Effects of resistance exercise training on acyl-ghrelin and obestatin levels in hemodialysis patients.

BACKGROUND: Patients undergoing hemodialysis (HD) present altered levels of appetite hormones such as acyl-ghrelin (orexigenic) and obestatin (anorexigenic), which may contribute to anorexia. Physical exercise may affect these hormones and improve appetite in these patients. OBJECTIVES: The objective of this study is to evaluate the effects of a resistance exercise program in appetite hormones, body composition, and nutritional status in HD patients. DESIGN: Intervention study with the control group. SUBJECTS: Fifty-two patients on regular HD program were enrolled into two groups: 37 patients performed exercises (56.7% male, 45 ± 12.8 years, 57 (9-192) months on HD) and 15 patients comprised the control group (66.7% men, 50 ± 10.6 years, 57 (11-153) months on HD). MEASUREMENTS: Exercise program (performed with elastic bands and ankle cuffs in both lower limbs) was supervised three times a week during 6 months (72 sessions). Patients had their blood drawn in a regular HD day after overnight fasting, before and after 6 months of exercise program. Obestatin, acyl-ghrelin, routine biochemical parameters, quality of life, and anthropometric data were collected and analyzed before and after 6 months. RESULTS: After 6 months of exercise, obestatin levels reduced [from 3.0 ng/mL (2.3-3.4) to 1.9 ng/mL (0.6-3.4)] and acyl-ghrelin levels increased [from 21.5 pg/mL (1.3-77.7) to 37.2 pg/mL (16.7-94.1)] and the control group presented no significant differences in both plasma levels of hormones. Body composition and physical functional assessed by SF-36 and albumin levels (3.7 ± 0.3 to 3.9 ± 0.2, p < 0.05) improved after exercises. CONCLUSION: Six months of resistance exercises contributed to changes in plasma appetite hormones, body composition, and nutritional status in hemodialysis patients.

New strategy to control cell migration and metastasis regulated by CCN2/CTGF.

Connective tissue growth factor (CTGF)/CCN family member 2 (CCN2) is a CCN family member of matricellular signaling modulators. It has been shown that CCN2/CTGF mediates cell adhesion, aggregation and migration in a large variety of cell types, including vascular endothelial cells, fibroblasts, epithelial cells, aortic smooth muscle and also pluripotent stem cells. Others matricellular proteins are capable of interacting with CCN2/CTGF to mediate its function. Cell migration is a key feature for tumor cell invasion and metastasis. CCN2/CTGF seems to be a prognostic marker for cancer. In addition, here we intend to discuss recent discoveries and a new strategy to develop therapies against CCN2/CTGF, in order to treat cancer metastasis.

Is there association between uric acid and inflammation in hemodialysis patients?

BACKGROUND: Elevated serum uric acid has been associated with a variety of cardiovascular disease and with inflammation, but these have been little explored in chronic kidney disease (CKD). Elevated uric acid levels are common in CKD patients and could be involved in inflammatory milieu; our aim was to analyze the association between uric acid and inflammatory markers in hemodialysis (HD) patients. DESIGN: This was a cross-sectional study. SETTING: This study was conducted from private clinic, Rio de Janeiro, Brazil. PATIENTS: This study included 50 HD patients and 21 healthy subjects. METHODS AND PROCEDURES: This study included 50 HD patients [62% men, 54.3 ± 12.6 years, 57.5 ± 50.1 months on dialysis, and body mass index (BMI), 24.4 ± 4.1 kg/m2] and 21 healthy individuals (45% men, 50.7 ± 15.7 years and BMI, 25.5 ± 4 kg/m2). Uric acid was measured using uricase-PAP method; inflammatory [tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), C-reactive protein (CRP)] and atherosclerosis markers [intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), monocyte chemoattractant protein-1 (MCP-1), plasminogen activator inhibitor-1 (PAI-1)] were measured by a multiplexed assay. RESULTS: PATIENTS presented high levels of TNF-α, IL-6, CRP, VCAM-1, ICAM-1 (5.5 ± 2.1 pg/mL, 4.1 ± 1.6 pg/mL, 0.32 ± 0.30 mg/mL, 48.5 ± 8.5 ng/mL, 20.5 ± 15.9 ng/mL, respectively), compared with healthy individuals (2.4 ± 1.1 pg/mL, 2.7 ± 0.4 pg/mL, 0.11 ± 0.12 mg/mL, 23.8 ± 5.5 ng/mL, 7.2 ± 1.2 ng/mL, respectively) ( p < 0.04). Uric acid levels were also higher in HD patients (5.4 ± 1.3 mg/dL) than in healthy individuals (3.9 ± 0.9 mg/dL) ( p < 0.02). There was a positive correlation between uric acid and inflammatory markers, IL-6 (r = 0.30, p = 0.01), CRP (r = 0.37, p = 0.003), TNF-α (r = 0.40, p = 0.001), ICAM-1 (r = 0.53, p = 0.0001), and VCAM-1 (r = 0.45, p = 0.0001). CONCLUSION: These original data suggest that uric acid may have a role in inflammation and atherosclerosis in HD patients. However, further prospective studies involving intervention trials should be conducted in order to search for actual causality relationship between these markers.

