol TCI.The primary outcome was the median effective concentration(EC50)of propofol TCI,which was measured using the up-and-down sequential method.The secondary outcomes included AEs in perianesthesia and recovery characteristics.RESULTS The EC50 of propofol for TCI was 3.03μg/mL[95%confidence interval(CI):2.83-3.23μg/mL]in group B2,3.41μg/mL(95%CI:3.20-3.62μg/mL)in group B1,and 4.05μg/mL(95%CI:3.78-4.34μg/mL)in group C.The amount of propofol necessary for anesthesia was 132 mg[interquartile range(IQR),125-144.75 mg]in group B2 and 142 mg(IQR,135-154 mg)in group B1.Furthermore,the awakening concentration was 1.1μg/mL(IQR,0.9-1.2μg/mL)in group B2 and 1.2μg/mL(IQR,1.025-1.5μg/mL)in group B1.Notably,the propofol TCI plus butorphanol groups(groups B1 and B2)had a lower incidence of anesthesia AEs,when compared to group C.Furthermore,no significant differences were observed in the rates of AEs in perianesthesia,including hypoxemia,sinus bradycardia,hypotension,nausea and vomiting,and vertigo,among group C,group B1 and group B2.CONCLUSION The combined use with butorphanol reduces the EC50 of propofol TCI for anesthesia.The decrease in propofol might contribute to the reduced anesthesia-related AEs in patients undergoing sedated colonoscopy.

Effect of thyroid hormone on serum NO concentration and iNOS activity of intestinal mucosa in septic rats

Objective To investigate the effect of exogenous thyroid hormone on serum NO and iNOS activity of intestinal mucosa in septic rats. Methods Septic model was established by cecal ligation puncture (CLP) in male SD rats. Triiodothyronine ( T3 ) was administered intraperitoneally to correct the low T3 syndrome of septic rats. Blood was collected to examine serum NO and thyroid hormone concentration. Intestinal mucosa iNOS activity was assayed using immunochemical stain. Results Mortality rate in the prevention group was significantly lower than the septic group (Log rank = 3. 85, P 【 0.05). Serum NO concentration was significantly lower in the prevention group (F=19.6,F【0.01). The degree of inflammatory injury of intestinal mucosa was much milder in the prevention group than in the septic group (x2 = 5.303,P【0. 05). Mucosa iNOS activity was also significantly lower in the prevention group (x2 = 4. 876, P【0. 01). Conclusion Thyroid hormone protects the intestinal mucosa barrier inhibiting the expression of

Laboratory culture of the freshwater benthic gastropod Bellamya aeruginosa (Reeve) and its utility as a test species for sediment toxicity

This study aimed to develop original laboratory culture and sediment toxicity testing protocols for the freshwater gastropod Bellamya aeruginosa （Reeve）, a new potential species for sediment toxicity testing. B. aeruginosa was successfully cultured with an effective culture system under proposed laboratory conditions. Optimal ad libitum feeding levels for larvae, juveniles, and adults were 2.0, 6.0, and 16.0 mg fish food/（snall.day）, respectively. Mean survival rates of juveniles were higher than 90%, The snails could be sexed at 9 weeks of age, and their generation time is approximately 4 months. Reproduction continued all year around; the mean fecundity was 0.55 newborn/（female.day）. The utility of this species for bioassays was evaluated in both 10-day and 28-day case studies with artificial sediments. The 10-day LC50 of Cu for larvae was 480 μg/g dry weight （dw）, and the lowest observed effects concentration of Cu for survival and growth of larvae was 195 μg/g dw. Survival and growth are reliable indicators of acute toxicity. Larvae accumulated more Cu than adults. B. aeruginosa exhibited a higher sensitivity to Cu exposure than standard test species （Hyalella azteca and Chironomus tentans）. The 28-day test of sediment toxicity with adults showed that fecundity was a robust endpoint indicator of reproductive toxicity, and the biochemical endpoints of superoxide dismutase, catalase, and glutathione could be used as sensitive biomarkers for Cu-induced oxidative damage. B. aeruginosa can be therefore recommended as a candidate for the standardization of the freshwater sediment toxicity test protocol.

