Inquérito Brasileiro de Diálise Crônica 2013 - Análise das tendências entre 2011 e 2013 / Brazilian Chronic Dialysis Survey 2013 - Trend analysis between 2011 and 2013

Introdução: Dados nacionais sobre diálise crônica têm tido impacto no planejamento do tratamento. Objetivo: Apresentar dados do inquérito da Sociedade Brasileira de Nefrologia sobre os pacientes com doença renal crônica em tratamento dialítico em julho de 2013 e comparar com dados de 2011- 12. Métodos: Levantamento de dados de unidades de diálise do país. A coleta de dados foi feita utilizando questionário preenchido on-line pelas unidades de diálise. Resultados: Trezentos e trinta e quatro (51%) unidades responderam ao inquérito. Em julho de 2013, o número total estimado de pacientes em diálise foi de 100.397. As estimativas nacionais das taxas de prevalência e de incidência de tratamento dialítico foram de 499 (variação: 284 na região Norte e 622 na Sul) e 170 pacientes por milhão da população, respectivamente. O número estimado de pacientes que iniciaram tratamento em 2013 foi 34.161. A taxa anual de mortalidade bruta foi de 17,9%. Dos pacientes prevalentes, 31,4% tinham idade ≥ 65 anos, 90,8% estavam em hemodiálise e 9,2% em diálise peritoneal, 31.351 (31,2%) estavam em fila de espera para transplante, 30% tinham diabetes, 17% tinham PTH > 600 pg/ml e 23% hemoglobina < 10 g/dl. Cateter venoso era usado como acesso em 15,4% dos pacientes em hemodiálise. Conclusão: O número absoluto de pacientes em diálise tem aumentado 3% ao ano nos últimos 3 anos. As taxas de prevalência e incidência de pacientes em diálise ficaram estáveis, e a taxa de mortalidade tendeu a diminuir em relação a 2012. Houve tendência a melhor controle da anemia e dos níveis de PTH. .

Introduction: National chronic dialysis data have had impact in the treatment planning. Objective: To report data of the annual survey of the Brazilian Society of Nephrology about chronic kidney disease patients on dialysis in July 2013 and compare with 2011-12. Methods: A survey based on data of dialysis units from the whole country. The data collection was performed by using a questionnaire filled out on-line by the dialysis units. Results: Three hundred thirty four (51%) of the dialysis units in the country answered the questionnaire. In July 2013, the total estimated number of patients on dialysis was 100,397. The estimated prevalence and incidence rates of chronic maintenance dialysis were 449 (range: 284 in the North region and 622 in the South) and 170 patients per million population, respectively. The estimated number of new patients starting dialysis in 2013 was 34,161. The annual gross mortality rate was 17.9%. For prevalent patients, 31.4% were aged 65 years or older, 90.8% were on hemodialysis and 9.2% on peritoneal dialysis, 31,351 (31.2%) were on a waiting list of renal transplant, 30% were diabetics, 17% had PTH levels > 600 pg/ml and 23% hemoglobin < 10 g/ dl. A venous catheter was the vascular access for 15.4% of the hemodialysis patients. Conclusion: The absolute number of patients on dialysis has increased 3% per year. The prevalence and incidence rates of patients on dialysis leveled off, while the mortality rate tended to decrease compared with 2012. There was a trend towards a better control of the anemia and PTH levels. .

Effect of Advanced Glycation End Products on Oxidative Stress and Senescence of Trabecular Meshwork Cells