Reduced plasma zinc levels, lipid peroxidation, and inflammation biomarkers levels in hemodialysis patients: implications to cardiovascular mortality.

Despite the fact that low plasma zinc (Zn) levels play important roles in the oxidative stress, the relationships between lipid peroxidation and inflammation biomarkers with low plasma Zn levels have not been investigated in chronic kidney disease (CKD) patients. The aim of this study was to evaluate the Zn plasma levels, electronegative LDL [LDL(-)] levels, and inflammation markers as predictors of cardiovascular (CV) mortality in hemodialysis (HD) patients. Forty-five HD patients (28 men, 54.2 ± 12.7 years, 62.2 ± 51.4 months on dialysis and BMI 24.3 ± 4.1 kg/m(2)) were studied and compared to 20 healthy individuals (9 men, 51.6 ± 15.6 years, BMI 25.2 ± 3.9 kg/m(2)) and followed for 24 months to investigate the risks for CV mortality. LDL(-) levels were measured by ELISA, plasma Zn levels by atomic absorption spectrophotometry, C-reactive protein (CRP) level by immunoturbidimetric method, and tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), monocyte chemotactic protein-1 (MCP-1), and plasminogen activator inhibitor-1 (PAI-1) levels by a multiplex assay kit. HD patients presented low plasma Zn levels (54.9 ± 16.1 µg/dL) and high-LDL(-) (0.18 ± 0.12 U/L) and TNF-α (5.5 ± 2.2 pg/mL) levels when compared to healthy subjects (78.8 ± 9.4µ g/dL, 0.10 ± 0.08U/L, 2.4 ± 1.1 pg/mL, respectively, p < 0.05). Zn plasma levels were negatively correlated to TNF-α (r = -0.49; p = 0.0001) and LDL(-) (r = -0.33; p = 0.008). During the 2 years, 24.4% of the patients died, all due to CV disease. Analysis by the Cox model showed that high CRP, TNF-α, IL-6 levels, and long duration of HD were significant predictors of mortality. In conclusion, reduced Zn levels were associated with lipid peroxidation and inflammation, and we confirm here in a Brazilian cohort of HD patients that inflammation markers are strong predictors of CV death.

Association between circulating electronegative low-density lipoproteins and serum ferritin in hemodialysis patients: a pilot study.

BACKGROUND: Iron supplementation is a common recommendation to chronic kidney disease patients undergoing hemodialysis (HD). However, iron excess is closely associated with lipid peroxidation and, it is well known that electronegative low-density lipoproteins (LDL[-]) are present at higher plasma concentrations in diseases with high cardiovascular risk such as chronic kidney disease. Thus, the aim of this study was to investigate whether ferritin levels are associated with LDL(-) levels in HD patients. DESIGN: This was a cross-sectional study. SETTING: This study was conducted from a private clinic in Rio de Janeiro, Brazil. PATIENTS: The study included 27 HD patients and 15 healthy subjects. METHODS AND PROCEDURES: Twenty-seven HD patients (14 men, 58.6 ± 10 years, 62.2 ± 51.4 months on dialysis, and body mass index: 24.4 ± 4.2 kg/m(2)) were studied and compared with 15 healthy individuals (6 men, 53.8 ± 15.4 years, body mass index: 24.5 ± 4.3 kg/m(2)). Serum LDL(-) levels were measured using the enzyme-linked immunosorbent assay method; ferritin levels by commercially available kits, and tumor necrosis factor-α, interleukin-6, monocyte chemoattractant protein-1, and plasminogen activator inhibitor-1 were determined with a multiplex assay kit manufactured by R&D Systems. RESULTS: The HD patients presented higher LDL(-) and tumor necrosis factor-α levels (0.15 ± 0.13 U/L and 5.9 ± 2.3 pg/mL, respectively) than healthy subjects (0.07 ± 0.05 U/L and 2.3 ± 1.3 pg/mL, respectively) (P = .0001). The mean ferritin level in HD patients was 1,117.5 ± 610.4 ng/mL, and 90% of patients showed ferritin levels exceeding 500 ng/mL. We found a positive correlation between LDL(-) and ferritin in the patients (r = 0.48; P = .01), and ferritin was a significant contributor to LDL(-) concentrations independent of inflammation. CONCLUSIONS: Excess body iron stores for HD patients was associated with signs of increased oxidative stress, as reflected by increased LDL(-) levels in HD patients.

Alpha-tocopherol supplementation decreases electronegative low-density lipoprotein concentration [LDL(-)] in haemodialysis patients.