A comparative study of classical and biochemical endpoints for phytotoxicity testing of chlorobenzoic acids

The phytotoxicity of chlorobenzoic acids(CBAs) was studied and the biochemical endpoints' suitability and sensibility was evaluated. Two terrestrial plant species in the same family were exposed to different concentrations of CBAS and tested their germination according to the guideline of Organization for Economic Cooperation and Development(OECP, 1984). The results showed that CBA dose-inhibition rate of classical endpoint had the distinct linear relationship in the range of 10%—50% inhibition rate for root elongation(p<0.01), and the dose variances of CBAs had the greater influence on the inhibition rate of germination than on inhibition rate of root elongation. The CBA dose half effect concentration-inhibition rate of two antioxidant enzyme activity superoxide dismutase(SOD) and catalase (CAT) had the quadratic relationship, and CBA dose-inhibition rate of the peroxides(POD) activity had the linear relationship(p<0.05). Comparing the half effect concentration (EC_ 50) of two kinds of endpoints, the POD activity was more sensitive than classical endpoint, however, SOD and CAT activity were not sensitive in the experiment.

Effect of Rare Earth Elements on Quantity Growth of Crops

The effects of rare earth on the growth of rice, rape and soybean in three kinds of soils were studied with the method supposed by Economic Co-operation and Development organization (OECD), and the EC50(median growth concentration)values were obtained. The inhibition of RE on the growth of rice and rape in red soil and on the growth of soybean in yellow fluvo-aquic soil is higher with stronger poison effects. Compared with other heavy metals such as Hg, Cd, Pb, As, the poison of RE on crops is weaker.

Molecular dynamics simulations of A-DNA in bivalent metal ions salt solution

A-form DNA is one of the biologically active double helical structure.The study of A-DNA structure has an extensive application for developing the field of DNA packaging in biotechnology.In aqueous solution,the A-DNA structure will have a free transformation,the A-DNA structure will be translated into B-form structure with the evolution of time,and eventually stabilized in the B-DNA structure.To explore the stability function of the bivalent metal ions on the A-DNA structure,a series of molecular dynamics simulations have been performed on the A-DNA of sequence(CCCGGCCGGG).The results show that bivalent metal ions(Mg^(2+),Zn^(2+),Ca^(2+))generate a great effect on the structural stability of A-DNA in the environment of high concentration.As the interaction between metal ions and electronegative DNA chains,the stability of A-DNA in solution is gradually improved with the increasing solution concentration of ions.In metal salt solution with high concentration,metal ions can be easily distributed in the solvation shells around the phosphate groups and further lead to the formation of shorter and more compact DNA structure.Also,under the condition of the same concentration and valency of the metal ions,the stability of A-DNA structure is different.The calculations indicate that the structure of A-DNA in CaCl_(2)solution is less stable than in MgCl_(2)and ZnCl_(2)solution.

Effect of AlCl_3 concentration on nanoparticle removal by coagulation

In recent years,engineered nanoparticles,as a new group of contaminants emerging in natural water,have been given more attention AlCl3 In order to understand the behavior of nanoparticles in the conventional water treatment process,three kinds of nanoparticle suspensions,namely multi-walled carbon nanotube-humic acid（MWCNT-HA）,multiwalled carbon nanotube-N,N-dimethylformamide（MWCNT-DMF） and nano TiO2-humic acid（TiO2-HA） were employed to investigate their coagulation removal efficiencies with varying aluminum chloride（AlCl3） concentrations AlCl3 Results showed that nanoparticle removal rate curves had a reverse ＂U＂ shape with increasing concentration of aluminum ion（Al^（3＋） ）AlCl3 More than 90% of nanoparticles could be effectively removed by an appropriate Al^（3＋） concentration AlCl3 At higher Al^（3＋） concentration,nanoparticles would be restabilized AlCl3 The hydrodynamic particle size of nanoparticles was found to be the crucial factor influencing the effective concentration range（ECR） of Al^（3＋） for nanoparticle removal AlCl3 The ECR of Al^（3＋） followed the order MWCNT-DMF 〉 MWCNT-HA 〉 TiO2-HA,which is the reverse of the nanoparticle size trend AlCl3 At a given concentration,smaller nanoparticles carry more surface charges,and thus consume more coagulants for neutralization AlCl3 Therefore,over-saturation occurred at relatively higher Al^（3＋） concentration and a wider ECR was obtained AlCl3 The ECR became broader with increasing p H because of the smaller hydrodynamic particle size of nanoparticles at higher p H values AlCl3 A high ionic strength of Na Cl can also widen the ECR due to its strong potential to compress the electric double layer AlCl3 It was concluded that it is important to adjust the dose of Al^（3＋） in the ECR for nanoparticle removal in water treatment.