Исследование влияния частоты и длительности импульсов на свойства покрытий, осаждаемых на титановые сплавы методом микродугового оксидирования

Объектом исследования являлись кальций-фосфатные покрытия, сформированные методом микродугового оксидирования, при различных специально подобранных режимах работы. Целью данной работы являлось исследование влияния частоты следования и длительности импульсов на физико-химические и механические свойства покрытий, сформированных методом микродугового оксидирования. В результате исследования были выявлены утверждения, которые могут быть полезны при подборе режимов для формирования специальных покрытий для разного рода применений.The object of the study is calcium-phosphate cotaing formed by microarc oxidation method on different parameters. The aim of the work is to study the effect of the repetition frequency and pulse duration on the physical, chemical and mechanical properties of coatings formed by microarc oxidation. As a result of the research, statements were identified that can be useful in selecting modes for forming special coatings for various types of applications

Circulating Nonphosphorylated Carboxylated Matrix Gla Protein Predicts Survival in ESRD

The mechanisms for vascular calcification and its associated cardiovascular mortality in patients with ESRD are not completely understood. Dialysis patients exhibit profound vitamin K deficiency, which may impair carboxylation of the calcification inhibitor matrix gla protein (MGP). Here, we tested whether distinct circulating inactive vitamin K–dependent proteins associate with all-cause or cardiovascular mortality. We observed higher levels of both desphospho-uncarboxylated MGP (dp-ucMGP) and desphospho-carboxylated MGP (dp-cMGP) among 188 hemodialysis patients compared with 98 age-matched subjects with normal renal function. Levels of dp-ucMGP correlated with those of protein induced by vitamin K absence II (PIVKA-II; r = 0.62, P < 0.0001). We found increased PIVKA-II levels in 121 (64%) dialysis patients, indicating pronounced vitamin K deficiency. Kaplan-Meier analysis showed that patients with low levels of dp-cMGP had an increased risk for all-cause and cardiovascular mortality. Multivariable Cox regression confirmed that low levels of dp-cMGP increase mortality risk (all-cause: HR, 2.2; 95% CI, 1.1 to 4.3; cardiovascular: HR, 2.7; 95% CI, 1.2 to 6.2). Furthermore, patients with higher vascular calcification scores showed lower levels of dp-cMGP. In 17 hemodialysis patients, daily supplementation with vitamin K2 for 6 weeks reduced dp-ucMGP levels by 27% (P = 0.003) but did not affect dp-cMGP levels. In conclusion, the majority of dialysis patients exhibit pronounced vitamin K deficiency. Lower levels of circulating dp-cMGP may serve as a predictor of mortality in dialysis patients. Whether vitamin K supplementation improves outcomes requires further study

Shepherds in the field abiding

Christmas hymn

За кадры. 1994. № 2

Маленькое интервью на большую тему / [беседа с] А. В. Водопьянов ; [беседовал] Н. АлександровНовое издательство университета / Б. КолесовТехнология Audio Vision / П. ХристолюбовНа ученом совете ТПУСоздан фонд 50-летия Побед

The circulating inactive form of matrix Gla Protein (ucMGP) as a biomarker for cardiovascular calcification

OBJECTIVE: Matrix gamma-carboxyglutamate (Gla) protein (MGP) is a vitamin K-dependent protein and a strong inhibitor of vascular calcification. Vitamin K deficiency leads to inactive uncarboxylated MGP (ucMGP), which accumulates at sites of arterial calcification. We hypothesized that as a result of ucMGP deposition around arterial calcification, the circulating fraction of ucMGP is decreased. Here we report on the development of an ucMGP assay and the potential diagnostic utility of monitoring serum ucMGP levels. METHODS AND RESULTS: An ELISA-based assay was developed with which circulating ucMGP can be determined. Serum ucMGP levels were measured in healthy subjects (n = 165) and in four patient populations; patients who underwent angioplasty (n = 30), patients with aortic stenosis (n = 25), hemodialysis patients (n = 52), and calciphylaxis patients (n = 10). All four patient populations had significantly lower ucMGP levels. In angioplasty patients and in those with aortic stenosis, some overlap was observed with the control population. However, in the hemodialysis and calciphylaxis populations, virtually all subjects had ucMGP levels below the normal adult range. CONCLUSION: Serum ucMGP may be used as a biomarker to identify those at risk for developing vascular calcification. This assay may become an important tool in the diagnosis of cardiovascular calcification