Ultrasensitive detection of SCCA employing a graphene oxide integrated microfiber ring laser biosensor.

Squamous cell carcinoma antigen (SCCA) is one of the most commonly detected cancer biomarkers for a variety of cancers. In this paper, a microfiber ring laser biosensor with a graphene oxide linking layer for SCCA detection was proposed and experimentally demonstrated. SCCA antibody immobilized on graphene oxide surface binds specifically to SCCA, and induces refractive index variation over the surface of the microfiber biosensor, which leads to a wavelength shift of the microfiber ring laser biosensor.

Cost-Efficiency Optimization Serves as a Conserved Mechanism that Promotes Osteosarcoma in Mammals.

Mutations that reduce the biosynthetic cost of ATP production or increase the gene translation efficiency (tAI) are favorable for rapid cell growth and proliferation and therefore likely to be observed in tumors. Whether the mutations in tumors optimize the trade-off between the ATP biosynthesis cost and gene translation efficiency by increasing the tAI/ATP ratio is currently unknown. We retrieved transcriptome data of normal and osteosarcoma tissue samples from humans and mice and identified tumor-specific mutations in each species by using stringent cutoffs and outgroup information.

An evolutionarily conserved mechanism that amplifies the effect of deleterious mutations in osteosarcoma.

Illustrating the molecular consequence of deleterious mutations is essential for bridging the gap between genotype and phenotype. In the cancer field, differential expression of the two alleles on heterozygous sites could directly reflect the effect of a mutation under certain trans environment. We retrieved transcriptomes of osteosarcoma and normal tissues in human and mouse.

Production of highly efficient cellulase mixtures by genetically exploiting the potentials of Trichoderma reesei endogenous cellulases for hydrolysis of corncob residues.

Background: Trichoderma reesei is one of the most important fungi utilized for cellulase production. However, its cellulase system has been proven to be present in suboptimal ratio for deconstruction of lignocellulosic substrates. Although previous enzymatic optimization studies have acquired different types of in vitro synthetic mixtures for efficient lignocellulose hydrolysis, production of in vivo optimized cellulase mixtures by industrial strains remains one of the obstacles to reduce enzyme cost in the biofuels production from lignocellulosic biomass.

A molasses habitat-derived fungus Aspergillus tubingensis XG21 with high β-fructofuranosidase activity and its potential use for fructooligosaccharides production.

The industrial microorganisms used for fructooligosaccharides (FOS) synthesis are generally fermented with sucrose as carbon source to induce the production of β-fructofuranosidase (FFase) having transfructosylation activity. Consequently, isolation of novel FFase producers from a sucrose-enriched biotope would help improve FOS productivity and reduce the process cost. Here, three fungi isolated from a unique sugarcane molasses habitat were found to possess FFase activity and one of them, XG21, exhibited a high capacity to synthesize FOS.

Drug-to-antibody determination for an antibody-drug-conjugate utilizing cathepsin B digestion coupled with reversed-phase high-pressure liquid chromatography analysis.

Antibody drug conjugates or ADCs are currently being evaluated for their effectiveness as targeted chemotherapeutic agents across the pharmaceutical industry. Due to the complexity arising from the choice of antibody, drug and linker; analytical methods for release and stability testing are required to provide a detailed understanding of both the antibody and the drug during manufacturing and storage. The ADC analyzed in this work consists of a tubulysin drug analogue that is randomly conjugated to lysine residues in a human IgG1 antibody.

Tear-mediated delivery of nanoparticles through transcytosis of the lacrimal gland.

Rapid clearance from the tears presents a formidable obstacle to the delivery of peptide drugs to the eye surface. This impedes therapies for ocular infections, wound healing, and dry-eye disease that affect the vision of millions worldwide. To overcome this challenge, this manuscript explores a novel strategy to reach the ocular surface via receptor-mediated transcytosis across the lacrimal gland (LG), which produces the bulk of human tears.

Biodegradation of elastin-like polypeptide nanoparticles.

