Assessing the potential of purple phototrophic bacteria for the simultaneous treatment of piggery wastewater and upgrading of biogas

The potential of purple phototrophic bacteria (PPB) for the simultaneous treatment of piggery wastewater (PWW) and biogas upgrading was evaluated batchwise in gas-tight photobioreactors. PWW dilution was identified as a key parameter determining the efficiency of wastewater treatment and biomethane quality in PPB photobioreactors. Four times diluted PWW supported the most efficient total organic carbon (TOC) and total nitrogen removals (78% and 13%, respectively), with CH₄ concentrations of 90.8%. The influence of phosphorous concentration (supplementation of 50 mg L^-1 of P-PO₄^3-) on PPB-based PWW treatment coupled to biogas upgrading was investigated. TOC removals of ≈60% and CH₄ concentrations of ≈90.0% were obtained regardless of phosphorus supplementation. Finally, the use of PPB and algal-bacterial consortia supported CH₄ concentrations in the upgraded biogas of 93.3% and 73.6%, respectively, which confirmed the potential PPB for biogas upgrading coupled to PWW treatment.

Removal of contaminants of emerging concern from urban wastewater in novel algal-bacterial photobioreactors

This work evaluates the removal of five pharmaceuticals and personal care products, i.e., ibuprofen, naproxen, salicylic acid, triclosan and propylparaben, from urban wastewater under two novel algal-bacterial photobioreactor settings. The first configuration (phase A) consisted of an anoxic-aerobic photobioreactor operating at a hydraulic retention time (HRT) of 2d at different concentrations of total organic carbon (TOC) (90mgL^-1-200mgL^-1). In the second configuration (phase B) an anaerobic step was introduced before the anoxic tank to set a photosynthetic A₂O process. In this phase, the HRT varied between 3 and 4d and the TOC was kept constant at 200mgL^-1. In addition, the impact of external aeration in the aerobic photobioreactor was assessed. The maximum removals for ibuprofen, naproxen, salicylic acid, triclosan and propylparaben (94±1%, 52±43%, 98±2%, 100±0%, 100±0%, respectively) were recorded during phase B. In phase A, low TOC concentrations triggered higher ibuprofen and naproxen removals likely due to the high contribution of biological oxidation on their removal. In phase B, total or very high removal efficiencies were observed for ibuprofen, propylparaben and triclosan independently on the operating conditions. In contrast, the removal efficiency of naproxen and salicylic acid decreased when the HRT dropped from 4 to 3d in the absence of external aeration, which suggests that biodegradation played a key role in their removal. In addition, sorption might have contributed to the elimination of triclosan and propylparaben from the wastewater.

Seasonal variation of biogas upgrading coupled with digestate treatment in an outdoors pilot scale algal-bacterial photobioreactor

The yearly variations of the quality of the upgraded biogas and the efficiency of digestate treatment were evaluated in an outdoors pilot scale high rate algal pond (HRAP) interconnected to an external absorption column (AC) via a conical settler. CO₂ concentrations in the upgraded biogas ranged from 0.7% in August to 11.9% in December, while a complete H₂S removal was achieved regardless of the operational month. CH₄ concentrations ranged from 85.2% in December to 97.9% in June, with a limited O₂ and N₂ stripping in the upgraded biogas mediated by the low recycling liquid/biogas ratio in the AC. Biomass productivity ranged from 0.0 g m^-2 d^-1 in winter to 22.5 g m^-2 d^-1 in summer. Finally, microalgae diversity was severely reduced throughout the year likely due to the increasing salinity in the cultivation broth of the HRAP induced by process operation in the absence of effluent.

Influence of the seasonal variation of environmental conditions on biogas upgrading in an outdoors pilot scale high rate algal pond

The influence of the daily and seasonal variations of environmental conditions on the quality of the upgraded biogas was evaluated in an outdoors pilot scale high rate algal pond (HRAP) interconnected to an external absorption column (AC) via a conical settler. The high alkalinity in the cultivation broth resulted in a constant biomethane composition during the day regardless of the monitored month, while the high algal-bacterial activity during spring and summer boosted a superior biomethane quality. CO₂ concentrations in the upgraded biogas ranged from 0.1% in May to 11.6% in December, while a complete H₂S removal was always achieved regardless of the month. A limited N₂ and O₂ stripping from the scrubbing cultivation broth was recorded in the upgraded biogas at a recycling liquid/biogas ratio in the AC of 1. Finally, CH₄ concentration in the upgraded biogas ranged from 85.6% in December to 99.6% in August.

