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Microplastics (MPs) accumulate in tissues, including kidney tissue, while Bisphenol A (BPA) is a plasticizer of particular concern. At present, the combined effects of MPs and BPA are unexplored in human renal cells. Therefore, we exposed a proximal tubular cell line (PTECs) to polyethylene (PE)-MPs and BPA, both separately and in combination. When co-exposed, cells showed a significantly reduced cell viability (MTT test) and a pronounced pro-oxidant (MDA levels, NRF2 and NOX4 expression by Western blot) and pro-inflammatory response (IL1β, CCL/CCR2 and CCL/CCR5 mRNAs by RT-PCR), compared to those treated with a single compound. In addition, heat shock protein (HSP90), a chaperone involved in multiple cellular functions, was reduced (by Western Blot and immunocytochemistry), while aryl hydrocarbon receptor (AHR) expression, a transcription factor which binds environmental ligands, was increased (RT-PCR and immunofluorescence). Our research can contribute to the study of the nephrotoxic effects of pollutants and MPs and shed new light on the combined effects of BPA and PE-MPs.

Abstract Identifying oncological applications for drugs that are already approved for other medical indications is considered a possible solution for the increasing costs of cancer treatment. Under the hypothesis that nutritional stress through fasting might enhance the antitumour properties of at least some non-oncological agents, by screening drug libraries, we find that cholesterol biosynthesis inhibitors (CBIs), including simvastatin, have increased activity against cancers of different histology under fasting conditions. We show fasting’s ability to increase CBIs’ antitumour effects to depend on the reduction in circulating insulin, insulin-like growth factor-1 and leptin, which blunts the expression of enzymes from the cholesterol biosynthesis pathway and enhances cholesterol efflux from cancer cells. Ultimately, low cholesterol levels through combined fasting and CBIs reduce AKT and STAT3 activity, oxidative phosphorylation and energy stores in the tumour. Our results support further studies of CBIs in combination with fasting-based dietary regimens in cancer treatment and highlight the value of fasting for drug repurposing in oncology.

There is a growing concern within the medical community about the potential burden of microplastics on human organs and tissues. In this study, we investigated by microRaman spectroscopy the presence of microplastics in human kidneys and urine. Moreover, an open-access software was developed and validated for the project, which enabled the comparison between the investigated spectra and a self-created spectral database, thus enhancing the ability to characterize polymers and pigments in biological matrices. Healthy portions of ten kidneys obtained from nephrectomies, as well as ten urine samples from healthy donors were analyzed: 26 particles in both kidney and urine samples were identified, with sizes ranging from 3 to 13 μm in urine and from 1 to 29 μm in kidneys. The most frequently determined polymers are polyethylene and polystyrene, while the most common pigments are hematite and Cu-phthalocyanine. This preclinical study proves the presence of microplastics in renal tissues and confirms their presence in urine, providing the first evidence of kidney microplastics deposition in humans.

Background: Chronic kidney disease (CKD) is a progressive systemic condition characterized by numerous complications. Among these, alterations in skeletal muscle physiology, such as sarcopenia, are particularly significant, as they are associated with poor outcomes and reduced quality of life. Summary: Various interventions, including pharmacological approaches and lifestyle modifications have been investigated to slow CKD progression and prevent or treat its complications. Physical exercise, in particular, has emerged as a promising intervention with multiple beneficial effects. These include improvements in physical functioning, increased muscle mass, modulation of metabolic abnormalities, and reduced cardiovascular risk. However, the pathophysiology of physical exercise in patients with kidney disease is complex and remains only partially understood. A crucial advancement in understanding this phenomenon has been the identification of myokines – molecules expressed and released by skeletal muscle in response to physical activity. These myokines can exert both paracrine and systemic effects, influencing not only skeletal muscle physiology but also other processes such as energy metabolism and lipid regulation. Key Messages: The interplay among skeletal muscle, physical activity, and myokines may act as a pivotal regulator in various physiological processes, including aging, as well as in pathological conditions like cachexia and sarcopenia, frequently observed in CKD patients at different stages, including patients on dialysis. Despite the potential importance of this relationship, only a limited number of studies have explored the relationship between exercise and myokine, and the effect of this interaction on experimental models or individuals with kidney disease. In the following sections, we review and discuss this topic.

