SANASA Capivari II - the first full-scale municipal membrane bioreactor in Latin America.

The macro region of Campinas (Brazil) is rapidly evolving with new housing developments and industries, creating the challenge of finding new ways to treat wastewater to a quality that can be reused in order to overcome water scarcity problems. To address this challenge, SANASA (a publicly owned water and wastewater concessionaire from Campinas) has recently constructed the 'EPAR (Water Reuse Production Plant) Capivari II' using the GE ZeeWeed 500D(®) ultrafiltration membrane system. This is the first large-scale membrane bioreactor (MBR) system in Latin America with biological tertiary treatment capability (nitrogen and phosphorus removal), being able to treat an average flow of 182 L/s in its first phase of construction. The filtration system is composed of three membrane trains with more than 36,000 m(2) of total membrane filtration area. The membrane bioreactor (MBR) plant was commissioned in April 2012 and the permeate quality has exceeded expectations. Chemical oxygen demand (COD) removal rates are around and above 97% on a consistent basis, with biochemical oxygen demand (BOD5) and NH3 (ammonia) concentrations at very low levels, and turbidity lower than 0.3 nephelometric turbidity unit (NTU). Treated effluent is sent to a water reuse accumulation tank (from where will be distributed as reuse water), and the excess is discharged into the Capivari River.

Gene transcription of the retinoid X receptor alpha (RXRalpha) is regulated by fatty acids and hormones in rat hepatic cells.

This work describes the molecular mechanisms of fatty acid and hormonal modulations of the retinoid X receptor alpha (RXRalpha) in rat liver cells. We examined the effects of different fatty acids (myristic, stearic, oleic, linolenic, and arachidonic acids, EPA, and the peroxisomal proliferator TTA) and several hormones (the glucocorticoid analogue dexamethasone, insulin, and retinoic acid) on the RXRalpha mRNA and protein levels in rat hepatoma cells and cultured hepatocytes. The fatty acids induced the RXRalpha gene expression resulting in up to 3-fold induction. Dexamethasone alone induced the mRNA level and, in combination with fatty acids, an additive or synergistic effect was observed. The dexamethasone-increased mRNA level was obliterated by insulin. The same pattern of regulation of the protein level was observed when determined in cultured hepatocytes, but the induced protein level showed a lower magnitude of stimulation than the mRNA level. This could indicate a post-transcriptional modulation of the RXRalpha gene expression. Time course studies showed a maximal induction of mRNA and protein levels after 18 h and 48 h, respectively. Our results uniformly show that the RXRalpha gene expression is under distinct regulation by fatty acids and hormones which suggests a coupling with the lipid metabolizing system and the hormonal signaling pathway.

Retinoid X receptor (RXR alpha) gene expression is regulated by fatty acids and dexamethasone in hepatic cells.

This work describes the molecular mechanism of fatty acid and hormonal modulation of retinoid X receptor (RXR alpha) in rat liver. We examined the effects of different fatty acids (myristic-, stearic-, linolenic-, oleic-, arachidonic- and tetradecylthioacetic acid (TTA)) and the synthetic glucocorticoid dexamethasone on RXR alpha mRNA and protein steady-state levels in hepatoma cells and cultured hepatocytes. Fatty acids induced the RXR alpha gene expression where TTA showed the most inductive effect (three-fold induction). Dexamethasone alone resulted in a stronger induction (up to seven-fold in hepatocytes), and in combination with fatty acids, an additive or synergistic effect was observed. The RXR alpha protein level in cultured hepatocytes showed a similar pattern of regulation, with a slight inductive effect of fatty acids and an additive or synergistic effect was observed in combination with dexamethasone. Our results indicate that the RXR alpha gene expression is under distinct regulation by fatty acids and dexamethasone acid which strongly suggests a coupling with the lipid metabolizing system and the retinoid signaling pathway.