In vitro bioassays for monitoring drinking water quality of tap water, domestic filtration and bottled water.

BACKGROUND: Location-specific patterns of regulated and non-regulated disinfection byproducts (DBPs) were detected in tap water samples of the Barcelona Metropolitan Area. However, it remains unclear if the detected DBPs together with undetected DPBs and organic micropollutants can lead to mixture effects in drinking water. OBJECTIVE: To evaluate the neurotoxicity, oxidative stress response and cytotoxicity of 42 tap water samples, 6 treated with activated carbon filters, 5 with reverse osmosis and 9 bottled waters. To compare the measured effects of the extracts with the mixture effects predicted from the detected concentrations and the relative effect potencies of the detected DBPs using the mixture model of concentration addition. METHODS: Mixtures of organic chemicals in water samples were enriched by solid phase extraction and tested for cytotoxicity and neurite outgrowth inhibition in the neuronal cell line SH-SY5Y and for cytotoxicity and oxidative stress response in the AREc32 assay. RESULTS: Unenriched water did not trigger neurotoxicity or cytotoxicity. After up to 500-fold enrichment, few extracts showed cytotoxicity. Disinfected water showed low neurotoxicity at 20- to 300-fold enrichment and oxidative stress response at 8- to 140-fold enrichment. Non-regulated non-volatile DBPs, particularly (brominated) haloacetonitriles dominated the predicted mixture effects of the detected chemicals and predicted effects agreed with the measured effects. By hierarchical clustering we identified strong geographical patterns in the types of DPBs and their association with effects. Activated carbon filters did not show a consistent reduction of effects but domestic reverse osmosis filters decreased the effect to that of bottled water. IMPACT STATEMENT: Bioassays are an important complement to chemical analysis of disinfection by-products (DBPs) in drinking water. Comparison of the measured oxidative stress response and mixture effects predicted from the detected chemicals and their relative effect potencies allowed the identification of the forcing agents for the mixture effects, which differed by location but were mainly non-regulated DBPs. This study demonstrates the relevance of non-regulated DBPs from a toxicological perspective. In vitro bioassays, in particular reporter gene assays for oxidative stress response that integrate different reactive toxicity pathways including genotoxicity, may therefore serve as sum parameters for drinking water quality assessment.

Characterization of airborne particles and cytotoxicity to a human lung cancer cell line in Guangzhou, China.

Air pollution by airborne particles is a serious health problem worldwide. The present study was aimed at investigating the concentrations and composition of total suspended particles (TSPs) and PM2.5 at various industrial/commercial sites of Guangzhou, a megacity of Southern China. Major and trace elements, ions and carbonaceous fraction were determined and main components were calculated. In addition, in order to assess the potential toxic on the respiratory system of these PM, cytotoxicity of size-fractionated particles (PM10-5.6, PM5.6-3.3, PM3.3-1.1, PM1.1-0.43) for a human lung cancer cell line (A549) was also investigated. Correlations between PM constituents and toxicity were assessed. Median levels of TSPs and PM2.5 in industrial/commercial sites were 206 and 57.7 µg/m3, respectively. Nickel, Cu, Mo, Mn, Pb, and Ti were the most abundant metals in TSPs and PM2.5. Industrial activities and coal combustion were the most important sources of carbonaceous particles in the zone. MTT assays showed that PM10-5.6 and PM1.1-0.43 had the highest and the lowest cytotoxicity to A549 cell lines, respectively. Inhalable particles around the manufacturing of metal facilities and formal waste treatment plants showed a high cytotoxicity to A549 cell lines. In general terms, no significant correlations were found between main components of PM and toxicity. However, W showed a significant correlation with cell viability.

[Reversion of overweight and obesity in Vilafranca del Penedès child population: ACTIVA'T Program (2012)]. / Reversión de sobrepeso y obesidad en población infantil de Vilafranca del Penedès: Programa ACTIVA'T (2012).

OBJECTIVE: To assess a 6-month nutritional and physical activity intervention program on the nutritional status of overweight or obese and not very active 8-14 years old children by means of a controlled pre-post design (ACTIVA'T program). METHOD: Pre-post study in 8-14 years old overweight or obese and low active children from Vilafranca del Penedès (Barcelona, Spain) randomized in control group (n = 51, 47.1% girls, nutritional intervention and ≤3h/wk physical activity) and ACTIVA'T group (n = 45, 37.8% girls, nutritional and physical activity ≥5h/wk intervention). Body mass index, waist/height index, and diet quality by means of KIDMED test at the beginning and at the end of the program were assessed. During the intervention, each participant was accompanied by a relative (father or mother) who performed the same activities as the children. RESULTS: Dietary recommendations have positively changed the habits of both ACTIVA'T and control group. The reversion in the prevalence of overweight and obesity was 93.8% and 58.6%, respectively, in the ACTIVA'T group, compared to 25.0% and 35.8% in the control group. Abdominal obesity was decreased from 42.2% to 17.8% in the ACTIVA'T group and from 47.1% to 27.5% in the control group. CONCLUSIONS: The program ACTIVA'T (nutritional education and physical activity promotion) improves the quality of diet and reverses the prevalence of overweight and obesity in the underactive child population.

