Drought-induced molecular changes in crown of various barley phytohormone mutants.

One of the main signal transduction pathways that modulate plant growth and stress responses, including drought, is the action of phytohormones. Recent advances in omics approaches have facilitated the exploration of plant genomes. However, the molecular mechanisms underlying the response in the crown of barley, which plays an essential role in plant performance under stress conditions and regeneration after stress treatment, remain largely unclear. The objective of the present study was the elucidation of drought-induced molecular reactions in the crowns of different barley phytohormone mutants. We verified the hypothesis that defects of gibberellins, brassinosteroids, and strigolactones action affect the transcriptomic, proteomic, and hormonal response of barley crown to the transitory drought influencing plant development under stress. Moreover, we assumed that due to the strong connection between strigolactones and branching the hvdwarf14.d mutant, with dysfunctional receptor of strigolactones, manifests the most abundant alternations in crowns and phenotype under drought. Finally, we expected to identify components underlying the core response to drought which are independent of the genetic background. Large-scale analyses were conducted using gibberellins-biosynthesis, brassinosteroids-signaling, and strigolactones-signaling mutants, as well as reference genotypes. Detailed phenotypic evaluation was also conducted. The obtained results clearly demonstrated that hormonal disorders caused by mutations in the HvGA20ox2, HvBRI1, and HvD14 genes affected the multifaceted reaction of crowns to drought, although the expression of these genes was not induced by stress. The study further detected not only genes and proteins that were involved in the drought response and reacted specifically in mutants compared to the reaction of reference genotypes and vice versa, but also the candidates that may underlie the genotype-universal stress response. Furthermore, candidate genes involved in phytohormonal interactions during the drought response were identified. We also found that the interplay between hormones, especially gibberellins and auxins, as well as strigolactones and cytokinins may be associated with the regulation of branching in crowns exposed to drought. Overall, the present study provides novel insights into the molecular drought-induced responses that occur in barley crowns.

[Influence of elevated homocystein level and selected lipid parameters in kidney transplant patients on the progression of atherosclerotic changes assessed by intima-media thickness index (CCA-IMT)]. / Ocena wplywu hiperhomocysteinemii i wybranych parametrów lipidowych u chorych po przeszczepieniu nerki na rozwój zmian miazdzycowych ocenianych wskaznikiem intima-media (CCA-IMT).

UNLABELLED: The aim of the study was to evaluate the influence of elevated homocystein (Hcy) level and selected lipid parameters on the progression of atherosclerotic changes in patients after kidney transplantation (KTx). PATIENTS AND METHODS: The study included 51 pts (17 F, 34 M) aged 15-62 years (median 38.1) after cadaver KTx. The mean observation period equaled 21.2 months (6-24 months); while total observation period was 90 patients/ years. Hcy levels was measured using HPLC, Lp(a) and Apo-B levels using the nephelometric method and total cholesterol with its' HDL and LDL fractions, triglycerides and creatinine based on the Hitachi 917 analyzer. Patients' blood was drawn before renal transplantation and 3, 6, 9, 12, 15, 18, 21 and 24 months after KTx. Common carotid artery intima media thickness (CCA-IMT) was evaluated by ultrasound on 14 days, 12 and 24 months after KTx. RESULTS: CCA-IMT correlated significantly with Hcy levels after 12 months (R=0.53; p=0.0009) and 24 months (R=0.38; p=0.0356) after KTx. Significant differences were found 12 and 24 months after KTx in CCA-IMT between patients with normal (<15 micromol/l) and increased (>15 micromol/ l) mean Hcy concentrations: p=0.0035 and p= 0.015, respectively. Analyzing changes in CCA-IMT, significant differences were noted when comparing the CCA-IMT increment after 12 and 24 months post KTx in patients with normal (< or =15 micromol/l) and increased (>15 micromol/l) homocystein concentrations: p=0.049 and p=0.0039, respectively. Increment of CCA-IMT 12 months after KTx, significantly correlated with mean total cholesterol level (R=0.35; p=0.0333), whereas 24 months after procedure correlated significantly with 0.0315). CONCLUSIONS: Hcy level is an independent risk factor for atherosclerosis development in patients after KTx. Elevated Hcy level as well as increased cholesterol and Lp(a) levels enhance the progression of atherosclerotic changes evaluated by CCA-IMT in KTx patients.