PURPOSE: To investigate the effect of advanced glycation end products (AGE) on oxidative stress and cellular senescence in cultured human trabecular meshwork cells (HTMC). METHODS: Primarily cultured HTMC were exposed to 0, 10, 50, 100, 200 microg/mL of glycated bovine serum albumin (G-BSA) for 5 days. Also co-exposed were L-arginine, sepiapterin, and antioxidant N-acetylcysteine (NAC). Cellular survival and production of nitric oxide (NO), superoxide, and reactive oxygen species were assessed by 3-[4, 5-dimethylthiazol-2-yl]-2, 5-diphenyltetrazolium bromide assay, Griess assay, cytochrome c assay, and dichlorofluorescin diacetate assay, respectively. Senescence-associated beta-galactosidase staining was performed to quantify the degree of cellular senescence. RESULTS: G-BSA decreased cellular survival, NO production, and increased superoxide production significantly in a dose-dependent manner. The effects of G-BSA were abolished with co-exposure of L-arginine, sepiapterin, and NAC. G-BSA enhanced cellular senescence accompanied by increased production of reactive oxygen species. G-BSA-induced cellular senescence was suppressed by application of L-arginine, sepiapterin, and NAC. CONCLUSIONS: AGE enhances cellular senescence of HTMC accompanied with increased oxidative stress. AGE-induced oxidative stress and cellular senescence could be delayed by application of anti-oxidants.

Gamma-tocotrienol modulation of senescence-associated gene expression prevents cellular aging in human diploid fibroblasts

OBJECTIVE: Human diploid fibroblasts undergo a limited number of cellular divisions in culture and progressively reach a state of irreversible growth arrest, a process termed cellular aging. The beneficial effects of vitamin E in aging have been established, but studies to determine the mechanisms of these effects are ongoing. This study determined the molecular mechanism of γ-tocotrienol, a vitamin E homolog, in the prevention of cellular aging in human diploid fibroblasts using the expression of senescence-associated genes. METHODS: Primary cultures of young, pre-senescent, and senescent fibroblast cells were incubated with γ-tocotrienol for 24 h. The expression levels of ELN, COL1A1, MMP1, CCND1, RB1, and IL6 genes were determined using the quantitative real-time polymerase chain reaction. Cell cycle profiles were determined using a FACSCalibur Flow Cytometer. RESULTS: The cell cycle was arrested in the G0/G1 phase, and the percentage of cells in S phase decreased with senescence. CCND1, RB1, MMP1, and IL6 were upregulated in senescent fibroblasts. A similar upregulation was not observed in young cells. Incubation with γ-tocotrienol decreased CCND1 and RB1 expression in senescent fibroblasts, decreased cell populations in the G0/G1 phase and increased cell populations in the G2/M phase. γ-Tocotrienol treatment also upregulated ELN and COL1A1 and downregulated MMP1 and IL6 expression in young and senescent fibroblasts. CONCLUSION: γ-Tocotrienol prevented cellular aging in human diploid fibroblasts, which was indicated by the modulation of the cell cycle profile and senescence-associated gene expression.

[Studying the anti-aging effect of human growth hormone on human fibroblast cells via telomerase activity]

In recent years, studies have focused on the telomerase for cancer treatment by repressing telomerase in cancerous cells or prevent cell aging by activating it in the aged cells. Thus, in these studies natural and synthetic agents have been used to repress or activate telomerase. In this research, we investigated the effects of human growth hormone [hGH] on aging via evaluation of telomerase activity. Primary human foreskin fibroblast cells were isolated, cultured and treated with different concentrations of hGH. BrdU and MTT cell proliferation assays and cells number counting. Cell aging was assayed by the senescence sensitive galactosidase staining method. Telomerase activity was measured with a telomerase PCR ELISA kit.Data were analyzed with SPSS software [one-way ANOVA and univariate ANOVA]. Our results indicated that cells treated with a lower concentration [0.1, 1 ng/ml] of hGH had more green color cells [aged cells]. Furthermore, cell proliferation increased with increasing hGH concentrations [10 to 100 ng/ml] which was significant in comparison with untreated control cells. TRAP assay results indicated that telomerase activity increased with increasing hGH concentration, but there was no significant difference. Additionally, more rapid cell growth and telomerase activity was noted in the absence of H2 O2 when compared with the presence of H2 O2, which was significantly different. Although increasing cell proliferation along with increasing hGH concentration was confirmed by all cell proliferation assays, only the cell counting test was statistically significant. Thus, it is inconclusive that hGH [up to 100 ng/ml] has an anti-aging effect. Also, because there was no significant difference in the telomerase activity results [in spite of increasing progress along with increasing hGH concentration] we can not certainly conclude that hGH [up to 100 ng/ml] impacts telomerase activity