Abstract Background An emerging hypothesis is that the activation of innate immunity in the muscle of patients with chronic kidney disease (CKD) is implicated in the development and progression of wasting and cachexia. We previously observed that Toll‐like receptor‐4 (TLR4) and its downward NF‐κB‐dependent pro‐inflammatory pathways are activated in CKD muscle. It is however unknown if TLR4 can activate the TLR4/NOD, LRR, and pyrin domain‐containing protein 3 (NLRP3) inflammasome pathway, which is implicated in cardiovascular disease and frailty, clinical settings that are commonly observed in CKD patients. Methods In a case–control cohort study, we hypothesized that a TLR4/NLRP3 inflammasome pathway is activated in skeletal muscle in uraemia. First, we studied the regulation TLR4/NLRP3/caspase‐1 in skeletal muscle biopsies (20M/11F) obtained from 31 non‐diabetic CKD5 patients (eGFR 8 ± 1 mL/min 1.73 m2) scheduled for peritoneal dialysis catheter insertion and 15 controls (10M/5F, eGFR 99 ± 6 mL/min 1.73 m2). Second, the effects of uraemic serum on the TLR4/NLRP3 inflammasome pathway were studied in C2C12 cells. Results In the muscle of CKD subjects, NLRP3 mRNA as well as its protein were overexpressed (by ~16‐fold, respectively, P

Conhecer a influência do background familiar na acumulação de capital humano é essencial para que se possa desenhar políticas públicas voltadas à elevação do nível de escolaridade da população. Este trabalho analisa a mobilidade intergeracional de educação no Brasil segundo a condição de migração. Verificam-se as mudanças no status educacional dos indivíduos que migraram na infância ou início da adolescência do Nordeste para o Sudeste entre as décadas de 1950 e 1980, tendo em vista a importância desse fluxo migratório na história recente do país. Os dados utilizados são provenientes da Pesquisa Nacional por Amostra de Domicílios (PNAD/IBGE) de 2014, que contou com um suplemento de mobilidade sócio-ocupacional. A metodologia do estudo compreende a estimação do grau de persistência intergeracional de educação, mediante um modelo de regressão linear, e o ajuste de um modelo logit ordenado para os níveis de escolaridade alcançados pelos indivíduos. Os resultados contrastam com os obtidos na maior parte da literatura internacional e mostram que o migrante na infância ou primeiros anos da adolescência NE-SE entre as décadas de 1950 e 1980 possuía menor mobilidade intergeracional de educação, quando comparado ao nativo tanto região de origem como de destino.

Abstract Sites and mechanisms regulating the supply of homocysteine (Hcy) to the circulation are unexplored in humans. We studied the exchange of Hcy across the forearm in CKD patients (n = 17, eGFR 20 ± 2 ml/min), in hemodialysis (HD)‐treated patients (n = 14) and controls (n = 9). Arterial Hcy was ~ 2.5 folds increased in CKD and HD patients (p

Plastic pollution became a main challenge for human beings as demonstrated by the increasing dispersion of plastic waste into the environment. Microplastics (MPs) have become ubiquitous and humans are exposed daily to inhalation or ingestion of plastic microparticles. Recent studies performed using mainly spectroscopy or spectrometry-based techniques have shown astounding evidence for the presence of MPs in human tissues, organs and fluids. The placenta, meconium, breast milk, lung, intestine, liver, heart and cardiovascular system, blood, urine and cerebrovascular liquid are afflicted by MPs’ presence and deposition. On the whole, obtained data underline a great heterogeneity among different tissue and organs of the polymers characterized and the microparticles’ dimension, even if most of them seem to be below 50–100 µm. Evidence for the possible contribution of MPs in human diseases is still limited and this field of study in medicine is in an initial state. However, increasing studies on their toxicity in vitro and in vivo suggest worrying effects on human cells mainly mediated by oxidative stress, inflammation and fibrosis. Nephrological studies are insufficient and evidence for the presence of MPs in human kidneys is still lacking, but the little evidence present in the literature has demonstrated histological and functional alteration of kidneys in animal models and cytotoxicity through apoptosis, autophagy, oxidative stress and inflammation in kidney cells. Overall, the manuscript we report in this review recommends urgent further study to analyze potential correlations between kidney disease and MPs’ exposure in human.

Protein energy wasting (PEW) is a common complication both in chronic kidney disease (CKD) and end-stage kidney disease (ESKD). Of note, PEW is one of the stronger predictors of morbidity and mortality in this patient population. The pathogenesis of PEW involves several mechanisms, including anorexia, insulin resistance, acidosis and low-grade inflammation. In addition, “sterile” muscle inflammation contributes to PEW at an advanced CKD stage. Both immune and resident muscle cells can activate innate immunity; thus, they have critical roles in triggering “sterile” tissue inflammation. Toll-like receptor 4 (TLR4) can detect endogenous danger-associated molecular patterns generated or retained in blood in uremia and induce a sterile muscle inflammatory response via NF-κB in myocytes. In addition, TLR4, though the activation of the NLRP3 inflammasome, links the sensing of metabolic uremic stress in muscle to the activation of pro-inflammatory cascades, which lead to the production of IL-1β and IL-18. Finally, uremia-induced accelerated cell senescence is associated with a secretory phenotype that favors fibrosis in muscle. Targeting these innate immune pathways could lead to novel therapies for CKD-related PEW.

