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As a novel formulation of enrofloxacin, the toxicity of enrofloxacin microemulsion was unknown. The present study was conducted to determine the median lethal dose (LD50) of enrofloxacin microemulsion by using the acute toxicity test in mice. Based on the dose range of the pretest, mice in the group receiving the enrofloxacin microemulsion were intragastrically administered the dose levels of 1320.0, 1056.0, 844.8, 675.84, 540.67 and 432.6 mg/kg of body weight, respectively. LD50 calculated by Bliss method was 740.08 mg/kg, and 95% confidence limit of LD50 was 647.11~844.87 mg/kg, which indicated enrofloxacin microemulsion could be labeled as the hazard category 4 according to GHS and be considered as a low toxicity drug. [ABSTRACT FROM AUTHOR]

Background RhoC is a small G protein/GTPase and involved in tumor mobility, invasion and metastasis. Previously, up-regulated RhoC expression is found to play an important role in ovarian carcinogenesis and subsequent progression by modulating proliferation, apoptosis, migration and invasion. Methods We transfected RhoC-expressing plasmid and RhoC siRNA into CAOV3 and OVCAR3 cells respectively. These cells and transfectants were exposed to vascular epithelial growth factor (VEGF), transforming growth factor (TGF)-β1 or their receptor inhibitors with the phenotypes and their related-molecules examined. Results TGF-β1R or VEGFR inhibitor suppressed the proliferation, migration, invasion and lamellipodia formation, the expression of N-cadherin, a-SMA, snail and Notch1 mRNA or protein, and enhanced E-cadherin mRNA and protein expression in CAOV3 and its RhoC- overexpressing transfectants, whereas both growth factors had the opposite effects in OVCAR3 cells and their RhoC-hypoexpressing transfectants. Ectopic RhoC expression enhanced migration, invasion, lamellipodia formation and the alteration in epithelial to mesenchymal transition (EMT) markers of CAOV3 cells regardless of the treatment of VEGFR or TGF-β1R inhibitor, whereas RhoC knockdown resulted in the converse in OVCAR3 cells even with the exposure to VEGF or TGF-β1. Conclusion RhoC expression might be involved in EMT of ovarian epithelial carcinoma cells, stimulated by TGF-β1 and VEGF. [ABSTRACT FROM AUTHOR]

The article focuses on a study regarding the development of residue detection and withdrawal of amoxicillin and levofloxacin hydrochloride nanoemulsion (AMX-LH-NE) in milk from cows suffering with mastitis disease. It mentions that two different high performance liquid chromatography (HPLC) analytical methods were established. The study reveals that lactation period is the suitable time for the elimination of AMX-LH-NE.

The article discusses a study that examined the age and growth of Oxygymnocypris stewartii in the Yarlung Tsangpo River in Tibet to better understand its biology and its relationship with management considerations. Sectioned otoliths of 712 specimens were gathered from August 2008 to August 2009. It was indicated that an annulus forms once a year from March to June. It was shown that females grew more slowly than males but attained a larger size. The use of knowledge of the species' slow growth and long life characteristics to establish reasonable management practices for its conservation is also addressed.

excessive iodine intake is associated with a decrease of the activities of selenocysteine-containing enzymes, supplemental selenium was hypothesized to alleviate the toxic effects of excessive iodine. In order to verify this hypothesis, Balb/C mice were tested by giving tap water with or without potassium iodate and/or sodium selenite for 16 weeks, and the levels of iodine in urine and thyroid, the hepatic selenium level, the activities of glutathione peroxidase (GSHPx), type 1 deiodinase (D1), and thyroid peroxidase (TPO) were assayed. It had been observed in excessive iodine group that hepatic selenium, the activities of GSHPx, D1, and TPO decreased, while in the groups of 0.2 mg/L, 0.3 mg/L and 0.4 mg/L supplemental selenium, the urinary iodine increased significantly. Compared with the group of excessive iodine intake alone, supplemental selenium groups had higher activities of GSHPx, D1, and TPO. We could draw the conclusion that supplemental selenium could alleviate toxic effect of excessive iodine on thyroid. The optimal dosage of selenium ranges from 0.2 to 0.3 mg/L which can protect against thyroid hormone dysfunction induced by excessive iodine intake. [ABSTRACT FROM AUTHOR]

This article discusses a study on the age and growth of a long-lived fish schizothorax o'connori in the Yarlung Tsangpo River in Tibet, China. The study sought to compare parameters of fitted von Bertalanfanffy growth equations with those gathered by other research. The study classified specimens as male, female, or undetermined through the examination of gonads. It found that otoliths grew in sizes with standard length, but growth became asymmetrical over time. It also showed a slower growth rate in female than males.

