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991.
992.
Hu H Armstrong PC Khalil E Chen YC Straub A Li M Soosairajah J Hagemeyer CE Bassler N Huang D Ahrens I Krippner G Gardiner E Peter K 《PloS one》2011,6(4):e19190
Background
Staphylococcus aureus (S. aureus) is a common pathogen capable of causing life-threatening infections. Staphylococcal superantigen-like protein 5 (SSL5) has recently been shown to bind to platelet glycoproteins and induce platelet activation. This study investigates further the interaction between SSL5 and platelet glycoproteins. Moreover, using a glycan discovery approach, we aim to identify potential glycans to therapeutically target this interaction and prevent SSL5-induced effects.Methodology/Principal Findings
In addition to platelet activation experiments, flow cytometry, immunoprecipitation, surface plasmon resonance and a glycan binding array, were used to identify specific SSL5 binding regions and mediators. We independently confirm SSL5 to interact with platelets via GPIbα and identify the sulphated-tyrosine residues as an important region for SSL5 binding. We also identify the novel direct interaction between SSL5 and the platelet collagen receptor GPVI. Together, these receptors offer one mechanistic explanation for the unique functional influences SSL5 exerts on platelets. A role for specific families of platelet glycans in mediating SSL5-platelet interactions was also discovered and used to identify and demonstrate effectiveness of potential glycan based inhibitors in vitro.Conclusions/Significance
These findings further elucidate the functional interactions between SSL5 and platelets, including the novel finding of a role for the GPVI receptor. We demonstrate efficacy of possible glycan-based approaches to inhibit the SSL5-induced platelet activation. Our data warrant further work to prove SSL5-platelet effects in vivo. 相似文献993.
Rawia M. Khalil Ahmed Abdelbary Silvia Kocova El-Arini Mona Basha 《Journal of liposome research》2019,29(2):171-182
Bilosomes were developed in order to investigate their efficacy as nanocarriers for transdermal delivery of Tizanidine HCl (TZN), a skeletal muscle relaxant with low oral bioavailability. Full factorial experimental design consisting of 27 combinations was generated to study the effects of surfactant type, surfactant-to-cholesterol ratio and the amount of bile salt on the entrapment efficiency (EE), the vesicle size (VS) and in vitro dissolution of the TZN-loaded bilosomes. The permeation through the stratum cornea was optimized with the vertical diffusion assembly using excised rat skin. The permeation parameters of the selected bilosomes were compared to the unformulated drug and it was shown that TZN-B24 exhibited the highest enhancement ratio (ER?=?8.8).The optimal formula (TZN-B24) consisting of span 60 in a ratio with cholesterol of 1:1 and 20?mg of bile salt was obtained by employing the desirability function of Design-Expert® software. The mathematical model used for the optimization was validated by comparing the predicted values of the EE (82.3%) and the VS (165.8?nm) with the experimental values of EE?=?84.42% and of VS?=?161.95?nm. TZN-B24 displayed high zeta potential which contributed to its good stability. It was evident from the results of this study that incorporating TZN in bilosomes improved significantly its permeation through the skin barrier and thus bilosomes can offer a potential nanoplatform using the transdermal route to improve the bioavailability of the drug. 相似文献
994.
