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991.
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993.
Angèle Nalbandian Arif A. Khan Ruchi Srivastava Katrina J. Llewellyn Baichang Tan Nora Shukr Yasmin Fazli Virginia E. Kimonis Lbachir BenMohamed 《Inflammation》2017,40(1):21-41
Aberrant activation of the NOD-like receptor (NLR) family, pyrin domain-containing protein 3 (NLRP3) inflammasome, triggers a pathogenic inflammatory response in many inherited neurodegenerative disorders. Inflammation has recently been associated with valosin-containing protein (VCP)-associated diseases, caused by missense mutations in the VCP gene. This prompted us to investigate whether NLRP3 inflammasome plays a role in VCP-associated diseases, which classically affects the muscles, bones, and brain. In this report, we demonstrate (i) an elevated activation of the NLRP3 inflammasome in VCP myoblasts, derived from induced pluripotent stem cells (iPSCs) of VCP patients, which was significantly decreased following in vitro treatment with the MCC950, a potent and specific inhibitor of NLRP3 inflammasome; (ii) a significant increase in the expression of NLRP3, caspase 1, IL-1β, and IL-18 in the quadriceps muscles of VCPR155H/+ heterozygote mice, an experimental mouse model that has many clinical features of human VCP-associated myopathy; (iii) a significant increase of number of IL-1β(+)F4/80(+)Ly6C(+) inflammatory macrophages that infiltrate the muscles of VCPR155H/+ mice; (iv) NLRP3 inflammasome activation and accumulation IL-1β(+)F4/80(+)Ly6C(+) macrophages positively correlated with high expression of TDP-43 and p62/SQSTM1 markers of VCP pathology in damaged muscle; and (v) treatment of VCPR155H/+ mice with MCC950 inhibitor suppressed activation of NLRP3 inflammasome, reduced the F4/80(+)Ly6C(+)IL-1β(+) macrophage infiltrates in the muscle, and significantly ameliorated muscle strength. Together, these results suggest that (i) NLRP3 inflammasome and local IL-1β(+)F4/80(+)Ly6C(+) inflammatory macrophages contribute to pathogenesis of VCP-associated myopathy and (ii) identified MCC950 specific inhibitor of the NLRP3 inflammasome with promising therapeutic potential for the treatment of VCP-associated myopathy. 相似文献
994.
Chawla R Arora R Singh S Sagar RK Sharma RK Kumar R Sharma A Tripathi RP Puri SC Khan HA Shawl AS Sultan P Krishan T Qazi GN 《Evidence-based complementary and alternative medicine : eCAM》2006,3(4):503-511
We have evaluated the effect of variation in aryl-tetralin lignans on the radioprotective properties of Podophyllum hexandrum. Two fractionated fractions of P. hexandrum [methanolic (S1) and chloroform fractions (S2)], with varying aryl-tetralin lignan content were utilized for the present study. The peroxyl ion scavenging potentials of S1 and S2 were found to be comparable [i.e. 45.88% (S1) and 41% (S2)] after a 48 h interval in a time-dependent study, whereas in a 2 h study, S2 exhibited significant (P < 0.05) antioxidant activity in different metal ion + flux states. In the aqueous phase, S2 exhibited non-site-specific reactive oxygen species scavenging activity, i.e. 73.12% inhibition at 500 mug ml(-1). S1 exhibited 58.40 +/- 0.8% inhibition (at 0.025 mug ml(-1)) of the formation of reactive nitrite radicals, comparable to S2 (52.45 +/- 0.825%), and also showed 45.01% site-specific activity (1000 mug ml(-1)), along with significant (P < 0.05) electron donation potential (50-2000 mug ml(-1)) compared to S2. Such activities of S1 could be attributed to the significantly (P < 0.05) higher levels of podophyllotoxin beta-d-glucopyranoside (16.5 times) and demethyl podophyllotoxin glucoside (2.9 times) compared with S2. Together, these findings clearly prove that aryl-tetralin lignan content influences the radiation protective potential of the Podophyllum fractions to a great extent. 相似文献
995.
Absorption enhancers in pulmonary protein delivery. 总被引:7,自引:0,他引:7
Alamdar Hussain John J Arnold Mansoor A Khan Fakhrul Ahsan 《Journal of controlled release》2004,94(1):15-24
Extensive research efforts have been directed towards the systemic administration of therapeutic proteins and poorly absorbed macromolecules via various nontraditional, injection-free administration sites such as the lung. As a portal for noninvasive delivery, pulmonary administration possesses several attractive features including a large surface area for drug absorption. Nevertheless, achieving substantial bioavailability of proteins and macromolecules by this route has remained a challenge, chiefly due to poor absorption across the epithelium. The lungs are relatively impermeable to most drugs when formulated without an absorption enhancer/promoter. In an attempt to circumvent this problem, many novel absorption promoters have been tested for enhancing the systemic availability of drugs from the lungs. Various protease inhibitors, surfactants, lipids, polymers and agents from other classes have been tested for their efficacy in improving the systemic availability of protein and macromolecular drugs after pulmonary administration. The purpose of this article is to provide the reader with a summary of recent advances made in the field of pulmonary protein delivery utilizing absorption enhancers. This report reviews the various agents used to increase the bioavailability of these drugs from the lungs, their mechanisms of action and effectiveness, and their potential for toxicity. 相似文献
996.
