Comparison of effects of 18F-FDG PET-CT and MRI in identifying and grading gliomas.

Glioma is the most common type of brain tumor. Malignant gliomas tend to have an increasingly higher incidence and are difficult to treat. Therefore, an accurate diagnosis of the grade of glioma before surgery is very important for planning surgery and determining prognosis. To compare the values of 18F-deoxyglucose positron emission tomography/computer tomography (18F-FDG PET-CT) and magnetic resonance imaging (MRI) for identifying and grading gliomas, we selected 70 patients who were diagnosed as having a primary glioma or suspected glioma at the People’s Hospital of Liaocheng in Shandong, China, and divided them into an observation group, which was examined by 18F-FDG PET-CT and a control group, which was examined by MRI. Image analysis, visual semi-quantitative analysis and qualitative analysis, follow-up and pathological results of the two groups were compared. Specificity, accuracy and sensitivity of brain MRI and PET-CT in grading the gliomas were calculated, and the results obtained were processed by Chi-squared test. Standard uptake value (SUV), SUVcorrect and L/WM (SUVmax ratio of a lesion to normal white matters in the opposite side) of FDG in the different grades of glioma were analyzed by single-factor variance analysis. Postoperative pathological detection confirmed 47 cases of glioma; the sensitivity, specificity and accuracy of PET-CT in grading glioma were all higher than those of MRI (P less than 0.05); the correlation between SUV and glioma grade, between SUVcorrect and glioma grade, and between L/WM and glioma had significant difference (P less than 0.05). Thus, it was concluded that 18F-FDG PET-CT performs better in diagnosing gliomas than MRI and is also more suitable for identifying different grades of glioma.

Effects of fruit juices, processed vegetable juice, orange peel and green tea on endogenous formation of N-nitrosoproline in subjects from a high-risk area for gastric cancer in Moping County, China.

The effects of four fruit juices, processed vegetable juice, orange peel, green tea and low dose vitamin C on endogenous N-nitrosation in 86 subjects from a high-risk area for gastric cancer in Moping County, China were studied using urinary excretion of N-nitrosoproline (NPRO) as an indicator. After ingestion of 300 mg L-proline, urinary excretion of NPRO was significantly increased from a baseline of 2.5 +/- 1.6 micrograms/day to 8.7 +/- 6.2 micrograms/day. (P < 0.001). Vitamin C (75 mg) administration significantly reduced NPRO formation (62.3%, P < 0.002) although NPRO excretion remained higher than the baseline level (4.2 +/- 1.3 vs 2.2 +/- 1.2 micrograms/day, P < 0.001). Intake of fruit juices and green tea extracts (containing 75 mg vitamin C) or of orange peel powder (containing 3 mg vitamin C) together with 300 mg L-proline inhibited NPRO formation effectively to the baseline level or to levels significantly lower than the baseline level (P < 0.05-0.005). A processed juice of a number of vegetables (300 ml) significantly catalysed endogenous nitrosation (14.7 +/- 11.8 vs 9.4 +/- 4.7 micrograms/day, P < 0.05). Endogenous N-nitrosation was unaffected by the presence of intragastric lesions. The present study shows that endogenous nitrosation in this population is profoundly affected by environmental factors and that inhibitors, such as vitamin C, alpha-tocopherol and other non-nutritive compounds in the foods do inhibit endogenous nitrosation either synergistically or in an additive manner. The significance of fruits and vegetables in prevention of human cancers is discussed.

[Study on relationship between occurrence of intragastric lesions and drinking water and nitrate intake via water in the inhabitants from a high-risk area for stomach cancer].

According to results of endoscopic and pathological evaluations of gastric mucosa, we investigated some aspects of drinking water for three groups of subjects with various intragastric lesions from a high-risk area (Moping County) for stomach cancer. Their nitrate intakes via drinking water were estimated. The results showed that the occurrence of stomach cancer and other intragastric lesions in these subjects was closely related to their drinking water quality and nitrate intake via water.

N-nitrosamines in Chinese foods.

A total of 695 different Chinese foods and ten malt samples were analysed, using gas chromatography-thermal energy analysis, for the possible presence of volatile N-nitrosamines. N-Nitrosodimethylamine (NDMA) was found in 146 of 176 beers tested at concentrations ranging from 0.1 to 6 ppb. NDMA was also detected in 201 of 271 meat products tested at concentrations ranging from 0.1 to 7.4 ppb. High levels of NDMA, up to 131.5 ppb, were detected in some seafoods and were further confirmed by gas chromatography-mass spectrometry. Milk products were found to contain less than 0.1-3.6 ppb NPYR, less than 0.1-5.7 ppb NDMA and less than 0.1-0.7 ppb NPIP, while in flavourings the nitrosamine concentrations were less than 0.1-10.3 ppb NPYR, less than 0.1-3.6 ppb NDMA and less than 0.1-0.9 ppb NPIP. Pickled vegetables contained less than 0.1-25.5 ppb NPYR and less than 0.1-15 ppb NDMA.