Oral exposure to silver nanoparticles increases oxidative stress markers in the liver of male rats and deregulates the insulin signalling pathway and p53 and cleaved caspase 3 protein expression.

The present study was aimed at assessing the impact of AgNPs on the liver of male rats orally exposed to 0, 50, 100 and 200 mg/kg/day of polyvinyl pyrrolidone coated AgNPs (PVP-AgNPs) for 90 days. The induction of apoptotic cell death -by measuring the protein levels of the active form of caspase 3- and the levels of the microtubule-associated protein 1A/1B-light chain (LC3) protein were measured as a marker of the induction of autophagy. PVP-AgNPs caused an increase of the activity of superoxide dismutase (SOD) and catalase (CAT) in the liver of male rats. However, the activity decreased after exposure to high amounts of PVP-AgNPs. Increased protein levels of IRS-1, AKT, GSK3ß and mTOR proteins were observed in a dose-dependent manner. However, these proteins showed a decrease at 200 mg/kg/day. The same pattern was observed for the p53, p21 and cleaved caspase 3 protein levels. The current results suggest that the increase of ROS production by PVP-AgNPs stimulated SOD and CAT activity, as well as IRS-1, AKT, mTOR, p53, p21 and caspase 3 as protective mechanisms of cell survival and preserve DNA fidelity. However, cellular damage by excessive ROS production might induce the depletion of these survival mechanisms at 200 mg/kg/day.

Resveratrol Potently Counteracts Quercetin Starvation-Induced Autophagy and Sensitizes HepG2 Cancer Cells to Apoptosis.

SCOPE: Resveratrol (RSV) has been described as a potent antioxidant, antisteatotic, and antitumor compound, and it has also been identified as a potent autophagy inducer. On the other hand, quercetin (QCT) is a dietary flavonoid with known antitumor, anti-inflammatory, and antidiabetic effects. Additionally, QCT increases autophagy. To study the hypothetical synergistic effect of both compounds, we test the combined effect of QCT and RSV on the autophagy process in HepG2 cells. METHODS AND RESULTS: Autophagy is studied by western blotting, real-time RT-PCR, and cellular staining. Our results clearly indicate a bifunctional molecular effect of RSV. Both polyphenols are individually able to promote autophagy. Strikingly, when RSV is combined with QCT, it promotes a potent reduction of QCT-induced autophagy and influences proapoptotic signaling. CONCLUSION: RSV acts differentially on the autophagic process depending on the cellular energetic state. We further characterize the molecular mechanisms related to this effect, and we observe that AMP-activated protein kinase (AMPK) phosphorylation, heme oxygenase 1 (HO-1) downregulation, lysosomal membrane permeabilization (LMP), and Zinc (Zn2+ ) dynamics could be important modulators of such RSV-related effects and could globally represent a promising strategy to sensitize cancer cells to QCT treatment.

[Improving diet quality in children through a new nutritional education programme: INFADIMED]. / Mejora de la calidad de la dieta y del estado nutricional en población infantil mediante un programa innovador de educación nutricional: INFADIMED.

OBJECTIVE: To assess the results of a nutritional education programme developed by using available local resources to improve diet quality and decrease overweight and obesity prevalence among children. METHOD: A longitudinal intervention study by means of nutritional education (INFADIMED) in children (aged 3-7 years) from Vilafranca del Penedès (Barcelona, Spain), recruited from preschool centres and primary schools, with an intervention or INFADIMED group (n=319; 50.2% female) and a control group (n=880; 49.8% female). Weight, height and body mass index were measured in both groups at the beginning and at the end of the programme. Adherence to the Mediterranean diet was also assessed using the KIDMED test. RESULTS: Consumption of fruit or juices, vegetables, yogurt and/or cheese, pasta or rice, and nuts increased, while skipping breakfast, consumption of bakery products for breakfast, and/or consumption of sweets several times per day decreased in the INFADIMED group. INFADIMED also changed, from the beginning to the end of the study, the adherence to a Mediterranean diet: high (39.2% to 70.5%), acceptable (49.2% to 28.2%), and low (11.6% to 1.3%). Approximately 2.6% of the participants in the control group and 11.3% of the participants in the INFADIMED group who were overweight and obese changed to normal weight (odds ratio: 4.08; 95% confidence interval: 2.37-7.04). CONCLUSIONS: INFADIMED is a nutritional education programme with benefits on both diet quality and overweight and obesity prevalence among children.

