El riñón del niño prematuro: riesgos a largo plazo / The kidney of the premature child: long-term risks

Resumen: El recién nacido prematuro se enfrenta a las condiciones extrauterinas con sistemas aún inmaduros, tanto anatómica como fisiológicamente. El riñón termina de desarrollarse a finales del tercer trimes tre del embarazo, por lo que está especialmente expuesto a alterar su desarrollo normal en caso de nacer en forma prematura. Esta situación puede condicionar, entre otras consecuencias, una menor masa renal funcional y cambios microvasculares que representan un riesgo elevado de hipertensión arterial y daño renal crónico en el largo plazo. En el presente artículo se analiza la evidencia existente actual sobre estos riesgos en los prematuros y se ofrece un esquema de seguimiento de estos niños desde el punto de vista nefrológico.

Abstract: The premature newborn faces extrauterine conditions with some systems still immature, both ana tomically and physiologically. The kidney finishes developing at the end of the third trimester of pregnancy, so it is especially exposed to alter its normal development if preterm birth occurs. This si tuation may condition, among other consequences, a lower functional renal mass and microvascular changes comprising a high risk of chronic kidney disease in the long term and arterial hypertension. This article analyzes the current evidence on these risks in premature infants and offers a nephrology follow-up scheme of these children.

Evaluation of the cytotoxic and genotoxic effects by melamine and cyanuric acid co-exposure in human embryonic kidney 293 cells

The melamine and cyanuric acid (CA) complex has been suggested to cause the toxic effects observed in melamine-contaminated food or milk. However, the cytotoxic and genotoxic effects of co-exposure to melamine and CA are not fully clear. Therefore, the cytotoxic effects of melamine and CA were first examined by co‐exposure in human kidney 293 cells using the MTT assay. During a 24-h period for the three concentrations tested (0.5, 1, and 5 mg/mL), neither melamine nor CA alone showed significant toxic effects on 293 cells at 0.5 mg/mL, while higher concentrations led to decreased in cell viability. However, co-exposure to several combinations of melamine and CA [100:1, 10:1, 1:10, and 1:100 (v:v), at a final concentration of 0.5 mg/mL] did cause cytotoxicity with higher levels of CA leading to higher cytotoxicity. By contrast, while neither melamine nor CA alone induced phosphorylated-H2AX (γH2AX) foci formation, melamine and CA at a 100:1 ratio induced γH2AX foci 24 h post-treatment. The alkaline comet assay also revealed the presence of DNA damage following melamine and CA co-exposure. In vivo assay also revealed the presence of melamine-CA complex in the kidney. These data indicated that the cytotoxic and genotoxic effects of melamine and CA co-exposure differ from those of melamine or CA alone.

Study of the renal parenchymal volume during the human fetal period

ABSTRACT Objective: To evaluate the renal parenchymal area in human fetuses, providing a descriptive analysis on the renal area development by demographic factors during the second gestational trimester. Material and Methods: We analyzed 84 fetuses (44 males and 40 females), for a total of 168 renal units evaluated in terms of longitudinal length, superior pole width, inferior pole width and thickness. Renal volume was calculated by ellipsoid formula. After renal pelvis dissection, length and width were evaluated; as pelvis is free of urine, we considered thickness as 1mm. Renal pelvis volume was also calculated by ellipsoid formula. Renal parenchymal area was assessed by excluding the volume of the renal pelvis from the total renal volume. We performed the statistical analysis by simple linear regression assessing the association between the variables analyzed with the fetal age. Results: Gestational age ranged from 12 to 23 weeks post conception. Mean renal parenchymal area of the right kidney was 666.22mm3 (45.86 to 2375.35mm3) and for the left kidney was 606.76mm3 (68.63 to 2402.57mm3). No statistical difference was observed between the sides (p-value = 0.3456) or genders (p-value = 0.07429). Linear regression between renal parenchymal volume and gestational age was positive for right kidney (y = 133.74x-1479.94 / r2 = 0.4009) and left kidney (y = 149.53x-1761.59 / r2 = 0.4591). Conclusions: The linear regression analysis indicated that renal parenchymal area correlated significantly and positively with fetal age, weight and crown-rump length with no statistical differences between gender or laterality. These growth curves provide a reference for functional volume of the kidney during fetal period.