Protein polymers are repetitive polypeptides produced by ribosomal biosynthetic pathways; furthermore, they offer emerging opportunities in drug and biopharmaceutical delivery. As for any polymer, biodegradation is one of the most important determinants affecting how a protein polymer can be utilized in the body. This study was designed to characterize the proteolytic biodegradation for a library of protein polymers derived from the human tropoelastin, the Elastin-like polypeptides (ELPs).

A Rab11a-enriched subapical membrane compartment regulates a cytoskeleton-dependent transcytotic pathway in secretory epithelial cells of the lacrimal gland.

Despite observations that the lacrimal gland has been identified as the principal source of dimeric immunoglobulin A (dIgA) in tears, the mechanism used by lacrimal gland acinar cells (LGACs) to transcytose dIgA produced by interstitial plasma cells is not well-characterized. This study identifies a transcytotic pathway in LGACs regulated by Rab11a for polymeric immunoglobulin receptor (pIgR) and dIgA. EGFP-tagged Rab11a expressed in primary LGACs labeled a unique membrane compartment of comparable localization to endogenous Rab11a beneath the apical plasma membrane.

Design and cellular internalization of genetically engineered polypeptide nanoparticles displaying adenovirus knob domain.

Hepatocytes and acinar cells exhibit high-efficiency, fiber-dependent internalization of adenovirus; however, viral capsids have unpredictable immunological effects and are challenging to develop into targeted drug carriers. To exploit this internalization pathway and minimize the use of viral proteins, we developed a simple gene product that self assembles nanoparticles decorated with the knob domain of adenovirus serotype 5 fiber protein. The most significant advantages of this platform include: (i) compatibility with genetic engineering; (ii) no bioconjugate chemistry is required to link fusion proteins to the nanoparticle surface; and (iii) it can direct the reversible assembly of large nanoparticles, which are monodisperse, multivalent, and biodegradable.

Efficient Lewis acid ionic liquid-catalyzed synthesis of the key intermediate of coenzyme Q10 under microwave irradiation.

An efficient synthesis of a valuable intermediate of coenzyme Q(10) by microwave-assisted Lewis acidic ionic liquid (IL)-catalyzed Friedel-Crafts alkylation is reported. The acidity of six [Etpy]BF(4)-based ionic liquids was characterized by means of the FT-IR technique using acetonitrile as a molecular probe. The catalytic activities of these ionic liquids were correlated with their Lewis acidity.

Synthesis, biophysical properties and pharmacokinetics of ultrahigh molecular weight tense and relaxed state polymerized bovine hemoglobins.

Hemoglobin-based oxygen carriers (HBOC) are currently being developed as red blood cell (RBC) substitutes for use in transfusion medicine. Despite significant commercial development, late stage clinical results of polymerized hemoglobin (PolyHb) solutions hamper development. We synthesized two types of PolyHbs with ultrahigh molecular weights: tense (T) state PolyHb (M(W)=16.

Effects of the molecular mass of tense-state polymerized bovine hemoglobin on blood pressure and vasoconstriction.

Despite recent advances in the design of hemoglobin (Hb)-based oxygen carriers (HBOCs), vasoconstriction, presumably caused by nitric oxide (NO) scavenging, vessel wall hyperoxygenation, and/or extravasation, has been identified as the principal road block hampering commercial development of HBOCs. This study was designed to analyze systemic and microvascular responses to the molecular mass and plasma concentration of tense (T)-state polymerized bovine Hb (PolybHb) solutions. Experiments were performed using the hamster window chamber model subjected to successive hypervolemic infusions of T-state PolybHb solutions.

The quaternary structure of tetrameric hemoglobin regulates the oxygen affinity of polymerized hemoglobin.

This study focuses on the effect of the initial quaternary structure of bovine hemoglobin (Hb) on the physical properties of glutaraldehyde polymerized Hb (PolyHb) solutions. Tense (T) state PolyHb was synthesized by maintaining the pO(2) of Hb before and after polymerization at 0 mm Hg. In contrast, relaxed (R) state PolyHb was generated by maintaining the pO(2) of Hb before and after polymerization to >749 mm Hg.

Purification of hemoglobin by tangential flow filtration with diafiltration.