Hussein Kaddour Jacques Vergne Guy Herve Marie-Christine Maurel 《Biochimica et Biophysica Acta (BBA)/General Subjects》2014
Background
Viroids are the smallest pathogens known to date. They infect plants and cause considerable economic losses. The members of the Avsunviroidae family are known for their capability to form hammerhead ribozymes (HHR) that catalyze self-cleavage during their rolling circle replication.Methods
In vitro inhibition assays, based on the self-cleavage kinetics of the hammerhead ribozyme from a Chrysanthemum chlorotic mottle viroid (CChMVd-HHR) were performed in the presence of various putative inhibitors.Results
Aminated compounds appear to be inhibitors of the self-cleavage activity of the CChMVd HHR. Surprisingly the spermine, a known activator of the autocatalytic activity of another hammerhead ribozyme in the presence or absence of divalent cations, is a potent inhibitor of the CChMVd-HHR with Ki of 17 ± 5 μM. Ruthenium hexamine and TMPyP4 are also efficient inhibitors with Ki of 32 ± 5 μM and IC50 of 177 ± 5 nM, respectively.Conclusions
This study shows that polyamines are inhibitors of the CChMVd-HHR self-cleavage activity, with an efficiency that increases with the number of their amino groups.General significance
This fundamental investigation is of interest in understanding the catalytic activity of HHR as it is now known that HHR are present in the three domains of life including in the human genome. In addition these results emphasize again the remarkable plasticity and adaptability of ribozymes, a property which might have played a role in the early developments of life and must be also of significance nowadays for the multiple functions played by non-coding RNAs. 相似文献995.
Hussein L Rubenwolf S von Stetten F Urban G Zengerle R Krueger M Kerzenmacher S 《Biosensors & bioelectronics》2011,26(10):4133-4138
The redox enzyme laccase from Trametes versicolor efficiently catalyzes the oxygen reduction reaction (ORR) in mediatorless biofuel cell cathodes when adsorbed onto multi-walled carbon nanotubes (MWCNTs). In this work we demonstrate that the fabrication of MWCNTs in form of buckypaper (BP) results in an excellent electrode material for laccase-catalyzed cathodes. BPs are mechanically stable, self-entangling mats with high dispersion of MWCNTs resulting in easy to handle homogeneous layers with highly mesoporous structures and excellent electrical conductivities. All biocathodes have been electrochemically investigated in oxygen-saturated buffer at pH 5 by galvanostatic polarization and potentiodynamic linear sweep voltammetry. Both methods confirm an efficient direct interaction of laccase with BP with a high open circuit potential of 0.882 V vs. normal hydrogen electrode (NHE). The high oxygen reduction performance leads to high current densities of 422±71 μA cm(-2) at a typical cathode potential of 0.744 V vs. NHE. When the current density is normalized to the mass of the electrode material (mass activity), the BP-based film electrodes exhibit a 68-fold higher current density at 0.744 V vs. NHE than electrodes fabricated from the same MWCNTs in a non-dispersed agglomerated form as packed electrodes. This clearly shows that MWCNTs can act more efficiently as cathode when prepared in form of BP. This can be attributed to reduced diffusional mass transfer limitations and enhanced electrical conductivity. BP is thus a very promising material for the construction of mediatorless laccase cathodes for ORR in biofuel cells. In addition we demonstrated that these electrodes exhibit a high tolerance towards glucose, the most common bioanode fuel. 相似文献
996.
Nine eriophyoid mites, including two new species and five new records, from Iran are described and illustrated. They are Aceria acroptiloni Shevchenko & Kacalev, 1974, rec. n. on Rhaponticum repens (L.) Hidalgo (Asteraceae); Aceria anthocoptes (Nalepa, 1892), rec. n. on Cirsium arvense (L.) Scop. (Asteraceae); Aceria lactucae (Canestrini, 1893), rec. n. on Lactuca virosa L. (Asteraceae); Aceria pulicarissp. n. on Pulicaria gnaphalodes (Vent.) Boiss. (Asteraceae); Aceria tosichella Keifer, 1969 on Setaria viridis (L.) Beauv. (Poaceae); Eriophyes rotundae Mohanasundaram, 1983 on Cyperus rotundus L. (Cyperaceae); Aculops maroccensis Keifer, 1972, rec. n. on Mentha piperita L. (Lamiaceae); Aculus medicagersp. n. on Medicago sativa L. (Leguminosae); Tetra lycopersici Xue & Hong, 2005, rec. n. on Solanum nigrum L. (Solanaceae). 相似文献
997.