Uromodulin: a new biomarker of fetal renal function? / Uromodulina: um novo biomarcador de função renal fetal?

Abstract Introduction: Obstructive uropathies are main diseases affecting the fetus. Early diagnosis allows to establish the appropriate therapy to minimize the risk of damage to kidney function at birth. Biochemical markers have been used to predict the prognosis of renal function in fetuses. Uromodulin, also known by Tamm-Horsfall protein (THP) is exclusively produced in the kidneys and in normal conditions is the protein excreted in larger amounts in human urine. It plays important roles in kidneys and urinary tract. Also it participates in ion transport processes, interact with various components of the immune system and has a role in defense against urinary tract infections. Moreover, this protein was proved to be a good marker of renal function in adult patients with several renal diseases. Objective: To evaluate if uromodulin is produced and eliminated by the kidneys during fetal life by analyzing fetal urine and amniotic fluid and to establish correlation with biochemical parameter of renal function already used in Fetal Medicine Center at the Clinic Hospital of UFMG (CEMEFE/HC). Methods: Between 2013 and 2015, were selected 29 fetuses with indication of invasive tests for fetal diagnosis in monitoring at the CEMEFE/HC. Results: The determination of uromodulin was possible and measurable in all samples and showed statistically significant correlation with the osmolarity. Conclusion: There was a tendency of lower levels of Uromodulin values in fetuses with severe renal impairment prenatally. Thus, high levels of this protein in fetal amniotic fluid or fetal urine dosages possibly mean kidney function preserved.

Resumo Introdução: Uropatias obstrutivas estão entre as principais doenças que acometem o feto. O diagnóstico precoce destas doenças permite estabelecer a terapêutica adequada, visando minimizar os riscos de danos à função renal no nascimento. Os marcadores bioquímicos têm sido utilizados na predição do prognóstico da função renal em fetos. A uromodulina, também chamada de proteína de Tamm-Horsfall (THP), é produzida exclusivamente nos rins, e em condições normais, é a proteína excretada em maior volume na urina humana. Ela desempenha importantes funções nos rins e trato urinário. Participa dos processos de transporte de íons, interage com vários componentes do sistema imunológico e possui papel na defesa contra infecções do trato urinário. Além disso, se mostrou um bom biomarcador de função renal em adultos portadores de diversas doenças renais. Objetivos: Avaliar se a uromodulina é produzida e eliminada pelos rins durante a vida fetal através da análise de urina fetal e líquido amniótico, além de estabelecer correlação com o parâmetro bioquímico de função renal já utilizado no Centro de Medicina Fetal do Hospital das Clínicas da UFMG (CEMEFE/HC). Métodos: Entre 2013 e 2015, foram selecionados 29 fetos com indicação de exames invasivos para diagnóstico fetal em acompanhamento no CEMEFE/HC. Resultados: A dosagem da uromodulina foi possível e quantificável em todas as amostras e mostrou correlação significativa com a osmolaridade. Conclusão: A uromodulina mostrou uma tendência em apresentar valores reduzidos em fetos com grave comprometimento renal no pré-natal. Assim, valores elevados desta proteína em dosagens de urina fetal ou líquido amniótico podem significar uma função renal preservada.

Is there a trans-abdominal testicular descent during the second gestational trimester? Study in human fetuses between 13 and 23 weeks post conception

ABSTRACT Objectives To confirm if a real inner descend of testis occurs, correlating the testicular position with fetal parameters and analyzing the position of the testes relative to the internal ring. Material and Methods Twenty nine human fetuses between 13 and 23 weeks post conception (WPC) were studied. The fetuses were carefully dissected with the aid of a stereoscopic lens with 16/25X magnification and testicular position observed. With the aid of a digital pachymeter the distance between the lower pole of the kidney and the upper extremity of the testis (DK-T) was measured to show the position of the testis. During the dissection we also indicated the position of the testes relative to the internal ring. Means were statistically compared using simple linear regression and the paired T-test. Results The 58 testes had abdominal position. The DK-T in the right side measured between 0.17 and 1.82cm (mean=0.79cm) and in the left side it was between 0.12 and 1.84cm (mean=0.87cm), without statistically differences (p=0.0557). The linear regression analysis indicated that DK-T in both sides correlated significantly and positively with fetal age. All fetuses with more than 20 WPC, heavier than 350g and with CRL over 22cm had a greater distance than the average DK-T. We xobserved that the 58 testis remains adjacent to the internal ring throughout the period studied. Conclusions The testes remains adjacent to the internal ring throughout the period studied, indicating that there is no real trans-abdominal testicular descent during the second gestational trimester.

