[Characterization of Ambient Volatile Organic Compounds, Source Apportionment, and the Ozone-NOx-VOC Sensitivities in Liucheng County, Guangxi].

Liucheng county, as a suburb of Liuzhou City in Guangxi province, has a prominent ozone (O3) pollution problem; however, there have been no relevant analyses of the cause of local O3 pollution reported. In order to investigate the causes of O3 pollution, an online observation of 116 VOCs with a time resolution of 1 h was carried out in Liucheng county from October 1st to 15th, and the sensitivity of ozone to the relative changes in the NOx and VOCs was analyzed. The results showed that the average value of φï¼»total volatile organic compounds (TVOCs)ï¼½ during the observation period was 27.52×10-9, and the average value of φ(TVOCs) during the polluting process (October 1st to 6th) was 32.15×10-9, which was 32.79% higher than that of the non-pollution process (October 8th to 15th). In terms of species concentration, oxygenated volatile organic compounds (OVOCs) contributed the highest, accounting for 43.70%, followed by alkanes (23.00%), aromatics (11.75%), and halocarbons (7.35%). In terms of ozone formation potential (OFP), OVOCs contributed the highest (41.96%) to OFP, followed by aromatics (32.60%) and alkenes (17.92%). During the observation period, VOCs mainly came from motor vehicle emissions (32.44%), biomass combustion sources (29.31%), solvent use sources (16.43%), plant sources (11.34%), and chemical industry emissions (10.49%). The contribution ratios of solvent use sources and plant sources in the pollution process increased by 28.58% and 28.53%, respectively. The EKMA curve shows that, during the observation period, Liucheng county was in a synergistic control area for VOCs and nitric oxide (NOx). Therefore, in the high ozone-occurrence autumn of Liucheng county, the key will be to reduce both VOCs and NOx emissions.

[Obesity and Bone Mineral Density in Menopausal Women].

OBJECTIVES: To determine the association between obesity and bone mineral density in menopausal women. METHODS: We recruited menopausal women aged 50 years and older who undertook health examinations in West China Hospital of Sichuan University in this study. Bone mineral density of the participants was measured by MetriScan Bone Densitometry. The participants were categorized into three groups according to the T value: normal density, osteopenia and osteoporosis. RESULTS: Of the 4 938 participants, 8.55% had obesity [body mass index (BMI)>28 kg/m2]. The three groups of participants were different in BMI, a body shape index (ABSI), body mass, waist circumference, hip circumference and height ( P<0.01). The age-adjusted T values were positively correlated with height, body mass, waist circumference, hip circumference, waist-hip ratio (WHR), waist-height ratio (WHtR) and body roundness index (BRI) ( P<0.05). The areas under curves (AUC) of receiver operator characteristic (ROC) were 0.540 and 0.568, respectively, for waist circumference and BMI in those with osteoporosis. CONCLUSIONS: Obesity in menopausal women is negatively associated with osteoporosis. The clinical significance of such an association requires further studies with a longitudinal design.

RTEF-1 protects against oxidative damage induced by H2O2 in human umbilical vein endothelial cells through Klotho activation.

Oxidative stress is a main risk factor of vascular aging, which may lead to age-associated diseases. Related transcriptional enhancer factor-1 (RTEF-1) has been suggested to regulate many genes expression which are involved in the endothelial angiogenesis and vasodilation. However, whether RTEF-1 has a direct role in anti-oxidation and what specific genes are involved in RTEF-1-driven anti-oxidation have not been elucidated. In this study, we found that overexpressing RTEF-1 in H2O2-treated human umbilical vein endothelial cells decreased senescence-associated-ß-galactosidase (SA-ß-gal)-positive cells and G0/G1 cells population. The expressions of p53 and p21 were decreased in H2O2-treated RTEF-1 o/e human umbilical vein endothelial cells. However, specific small interfering RNA of RTEF-1 totally reversed the anti-oxidation effect of RTEF-1 and inhibited RTEF-1-induced decreased p53 and p21 expressions. It demonstrated that RTEF-1 could protect cells from H2O2-induced oxidative damage. In addition, we demonstrated that RTEF-1 could up-regulate Klotho gene expression and activate its promoter. Furthermore, Klotho small interfering RNA significantly blocked RTEF-1-driven endothelial cell protection from H2O2-induced oxidative damage and increased p53 and p21 expressions. These results reveal that RTEF-1 is a potential anti-oxidation gene and can prevent H2O2-induced endothelial cell oxidative damage by activating Klotho.

Management of primary gastric small cell carcinoma in China.

BACKGROUND: Primary gastric small cell carcinomas (GSCCs) are increasingly identified by endoscopy, and account for 15-20% of all gastric neuroendocrine tumors (NETs). GSCCs have the worst prognosis with the highest rate of metastases. PURPOSE: To provide useful information for clinicians and researchers to better manage patients with GSCC, we studied the clinical features of GSCC and explored the corresponding therapies and prognosis. METHODS: A literature search was conducted through PUBMED, EMBASE, CNKI and WanFang Databases using search terms "stomach" or "gastric" and "small cell carcinoma" or "poorly differentiated neuroendocrine carcinoma", for the period 1999 to 2012. And the cases reported were all from China. Relevant articles were identified through manual review. The reference lists of these articles were reviewed to include further appropriate articles. RESULTS: Two hundred and five eligible cases were analyzed. The median age of patients was 62 years, with a male-to-female ratio of 5.4:1. Of the tumors, 53.17% were located in the upper stomach, 25.37% in the mid, 18.54% in the distal stomach, the remaining 2.93% were found in the total stomach. The mean size was 68mm in maximum diameter, with a range of 15-150 mm. Of the one hundred and thirty-five patients, fifty appeared to be pure GSCCs, eighty-five were mixed. The median overall survival time of 195 patients was 18.50 months. The 1-, 2-, and 5-year average survival rates of 142 patients were 66.75%, 37.13%, and 20.15%, respectively. CONCLUSIONS: GSCC is a rare tumor and it is notoriously aggressive with a strong propensity for both regional and distant spread. Therapies including surgical resection, chemotherapy, and local radiotherapy, by itself or in combination with other treatment, have been used to treat GSCCs in China. To identify the most effective treatment modalities for GSCCs, we still need prospective, multicenter, randomized clinical researches.

