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The production of reactive oxygen and nitrogen species (RONS) by skeletal muscle is important as it (i) underlies oxidative damage in many degenerative muscle pathologies and (ii) plays multiple regulatory roles by fulfilling important cellular functions. Superoxide and nitric oxide (NO) are the primary radical species produced by skeletal muscle and studies in the early 1980s demonstrated that their generation is augmented during contractile activity. Over the past 30 years considerable research has been undertaken to identify the major sites that contribute to the increased rate of RONS generation in response to contractions. It is widely accepted that NO is regulated by the nitric oxide synthases, however the sites that modulate changes in superoxide during exercise remain unclear. Despite the initial indications that the mitochondrial electron transport chain was the predominant source of superoxide during activity, with the development of analytical methods a number of alternative potential sites have been identified including the NAD(P)H oxidases, xanthine oxidase, cyclooxygenases, and lipoxygenases linked to the activity of the phospholipase A2 enzymes. In the present review we outline the subcellular sites that modulate intracellular changes in superoxide in skeletal muscle and based on the available experimental evidence in the literature we conclude that the NAD(P)H oxidases are likely to be the major superoxide generating sources in contracting skeletal muscle. [ABSTRACT FROM AUTHOR]

Background. Experimental studies have shown that increased levels of parathyroid hormone (PTH) in uremia may cause elevation of intracellular calcium, predisposing to insulin resistance and lipid metabolism abnormalities. Administration of calcium-channel blockers (CCBs) in these models protects against the development of lipid profile abnormalities. This study evaluates the combined effect of intact PTH (iPTH) levels and administration of CCB on the lipid profiles of nondiabetic hemodialysis patients. Methods. One hundred and eight non-diabetic hemodialysis patients were studied for 6 months. The population was divided into four groups, according to iPTH levels and administration of CCB: (A) iPTH<70 pg/mL, administration of CCB (n=16), (B) iPTH>300 pg/mL without administration of CCB (n=43), (C) iPTH<70 pg/mL without CCB administration (n=19), and (D) iPTH>300 pg/mL with CCB administration (n=30). Serum concentrations of total cholesterol, high-density lipoprotein (HDL), triglycerides, and albumin were measured on a monthly basis. Results. All results are shown as mean±SE. Total cholesterol values (in mg/dL) were for group (A) 186±4, for group (B) 205±3, for group (C) 200±3, and for group (D) 203±4 [ p NS between (C) and (D), p<.05 for all other comparisons]. Triglycerides values (in mg/dL) were for group (A) 171±9, for group (B) 199±6, for group (C) 190±6, and for group (D) 191±9 (p NS for all comparisons). HDL values (in mg/dL) were for group (A) 43.8±1, for group (B) 35.8±1, for group (C) 38.3±0.7, and for group (D) 37.2±0.7 mg/dL [p NS between (C) and (D), p<.001 for all other comparisons]. Low-density lipoprotein values (in mg/dL) were for group (A) 107.6±4.4, for group (B) 149.3±2.5, for group (C) 131.2±2.9, and for group (D) 126.8±4.1 [p NS between (C) and (D), p<.001 for all other comparisons]. Atherogenic index... [ABSTRACT FROM AUTHOR]

To systematically review the role of ultrasound (US) in the assessment of the joint-enthesial-nail apparatus in patients with psoriatic arthritis (PsA) or psoriasis (PSO) in terms of prevalence, diagnosis, prognosis, monitoring and treatment. A systematic literature review was conducted through medical databases (PubMed, Embase) and the grey literature up to February 2018. The main areas of application of nail US were first identified, allowing the development of research questions, which were rephrased following the PICOs methodology to develop inclusion criteria. Of the 585 studies produced by PubMed and Embase searches, 17 studies met the criteria for inclusion. Five additional studies were included: 1 from the hand search and 4 from the 2016–2017 ACR and EULAR congresses. The prevalence of nail plate changes varied from < 10 to 97%, for power Doppler signal from 20–30 to 96% and distal interphalangeal joint (DIJ) involvement from 8.9 to 100%. The performance of US nail/DIJ abnormalities in the diagnosis of PsA and PSO elementary lesions was analysed by five studies, with a wide heterogeneity. Reproducibility and reliability of US nil/DIJ were assessed by interclass correlation coefficient or Cohen's k and their values ranged from 0.6 to 0.9. The value of US nail/DIJ in the monitoring of the lesions was analysed only by a single study. The analysis revealed applications for US nail/DIJ in PsA and PSO and highlights limitations. Validation is strongly needed to demonstrate its appropriateness in the clinical practice and to define its diagnostic and prognostic role. [ABSTRACT FROM AUTHOR]

