Preparation and characterization of an amphipathic magnetic nanosphere

The amphipathic magnetic nanospheres were synthesized using C8 and polyethylene glycol as ligands. Their morphology, structure, and composition were characterized by transmission electron microscope, Fourier transform infrared, and elementary analysis. The prepared materials presented uniform sphere with size distribution about 200 nm. The magnetic characteristics of magnetic nanomaterials were measured by vibrating sample magnetometer. The target products had a saturation magnetization value of 50 emu g(-1) and superparamagnetism. The adsorption capability was also studied by static tests, and the material was applied to enrich benzenesulfonamide from calf serum. The results exhibited that the C8-PEG phase owned better adsorption capability, biocompatible property, and dispersivity in aqueous samples.

Ti4+-immobilized multilayer polysaccharide coated magnetic nanoparticles for highly selective enrichment of phosphopeptides

A novel magnetic polymer nanoparticle (Fe₃O₄@SiO₂@(HA/CS)₁₀–Ti⁴⁺ IMAC) was synthesized for the highly selective and efficient enrichment of phosphopeptides.

Thermally stable gold/alumina aerogel catalysts prepared by a simultaneous synthesis process for solvent-free aerobic benzyl alcohol oxidation

Gold nanoparticles physically trapped in the framework of alumina aerogel exhibit excellent thermal stability and catalytic activity at high temperature.

Galectin-7 in cardiac allografts in mice: increased expression compared with isografts and localization in infiltrating lymphocytes and vascular endothelial cells

We sought to identify elevated expression of galectin-7, a T-cell-binding protein, in renal allograft recipients undergoing acute rejection episodes. Allografts and isografts were examined immunohistologically and using quantitative Western blot analysis for galectin-7 protein. The expression of galectin-7 in T lymphocytes from draining lymph nodes in the recipient mice was examined using flow cytometry. We observed galectin-7 to gradually increase with time in the allografts to be significantly higher than that in isografts at days 3, 5, and 7 postoperative: 0.85 ± 0.03 versus 0.69 ± 0.05; 1.15 ± 0.11 versus 0.81 ± 0.02; and 2.02 ± 0.12 versus 0.81 ± 0.05 (P < .05). The majority of galectin-7 was located in the infiltrating lymphocytes and vascular endothelial cells. Furthermore, the percentage of CD4+galectin-7+ and CD8+galectin-7+ T cells from draining lymph nodes in the allograft group was higher than that in the isograft group: 28.0 ± 1.0% versus 1.2 ± 0.2%; and 12.4 ± 0.8% versus 0.4 ± 0.1% (P < .01). In conclusion, galectin-7 relates to acute allograft rejection and T-cell responses possibly as an accelerant.

Effect of overexpression of human aldehyde dehydrogenase 2 in LLC-PK1 cells on glyceryl trinitrate biotransformation and cGMP accumulation

BACKGROUND AND PURPOSE

Recent studies suggest a primary role for aldehyde dehydrogenase 2 (ALDH2) in mediating the biotransformation of organic nitrates, such as glyceryl trinitrate (GTN), to the proximal activator of soluble guanylyl cyclase (sGC), resulting in increased cGMP accumulation and vasodilation. Our objective was to assess the role of ALDH2 in organic nitrate action using a cell culture model.

EXPERIMENTAL APPROACH

Porcine renal epithelial (LLC-PK1) cells possess an intact NO-sGC-cGMP signaling system, and can be used as a biochemical model of organic nitrate action. We used a pcDNA3.1-human ALDH2 expression vector to establish a stably transfected cell line (PK1(ALDH2)) that overexpressed ALDH2, or small interfering RNA (siRNA) to deplete endogenous ALDH2, and assessed GTN biotransformation and GTN-induced cGMP formation.

KEY RESULTS

ALDH2 activity in the stably transfected cells was approximately sevenfold higher than wild-type cells or cells stably transfected with empty vector (PK1(vector)); and protein expression, as assessed by immunoblot analysis, was markedly increased. In PK1(ALDH2), GTN biotransformation was significantly increased as a result of increased glyceryl-1,2-dinitrate formation compared to wild-type or PK1(vector). However, the incubation of PK1(ALDH2) with 1 or 10 μM GTN did not alter GTN-induced cGMP accumulation compared with wild-type or PK1(vector) cells. Furthermore, siRNA-mediated depletion of ALDH2 had no effect on GTN-induced cGMP formation.