Background and Aim: High lipoprotein(a) [Lp(a)] is a well-established cardiovascular (CV) risk factor, but the effect of mildly elevated Lp(a) on CV health is largely unknown. Our aim was to evaluate if Lp(a) is associated with the severity of carotid atherosclerosis (CA) in the specific subset of metabolic syndrome (MetS).Patients and Methods: Subjects with diagnosed MetS and ultrasound-assessed CA were enrolled. Those patients were categorized according to the severity of CA (moderate vs. severe), and the circulating levels of Lp(a) alongside with clinical, anthropometric, and biochemical data were collected.Results: Sixty-five patients were finally included: twenty-five with moderate and forty with severe CA (all with asymptomatic disease). Intergroup comparison showed Lp(a) as the only significantly different variable [6 (2–12) mg/dl vs. 11.5 (6–29.5) mg/dl; p = 0.018]. Circulating levels of Lp(a) were also confirmed as the only variable independently associated with severity of CA at logistic regression analysis [OR 2.9 (95% CI 1.1–7.8); p = 0.040]. ROC curve analysis for Lp(a) confirmed a serum level of 10 mg/dl as the best cut-off value [AUC 0.675 (95% CI 0.548–0.786)]. Although sensitivity and specificity were suboptimal (69.0 and 70.4%, respectively)—likely due to the small sample size—this result is in line with those previously reported in the literature.Conclusion: Lp(a) is independently associated with severity of CA in the subgroup of MetS patients.

Resumo Entre 2004 e 2014, o Brasil vivenciou forte expansão do consumo popular, graças ao aumento do poder aquisitivo das famílias de baixa renda. Este artigo analisa, pela ótica microeconômica, as modificações no padrão de consumo domiciliar resultantes desse cenário, buscando avaliar em que medida a crise instalada no país a partir de 2014 foi capaz de reverter a melhoria no nível de bem-estar alcançada no período precedente. Para tanto, são analisados os dados da Pesquisa de Orçamentos Familiares (POF/IBGE) de 2017-2018, comparando-os com os de sua edição anterior (2008-2009). São estimadas as despesas familiares per capita em diferentes categorias, bem como suas elasticidades e razões de concentração em relação à renda, averiguando-se quais tipos de gasto tornaram-se mais (ou menos) concentrados nos relativamente ricos. Especial atenção é conferida às despesas de consumo, tendo em vista sua influência direta no nível de bem-estar das famílias.

Arterial hypertension (AH) is a global challenge that greatly impacts cardiovascular morbidity and mortality worldwide. AH is a major risk factor for the development and progression of kidney disease. Several antihypertensive treatment options are already available to counteract the progression of kidney disease. Despite the implementation of the clinical use of renin–angiotensin aldosterone system (RAAS) inhibitors, gliflozins, endothelin receptor antagonists, and their combination, the kidney damage associated with AH is far from being resolved. Fortunately, recent studies on the molecular mechanisms of AH-induced kidney damage have identified novel potential therapeutic targets. Several pathophysiologic pathways have been shown to play a key role in AH-induced kidney damage, including inappropriate tissue activation of the RAAS and immunity system, leading to oxidative stress and inflammation. Moreover, the intracellular effects of increased uric acid and cell phenotype transition showed their link with changes in kidney structure in the early phase of AH. Emerging therapies targeting novel disease mechanisms could provide powerful approaches for hypertensive nephropathy management in the future. In this review, we would like to focus on the interactions of pathways linking the molecular consequences of AH to kidney damage, suggesting how old and new therapies could aim to protect the kidney.

IntroductionThe Forkhead box protein P3 (FOXP3) is a transcription factor central to the function of regulatory T cells (Treg). Mutations in the FOXP3 gene lead to a systemic disease called immune dysregulation, polyendocrinopathy, and enteropathy, an X-linked syndrome (IPEX) characterized by the triad of early-onset intractable diarrhea, type 1 diabetes, and eczema. An atypical presentation of IPEX has been reported.MethodWe report rare cases with equivocal clinical associations that included inflammatory, kidney, and hematologic involvements screened with massively parallel sequencing techniques.ResultsTwo patients with hemizygous mutations of FOXP3 [c.779T>A (p.L260Q)] and [c.1087A>G (p.I363V)] presented clinical manifestations not included in typical cases of IPEX: one was a 16-year-old male patient with an initial clinical diagnosis of autoimmune lymphoproliferative syndrome (ALPS) and who developed proteinuria and decreased kidney function due to membranous nephropathy, an autoimmune renal condition characterized by glomerular sub-epithelial antibodies. The second patient was a 2-year-old child with bone marrow failure who developed the same glomerular lesions of membranous nephropathy and received a bone marrow transplantation. High levels of IgG4 in serum, bone marrow, and kidney led to the definition of IgG4-related kidney disease (IgG4 RKD) in this young boy. The circulating Treg levels were normal in the former case and very low in the second.ConclusionTwo atypical associations of functional mutations of FOXP3 that include ALPS and IgG4 RKD are described. Membranous nephropathy leading to renal failure completed in both cases the clinical phenotypes that should be included in the clinical panorama of FOXP3 failure.

