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991.
Immobilized Pd nanoparticles on a new ligand, namely, tris(pentaethylene-pentamine)triazine supported on graphene oxide (Pdnp-TPEPTA(L)-GO) was introduced as a novel and robust heterogeneous catalyst for use in C–C bond formation reaction. The Pdnp-TPEPTA(L)-GO catalyst was synthesized by complexation of Pd with TPEPTA as a ligand with high N-ligation sites that were supported on graphene oxide through 3-chloropropyltrimethoxysilane. The prepared catalyst was characterized using some microscopic and spectroscopic techniques. The TPEPTA(L)-GO substrate is a 2D heterogeneous catalyst with a high specific surface area and a large amount of N-ligation sites. The Pdnp-TPEPTA(L)-GO catalyst used in the C–C bond formation reaction between aryl or heteroaryl and phenylboronic acid derivatives was applied towards the synthesis of biaryl units in high isolated yields. Notably, a series of competing experiments were performed to establish the selectivity trends of the presented method. Also, this catalyst system was reusable at least six times without a significant decrease in its catalytic activity.Immobilized Pd nanoparticles on a new ligand, namely, tris(pentaethylene-pentamine)triazine supported on graphene oxide (Pdnp-TPEPTA(L)-GO) was introduced as a novel and robust heterogeneous catalyst for use in C–C bond formation reaction. 相似文献
992.
Aim: We aimed to determine the relative frequency of febrile convulsion in children with major thalassemia to theorize that higher serum iron levels could reduce the incidence of febrile convulsion. Background: Febrile convulsion is the most common type of seizure in childhood that its causes are not fully understood. However, some risk factors have been cited such as the serum iron level. Materials and methods: Three hundred and fifty-nine children aged more than 5 years with major thalassemia who were receiving blood were enrolled as the case group. The control group consisted of 357 children without thalassemia aged 4–7 years (151 boys, 206 girls) who were referred to healthcare centers for routine health monitoring. Included data were the history of febrile convulsion, age of onset and type and the frequency of convulsions. Results: Children in control group significantly experienced more febrile convulsions than thalassemic children [4/359 (1.1%) in the thalassemic children and 14/357 (3.9%) in the control group had experienced febrile convulsions (P = 0.017)]. Conclusion: The frequency of febrile convulsion in children with major thalassemia is less than that of normal children. Children with thalassemia major may have higher serum levels of iron and such high serum iron levels might have a protective role in the children who have a vulnerability for febrile convulsions. 相似文献
993.
Karen M. Eny Helen L. Lutgers John Maynard Barbara E. K. Klein Kristine E. Lee Gil Atzmon Vincent M. Monnier Jana V. van Vliet-Ostaptchouk Reindert Graaff Pim van der Harst Harold Snieder Melanie M. van der Klauw David R. Sell S. Mohsen Hosseini Patricia A. Cleary Barbara H. Braffett Trevor J. Orchard Timothy J. Lyons Kerri Howard Ronald Klein Jill P. Crandall Nir Barzilai Sofiya Milman Danny Ben-Avraham Bruce H. R. Wolffenbuttel Andrew D. Paterson 《Diabetologia》2014,57(8):1623-1634
Aims/hypothesis
Skin fluorescence (SF) is a non-invasive marker of AGEs and is associated with the long-term complications of diabetes. SF increases with age and is also greater among individuals with diabetes. A familial correlation of SF suggests that genetics may play a role. We therefore performed parallel genome-wide association studies of SF in two cohorts.Methods
Cohort 1 included 1,082 participants, 35–67 years of age with type 1 diabetes. Cohort 2 included 8,721 participants without diabetes, aged 18–90 years.Results
rs1495741 was significantly associated with SF in Cohort 1 (p?<?6?×?10?10), which is known to tag the NAT2 acetylator phenotype. The fast acetylator genotype was associated with lower SF, explaining up to 15% of the variance. In Cohort 2, the top signal associated with SF (p?=?8.3?×?10?42) was rs4921914, also in NAT2, 440 bases upstream of rs1495741 (linkage disequilibrium r 2?=?1.0 for rs4921914 with rs1495741). We replicated these results in two additional cohorts, one with and one without type 1 diabetes. Finally, to understand which compounds are contributing to the NAT2–SF signal, we examined 11 compounds assayed from skin biopsies (n?=?198): the fast acetylator genotype was associated with lower levels of the AGEs hydroimidazolones of glyoxal (p?=?0.017).Conclusions/interpretation
We identified a robust association between NAT2 and SF in people with and without diabetes. Our findings provide proof of principle that genetic variation contributes to interindividual SF and that NAT2 acetylation status plays a major role. 相似文献994.
