[Simultaneous production of hydrogen and volatile fatty acid from Macrocystis pyrifera].

Batch experiments were conducted to analyze the effects of pretreatment conditions, inoculum-substrate ratio (ISR) and initial pH on the hydrogen and volatile fatty acid (VFA) production from anaerobic digestion of Macrocystis pyrifera biomass. The results indicated that M. pyrifera could produce hydrogen and VFA simultaneously. In addition, thermo-alkaline pretreatment was proved as the best method for hydrogen and VFA production. The optimal pretreatment conditions, ISR, initial pH value were determined as thermal-alkaline pretreatment at 100 degrees C with 4 g x L(-1) NaOH, 0.3 and 6, respectively. Under these conditions, the maximum hydrogen production was 36.21 mL x g(-1) per unit volatile solids, which resulted in 77.82% improvement compared with the yield from untreated M. pyrifera. Furthermore, the TVFA yield under the optimal conditions was found to be 0.15 g x g(-1) per unit volatile solids and the VFAs mainly consisted of acetate and butvrate

[Expression of phosphatase and tensin homolog in lower rectal cancer on neoadjuvant chemoradiotherapy].

OBJECTIVE: To explore the expression of phosphatase and tensin homolog deleted on chromosome ten (PTEN) in low rectal cancer on neoadjuvant chemoradiotherapy with capecitabine plus radiotherapy. METHODS: Sixty-six patients with low rectal cancer on therapy with capecitabine (1650 mg×m(-2)×d(-1) in 2 divided doses) for two course and concurrent radiotherapy (50 Gy, 2 Gy/day, 5 days a week). Then the investigators analyzed the relationship between the preoperative neoadjuvant chemoradiotherapy and prognosis and measured the expression of PTEN during neoadjuvant chemoradiotherapy. RESULTS: 92.4% (61/66) of patients received neoadjuvant chemoradiotherapy as planned. 87.9% (58/66) tumor stages were down-staged, tumor size decreased while the distance from anal edge increased. And curative resection with sphincter-sparing was carried out in all patients. The rate of sphincter preservation was 90.9% (60/66). Among which, 85.5% patients showed an excellent function of sphincter. The 2-year survival rate was 87.9% (58/66). The survival period was an average of 35.3 months (range: 25-60). The PTEN mRNA and protein expression in cancer tissues on neoadjuvant chemoradiotherapy were significantly higher than those before neoadjuvant chemoradiotherapy (P=0.0079, 0.0269). CONCLUSIONS: The preoperative neoadjuvant chemoradiotherapy in lower rectal cancer patients has shown its efficacy in down-staging cancer, enhancing resectability, offering sphincter preservation, up-regulating PTEN expression, promoting the apoptosis of cancer cell and achieving a better survival rate. Thus preoperative neoadjuvant chemoradiotherapy is an effective adjuvant measure.