Epitope Mapping Using Yeast Display and Next Generation Sequencing.

Monoclonal antibodies are the largest class of therapeutic proteins due in part to their ability to bind an antigen with a high degree of affinity and specificity. A precise determination of their epitope is important for gaining insights into their therapeutic mechanism of action and to help differentiate antibodies that bind the same antigen. Here, we describe a method to precisely and efficiently map the epitopes of multiple antibodies in parallel over the course of just several weeks.

Productive common light chain libraries yield diverse panels of high affinity bispecific antibodies.

The commercial success of bispecific antibodies generally has been hindered by the complexities associated with generating appropriate molecules for both research scale and large scale manufacturing purposes. Bispecific IgG (BsIgG) based on two antibodies that use an identical common light chain can be combined with a minimal set of Fc mutations to drive heavy chain heterodimerization in order to address these challenges. However, the facile generation of common light chain antibodies with properties similar to traditional monoclonal antibodies has not been demonstrated and they have only been used sparingly.

Lasso Peptide Biosynthetic Protein LarB1 Binds Both Leader and Core Peptide Regions of the Precursor Protein LarA.

Lasso peptides are a member of the superclass of ribosomally synthesized and posttranslationally modified peptides (RiPPs). Like all RiPPs, lasso peptides are derived from a gene-encoded precursor protein. The biosynthesis of lasso peptides requires two enzymatic activities: proteolytic cleavage between the leader peptide and the core peptide in the precursor protein, accomplished by the B enzymes, and ATP-dependent isopeptide bond formation, accomplished by the C enzymes.

Renal registry in Hong Kong-the first 20 years.

Renal Registry was started by the Hospital Authority (HA) in Hong Kong in 1995. It is an online system developed by HA. It collects all patients under care in HA, which is about 90-95 % of all requiring renal replacement therapy (RRT) in Hong Kong.

Precise and efficient antibody epitope determination through library design, yeast display and next-generation sequencing.

The ability of antibodies to bind an antigen with a high degree of affinity and specificity has led them to become the largest and fastest growing class of therapeutic proteins. Clearly identifying the epitope at which they bind their cognate antigen provides insight into their mechanism of action and helps differentiate antibodies that bind the same antigen. Here, we describe a method to precisely and efficiently map the epitopes of a panel of antibodies in parallel over the course of several weeks.

Trends in prevalence and mortality of dementia in elderly Hong Kong population: projections, disease burden, and implications for long-term care.

Background. We describe the trends in prevalence and mortality of dementia among older people in Hong Kong over time. Projections of the number of older people with dementia through 2039 and estimation of the disease burden are also included.

Construction of a single polypeptide that matures and exports the lasso peptide microcin J25.

Roped in: The lasso peptide microcin J25 (MccJ25) is matured by two enzymes and is exported by a putative ABC transporter. We probed the function of the maturation enzymes using mutagenesis. We demonstrate that fusions of the enzymes with intervening linkers can produce MccJ25.

Optimized fabrication of Ca-P/PHBV nanocomposite scaffolds via selective laser sintering for bone tissue engineering.

Biomaterials for scaffolds and scaffold fabrication techniques are two key elements in scaffold-based tissue engineering. Nanocomposites that consist of biodegradable polymers and osteoconductive bioceramic nanoparticles and advanced scaffold manufacturing techniques, such as rapid prototyping (RP) technologies, have attracted much attention for developing new bone tissue engineering strategies. In the current study, poly(hydroxybutyrate-co-hydroxyvalerate) (PHBV) microspheres and calcium phosphate (Ca-P)/PHBV nanocomposite microspheres were fabricated using the oil-in-water (O/W) and solid-in-oil-in-water (S/O/W) emulsion solvent evaporation methods.

Computational design of the lasso peptide antibiotic microcin J25.

Microcin J25 (MccJ25) is a 21 amino acid (aa) ribosomally synthesized antimicrobial peptide with an unusual structure in which the eight N-terminal residues form a covalently cyclized macrolactam ring through which the remaining 13 aa tail is fed. An open question is the extent of sequence space that can occupy such an extraordinary, highly constrained peptide fold. To begin answering this question, here we have undertaken a computational redesign of the MccJ25 peptide using a two-stage sequence selection procedure based on both energy minimization and fold specificity.

Three-dimensional nanocomposite scaffolds fabricated via selective laser sintering for bone tissue engineering.

Bionanocomposites formed by combining biodegradable polymers and nanosized osteoconductive inorganic solids have been regarded as promising biomimetic systems which possess much improved structural and functional properties for bone tissue regeneration. In this study three-dimensional nanocomposite scaffolds based on calcium phosphate (Ca-P)/poly(hydroxybutyrate-co-hydroxyvalerate) (PHBV) and carbonated hydroxyapatite (CHAp)/poly(l-lactic acid) (PLLA) nanocomposite microspheres were successfully fabricated using selective laser sintering, which is a rapid prototyping technology. The sintered scaffolds had controlled material microstructure, totally interconnected porous structure and high porosity.

Strain analysis of maxillary complete denture with three-dimensional finite element method.

Statement Of Problem: The fracture of maxillary complete dentures has been reported as the most common prosthesis failure.

Purpose: The purpose of this study was to evaluate strain distribution in dentures during application of occlusal load with 3-dimensional (3-D) finite element analysis (FEA).

Material And Methods: A maxillary complete denture was converted into a 3-D numerical model by an advanced topometric sensor digitizer (ATOS).

Much of the microcin J25 leader peptide is dispensable.

The antimicrobial peptide microcin J25 (MccJ25) is matured by two enzymes, McjB and McjC, from a 58 amino acid (aa) preprotein, McjA, into its final 21 aa lasso topology. Herein we have investigated the role of the leader peptide of McjA and found that only the eight C-terminal amino acids of this leader peptide are required for maturation of MccJ25. There is a high content of lysine residues in the McjA leader peptide, but herein we also demonstrate that these charged amino acids do not play a major role in the maturation of MccJ25.

Engineered gene clusters for the production of the antimicrobial peptide microcin J25.

Microcin J25 (MccJ25) is an antimicrobial peptide produced by isolates of Escherichia coli with activity against closely related species. Production and export of mature MccJ25 in E. coli requires four genes that are organized on a plasmid-borne cluster in natural producer strains.

Selective laser sintering of porous tissue engineering scaffolds from poly(L: -lactide)/carbonated hydroxyapatite nanocomposite microspheres.

This study focuses on the use of bio-nanocomposite microspheres, consisting of carbonated hydroxyapatite (CHAp) nanospheres within a poly(L: -lactide) (PLLA) matrix, to produce tissue engineering (TE) scaffolds using a modified selective laser sintering (SLS) machine. PLLA microspheres and PLLA/CHAp nanocomposite microspheres were prepared by emulsion techniques. The resultant microspheres had a size range of 5-30 microm, suitable for the SLS process.

Predictors of positive stool culture in adult patients with acute infectious diarrhea.

Stool cultures for bacterial pathogens are often requested for investigation of patients with infectious diarrhea, but the literature reports low yield for this diagnostic test. The identification of clinical predictors of positive stool culture will help the physician in determining the necessity for stool requests. A retrospective study was performed in the setting of an Emergency Department (ED) in Hong Kong, to compare presenting features of adult patients with positive stool culture against those with negative culture.