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In this paper, the terahertz (THz) and infrared (IR) characteristic absorption spectra of aqueous glucose solutions and aqueous fructose solutions with different concentrations were measured and studied. The absorption spectra of these two molecules in solid-state and in aqueous solutions were compared and analyzed, the significant effect of molecular adjacent environment on the molecular structure and vibrational mode was revealed. In addition, the THz and IR absorption spectra of these two isomers' aqueous solutions were also compared and explored. No obvious differences were found from their IR absorption features measured at room temperature, while their THz absorption spectra do have the differences, indicating THz characteristic absorption spectra more suitable for the detection and identification of aqueous glucose and fructose solutions. The results are helpful to understand the influence of aqueous solutions environment on the molecular structures and vibrational modes of the materials, and also provide a theoretical reference for the quantum chemical calculation of biological macromolecules.

Aim: Proteasome inhibitors have been found to suppress glioma cell proliferation and induce apoptosis, but the mechanisms are not fully elucidated. In this study we investigated the mechanisms underlying the apoptosis induced by the proteasome inhibitor MG-132 in glioma cells., Methods: C6 glioma cells were used. MTT assay was used to analyze cell proliferation. Proteasome activity was assayed using Succinyl-LLVY-AMC, and intracellular ROS level was evaluated with the redox-sensitive dye DCFH-DA. Apoptosis was detected using fluorescence and transmission electron microscopy as well as flow cytometry. The expression of apoptosis-related proteins was investigated using Western blot analysis., Results: MG-132 inhibited C6 glioma cell proliferation in a time- and dose-dependent manner (the IC(50) value at 24 h was 18.5 μmol/L). MG-132 (18.5 μmol/L) suppressed the proteasome activity by about 70% at 3 h. It induced apoptosis via down-regulation of antiapoptotic proteins Bcl-2 and XIAP, up-regulation of pro-apoptotic protein Bax and caspase-3, and production of cleaved C-terminal 85 kDa PARP). It also caused a more than 5-fold increase of reactive oxygen species. Tiron (1 mmol/L) effectively blocked oxidative stress induced by MG-132 (18.5 μmol/L), attenuated proliferation inhibition and apoptosis in C6 glioma cells, and reversed the expression pattern of apoptosis-related proteins., Conclusion: MG-132 induced apoptosis of C6 glioma cells via the oxidative stress.

Antihypertensive efficacy and safety of losartan/hydrochlorothiazide (HCTZ) combinations have not been adequately studied in Asians. In this open-label, 12-week study in seven Asian areas, patients on monotherapy with angiotensin receptor blockers (ARBs) or angiotensin-converting enzyme inhibitors (ACEIs) but not at blood pressure (BP) goal (sitting diastolic BP (SiDBP) <90 mm Hg in non-diabetics and <80 mm Hg in diabetics) were switched to losartan 50 mg/HCTZ 12.5 mg. At 4 and 8 weeks, the therapy for patients not at goal BP was titrated to losartan 100 mg/HCTZ 12.5 mg and to losartan 100 mg/HCTZ 25 mg, respectively. Data analysis included 430 patients with mean (s.d.) age 53.0 (10.1) years and 51.9% of the female gender. After 8 weeks (primary end point; titration up to losartan 100 mg/HCTZ 12.5 mg), 73.5% (95% confidence interval (CI): 69.0-77.6) of patients reached BP goal; 63.4 and 78.1% of patients reached BP goal at 4 weeks (titration up to losartan 50 mg/HCTZ 12.5 mg) and at 12 weeks (titration up to losartan 100 mg/HCTZ 25 mg). The mean changes from baseline (95% CI) in sitting systolic BP and SiDBP at 8 weeks were -16.7 (-18.0 to -15.4) mm Hg and -12.1 (-12.9 to -11.4) mm Hg, respectively. Clinical and laboratory adverse experiences (AEs) were reported in 27.5 and 21.0% of patients, respectively. Nine patients were discontinued because of drug-related clinical AEs. Switching Asian patients currently not at BP goal with ARB or ACEI monotherapy to a losartan/HCTZ combination achieved BP goal in the majority of patients. Losartan/HCTZ combinations were generally well tolerated.

The effects of human EGFR to the malignant phenotype of human breast cancer cell line MDA-MB-231 were investigated experimentally. A retroviral vector containing a 5'1350bp fragment of the human EGFR cDNA in the antisense orientation was transfected into targeted cells by lipofectamine. The effects on cell proliferation, cell cycle and adherent ability to extracellular matrix (ECM) components were studied after the expression of antisense transcripts to EGFR 5'1350bp fragment in target cells. In vitro studies showed that the growth ability of the transfected cells was partially inhibited in comparison to parental cells and to cells transfected with the plasmid containing the neomycin resistance gene only. It was found that EGF (10 ng/ml) had an argumenation effect on the growth of transfected MDA-AS10 cells but not MDA-MB-231 cells. Flow cytometric analysis showed that the cell cycle of the transfected cells was abnormal with a decrease of cells in G2/M and S phases and an increase of cells in G1 phase, indicating a blockage in phase G1. Immunofluorescence of EGFR expression in transfectants stained with an anti-EGFR antibody was decreased and their growth in soft agarose was also severely impaired. The transfected cells showed less adherence to laminin (LN) and fibronectin (FN). In short, EGFR antisense RNA decreases the expression of EGFR on MDA-MB-231 cells and partially reverses their malignant phenotype as well.