Does hyperglycemia in pregnancy change fetal kidney growth?: a longitudinal prospective study / A hiperglicemia na gravidez altera o crescimento renal fetal?: um estudo prospectivo longitudinal

PURPOSE: To measure fetal renal volume in normoglycemic and hyperglycemic pregnancies. METHODS: A longitudinal prospective study was conducted and included 92 hyperglycemic and 339 normoglycemic pregnant women attended at the prenatal service of a hospital from Rio de Janeiro State. Ultrasound examinations were performed to estimate gestational age at baseline and the kidney volume was estimated using the prolate ellipsoid volume equation. RESULTS: Fetal kidney volume growth between normoglycemic and hyperglycemic pregnancies are significantly different. The fetal kidney volume growth in pregnancy is positively correlated with gestational age explained by these predictor equations, by group: normal renal volume = exp (6.186+0.09×gestational week); hyperglycemic renal volume = exp (6.978+0.071×gestational week) and an excessive growth pattern for hyperglycemic pregnancies may be established according to gestational age. CONCLUSION: This is important for early detection of abnormalities in pregnancy, particularly in diabetic mothers.

OBJETIVO: O estudo foi desenvolvido para medir o volume renal fetal em gestações normoglicêmicas e hiperglicêmicas. MÉTODOS: Estudo prospectivo longitudinal, incluindo 92 gestantes hiperglicêmicas e 339 normoglicêmicas que procuraram o serviço pré-natal de um hospital no estado do Rio de Janeiro. A ultrassonografia foi realizada para estimar idade gestacional e volume renal foi estimado utilizando a equação de volume elipsoide. RESULTADOS: O crescimento fetal e os volumes renais entre gestações normoglicêmicas e hiperglicêmicas são estatisticamente distintos. O aumento do volume renal fetal na gravidez é correlacionada com a idade gestacional, de acordo com as seguintes equações preditores, por grupo: volume renal normal = exp (6,186+0,09×semana de gestação); e volume renal hiperglicêmico = exp (6,978+0,071×semana de gestação). CONCLUSÃO: Estes dados são importantes para detecção precoce de anormalidades na gravidez, principalmente em mães diabéticas.

[One-year follow-up of radiologic and clinical findings in children with prenatal and neonatal hydronephrosis]

Hydronephrosis is a common problem in prenatal and newborn infants diagnosed by ultrasonography. Bladder to ureter reflux, the upper or lower urinary tract obstruction, and neurogenic bladder are the most common causes of hydronephrosis in newborns and infants. In this study, 100 neonates and infants with hydronephrosis were observed clinically and laboratorically for one year. Patients were allocated to two groups of fetal and newborn infants by the time of detection of hydronephrosis. Classification of the severity of hydronephrosis was based on the anteriorposterior diameter of renal pelvis including: mild hydronephrosis [5-9 mm], moderate [10-15 mm], and severe [more than 15 mm]. Fifty four patients were boy and 46 were girl. Mean age of patients in first visit of fetal and newborn infants hydronephrosis were respectively 2.5 [79% asymptomatic] and 5 month [100% symptomatic]. Causes of fetal hydronephrosis were: bladder to ureter reflux [45%], idiopathic hydronephrosis [41%], ureteropelvic junction obstruction [UPJO] [3.11%], physiological hydronephrosis [7.5%], and posterior urethral valve [8.3%]. Bladder to ureter reflux was the most common cause of hydronephrosis in all of the patients [57%]. The most common causes of mild and severe hydronephrosis were bladder to ureter reflux and ureteropelvic junction obstruction, respectively. In patients with fetal hydronephrosis, 100%, 30% and 6% of cases of severe, moderate, and mild hydronephrosis need surgery, respectively. Using ultrasonography in pregnancy led to the discovery of most asymptomatic fetal hydronephrosis more than infant hydronephrosis