Using surface force balance measurements we have established that polystyrene chains bearing three zwitterionic groups have a higher end-group sticking energy than equivalent chains bearing a single zwitterionic group. In a good solvent, polystyrene chains end-functionalized with three zwitterionic groups form brushes of a higher surface coverage than those bearing a single zwitterion. The increase in surface coverage is slow compared with the initial formation of the brush. Measurements of the refractive index allow us to directly quantify the variation of surface coverage, permitting comparison with models for the kinetics of brush formation based on scaling theory and an analytical self-consistent field. We find qualitative support for associating the kinetic barrier with the energy required for an incoming chain to stretch as it penetrates the existing brush.© 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Summary: Denosumab and zoledronic acid are potent antiresorptives. In this study in patients pre-treated with zoledronic acid, denosumab achieved similar increases with zoledronic acid in lumbar spine BMD despite the more prominent reduction of bone turnover markers. Denosumab reversibly reduced endogenous RANKL. Introduction: We aimed to compare yearly changes in lumbar spine (LS) bone mineral density (BMD), bone turnover markers, free soluble receptor activator of nuclear factor kappaB ligand (sRANKL) and sclerostin levels between denosumab and zoledronic acid. Methods: Postmenopausal women with low bone mass previously treated with zoledronic acid for 1 year were assigned to denosumab injection ( n = 32) or zoledronic acid infusion ( n = 26). Procollagen type 1 N-terminal propeptide (P1NP), C-terminal cross-linking telopeptide of type 1 collagen (CTx), sRANKL, and sclerostin levels were measured in serum samples obtained at baseline and 3, 6, and 12 months after denosumab injection or zoledronic acid infusion. LS BMD was measured at baseline and 12 months. Results: The mean LS increase was 4.5 and 4.4 % with denosumab and zoledronic acid, respectively ( p = 0.560). Denosumab caused a larger decrease in CTx at 3 months ( p < 0.001) and P1NP at 3 ( p < 0.001), 6 ( p = 0.021), and 12 months ( p = 0.042). Denosumab significantly decreased sRANKL by 87.4 % at 3 months ( p < 0.001). Sclerostin levels were not changed with either intervention ( p = 0.162 and p = 0.214, respectively). Conclusions: In patients previously treated with zoledronic acid, denosumab reduces bone turnover more than zoledronic acid, but the increases in LS BMD are comparable. Furthermore, denosumab administration results in reversible inhibition of the metabolically significant endogenous free soluble RANKL levels. Serum sclerostin is not affected by either agent. [ABSTRACT FROM AUTHOR]

Wereport on a novel synthetic route to synthesize relatively largequantities of polystyrene (PS) star polymers with targeted arm functionalityand molar mass and their rheological properties in the molten state.The synthetic route involves grafting styrene monomers onto a modified(aliphatic, alternating) polyketone backbone with a specific numberof initiating grafting sites using controlled atom transfer radicalpolymerization (ATRP). Several polyketone precursors were used. Thisresulted in a large array of star polystyrenes with nonspherical coresand varying average arm length and number of arms. Their linear viscoelasticitywas investigated and discussed in the context of the known responseof anionically synthesized stars. Using a powerful characterizationtoolbox, including state-of-the-art interaction chromatography, rheometry,and tube modeling via the branch-on-branch (BoB) algorithm, we haveassessed the viscoelasticity of these star polymers quantitatively.In particular, we have demonstrated a variability in molecular structure,which differs substantially from their anionically synthesized counterparts.Hence, whereas this new family of star polymers is not recommendedfor fundamental studies of polymer physics such as the molecular originof relaxation mechanisms without prior extensive fractionation, theycould be used in studies of mixtures as well as industrially relevantprocessing operations that require large amounts of polymeric stars. [ABSTRACT FROM AUTHOR]