Involvement of mitogen-activated protein kinases and p21Waf1 in hydroxyurea-induced G1 arrest and senescence of McA-RH7777 rat hepatoma cell line

Hydroxyurea is commonly used to treat hematologic disorders and some type of solid tumors, but the mechanism for its therapeutic effect is not clearly known. In this study, we examined the effect of hydroxyurea on rat hepatoma McA-RH7777 cells, specifically, on the role of mitogen-activated protein (MAP) kinase signal transduction pathways and p21Waf1, p27Kip1 and p53. Rat hepatoma McA-RH7777 cells treated with hydroxyurea for 7 days, caused the inhibition of cell growth in a dose-dependent manner. But, this growth inhibition was not caused by necrosis or apoptosis but instead was associated with cell senescence-like change as evidenced by senescence associated-beta-galactosidase staining, and cells arrest at G1 phase of cell cycle. Phosphorylation of MAP kinases, such as ERK, JNK, and p38, was found to be decreased after treatment of cells with hydroxyurea. But, the expression of p21Waf1 was increased, while p27Kip1 and p53 were not detected in hydroxyurea treated rat hepatoma cells. Hydroxyurea treatment induced G1 arrest and a senescence-like changes in rat hepatoma McA-RH7777 cells may be the likely results of signal disruption of MAP kinases (ERK, JNK, and p38 MAP kinase) and p21Waf1 over-expression.

The effects of laminin on the characteristics and differentiation of neuronal cells from epidermal growth factor-responsive neuroepithelial cells

Many extracellular matrix molecules are expressed in the embryonic nervous system and there is some evidence that they are important regulators of neural development. Of these molecules, laminin appears to be the most potent, affecting virtually all neurons of the peripheral and central nervous system. This study was undertaken to investigate the effects of laminin on the proliferation and differentiation of cultured neuroepithelial cells taken from fetal rat forebrains (embryonic day 17-19). The results are summarized as follows. 1) Neuroepithelial cells cultivated in epidermal growth factors containing serum-free medium subsequently differentiated into neurons, astrocytes, and oligodendrocytes. 2) Neuronal cells derived from neuroepithelial cells were immunoreactive for gamma-aminobutyric acid (GABA) or substance P, but were not for serotonin and tyrosine hydroxylase. 3) In western blot analysis, the phosphorylated neurofilament content in neuronal cells was higher in culture on laminin than in culture on poly-L-lysine (PLL). 4) The proliferation rate of GABAergic neurons was higher in culture on laminin than in culture on PLL. These results suggest that GABAergic and substance P-ergic neurons can be differentiated from neuroepithelial cells and that laminin promotes the differentiation of neuronal cells from neuroepithelial cells and the increased proliferation rate of GABAergic cells.

Effect of vitamin A excess on germ cell development in prepubertal rat testis.

Vitamin A in graded doses of 125, 250 and 375 U.S.P./kg body wt, po, for 10 days (d 21-30) drastically reduced the testicular weight by 25 to 62% and seminiferous tubular diameter by 14 to 35% in prepubertal rats in lowest and highest doses of the treatment. The treatment induced disproportionate enlargement of nuclei and cytoplasm of the germ cells; predominantly the preleptotene and pachytene spermatocytes. These abnormal germ cells, often with 2 or 3 nuclei displayed vacuolated cytoplasm surrounding pyknotic or granulated or dispersed chromatin granules within the nuclei in a dose proportionate manner. The round spermatids were the most sensitive cell types which completely disappeared in two higher doses of treatment. Vacuolation of Sertoli cell cytoplasm in about 25% of the tubules with associated increase in intertubular space was also observed in rats treated with the highest dose of the vitamin. Circulatory levels of FSH, LH and testosterone remained unaltered following the vitamin excess treatment. Therefore, it is suggested that excess vitamin A even for shorter duration like the present one is detrimental to developing cell types and prevents the progress of the spermatogenic process beyond the round spermatid stage.