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Diatoms are a major phytoplankton group causing extensive blooms in the ocean. However, little is known about the intracellular biological processes occurring during the blooming period. This study compared the protein profiles of field-collected and laboratory-cultured blooming cells of Skeletonema costatum, and identified highly and differentially expressed proteins using the shotgun proteomic approach. A total of 1372 proteins were confidently identified with two or more peptides. Among them, 222 and 311 proteins were unique to the laboratory and field samples respectively. Proteins involved in photosynthesis, translation, nucleosome assembly, carbohydrate and energy metabolism dominated the protein profiles in both samples. However, different features of specific proteins were also found: proteins participated in light harvesting, photosynthetic pigment biosynthesis, photoprotection, cell division and redox homeostasis were highly detected in the field sample, whereas proteins involved in translation, amino acid and protein metabolic processes, and nitrogen and carbon assimilation presented high detection rates in the laboratory sample. ATP synthase cf1 subunit beta and light harvest complex protein were the most abundant protein in the laboratory and field samples respectively. These results indicated that S. costatum had evolved adaptive mechanisms to the changing environment, and integrating field and laboratory proteomic data should provide comprehensive understanding of bloom mechanisms.

There were errors in the two affiliations of the authors of the article. The correct affiliations are, respectively: 1 Department of Endocrine and Vascular Surgery, Taihe Hospital, Hubei University of Medicine, Shiyan, P.R. China 2 Department of Preventive Medicine, Hubei University of Medecine, Shiyan, P. R. China

An all-optical switch is demonstrated. The switch is based on the photon-induced carrier effect and the principle of the total internal reflection (TIR). An asymmetric Y-branch with multimode waveguides is designed and fabricated on GaAlAs/GaAs epitaxial materials. The 805-nm light is used to activate the carrier effects and generate the total-reflection effect at the branch. The device is characterized at the wavelength of 1.31 /spl mu/m. Its extinction ratio is larger than 18.0 dB when the injected optical density is 15/spl times/10/sup 1/ W/mm/sup 2/.

1,2-Benzenedicarboxaldehyde-3,4,5-trihydroxy-6-methyl (flavipin) was found to be antagonistic against nematodes and fungi. Here we demonstrated that flavipin is a potent antioxidant in vitro and in vivo, which has great potential in the therapy for free radical-associated diseases. Therefore, flavipin-producing bio-source was screened from 80 endophytes in Ginkgo biloba. Seven endophytic fungi were able to synthesize antioxidant substances and identified by ITS rDNA sequences. Among them, Chaetomium globosum CDW7 was a remarkable producer of flavipin. The fermentation parameters of CDW7 were then optimized for high flavipin production. Cultured under the optimal condition (25 °C, 100/250 mL flask, 12 discs/flask, 150 rpm, pH 6.5) for 14 days, CDW7 was able to synthesize flavipin at a production of 315.5 mg/L. In addition, flavipin output was positively correlated to antioxidant activities of crude extracts with a correlation coefficient of 0.8235, indicating that flavipin was the major antioxidant component of CDW7's metabolites. These data demonstrated that CDW7 was a highly yielded bio-source of antioxidant flavipin.

To observe the effects of sargentgloryvine stem extracts (SSE) on the hepatoma cell line HepG-2 in vitro and in vivo and determine its mechanisms of action.Cultured HepG-2 cells treated with SSE were analysed by 3-(4,5-Dimethyl-thiazol-2-yl)-2,5-Diphenyltetrazolium bromide and clone formation assay. The cell cycle and apoptosis analysis were conducted by flow cytometric, TdT-Mediated dUTP Nick End Labeling and acridine orange/ethidium bromide staining methods, and protein expression was examined by both reverse transcriptase-polymerase chain reaction and Western blotting. The pathological changes of the tumor cells were observed by haematoxylin and eosin staining. Tumor growth inhibition and side effects were determined in a xenograft mouse model.SSE treatment could not only inhibit HepG-2 cell proliferation in a dose- and time-dependent manner but also induce apoptosis and cell cycle arrest at the S phase. The number of colonies formed by SSE-treated tumor cells was fewer than that of the controls (P0.05). SSE induced caspase-dependent apoptosis accompanied by a significant decrease in Bcl-xl and Mcl-1 and elevation of Bak expression (P0.05). Tumor necrosis factor α in the xenograft tumor tissue and the liver functions of SSE-treated mice showed no significant changes at week 8 compared with the control group (P0.05). Systemic administration of SSE could inhibit the HepG-2 xenograft tumor growth with no obvious toxic side effects on normal tissues.SSE can induce apoptosis of HepG-2 cells in vitro and in vivo through decreasing expression of Bcl-xl and Mcl-1 and increasing expression of Bax.