Resumo Este trabalho analisa o efeito do background familiar sobre os rendimentos do trabalho e sobre os retornos da escolaridade no Brasil, comparando os resultados obtidos por brancos e negros. São estimadas equações de rendimento com dados de 1996 e 2014 da Pesquisa Nacional por Amostra de Domicílios (Pnad/IBGE), adotando- -se a escolaridade dos pais do trabalhador como proxy de seu background familiar. Os resultados mostram que ter um diploma universitário tem efeito pronunciado sobre os rendimentos, porém em menor magnitude para os negros. Entre 1996 e 2014, apesar de ter ocorrido uma diminuição do efeito diploma, bem como do diferencial salarial entre brancos e negros, não houve redução da importância do background familiar para o desempenho dos indivíduos no mercado de trabalho.

Membranous nephropathy (MN) is one of the most common causes of adult-onset nephrotic syndrome. We describe the cases of 2 young women in their 20s presenting with nephrotic syndrome due to antiphospholipase A2 receptor (anti-PLA2R)–negative MN, that was found to be associated with benign tumors. Both women had no extrarenal symptoms of a connective tissue disease, infection, or malignancy. They both had been previously healthy and were not receiving treatment with any drugs. Both had MN on kidney biopsy. Biopsies were negative for PLA2R antigen, and their serum did not demonstrate the presence of anti-PLA2R antibodies. Both were investigated for a secondary cause on the basis of negative anti-PLA2R serology and biopsy features supportive of secondary MN and were found to have benign tumors on radioimaging: a uterine leiomyoma and mesenteric fibromatosis, respectively. In both instances, the nephrotic syndrome remitted following resection of the tumors. To our knowledge, uterine leiomyoma and mesenteric fibromatosis have not previously been described in association with MN. These cases highlight the importance of pursuing a secondary cause of MN in patients without anti-PLA2R antibodies in serum or PLA2R antigen on kidney biopsy.

The mechanisms by which hyperuricemia induces vascular dysfunction and contributes to cardiovascular disease are still debated. Phenotypic transition is a property of vascular smooth muscle cells (VSMCs) involved in organ damage. The aim of this study was to investigate the effects of uric acid (UA) on changes in the VSMC cytoskeleton, cell migration and the signals involved in these processes. MOVAS, a mouse VSMC line, was incubated with 6, 9 and 12 mg/dL of UA, angiotensin receptor blockers (ARBs), proteasome and MEK-inhibitors. Migration property was assessed in a micro-chemotaxis chamber and by phalloidin staining. Changes in cytoskeleton proteins (Smoothelin B (SMTB), alpha-Smooth Muscle Actin (αSMA), Smooth Muscle 22 Alpha (SM22α)), Atrogin-1 and MAPK activation were determined by Western blot, immunostaining and quantitative reverse transcription PCR. UA exposition modified SMT, αSMA and SM22α levels (p < 0.05) and significantly upregulated Atrogin-1 and MAPK activation. UA-treated VSMCs showed an increased migratory rate as compared to control cells (p < 0.001) and a re-arrangement of F-actin. Probenecid, proteasome inhibition and ARBs prevented the development of dysfunctional VSMC. This study shows, for the first time, that UA-induced cytoskeleton changes determine an increase in VSMC migratory rate, suggesting UA as a key player in vascular remodeling.