Evaluation of the dynamics of microalgae population structure and process performance during piggery wastewater treatment in algal-bacterial photobioreactors

The dynamics of microalgae population during piggery wastewater (PWW) treatment in four open photobioreactors operated at 27days of hydraulic retention time, and inoculated with Chlorella sp. (R1), Acutodesmus obliquus (R2), Oscillatoria sp. (R3) and in the absence of inoculum (R4), were evaluated for 6months. In addition, the algal-bacterial biomass concentration, removal of organic matter, nutrients and heavy metals were also assessed. The results revealed a high diversity and rapid variations in the structure of microalgae populations, Chlorella sp. being dominant in R4 throughout most of the operational period. Steady state average biomass concentration ranged from 2445-2610mg/L in R1-R3 to 3265mg/L in R4. No significant differences were recorded in the removal efficiencies (REs) of total organic carbon (86-87%), inorganic carbon (62-71%), total nitrogen (82-85%) and total phosphorous (90-92%). Finally, Zn-REs accounted for 26% in R3, 37% in R2, and 49% in R1 and R4.

Comparative evaluation of piggery wastewater treatment in algal-bacterial photobioreactors under indoor and outdoor conditions

This work evaluated the performance of four open algal-bacterial photobioreactors operated at ≈26days of hydraulic retention time during the treatment of 10 (×10) and 20 (×20) times diluted piggery wastewater (PWW) under indoor (I) and outdoor (O) conditions for four months. The removal efficiencies (REs) of organic matter, nutrients and zinc from PWW, along with the dynamics of biomass concentration and structure of algal-bacterial population were assessed. The highest TOC-RE, TP-RE and Zn-RE (94±1%, 100% and 83±2%, respectively) were achieved indoors in ×10 PWW, while the highest TN-RE (72±8%) was recorded outdoors in ×10 PWW. Chlorella vulgaris was the dominant species regardless of the ambient conditions and PWW dilution. Finally, DGGE-sequencing of the bacterial community revealed the occurrence of four phyla, Proteobacteria being the dominant phylum with 15 out of the 23 most intense bands.

Simultaneous biogas upgrading and centrate treatment in an outdoors pilot scale high rate algal pond

The bioconversion of biogas to biomethane coupled to centrate treatment was evaluated in an outdoors pilot scale high rate algal pond interconnected to an external CO₂-H₂S absorption column (AC) via settled broth recirculation. CO₂-removal efficiencies ranged from 50 to 95% depending on the alkalinity of the cultivation broth and environmental conditions, while a complete H₂S removal was achieved regardless of the operational conditions. A maximum CH₄ concentration of 94% with a limited O₂ and N₂ stripping was recorded in the upgraded biogas at recycling liquid/biogas ratios in the AC of 1 and 2. Process operation at a constant biomass productivity of 15gm^-2d^-1 and the minimization of effluent generation supported high carbon and nutrient recoveries in the harvested biomass (C=66±8%, N=54±18%, P≈100% and S=16±3%). Finally, a low diversity in the structure of the microalgae population was promoted by the environmental and operational conditions imposed.

Collaborating to Compete: Blood Profiling Atlas in Cancer (BloodPAC) Consortium

The cancer community understands the value of blood profiling measurements in assessing and monitoring cancer. We describe an effort among academic, government, biotechnology, diagnostic, and pharmaceutical companies called the Blood Profiling Atlas in Cancer (BloodPAC) Project. BloodPAC will aggregate, make freely available, and harmonize for further analyses, raw datasets, relevant associated clinical data (e.g., clinical diagnosis, treatment history, and outcomes), and sample preparation and handling protocols to accelerate the development of blood profiling assays.

