[A triple-wavelength visible spectroscopic method for determination of iron content in lignocellulosic materials].

The present paper described a triple-wavelength visible spectroscopic method for the determination of iron content in lignocellulosic materials. After the sample was pretreated with acidic hydrolysis method under selected conditions, the color agent, 1, 10-phenanthroline monohydrate, was added in the filtrate and then measured by a triple-wavelength spectroscopic method at wavelengths of 416, 510 and 700 nm, from which the iron contents of the sample can be calculated. The results showed that this method can efficiently deduct the influences of acidic soluble lignin and furfural compounds generated during the sample pretreatment and baseline drift caused by the tiny particles in the filtrates. It not only has a good measurement precision but also is accurate, in which the relative differences of the results obtained by the present method and ICP-OES method is less than 5%. The method is simple and practical, and suitable for industrial applications.

Dieth-yl(hy-droxy)ammonium 3-carb-oxy-benzoate.

In the title molecular compound, C(4)H(12)NO(+)·C(8)H(5)O(4) (-), the N,N-dieth-yl(hy-droxy)ammonium cation (DTHA) is linked to the 3-carb-oxy-benzoate anion (HBDL) by O-H⋯O and N-H⋯O hydrogen bonds with a graph-set motif R(2) (2)(7). In the crystal, helical chains are formed by O-H⋯O hydrogen bonds, propagating along [010]. The crystal structure is further stabilized by π-π inter-actions between inversion-related HBDL benzene rings [centroid-centroid distance = 3.900 (4) Å] and C-H⋯O inter-actions.

Bis[dieth-yl(hy-droxy)ammonium] benzene-1,4-dicarboxyl-ate.

In the centrosymmetric title compound, 2C(4)H(12)NO(+)·C(8)H(4)O(4) (2-), two N,N-dieth-yl(hy-droxy)ammonium cations are linked to a benzene-1,4-dicarboxyl-ate dianion by a combination of O-H⋯O and N-H⋯O hydrogen bonds, which can be described in graph-set terminology as R(2) (2)(7). The crystal structure is further stabilized by C-H⋯O hydrogen bonds, leading to the fomation of a ribbon-like network.

Overexpression of degenerative spermatocyte homolog 1 up-regulates the expression of cyclin D1 and enhances metastatic efficiency in esophageal carcinoma Eca109 cells.

Cyclin D1 plays a pivotal role in cell-cycle transition through G1 phase. In this article, we found that Degenerative Spermatocyte Homolog 1 (DEGS1) up-regulated the expression of cyclin D1 and the activation of transcription factor NF-kappaB was essential for DEGS1-induced cyclin D1 production. Forced expression of DEGS1 in Esophageal carcinoma cell line Eca109 cells increased their ability of cell migration and significantly induced tumor metastasis in nude mice, whereas RNA interference-mediated knockdown of DEGS1 cells significantly inhibited cell migration in vitro, as well as tumor metastasis in vivo. Our results demonstrated that expression of DEGS1 up-regulated the expression of cyclin D1 and enhanced the efficiency of tumor metastasis.

Purification and relationship with gastric disease of a 130 kDa (CagA) protein of Helicobacter pylori.

OBJECTIVE: The aims of this research were to purify and identify the 130 kDa (CagA) protein of H. pylori clinical isolate HP97002 and evaluate the relationships between the purified 130 kDa (CagA) protein and gastric diseases. METHODS: The procedure for isolating the protein included 6 mol/L guanidine extract, size exclusion chromatography and elusion from gel. Sera of 68 patients with gastric diseases (44 with chronic gastritis, 15 with atrophic gastritis, 7 with peptic ulcer disease, 2 with gastric cancer) were obtained, and the serological response to CagA was studied by Western-blot using the purified protein. RESULTS: The purified protein was 130 kDa and preserved good antigenicity and revealed basic isoelectric point about of 8.1. Among 68 sera, 43 sera could recognize the purified protein associated with chronic gastritis 47.7% (21/44), atrophic gastritis 86.7% (13/15), peptic ulcer disease 100% (77), gastric cancer 100% (2/2). Compared with each other, the difference was significant (chi2 = 13.327, P = 0.004), and 130 kDa (CagA) protein was associated with severe gastric diseases ( r(S) = 0.442, P = 0.001). CONCLUSION: The 130 kDa (CagA) protein was associated with severe gastric diseases.

Effect of delayed pulsed-wave ultrasound on local pharmacokinetics and pharmacodynamics of vancomycin-loaded acrylic bone cement in vivo.

This study sought to investigate the effect of delayed pulsed-wave ultrasound with low frequency on drug release from and the antimicrobial efficacy of vancomycin-loaded acrylic bone cement in vivo and the possible mechanism of this effect. After the implantation of cement and the inoculation of Staphylococcus aureus into the bilateral hips of rabbits, ultrasound (average intensity, 300 mW/cm(2); frequency, 46.5 kHz; on/off ratio, 20 min/10 min) was applied to animals in the normal ultrasound group (UG(0-12)) from 0 through 12 h after surgery and to those in the delayed-ultrasound group (UG(12-24)) from 12 through 24 h after surgery. The control group (CG) was not exposed to ultrasound. Based on vancomycin concentrations in left hip cavities at projected time intervals, the amount of time during which the local drug concentration exceeded the MIC (T(>MIC)) in UG(12-24) was significantly prolonged compared with that in either CG or UG(0-12), and the ratios between the areas under the concentration-time curves over 24 h and the MIC for UG(0-12) and UG(12-24) were both increased compared with that for CG. The greatest reductions in bacterial densities in both right hip aspirates and right femoral tissues at 48 h were achieved with UG(12-24). Local hemorrhage in rabbits of UG(0-12) during the 12-h insonation was more severe than that in rabbits of UG(12-24). Of four variables, the T(>MIC) and the bioacoustic effect were both identified as parameters predictive of the enhancement of the antimicrobial efficacy of cement by ultrasound. Sustained concentrations above the MIC replaced early high maximum concentrations and long-term subtherapeutic release of the drug, provided that ultrasound was not applied until local hemorrhage was relieved. The enhancement of the antimicrobial efficacy of cement by ultrasound may be attributed to the prolonged T(>MIC) and the bioacoustic effect caused by ultrasound.