Abstract Background Muscle wasting from chronic kidney disease (CKD) or from defective insulin signalling results in morbidity and, ultimately, mortality. We have identified an endogenous mediator of insulin resistance, signal regulatory protein alpha (SIRPα), which leads to cachexia in mice and is associated with cachexia in patients with CKD. Methods We assessed insulin signalling and mechanisms causing muscle atrophy plus white adipose tissue (WAT) metabolism in mouse models of CKD or acute diabetes (streptozotocin treatment). We then examined these factors in mice with global knockout (KO) of SIRPα and sought mediators of metabolic responses in muscle and adipose tissues of mice with either muscle‐specific or adipose tissue‐specific KO of SIRPα. Metabolic responses were confirmed in primary cultures of adipose cells. Results In mice with CKD, SIRPα expression was increased in WAT (three‐fold, P < 0.05), and this was associated with precursors of cachexia: ‘pathologic browning', thermogenesis, and a two‐fold activation of protein kinase A (P < 0.05 vs. control mice) plus loss of adipose tissue mass. In contrast, mice with SIRPα global KO and CKD or acute diabetes experienced improved insulin signalling and activation of pAkt plus ‘physiologic browning' of WAT. These mice avoided losses of muscle and adipose tissues and experienced a 31% improvement in survival (P < 0.05) than did wild‐type mice with CKD. In muscle‐specific SIRPα KO mice with CKD, we uncovered that serum SIRPα levels (P < 0.05) were suppressed and were associated with improved insulin signalling both in skeletal muscles and in WAT. These changes were accompanied by physiologic WAT browning. However, in adipose‐specific SIRPα KO mice with CKD, levels of serum SIRPα were increased over two‐fold (P < 0.05), while muscle losses were minimally inhibited. Clinical implications of SIRPα signalling are suggested by our findings that include increased SIRPα expression in muscle and adipose tissues (P < 0.05 vs. healthy controls) plus higher SIRPα levels in the serum of patients with CKD (2.4‐fold, P=0.000017 vs. healthy controls). Conclusions Our results show that SIRPα plays an important role as an anti‐insulin mediator regulating pathways to cachexia. In muscle‐specific SIRPα KO, changes in SIRPα serum levels seem to improve insulin signalling in muscle and WAT, suggesting crosstalk between muscle and adipose tissue. Therefore, targeting SIRPα may prevent cachexia in patients with CKD or acute diabetes.

Resumo Este artigo analisa a segregação por sexo nos cursos presenciais de ensino superior brasileiro, investigando suas causas, características e evolução no tempo. Para tanto, são calculados indicadores sintéticos de segregação com base nas edições de 2000 e 2017 do Censo da Educação Superior. Nesse período, a queda no grau geral de segregação foi tímida e resultou de dois movimentos opostos: a redução da estratificação de homens e mulheres entre as grandes áreas de conhecimento, contrabalançada pelo aumento da segregação dentro delas. Assim, ao nível mais agregado de análise, há tendência à integração por sexo dos campos de estudo. Porém, em se tratando de carreiras específicas, persistem os estereótipos de gênero, com segmentação entre cursos tipicamente masculinos e femininos.

A current hypothesis is that dialysis-treated patients are “anabolic resistant” i. e., their muscle protein synthesis (MPS) response to anabolic stimuli is blunted, an effect which leads to muscle wasting and poor physical performance in aging and in several chronic diseases. The importance of maintaining muscle mass and MPS is often neglected in dialysis-treated patients; better than to describe mechanisms leading to energy-protein wasting, the aim of this narrative review is to suggest possible strategies to overcome anabolic resistance in this patient's category. Food intake, in particular dietary protein, and physical activity, are the two major anabolic stimuli. Unfortunately, dialysis patients are often aged and have a sedentary behavior, all conditions which per se may induce a state of “anabolic resistance.” In addition, patients on dialysis are exposed to amino acid or protein deprivation during the dialysis sessions. Unfortunately, the optimal amount and formula of protein/amino acid composition in supplements to maximixe MPS is still unknown in dialysis patients. In young healthy subjects, 20 g whey protein maximally stimulate MPS. However, recent observations suggest that dialysis patients need greater amounts of proteins than healthy subjects to maximally stimulate MPS. Since unneccesary amounts of amino acids could stimulate ureagenesis, toxins and acid production, it is urgent to obtain information on the optimal dose of proteins or amino acids/ketoacids to maximize MPS in this patients' population. In the meantime, the issue of maintaining muscle mass and function in dialysis-treated CKD patients needs not to be overlooked by the kidney community.

Background: Chronic kidney disease (CKD) reduces both Klotho expression and its shedding into circulation, an effect that accelerates progression and cardiovascular complications. However, the mechanisms that regulate Klotho release by the human kidney are still unknown. Methods: We measured plasma Klotho across the kidney, splanchnic organs and lung in 22 patients (71 ± 2 years, estimated glomerular filtration rate [eGFR] 60 ± 5.4 mL/min 1.73 m2) during elective diagnostic cardiac catheterizations. Results: Although the Klotho average renal vein concentrations were remarkably higher (by ∼9%) than arterial values, the kidney removed Klotho (or was at zero balance) in 7 subjects, indicating that the kidney contribution to systemic Klotho is not constant. Klotho fractional enrichment across the kidney was inversely related to plasma sodium (r = 0.43, p = 0.045) and acid uric acid levels (r = 0.38, p = 0.084) and directly, to renal oxygen extraction (r = 0.56, p = 0.006). In multivariate analysis, renal oxygen extraction was the only predictor of the enrichment of Klotho across the kidney, suggesting the dependence of renal Klotho release on tubular hypoxia or oxidative metabolism. Klotho balance was neutral across the lung. In patients with eGFR