Periostin is a secreted extracellular matrix protein preferentially expressed in bone by osteocytes and periosteal osteoblasts. Reduced periostin expression may affect osteoblast differentiation and collagen type I synthesis and predispose to osteoporosis and increased fracture risk. We aimed to evaluate circulating periostin levels in postmenopausal women with low bone mass, their possible correlations with clinical and laboratory parameters, as well as the 3-month effect of zoledronic acid. Serum samples for periostin, 25-hydroxyvitamin D, parathyroid hormone (PTH), C-terminal telopeptide of type I collagen (CTx), and total alkaline phosphatase (tALP) were obtained from 46 postmenopausal women with low bone mass at baseline and 3 months after zoledronic acid infusion and from 30 agematched, postmenopausal controls with normal bone mass at baseline. There was no difference in periostin levels between women with normal and low bone mass (250 ± 15 vs. 272 ± 14 ng/ml, respectively; p = 0.279). Periostin remained essentially unchanged after zoledronic acid infusion (262 ± 18 ng/ml; p = 0.130). Serum periostin levels at baseline were not affected by previous bisphosphonate treatment, and were correlated only to tALP (rs = 0.351; p = 0.018). In multiple linear regression analysis, tALP (B = 3.17; 95 % CI = 0.59-5.79; p = 0.018) was associated with serum periostin levels at baseline, independently from previous anti-osteoporotic treatment, age, body mass index, and 25-hydroxyvitamin D. In conclusion, serum periostin levels do not differ between postmenopausal women with normal and low bone mass and are not affected by zoledronic acid treatment. Women with higher tALP have independently higher periostin levels. [ABSTRACT FROM AUTHOR]

The aim was to compare lean and overweight females in regard to the effects of eccentric exercise on muscle damage indices, resting energy expenditure (REE) and respiratory quotient (RQ) as well as blood lipid and lipoprotein profile. Lean and overweight females (deviated by their body mass index) performed an eccentric exercise session. Muscle damage, energy cost and lipid profile were assessed pre-exercise and up to 72 h post-exercise. After eccentric exercise (i) muscle damage indices were affected more in the overweight subjects compared with the lean subjects; (ii) the elevation of absolute and relative REE was larger and more prolonged in the overweight group compared with the lean group; (iii) after 24 h, RQ had significantly declined, with the overweight subjects exhibiting a larger reduction compared with the lean group; and (iv) the blood lipid profile was favorably modified, with the overweight group exhibiting more favorable responses compared with the lean group. The differences between the lean and the overweight subjects may be partly due to the fact that overweight individuals experienced greater muscle damage than lean individuals. Eccentric exercise may be a promising lifestyle factor to combat obesity and dyslipidemias. [ABSTRACT FROM AUTHOR]

Purpose. The objective of this study was to evaluate the diagnostic value of serum procalcitonin (PCT) in hemodialysis (HD) patients and its correlation to other traditional inflammatory markers. Methods. We measured plasma PCT levels in 120 patients on maintenance HD. PCT levels were compared with C-reactive protein (CRP), interleukin-6 (IL-6), prealbumin, and albumin. We also examined the above parameters subgroups, especially in diabetics and the elderly. Relations between parameters were studied by Spearman's correlation. Results. PCT concentrations were higher than the upper normal limit of 0.5 ng/mL in 38% of the patients. All patients with increased CRP had PCT concentrations higher than the upper normal limit. Plasma CRP concentrations were positively correlated to IL-6 ( r = 0.304). Prealbumin was negatively correlated with CRP ( r = 0.259) and with IL-6 ( r = 0.388). Conclusions. The combination of elevated IL-6 and CRP levels was associated with an altered nutritional status. The concomitant elevations in PCT, CRP, and IL-6 could be more sensitive in the evaluation of inflammation. [ABSTRACT FROM AUTHOR]

Objective: The clinical relevance of altered lymphocyte function and the possible relation with uremic toxins, such as parathyroid hormone (PTH) is not well understood. We studied the changes in cellular immunity in patients in hemodialysis (HD) therapy and examined the relationship between T-lymphocyte function and plasma levels of PTH. Patients and Methods: Thirty-four patients (14 male) were enrolled in this study (mean age: 63.20 ± 10.01 years, M ± SD, 12 h/week HD). Our study population was divided into two groups: 18 patients with increased levels of PTH and 16 patients with normal levels of PTH. Lymphocyte subsets (CD2 +, CD3 +, CD3 +/4 +, CD3 +/8 +, CD19 +, CD3-/16 + 56 +, CD4/CD8 ratio) were quantitated in both groups using monoclonal antibodies (Immunotech, Coulter) and flow cytometric analysis. Following analysis of variance (ANOVA) testing was performed to test differences between groups (SPSS version 10). Results: A significant increase of CD2 was noticed in patients with increased levels of PTH (84.8 ± 5.5 vs. 79.8 ± 4, p [ABSTRACT FROM AUTHOR]

