73 research outputs found
Facile synthesis and characterization of Bi13S18I2 films as a stable supercapacitor electrode material
Environmental monitoring of linear alkylbenzene sulfonates and physicochemical characteristics of seawater in El-Mex Bay (Alexandria, Egypt)
Review of nanomaterials in dentistry: interactions with the oral microenvironment, clinical applications, hazards, and benefits.
Interest in the use of engineered nanomaterials (ENMs) as either nanomedicines or dental materials/devices in clinical dentistry is growing. This review aims to detail the ultrafine structure, chemical composition, and reactivity of dental tissues in the context of interactions with ENMs, including the saliva, pellicle layer, and oral biofilm; then describes the applications of ENMs in dentistry in context with beneficial clinical outcomes versus potential risks. The flow rate and quality of saliva are likely to influence the behavior of ENMs in the oral cavity, but how the protein corona formed on the ENMs will alter bioavailability, or interact with the structure and proteins of the pellicle layer, as well as microbes in the biofilm, remains unclear. The tooth enamel is a dense crystalline structure that is likely to act as a barrier to ENM penetration, but underlying dentinal tubules are not. Consequently, ENMs may be used to strengthen dentine or regenerate pulp tissue. ENMs have dental applications as antibacterials for infection control, as nanofillers to improve the mechanical and bioactive properties of restoration materials, and as novel coatings on dental implants. Dentifrices and some related personal care products are already available for oral health applications. Overall, the clinical benefits generally outweigh the hazards of using ENMs in the oral cavity, and the latter should not prevent the responsible innovation of nanotechnology in dentistry. However, the clinical safety regulations for dental materials have not been specifically updated for ENMs, and some guidance on occupational health for practitioners is also needed. Knowledge gaps for future research include the formation of protein corona in the oral cavity, ENM diffusion through clinically relevant biofilms, and mechanistic investigations on how ENMs strengthen the tooth structure
A new class of glycomimetic drugs to prevent free fatty acid-induced endothelial dysfunction
Background: Carbohydrates play a major role in cell signaling in many biological processes. We have developed a set of glycomimetic drugs that mimic the structure of carbohydrates and represent a novel source of therapeutics for endothelial dysfunction, a key initiating factor in cardiovascular complications. Purpose: Our objective was to determine the protective effects of small molecule glycomimetics against free fatty acidinduced endothelial dysfunction, focusing on nitric oxide (NO) and oxidative stress pathways. Methods: Four glycomimetics were synthesized by the stepwise transformation of 2,5dihydroxybenzoic acid to a range of 2,5substituted benzoic acid derivatives, incorporating the key sulfate groups to mimic the interactions of heparan sulfate. Endothelial function was assessed using acetylcholineinduced, endotheliumdependent relaxation in mouse thoracic aortic rings using wire myography. Human umbilical vein endothelial cell (HUVEC) behavior was evaluated in the presence or absence of the free fatty acid, palmitate, with or without glycomimetics (1µM). DAF2 and H2DCFDA assays were used to determine nitric oxide (NO) and reactive oxygen species (ROS) production, respectively. Lipid peroxidation colorimetric and antioxidant enzyme activity assays were also carried out. RTPCR and western blotting were utilized to measure Akt, eNOS, Nrf2, NQO1 and HO1 expression. Results: Ex vivo endotheliumdependent relaxation was significantly improved by the glycomimetics under palmitateinduced oxidative stress. In vitro studies showed that the glycomimetics protected HUVECs against the palmitateinduced oxidative stress and enhanced NO production. We demonstrate that the protective effects of preincubation with glycomimetics occurred via upregulation of Akt/eNOS signaling, activation of the Nrf2/ARE pathway, and suppression of ROSinduced lipid peroxidation. Conclusion: We have developed a novel set of small molecule glycomimetics that protect against free fatty acidinduced endothelial dysfunction and thus, represent a new category of therapeutic drugs to target endothelial damage, the first line of defense against cardiovascular disease
Assessment of provocative inflammatory role of tristetraprolin and tumor necrosis factor alpha genes expression in chronic kidney disease
Renal inflammation is a prominent feature of chronic kidney disease (CKD). The determinants of renal function decay are not completely comprehended. Tristetraprolin (TTP) and tumor necrosis factor (TNF-α) are immune mediators and affect renal inflammation. This study was planned to estimate gene expression of both TTP and TNF-α in CKD. One hundred fifty subjects were rolled in this study (55 CKD patients with hypertension, 45 CKD patients without hypertension and 50 healthy subjects). Renal functions, lipid profile & blood glucose were estimated from serum. TTP and TNF-α genes expression were assessed from whole blood samples by real time PCR. The results showed that TTP expression was significantly down-regulated while TNF-α was up-regulated in CKD patients with and without hypertension compared with healthy controls. It could be concluded that TTP and TNF-α may have a provocative inflammatory role in renal illness and may be utilized as promising biomarkers and therapeutic focus in CKD.Keywords: Chronic kidney disease; Inflammation; Tristetraprolin, Tumor necrosis facto
Ultrasound-assisted green synthesis of silver nanoparticles and their incorporation in antibacterial cellulose packaging
Photocatalytic study of some synthesized MWCNTs/TiO2 nanocomposites used in the treatment of industrial hazard materials
Acute and chronic changes in the control of breathing in a rat model of bronchopulmonary dysplasia
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