A Broad-Specificity Chitinase from Penicillium oxalicum k10 Exhibits Antifungal Activity and Biodegradation Properties of Chitin.

Penicillium oxalicum k10 isolated from soil revealed the hydrolyzing ability of shrimp chitin and antifungal activity against Sclerotinia sclerotiorum. The k10 chitinase was produced from a powder chitin-containing medium and purified by ammonium sulfate precipitation and column chromatography. The purified chitinase showed maximal activity toward colloidal chitin at pH 5 and 40 °C. The enzymatic activity was enhanced by potassium and zinc, and it was inhibited by silver, iron, and copper. The chitinase could convert colloidal chitin to N-acetylglucosamine (GlcNAc), (GlcNAc)2, and (GlcNAc)3, showing that this enzyme had endocleavage and exocleavage activities. In addition, the chitinase prevented the mycelial growth of the phytopathogenic fungi S. sclerotiorum and Mucor circinelloides. These results indicate that k10 is a potential candidate for producing chitinase that could be useful for generating chitooligosaccharides from chitinous waste and functions as a fungicide.

Upregulation of miR-543-3p promotes growth and stem cell-like phenotype in bladder cancer by activating the Wnt/ß-catenin signaling pathway.

The Wnt/ß-catenin signaling pathway, which is strictly controlled by multiple negative regulators, has been reported commonly hyper activated and closely related to the progression of bladder cancer. However, how tumor cells override the negative regulatory effects to maintain constitutive activation of Wnt/ß-catenin signaling is still unclear. In the current study, we demonstrated that upregulation of miR-543-3p in bladder cancer activated Wnt/ß-catenin signaling by directly targeting Wnt inhibitory factor 1 (WIF1) and Dickkopf 1 (DKK1), which are important antagonist molecules of the Wnt/ß-catenin pathway. Expression of miR-543-3p was upregulated in both bladder cancer tissues and cells, and positively correlated with high-grade bladder cancer. Furthermore, ectopic overexpression of miR-543-3p promoted proliferation and inhibited apoptosis in bladder cancer cells. Notably, overexpression of miR-543-3p enhanced, while silencing miR-543-3p reduced, stem cell-like phenotype of bladder cancer cells. Therefore, our results suggest that miR-543-3p plays a significant role in promoting proliferation and stem cell-like phenotype in bladder cancer, which might be a potential target for anti-bladder cancer therapy.

The effect of phosphodiesterase isoenzyme 5 inhibitors on ureteropelvic junction obstruction in rabbits.

OBJECTIVE: To determine the effects of phosphodiesterase isoenzyme 5 (PDE5) inhibitors upon ureteropelvic junction obstruction (UPJO) in rabbits. MATERIALS AND METHODS: Twenty-four New Zealand rabbits were randomly divided into three groups: sham-operated animals (group A; right-sided operations comprised subgroup A1 and left-sided operations comprised subgroup A2), operated animals (group B) and operated animals that received vardenafil (group C). The right-sided junctions of group A (A1) were not exposed, and therefore made up the control group. The UPJO model was established by partial obstruction of the left junction. Intravenous pyelograms were performed before and after the operation. HE staining and microscopic examinations were performed to chart the pathological changes. Immunohistochemistry (streptavidin peroxidase) was used to test the expression of TGF-beta1 and nNOS in the junctions. RT-PCR detected mRNA expression of TGF-beta1. RESULTS: We observed serious hydronephrosis in group B and moderate hydronephrosis in group C, but not in group A. We also observed large pathological changes in group B, but little change in group C and no change in subgroups A1 and A2. The level of TGF-beta1 in group B was significantly higher than in groups A and C; group C expressed more TGF-beta1 than group A. More nNOS was detected in group C than group B, although the two groups both expressed nNOS at lower levels than group A. CONCLUSIONS: More TGF-beta1 and less nNOS are expressed when the junction is obstructed. PDE5 inhibitors may be able to regulate these 2 factors, or other factors that have not been discussed in this experiment, in order to halt the progression of UPJO.

[Discussion on pharmacological mechanism of laosun kangfu tablets].

OBJECTIVE: to study pharmacological mechanism of Laosun Kangfu tablet. METHOD: Blood-activating and stasis-removing was tested by establishing cute cold pathogens induced blood stasis rat model and microcirculation disturbance state rat model by means of dripping adrenine on the mensentery. The resisting oxidation was tested by establishing the freely falling body damages models. The kidney-notifying was tested by Acetic acid hydrocortisone-caused kidney asthenia of mice. RESULT: All of the experimental results showed that there were Significant differences between the treatment groups and the control groups, such as promoting blood circulation and removing blood stasis, resisting the oxidation, the kidney-notifying actions. CONCLUSION: Effects of Huoxue Xiaozhong and Xingqi Zhitong of Laosun Kangfu tablet is because the action of improving microcirculation, antioxidation and regulating endocrine.

[Effect of electroacupuncture on free radical content and HSP70 expression in the brain tissue in rats with cerebral ischemia-reperfusion injury].

OBJECTIVE: To study the mechanism of electroacupuncture (EA) in treating ischemic cerebrovascular disease. METHODS: Reversible cerebral ischemia/reperfusion (CI/R) model of rats was established by occlusion of the middle cerebral artery and reperfusion. Sixty-three Wistar rats were randomized into sham-operation, CI-2 h/R-1 h, CI-2 h/R-1 h+ EA, CI-2 h/R-3 h, CL-2 h/R-3 h+EA, CI-2 h/R-6 h, CI-2 h/R-6 h+ EA groups with 9 cases being in each group. EA (4/60 Hz in frequency, 2 mA) was applied to "Shuigou" (GV 26), "Zhongchong" (PC 9) and "Fengfu"(GV 16) for 15 min. After decapitation, the rats' brain tissue was collected for detecting superoxide dismutase (SOD) activity and malondialdehyde (MDA) content by using nitroblue tetrazolium hydroxylamine method and thiobarbituric barbiturate reaction method separately. HSP70 expression was measured by immunohistochemical technique. RESULTS: Compared with sham-operation group, SOD activity in CI-2 h/R-1 h, CI-2 h/R-3 h and CI-2 h/R-6 h groups decreased obviously (P < 0.01), and MDA contents in these 3 CI/R groups increased obviously (P < 0.01), while compared with their corresponding CI/R groups, SOD activity increased considerably and MDA contents lowered apparently in the CL-2 h/R-1 h+ EA, CI-2 h/R-3 h+ EA and CI-2 h/R-6 h+ EA groups (P < 0.05, 0.01). HSP70 expression presented a marked increase tendency in the 3 CI/R groups and after EA the expression increased further. CONCLUSION: EA can raise SOD activity, lower MDA content in the brain tissue and enhance HSP70 expression in CI/R rats.