[Cardiovascular calcification and five-years mortality in patients on maintenance hemodialysis]. / Zwapnienia w ukladzie sercowo-naczyniowym a 5-letnia smiertelnosc pacjentów leczonych powtarzanymi hemodializami.

The very high cardiovascular mortality and morbidity in hemodialyzed patients (HD) is strongly associated with cardiovascular calcification. The aim of the study was to find the predictors of mortality in HD patients during 5-years observation period. The study group was composed of 64 patients (35 F, 29 M) aged 25-75 years (mean 48.9) hemodialyzed three times a week for 12-275 months (mean 77.8). The levels of hemoglobin, total protein, albumin, Ca, P, Ca x P, iPTH, cholesterol, triglycerides, fibrinogen, insulin, homocysteine, leptin, procalcitonin, CRP, IL-6, TGF-beta, PDGF were assessed and all patients underwent Calcium Score (CS) of coronary arteries (CACS) calculation using MSCT and B-mode ultrasound of carotid arteries for intima-media thickness (CCA-IMT), as well as echocardiographic assessment with LVMI calculation and heart valves evaluation at the start of observation. The self-elaborated Cumulative Calcification Index (CCl) was calculated as a sum of CACS Index according to Rumberger et al. (CS<10-0, 10400 - 3 points); number of calcified plaques in carotid arteries (0-0, 1 - 1, 2 - 2, 3 and more - 3 points) and the number of calcified heart valves. At the start of the study the median value of CCl was 4 and interquartile range 4. Only 2 (3%) patients were free of any type of cardiovascular calcification (CCl =0), 15 (23%) patients had minimal calcification (CCl 1 to 2 points), 33 (52%) average (2 - 6 points) and 14 (22%) patients had severe calcification (CCl>6). 21 (32,8%) patients died during observation period. Patients who died were older (56.9 vs. 45.3 yrs.) and had higher CS at the start (1275 vs. 356), higher CCA-IMT (0.948 vs. 0.687 mm) and CCl (6.15 vs. 3.63) values. Those patients had also higher CRP (0.645 vs. 0.245 mg/dl) and IL-6 (10.16 vs. 4.15 pg/ml) levels (p<0.05). LVMI and mean: hemoglobin, total protein, albumin, Ca, P, Ca x P, iPTH, cholesterol, triglycerides, fibrinogen, insulin, homocysteine, leptin, procalcitonin, TGF-beta as well as PDGF levels did not differ between the groups. In logistic regression model (p<0.00002), among tested parameters only CCl was an independent and statistically significant factor of mortality with OR=1.82 per every point of CCl (p<0.0003). Cardiovascular calcification expressed as CCl confirmed to be a strong predictor of mortality in HD patients.

[Influence of microinflammation and oxidative stress on atherosclerosis progression and calcifications in cardiovascular system of hemodialyzed patients during two years follow-up]. / Wplyw mikrozapalenia i stresu oksydacyjnego na progresje miazdzycy i zwapnien w ukladzie krazenia u chorych hemodializowanych w okresie dwuletniej obserwacji.