CONCLUSIONS AND IMPLICATIONS

In an intact cell system, neither overexpression nor depletion of ALDH2 affects GTN-induced cGMP formation, indicating that ALDH2 does not mediate the mechanism-based biotransformation of GTN to an activator of sGC.

The efficacy and safety of antiviral therapy with lamivudine to stop the vertical transmission of hepatitis B virus

The purpose of this study was to investigate the efficacy and safety of lamivudine (LAM) in stopping the vertical transmission of hepatitis B virus (HBV). Pregnant women with normal alanine transaminase (ALT) (n = 100) and with abnormal ALT (n = 100) who were positive for hepatitis B e antigen (HBeAg), and with HBV DNA (deoxyribonucleic acid) levels ≥1.0 × 107 copies/ml were enrolled in this study. One hundred volunteers (50 with normal ALT, 50 with abnormal ALT) received 100 mg of LAM daily from the 24th to 32nd week of gestation and the untreated 100 volunteers served as controls. All infants received passive-active immunoprophylaxis. Compared to the control group, the study group got a marked reduction in serum levels (P < 0.001) and high negativity (P < 0.001) of HBV DNA before delivery. They also got normalization in ALT levels as much as controls received general medication (P > 0.05). The prenatal transmission rate in the study group was significantly lower than that of the control group (P < 0.05). There were no differences in incidences of congenital malformation between the two groups (P > 0.05). LAM treatment can effectively and safely stop vertical transmission of HBV and normalize the ALT levels of pregnant women.

ISH-facilitated analysis of meiotic bivalent pairing

Chiasmata constitute one of the cornerstones of sexual reproduction in most eukaryotes. They mediate the reciprocal genetic exchange between homologues and are essential to the proper orientation of the homologous centromeres in meiosis I. As markers of recombination, they offer a cytological means of mapping. Rather than trying to accurately count individual chiasmata, we have examined properties of the mathematical relationship between frequencies of nonadorned disomic configurations in meiosis (ring, rods, and univalents) and the probabilities at which arms of the respective chromosomes are chiasmate (one or more chiasma per arm). Numerical analyses indicated that conventionally analyzed bivalents with nonidentified arms yield statistically biased estimates of chiasma probabilities under a broad range of circumstances. We subsequently analyzed estimators derived from adorned configurations with ISH-marked arms, which were found to be statistically far superior, and with no assumptions concerning interference across the centromere. We applied this methodology in the study of chromosomes 16 and 23 of cotton (Gossypium hirsutum), and estimated their arm lengths in centimorgans. The results for chromosome 23, the only one of the two chromosomes with a documented RFLP map, were consistent with the literature. Similar molecular-meiotic configuration analyses can be used for a wide variety of eukaryotic organisms and purposes: for example, providing far more powerful meiotic comparisons of genomes of chromosomes, and a rapid means of evaluating effects on recombination. Key words : meiotic configurations, chiasma frequencies, in situ hybridization, cotton.

Agrocybe aegerita polysaccharide combined with chemotherapy improves tumor necrosis factor-α and interferon-γ levels in rat esophageal carcinoma

Natural compounds have generated great interest as alternative treatments of diseases like cancer. Here, we investigated the anti-tumor mechanism of one such compound, Agrocybe aegerita polysaccharide, by assessing expression of tumor necrosis factor-α (TNF-α) and interferon-γ (IFN-γ) in rat esophageal carcinoma (EC). EC was induced in healthy Wistar rats by methyl-n-amyl nitrosamine. Subsequently, rats were administered cancer treatment daily for 4 weeks, as follows: the normal control group (the only group not treated with methyl-n-amyl nitrosamine) and model group received only distilled water; the chemotherapy group received tegafur treatment; and the combination group received tegafur combined with A. aegerita polysaccharide. In normal and combination groups, body weight increased gradually after each week of treatment (P < 0.05), while body weights did not change in model and chemotherapy groups. Using enzyme linked immunosorbent assay, we found serum TNF-α was lower in the combination group (31.56 ± 7.20 pg/L) than either the model (46.24 ± 8.52 pg/L) or chemotherapy (52.39 ± 9.16 pg/L) group, and, while higher, was more similar to the normal controls (25.08 ± 2.93 pg/L; P < 0.05), a finding that was confirmed by the immunohistochemistry of esophageal samples. In contrast, serum IFN-γ was higher in the combination group (97.20 ± 10.92 pg/L) than in either the model (76.11 ± 11.92 pg/L) or chemotherapy (76.04 ± 9.85 pg/L) group, but lower than in the normal group (117.56 ± 10.88; P < 0.05), also confirmed by immunohistochemistry. Therefore, Agrocybe aegerita polysaccharide, when combined with chemotherapy, can regulate immune function in EC, potentially by modulating cytokine activity, specifically downregulation of TNF-α and upregulation of IFN-γ.