Resumo Este artigo analisa a evolução da segregação ocupacional por sexo no mercado de trabalho brasileiro de 2004 a 2015. Além da mensuração da segregação por meio de indicadores tradicionais, como o índice de dissimilaridade e o de Gini, utiliza-se a classe de medidas aditivamente decomponíveis proposta por Hutchens (2004), que permite decompor a segregação em duas parcelas: uma relacionada à segregação entre grandes grupos ocupacionais; e outra que corresponde a uma soma ponderada dos níveis de segregação dentro desses grupamentos. Os resultados mostram que a segregação aumentou entre 2004 e 2015, revertendo a tendência de queda que vinha sendo relatada na literatura referente a anos anteriores a esse período. A análise de decomposição indica que tal crescimento foi impulsionado pela segregação entre os grandes grupos ocupacionais, portanto, entre grupos com ocupações mais heterogêneas entre si. Conclui-se que, à medida que o nível da participação feminina no mercado de trabalho se estabiliza, o processo de integração das ocupações segundo o sexo também apresenta seus primeiros sinais de esgotamento.

Este trabalho analisa os fatores que influenciam a decisão dos empregados em serviços no Brasil, ante a possibilidade de trabalhar no setor privado, no setor público federal, na esfera estadual ou na municipal. Além de testar o papel de um conjunto de atributos pessoais e socioeconômicos na determinação do setor de emprego, examina-se o efeito de variáveis relativas ao background familiar na alocação setorial. Os resultados mostram um efeito intergeracional, com maior probabilidade de emprego no setor público caso o pai tenha sido servidor. Esse efeito, no entanto, tem maior expressão nas esferas estadual e municipal de governo e perdeu importância, ao se compararem os dados de 1996 e de 2014.

Introduction: Early studies have shown that patients with chronic kidney disease (CKD) are able to maintain nitrogen balance despite significantly lower protein intake, but how and to what extent muscle protein metabolism adapts to a low-protein diet (LPD) or to a supplemented very LPD (sVLPD) is still unexplored. Methods: We studied muscle protein turnover by the forearm perfusion method associated with the kinetics of 2H-phenylalanine in patients with CKD: (i) in a parallel study in subjects randomized to usual diet (1.1 g protein/kg, n = 5) or LPD (0.55 g protein/kg, n = 6) (Protocol 1); (ii) in a crossover, self-controlled study in subjects on a 0.55 g/kg LPD followed by a sVLPD (0.45 g/kg + amino/ketoacids 0.1 g/kg, n = 6) (Protocol 2). Results: As compared with a 1.1 g/kg containing diet, a 0.55 g/kg LPD induced the following: (i) a 17% to 40% decrease in muscle protein degradation and net protein balance, respectively, (ii) no change in muscle protein synthesis, (iii) a slight (by approximately 7%, P < 0.06) decrease in whole-body protein degradation, and (iv) an increase in the efficiency of muscle protein turnover. As compared with an LPD, an sVLPD induced the following: (i) no change in muscle protein degradation, and (ii) an approximately 50% decrease in the negative net protein balance, and an increase in the efficiency of muscle protein turnover. Conclusion: The results of these studies indicate that in patients with CKD the adaptation of muscle protein metabolism to restrained protein intake can be obtained via combined responses of protein degradation and the efficiency of recycling of amino acids deriving from protein breakdown. Keywords: amino acids, chronic kidney disease, ketoacids, low-protein diet, nutrition

During visceral interventions, the transient clampage of supraceliac aorta causes ischemia/reperfusion (I/R) in kidneys, sometime resulting in acute renal failure; preclinical studies identified redox imbalance as the main driver of I/R injury. However, in humans, the metabolic/inflammatory responses seem to prevail on oxidative stress. We investigated myostatin (Mstn) and proprotein convertase subtilisin/kexin type 9 (PCSK9), proatherogenic mediators, during renal I/R. Compared to sham-operated animals, the kidneys of rats who had experienced ischemia (30 min) had higher Mstn and PCSK9 expression after 4 h of reperfusion. After 24 h, they displayed tubular necrosis, increased nitrotyrosine positivity, and nuclear peroxisome proliferator-activated receptor gamma coactivator-1alpha relocation, markers of oxidative stress and mitochondria imbalance. Mstn immunopositivity was increased in tubuli, while PCSK9 immunosignal was depleted; systemically, PCSK9 was higher in plasma from I/R rats. In HK-2 cells, both ischemia and reperfusion enhanced reactive oxygen species production and mitochondrial dysfunction. H2O2 upregulated Mstn and PCSK9 mRNA after 1 and 3.5 h, respectively. Accordingly, ischemia early induced Mstn and PCSK9 mRNA; during reperfusion Mstn was augmented and PCSK9 decreased. Mstn treatment early increased PCSK9 expression (within 8 h), to diminish over time; finally, Mstn silencing restrained ischemia-induced PCSK9. Our study demonstrates that renal I/R enhances Mstn and PCSK9 expression and that Mstn induces PCSK9, suggesting them as therapeutic targets for vascular protection during visceral surgery.

