Prevalence of kidney disease of unknown etiology in agricultural workers, Guatemala.

Objectives: To determine the prevalence of kidney disease of unknown etiology in banana, melon, and tomato workers in north-eastern Guatemala, and to evaluate the usefulness of a cystatin C blood test for early detection of renal disease.

Methods: This was a cross-sectional, farm-based study of 462 agricultural workers conducted from June to September 2021. Epidemiological and demographic characteristics of the workers were collected through a self-administered questionnaire.

PEG-modified biopharmaceuticals.

PEGylation is a process in which one or more units of chemically activated polyethylene glycol reacts with a biomolecule, usually a protein, peptide, small molecule or oligonucleotide, creating a putative new molecular entity possessing physicochemical and physiological characteristics that are distinct from its predecessor molecules. In recent years, PEGylation has been used not only as a drug delivery technology but used also as a drug modification technology to transform existing biopharmaceuticals clinically more efficacious than before their PEGylation. PEGylation bestows several useful properties upon the native molecule, resulting in improved pharmacokinetic and pharmacodynamic properties, which in turn enable the native molecule to achieve maximum clinical potency.

Identification of model peptides as affinity ligands for the purification of humanized monoclonal antibodies by means of phage display.

A proof-of-principle study was initiated to determine whether phage-display technology could be used to identify peptides as leads in the customization of ligands for affinity chromatography and to identify a peptide or peptidomimetic for use as a Protein A alternative in the affinity purification of monoclonal antibodies. The constant region of humanized anti-Tac (HAT), prepared by pepsin digestion and receptor-affinity chromatography, was used as the target for phage display in this study. As such, 20 phage-derived peptide sequences were identified from four rounds of biopanning with two linear phage-display libraries (7-mer, containing 100 copies of 2 x 10(9) sequences and 12-mer, containing 70 copies of 1.

Rational design of a potent, long-lasting form of interferon: a 40 kDa branched polyethylene glycol-conjugated interferon alpha-2a for the treatment of hepatitis C.

A potent, long-lasting form of interferon alpha-2a mono-pegylated with a 40 kilodalton branched poly(ethylene glycol) was designed, synthesized, and characterized. Mono-pegylated interferon alpha-2a was comprised of four major positional isomers involving Lys31, Lys121, Lys131, and Lys134 of interferon. The in vitro anti-viral activity of pegylated interferon alpha-2a was found to be only 7% of the original activity.