BACKGROUND: Oxidative stress is a significant contributor to cardiovascular diseases (CVD) in haemodialysis (HD) patients, predisposing to the generation of oxidized low-density lipoprotein (oxLDL) or electronegatively charged LDL subfraction. Antioxidant therapy such as alpha-tocopherol acts as a scavenger of lipid peroxyl radicals attenuating the oxidative stress, which decreases the formation of oxLDL. The present study was designed to investigate the influence of the alpha-tocopherol supplementation on the concentration of electronegative low-density lipoprotein [LDL(-)], a minimally oxidized LDL, which we have previously described to be high in HD patients. METHODS: Blood samples were collected before and after 120 days of supplementation by alpha-tocopherol (400 UI/day) in 19 stable HD patients (50 +/- 7.8 years; 9 males). The concentrations of LDL(-) in blood plasma [using an anti-LDL- human monoclonal antibody (mAb)] and the anti-LDL(-) IgG auto-antibodies were determined by ELISA. Calculation of body mass index (BMI) and measurements of waist circumference (WC), triceps skin folds (TSF) and arm muscle area (AMA) were performed. RESULTS: The plasma alpha-tocopherol levels increased from 7.9 microM (0.32-18.4) to 14.2 microM (1.22-23.8) after the supplementation (P = 0.02). The mean concentration of LDL(-) was reduced from 570.9 microg/mL (225.6-1241.0) to 169.1 microg/mL (63.6-621.1) (P < 0.001). The anti-LDL(-) IgG auto-antibodies did not change significantly after the supplementation. The alpha-tocopherol supplementation also reduced the total cholesterol and LDL-C levels in these patients, from 176 +/- 42.3 mg/dL to 120 +/- 35.7 mg/dL (P < 0.05) and 115.5 +/- 21.4 mg/dL to 98.5 +/- 23.01 mg/dL (P < 0.001), respectively. CONCLUSION: The oral administration of alpha-tocopherol in HD patients resulted in a significant decrease in the LDL(-), total cholesterol and LDL-C levels. This effect may favour a reduction in cardiovascular risk in these patients, but a larger study is required to confirm an effect in this clinical setting.

Chronic Periodontitis and RANKL/OPG Ratio in Peri-Implant Mucosae Inflammation.

tHistory of chronic periodontitis (CP) is a risk factor for oseointegration failure. The osteoclastogenesis system (RANK, RANKL and OPG) is critical for bone homeostatic control. We investigated the levels of OPG and RANKL in peri-implant tissues from volunteers with and without a history of CP and their association with mucosae inflammation. This is a single-blind case-contro study. Diagnosis of a history of CP and peri-implant examination was performed on 46 volunteers, divided into control (without history of CP, n=26) and CP group (with history of CP, n=20). Gingival biopsies were harvested during implant exposure. Quantitative PCR evaluated OPG/RANKL mRNA expressions. OPG and RANKL proteins were analyzed by western blot and immunohistochemistry assay. The chi-square test analyzed the significance of nominal variables between groups while continuous variables were analyzed by T-test or Mann-Whitney test, after Shapiro-Wilk test evaluation. The 2-ΔΔCT Livak method calculation evaluated the gene expression. Values of p<0.05 were considered statistically significant. Volunteers with CP history had 23 times higher chance of developing mucosae inflammation. High mucosae levels of RANKL (p=0.04) and RANKL/OPG (p=0.001) mRNA expressions were observed in CP group. CP volunteers showed increased RANKL protein levels in opposition to decreased OPG expression. Even without active periodontitis, volunteers with a history of CP had elevated gingival levels of RANKL/OPG and higher correlation with peri-implant mucosae inflammation and implant loss.

Use of tranexamic acid for controlling bleeding in thoracolumbar scoliosis surgery with posterior instrumentation.

OBJECTIVE: Scoliosis surgery involves major blood loss and frequently requires blood transfusion. The cost and risks involved in using allogeneic blood have motivated investigation of methods capable of reducing patients' bleeding during operations. One of these methods is to use antifibrinolytic drugs, and tranexamic acid is among these. The aim of this study was to assess the use of this drug for controlling bleeding in surgery to treat idiopathic scoliosis. METHODS: This was a retrospective study in which the medical files of 40 patients who underwent thoracolumbar arthrodesis by means of a posterior route were analyzed. Of these cases, 21 used tranexamic acid and were placed in the test group. The others were placed in the control group. The mean volumes of bleeding during and after the operation and the need for blood transfusion were compared between the two groups. RESULTS: The group that used tranexamic acid had significantly less bleeding during the operation than the control group. There was no significant difference between the groups regarding postoperative bleeding and the need for blood transfusion. CONCLUSIONS: Tranexamic acid was effective in reducing bleeding during the operation, as demonstrated in other studies. The correlation between its use and the reduction in the need for blood transfusion is multifactorial and could not be established in this study. We believe that tranexamic acid may be a useful resource and that it deserves greater attention in randomized double-blind prospective series, with proper control over variables that directly influence blood loss.

