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101.
S A Leachman P J Gallagher B P Herring M J McPhaul J T Stull 《The Journal of biological chemistry》1992,267(7):4930-4938
The molecular and biochemical properties of myosin light chain kinases from chicken skeletal and smooth muscle were investigated by recombinant DNA techniques. Deletion of the amino-terminal region of either the smooth or skeletal muscle myosin light chain kinase resulted in a decrease in Vmax with no significant change in Km values for light chain substrates. Skeletal/smooth muscle chimeric kinases were inactive when a 65-residue region amino-terminal of the catalytic core was exchanged between the two forms. Changing alanine 494 to glutamic acid within this region in the chicken skeletal muscle myosin light chain kinase increased the Km values for light chains 10-fold. These results are consistent with the hypothesis that the region amino-terminal of the catalytic core in myosin light chain kinases is involved in light chain recognition. A skeletal muscle kinase which contained the smooth muscle calmodulin binding domain remained regulated by Ca2+/calmodulin. Thus, the calmodulin binding domains of smooth and skeletal muscle myosin light chain kinases share structural elements necessary for regulation. 相似文献
102.
Roess AA Monroe BP Kinzoni EA Gallagher S Ibata SR Badinga N Molouania TM Mabola FS Mombouli JV Carroll DS MacNeil A Benzekri NA Moses C Damon IK Reynolds MG 《PLoS neglected tropical diseases》2011,5(10):e1356
Background
In areas where health resources are limited, community participation in the recognition and reporting of disease hazards is critical for the identification of outbreaks. This is particularly true for zoonotic diseases such as monkeypox that principally affect people living in remote areas with few health services. Here we report the findings of an evaluation measuring the effectiveness of a film-based community outreach program designed to improve the understanding of monkeypox symptoms, transmission and prevention, by residents of the Republic of the Congo (ROC) who are at risk for disease acquisition.Methodology/Principal Findings
During 90 days, monkeypox outreach was conducted for ∼23,860 people in northern ROC. Two hundred seventy-one attendees (selected via a structured sample) were interviewed before and after participating in a small-group outreach session. The proportion of interviewees demonstrating monkeypox-specific knowledge before and after was compared. Significant gains were measured in areas of disease recognition, transmission, and mitigation of risk. The ability to recognize at least one disease symptom and a willingness to take a family member with monkeypox to the hospital increased from 49 and 45% to 95 and 87%, respectively (p<0.001, both). Willingness to deter behaviors associated with zoonotic risk, such as eating the carcass of a primate found dead in the forest, remained fundamentally unchanged however, suggesting additional messaging may be needed.Conclusions/Significance
These results suggest that our current program of film-based educational activities is effective in improving disease-specific knowledge and may encourage individuals to seek out the advice of health workers when monkeypox is suspected. 相似文献103.
Jennifer H. E. Baker Alastair H. Kyle Kirsten L. Bartels Stephen P. Methot Erin J. Flanagan Andrew Balbirnie Jordan D. Cran Andrew I. Minchinton 《PloS one》2013,8(10)
Many cancer research efforts focus on exploiting genetic-level features that may be targeted for therapy. Tissue-level features of the tumour microenvironment also represent useful therapeutic targets. Here we investigate the presence of low oxygen tension and sensitivity to NOS inhibition of tumour vasculature as potential tumour-specific features that may be targeted by hypoxic cytotoxins, a class of therapeutics currently under investigation. We have previously demonstrated that tirapazamine (TPZ) mediates central vascular dysfunction in tumours. TPZ is a hypoxic cytotoxin that is also a competitive inhibitor of NOS. Here we further investigated the vascular-targeting activity of TPZ by combining it with NOS inhibitor L-NNA, or with low oxygen content gas breathing. Tumours were analyzed via multiplex immunohistochemical staining that revealed irreversible loss of perfusion and enhanced tumour cell death when TPZ was combined with either low oxygen or a NOS inhibitor. Tumour growth rate was reduced by TPZ + NOS inhibition, and tumours previously resistant to TPZ-mediated vascular dysfunction were sensitized by low oxygen breathing. Additional mapping analysis suggests that tumours with reduced vascular-associated stroma may have greater sensitivity to these effects. These results indicate that poorly oxygenated tumour vessels, also being abnormally organized and with inadequate smooth muscle, may be successfully targeted for significant anti-cancer effects by inhibition of NOS and hypoxia-activated prodrug toxicity. This strategy illustrates a novel use of hypoxia-activated cytotoxic prodrugs as vascular targeting agents, and also represents a novel mechanism for targeting tumour vessels. 相似文献
104.
