Accumulation and tolerance to cadmium heavy metal ions and induction of 14-3-3 gene expression in response to cadmium exposure in Coprinus atramentarius.

Cadmium (Cd), one of the most toxic heavy-metal pollutants, has a strong and irreversible tendency to accumulate. Bioremediation is a promising technology to remedy and control heavy metal pollutants because of its low cost and ability to recycle heavy metals. Coprinus atramentarius is recognized as being able to accumulate heavy metal ions. In this work, C. atramentarius is cultivated on a solid medium containing Cd2+ ions to analyze its ability to tolerate different concentrations of the heavy metal ion. It is found that the growth of C. atramentarius is not significantly inhibited when the concentration of Cd2+ is less than 0.6mgL-1. The accumulation capacity of C. atramentarius at different Cd2+ concentrations also was determined. The results show that 76% of the Cd2+ present can be accumulated even when the concentration of the Cd2+ is 1mgL-1. The different proteins of C. atramentarius exposed to Cd2+ were further analyzed using gel electrophoresis. A 14-3-3 protein was identified and shown to be significantly up-regulated. In a further study, a full-length 14-3-3 gene was cloned containing a 759bp open reading frame encoding a polypeptide consisting of 252 amino acids and 3 introns. The gene expression work also showed that the 14-3-3 was significantly induced, and showed coordinated patterns of expression, with Cd2+ exposure.

Two-step pH-modulated rapid assembly of trace-element-doped calcium-phosphate nanocrystals into giant porous beads in gelatin hydrosol for biomedical applications.

Biomolecule-ion interactions that occur during changes in pH value are a crucial but poorly investigated area that underlies the aggregation of inorganic nanocrystals. Meanwhile, the disorderly growth of calcium phosphate (CaP) nanocrystals is an obstacle that limits its practical applications. Herein, we have demonstrated for the first time that a simple two-step pH-adjustment process for a gelatin hydrosol reaction medium can modulate the ordered self-assembly of trace-element-doped CaP nanocrystals into porous beads. Two methods are used to adjust the initial pH value of gelatin hydrosol: One is to firstly adjust the pH value to 3.0 and then to 4.0 with acid/base solutions, whilst the other is to directly adjust the pH value to 4.0 with acid. Spherical CaP porous beads are rapidly produced through the two-step pH-adjustment process, whereas the one-step pathway results in disorderly CaP aggregates. We believe that the introduction of additives for pH adjustment is the dominant factor in disturbing the electrokinetic parameters and for driving the self-assembly of nanocrystals, whereas the nucleation of CaP nanocrystals prior to assembly is caused by the relaxation/condensation of the polypeptide network, owing to the increase in pH value on the introduction of the basic calcium salt. This method is facile and rapid and these highly bioactive porous beads are particularly promising for use in hard-tissue repair, tissue engineering, and drug delivery.

[Expression of Csk-binding protein in esophageal carcinoma and its possible implications].

OBJECTIVE: To investigate the expression of Csk-binding protein (CBP) in esophageal carcinoma and its association with the tumorigenesis and progression of esophageal cancer. METHODS: RT-PCR and Western blotting were employed to determine the expressions of CBP at the mRNA and protein levels in 50 pairs of fresh esophageal carcinoma tissue and the adjacent normal tissues. RESULTS: CBP mRNA and protein expressions in normal tissues were 1.43- and 1.28-fold higher than those in the cancer tissues, respectively (P<0.05). The expressions of CBP mRNA and protein were positively correlated (P=0.015). The decreased expressions of CBP were significantly correlated to lymph node metastasis of esophageal cancer (P<0.05). CONCLUSION: The expression of CBP gene is decreased in esophageal carcinoma, which might contribute to the tumorigenesis and progression of this malignancy.

[Expression and clinical significance of vascular endothelial growth factor in human non-small cell lung cancer].

BACKGROUND: To investigate the expression of vascular endothelial growth factor (VEGF) and its relation to clinical characteristics and prognosis of non-small cell lung cancer (NSCLC), and to study the possible mechanism of VEGF. METHODS: The expression of VEGF and intratumoral microvascular density (MVD) were determined in 96 NSCLC tissues by SP immunohistochemical method. RESULTS: VEGF was mainly stained in the cytoplasm of tumor cells. The positive rate of VEGF expression was 64.6% in 96 patients. The positive rate of VEGF expression was related to stages (P=0.041), but not to other clinical characteristics of NSCLC (P > 0.05). The expression of VEGF in high MVD group (80.4%) was significantly higher than that in low MVD group (46.7%) (P=0.001). The patients with positive VEGF expression had a significantly shorter survival duration than those with negative VEGF expression (P < 0.01). By Cox proportional hazard model analysis, the expression of VEGF and clinical stage were considered the independent predictors for the prognosis of NSCLC. CONCLUSIONS: The results suggest that VEGF plays an important role in the angiogenesis of NSCLC, and that detection of VEGF expression may be helpful to predict prognosis of NSCLC.