Publications by authors named "Zettler J"

Background: Intratumoral (IT) delivery of toll-like receptor (TLR) agonists has shown encouraging anti-tumor benefit in preclinical and early clinical studies. However, IT delivery of TLR agonists may lead to rapid effusion from the tumor microenvironment (TME), potentially limiting the duration of local inflammation and increasing the risk of systemic adverse events.

Methods: To address these limitations, TransCon TLR7/8 Agonist-an investigational sustained-release prodrug of resiquimod that uses a TransCon linker and hydrogel technology to achieve sustained and predictable IT release of resiquimod-was developed.

View Article and Find Full Text PDF

Background: Recombinant interleukin-2 (IL-2, aldesleukin) is an approved cancer immunotherapy but causes severe toxicities including cytokine storm and vascular leak syndrome (VLS). IL-2 promotes antitumor function of IL-2Rβ/γ natural killer (NK) cells and CD8, CD4 and gamma delta (γδ) T cells. However, IL-2 also potently activates immunosuppressive IL-2Rα regulatory T cells (Tregs) and IL-2Rα eosinophils and endothelial cells, which may promote VLS.

View Article and Find Full Text PDF

Several of the key issues of planar (Al,Ga)N-based deep-ultraviolet light-emitting diodes could potentially be overcome by utilizing nanowire heterostructures, exhibiting high structural perfection, and improved light extraction. Here, we study the spontaneous emission of GaN/(Al,Ga)N nanowire ensembles grown on Si(111) by plasma-assisted molecular beam epitaxy. The nanowires contain single GaN quantum disks embedded in long (Al,Ga)N nanowire segments essential for efficient light extraction.

View Article and Find Full Text PDF

Hypoparathyroidism (HP) is a condition of parathyroid hormone (PTH) deficiency leading to abnormal calcium and phosphate metabolism. The mainstay of therapy consists of vitamin D and calcium supplements, as well as adjunct Natpara (PTH(1-84)). However, neither therapy optimally controls urinary calcium (uCa) or significantly reduces the incidence of hypercalcemia and hypocalcemia.

View Article and Find Full Text PDF

TransCon CNP is a C-type natriuretic peptide (CNP-38) conjugated via a cleavable linker to a polyethylene glycol carrier molecule, designed to provide sustained systemic CNP levels upon weekly subcutaneous administration. TransCon CNP is in clinical development for the treatment of comorbidities associated with achondroplasia. In both mice and cynomolgus monkeys, sustained exposure to CNP via TransCon CNP was more efficacious in stimulating bone growth than intermittent CNP exposure.

View Article and Find Full Text PDF

In semiconductor quantum-wire heterostructures, interface roughness leads to exciton localization and to a radiative decay rate much smaller than that expected for structures with flat interfaces. Here, we uncover the electronic and optical properties of the one-dimensional extended defects that form at the intersection between stacking faults and inversion domain boundaries in GaN nanowires. We show that they act as crystal-phase quantum wires, a novel one-dimensional quantum system with atomically flat interfaces.

View Article and Find Full Text PDF

In 2012, the orchid mealy bug Pseudococcus microcirculus was first detected in situ in North America's more diverse orchid region, the Big Cypress Basin (Collier Co FL). A follow-up survey showed that the mealy bug is more widespread and found on epiphytic orchids in two locations, in both the Fakahatchee Strand State Preserve (sites B and F) and the Florida Panther National Wildlife Refuge (sites M and C). There, we collected mealy bugs (n = 54) from 35 orchid individuals and screened allelic variation at seven microsatellite loci.

View Article and Find Full Text PDF

The α',β'-epoxyketone moiety of proteasome inhibitors confers high binding specificity to the N-terminal threonine in catalytic proteasome β-subunits. We recently identified the epoxomicin and eponemycin biosynthetic gene clusters and have now conducted isotope-enriched precursor feeding studies and comprehensive gene deletion experiments to shed further light on their biosynthetic pathways. Leucine and two methyl groups from S-adenosylmethionine were readily incorporated into the epoxyketone warhead, suggesting decarboxylation of the thioester intermediate.

View Article and Find Full Text PDF

The realization of semiconductor structures with stable excitons at room temperature is crucial for the development of excitonics and polaritonics. Quantum confinement has commonly been employed for enhancing excitonic effects in semiconductor heterostructures. Dielectric confinement, which gives rises to much stronger enhancement, has proven to be more difficult to achieve because of the rapid nonradiative surface/interface recombination in hybrid dielectric-semiconductor structures.

View Article and Find Full Text PDF

Aminocoumarins are potent antibiotics belonging to a relatively small group of secondary metabolites produced by actinomycetes. Genome mining of Catenulispora acidiphila has recently led to the discovery of a gene cluster responsible for biosynthesis of novel aminocoumarins, cacibiocins. However, regulation of the expression of this novel gene cluster has not yet been analyzed.