Mechanochemically synthesized Ag-based nanohybrids with unprecedented low toxicity in biomedical applications.

A simple and innovative mechanochemical approach was employed to synthesize Ag-polysaccharide nanohybrid materials that were proved to exhibit remarkable surface properties and structures for biomedical applications. The synthesized Ag nanomaterials possessed an unprecedented low cytotoxicity against human cell lines A549 and SH-SY5Y as compared to similarly reported Ag nanomaterials due to the stability and low release of Ag+ and high biocompatibility of the nanohybrids.

Polyvinyl pyrrolidone-coated silver nanoparticles in a human lung cancer cells: time- and dose-dependent influence over p53 and caspase-3 protein expression and epigenetic effects.

The present study was aimed at providing a better understanding of the influence of silver nanoparticles (AgNPs) on the p53 tumor suppressor protein. Cell line A549 was exposed to a range of concentrations of AgNPs, and a time course (up to 72 h) of cell viability was determined. We also determined the time course of gene and protein expression of p53, p21, murine double minute 2 (MDM2) and caspase-3. The expression of all of these proteins was also determined after daily exposure of the cells to 10 µg/mL of AgNPs for 7 days, or after discontinuous exposure by treating the cells every 3 days, for 15 or 30 days. Moreover, epigenetic changes in the acetylation of the histone H3 protein and in global DNA methylation patterns were determined after 72 h of exposure. Results showed that daily exposure to low doses of AgNPs, or a single exposure to high concentrations for 72 h, decreased gene and protein expression of p53, p21, MDM2 and caspase-3 in A549 cells. In contrast, a discontinuous exposure to low doses or a single exposure to low concentrations for 72 h increased the levels of the active forms of p53 and caspase-3, as well as the p21 and MDM2 protein levels. In addition, exposure to high concentrations of AgNPs for 72 h induced higher levels of global DNA methylation and global histone H3 deacetylation in A549 cells. These results provide new information on the toxic action of AgNPs.

Oral subchronic exposure to silver nanoparticles in rats.

Because of their extremely small size, silver nanoparticles (AgNPs) show unique physical and chemical properties, with specific biological effects, which make them particularly attractive for being used in a number of consumer applications. However, these properties also influence the potential toxicity of AgNPs. In this study, we assessed the potential toxic effects of an in vivo oral sub-chronic exposure to polyvinyl pyrrolidone coated AgNPs (PVP-AgNPs) in adult male rats. We also assessed if oral PVP-AgNPs exposure could alter the levels of various metals (Fe, Mg, Zn and Cu) in tissues. Rats were orally given 0, 50, 100 and 200 mg/kg/day of PVP-AgNPs. Silver (Ag) accumulation in tissues, Ag excretion, biochemical and hematological parameters, metal levels, as well as histopathological changes and subcellular distribution following PVP-AgNPs exposure, were also investigated. After 90 days of treatment, AgNPs were found within hepatic and ileum cells. The major tissue concentration of Ag was found in ileum of treated animals. However, all tissues of PVP-AgNPs-exposed animals showed increased levels of Ag in comparison with those of rats in the control group. No harmful effects in liver and kidney, as well as in biochemical markers were noted at any treatment dose. In addition, no hematological or histopathological changes were found in treated animals. However, significant differences in Cu and Zn levels were found in thymus and brain of PVP-AgNPs-treated rats.

A novel cancer-germline transcript carrying pro-metastatic miR-105 and TET-targeting miR-767 induced by DNA hypomethylation in tumors.

Genome hypomethylation is a common epigenetic alteration in human tumors, where it often leads to aberrant activation of a group of germline-specific genes, commonly referred to as "cancer-germline" genes. The cellular functions and tumor promoting potential of these genes remain, however, largely uncertain. Here, we report identification of a novel cancer-germline transcript (CT-GABRA3) displaying DNA hypomethylation-dependent activation in various tumors, including melanoma and lung carcinoma. Importantly, CT-GABRA3 harbors a microRNA (miR-105), which has recently been identified as a promoter of cancer metastasis by its ability to weaken vascular endothelial barriers following exosomal secretion. CT-GABRA3 also carries a microRNA (miR-767) with predicted target sites in TET1 and TET3, two members of the ten-eleven-translocation family of tumor suppressor genes, which are involved in the conversion of 5-methylcytosines to 5-hydroxymethylcytosines (5hmC) in DNA. Decreased TET activity is a hallmark of cancer; here, we provide evidence that aberrant activation of miR-767 contributes to this phenomenon. We demonstrate that miR-767 represses TET1/3 mRNA and protein expression and regulates genomic 5hmC levels. Additionally, we show that high CT-GABRA3 transcription correlates with reduced TET1 mRNA levels in vivo in lung tumors. Together, our study identified a cancer-germline gene that produces microRNAs with oncogenic potential. Moreover, our data indicate that DNA hypomethylation in tumors can contribute to reduced 5hmC levels via activation of a TET-targeting microRNA.