Modelo experimental para restrição do crescimento fetal em ratos: efeito sobre o glicogênio hepático e morfometria intestinal e renal / Experimental rat model for fetal growth restriction: effects on liver glycogen and intestinal and renal morphometry

OBJETIVO: avaliar a eficácia do modelo de RCIU por ligadura da artéria uterina simulando insuficiência placentária em ratos. MÉTODOS: fetos de ratas prenhes Sprague-Dawley foram divididos em três grupos: RCIU (restrição de crescimento intrauterino), com fetos submetidos à ligadura da artéria uterina com 18,5 dias de gestação (termo = 22 dias), C-RCIU (controle da restrição), com fetos do corno contralateral à ligadura, CE (Controle Externo), com fetos de ratas sem manipulação. Com 21,5 dias de gestação, foi realizada cesárea, os fetos foram pesados e dissecados para análise morfométrica e histológica do fígado, intestino e rins. RESULTADOS: os dados morfométricos avaliados mostraram o peso corpóreo (PC), hepático (PH) e intestinal (PI) dos fetos com RCIU menor que C-RCIU e CE (p<0,001). O peso placentário (PP), renal (PR) e as relações PH/PC, PI/PC e PR/PC não se alteraram. A espessura renal foi menor nos fetos com RCIU (p<0,001) e houve diminuição da camada mucosa e submucosa intestinal (p<0,05). A avaliação histológica mostrou diminuição do glicogênio hepático nos fetos com RCIU em relação aos grupos C-RCIU e CE. CONCLUSÕES: o modelo descrito foi eficiente e causou RCIU fetal simétrica com diminuição da maioria dos órgãos, especialmente do peso hepático, e alteração nos depósitos de glicogênio.

PURPOSE: to evaluate the effectiveness of the IUGR model by uterine artery ligation mimicking placental insufficiency in rats. METHODS: sprague-Dawley rat fetuses were divided into three groups: IUGR (intrauterine growth restriction), with fetuses in the right horn of pregnant rats subjected to right uterine artery ligation at 18.5 days of gestation (term = 22 days); C-IUGR (control of restriction), with control fetuses in the left horn, and EC (external control), with fetuses of intact rats. Animals were harvested by cesarean section at day 21.5 days of gestation. Fetuses were weighed and then sacrificed. The intestine, liver, kidney and placenta were weighed and dissected for morphometric and histological analysis. RESULTS: the morphometric data showed decreased body weight (BW), liver weight (LW) and intestinal weight (IW) of fetuses with IUGR compared to C-IUGR and EC (p<0.001). The placental weight (PW), renal weight (RW) and LW/BW, IW/BW, and RW/BW ratios did not change. IUGR fetuses had decreased kidney thickness (p<0.001) and decreased thickness of the intestinal mucosa and submucosa (p<0.05). Histological evaluation showed reduction of liver glycogen storage in fetuses with IUGR compared to C-IUGR and CE. CONCLUSIONS: the model described was efficient and caused symmetric fetal IUGR with decreased size of most organs, especially the liver, and changes in glycogen stores.

Anatomical study of the horseshoe kidney / Estudio anatómico del riñón en herradura

We present the anatomical study of a horseshoe kidney found during dissection practice at the human anatomy laboratory. The specimen consisted of a renal mass joined at its lower poles by an isthmus composed of renal parenchyma. We provide a macroscopic description of renal blood supply and the excretory system. We also discuss the anatomic and embryologic importance of this anomaly.

Se presenta el estudio anatómico de un riñón en herradura encontrado durante la práctica de disección en el Laboratorio de Anatomía Humana. La muestra consistió de una masa renal unida a sus polos inferiores por medio de un istmo de parénquima renal. Proporcionamos una descripción macroscópica de suministro sanguíneo renal y el sistema excretor. Asimismo, se discute la importancia anatómica y embriológica de esta anomalía.