A current hypothesis is that transforming growth factor-β signaling ligands, such as activin-A and myostatin, play a role in vascular damage in atherosclerosis and chronic kidney disease (CKD). Myostatin and activin-A bind with different affinity the activin receptors (type I or II), activating distinct intracellular signaling pathways and finally leading to modulation of gene expression. Myostatin and activin-A are expressed by different cell types and tissues, including muscle, kidney, reproductive system, immune cells, heart, and vessels, where they exert pleiotropic effects. In arterial vessels, experimental evidence indicates that myostatin may mostly promote vascular inflammation and premature aging, while activin-A is involved in the pathogenesis of vascular calcification and CKD-related mineral bone disorders. In this review, we discuss novel insights into the biology and physiology of the role played by myostatin and activin in the vascular wall, focusing on the experimental and clinical data, which suggest the involvement of these molecules in vascular remodeling and calcification processes. Moreover, we describe the strategies that have been used to modulate the activin downward signal. Understanding the role of myostatin/activin signaling in vascular disease and bone metabolism may provide novel therapeutic opportunities to improve the treatment of conditions still associated with high morbidity and mortality.

This article examines the influence of macroeconomic factors in the capital structure of subsidiaries of foreign multinational companies (SFM) in Brazil by comparing them with local Brazilian companies (LBC) during the period from 1998–2008. Panel data econometrics was used to analyze the data and test the hypotheses. During this period, exchange rate variation was positively associated with local leverage, which supported the hypothesis of income hedging in the context of foreign currency exposure of the head office. We also found less local leverage for foreign multinational companies when the macroeconomics scenario became more stable. Finally, contrary to the initial hypothesis, differences in financing rates between Brazil and the SFMs’ head office country were positively related to local leverage.

Growing evidence suggests the involvement of TLR4, a receptor in the innate immune system, in muscle loss in uremia. Recently, we have evaluated TLR4 in human skeletal muscle from chronic kidney disease patients, by immunohistochemistry and image analysis. Unlike the commonly-used Western blot method, immunohistochemistry allows for the observation of protein distribution in the intact tissue while, image analysis, its quantification. In fact, our data highlighted our hypothesis that an enhanced TLR4 skeletal muscle cell expression contributes to the activation of the downward inflammatory pathway in uremic sarcopenia. In this protocol, we describe the procedure for immunostaining TLR4 in human skeletal muscle and for quantifying it by image analysis.

A low protein diet (LPD) has historically been used to delay uremic symptoms and decrease nitrogen (N)-derived catabolic products in patients with chronic kidney disease (CKD). In recent years it has become evident that nutritional intervention is a necessary approach to prevent wasting and reduce CKD complications and disease progression. While a 0.6 g/kg, high biological value protein-based LPD has been used for years, recent observational studies suggest that plant-derived LPDs are a better approach to nutritional treatment of CKD. However, plant proteins are less anabolic than animal proteins and amino acids contained in plant proteins may be in part oxidized; thus, they may not completely be used for protein synthesis. In this review, we evaluate the role of LPDs and plant-based LPDs on maintaining skeletal muscle mass in patients with CKD and examine different nutritional approaches for improving the anabolic properties of plant proteins when used in protein-restricted diets.

Thrombolysis is the gold standard treatment for acute ischemic stroke. Besides its fibrinolytic role, recombinant tissue plasminogen activator (r-tPA) holds several non-fibrinolytic functions. Here, we investigated the potential role of r-tPA on human primary neutrophil migration in vitro. By means of modified Boyden chamber migration assay and checkerboard analysis we showed a dose-dependent chemotactic effect of r-TPA with a maximum effect reached by 0.03 mg/mL (0.003–1 mg/mL). Pre-incubation with MAP kinases inhibitors allowed the identification of PI3K/Akt, but not ERK1/2 as the intracellular pathway mediating the observed effects. Furthermore, by means of real-time PCR, immunocytochemistry and cytofluorimetry we demonstrated that the r-tPA receptor low density lipoprotein receptor-related protein 1 (LRP-1) is synthetized and expressed by neutrophils in response to r-tPA and TNF-α. Inhibition of LRP-1 by receptor-associated protein (RAP), prevented r-tPA-mediated F-actin polymerization, migration and signal through Akt but not ERK1/2. Lastly, also neutrophil degranulation in response to r-tPA seems to be mediated by LRP-1 under adhesion conditions. In conclusion, we show that r-tPA induces neutrophil chemotaxis through LRP-1/Akt pathway. Blunting r-tPA-mediated neutrophil activation might be beneficial as an adjuvant therapy to thrombolysis in this setting.