Perinatal exposure to BDE-99 causes decreased protein levels of cyclin D1 via GSK3ß activation and increased ROS production in rat pup livers.

We here examined the potential liver toxicity in rat pups from dams exposed during the gestational and lactation periods to 2,2',4,4',5-pentabromodiphenyl ether (BDE-99). Dams were exposed to 0, 1, and 2mg/kg/day of BDE-99 from gestation day 6 to postnatal day 21. When the pups were weaning, the liver from 1 pup of each litter was excised to evaluate oxidative stress markers and the messenger RNA (mRNA) expression of multiple cytochrome P450 (CYP) isoforms. To determine whether thyroid hormone (TH) was disrupted, the protein and mRNA expressions of several TH receptor (TR) isoforms, as well as the protein levels of cyclin D1 and the phosphorylated protein kinases Akt and glycogen synthase kinase 3 beta (GSK3ß), were evaluated. Perinatal exposure to BDE-99 produced decreased levels of cyclin D1 in rat pup livers. A decrease in the active form of Akt and an increase in the active form of GSK3ß were observed. The decreased Akt pathway may be due to a potential disruption of the nongenomic actions of TH by BDE-99 and its metabolites. This possible TH disruption was noted as a decrease in TR isoforms expression. By contrast, we observed an upregulation of CYP2B1 gene expression, which is correlated with an increase in reactive oxygen species production. This outcome indicates activation of the nuclear constitutive androstane receptor, which could induce the expression of other enzymes capable of metabolizing TH. The present findings support the hypothesis that perinatal exposure to PBDEs, at levels found in humans, may have serious implications for metabolic processes in rat pup livers.

BDE-99 deregulates BDNF, Bcl-2 and the mRNA expression of thyroid receptor isoforms in rat cerebellar granular neurons.

Although the disruption of thyroid hormone (TH) signaling can largely explain the neurotoxic effects of polybrominated diphenyl ethers (PBDEs), there are still many unknowns about how this interference occurs. In this study, we expose a primary culture of rat cerebellar granule neurons (CGNs) to a 25µM concentration of one of the most prevalent PBDE congeners in humans, 2,2',4,4',5-pentaBDE (BDE-99). The main goal was to investigate the time course of BDE-99 toxicity in relation to the disruption of thyroid receptor (TR) function over 24h. In a first stage, we found that BDE-99 directly down-regulated the transcription of the isoforms TR-alpha1 and TR-alpha2, which may be a consequence of a hypothetical state that mimics hyperthyroidism. In a later stage, BDE-99 disrupted the expression of triiodothyronine (T3)-responsive genes, possibly as an effect of its metabolism. A down-regulation of the expression of the T3-mediated neurotrophin brain-derived neurotrophic factor (BDNF) and the anti-apoptotic Bcl-2 protein was also observed. Down-regulation of these two proteins was correlated with an increase in the production of reactive oxygen species (ROS). It was also found that expression of the TR-beta1 isoform, which is normally transcriptionally repressed by T3 in CGNs, was up-regulated. This up-regulation could compensate the down-regulation of the TR-alpha1 isoform, and thus slow down cell death. The dually disruptive action of BDE-99 might provide a better understanding of the potentially neurotoxic mechanism of PBDEs.

[Laparoscopic surgery in cancer of the esophagus]. / Cirugía laparoscópica en el cáncer de esófago.

INTRODUCTION: For the last year we have substituted laparotomy with laparoscopy for the abdominal stage of esophageal cancer surgery. We report our experience of the introduction of video-assisted surgery in the treatment of esophageal cancer. PATIENTS AND METHOD: We report our experience of nine patients diagnosed with esophageal cancer. In seven patients laparoscopy was preceded by right thoracotomy and esophageal dissection. Then, a left anterolateral cervicotomy was performed to remove the specimen and to construct the esophagogastroanastomosis. In two patients the laparoscopic technique was performed first and the Ivor Lewis procedure was completed by right thoracotomy. RESULTS: Due to the reduced number of operated patients, the results are of little significance. Morbidity was 38.3%. The mean duration of the surgical procedure in laparoscopic patients was 4 h 50 min. However, perioperative blood loss, postoperative complications, analgesic requirements and mean length of hospital stay were reduced. CONCLUSIONS: Video-assisted esophagectomy can be performed as safely as conventional esophagectomy and has considerable perioperative advantages. The introduction of the laparoscopic procedure is the first step in using video-assisted surgery at all stages of esophageal cancer surgery.