Roles of mitogen-activated protein kinases and angiotensin II in renal development

Experimental and clinical evidence suggests that angiotensin II (AII) participates in renal development. Renal AII content is several-fold higher in newborn rats and mice than in adult animals. AII receptors are also expressed in higher amounts in the kidneys of newborn rats. The kidneys of fetuses whose mother received a type 1 AII receptor (AT1) antagonist during gestation present several morphological alterations. Mutations in genes that encode components of the renin-angiotensin system are associated with autosomal recessive renal tubular dysgenesis. Morphological changes were detected in the kidneys of 3-week-old angiotensin-deficient mice. Mitogen-activated protein kinases (MAPKs) are important mediators that transduce extracellular stimuli to intracellular responses. The MAPK family comprises three major subgroups, namely extracellular signal-regulated protein kinase (ERK), c-jun N-terminal kinases (JNK), and p38 MAPK (p38). Important events in renal growth during nephrogenesis such as cellular proliferation and differentiation accompanied by apoptosis on a large scale can be mediated by MAPK pathways. A decrease in glomerulus number was observed in embryos cultured for 48 and 120 h with ERK or p38 inhibitors. Many effects of AII are mediated by MAPK pathways. Treatment with losartan during lactation provoked changes in renal function and structure associated with alterations in AT1 and type 2 AII (AT2) receptors and p-JNK and p-p38 expression in the kidney. Several studies have shown that AII and MAPKs play an important role in renal development. However, the relationship between the effects of AII and MAPK activation on renal development is still unclear.

Effects of quinazolinones on the development of Balb/C mice embryonic kidneys

Quinazolinones are heterocyclic components [able to form cyclized compounds] which have several medical effects such as anti-malarial, spasmolytic, anti-microbial, sedative, etc. They are also known for their fungicidal properties, inhibition of tyrosine-kinase and DNA repair enzyme poly [ADP-ribose] polymerase [PARP] and are also effective in treatment of cancer, diabetes, and parkinsonism complications. In this study, for the first time different aspects of developmental effects of two new Quinazolinone components [QPPE and QEPE], on kidneys of Balb/C mice embryos were investigated. Pregnant Balb/C mice were divided into four groups of control [n=30], sham [n=30], experimental 1 [n=30] and experimental 2 [n=30]. Control mice remained intact, sham and two experimental groups received 0.05% methyl cellulose and 100 mg/kg/body weight [most effective dose] of QPPE and QEPE, intraperitoneally [IP], on day 10th of gestation. Kidneys were removed by c-sections, stained with H and E, PAS, trichrome, reticholin and jones staining. Some embryonic kidneys were prepared for measurements of level of alkaline phosphatase and TEM studies. Light and TEM microscopes, and level of enzyme surveys demonstrated that QPPE and QEPE are toxic components, creating protrusions at the surface of convoluted proximal tubules, protein casts, renal necrotic cells, pseudothyroidezation, mitochondria degeneration, hyperemia, glomeruli hypertrophy, widening of renal spaces, vacuolization, as well as decrease in the number of brush border villi and level of alkaline phosphatase. By being teratogens and toxins, these two new derivatives affected development of embryonic kidneys at histological, biochemical and intracellular levels; QEPE had more effects and convoluted proximal tubules were more sensitive than convoluted distal tubules

Expression of cell adhesion molecules in the normal and T3 blocked development of the tadpole's kidney of Bufo arenarum (Amphibian, Anuran, Bufonidae) / Expressão das moléculas de adesão celular no desenvolvimento normal e com a inibição do hormônio tireoidea do rim nas larvas do Bufo arenarum (Amphibia, Anura, Bufonidae)

Cell adhesion molecules act as signal transducers from the extracellular environment to the cytoskeleton and the nucleus and consequently induce changes in the expression pattern of structural proteins. In this study, we showed the effect of thyroid hormone (TH) inhibition and arrest of metamorphosis on the expression of E-cadherin, β-and α-catenin in the developing kidney of Bufo arenarum. Cell adhesion molecules have selective temporal and spatial expression during development suggesting a specific role in nephrogenesis. In order to study mechanisms controlling the expression of adhesion molecules during renal development, we blocked the B. arenarum metamorphosis with a goitrogenic substance that blocks TH synthesis. E-cadherin expression in the proximal tubules is independent of thyroid control. However, the blockage of TH synthesis causes up-regulation of E-cadherin in the collecting ducts, the distal tubules and the glomeruli. The expression of β-and α-catenin in the collecting ducts, the distal tubules, the glomeruli and the mesonephric mesenchyme is independent of TH. TH blockage causes up-regulation of β-and α-catenin in the proximal tubules. In contrast to E-cadherin, the expression of the desmosomal cadherin desmoglein 1 (Dsg-1) is absent in the control of the larvae kidney during metamorphosis and is expressed in some interstitial cells in the KClO4 treated larvae. According to this work, the Dsg-1 expression is down-regulated by TH. We demonstrated that the expression of E-cadherin, Dsg-1, β-catenin and α-catenin are differentially affected by TH levels, suggesting a hormone-dependent role of these proteins in the B. arenarum renal metamorphosis.