To explore the relationship between the pathology of depression and glutamate (Glu) in hippocampus, and the effect on gastric mobility.Depression model was established by using the chronic unpredicted mild stress (CUMS). And stereotaxic and intra-hippocampal microinjection were also used in this experiment. Rat emotion and behaviors were observed by the change in body weight, sucrose preference-test, open field-test and forced swimming-test. Intragastric pressure and mobility were recorded with the instrument of Powerlab/8sp.Compared with the control, 21-day CUMS significantly reduced the increase in body weight, rat sucrose preference, locomotor activity and rearing in open field test, while it significantly increased duration of immobility time in forced swimming test. Meanwhile, magnitudes of intragastric pressure and mobility were significantly declined after 21 days CUMS. Microinjection of Glu into hippocampus mimics the behaviors which were produced in CUMS. The down-rang of gastric mobility in the group of Glu injection was smaller than CUMS, but was much larger than the control. Intrahippocampal microinjection of MK-801 attenuated depression-like behaviors induced by stress, weakened stress-induced inhibition of intragastric pressure, and augmented the magnitudes of gastric contraction.Glu and NMDA receptor in hippocampus are to do much with the etiology of stress- induced depression. They are not only concerned with behavioral changes induced by stress, but also with the variation of gastric activities, nevertheless, differences exist between the effects of behaviors and gastric activities.

The authors have found that by virtue of utilizing the interaction of strongly chemically adsorbed SnCl2 with the analytes of organic/biologic molecules, the authors can not only effectively eliminate the laser carbonization and oxidation of probe molecules (e. g. pyridine), but also obtain specially enhanced Raman signals (e. g. vitamin B6). This method is applicable to the SERS spectroscopic analysis of highly reactive organic/biologic molecules. In the present paper, the authors report the investigation results on the electrochemical SERS spectra of L-carnosine (LCar) for the first time, mainly concentrating on the influence of adsorbed SnCl2 and applied potential on the SERS spectra of LCar. The SERS spectra of LCar were badly interfered by laser carbonization in the absence of SnCl2. However, in the presence of SnCl2 high quality SERS spectra of LCar could be obtained free of carbonization. It is demonstrated that LCar can be immobilized on the gold substrate indirectly via surface coordination with the pre-adsorbed SnCl2 under potential control. Apparently, such a sandwich-like adsorption configuration as Au-Sn(II)-LCar is beneficial both to sensing the strong electromagnetic field at the nanostructured gold surface and to preventing the LCar from damage by the laser.

To investigate the inhibitory effect of artesunate on human endometrial carcinoma RL95-2 cell line proliferation in vitro and the possible mechanisms.The inhibitory effect of artesunate on the cell proliferation was assessed with MTT assay. Transmission electron miscrosopy was used to observe the morphological change of the cells after the treatment. Flow cytometry was performed to examine the changes in the cell cycle, reactive oxygen species (ROS) levels (with DCFH-DA labeling) and mitochondrial membrane potential (rhodamine123 staining), and caspase-3 activity was detected by immunohistochemistry.Artesunate inhibited the proliferation of RL95-2 cells with an IC(50) of 26.29 microg/ml. Transmission electron microscopy revealed early apoptotic changes of the cells with obvious chromatin fragmentation. The cell cycle arrest at G(0)/G(1) phase was observed by flow cytometry, and immunohistochemistry demonstrated caspase-3 positivity in cytoplasm. ROS generation in the cells increased obviously after treatment with artesunate for 72 h, which also resulted in lowered mitochondrial membrane potential.Artesunate suppressed the proliferation of RL95-2 cells in vitro possibly by inducing cell apoptosis.