Behavior of the edible seaweed Sargassum fusiforme to copper pollution: short-term acclimation and long-term adaptation.

Aquatic agriculture in heavy-metal-polluted coastal areas faces major problems due to heavy metal transfer into aquatic organisms, leading to various unexpected changes in nutrition and primary and/or secondary metabolism. In the present study, the dual role of heavy metal copper (Cu) played in the metabolism of photosynthetic organism, the edible seaweed Sargassum fusiforme, was evaluated by characterization of biochemical and metabolic responses using both 1H NMR and GC-MS techniques under acute (47 µM, 1 day) and chronic stress (8 µM, 7 days). Consequently, photosynthesis may be seriously inhibited by acute Cu exposure, resulting in decreasing levels of carbohydrates, e.g., mannitol, the main products of photosynthesis. Ascorbate may play important roles in the antioxidant system, whose content was much more seriously decreased under acute than that under chronic Cu stress. Overall, these results showed differential toxicological responses on metabolite profiles of S. fusiforme subjected to acute and chronic Cu exposures that allowed assessment of impact of Cu on marine organisms.

Suppression of Ku80 correlates with radiosensitivity and telomere shortening in the U2OS telomerase-negative osteosarcoma cell line.

Ku70/80 heterodimer is a central element in the nonhomologous end joining (NHEJ) DNA repair pathway, Ku80 playing a key role in regulating the multiple functions of Ku proteins. It has been found that the Ku80 protein located at telomeres is a major contributor to radiosensitivity in some telomerase positive human cancer cells. However, in ALT human osteosarcoma cells, the precise function in radiosensitivity and telomere maintenance is still unknown. The aim of this study was to investigate the effects of Ku80 depletion in the U2OS ALT cell line cell line. Suppression of Ku80 expression was performed using a vector-based shRNA and stable Ku80 knockdown in cells was verified by Western blotting. U2OS cells treated with shRNA-Ku80 showed lower radiobiological parameters (D0, Dq and SF2) in clonogenic assays. Furthermore, shRNA-Ku80 vector transfected cells displayed shortening of the telomere length and showed less expression of TRF2 protein. These results demonstrated that down-regulation of Ku80 can sensitize ALT cells U2OS to radiation, and this radiosensitization is related to telomere length shortening.

[Effects of hypoxia on the expression of angiotensin-converting enzyme 2 in human umbilical vein endothelial cells].

OBJECTIVE: To study the influence and mechanism of hypoxia on the expression of angiotensin-converting enzyme 2 (ACE2) in human umbilical vein endothelial cells (HUVECs). METHODS: HUVECs were cultured as adherent cells and identified by immunohistochemical study of Factor VIII. Then the cells were cultured in 37 degrees C incubators under hypoxia condition (1% O2 + 94% N2 + 5%C O2) or regular 5% CO2 condition for 3 h, 6 h, 12 h, 24 h, respectively, and the culture medium and cells were collected at each time point. ACE2 protein was measure by immunohistochemical assay, ACE2 mRNA was quantified by real-time RT-PCR. RESULTS: (1) ACE2 protein expression decreased after hypoxia treatment for 3 h, 6 h, 12 h, and 24 hour compared with regular oxygen condition (chi2 = 825.078, 768.141, 623.931, 350.260, P < 0.00625), the maximum reduction came at 3 h after hypoxia exposure, then raised gradually after 6 h, 12 h, and 24 h exposure; (2) ACE2 mRNA expression show a similar tendency to ACE2 protein. After hypoxia disposal, its relative expression rate reduced to 0.281 at 3 h (P = 0.031), then increased gradually at 6 h (0.445, P = 0.034), 12 h (0.794, P = 0.434), 24 h (0.891, P = 0.692). CONCLUSION: Our study show hypoxia down-regulate the protein and gene expression of ACE2 in HUVECs in 24 hours. The down-regulation effect of hypoxia reached maximum level at 3 h, and then attenuated gradually at 6 h, 12 h and 24 h, which indicate that ACE2 might play an important role in the regulation of RAS in HUVECs after hypoxia injury.

[AQP1 expression in vascular endothelial cells in vitro under hypoxia conditions].

OBJECTIVE: To investigate the expression of AQP1 in endothelial cells under hypoxia conditions in vitro. METHODS: The cultured human umbilical vein endothelial cells were randomly assigned to hypoxia groups (exposed to 1% of O2 for 3 h, 6 h, 12 h and 24 h respectively), and control group (ordinary culture). The expressions of AQP1 mRNA and protein were detected by real time PCR and immunohistochemistry respectively. RESULTS: The expressions of AQP1 protein and mRNA increased after exposure to hypoxia initially and then decreased afterwards. CONCLUSION: Hypoxia regulates the expression of AQP1 in vascular endothelial cells.