Moléculas de adesão celular atuam como tradutores do ambiente extracelular para o citoesqueleto e o núcleo e, conseqüentemente, induzindo mudanças no padrão da expressão das proteínas estruturais. Neste estudo, observamos os efeitos da inibição do hormônio tireóidea (TH) e detenção da metamorfose na expressão da E-caderina, β- e α- catenina no desenvolvimento do rim do Bufo arenarum. As moléculas de adesão celular durante o desenvolvimento têm uma expressão temporal e espacial seletiva, sugerindo um papel específico na nefrogênese. Com o propósito de estudar os mecanismos de controle da expressão das moléculas de adesão durante o desenvolvimento renal, bloqueou-se a metamorfose do B. arenarum com uma substancia goitrogênica que bloqueia a síntese de TH. A expressão da E-caderina nos tubos proximais é independente do controle da tireóide. Entretanto, o bloqueio da síntese de TH provoca uma sobre elevação da E-caderina nos dutos coletores, nos tubos distais e nos glomérulos. A expressão da β- e α-catenina nos dutos coletores, nos tubos distais, nos glomérulos e no mesênquima mesonéfrico é independente da TH. O bloqueio da TH causa uma sobre-regulação da β- e α-catenina nos tubos proximais. Em contraste com a E-caderina, a expressão da caderina desmossomal demogloína 1 (Dsg-1) é ausente no controle durante a metamorfose da fase larval dos rins e se expressa em algumas células intersticiais nas larvas tratadas com KClO4. De acordo com este trabalho, a expressão Dsg-1 é subregulada pela TH. Demonstramos que a expressão da E-caderina, Dsg-1, β-catenina e α-catenina são afetadas de forma diferencial pelos níveis de TH, sugerindo um dependência hormonal destas proteínas na metamorfose renal do B. arenarum.

Fetal development of regulatory mechanisms for body fluid homeostasis

The balance of body fluids is critical to health and the development of diseases. Although quite a few review papers have shown that several mechanisms, including hormonal and behavioral regulation, play an important role in body fluid homeostasis in adults, there is limited information on the development of regulatory mechanisms for fetal body fluid balance. Hormonal, renal, and behavioral control of body fluids function to some extent in utero. Hormonal mechanisms including the renin-angiotensin system, aldosterone, and vasopressin are involved in modifying fetal renal excretion, reabsorption of sodium and water, and regulation of vascular volume. In utero behavioral changes, such as fetal swallowing, have been suggested to be early functional development in response to dipsogens. Since diseases, such as hypertension, can be traced to fetal origin, it is important to understand the development of fetal regulatory mechanisms for body fluid homeostasis in this early stage of life. This review focuses on fetal hormonal, behavioral, and renal development related to regulation of body fluids in utero.

Regeneration of kidney tissue using in vitro cultured fetal kidney cells

Transplanting fetal kidney cells (FKCs) can regenerate kidney. This requires in vitro expansion in cell number to acquire enough cells for transplantation. However, FKCs may change their cellular characteristics during expansion and, thus, may not regenerate kidney tissue upon transplantation. We investigated how cell culture period affects cellular characteristics and in vivo regenerative potential of FKCs. As the passage number increased, cell growth rate and colony forming ability decreased while senescence and apoptosis increased. To examine in vivo regenerative potential, FKCs cultured through different numbers of passages were implanted into the parenchyma of kidneys of immunodeficient mice using fibrin gel for 4 wk. Histological analyses showed passage-dependent kidney tissue regeneration, and the regeneration was better when cells from lower number of passages were implanted. This result shows that in vitro culture of FKCs significantly affects the cell characteristics and in vivo tissue regenerative potential.