Atherosclerosis and calcifications in the cardio-vascular system are the most frequent causes of increased morbidity and mortality in patients with end-stage renal disease treated with hemodialyses. The aim of this study was to estimate the atherosclerosis progression and presence of calcifications in the circulatory system in patients treated with hemodialyses using, non-invasive imaging diagnostic techniques and to search for the relationships between these changes and microinflammation and oxidative stress during two years. The study was performed in 73 patients (36 female and 37 male), aged 25 to 75 years (mean -49.5), treated with hemodialyses, 3 times/week for 12 to 275 months (mean -73.8). In each patient before starting hemodialysis levels of: ox-LDL, Lp (a), procalcitonin, IL-1beta, IL-6, CRP, TGFbeta, TNFalpha, PDGF, AOPP and MPO were determined. Presence of artery calcifications was detected by Multi-Row Spiral Computed Tomography (MSCT) and expressed as coronary artery calcification score (CACS). Ultrasonography was used to evaluate CCA-IMT. During the study CACS increased significantly after 12 and 24 months (p < 0.00001) as compare with baseline. After 12 months, CACS increase significantly correlated with procalcitonin level (r = 0.30 p = 0.01) and after 24 months with CRP (r = 0.46; p = 0.0002) and IL-6 (r = 0.36; p = 0.005). Independent factor of coronary artery calcification progression after 24 months of observation was only CRP (beta = 0.569). CCA-IMT increased during the study and this increase was statistically significant (p < 0.00001). CCA-IMT increase correlated with CACS growth after 12 (r = 0.36; p = 0.003) and 24 months (r = 0.39; p = 0.002). After 12 months significant relationship was noted with procalcitonin (r = 0.29; p = 0.022). After 24 months CCA-IMT correlated with AOPP (r = -0.30; p = 0.017). The independent factor of CCA-IMT progression after 24 months of observation was only CACS (delta CACS beta = 0.49). From the performed study, we can conclude that exacerbation of atherosclerosis and calcification in the circulatory system of patients treated with maintenance hemodialyses depends on microinflammation and oxidative stress. Reasonable tools for diagnostic algorithm estimation of atherosclerosis advancement in this group of patients are non-invasive, visual diagnostic techniques such as MSCT and ultrasonography.

Factors involved in vascular calcification and atherosclerosis in maintenance haemodialysis patients.

BACKGROUND: Atherosclerosis and vascular calcifications are common causes of morbidity and mortality in maintenance haemodialysis patients. In addition to the well-known traditional risk factors, uraemia-specific factors appear to enhance dramatically the progression of the pathological processes involved. The aim of the present study was to evaluate the degree of atherosclerosis and vascular calcifications in chronic haemodialysis patients using non-invasive imaging methods, and to identify potentially involved factors. METHODS: The study included 73 patients (36 females, 37 males), aged 25-75 years, who were on haemodialysis treatment for 12-275 months (mean dialysis vintage 73.8 months). We assessed the following circulating parameters: calcium (Ca), phosphorus, 'intact' parathyroid hormone (iPTH), 25OH vitamin D, lipids, oxidized LDL (ox-LDL), Lp(a), homocysteine, leptin, IL-1-beta, IL-6, CRP, TGF-beta, TNF-alpha, (PDGF), advanced oxidation protein products (AOPP) and myeloperoxidase activity (MPO). Coronary artery calcification score (CACS) was assessed using multi-row spiral CT (MSCT). Intima-media thickness index of the common carotid artery (CCA-IMT) and presence of cervical artery atherosclerotic plaques were evaluated by ultrasonography. RESULTS: Coronary artery calcifications were observed in 79.5% of the patients, with CACS ranging from 0 to 4987. In univariate analysis, a positive correlation was observed between CACS and age, BMI, iPTH, CRP, IL-6 and CCA-IMT, whereas an inverse correlation existed with 25OH vitamin D, TGF-beta and PDGF. CCA-IMT ranged from 0.4 to 1.1 mm. It was positively correlated, in univariate analysis, with age, CACS, CRP and Il-6, and negatively with 25OH vitamin D, TGF-beta and PDGF. Only CACS remained as independent predictive factor of CCA-IMT in multivariate analysis. Atherosclerotic plaques were found in the carotid arteries of 53 patients (72%). The number of plaques was positively correlated with age, CACS, phosphorus, MPO, CRP and IL-6, and inversely with 25OH vitamin D in univariate analysis. In multivariate regression analysis, only age and CACS remained as independent variables. CONCLUSION: In addition to classic risk factors, the degree of atherosclerosis and vascular calcification in our dialysis patient population were associated with several factors that are frequently abnormal in advanced chronic renal failure, but except age, all of them were interdependent. Notably, as in the general population, CACS was an independent predictor of the degree of atherosclerosis in haemodialysis patients.