OBJETIVO: A cirurgia de escoliose envolve elevada perda sanguínea e necessita frequentemente de hemotransfusão. O custo e os riscos envolvidos no uso do sangue alogênico têm motivado pesquisas de métodos capazes de reduzir o sangramento operatório nos pacientes. Um desses métodos é o uso de drogas antifibrinolíticas, entre as quais está o ácido tranexâmico (ATX). O objetivo deste estudo foi verificar o uso dessa droga no controle do sangramento em cirurgias de escoliose idiopática. MÉTODOS: Estudo retrospectivo no qual foram analisados os prontuários de 40 pacientes submetidos à artrodese toracolombar por via posterior. Desses, apenas 21 usaram o ATX e foram relacionados no grupo teste. Os demais foram relacionados no grupo controle. Foram comparadas as médias de sangramento per e pós-operatório e a necessidade de hemotransfusão entre os dois grupos. RESULTADOS: O grupo que usou o ATX teve sangramento peroperatório significativamente menor do que o grupo controle. Não houve diferença significativa entre os grupos para o sangramento pós-operatório e a necessidade de hemotransfusão. CONCLUSÕES: O ATX foi eficaz na redução do sangramento peroperatório, conforme demostrado em outros estudos. A correlação entre o seu uso e a redução da necessidade de hemotransfusão é multifatorial e não pôde ser estabelecida neste trabalho. Acreditamos que o ácido tranexâmico possa ser um recurso útil e merece maior atenção em séries prospectivas, duplo-cegas, randomizadas, com o devido controle das variáveis que interferem diretamente na perda sanguínea.

Fructose intake: is there an association with uric acid levels in nondialysis-dependent chronic kidney disease patients?

INTRODUCTION: Fructose intake has increased dramatically in consequence of the consumption of fructose-based sweetened foods and beverages. Research suggests that high fructose intake has a strong association with uric acid (UA) levels and worse prognosis of chronic kidney disease (CKD). OBJECTIVE: The aim of this study was to investigate the influence of fructose intake on plasma UA levels in nondialysis- dependent CKD patients. METHODS: Fifty-two patients on stages 3-5 (64.2 ± 9.6 years, 24 men, glomerular filtration rate of 30.5 ± 10.3 ml/ min) were divided into two groups: high fructose intake (>50 g/d, n=29, 61.7 ± 9.3 years) and low fructose intake (

Introducción: El consumo de fructosa ha aumentado dramáticamente en consecuencia del consumo de alimentos y bebidas azucaradas a base de fructosa. Pesquisas sugieren que el alto consumo de fructosa tiene una fuerte asociación con niveles de ácido úrico (AU) y empeora el pronóstico de la enfermedad renal crónica (ERC). Objetivo: El objetivo de este estudio fue investigar la influencia del consumo de fructosa en los niveles plasmáticos de ácido úrico en pacientes con ERC que no son dependiente de diálisis. Métodos: Cincuenta y dos pacientes en fases 3-5 (64,2±9,6 años, 24 hombres, tasa de filtración glomerular de 30,5±10,3ml/min) se dividieron en dos grupos: alto consumo de fructosa (>50g/día, n=29, 61,7± 9,3 años) y bajo consumo de fructosa (

Is there association between acyl-ghrelin and inflammation in hemodialysis patients?

INTRODUCTION AND OBJECTIVES: Patients with chronic kidney disease (CKD) present anorexia, which may be related with the chronic inflammatory process. Thus the objective of this study was to evaluate if there is association between inflammation and the orexigenic hormone, acyl-ghrelin, in CKD patients undergoing hemodialysis (HD). METHODS: Thirty-six patients were studied (61.1% men, 46.7 ± 14.9 years, BMI 22.9 ± 3.9 kg/m²) in regular HD program (65.0 ± 46.8 months). Plasma levels of acyl-ghrelin and inflammatory markers TNF-α, IL-6 and CRP were measured by enzyme immunoassay (ELI-SA, Enzyme Linked Immunosorbent Assay). Anthropometric parameters were collected for assessment of nutritional status and dietary intake was assessed by food recall. RESULTS: The patients presented elevated plasma levels of IL-6 (83 ± 10 pg/mL), TNF-α (21.06 pg/mL [20.6-40.0]) and CRP (2.7 pg/mL [1.73.4]) compared to normal values. Acylghrelin plasma levels were (18.0 [1.3 to 77.7 pg/mL]) low when compared to healthy individuals. However, patients with high BMI (> 25 kg/m²) presented lower acyl-ghrelin plasma levels (13.6 [1.3 to 30.5] pg/mL) when compared to patients with BMI < 25 kg/m² (21.7 [7.4 to 77.7] pg/mL) (p < 0.05). Acylghrelin and BMI were negatively correlated (r = -0.38, p = 0.02) and there was no significant correlation between acyl-ghrelin and inflammatory markers. CONCLUSIONS: Hemodialysis patients showed low acyl-ghrelin levels and seem to present an acyl-ghrelin resistance and there was no correlation between inflammation and this orexigenic hormone.