Trey K. Sato Mary Tremaine Lucas S. Parreiras Alexander S. Hebert Kevin S. Myers Alan J. Higbee Maria Sardi Sean J. McIlwain Irene M. Ong Rebecca J. Breuer Ragothaman Avanasi Narasimhan Mick A. McGee Quinn Dickinson Alex La Reau Dan Xie Mingyuan Tian Jeff S. Piotrowski Jennifer L. Reed Yaoping Zhang Joshua J. Coon Chris Todd Hittinger Audrey P. Gasch Robert Landick 《PLoS genetics》2016,12(11)
105.
D. E. Zamboulis J. M. Senior P. D. Clegg J. A. Gallagher S. D. Carter P. I. Milner 《Purinergic signalling》2013,9(3):383-393
Purinergic pathways are considered important in pain transmission, and P2X receptors are a key part of this system which has received little attention in the horse. The aim of this study was to identify and characterise the distribution of P2X receptor subtypes in the equine digit and associated vasculature and nervous tissue, including peripheral nerves, dorsal root ganglia and cervical spinal cord, using PCR, Western blot analysis and immunohistochemistry. mRNA signal for most of the tested P2X receptor subunits (P2X1–5, 7) was detected in all sampled equine tissues, whereas P2X6 receptor subunit was predominantly expressed in the dorsal root ganglia and spinal cord. Western blot analysis validated the specificity of P2X1–3, 7 antibodies, and these were used in immunohistochemistry studies. P2X1–3, 7 receptor subunits were found in smooth muscle cells in the palmar digital artery and vein with the exception of the P2X3 subunit that was present only in the vein. However, endothelial cells in the palmar digital artery and vein were positive only for P2X2 and P2X3 receptor subunits. Neurons and nerve fibres in the peripheral and central nervous system were positive for P2X1–3 receptor subunits, whereas glial cells were positive for P2X7 and P2X1 and 2 receptor subunits. This previously unreported distribution of P2X subtypes may suggest important tissue specific roles in physiological and pathological processes. 相似文献
106.
Pei W. Thomas Timothy Spicer Michael Cammarata Jennifer S. Brodbelt Peter Hodder Walter Fast 《Bioorganic & medicinal chemistry》2013,21(11):3138-3146
Due to the global threat of antibiotic resistance mediated by New Delhi metallo-beta-lactamase-1 (NDM-1) and the lack of structurally diverse inhibitors reported for this enzyme, we developed screening and counter-screening assays for manual and automated formats. The manual assay is a trans-well absorbance-based endpoint assay in 96-well plates and has a Z′ factor of 0.8. The automated assay is an epi-absorbance endpoint assay in 384-well plates, has a Z′ factor of ?0.8, good signal/baseline ratios (>3.8), and is likely scalable for high-throughput screening (HTS). A TEM-1-based counter-screen is also presented to eliminate false positives due to assay interference or off-target activities. A pilot screen of a pharmacologically characterized compound library identified two thiol-modifying compounds as authentic NDM-1 inhibitors: p-chloromecuribenzoate (p-CMB) and nitroprusside. Recombinant NDM-1 has one Cys residue that serves as a conserved active-site primary zinc ligand and is selectively modified by p-CMB as confirmed by LC–MS/MS. However a C208D mutation results in an enzyme that maintains almost full lactamase activity, yet is completely resistant to the inhibitor. These results predict that covalent targeting of the conserved active-site Cys residue may have drawbacks as a drug design strategy. 相似文献
107.
108.
Daniel Bello-Gil Beatriz Maestro Jennifer Fonseca Juan M. Feliu Víctor Climent Jesús M. Sanz 《PloS one》2014,9(1)
We have developed a general method for the specific and reversible immobilization of proteins fused to the choline-binding module C-LytA on functionalized graphite electrodes. Graphite electrode surfaces were modified by diazonium chemistry to introduce carboxylic groups that were subsequently used to anchor mixed self-assembled monolayers consisting of N,N-diethylethylenediamine groups, acting as choline analogs, and ethanolamine groups as spacers. The ability of the prepared electrodes to specifically bind C-LytA-tagged recombinant proteins was tested with a C-LytA-β-galactosidase fusion protein. The binding, activity and stability of the immobilized protein was evaluated by electrochemically monitoring the formation of an electroactive product in the enzymatic hydrolysis of the synthetic substrate 4-aminophenyl β-D-galactopyranoside. The hybrid protein was immobilized in an specific and reversible way, while retaining the catalytic activity. Moreover, these functionalized electrodes were shown to be highly stable and reusable. The method developed here can be envisaged as a general, immobilization procedure on the protein biosensor field. 相似文献
109.
110.
Brulc JM Yeoman CJ Wilson MK Berg Miller ME Jeraldo P Jindou S Goldenfeld N Flint HJ Lamed R Borovok I Vodovnik M Nelson KE Bayer EA White BA 《PloS one》2011,6(10):e25329