[Present opinions concerning the administration of low molecular weight heparins in hemodialysis patients]. / Wspólczesne poglady na temat zastosowania heparyn drobnoczasteczkowych u chorych hemodializowanych.

Intradialytic anticoagulation is an essential element of the dialysis procedure. Patients with end stage renal failure, due to the repetitive nature of dialysis sessions are exposed in a chronic manner to side effects of drugs applied during the procedure. Popular administration of unfractionated heparin, concerning its unstable pharmacokinetic profile may cause thrombocytopenia, enhance hyperkalemia, osteoporosis, and lipid disturbances. In the past years, a clinical alternative to unfractionated heparin have become, as well as in dialysis therapy, low molecular weight heparins. Beside the beneficial pharmacokinetic aspect, these heparins are characterized by decreasing number and less intensified side effects associated with their administration.

Changes in common carotid artery intima-media thickness over 1 year in patients on peritoneal dialysis.

BACKGROUND: Accelerated atherosclerosis and vascular calcifications increase cardiovascular morbidity and mortality in patients on dialysis. Common carotid artery (CCA) intima-media thickness (IMT) is considered useful for imaging atherosclerosis non-invasively. Since chronic inflammation may accelerate atherosclerosis in end-stage renal disease patients, the aim of this 1 year study was to assess changes in CCA-IMT in stable peritoneal dialysis (PD) patients, and to search for possible associations between these changes and selected cytokines, acute phase proteins and other risk factors of atherosclerosis. METHODS: Of the original cohort of 61 stable patients on PD-28 female, 33 male; mean age 50.4+/-13.6 years; dialyse for a median of 17.5 months at inclusion (range 1-96 months)-47 patients survived the 1 year period on PD. CCA-IMT was assessed at baseline and after 12 months. Pro-inflammatory cytokines (IL-6, TNFalpha), acute phase proteins (CRP, fibrinogen), calcium-phosphate balance and lipid profile were assessed at baseline and after 6 and 12 months. Anthropometric parameters (age, weight, BMI, waist-to-hip ratio) were measured at baseline. RESULTS: The mean CCA-IMT at baseline, 0.66+/- 0.19 mm, increased by a mean of 0.098+/-0.17 to 0.76+/-0.21 mm (P<0.001) in 1 year. In 14 patients (29.8%) at least one plaque was found in the CCAs examined. At the end of follow-up: 28 patients (59.6%) had increases in CCA-IMT (from 0.63+/-0.2 to 0.83+/- 0.21 mm; P = 0.03), and 19 (40.4%) remained stable or even showed slight, but non-significant, decreases of CCA-IMT (from 0.72+/-0.17 to 0.66+/-0.17 mm, P = NS). The 'progressors' had significantly higher initial BMI (P<0.05), and mean concentrations of calcium (P = 0.005), IL-6 (P = 0.05), TNFalpha (P = 0.05), CRP (P = 0.005) and lower HDL-cholesterol than 'non-progressors'. In univariate analysis, DeltaCCA-IMT correlated positively with age (R = 0.32, P = 0.03), BMI (R = 0.29, P = 0.05) and mean concentrations of CRP (R = 0.37, P = 0.01), TNFalpha (0.52, P = 0.0002), but inversely with HDL-cholesterol (R = -0.37, P = 0.01). In multiple regression analysis, however, only age appeared to be independently associated with increase in CCA-IMT (beta = 0.37, P<0.01; R(2) for the model 0.14). CONCLUSIONS: Our results suggest a possible role of non-specific inflammation in the progression of atherosclerosis in patients treated with PD, in addition to age.

[Hyperhomocysteinemia and advancement of atherosclerosis in patients with chronic renal failure on maintenance hemodialysis]. / Hiperhomocysteinemia a zaawansowanie miazdzycy tetnic u chorych z przewlekla niewydolnoscia nerek leczonych hemodializami.