Chronic Periodontitis and RANKL/OPG Ratio in Peri-Implant Mucosae Inflammation

Abstract tHistory of chronic periodontitis (CP) is a risk factor for oseointegration failure. The osteoclastogenesis system (RANK, RANKL and OPG) is critical for bone homeostatic control. We investigated the levels of OPG and RANKL in peri-implant tissues from volunteers with and without a history of CP and their association with mucosae inflammation. This is a single-blind case-contro study. Diagnosis of a history of CP and peri-implant examination was performed on 46 volunteers, divided into control (without history of CP, n=26) and CP group (with history of CP, n=20). Gingival biopsies were harvested during implant exposure. Quantitative PCR evaluated OPG/RANKL mRNA expressions. OPG and RANKL proteins were analyzed by western blot and immunohistochemistry assay. The chi-square test analyzed the significance of nominal variables between groups while continuous variables were analyzed by T-test or Mann-Whitney test, after Shapiro-Wilk test evaluation. The 2-ΔΔCT Livak method calculation evaluated the gene expression. Values of p<0.05 were considered statistically significant. Volunteers with CP history had 23 times higher chance of developing mucosae inflammation. High mucosae levels of RANKL (p=0.04) and RANKL/OPG (p=0.001) mRNA expressions were observed in CP group. CP volunteers showed increased RANKL protein levels in opposition to decreased OPG expression. Even without active periodontitis, volunteers with a history of CP had elevated gingival levels of RANKL/OPG and higher correlation with peri-implant mucosae inflammation and implant loss.

Resumo A história de periodontite crônica (CP) é um fator de risco para falhas na osseointegração. O sistema de osteoclastogênese (RANK, RANKL e OPG) é crucial para o controle da homeostase óssea. O objetivo deste estudo foi investigar os níveis de OPG e RANKL no tecido peri-implantar de voluntários com e sem histórico de CP e sua associação com inflamação da mucosa. Este é um estudo tipo caso-controle. O exame para diagnóstico de CP e na região peri-implantar foi realizado em 46 voluntários, divididos em controle (sem história CP, n=26) e grupo CP (com histórico de CP, n=20). Descartes gengivais foram obtidos durante a exposição do implante. PCR quantitativo avaliou a expressão do RNAm de OPG/RANKL. As proteínas OPG e RANKL foram analisadas por western blot e imunohistoquímica. O teste do qui-quadrado analisou a significância entre as variáveis nominais enquanto as variáveis contínuas foram analisadas pelo teste-t e Mann-Whitney, após o teste de Shapiro-wilk. O método do Livak 2--ΔΔCT avaliou a expressão gênica. Os voluntários com CP apresentaram 23 vezes mais chances de desenvolver inflamação da mucosa. Expressão elevada no RNAm de RANKL (p=0.04) e RANKL/OPG (p=0.001) foram observadas no grupo CP. Voluntários com CP mostraram aumento dos níveis da proteína RANKL em contraste com diminuída expressão de OPG. Mesmo sem periodontite ativa, voluntários com histórico de CP apresentaram elevado nível gengival de RANKL/OPG e alta correlação com inflamação peri-implantar e perda do implante.

Linking zinc and leptin in chronic kidney disease: future directions.

Anorexia is a common complication in patients with chronic kidney disease (CKD) and is associated with the development of malnutrition and an increased risk of mortality. Several compounds are linked to anorexia in these patients; however, the mechanisms are unknown. Zinc (Zn) deficiency is associated with decreased food intake and has been observed in CKD patients. In addition, leptin is an anorexigenic peptide, and patients with CKD present generally high levels of this hormone. Studies have suggested an association between Zn and leptin status in human and rats; however, the results are inconsistent. Some claimed that Zn supplementation does not change leptin release or that there is no significant relationship between Zn and leptin. Others have reported that Zn might be a mediator of leptin production. CKD patients have hyperleptinemia and hypozincemia, but the relationship between Zn deficiency and leptin levels in CKD patients has been poorly understood until now. The aim of this review is to integrate knowledge on leptin and Zn actions to provide a cohesive clinical perspective regarding their interactions in CKD patients.

Relationship between zinc levels and plasma leptin in hemodialysis patients.

UNLABELLED: Recent evidences suggested a possible relationship between zinc deficiency and leptin levels in pathogenesis of anorexia in chronic kidney disease. The present study addressed the relationship between zinc and leptin in hemodialysis (HD) patients. METHODS: Fifty HD patients (54.3±12.7years old, 62% men) were studied and compared to 21 healthy volunteers (50.7±15.7years old, 43% men). Biochemical data, serum zinc, plasma leptin, IL-6, TNF-α and C-Reactive Protein levels were determined. Anthropometric parameters, food intake and appetite score were also assessed. RESULTS: The leptin levels were higher in HD patients (16.1µg/mL (0.21-118.25) vs 6.0µg/mL (0.50-23.10)) in healthy volunteers (p=0.04), whereas serum zinc levels were lower (54.5±16.3µg/dL) compared to healthy volunteers (78.4±9.4µg/dL) (p=0.0001). The plasma leptin was correlated negatively with plasma zinc (r=-0.33; p=0.007), energy (r=-0.38; p=0.002) and protein intake (r=-0.34; p=0.006) and, positively correlated with BMI (r=0.54; p=0.0001), % body fat (r=0.70; p=0.0001) and conicity index (r=0.46; p=0.001). Plasma zinc was associated with hemoglobin (r=0.30; p=0.04) and negatively associated with TNF-α (r=-0.37; p=0.002) and C-Reactive Protein (r=-0.37; p=0.004). There was no correlation among Zn, leptin and appetite score in these patients. CONCLUSION: This study showed that low plasma zinc levels are negatively associated with high leptin levels in HD patients.

