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991.
992.
Zhanqi Wang Leng Ni Jing Wang Chengran Lu Meng Ren Wei Han Changwei Liu 《Journal of pineal research》2016,60(2):217-227
Smoking is one of the most harmful lifestyles in the world. Very few studies have investigated the effects of melatonin in smoke‐induced vascular injury. This study was designed to investigate whether melatonin could protect rats and humans from smoke‐induced vascular injury. 32 male rats and a double‐blind randomized controlled trial (RCT) containing 63 participants formed the subjects of this study. In rats, 10 mg/kg of melatonin was intraperitoneally injected. Blood samples and abdominal artery were harvested two weeks later. Melatonin decreased the expression of platelet endothelial cell adhesion molecule‐1 (CD31), intercellular adhesion molecule‐1 (ICAM‐1), vascular cell adhesion molecule‐1 (VCAM‐1) and endothelin‐1 (ET‐1) compared with the smoke exposed group (P < 0.05), whereas endothelial nitric oxide synthase (eNOS), nuclear erythroid 2‐related factor 2 (Nrf2), NAD(P)H quinone oxidoreductase 1 (NQO‐1), catalytic glutamate cysteine ligase (GCLC) and heme oxygenase‐1 (HO‐1) recovered markedly (P < 0.05). In humans, 3 mg/day of melatonin was taken orally by the participants. Blood samples were drawn at baseline and after two weeks of treatment. Compared with the oral placebo group, melatonin decreased the concentration of fibrinogen (Fbg) (P = 0.04) and free fatty acids (FFA) (P = 0.04) in smokers, along with the decreased expression of ICAM‐1, VCAM‐1 and ET‐1 (P = 0.004, P = 0.001, P < 0.0001, respectively). In contrast, Nrf2 and HO‐1 expression were markedly increased (P = 0.0001, P = 0.0049, respectively) after smokers took melatonin orally. In summary, our present data suggest that melatonin could ameliorate smoke‐induced vascular injury. 相似文献
993.
《Vaccine》2017,35(40):5373-5380
The influenza A virus undergoes genetic drift and shift, leaving the general population susceptible to emerging pandemic strains, despite seasonal flu vaccination. Here we describe a single dose influenza vaccine derived from recombinant outer membrane vesicles (rOMVs) that display an antigen-mapped heterospecies tandem sequence of the M2 protein from the influenza A virus, released over 30 days from poly(lactic-co-glycolide) (PLGA) microparticles. Four weeks post vaccination, BALB/c mice developed high anti-M2e IgG titers that were equivalent to those generated at 8 weeks in a typical prime/boost vaccine regimen. Challenge of mice with a lethal dose of mouse adapted influenza virus PR8 (H1N1) 10 weeks post vaccination resulted in 100% survival for both rOMV single-dose microparticle and prime/boost vaccinated mice. Anti-M2e IgG1 and IgG2a antibody titers were weighted toward IgG1, but splenocytes isolated from rOMV single-dose microparticle vaccinated mice produced high levels of IFNγ relative to IL-4 in response to stimulation with M2e peptides, supporting a more Th1 biased immune response. The protective immune response was long lasting, eliciting sustained antibody titers and 100% survival of mice challenged with a lethal dose of PR8 six months post initial vaccination. Together, these data support the potential of controlled release rOMVs as an effective single dose, long lasting and rapidly effective vaccine to protect against influenza. 相似文献
994.
995.
