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1.
Zootaxa ; 4242(2): 255-280, 2017 Mar 10.
Article in English | MEDLINE | ID: mdl-28610183

ABSTRACT

Our objective was to document potential wild pollinating insects in south central Nebraska. This intensively cultivated region is known as the Rainwater Basin and contains some of the most endangered wetland systems in North America. We used blue vane traps to passively collect insects and insect nets to actively collect on flowering plants from April through October in 2014 and 2015. Habitat types included playa wetlands, adjacent mixed and tallgrass prairies, and agricultural fields. Over 112,000 insects were collected; Hymenoptera represented 78% of the total, and the families Apidae and Halictidae comprised 99% of the total melittofauna. Insects from 13 orders were collected, but Hymenoptera, Diptera, and Coleoptera were the most abundant potential pollinators.


Subject(s)
Bees , Wetlands , Animals , Insecta , Nebraska , North America , Pollination
2.
J Med Chem ; 58(17): 6784-802, 2015 Sep 10.
Article in English | MEDLINE | ID: mdl-26288216

ABSTRACT

To realize the medicinal potential of peptide toxins, naturally occurring disulfide-rich peptides, as ion channel antagonists, more efficient pharmaceutical optimization technologies must be developed. Here, we show that the therapeutic properties of multiple cysteine toxin peptides can be rapidly and substantially improved by combining direct chemical strategies with high-throughput electrophysiology. We applied whole-molecule, brute-force, structure-activity analoging to ShK, a peptide toxin from the sea anemone Stichodactyla helianthus that inhibits the voltage-gated potassium ion channel Kv1.3, to effectively discover critical structural changes for 15× selectivity against the closely related neuronal ion channel Kv1.1. Subsequent site-specific polymer conjugation resulted in an exquisitely selective Kv1.3 antagonist (>1000× over Kv1.1) with picomolar functional activity in whole blood and a pharmacokinetic profile suitable for weekly administration in primates. The pharmacological potential of the optimized toxin peptide was demonstrated by potent and sustained inhibition of cytokine secretion from T cells, a therapeutic target for autoimmune diseases, in cynomolgus monkeys.


Subject(s)
Cnidarian Venoms/chemistry , Kv1.3 Potassium Channel/antagonists & inhibitors , Peptides/chemistry , Polyethylene Glycols/chemistry , Animals , CHO Cells , Cnidarian Venoms/pharmacokinetics , Cnidarian Venoms/pharmacology , Cricetulus , Crystallography, X-Ray , Dogs , HEK293 Cells , Humans , Interferon-gamma/blood , Interferon-gamma/metabolism , Interleukin-17/blood , Interleukin-17/metabolism , Interleukin-2/blood , Interleukin-2/metabolism , Kv1.1 Potassium Channel/antagonists & inhibitors , Macaca fascicularis , Male , Mice , Molecular Docking Simulation , Patch-Clamp Techniques , Peptides/pharmacokinetics , Peptides/pharmacology , Rats, Sprague-Dawley , Species Specificity , Stereoisomerism , Structure-Activity Relationship , T-Lymphocytes/drug effects , T-Lymphocytes/metabolism
3.
J Chromatogr A ; 1344: 23-30, 2014 May 30.
Article in English | MEDLINE | ID: mdl-24768125

ABSTRACT

As the pace of drug discovery accelerates there is an increased focus on screening larger numbers of protein therapeutic candidates to identify those that are functionally superior and to assess manufacturability earlier in the process. Although there have been advances toward high throughput (HT) cloning and expression, protein purification is still an area where improvements can be made to conventional techniques. Current methodologies for purification often involve a tradeoff between HT automation or capacity and quality. We present an ÄKTA combined with an autosampler, the ÄKTA-AS, which has the capability of purifying up to 240 samples in two chromatographic dimensions without the need for user intervention. The ÄKTA-AS has been shown to be reliable with sample volumes between 0.5 mL and 100 mL, and the innovative use of a uniquely configured loading valve ensures reliability by efficiently removing air from the system as well as preventing sample cross contamination. Incorporation of a sample pump flush minimizes sample loss and enables recoveries ranging from the low tens of micrograms to milligram quantities of protein. In addition, when used in an affinity capture-buffer exchange format the final samples are formulated in a buffer compatible with most assays without requirement of additional downstream processing. The system is designed to capture samples in 96-well microplate format allowing for seamless integration of downstream HT analytic processes such as microfluidic or HPLC analysis. Most notably, there is minimal operator intervention to operate this system, thereby increasing efficiency, sample consistency and reducing the risk of human error.


Subject(s)
Proteins/isolation & purification , Animals , Antibodies/isolation & purification , Chromatography, Affinity/methods , Humans , Hybridomas/chemistry , Mice , Microchip Analytical Procedures/methods , Robotics
4.
Vision Res ; 42(8): 991-1003, 2002 Apr.
Article in English | MEDLINE | ID: mdl-11934451

ABSTRACT

The formation of global motion patterns depends on the stimulus activation of local motion detectors as well as integrative excitatory and/or inhibitory interactions among the activated detectors. The counterphase row-of-elements [Vis. Res. 34 (1994) 1843] is an ideal stimulus for examining the relationship between the activational/energizing effect of the stimulus and interaction among the activated detectors. This is because the formation of the alternative unidirectional and oscillatory motion patterns for this stimulus requires the stimulation of local motion detectors, but there is no information in the stimulus that specifies either of the patterns. Their formation depends instead on the relative contributions of excitatory and inhibitory interactions to detector activation; the temporal patterns are self-organized. Broadly spread attention affects motion integration by changing the balance of excitatory versus inhibitory interactions, increasing the perception of unidirectional compared with oscillatory motion. (It likewise increases the perception of group compared with element motion for the Ternus stimulus.) There is, however, little if any effect of attentional spread on the luminance contrast required for the perception of single-element motion. The results indicate that the balance of integrative excitatory and/or inhibitory detector interactions can be modified by the perceiver's spread of attention, and further, that such changes need not be mediated by changes in the local, stimulus activation of the detectors.


Subject(s)
Attention/physiology , Motion Perception/physiology , Pattern Recognition, Visual/physiology , Adult , Humans , Lighting , Photic Stimulation/methods
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