With the global improvement of iodine nutrition, iodine excess is emerging as a new concern. The aim of this study is to illustrate the physiological effects and potential molecular mechanisms of excessive iodine intake on lipid metabolism. Balb/c mice were given drinking water containing different levels of iodine for 1 month and treated with 1.2 μg/mL iodine for different periods of time, respectively. Plasma lipid parameters and serum thyroid hormones were measured. Expressions of hepatic genes were detected by real-time polymerase chain reactions and Western blot. Dose-dependent hypercholesterolemic effects were detected in mice (TC, r = 0.615; p < 0.01). Drinking 1.2 μg/mL iodine water for 1 month had no significant effect on serum lipid metabolism, while prolonged exposure induced an increase of serum cholesterol. Serum thyroid hormones were not affected by iodine throughout the study. At the molecular level, we detected a dose-dependent attenuation of hepatic low density lipoprotein receptor (LDLr) and thyroid hormone receptor β1 (TRβ1) expression in parallel to the change of serum cholesterol. Treatment with 1.2 μg/mL iodine water for 1 month did not affect LDLr and TRβ1 expression, while 3 or 6 months exposure resulted in a decrease of their expression. Present findings demonstrated dose- and time-dependent hypercholesterolemic effects of iodine excess. Furthermore, our data suggests that TRβ1-mediated down regulation of hepatic LDLr gene may play a critical role in iodine excess-induced hypercholesterolemic effects. [ABSTRACT FROM AUTHOR]

A pretreatment-transient reaction product analysis method was applied to study the reactions and average composition of the possible surface intermediate species in selective catalytic reduction with ethylene of NOx over Co-ZSM-5. The reactions of the surface species, formed by the pretreatment of Co-ZSM-5 in a NO/C2H4/O2 mixture at 275°C, with the NO/O2 flow produced much more N2 than that with the individual NO or O2 flow. The similarity of N2/COx/H2O product distribution generated from the above surface species-NO/O2 reactions and that from the normal NO/C2H4/O2 flow reactions implies that the surface species NCaObHc formed in the three-component pretreatment process is very likely the primary intermediate surface species generated during the real flow reactions. The in situ FT-IR (DRIFT) spectroscopy measurements of the surface species support the above conclusion. [ABSTRACT FROM AUTHOR]

The long afterglow phosphors SrAl2O4: Eu, Dy with different iron content have been prepared by nano-alumina coating process. The effect of crystal structure and luminescence properties of the phosphors by iron is investigated by XRD, luminescence spectra and afterglow curve. It is found that its crystal structure has no change, but luminescence properties have been quenched due to the existence of iron. By changing the iron content from 0. 001 mol to 0. 01 mol, the average luminescence intensity is decreased by 50%, which may be due to the Fe3+— O2- energy transfer to infrared site. Simultaneously, the infrared luminescence in strontium aluminates by iron is observed for the first time. [ABSTRACT FROM AUTHOR]

This paper presents a three-dimensional (3D) coupled-mode model using the direct-global-matrix technique as well as Fourier synthesis. This model is a full wave, two-way three-dimensional model, and is therefore capable of providing accurate acoustic field solutions. Because the problem of sound propagation excited by a point source in an ideal wedge with perfectly reflecting boundaries is one of a few three-dimensional problems with analytical solutions, the ideal wedge problem is chosen in this work to validate the presented three-dimensional model. Numerical results show that the field results by analytical solutions and those by the presented model are in excellent agreement, indicating that the presented model can serve as a benchmark model for three-dimensional sound propagation problems involving a planar two-dimensional geometry as well as a point source. [ABSTRACT FROM AUTHOR]