A recent study by Palmer, Sun, and Harris (Biotechnol. Prog., 25:189-199, 2009) demonstrated that tangential flow filtration (TFF) can be used to produce HPLC-grade bovine and human hemoglobin (Hb).

Tangential flow filtration of hemoglobin.

Bovine and human hemoglobin (bHb and hHb, respectively) was purified from bovine and human red blood cells via tangential flow filtration (TFF) in four successive stages. TFF is a fast and simple method to purify Hb from RBCs using filtration through hollow fiber (HF) membranes. Most of the Hb was retained in stage III (100 kDa HF membrane) and displayed methemoglobin levels less than 1%, yielding final concentrations of 318 and 300 mg/mL for bHb and hHb, respectively.

Identical-dual-bandpass sampled fiber Bragg grating and its application to ultranarrow filters.

We have theoretically proposed and experimentally demonstrated a new kind of ultranarrow identical-dual-bandpass sampled fiber Bragg gratings (SFBGs) with a pi phase shift technique. The spacing of two bandpasses of the proposed grating can be flexibly adjusted by changing the sampled period, and any desired spacing can be achieved in principle. An experimental example shows that the transmission peaks of two narrow transmission-band are near 1549.

Site-selective glycosylation of hemoglobin on Cys beta93.

In this work, we describe the synthesis and characterization of a novel glycosylated hemoglobin (Hb) with high oxygen affinity as a potential Hb-based oxygen carrier. Site-selective glycosylation of bovine Hb was achieved by conjugating a lactose derivative to Cys 93 on the beta subunit of Hb. LC-MS analysis indicates that the reaction was quantitative, with no unmodified Hb present in the reaction product.

Tunable multiwavelength fiber laser using a comb filter based on erbium-ytterbium co-doped polarization maintaining fiber loop mirror.

A tunable comb filter based on a fiber loop mirror setup, which incorporates a piece of pumped erbium-ytterbium co-doped polarization maintaining fiber, is newly presented. It is accomplished by controlling the pump power or adjusting a polarization controller in the loop mirror, which results from the fact that the effective birefringence of the erbium-ytterbium co-doped polarization maintaining fiber depends on the pump power and polarization state of the traversing signal. By using the proposed comb filter, a continuously tunable multiwavelength fiber ring laser in the L-band is successfully demonstrated.

Preparation of ultrapure bovine and human hemoglobin by anion exchange chromatography.

Bovine and human hemoglobin (Hb) form the basis for many different types of Hb-based O(2) carriers (HBOCs) ranging from chemically modified Hbs to particle encapsulated Hbs. Hence, the development of a facile purification method for preparing ultrapure Hb is essential for the reliable synthesis and formulation of HBOCs. In this work, we describe a simple process for purifying ultrapure solutions of bovine and human Hb.

Tunable multi-wavelength SOA fiber laser based on a Sagnac loop mirror using an elliptical core side-hole fiber.

We propose and experimentally demonstrate a tunable multi-wavelength SOA fiber laser based on a Sagnac loop mirror using elliptical core side-hole fiber. We fabricated different types of elliptical core side-hole fiber with elliptical or circular cladding shape. The measured modal birefringence of the fabricated fiber was 1.

The temperature sensitivity of Sagnac loop interferometer based on polarization maintaining side-hole fiber.

The temperature sensitivity of modal birefringence (dB/dT) of different types of polarization-maintaining fibers with side holes was measured using a Sagnac loop interferometer. The thermal expansion coefficient can be varied by controlling the amount of germanium doped in the core region. Using this method, dB/dT could be made higher (~10(-7)/ degrees C) than that of standard PMFs (~10(-8)/ degrees C) or comparable to that of standard PMFs (~10(-9)/ degrees C).

Novel biporous polymeric stationary phase for high-speed protein chromatography.

A novel rigid biporous bead (BiPB) had been fabricated by double emulsification to prepare a (w/o)/w emulsion and a subsequent polymerization. The polymerization of monomers, glycidyl methacrylate and ethylene glycol dimethacrylate, was initiated with benzoin ethyl ether by ultraviolet irradiation. The BiPB with an average diameter of 42.