View Article and Find Full Text PDF

We investigate the influence of modified growth conditions during the spontaneous formation of GaN nanowires (NWs) on Si(111) in plasma-assisted molecular beam epitaxy. We find that a two-step growth approach, where the substrate temperature is increased during the nucleation stage, is an efficient method to gain control over the area coverage, average diameter, and coalescence degree of GaN NW ensembles. Furthermore, we also demonstrate that the growth conditions employed during the incubation time that precedes nanowire nucleation do not influence the properties of the final nanowire ensemble.

View Article and Find Full Text PDF

We use line-of-sight quadrupole mass spectrometry to monitor the spontaneous formation of GaN nanowires on Si during molecular beam epitaxy. We find that the temporal evolution of nanowire ensembles is well described by a double logistic function. The analysis of the temporal evolution of nanowire ensembles, prepared under a wide variety of growth conditions, allows us to construct a growth diagram that can be used to predict the average delay time that precedes nanowire formation.

View Article and Find Full Text PDF

Genome mining led to the discovery of a novel aminocoumarin gene cluster in the rare actinomycete Catenulispora acidiphila DSM 44928. Sequence analysis revealed the presence of genes putatively involved in export/resistance, regulation, and biosynthesis of the aminocoumarin moiety and its halogenation, as well as several genes with so far unknown function. Two new aminocoumarins, cacibiocin A and B, were identified in the culture broth of C.

View Article and Find Full Text PDF

The epoxyketone proteasome inhibitors are an established class of therapeutic agents for the treatment of cancer. Their unique α',β'-epoxyketone pharmacophore allows binding to the catalytic β-subunits of the proteasome with extraordinary specificity. Here, we report the characterization of the first gene clusters for the biosynthesis of natural peptidyl-epoxyketones.

View Article and Find Full Text PDF

Split intein enabled protein trans-splicing (PTS) is a powerful method for the ligation of two protein fragments, thereby paving the way for various protein modification or protein function control applications. PTS activity is strongly influenced by the amino acids directly flanking the splice junctions. However, to date no reliable prediction can be made whether or not a split intein is active in a particular foreign extein context.

View Article and Find Full Text PDF

Phytosanitary irradiation (PI) treatments are promising measures to overcome quarantine barriers to trade and are currently used in several countries. Although PI has advantages compared with other treatments one disadvantage bedevils research, approval, and application: organisms may remain alive after importation. Although this does not preclude their use as a phytosanitary treatment, it does leave the treatment without an independent verification of efficacy and places a greater burden for assuring quarantine security on the research supporting the treatment.

View Article and Find Full Text PDF

Nonribosomal peptide synthetases serve as multidomain protein templates for producing a wealth of pharmaceutically important natural products. For the correct assembly of the desired natural product the interactions between the different catalytic centres and the reaction intermediates bound to the peptidyl carrier protein must be precisely controlled at spatial and temporal levels. We have investigated the interplay between the adenylation (A) domain and the peptidyl carrier protein in the gramicidin S synthetase I (EC 5.

View Article and Find Full Text PDF

Industry concerns over insect resistance, regulatory action, and the needs of organic processors have renewed interest in nonchemical alternative postharvest treatments to fumigants used for California tree nuts. The development of inexpensive polyvinyl chloride containers capable of holding low pressures has increased the practicality of vacuum treatments for durable commodities such as tree nuts. To develop vacuum treatment protocols, we determined the relative tolerance to vacuum (50 mmHg) at 25 and 30 degrees C of different life stages of three postharvest pests of tree nuts: codling moth, Cydia pomonella (L.

View Article and Find Full Text PDF

Protein splicing is an autocatalytic reaction in which an internal protein domain, the intein, excises itself out of a precursor protein and concomitantly links the two flanking sequences, the exteins, with a native peptide bond. In split inteins, the intein domain is divided into two parts that undergo fragment association followed by protein splicing in trans. Thus, the extein sequences joined in the process originate from two separate molecules.

View Article and Find Full Text PDF

We have studied the naturally split alpha subunit of the DNA polymerase III (DnaE) intein from Nostoc punctiforme PCC73102 (Npu) using purified proteins and determined an apparent first-order rate constant of (1.1+/-0.2)x10(-2) s(-1) at 37 degrees C.

View Article and Find Full Text PDF

Eggs, crawlers, early nymphs, late nymphs, and adults of the pink hibiscus mealybug, Maconellicoccus hirsutus (Green), were tested for their susceptibility to methyl bromide in 2-h laboratory fumigations at ambient conditions (25 degrees C, 95% RH). Dose-response tests indicated that the egg was the most susceptible life stage with an LC99 of 20.2 mg/liter.

View Article and Find Full Text PDF