Influence of biogas flow rate on biomass composition during the optimization of biogas upgrading in microalgal-bacterial processes

The influence of biogas flow rate (0, 0.3, 0.6, and 1.2 m(3) m(-2) h(-1)) on the elemental and macromolecular composition of the algal-bacterial biomass produced from biogas upgrading in a 180 L photobioreactor interconnected to a 2.5 L external bubbled absorption column was investigated using diluted anaerobically digested vinasse as cultivation medium. The influence of the external liquid recirculation/biogas ratio (0.5 < L/G < 67) on the removal of CO2 and H2S, and on the concentrations of O2 and N2 in the upgraded biogas, was also evaluated. A L/G ratio of 10 was considered optimum to support CO2 and H2S removals of 80% and 100%, respectively, at all biogas flow rates tested. Biomass productivity increased at increasing biogas flow rate, with a maximum of 12 ± 1 g m(-2) d(-1) at 1.2 m(3) m(-2) h(-1), while the C, N, and P biomass content remained constant at 49 ± 2%, 9 ± 0%, and 1 ± 0%, respectively, over the 175 days of experimentation. The high carbohydrate contents (60-76%), inversely correlated to biogas flow rates, would allow the production of ≈100 L of ethanol per 1000 m(3) of biogas upgraded under a biorefinery process approach.

Carbon and nutrient removal from centrates and domestic wastewater using algal-bacterial biofilm bioreactors

The mechanisms of carbon and nutrient removal in an open algal-bacterial biofilm reactor and an open bacterial biofilm reactor were comparatively evaluated during the treatment of centrates and domestic wastewater. Comparable carbon removals (>80%) were recorded in both bioreactors, despite the algal-bacterial biofilm supported twice higher nutrient removals than the bacterial biofilm. The main carbon and nitrogen removal mechanisms in the algal-bacterial photobioreactor were assimilation into algal biomass and stripping, while stripping accounted for most carbon and nitrogen removal in the bacterial biofilm. Phosphorus was removed by assimilation into algal-bacterial biomass while no effective phosphorous removal was observed in the bacterial biofilm. Carbon, nitrogen and phosphorus removals of 91 ± 3%, 70 ± 8% and 85 ± 9%, respectively, were recorded in the algal-bacterial bioreactor at 10d of hydraulic retention time when treating domestic wastewater. However, the high water footprint recorded (0.5-6.7 Lm(-2)d(-1)) could eventually compromise the environmental sustainability of this microalgae-based technology.

A phase II study of once-daily dasatinib for patients with castration-resistant prostate cancer (CRPC) (CA180085)

5147

Background: Dasatinib is a potent oral SRC family kinase inhibitor that also inhibits c-KIT and PDGFR in vitro. The anti-proliferative/anti-metastatic activity as well as osteoclast inhibitory function of dasatinib in pre-clinical models supports its potential as a targeted therapy for prostate cancer. Previously we presented results on BID dosing of dasatinib in the treatment of CRPC (ASCO. 2008 Abstract 5156). A second group of patients (pts) was enrolled to investigate the activity, safety and bone effects of 100 mg once daily dosing. Methods: Male pts with progressive metastatic CRPC, rising PSA, castrate levels of testosterone (< 50 ng/dL) and no prior chemotherapy were enrolled. Dasatinib dose was 100 mg QD. Continuation of bisphosphonates was permitted. Primary endpoint was a composite of: PSA responses, bone scans and disease control by RECIST. Urinary N-telopeptide (uNTX) and bone alkaline phosphatase (BAP) were determined Q 4-weeks as indicators of bone metabolism. Results: 47 pts were treated (median treatment duration was 2.3 months). 11 patients were evaluable by RECIST; of these 64% achieved SD. The composite response rate was (8/47) 17%. Of 22 pts with bone scans, 50% were stable at 12 weeks and 3/9 (33%) were stable at 24 weeks. A prolonged PSA doubling time was observed in 32 of 39 pts (82%), including one pt with a PSA response. Of the pts with evaluable bone markers, including those who continued on bisphosphonate therapy, 20/41 (49%) had a ≥ 35% decrease in uNTX and 21/42 (50%) had a decrease from baseline in BAP. Grade 3/4 adverse events (AEs) were experienced by 13% of pts (diarrhea, asthenia, and pleural effusion [n=1]). Grade 1/2 AEs (≥ 15% of pts) were diarrhea, nausea, headache, fatigue, asthenia, anorexia and dyspnea. Conclusions: Fewer and less severe AEs were observed in all categories for the QD dosing group compared to the previously reported BID dosing cohort. In addition, preliminary clinical activity (tumor and PSA response; decreasing bone turnover [uNTX, BAP]), is now confirmed to be similar in pts treated with 100mg QD and BID dosing. These data support the relevance of further studies of dasatinib in metastatic CRPC.