Cardiovascular diseases connected with atherosclerosis are the main factor of morbidity and mortality in patients with end-stage renal failure. Hyperhomocysteinemia is a known and independent risk factor of atherosclerosis, occurring in 85-95% patients treated with hemodialysis. The aim of this study was to analyse relation between plasma level of homocysteine and chosen indicators of atherosclerosis development and also examined retrospectively cardiovascular complications in these patients. The study was carried out in 100 patients on hemodialysis who were divided into two groups: 72 patients with mild (20.74 mumol/l +/- 3.75) and 28 patients with moderate hyperhomocysteinemia (38.81 mumol/l +/- 9.81). Ultrasonographic examinations of Carotid Communis Artery Intima-Media Thickness (IMT), Ankle-Arm Blood Pressure Index (AABPI), echocardiographic parameters and biochemical examinations such as: PTH, folic acid and Vitamin B12, total protein, albumin, fibrinogen, glucose, total, LDL and HDL cholesterol, transferring, apolipoprotein B, lipoprotein (a), sodium potassium, calcium, phosphate, magnesium, iron, ferritin, urea, creatinine, uric acid and value of Hb, Ht, total iron binding capacity and transferring saturation, were performed. Patients with hypertension were divided into groups according to the number of taken anti-hypertensive drugs. Hyperhomocysteinemia was confirmed in 96% of patients. Frequency and type of acute cardiovascular complications were not related with the level of hyperhomocysteinemia. Statistically significant difference between IMT and level of hyperhomocysteinemia was observed. In patients with mild hyperhomocysteinemia IMT was 0.68 mm +/- 0.24 whereas in patients with moderate hyperhomocysteinemia 0.80 mm +/- 0.25, p < 0.036). Positive correlation between level of homocysteine and IMT (r = 0.22, p < 0.03) was noted. Based on this study, we concluded, that measurement of intima-media thickness is a good indicator of atherosclerosis development and correlates with hyperhomocysteinemia in patients on maintenance hemodialysis. It clearly confirms the role of hyperhomocysteinemia as significant risk factor of atherosclerosis in those patients.

[Evaluation of atherosclerosis progression in patients treated repeatedly with hemodialysis]. / Ocena stopnia rozwoju miazdzycy u chorych leczonych powtarzanymi hemodializami.

The main cause of increased morbidity and mortality in patients on maintenance hemodialysis are cardiovascular complications due to accelerated atherosclerosis. Lipid profile disturbances, increased levels of homocysteine (HC), fibrinogen, iPTH as and Ca-P abnormalities seem to be the important factors in atherosclerosis progression. The aim of the study was to evaluate the advancement of atherosclerosis in patients on maintenance hemodialysis and to assess levels of pro-atherosclerotic factors. The study included 50 patients (30 M, 20 F) aged 21-75 years (mean 48.6 y) hemodialyzed three times a week for 12 to 282 months (mean 114.5 m). The homocysteine, fibrinogen, iPTH, calcium, phosphate and indices of lipid metabolism such as total cholesterol, HDL, LDL, triglicerides, Lp (a) and Apo B were measured before hemodialysis. To evaluate the advancement of atherosclerosis, all patients underwent MSCT using Somatom plus 4 apparatus with calcium scoring (CS) calculation and B-mode ultrasound for IMT using Acuson 128 XP 10 apparatus. The above applied methods helped to evaluate changes in central and peripheral arteries. In CS testing, coronary artery calcifications were present in 36 patients (72%). The CS ranged from 0 to 4345, with the mean CS being 584 (SD = 1012). The CS correlated significantly with age (r = 0.39; p < 0.005), P (r = 0.33; p < 0.05), CaxP product (r = 0.39; p < 0.05), iPTH (r = 0.43; p < 0.001) and with IMT (r = 0.56; p < 0.0001). The IMT ranged from 0.5 to 1.5, with mean of 0.89 (SD = 0.28). The IMT correlated significantly with age (r = 0.54; p < 0.0001), time on dialysis (r = 0.40; p < 0.01), fibrinogen (r = 0.43; p < 0.02), LDL (r = 0.30; p < 0.05), P (r = 0.29; p < 0.05), and CaxP product (r = 0.3; p < 0.05). Based on our study, we conclude that age, time on dialysis, increased levels of homocysteine, LDL cholesterol, fibrinogen, P, and iPTH as well as Ca-P disturbances are strong predictors of atherosclerosis in HD patients.