15 research outputs found

    Can Plasmon Change Reaction Path? : Decomposition of Unsymmetrical Iodonium Salts as an Organic Probe

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    Plasmon-assisted transformations of organic compounds represent a novel opportunity for conversion of light to chemical energy at room temperature. However, the mechanistic insights of interaction between plasmon energy and organic molecules is still under debate. Herein, we proposed a comprehensive study of the plasmon-assisted reaction mechanism using unsymmetric iodonium salts (ISs) as an organic probe. The experimental and theoretical analysis allow us to exclude the possible thermal effect or hot electron transfer. We found that plasmon interaction with unsymmetrical ISs led to the intramolecular excitation of electron followed by the regioselective cleavage of C–I bond with the formation of electron-rich radical species, which cannot be explained by the hot electron excitation or thermal effects. The high regioselectivity is explained by the direct excitation of electron to LUMO with the formation of a dissociative excited state according to quantum-chemical modeling, which provides novel opportunities for the fine control of reactivity using plasmon energy.Peer reviewe

    The structure of mineral and bone disorders in patients with сhronic kidney disease of the 5th dialysis stage, taking into account the presence or absence of a diagnosis of type 1 diabetes mellitus

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    BACKGROUND: In patients with end-stage CKD, receiving renal replacement therapy (RRT) with programmed hemodialysis (HD), the severity of complications is associated with metabolic disturbances: accumulation of uremic toxins, nephrogenic anemia, secondary hyperparathyroidism (SHPT), extraskeletal calcification, impaired clearance and rhythm of hormone secretion.AIM: To evaluate the main biochemical and hormonal parameters, and manifestations of mineral bone disease (MBD) in patients receiving RRT with HD, before and after hemodialysis, taking into account the presence or absence of diabetes mellitus.MATERIALS AND METHODS: We divided all patients receiving RRT with HD in two groups: #1 (n=24) — patients with DM, #2 (n=16) — patients without DM. All of them had their blood analyzed before and immediately after the HD. Data analysis was performed with the Statistica 13 (StatSoft, USA). A prognostically significant model was considered at p<0.05.RESULTS: The level of iPTH, both at baseline and after HD, was lower in group #1 (p<0.001). The level of alkaline phosphatase (AP) was significantly higher in group #2 (p=0.012). In both groups before HD, a high incidence of hypocalcemia was detected (according to albumin-corrected calcium in group #1 in 58.3%, in group #2 in 43.7% of cases, p = 0.366) and hyperphosphatemia (in 66.7% and in 43 .7% of cases, respectively, p=0.151). Hypocalcemia after HD in group #1 persisted in 14%, in group #2 — in 20% of cases (p>0.05); hyperphosphatemia in group #1 was completely leveled, in group #2 it persisted in 7% of cases (p=0.417). Prior to the HD session, group #1 had significantly higher levels of RAGE, glucagon, immunoreactive insulin (IRI), cortisol, and glucose than after the HD session (p<0.05). In group #2, after HD, the levels of glucagon, IRI and cortisol significantly decreased (p<0.05), and the level of 3-nitrotyrosine (3-HT) increased significantly (p=0.026). In group #1, fibrocalcinosis of the heart valves according to ECHO and calcification of the arteries of the lower extremities according to ultrasonic doplerography were more common than in group #2 (42% vs 25%, p<0.001 and 75% vs 37.5%, p=0.018, respectively). (χ2)). Compression fractures occurred with the same frequency in both groups (60%). A decrease in bone mineral density (BMD) to the level of osteopenia was noted more often in group #1 (50% vs 18.8%), and osteoporosis was more common in group #2 (68.8% vs 33.3%) (p<0.001, χ2).CONCLUSION: The low level of PTH in group #1 may reflect the effect of diabetes on calcium-phosphorus metabolism. Patients with DM have an increased risk of renal osteodystrophy with a low bone turnover because of a number of metabolic factors inherent in diabetes. At the same time, the dynamics of phosphorus and calcium indicators during the HD procedure were similar
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