[Outcomes after transanal endoscopic microsurgery for early rectal cancer and risk factors associated with recurrence].

OBJECTIVE: To investigate outcomes after transanal endoscopic microsurgery (TEM) for early rectal cancer, identify risk factors associated with recurrence, and explore the indication of TEM for rectal cancer. METHODS: Sixty patients with rectal cancer undergoing TEM between June 2006 and June 2009 in the Provincial Qianfoshan Hospital of Shandong University were included in this study and data were retrospectively analyzed. RESULTS: There were 12 patients with pTis rectal cancer, 38 with pT1 and 10 with pT2. All the lesions were excised en bloc by full-thickness TEM. No positive resection margins were reported. The operative time was(65.0 ± 36.5) min. Estimated blood loss was (10.5 ± 5.8) ml and hospital stay was(4.5 ± 2.7) d. No perioperative mortality and complications occurred. The median follow-up was 28.5(range, 12-48) months. No recurrence developed in pTis lesions. There was significant difference in local recurrence rate between pT1 and pT2(2.6% vs. 40.0%, P<0.05). The recurrence rate in lesions larger than 3 cm in diameter(19.0%, 4/21) was significantly higher than that in lesions smaller than 3 cm in diameter (2.6%, 1/39) (P<0.05). Multivariate analysis showed that depth of tumour invasion(T stage) and tumour size were independently associated with recurrence after TEM. CONCLUSION: Local excision by TEM is oncologically safe and effective for pTis and pT1 rectal cancers and early lesions smaller than 3 cm in diameter.

[Effect of valproate acid sodium on apoptosis of human gastric cancer cells and its mechanism study].

OBJECTIVE: To study the effect of valproate acid sodium(VPA) on apoptosis of human gastric cancer cell BGC-823 and to explore its possible mechanism. METHODS: Cell growth inhibition was examined by MTT assay. Apoptosis rate was detected by FCM with Annexin V/PI staining. The activities and protein expression levels of caspase 3, caspase 8 and caspase 9 were examined by spectrophotometry and indirect immunofluorescence technique respectively. RESULTS: The growth inhibition rate and apoptosis rate of human gastric cancer cells, treated with 0.75-4.00 mmol/L VPA for 24 h and 48 h, elevated in time- and dose-dependent manner. Apoptosis rates of VPA 0.75 mmol/L 24 h and 48 h were (7.2 +/- 0.5)% and (9.2 +/- 1.0)%, of VPA 4.00 mmol/L 24 h and 48 h were (16.7 +/- 2.2)% and (20.4 +/- 1.6)% respectively, which were significantly different as compared to the control [24 h, (4.9 +/- 0.2)%, 48 h, (5.1 +/- 0.8)%] (P< 0.001). The activities and protein expression levels of caspase 3 and caspase 9 were up-regulated compared with the control group (P< 0.001), meanwhile the activity and protein expression of caspase 8 enhanced slightly after VPA treatment for 48 h. CONCLUSION: VPA can inhibit the growth and induce the apoptosis of BGC-823 cells mainly through the activation of caspase 9 pathway.

A taxonomic re-appraisal of Sarcocystis nesbitti (Protozoa: Sarcocystidae) from the monkey Macaca fascicularis in Yunnan, PR China.

The first detection of Sarcocystis nesbitti Mandour, 1969 in the Chinese mainland is reported and the morphology of the sarcocyst is described in detail. The parasite was detected in the monkey, Macaca fascicularis, maintained on a monkey farm in Yunnan Province; the infection may have occurred via faecal contamination from local rats, mice and/or birds. S. nesbitti was characterized as follows: a macroscopic sarcocyst, length of the cyst up to 2 mm; cyst wall smooth, thin and no perpendicular protrusion is seen under the light microscope; border of cyst wall wavy, primary cyst wall thin (38-65 nm) and invaginated; ground substance about 0.5-0.76 microm thick with electron-dense granules and concentric spherical bodies. The cyst wall is described as type 1 by electron microscopy. It is suspected that S. nesbitti may utilize Macaca mulatta, M. fascicularis, Cercocebus atys, and Papio papionis, as well as human as intermediate hosts. The taxonomy of S. nesbitti is re-appraised in the light of a consideration of possible experimental artefacts and examination of the past literature. Evidence is presented that S. nesbitti may be one of the species infecting humans in South Asia and that the monkey may be a potential reservoir host.