To investigate the expression and significance of peroxisome proliferators-activated receptor gamma (PPAR gamma) in human glioma.Immunohistochemical staining for PPAR gamma was performed using biopsy specimens of human glioma of various histological types. Expression of PPAR gamma and GFAP in glioma cell lines SWO-38, U251 and SHG-44 were analyzed using Western blotting and reverse transcription-polymerase chain reaction (RT-PCR).Immunohistochemical study showed that PPAR gamma was expressed in glioma tissues with positive rate of 37.5%. Western blotting and RT-PCR showed that PPAR gamma was expressed in both glioma cell lines SWO-38 and U251, but not in SHG-44 cells. However, high expression of GFAP was detected in SHG-44 cells.PPAR gamma is associated with carcinogens of glioma. Actived PPAR gamma by agonist may be a novel approach to the treatment of glioma.

To observe the effects of exogenous human chorionic gonadotropin (hCG) on nude mice bearing transplanted endometrial carcinoma.Human endometrial carcinoma xenograft was transplanted in nude mice, and the effects of hCG injection on the tumor growth was evaluated according to tumorigenesis and xenograft weights. The expression of Ki-67 in the tumor was determined by immunohistochemistry, and HE staining was performed for morphological observation and measurement of the necrosis area in the tumor. The effect of hCG on fibrosis in the tumor was evaluated with Masson staining.Compared to normal saline-treated tumor-bearing mice, the mice with hCG treatment showed increased tumor weight. HE staining for tumors in HCG-treatment group visualized tumor cell arrangement in glandular structure with smaller necrosis area, and Masson staining identified thick and compact collagen fibers as compared with the thin and loosely arranged fibers in saline-treated group. No significant difference was found in the Ki-67 expression in the tumors between the two groups.Exogenous hCG can promote the differentiation of the endometrial carcinoma cells in vivo.

To screen and identify differentially expressed genes between a fertile patient and another infertile patient who belonged to a large Chinese pedigree affected with androgen insensitivity syndrome (AIS).We constructed the forward and reversed subtracted libraries using genital skin fibroblasts (GSF), which were obtained from the fertile patient MJ and infertile patient ZGJ, as tester respectively. Candidate clones were screened with colony in situ hybridization, dot blot, and Southern blot analysis step by step and conformed with Northern blot analysis. The potential positive clones were sequenced and the homology of the sequences was analyzed.The forward and reversed subtracted libraries containing differentially expressed pattern of two GSF cell lines were constructed. Two positive clones identified by Northern blot were obtained in the reversed subtracted library. Eleven candidate clones from the two libraries that failed to hybridize with both RNA populations were obtained simultaneously, which might represent differentially expressed low abundance transcripts. Sequencing results and homology analysis demonstrated that the two positive clones were significantly homologous with the genes of autotaxin-t and calcium binding protein calcyclin (S100A6), respectively.Two positive clones and eleven clones showing no hybridization signals may represent differentially expressed genes between the two GSFs. This finding may be useful to elucidate the molecular mechanisms leading to phenotypic variation and preserved fertility of the AIS pedigree.

Static experiments were performed to investigate the adsorption characteristics of ammonium by suspended mineral matters (SPM). Three kinds of suspended mineral matters including montmorillonite, kaolin and the particles separated from the sediments of the Taihu Lake were used as the sorbent. The experiments show that the equation could be gotten within 30 min, and that the ammonium adsorption on mineral particles conformed to Herry isotherm. The parting coefficient of the adsorption about ammonium could reach 548.30, 287.36, 191.27 L/kg in experimental condition that there were 1 000 mg/L mineral particles and 1.0 mg/L ammonium in water with pH 7.00. Some effectors such as temperature, pH and salinity of the water on the adsorption about ammonium were observed. The results show that the quantity of adsorbed ammonium slightly decrease with the increasing of temperature and salinity, and greatly do with increasing of pH. The quantity decrease rapidly also with the increasing of the content of mineral particles below 1 000 mg/L.

The Mach-Zehnder Interferometer traveling-wave modulator designed by method of lines is fabricated on the substrate of semi-insulator GaAs, adopting the asymmetric multiple quantum wells with larger change of field-induced reflective index. In order to reduce the microwave loss by the unnecessary carriers, ridge waveguide is used and a mesa is wet etched. Then the microwave frequency response are measured and analyzed. It shows that the frequency response drops faster at lower frequency, and keeps no evident drop in the range of 2.5/spl sim/20 GHz which means the bandwidth of 20 GHz, and even larger for the limitation of measurement. Nevertheless, the microwave loss is relatively large. Finally, the reason is argued and the improving ways are proposed.