Increased electronegative LDL and decreased antibodies against electronegative LDL levels correlate with inflammatory markers and adhesion molecules in hemodialysed patients.

BACKGROUND: Chronic Kidney Disease (CKD) patients present high levels of electronegative LDL (LDL-) that can modulate the expression of molecules involved in inflammation and it is closely linked to atherosclerosis. We investigated the association between LDL(-) and inflammatory markers in patients undergoing hemodialysis (HD). METHODS: Forty-seven HD patients from a private clinic in Rio de Janeiro, Brazil were studied and compared with 20 age matched healthy individuals. Serum LDL(-) and anti-LDL(-) autoantibody levels were measured by ELISA; TNF-α, IL-6, VCAM-1 and ICAM-1 were determined by a multiplex assay kit. RESULTS: HD patients presented higher IL-6 and TNF-α concentrations (4.1 ± 1.6 and 5.5 ± 2.1 pg/ml, respectively) than healthy subjects (2.6 ± 0.2 and 2.4 ± 1.1 pg/ml, respectively) (p=0.0001). In addition, they presented higher VCAM-1 and ICAM-1 levels and, LDL(-) concentrations were also increased (0.18 ± 0.12 U/l) when compared to healthy individuals (0.10 ± 0.08 U/l) (p<0.02). In contrast, the anti-LDL(-) autoantibody levels were lower in HD patients (0.02 ± 0.01 mg/l) than in healthy subjects (0.05 ± 0.03 mg/l) (p<0.001). There was a positive correlation between LDL(-) and IL-6 (r=0.25, p=0.004) and ICAM-1 (r=0.36; p=0.003). There was also a negative correlation between anti-LDL(-) autoantibodies and TNF-α (r=-0.37; p=0.003) and VCAM-1 (r=-0.50; p=0.0001). CONCLUSIONS: The association between LDL(-) and inflammation and the lower levels of anti-LDL(-) autoantibodies are important risk factors related to atherosclerosis in CKD.

Zinc deficiency in chronic kidney disease: is there a relationship with adipose tissue and atherosclerosis?

Cardiovascular complications caused by an accelerated atherosclerotic disease consist the major cause of morbidity and mortality in patients with chronic kidney disease (CKD). These patients present multiple atherosclerotic risk factors, considered traditional, as well as nontraditional risk factors such as inflammation and oxidative stress. These complications are also seen in obesity, in which endothelial dysfunction is one of the early stages of atherosclerosis. The impact of trace metal deficiencies on this process is not well studied in patients with CKD and in obese people, although the influence of trace elements depletion, particularly zinc (Zn), may have significant clinical implications. This brief review describes the functions of Zn as well as the respective role of this trace element in atherosclerosis processes, with a particular emphasis on obese patients with chronic kidney disease.

Use of tranexamic acid for controlling bleeding in thoracolumbar scoliosis surgery with posterior instrumentation / Uso do ácido tranexâmico no controle do sangramento em cirurgias de escoliose toracolombar com instrumentação posterior

OBJECTIVE: Scoliosis surgery involves major blood loss and frequently requires blood transfusion. The cost and risks involved in using allogeneic blood have motivated investigation of methods capable of reducing patients' bleeding during operations. One of these methods is to use antifibrinolytic drugs, and tranexamic acid is among these. The aim of this study was to assess the use of this drug for controlling bleeding in surgery to treat idiopathic scoliosis. METHODS: This was a retrospective study in which the medical files of 40 patients who underwent thoracolumbar arthrodesis by means of a posterior route were analyzed. Of these cases, 21 used tranexamic acid and were placed in the test group. The others were placed in the control group. The mean volumes of bleeding during and after the operation and the need for blood transfusion were compared between the two groups. RESULTS: The group that used tranexamic acid had significantly less bleeding during the operation than the control group. There was no significant difference between the groups regarding postoperative bleeding and the need for blood transfusion. CONCLUSIONS: Tranexamic acid was effective in reducing bleeding during the operation, as demonstrated in other studies. The correlation between its use and the reduction in the need for blood transfusion is multifactorial and could not be established in this study. We believe that tranexamic acid may be a useful resource and that it deserves greater attention in randomized double-blind prospective series, with proper control over variables that directly influence blood loss. .