Summary The binding and uptake of lead by the jejunal, colonic and gallbladder epithelium of guinea pig has been investigated by electron microscopy. Binding occurred rapidly, the most marked by the microvilli was by the jejunum, followed by colon and gallbladder. The tracer was subsequently internalised in small membrane bound vesicles and smooth endoplasmic reticulum. By 30 min, it appeared in multivesicular bodies at all three sites. 相似文献
998.
Hussein MF Aljumaah RS Homeida AM Alhaidary AA Alshaikh MA Gar Elnabi A Mohammed OB Omer SA Macasero WV 《Journal of wildlife diseases》2010,46(4):1165-1171
During March 2009, we evaluated the hemostatic profile and platelet indices of 18 Arabian sand gazelles (Gazella subgutturosa marica) and compared the results with those from humans and camels (Camelus dromedarius). Gazelles and camels had shorter activated partial thromboplastin times, lower proconvertin and higher antihemophilic factor coagulation activity, and plasma fibrinogen levels than humans. Prothrombin time was longer in sand gazelles and shorter in camels than it was in humans. Plasma thromboplastin component, Stuart factor, and plasma thromboplastin antecedent were similar in gazelles, humans, and camels, whereas the platelet count of the sand gazelle was significantly higher than it was for camels and humans. 相似文献
999.
Purpose
The authors present a clinical report of a perforate syringocele diagnosed in a male patient and they review the clinical, radiological and therapeutic aspects of this disease.Case report
A 50-year-old man attended the emergency room with perineal abscess. Computerized Tomography (CT) scan was used to establish the diagnosis. This patient also underwent urethrocystoscopy, sonography and retrograde urethrography.Results
Treatment consisted of open surgical evacuation of the perineal abscess with bladder catheter. Urethrocystoscopy showed a large perforate syringocele in the urethra with no need for endoscopy marsupialization. No recurrence was observed at follow-up at 3 months.Conclusion
Syringocele is a rare malformation which usually is asymptomatic. It can be congenital or acquired and can be classified into four morphological types. The most frequent treatment is endoscopic marsupialization of the syringocèle. Open surgical excision is recommended for complicated syringocèle with abscess or perineal pain. 相似文献1000.
Zdeňka Svobodová Oxana Skoková Habu?tová William D. Hutchison Hany M. Hussein Franti?ek Sehnal 《PloS one》2015,10(6)
Transgenic maize MON88017, expressing the Cry3Bb1 toxin from Bacillus thuringiensis (Bt maize), confers resistance to corn rootworms (Diabrotica spp.) and provides tolerance to the herbicide glyphosate. However, prior to commercialization, substantial assessment of potential effects on non-target organisms within agroecosystems is required. The MON88017 event was therefore evaluated under field conditions in Southern Bohemia in 2009–2011, to detect possible impacts on the above-ground arthropod species. The study compared MON88017, its near-isogenic non-Bt hybrid DK315 (treated or not treated with the soil insecticide Dursban 10G) and two non-Bt reference hybrids (KIPOUS and PR38N86). Each hybrid was grown on five 0.5 ha plots distributed in a 14-ha field with a Latin square design. Semiquantitative ELISA was used to verify Cry3Bb1 toxin levels in the Bt maize. The species spectrum of non-target invertebrates changed during seasons and was affected by weather conditions. The thrips Frankliniella occidentalis was the most abundant species in all three successive years. The next most common species were aphids Rhopalosiphum padi and Metopolophium dirhodum. Frequently observed predators included Orius spp. and several species within the Coccinellidae. Throughout the three-year study, analysis of variance indicated some significant differences (P<0.05). Multivariate analysis showed that the abundance and diversity of plant dwelling insects was similar in maize with the same genetic background, for both Bt (MON88017) and non-Bt (DK315) untreated or insecticide treated. KIPOUS and PR38N86 showed some differences in species abundance relative to the Bt maize and its near-isogenic hybrid. However, the effect of management regime on arthropod community was insignificant and accounted only for a negligible portion of the variability. 相似文献