An exact solution based on the wavenumber integration method is proposed and implemented in a numerical model for the acoustic field in a Pekeris waveguide excited by either a point source in cylindrical geometry or a line source in plane geometry. Besides, an unconditionally stable numerical solution is also presented, which entirely resolves the stability problem in previous methods. Generally the branch line integral contributes to the total field only at short ranges, and hence is usually ignored in traditional normal mode models. However, for the special case where a mode lies near the branch cut, the branch line integral can contribute to the total field significantly at all ranges. The wavenumber integration method is well-suited for such problems. Numerical results are also provided, which show that the present model can serve as a benchmark for sound propagation in a Pekeris waveguide. [ABSTRACT FROM AUTHOR]

β2-microglobulin (B2M), the light chain of major histocompatibility complex class I (MHC I) molecules, has been found to impair hippocampal neurogenesis. Based on the crucial role of hippocampal neurogenesis disturbance in the process of depression and anxiety, the aim of the present study is to investigate whether B2M leads to depressive- and anxiety-like behaviors. We found that 6 days after intracerebroventricular injection with B2M (0.3 μg), the immobility times of rats in the tail suspension test and the forced swimming test were increased, the swimming and climbing time in the forced swimming test was decreased, and the latency to feed in the novelty-suppressed feeding test was increased, indicating that B2M induces depressive-like behaviors. In addition, in the elevated plus maze test, B2M-treated rats displayed obvious decline in the number of entries into and the proportion of time spent in the open arm, while the number of total arm entries was no change, which indicated that B2M induces anxiety-like behaviors. Our present findings suggest that target B2M might represent a novel approach for treatment of depression and anxiety.

Thirty-two Wistar rats were divided randomly into four groups of eight with six females and two males in each group. The rats were exposed to high fluoride drinking water (45 mg F− L−1 from 100 mg NaF L−1), low dietary iodine (0.0855 mg kg−1), or both together in order to assess the effects of these three regimens on the thyroid function of the offspring rats. After the animal model was established, the offspring rats were bred and 10-, 20-, 30-, 60-, and 90-d-old rats were used for the experiment. The treatments for the offspring rats were the same as those of their parents. In comparison with control rats, the relative thyroid glands were changed by three regimens, but the mean values of thyroid weight in the experimental groups saw no marked difference. Serum TT3 levels were increased in all stages in the low iodine (LI) group. In the high fluoride (HiF) group, increase in TT3 levels was observed except in 20-d-old rats. Decrease in TT3 at 20- and 90-d and increase in TT3 at 30- and 60-d were found in HiF+LI group. Serum TT4 levels first saw an increase, and then dropped in the LI and HiF+LI group. However, an increase in TT4 was found in the HiF group. The levels of TSH in serum rocketed at d 20, and then dropped in the next stages in experimental groups. The results suggested that thyroid disorder could be induced by high flroride in drinking water, low iodine diet, or both of them. Exposure time to fluoride or low iodine diet was one of the important factors that fluoride can induce the development of thyroid dyfunction.

Long-chain acyl-CoA synthetase (ACSL) family members include five different ACSL isoforms, each encoded by a separate gene and have multiple spliced variants. ACSLs on endoplasmic reticulum and mitochondrial outer membrance catalyze fatty acids with chain lengths from 12 to 20 carbon atoms to form acyl-CoAs, which are lipid metabolic intermediates and involved in fatty acid metabolism, membrane modifications and various physiological processes. Gain- or loss-of-function studies have shown that the expression of individual ACSL isoforms can alter the distribution and amount of intracellular fatty acids. Changes in the types and amounts of fatty acids, in turn, can alter the expression of intracellular ACSLs. ACSL family members affect not only the proliferation of normal cells, but the proliferation of malignant tumor cells. They also regulate cell apoptosis through different signaling pathways and molecular mechanisms. ACSL members have individual functions in fatty acid metabolism in different types of cells depending on substrate preferences, subcellular location and tissue specificity, thus contributing to liver diseases and metabolic diseases, such as fatty liver disease, obesity, atherosclerosis and diabetes. They are also linked to neurological disorders and other diseases. However, the mechanisms are unclear. This review addresses new findings in the classification and properties of ACSLs and the fatty acid metabolism-associated effects of ACSLs in diseases.