Mahdieh Ghofrani Leila Rezaie Shirmard Pouya Dehghankelishadi Mohsen Amini Farid A. Dorkoosh 《Journal of pharmaceutical sciences》2019,108(9):3036-3045
Octreotide (OCT) is a therapeutic peptide which is administered for the treatment of acromegaly. The purpose of this study was to design a new polyethylene glycol (PEG)–conjugated nanoparticle (PEG-NP) to overcome the short half-life and poor stability of OCT. The developed PEG-NPs were compared with non-PEGylated NPs with respect to their size, morphological characteristics, loading efficiency, release profile, and macrophage uptake. The OCT-loaded NPs and PEG-NPs were prepared by ionic complexion of chitosan (Cs) with either heparin (Hp) or PEGylated heparin (PEG-Hp). The chemical structure of PEG-Hp was confirmed by IR and proton nuclear magnetic resonance. Morphological analyses by scanning electron microscopy showed that NPs and PEG-NPs have a uniform shape. Dynamic laser scattering measurements indicated that hydrodynamic diameter of NPs and PEG-NPs were 222.5 ± 10.0 nm and 334.9 ± 6.7 nm, respectively. NPs and PEG-NPs had a positive zeta potential of about 32.5 ± 1.1 mv and 20.6 ± 2.4 mv, respectively. Entrapment efficiency was 61.4 ± 1.0% and 55.7 ± 2.4% for NPs and PEG-NPs, respectively. Compared with the NPs, the PEG-NPs exhibited a slower release profile. Subsequently, fluorescein isothiocyanate–labeled chitosanCs was synthesized and used to evaluate the stealth characteristic of PEG-NPs. In vitro macrophage uptake of fluorescently labeled NPs was measured by flow cytometry. 相似文献
995.
996.
Parisa Norouzi Mohsen Amini Fatemeh Mottaghitalab Farnaz Sadat Mirzazadeh Tekie Rassoul Dinarvand Zahra Hadavand Mirzaie Fatemeh Atyabi 《Chemical biology & drug design》2020,96(2):745-757
Dual‐targeted drug delivery system has established their reputation as potent vehicles for cancer chemotherapies. Herein, gemcitabine (Gem) was conjugated to human serum albumin (HSA) via dithiodipropionic anhydride to fabricate Gem‐HSA nanoparticles. It was hypothesized that this system can enhance the low stability of Gem and can improve its intracellular delivery. Furthermore, folate was applied as targeting agent on HSA nanoparticles for increasing the tumor selectivity of Gem. To evaluate the structural properties of synthesized products, 1H NMR and FT‐IR were performed. Moreover, HPLC was implemented for confirming the conjugation between HSA and Gem. Nanoparticles have shown spherical shape with negative charge. The release rate of Gem was dependent to the concentration of glutathione and pH. Folate‐targeted HSA nanoparticles have shown higher cytotoxicity, cellular uptake, and apoptosis induction on folate receptor overexpressing MDA‐MB‐231 cells in comparison to non‐targeted nanoparticles. Finally, it is considered that the developed dual‐targeted nanoparticles would be potent in improving the stability and efficacy of intracellular delivery of Gem and its selective delivery to cancer cells. 相似文献
997.
998.
Dehghani SM Haghighat M Imanieh MH Borzooei M Rasekhi AR 《The Turkish journal of gastroenterology》2012,23(1):72-74
Hepatic artery aneurysm in children is a very unusual pathologic entity. As most patients with this anomaly are asymptomatic, the diagnosis is usually made as an incidental finding on imaging studies performed for other reasons. Here, we report a 35-day-old infant with hepatic artery aneurysm, which was diagnosed accidentally as a liver mass during echocardiography. Considering the age of diagnosis, she most likely had a congenital type of hepatic artery aneurysm. To the best of our knowledge, this is the youngest case to be reported in the literature. 相似文献
999.
1000.