Faleh Tamimi Jesus Torres Khadijeh Al-Abedalla Enrique Lopez-Cabarcos Mohammad H. Alkhraisat David C. Bassett Uwe Gbureck Jake E. Barralet 《Biomaterials》2014
Onlay grafts made of monolithic microporous monetite bioresorbable bioceramics have the capacity to conduct bone augmentation. However, there is heterogeneity in the graft behaviour in vivo that seems to correlate with the host anatomy. In this study, we sought to investigate the metabolic activity of the regenerated bone in monolithic monetite onlays by using positron emission tomography–computed tomography (PET-CT) in rats. This information was used to optimize the design of monetite onlays with different macroporous architecture that were then fabricated using a 3D-printing technique. In vivo, bone augmentation was attempted with these customized onlays in rabbits. PET-CT findings demonstrated that bone metabolism in the calvarial bone showed higher activity in the inferior and lateral areas of the onlays. Histological observations revealed higher bone volume (up to 47%), less heterogeneity and more implant osseointegration (up to 38%) in the augmented bone with the customized monetite onlays. Our results demonstrated for the first time that it is possible to achieve osseointegration of dental implants in bone augmented with 3D-printed synthetic onlays. It was also observed that designing the macropore geometry according to the bone metabolic activity was a key parameter in increasing the volume of bone augmented within monetite onlays. 相似文献
997.
The study evaluated the adulterants in a specimen of illicit street heroin supplied under strict control by the Pakistan Anti‐Narcotic Force. It also examined the effects of Hypericum perforatum L. extracts on the naloxone‐induced heroin withdrawal syndrome. The GC‐MS analysis of the specimen showed that in addition to heroin (37.8%), the sample also contained caffeine (8.4%), phenobarbitone (12.7%), 6‐acetyl codeine (5.3%), 6‐acetyl morphine (10.9%) and noscapine (15.8%). Administration of the heroin to rats for 8 days induced physical withdrawal signs of abdominal constriction, diarrhoea and vocalization on touch after naloxone treatment. Aqueous Hypericum perforatum extracts (20 mg/kg twice daily chronically or as a single acute dose 90 min before naloxone) given orally to the heroin dependent rats attenuated abdominal constrictions both acutely and chronically while the hydroethanol and ethanol extracts were only effective in acutely treated animals. Diarrhoea was ameliorated by the hydroethanol and ethanol extracts following acute or chronic heroin treatment while the aqueous extract failed to show any effect. Vocalization on touch during withdrawal was reduced by all the extracts either chronically or acutely with the exception of chronic treatment with hydroethanol extracts. The findings suggest that Hypericum perforatum is capable of reducing the physical signs of opiate withdrawal. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
998.
Mild cognitive impairment(MCI)is a precursor to Alzheimer’s disease.It is imperative to develop a proper treatment for this neurological disease in the aging society.This observational study investigated the effects of acupuncture therapy on MCI patients.Eleven healthy individuals and eleven MCI patients were recruited for this study.Oxy-and deoxy-hemoglobin signals in the prefrontal cortex during working-memory tasks were monitored using functional near-infrared spectroscopy.Before acupuncture treatment,working-memory experiments were conducted for healthy control(HC)and MCI groups(MCI-0),followed by 24 sessions of acupuncture for the MCI group.The acupuncture sessions were initially carried out for 6 weeks(two sessions per week),after which experiments were performed again on the MCI group(MCI-1).This was followed by another set of acupuncture sessions that also lasted for 6 weeks,after which the experiments were repeated on the MCI group(MCI-2).Statistical analyses of the signals and classifications based on activation maps as well as temporal features were performed.The highest classification accuracies obtained using binary connectivity maps were 85.7%HC vs.MCI-0,69.5%HC vs.MCI-1,and 61.69%HC vs.MCI-2.The classification accuracies using the temporal features mean from 5 seconds to 28 seconds and maximum(i.e,max(5:28 seconds))values were 60.6%HC vs.MCI-0,56.9%HC vs.MCI-1,and 56.4%HC vs.MCI-2.The results reveal that there was a change in the temporal characteristics of the hemodynamic response of MCI patients due to acupuncture.This was reflected by a reduction in the classification accuracy after the therapy,indicating that the patients’brain responses improved and became comparable to those of healthy subjects.A similar trend was reflected in the classification using the image feature.These results indicate that acupuncture can be used for the treatment of MCI patients. 相似文献
999.
Khondakar Mohammad Salah Uddin Mohammadreza Izadifar Neven Ukrainczyk Eduardus Koenders Bernhard Middendorf 《Materials》2022,15(4)
The current contribution proposes a multi-scale bridging modeling approach for the dissolution of crystals to connect the atomistic scale to the (sub-) micro-scale. This is demonstrated in the example of dissolution of portlandite, as a relatively simple benchmarking example for cementitious materials. Moreover, dissolution kinetics is also important for other industrial processes, e.g., acid gas absorption and pH control. In this work, the biased molecular dynamics (metadynamics) coupled with reactive force field is employed to calculate the reaction path as a free energy surface of calcium dissolution at 298 K in water from the different crystal facets of portlandite. It is also explained why the reactivity of the (010), (100), and (10) crystal facet is higher compared to the (001) facet. In addition, the influence of neighboring Ca crystal sites arrangements on the atomistic dissolution rates is explained as necessary scenarios for the upscaling. The calculated rate constants of all atomistic reaction scenarios provided an input catalog ready to be used in an upscaling kinetic Monte Carlo (KMC) approach. 相似文献
1000.
Brucellosis in Saudi Arabia 总被引:1,自引:0,他引:1
This paper describes the history of brucellosis and the current public health picture in the Kingdom of Saudi Arabia. Health protection is made more difficult by several factors: (a) the local custom of drinking raw and warm milk of sheep, goats, and camels, (b) the animal reservoir of infection in the country complicated by importation of live animals both for sacrifice during Haj periods and to increase commercial flocks, and (c) by uncontrolled movements of humans and stock across political borders. 相似文献