OBJETIVO: A cirurgia de escoliose envolve elevada perda sanguínea e necessita frequentemente de hemotransfusão. O custo e os riscos envolvidos no uso do sangue alogênico têm motivado pesquisas de métodos capazes de reduzir o sangramento operatório nos pacientes. Um desses métodos é o uso de drogas antifibrinolíticas, entre as quais está o ácido tranexâmico (ATX). O objetivo deste estudo foi verificar o uso dessa droga no controle do sangramento em cirurgias de escoliose idiopática. MÉTODOS: Estudo retrospectivo no qual foram analisados os prontuários de 40 pacientes submetidos à artrodese toracolombar por via posterior. Desses, apenas 21 usaram o ATX e foram relacionados no grupo teste. Os demais foram relacionados no grupo controle. Foram comparadas as médias de sangramento per e pós-operatório e a necessidade de hemotransfusão entre os dois grupos. RESULTADOS: O grupo que usou o ATX teve sangramento peroperatório significativamente menor do que o grupo controle. Não houve diferença significativa entre os grupos para o sangramento pós-operatório e a necessidade de hemotransfusão. CONCLUSÕES: O ATX foi eficaz na redução do sangramento peroperatório, conforme demostrado em outros estudos. A correlação entre o seu uso e a redução da necessidade de hemotransfusão é multifatorial e não pôde ser estabelecida neste trabalho. Acreditamos que o ácido tranexâmico possa ser um recurso útil e merece maior atenção em séries prospectivas, duplo-cegas, randomizadas, com o devido controle das variáveis que interferem diretamente na perda sanguínea. .

Há associação entre acyl-grelina e inflamação em pacientes em hemodiálise? / Is there association between acyl-ghrelin and inflammation in hemodialysis patients?

INTRODUÇÃO E OBJETIVOS: Pacientes com doença renal crônica (DRC) apresentam um quadro de anorexia que pode estar relacionado com o processo inflamatório crônico, característico desta população. Assim, o presente estudo teve como objetivo avaliar se há associação entre inflamação e o hormônio orexígeno, acyl-grelina, em pacientes com DRC em hemodiálise (HD). MÉTODOS: Foram estudados 36 pacientes (61,1% homens; 46,7 ± 14,9 anos; IMC 22,9 ± 3,9 kg/m²) em programa regular de HD (65,0 ± 46,8 meses em HD). Os níveis plasmáticos de acyl-grelina e dos marcadores inflamatórios (TNF-α, IL-6 e PCR) foram medidos com o uso do método imunoenzimático (ELISA, Enzyme Linked Immunosorbent Assay). Dados antropométricos foram coletados para avaliação do estado nutricional e a ingestão alimentar foi analisada por meio de recordatório alimentar de 24h de 2 dias. RESULTADOS: Os pacientes apresentaram elevados níveis de IL-6 (83 ± 10 pg/mL), TNF-α (21,06 pg/mL [20,6-40,0]) e PCR (2,7 pg/mL [1,7-3,4]) quando comparados a valores normais. Os níveis plasmáticos de acyl-grelina (18,0 pg/mL [1,3-77,7 pg/mL]) foram baixos comparados com valores de indivíduos saudáveis. Porém, pacientes com elevado IMC (> 25 kg/m²) apresentaram menores concentrações plasmáticas de acyl-grelina (13,6 [1,3-30,5] pg/mL) em relação aos pacientes com IMC < 25 kg/m² (21,7 [7,4-77,7] pg/mL (p < 0,05). Houve correlação negativa entre o IMC e acyl-grelina (r = -0,38; p = 0,02), porém, não houve correlação significativa entre acyl-grelina e os marcadores inflamatórios. CONCLUSÃO: Apesar dos pacientes em HD apresentarem baixas concentrações de acyl-grelina e uma provável resistência a este hormônio, não houve associação entre inflamação e acyl-grelina.

INTRODUCTION AND OBJECTIVES: Patients with chronic kidney disease (CKD) present anorexia, which may be related with the chronic inflammatory process. Thus the objective of this study was to evaluate if there is association between inflammation and the orexigenic hormone, acyl-ghrelin, in CKD patients undergoing hemodialysis (HD). METHODS: Thirty-six patients were studied (61.1% men, 46.7 ± 14.9 years, BMI 22.9 ± 3.9 kg/m²) in regular HD program (65.0 ± 46.8 months). Plasma levels of acyl-ghrelin and inflammatory markers TNF-α, IL-6 and CRP were measured by enzyme immunoassay (ELI-SA, Enzyme Linked Immunosorbent Assay). Anthropometric parameters were collected for assessment of nutritional status and dietary intake was assessed by food recall. RESULTS: The patients presented elevated plasma levels of IL-6 (83 ± 10 pg/mL), TNF-α (21.06 pg/mL [20.6-40.0]) and CRP (2.7 pg/mL [1.73.4]) compared to normal values. Acylghrelin plasma levels were (18.0 [1.3 to 77.7 pg/mL]) low when compared to healthy individuals. However, patients with high BMI (> 25 kg/m²) presented lower acyl-ghrelin plasma levels (13.6 [1.3 to 30.5] pg/mL) when compared to patients with BMI < 25 kg/m² (21.7 [7.4 to 77.7] pg/mL) (p < 0.05). Acylghrelin and BMI were negatively correlated (r = -0.38, p = 0.02) and there was no significant correlation between acyl-ghrelin and inflammatory markers. CONCLUSIONS: Hemodialysis patients showed low acyl-ghrelin levels and seem to present an acyl-ghrelin resistance and there was no correlation between inflammation and this orexigenic hormone.