BACKGROUND: We studied lymphocyte subset counts in comparison with normal subjects in order to clarify the abnormalities of cellular immune responses in uremic patients undergoing continuous ambulatory peritoneal dialysis(CAPD). METHODS: The study included 37 CAPD patients and 45 normal individuals, as the control group. For the study, CAPD patients were divided into four groups depending on duration of replacement therapy. Group I consisted of patients treated for 0–6 months(n = 6), group II for 6–12 months(n = 6), group III for 13–24 months(n = 16), and group IV for more than 25 months(n = 9). Flow cytometry was used for estimation of lymphocyte subsets(determination of CD2, CD3, CD3 +/CD4 +, CD3 +/CD8 +, CD3 −/16 + 56 +, CD19, CD4/CD8). RESULTS: Our patients started CAPD with decreased lymphocyte subset counts, slightly above the normal range(excluding CD3 −/16 + 56 +, CD2). After 6 months of CAPD therapy, an increase in CD4/CD8 ratio was observed and all examined lymphocyte subset counts decreased(excluding CD2). In patients on CAPD for more than 25 months, CD3 +/CD4 +, CD19 counts were below the normal range, CD3 −/16 + 56 + exceeded the upper limit of normal range and at the same time mean total lymphocyte count(TLC) was maintained in the normal range. CONCLUSIONS: We recommend lymphocyte subset determinations for detection of immune abnormalities in the course of CAPD treatment. [ABSTRACT FROM AUTHOR]

The assessment of glomerular filtration rate (GFR) is the most commonly used test of renal function. Cystatin-C, a cysteine protease inhibitor, which can be measured by light-scattering immunoassay, possesses many of the attributes required of the ideal GFR marker. Conversely, many endogenous markers that are widely used for the estimation of GFR such as serum creatinine (SCr) are not ideal. The present study was undertaken to evaluate the clinical application of serum cystatin-C (CysC) as a new marker of GFR in renal transplant patients.Eighteen patients (9 men) were enrolled in the study (mean age: 46.35, range: 31–67 years) to measure serum CysC levels and compare them, with SCr, creatinine clearance (CCr), as well as the Cockcroft-Gault equation (CG) or the MDRD as indicator of GFR. Spearman''s correlation coefficient was used to determine the relationship between CysC and other markers.There was a significant negative correlation between serum CysC and CCr (r = −0.768). Moreover, the CysC level was negatively correlated with CG (r = −0.854), positively correlated with SCr (r = 0.629), and negatively correlated with MDRD (r = −0.604).These results indicate that measurement of serum cystatin-C was useful and accurate to estimate GFR in renal transplant patients. The recent literature confirms our data although there are concerns about nonrenal influence on this test. Although serum CysC can generally be recommended as a marker for GFR, our study is still in progress seeking to validate the conclusions in a larger number of patients. [Copyright &y& Elsevier]

The comparative study of hemodialysis (HD) adequacy of Kt/V measurement between classic method (Daugirdas formula) and urea sensor monitor (online). 30 patients with end-stage renal failure undergoing dialysis were studied. A comparative evaluation of HD adequacy during the same session was done with two different methods: (1) blood samples were drawn in the beginning and in the end of HD session for the measurement of blood urea nitrogen (BUN) and after measurement of HD adequacy by 3rd generation Daugirdas formula and (2) urea sensor monitor use for continuous HD adequacy measurement during HD session. There was statistically significant correlation of Kt/V Daugirdas with Kt/V online (r = 0.8, p < 0.001). Also there was statistically significant correlation between solute removal index (SRI), Kt/V Daugirdas (r = 0.81, p < 0.001) and Kt/V online (r = 0.92, p < 0.001). From nutrition indices that were measured, the protein catabolic rate (PCR) had marginal negative correlation with the two compared adequacy indices, Kt/V Daugirdas (r = −0.24, p < 0.03), and Kt/V online (r = −0.17, p < 0.03) although the nPCR (normalized PCR) had marginal positive correlation (r = 0.35, p < 0.05) (r = 0.42, p < 0.05). The use of online urea sensor monitors contributes to the easy measurement of adequacy and nutrition indices and hence complicated mathematical formulas are not necessary. The results of these measurements are reliable and comparable with classic methods of HD adequacy evaluation. [ABSTRACT FROM AUTHOR]