[Table: see text]

Phase II trial of ABT-869 in advanced renal cell cancer (RCC) after sunitinib failure: Efficacy and safety results

5036

Background: ABT-869 is a novel, orally active and potent inhibitor of all VEGF and PDGF receptor tyrosine kinases. Results from a phase I study suggested antitumor activity in advanced solid tumors including RCC. The recommended dose for phase II investigation was 0.25 mg/kg (maximum 25 mg) daily. Methods: We conducted an open-label, multicenter phase II trial of oral ABT-869 in advanced RCC. Eligibility criteria included progressive disease (PD) within 100 days of enrollment after at least 2 cycles of sunitinib, prior nephrectomy, and adequate organ function. The primary endpoint was objective response rate (ORR) per RECIST by central imaging. Secondary endpoints were best response, time to progression (TTP), progression free survival (PFS), and overall survival (OS). Safety was assessed by NCI-CTCAE, v3.0. Results: 53 patients (pts, median age, 61 y [range, 40–80]; clear-cell histology [41 pts]; median number of prior therapies, 2 [range, 1–4]) were enrolled from 8/07 to 10/08. All pts were previously treated with sunitinib, and additional prior treatments included cytokine (19%), sorafenib (15%), temsirolimus (4%), and bevacizumab (4%). Preliminary efficacy data are shown in the Table below. Median TTP was 4.9 mos [95% CI: 3.5–6.8] per central imaging. Median OS is not estimable. The most common adverse events (AEs) were diarrhea (78%), fatigue (67%), hypertension (53%), nausea (51%) and vomiting (39%). AEs ≥ grade 3 included hypertension (24%), fatigue (18%), diarrhea (14%) and hand-foot syndrome (14%). 39 pts required dose reductions. Of the 20 pts who have discontinued therapy at the time of this analysis, 16 were due to PD, 3 due to AEs (1 hemoptysis, 1 fatigue, 1 fatigue/hypertension) and 1 withdrew consent. The remaining 33 pts continue protocol treatment, and updated results will be presented. Conclusions: ABT-869 has activity in RCC after sunitinib failure. The dose will be optimized for future studies.

[Table: see text]

[Table: see text]

Dasatinib and docetaxel combination treatment for patients with castration-resistant progressive prostate cancer: A phase I/II study (CA180086)