Fatores relacionados à força de preensão manual de pacientes submetidos à hemodiálise: ênfase na anemia / Factors related to handgrip strength in patients undergoing hemodialysis: emphasis on anemia

Anemia is a frequent comorbidity in patients undergoing hemodialysis and is associated with reduced functional capacity. Thus, it possible to assume that anemia can also impair muscle strength in these patients. The aim of this study was to assess whether there is an association between handgrip strength and anemia in patients undergoing hemodialysis. Fifty five patients on regular hemodialysis program (aged 49.0±14.0, 38 men) were studied. Handgrip strength, assessed by manual dynamometry, was measured in the arm without vascular access functioning after the dialysis session, being considered impaired when values were lower than the 10th percentile of age and gender specific values btained from an urban population in Rio de Janeiro. Biochemical data and body composition were also evaluated. Sixty-two percent of patients presented anemia and 34.5% showed handgrip strength compromised. The handgrip strength was positively correlated with height, body weight, body mass index, waist circumference, corrected arm muscle area and fat-free mass; and negatively correlated with age and dialysis efficiency. Hemoglobin and hematocrit were not correlated with handgrip strength and they did not differ between patients with preserved handgrip strength and those with handgrip strength compromised. Thus, anemia did not exert influence on the handgrip strength in patients undergoing hemodialysis, which reinforces the use of manual dynamometry as a reliable method for the assessment of nutritional status in this population.

La anemia es una comorbilidad frecuente en pacientes sometidos a hemodiálisis y se asocia con una capacidad funcional reducida. Por lo tanto, podemos suponer que la anemia también puede comprometer la fuerza muscular en esos pacientes. El objetivo de este estudio fue evaluar si existe una asociación entre la fuerza de prensión manual y el estado de anemia en pacientes sometidos a hemodiálisis. Se estudiaron 55 pacientes en tratamiento regular de hemodiálisis (49,0±14,0 años de edad, 38 hombres). Se midió, por dinamometría, la fuerza prensil manual en un brazo sin acceso vascular funcional después de la sesión de hemodiálisis. Se consideró que la fuerza prensil se encontraba perjudicada cuando los valores fueron inferiores al 10% del valor correspondiente a sexo y edad, tomando como valores de referencia los obtenidos para la población urbana de Río de Janeiro. Se evaluaron, asimismo, los datos bioquímicos y de composición corporal. El sesenta y dos por ciento de los pacientes tenía anemia y 34,5% presentó fuerza prensil comprometida. La fuerza de prensión manual se correlacionó positivamente con la altura, el peso corporal, el índice de masa corporal, la circunferencia de la cintura, el área muscular del brazo corregida y la masa libre de grasa. Se observó correlación negativa entre la fuerza de prensil manual, la edad y la eficacia de la diálisis. La cantidad de hemoglobina y el hematocrito fueron semejantes entre los pacientes con fuerza prensil normal y comprometida pero no se correlacionaron con la misma Se concluye que la anemia no tuvo ninguna influencia en la fuerza de pensión manual en los pacientes sometidos a hemodiálisis, lo que refuerza el uso de la dinamometría manual como método confiable para la evaluación del estado nutricional de esa población.

A anemia é uma comorbidade frequente em pacientes submetidos à hemodiálise e está associada à redução da capacidade funcional. Desta forma, podemos supor que a anemia é capaz também de comprometer a força muscular destes pacientes. O objetivo deste estudo foi avaliar se há associação entre força de preensão manual e o estado de anemia em pacientes submetidos à hemodiálise. Foram estudados 55 pacientes em programa regular de hemodiálise (49,0±14,0 anos de idade, 38 homens). A força de preensão manual, avaliada através de dinamometria manual, foi aferida no braço sem acesso vascular funcionante após a sessão de hemodiálise, sendo considerada comprometida quando os valores foram inferiores ao percentil 10 correspondente, segundo gênero e idade, aos valores de referência obtidos para população urbana do RJ. Dados bioquímicos e de composição corporal também foram avaliados. Sessenta e dois por cento dos pacientes apresentaram anemia e 34,5% exibiram força de preensão manual comprometida. A força de preensão manual apresentou correlação positiva com a estatura, peso corporal, índice de massa corporal, circunferência da cintura, área muscular do braço corrigida e massa livre de gordura e correlação negativa com idade e eficiência dialítica. A hemoglobina e hematócrito não se correlacionaram com força de preensão manual e não diferiram entre os pacientes com força de preensão manual preservada e comprometida. Conclui-se que a anemia não exerceu influência sobre a força de preensão manual de pacientes submetidos à hemodiálise, o que reforça o uso da dinamometria manual como método confiável para avaliação do estado nutricional nesta população.