The dynamics of the metabolism of acetate and bicarbonate associated with use of hemodialysates in the ABChD trial: a phase IV, prospective, single center, single blind, randomized, cross-over, two week investigation.

BACKGROUND: In the United States, hemodialysis (HD) is generally performed via a bicarbonate dialysate. It is not known if small amounts of acid used in dialysate to buffer the bicarbonate can meaningfully contribute to overall buffering administered during HD. We aimed to investigate the metabolism of acetate with use of two different acid buffer concentrates and determine if it effects blood bicarbonate concentrations in HD patients. METHODS: The Acid-Base Composition with use of hemoDialysates (ABChD) trial was a Phase IV, prospective, single blind, randomized, cross-over, 2 week investigation of peridialytic dynamics of acetate and bicarbonate associated with use of acid buffer concentrates. Eleven prevalent HD patients participated from November 2014 to February 2015. Patients received two HD treatments, with NaturaLyte® and GranuFlo® acid concentrates containing 4 and 8 mEq/L of acetate, respectively. Dialysate order was chosen in a random fashion. The endpoint was to characterize the dynamics of acetate received and metabolized during hemodialysis, and how it effects overall bicarbonate concentrations in the blood and dialysate. Acetate and bicarbonate concentrations were assessed before, at 8 time points during, and 6 time points after the completion of HD. RESULTS: Data from 20 HD treatments for 11 patients (10 NaturaLyte® and 10 GranuFlo®) was analyzed. Cumulative trajectories of arterialized acetate were unique between NaturaLyte® and GranuFlo® (p = 0.003), yet individual time points demonstrated overlap without remarkable differences. Arterialized and venous blood bicarbonate concentrations were similar at HD initiation, but by 240 min into dialysis, mean arterialized bicarbonate concentrations were 30.2 (SD ± 4.16) mEq/L in GranuFlo® and 28.8 (SD ± 4.26) mEq/L in NaturaLyte®. Regardless of acid buffer concentrate, arterial blood bicarbonate was primarily dictated by the prescribed bicarbonate level. Subjects tolerated HD with both acid buffer concentrates without experiencing any related adverse events. CONCLUSIONS: A small fraction of acetate was delivered to HD patients with use of NaturaLyte® and GranuFlo® acid buffers; the majority of acetate received was observed to be rapidly metabolized and cleared from the circulation. Blood bicarbonate concentrations appear to be determined mainly by the prescribed concentration of bicarbonate. TRIAL REGISTRATION: This trial was registered on ClinicalTrials.gov on 11 Dec 2014 ( NCT02334267 ).

The use of polysulfated polysaccharides heparin like compounds, glycosaminoglycans and Vitamin B17 as a possible treatment for prostate cancer.

Prostate cancer is impacting many men globally. It is a disease that has no effective treatment is available in the market. The understanding of the biophysical and biochemical aspects of the disease and the mechanism that allow it to metastasize is key to finding an effect treatment. Maintenance or pretreatment drug as well as a post treatment drug can be effective to avoid or delay the disease from appearing. The polysaccharides and monosaccharides polymers combined with vitamins can be the ingredient to developing the treatment. There are many evidences that investigators examined the individual components of the therapy proposed but never a combination of all these therapies. The one item that is not discussed is how to formulate the ingredient into an effective form which is a proprietary work being conducted currently. Nevertheless, the hypothesis seems reasonable to us and worth sharing with the scientific community.

Use of an on-line imprinted polymer pre-column, for the liquid chromatographic-UV absorbance determination of carbaryl and its metabolite in complex matrices.

A carbaryl and 1-naphtol molecular imprinted polymers (MIP1 and MIP 2, respectively) were prepared using suspension polymerization and tested for selective and reversible binding to carbaryl and 1-naphtol, respectively. In the suspension polymerization technique used, polymers of methacrylic acid (MAA), highly cross-linked with ethylene dimethacrylate, provide a specific binding sites for the carbaryl molecule and its metabolite when using it as a template to be removed after polymerization. The molecular imprinted polymer with a particle size of approximately 5 microm were isolated and packed into a pre-column (50 mm x 4.6 mm id) that was used to isolate carbaryl and its metabolite from complex matrices injected on a high performance liquid chromatography system using ultra-violet detection without extensive sample preparation and clean up. The HPLC method had a detection limit of 1.00 ng/mL and a linear response (r2 > 0.98) over the concentration range of 1.00-10.0 ng/mL.

The development, optimization and validation of an ELISA bioanalytical method for the determination of Cetuximab in human serum.

Cetuximab is a chimeric IgG1 monoclonal antibody that inhibits epidermal growth factor receptor (EGFR). Additionally, Cetuximab, used in combination therapy, potentiates the effects of chemotherapy and radiation therapy in eradicating well-established tumors. Recently, a combination of Cetuximab and newly developed chemotherapeutic candidate drugs is being investigated for use as a new-generation chemotherapy cocktail. Therefore, there is an increasing need for a highly selective immunoassay to detect Cetuximab at low concentration levels in human serum. We report a newly developed ELISA that is validated under FDA-GLP regulations for the detection of Cetuximab. It is highly selective and achieves a lower limit of quantitation of 0.31 µg/mL. We have validated a selective and sensitive bioanalytical method.

Application of an in-line imprinted polymer column in a potentiometric flow-injection chemical sensor to the determination of the carbamate pesticide carbaryl in complex biological matrices.

A flow-injection biosensor-like system based on a nonenzymatic approach has been developed to determine the carbamate pesticide carbaryl in complex biological samples without lengthy and expensive extraction steps. Molecularly imprinted polymeric beads were used to immobilize carbaryl from biological samples. pH variation permitted the elution of carbaryl from the binding cavity to the flow cell. A pH electrode was used to detect changes in the charge of carbaryl in the sample solution resulting from the protonation and deprotonation of the molecule over different pH ranges. At pH 2.0, the secondary amine group is protonated, giving a (+1) charge to the carbaryl molecule. At pH 8.0, the ionized carbaryl loses a proton to become neutral, changing the local pH of the flow cell. The pH change at the flow cell generated by the deprotonation of carbaryl ion in alkaline medium was used to determine the carbaryl concentration. Parameters influencing the performance of the system were optimized for use in the detection procedure. The validated biosensor-like system had a carbaryl detection limit of 10.0 microg/mL and a response that was linear (r2>0.98) over the concentration range of 10.0-00 microg/mL.