5061

Background: Dasatinib, a potent inhibitor of SRC family kinases, inhibits in vitro prostate cancer cell proliferation and migration. Consistent with those findings are the clinical observations that osteoclast activity and bone turnover are downregulated in patients treated with dasatinib. We report promising preliminary results of dasatinib in combination with docetaxel (D) for treatment of metastatic castration-resistant prostate cancer (CRPC). Methods: Male pts with progressive CRPC and castrate levels of testosterone (≤50 ng/dL) requiring chemotherapy were enrolled. Escalating doses of dasatinib (50–120 mg QD) and D (60–75 mg/m2 Q 21 days) were evaluated (n = 16) followed by enrollment of 30 pts at the phase 2-selected dose (100 mg dasatinib QD + D at 75 mg/m2 Q 21 days). Continuation of bisphosphonates was permitted; anti-androgens were discontinued. Primary endpoint (Ph. 2) was to determine drug-drug interactions. Secondary endpoints were: changes in PSA, bone scans and tumor size, bone metabolism [urinary N-telopeptide (uNTX) and bone alkaline phosphatase (BAP)] and PK. Results: 46 pts were treated with 28 pts still on therapy. Median treatment duration (n = 18, pts off study) was 4.2 months (0.13–9.63). Preliminary analysis showed no interaction between dasatinib and D. PSA response was seen in 13/32 (41%) pts, clinical benefit (PR + SD) for RECIST-evaluable pts was 21/21, [7 PR, 5 uPR and 4 SD (at ≥21 wks) and 5 SD at ≥6 wk)]. Of 31 pts with bone scans, 30 patients had a best response of either improved (32%) or stable (65%) at ≥6 weeks. For pts with measurable bone markers levels, 12/26 (46%) had a ≥35% decrease in uNTX and 17/24 (71%) had a decrease in BAP from baseline. 6 of 42 pts experienced ≥ grade 3 adverse events (AEs), including fatigue, myelosuppression and pleural effusion (n = 1). Most common grade 1/2 AEs were fatigue, dysgeusia, GI, and skin disorders. Conclusions: Dasatinib and D at doses up to 120 mg QD and 75 mg/m2 are safe with manageable toxicities and no drug-drug interactions. These data confirm the antitumor and antiosteoclast activity of dasatinib in combination with D and serve as the basis for the ongoing phase III study of this combination.

[Table: see text]

Progesterone metabolism during storage of blood samples from Gyr cattle: Effects of anticoagulant, time and temperature of incubation

Ten Gyr cows with a functional corpus luteum were used to evaluate the effects of time and temperature of incubation of blood samples on progesterone (P4) concentrations detected in plasma or serum. From each cow, a blood sample was collected into a flask containing no anticoagulant, another into an heparinized flask and a third into a flask containing sodium fluoride. The blood from each flask was divided into 46 aliquots. One of them was centrifuged within 5 min of collection. The remaining 45 aliquots were divided into three groups and kept at three different temperatures: 4 degrees C, 17 degrees C, or 37 degrees C. For each anticoagulant, aliquots from every cow and incubation temperature were centrifuged every 30 min for 6 h, and then at 8, 12 and 24 h. Plasma or serum were separated immediately after centrifugation and were kept frozen at -20 degrees C until assayed for progesterone. The mean initial concentration of P4 in serum (8.3 ng/ml) significantly diminished (P<0.05) to 6.7 ng/ml after 5 h of incubation at 4 degrees C, 3 h at 17 degrees C, or 2 h at 37 degrees C. In plasma from heparinized blood the initial concentration (7.8 ng/ml) declined significantly after 6 h of incubation at 4 degrees C, 2 h at 17 degrees C, or 1 h at 37 degrees C. Sodium fluoride used as anticoagulant prevented the degradation of P4 since the initial concentration of P4 (6.7 ng/ml) never declined during incubation at either 4 degrees C or 37 degrees C; the only significant reduction occurred after 24 h of incubation at 17 degrees C.

Evaluation of the incorporation of GnRH into a superovulatory regimen for Zebu cattle

The objective of this study was to evaluate the utilization of gonadotropin releasing hormone (GnRH) as part of a superovulatory regimen for Zebu cattle. Forty Zebu cows were superovulated with 40 mg of follicle stimulating hormone-pituitary (FSH-P) divided in eight fractions of 5 mg injected at 12-h intervals. Luteolysis was induced with 15 mg of luprostiol injected at 48 h after the first injection of FSH-P. Half of the animals were injected with 200 ug of GnRH 3 h after the onset of standing estrus. The other 20 animals were not injected with GnRH. All the cows were inseminated three times at 12-h intervals, starting at the time of standing estrus. Embryos were recovered nonsurgically 7 d after the last insemination. Palpation per rectum performed immediately after collection of the embryos did not show differences in the number of corpora lutea between groups (P > 0.05). Likewise, there were no significant differences between treatments with respect to the total number of embryos plus ova, total number of embryos, or the number of transferable embryos recovered (P>0.05). The number of blastocysts, morulae, degenerated morulae and unfertilized ova was similar for the two groups. It is concluded that the incorporation of GnRH into a part of the superovulatory treatment for Zebu cattle does not improve the results of such treatment.