The neurotoxic effect of isoflurane on age-defined neurons generated from tertiary dentate matrix in mice.

INTRODUCTION: Recent animal studies showed that isoflurane exposure may lead to the disturbance of hippocampal neurogenesis and later cognitive impairment. However, much less is known about the effect of isoflurane exposure on the neurons generated form tertiary dentate matrix, even though a great increase of granule cell population during the infantile period is principally derived from this area. METHODS: To label the new cells originated from the tertiary dentate matrix, the mice were injected with BrdU on postnatal day 6 (P6). Then, the mice were exposed to isoflurane for 4 hr at 1, 8, 21, and 42 days after BrdU injection, and the brains were collected 24 hr later. The loss of newly generated cells/neurons with different developmental stage was assessed by BrdU, BrdU + DCX, BrdU + NeuN, or BrdU + Prox-1 staining, respectively. RESULTS: We found that the isoflurane exposure significantly decreased the numbers of nascent cells (1 day old) and mature neurons (42 days old), but had no effect on the immature (8 days old) and early mature neurons (8 and 21 days old, respectively). CONCLUSION: The results suggested isoflurane exposure exerts the neurotoxic effects on the tertiary dentate matrix-originated cells with an age-defined pattern in mice, which partly explain the cognitive impairment resulting from isoflurane exposure to the young brain.

Epidemiologic differences in esophageal cancer between Asian and Western populations.

Esophageal cancer is a common cancer worldwide and has a poor prognosis. The incidence of esophageal squamous cell cancer has been decreasing, whereas the incidence of esophageal adenocarcinoma has been increasing rapidly, particularly in Western men. Squamous cell cancer continues to be the major type of esophageal cancer in Asia, and the main risk factors include tobacco smoking, alcohol consumption, hot beverage drinking, and poor nutrition. In contrast, esophageal adenocarcinoma predominately affects the whites, and the risk factors include smoking, obesity, and gastroesophageal reflux disease. In addition, Asians and Caucasians may have different susceptibilities to esophageal cancer due to different heritage backgrounds. However, comparison studies between these two populations are limited and need to be addressed in the near future. Ethnic differences should be taken into account in preventive and clinical practices.

Paclitaxel based vs oxaliplatin based regimens for advanced gastric cancer.

AIM: To compare the efficacy and safety of paclitaxel combined with fluorouracil plus cisplatin (PCF), and oxaliplatin combined with fluorouracil plus leucovorin (FOLFOX-4) regimens for advanced gastric cancer (AGC). METHODS: Ninety-four patients with AGC were randomly assigned to receive paclitaxel (50 mg/m(2) iv) on days 1, 8 and 15, cisplatin (20 mg/m(2) iv) and fluorouracil (750 mg/m(2) iv) on days 1-5, or oxaliplatin (85 mg/m(2) iv) and leucovorin (200 mg/m(2) iv) on day 1, followed by bolus fluorouracil (400 mg/m(2) iv) and fluorouracil (600 mg/m(2) iv) on days 1 and 2. The primary end point was the 1-year survival time. RESULTS: The overall response rate (ORR) of the patients was 48.0% and 45.5% to PCF and FOLFOX-4, respectively. The disease control rate (DCR) of PCF and FOLFOX-4 was 82.0% and 81.8%, respectively. The median survival times (MSTs) of the patients were 10.8 and 9.9 mo, respectively, after treatment with PCF and FOLFOX-4. The 1-year survival rate of the patients was 36.0% and 34.1%, respectively, after treatment with PCF and FOLFOX-4. No significant difference was observed in ORR, DCR, MST or 1-year survival rate between the two groups. The most common adverse events were anemia, nausea and vomiting, and grade 3/4 alopecia in PCF treatment group, and anemia, grade 1/2 neurotoxic effect and grade 3/4 neutropenia in FOLFOX-4 treatment group. CONCLUSION: Patients with AGC have a similar response rate to PCF and FOLFOX-4 regimens with a similar survival rate. The PCF and FOLFOX-4 regimens are efficacious and tolerable as a promising therapy for AGC.