Polycystin-1 Expression in Fetal, Adult and Autosomal Dominant Polycystic Kidney

The mutation of the PKD1 gene causes autosomal dominant polycystic kidney disease (ADPKD), and the PKD1 gene encodes polycystin-1 (PC-1). PC-1 is thought to be a cell-cell/matrix adhesion receptor molecule at the cell surface that is widely expressed in the kidney. However, there are controversies about the role of PC-1 protein and its expression when using different antibodies to detect it. We used two PC-1 antibodies; C-20 (Santa Cruz, sc-10372) as the C-terminal antibody, and P-15 (Santa Cruz, sc-10307) as the N-terminal antibody. We evaluated the PC-1 expression by performing immunoblotting on the human embryonic kidney (HEK) 293 cells and the renal proximal tubular epithelial cell (RPTEC) lysates. We characterized the expression of PC-1 in the fetal, adult and polycystic kidneys tissues by performing immunohistochemistry. We confirmed the PC-1 expression in the HEK 293 cells and the RPTEC lysates, but the expression was very low. The PC-1 proteins were diffusely expressed in the tubular epithelial cells cytoplasm in the fetal and adult kidneys, and the PC-1 expression was more prominent in the proximal tubules of the fetal kidney. In the ADPKD kidney, the PC-1 proteins were heterogenously and weakly expressed in the tubular or cyst lining epithelial cells. Our data suggests that the development of the kidney may regulate the expression of PC-1, and an altered PC-1 expression may contribute to cyst formation in ADPKD.

Obtención y caracterización de una línea celular diploide de riñón humano / Obtention and characterization of a diploid cell line of human kidney

Se obtuvo una nueva línea celular diploide de riñón embrionario humano mediante subcultivos seriados (Mag) a partir de un cultivo primario. Se preparó aplicando la técnica de explanto en lugar de la clásica digestión enzimática con tripsina. El proceso de estabilización de la línea diploide luego del ôcultivo secundarioö se alcanzó entre los pases 6 y 7. Fueron probados 3 medios de cultivo durante el proceso, demostrándose que solo el MEM fue completamente satisfactorio. Las características biológicas de la nueva línea fueron: morfología fibroblástica, medio de cultivo Eagle MEM con 10 por ciento de SBF, split 1:2 a 1:3, cariotipo humano normal, viabilidad poscongelación de 60 por ciento, libre de contaminantes y no tumorigénica. Los subcultivos 11-13 de Mag criopreservados fueron estudiados desde el punto de vista de su utilidad para el diagnóstico de diferentes grupos virales

Effects of sodium cyclamate in kidneys of rats fetuses: a morphometric study

El ciclamato es usado como edulcorante no calórico en muchos alimentos y bebidas y es 30 veces mas dulce que la sacarosa, sin el gusto amargo de la sacarina. Aparecen en su composición, los productos como ciclamato de sodio, ciclamato de calcio y acido ciclamico. El objetivo del trabajo fue evaluar los efectos del ciclamato de sodio en ri¤ones de fetos de ratas, considerandose las alteraciones morfometricas en glomerulo, túbulos contornados proximal y distal y conducto coletor. Fueron utilizadas 10 ratas adultas (Rattus norvegicus) variedad Wistar, con peso medio de 238 g, 5 ratas para el grupo control y 5 ratas tratadas con ciclamato de sodio. Entre el 10 y 14 dia de la pre¤ez, 5 ratas recibieron una inyección diaria intraperitoneal de 60mg/Kg/dia de ciclamato de sodio durante 5 dias. En el 20 dia, los animales fueron sacrificados y los fetos fijados en solución de Alfac, incluidos en parafina, cortados y te¤idos com H-E. El método utilizado fue la morfometría por la técnica cariométrica. Hubo disminución significativa en los pesos de los fetos y de la placenta en el grupo tratado con ciclamato de sodio (p= 0,004) comparado con el grupo control. En el volumen glomerular y tama¤o nuclear de las celulas de los túbulos contornados proximal, distal y conducto colector del ri¤ón fetal de las ratas tratadas con ciclamato de sodio, hubo aumento estadisticamente significativo. Los resultados mostraron que el uso del ciclamato de sodio produjo la reducción del peso de los fetos, placenta y longitud del cordón umbilical. Hubo aumento significativo en el volumen glomerular y en el tama¤o nuclear de las células de los túbulos contornados proximal, distal y conducto colector, sugerente de nefrotoxicidad.