No Brasil, as mulheres ainda são raras nos altos postos de comando das organizações. A percepção desta situação por parte dos dirigentes, no entanto, nem sempre é clara. No serviço público, em particular, a atitude menos discriminatória nas contratações - já que o acesso ao emprego público depende, via de regra, de aprovação prévia em concurso -, e a garantia de igualdade de tratamento a integrantes de uma mesma carreira conduzem à impressão de que o teto de vidro seja menos pronunciado. Este artigo reúne evidências de que, a despeito de seu modo de recrutamento por concurso, as carreiras do setor público brasileiro tampouco escapam ao teto de vidro. A distribuição desigual das mulheres nas distintas instâncias hierárquicas das organizações públicas se faz notar tanto em âmbito administrativo quanto técnico. As práticas discriminatórias sozinhas não explicam o fenômeno, cujas raízes também devem ser buscadas nas intersecções entre vida doméstica e profissional.

OBJECTIVE:The uremic toxin Indoxyl-3-sulphate (IS), a ligand of Aryl hydrocarbon Receptor (AhR), raises in blood during early renal dysfunction as a consequence of tubular damage, which may be present even when eGFR is normal or only moderately reduced, and promotes cardiovascular damage and monocyte-macrophage activation. We previously found that patients with abdominal aortic aneurysms (AAAs) have higher CD14+CD16+ monocyte frequency and prevalence of moderate chronic kidney disease (CKD) than age-matched control subjects. Here we aimed to evaluate the IS levels in plasma from AAA patients and to investigate in vitro the effects of IS concentrations corresponding to mild-to-moderate CKD on monocyte polarization and macrophage differentiation. METHODS:Free IS plasma levels, monocyte subsets and laboratory parameters were evaluated on blood from AAA patients and eGFR-matched controls. THP-1 monocytes, treated with IS 1, 10, 20 μM were evaluated for CD163 expression, AhR signaling and then induced to differentiate into macrophages by PMA. Their phenotype was evaluated both at the stage of semi-differentiated and fully differentiated macrophages. AAA and control sera were similarly used to treat THP-1 monocytes and the resulting macrophage phenotype was analyzed. RESULTS:IS plasma concentration correlated positively with CD14+CD16+ monocytes and was increased in AAA patients. In THP-1 cells, IS promoted CD163 expression and transition to macrophages with hallmarks of classical (IL-6, CCL2, COX2) and alternative phenotype (IL-10, PPARγ, TGF-β, TIMP-1), via AhR/Nrf2 activation. Analogously, AAA sera induced differentiation of macrophages with enhanced IL-6, MCP1, TGF-β, PPARγ and TIMP-1 expression. CONCLUSION:IS skews monocyte differentiation toward low-inflammatory, profibrotic macrophages and may contribute to sustain chronic inflammation and maladaptive vascular remodeling.

Utilizando dados da PNAD, o trabalho investiga o comportamento do hiato de rendimentos entre funcionários públicos e empregados do setor privado com carteira assinada, ocupados no setor terciário, de 1992 a 2005. São ajustadas, em separado, equações de rendimento, a fim de apontar as diferenças no efeito de vários fatores (idade, sexo, escolaridade, etc.) sobre o salário de cada categoria. Mediante o emprego da metodologia de Blinder-Oaxaca identifica-se quanto do diferencial de rendimentos entre os dois grupos se deve a diferenças na capacitação individual dos trabalhadores e quanto está associado a outros fatores, analisando como essa decomposição evoluiu ao longo do período 1992-2005. Um resultado importante é o crescimento do hiato de rendimentos entre os dois grupos, especialmente da parcela não explicada pelas diferenças na capacitação dos empregados.ABSTRACT Using data from an annual household survey (PNAD), this study analyses the behavior of the wage gap between public and private formal workers from the tertiary sector in Brazil from 1992 to 2005. Earnings equations are estimated separately for these two groups. Such equations allow us to evaluate the effect of age, gender, schooling, color (race), position in the occupation, weekly working time and other factors on earnings of each category. Blinder-Oaxaca methodology reveals how much of the wage gap between the workers of both sectors is due to differences in productive endowments and how much is due to other factors, such as the existence of segmentation between the public and the private labor market in Brazil. An important result is the increase of the wage gap between the two groups of workers, mainly of the part that can not be explained by workers' productive endowments.

Mild hyperuricemia has been linked to the development and progression of tubulointerstitial renal damage. However the mechanisms by which uric acid may cause these effects are poorly explored. We investigated the effect of uric acid on apoptosis and the underlying mechanisms in a human proximal tubule cell line (HK-2). Increased uric acid concentration decreased tubule cell viability and increased apoptotic cells in a dose dependent manner (up to a 7-fold increase, p