Saponins isolated from Asparagus induce apoptosis in human hepatoma cell line HepG2 through a mitochondrial-mediated pathway

OBJECTIVE

Many scientific studies have shown that Asparagus officinalis has an antitumour effect and enhances human immunity, but the active components and the antitumour mechanisms are unclear. We investigated the effects of saponins isolated from Asparagus on proliferation and apoptosis in the human hepatoma cell line HepG2.

METHODS

HepG2 cells were treated with varying concentrations of Asparagus saponins at various times. Using mtt and flow cytometry assays, we evaluated the effects of Asparagus saponins on the growth and apoptosis of HepG2 cells. Transmission electron microscopy was used to observe the morphology of cell apoptosis. Confocal laser scanning microscopy was used to analyze intracellular calcium ion concentration, mitochondrial permeability transition pore (mptp), and mitochondrial membrane potential (mmp). Spectrophotometry was applied to quantify the activity of caspase-9 and caspase-3. Flow cytometry was used to investigate the levels of reactive oxygen species (ros) and pH, and the expressions of Bcl2, Bax, CytC, and caspase-3, in HepG2 cells.

RESULTS

Asparagus saponins inhibited the growth of HepG2 cells in a dose-dependent manner. The median inhibitory concentration (IC(50)) was 101.15 mg/L at 72 hours. The apoptosis morphology at 72 hours of treatment was obvious, showing cell protuberance, concentrated cytoplasm, and apoptotic bodies. The apoptotic rates at 72 hours were 30.9%, 51.7%, and 62.1% (for saponin concentrations of 50 mg/L, 100 mg/L, 200 mg/L). Treatment with Asparagus saponins for 24 hours increased the intracellular level of ros and Ca(2+), lowered the pH, activated intracellular mptp, and decreased mmp in a dose-dependent manner. Treatment also increased the activity of caspase-9 and caspase-3, downregulated the expression of Bcl2, upregulated the expression of Bax, and induced release of CytC and activation of caspase-3.

CONCLUSIONS

Asparagus saponins induce apoptosis in HepG2 cells through a mitochondrial-mediated and caspase-dependent pathway, suggesting that they may be a potent agent for the treatment of hepatocellular carcinoma.

SU-E-J-162: Development and Application of Internal and External Motion Tracking System

PURPOSE

In this study, we performed the experiment of correlation between internal organ movement and external abdominal surface movement for the mini pig using the developed motion tracking system.

METHODS

The experimental system was consisted with imaging acquisition part and image signal analyzing part. The image acquisition of internal organ was performed with a C-arm fluoroscopy system, and abdominal surface images were acquired with a camera and image acquisition board. The signal processing of the image was conducted using LabVIEW 8.6. The developed system was applied to a mini pig. The information of the internal organ movement was acquired with C-arm fluoroscopy system by tracking the fiducial gold maker pre-implemented into diaphragm, which was used in Cyberknife radiation therapy. The data acquisition of internal organ movement due to respiration and abdominal surface movement was performed under general anesthesia.

RESULTS

The motions of the internal and external markers were well correlated. The correlation coefficients between the AP movement of the external marker and the SI and RL movement of the internal target in the experiment using the mini pig were resulted in 0.903 and 0.905, respectively.

CONCLUSIONS

It is confirmed that high correlations between the movements of external marker and the targetassigned in diaphragm in the experimental case for the mini pig were existed. Therefore, it is possible to predict the locations of internal target from the movement of the external marker. These results show the possibility to use the DTTRT (Dynamic Tumor Tracking Radiation Therapy) system of Korea Institute of Radiological and Medical Science (KIRAMS) to clinical application of animals.