Lena Lindholm Anders Bengtsson Vigdis Hansdottir Anne Westerlind Anders Jeppsson 《Scandinavian cardiovascular journal : SCJ》2013,47(5):347-352
Objective - Insulin is a vasodilating agent and it was hypothesized that insulin (GIK) could improve systemic and regional oxygenation in cardiac surgery with cardiopulmonary bypass (CPB). Two questions were addressed: 1) Does insulin improve central mixed and hepatic venous oxygenation during CPB? and 2) Does this treatment reduce systemic levels of the proinflammatory mediators C3a and IL-6? Design - Prospective, randomized, controlled study at a university hospital. Thirty patients were included and 16 of these received an infusion of insulin, glucose and potassium (GIK) using an euglycemic clamp technique. The insulin infusion was started during hypothermia, 15 min before rewarming. Blood gases and hemodynamic parameters were measured during hypothermia (before the insulin infusion was started), during rewarming at 35°C, and 30 min after CPB was discontinued. Inflammatory markers were measured: preoperatively, during hypothermia and 2 h after CPB. Results - GIK was associated with reduced systemic vascular resistance ( p = 0.02 vs the control group), higher bypass pump flow ( p = 0.001), higher central mixed oxygen saturation ( p = 0.036) and oxygen tension ( p = 0.001) and higher hepatic venous oxygen saturation ( p = 0.04) and oxygen tension ( p = 0.006). C3a and IL-6 increased during surgery in both groups but there were no differences between the groups. Conclusion - 1) GIK infusion improved central mixed and hepatic venous oxygenation in patients undergoing heart surgery. 2) During the conditions of this study, this had no effect on the proinflammatory mediators C3a and IL-6. 相似文献
996.
Ian K.Y. Lo Atiba A. Nelson Stephen S Burkhart 《International journal of shoulder surgery》2013,7(4):139-142
The technique of arthroscopic subscapularis repair continues to evolve. A three-sided subscapularis release (e.g. anterior, posterior, superior) is commonly advocated for improving tendon excursion to bone. However, a lateral release is commonly required as well, particularly for full thickness, upper subscapularis tears and full thickness, complete subscapularis tears. We describe the techniques to identify and release the lateral subscapularis border, which aids in the completion of other releases. 相似文献
997.
《Journal of microencapsulation》2013,30(5):463-474
An experimental and theoretical methodology is proposed to calculate the permeability of microcapsules that contain a core of oil-based active ingredient. Theoretical analysis is performed considering the polydispersity of the measurable capsule size, which allows the estimation of the permeability polydispersity via three different methods. The models proposed were applied in order to determine the permeability of melamine-formaldehyde microcapsules with hexyl salicylate as core oil. Release experiments were performed with four different co-solvents (ethanol, propan-1-ol, propan-2-ol and 1,3-butanediol) of different concentration. Permeability values were found to be constant, despite a two order magnitude of difference in the solubility concentrations. 相似文献
998.
《Journal of microencapsulation》2013,30(7):626-635
Poly(N-isopropylacrylamide) (PNIPA) and Poly(N-isopropylacrylamide-co-acrylic acid) (P(NIPA-co-AA)) microgels loaded with 5-aminolevulinic acid (ALA) were prepared by the spray-drying method. The amount of drug loaded was 290?µg ALA/mg microgel for PNIPA and 244?µg ALA/mg microgel for P(NIPA-co-AA) microgels. Maximum in vitro drug release took place within 15–30?min for PNIPA and 1–1.5?h for P(NIPA-co-AA) microgels as a function of pH, at 37°C. Transdermal delivery from microgels showed permeation fluxes 10 times higher than the passive diffusion flux. The cytotoxicity of microgels synthesized in HeLa cells after the application of photodynamic therapy (PDT) was superior compared with the administration of ALA in solution alone. Finally, the use of these microgels as a delivery vehicle for ALA constitutes a system capable of enhancing its topical administration and PDT effectiveness. 相似文献
999.
Laura Nolting MD Patrick Hunt MD Thomas Cook MD Barton Douglas MD 《Journal of ultrasound in medicine》2016,35(4):819-822
Ultrasound models, commonly referred to as “phantoms,” are simulation tools for ultrasound education. Commercially produced phantoms are available, but there are “homemade” alternatives such as raw poultry and gelatin molds. Precooked, processed meat, better known as SPAM (Hormel Foods Corporation, Austin, MN), can be used as an ultrasound phantom to teach several ultrasound applications. It is a versatile, hygienic, and easily manipulated medium that does not require refrigeration or preparatory work and can be easily discarded at the end of use. 相似文献