Mineral bone disorder and osteoporosis in hemodialysis patients

Abstract Background: Bone disease is common in patients undergoing hemodialysis. It is the result of bone turnover abnormalities and the decrease of bone mineral density (BMD). We aimed to determine the usefulness of serum bone turnover markers and BMD measurement by dual-energy x-ray absorptiometry (DXA) in hemodialysis patients. Methods: We conducted a cross-sectional study including 90 hemodialysis for more than 12 months. Bone mineral density was assessed by DXA. Peripheral blood samples were obtained from each patient before dialysis in a fasting state within a week of the DXA. Biochemical variables of calcium and phosphate were measured. One bone formation marker (bone-specific alkaline phosphatase (bAP), one bone resorption marker (carboxy-terminal telopeptides of type 1 collagen (CTX)) were measured. Total alkaline phosphatase (TAP), intact parathyroid hormone (PTH) and fibroblast growth factor 23 (FGF23) which is a bone-derived hormone were also measured. Results: CTX values were 6.25 times higher than the normal limit of the assay. Bone alkaline phosphatase levels were less than 10 ng/mL in 28.8% of cases. 23% of patients have osteoporosis and 45% have osteopenia. Femoral BMD had negative correlations with age and PTH levels. FGF23 levels were significantly increased in patients with osteoporosis affecting the lumbar. The levels of bAP and CTX showed a positive correlation. Both circulating bAP and CTX levels showed also positive correlations with PTH levels. Fractures, observed in 12.2% of cases, were associated with low PTH values and the existence of osteoporosis. Conclusions: Our study showed that osteoporosis and fracture are common in dialysis patients. The reduced BMD was associated with advanced age and elevated levels of PTH. Markers of bone turnover and FGF23 may play a role in the diagnosis of bone disease in hemodialysis patients. DXA measurement is necessary for the monitoring for bone loss.(AU)

DNA hypermethylation of Fgf16 and Tbx22 associated with cleft palate during palatal fusion

Abstract Objective: Cleft palate (CP) is a congenital birth defect caused by the failure of palatal fusion. Little is known about the potential role of DNA methylation in the pathogenesis of CP. This study aimed to explore the potential role of DNA methylation in the mechanism of CP. Methodology: We established an all-trans retinoic acid (ATRA)-induced CP model in C57BL/6J mice and used methylation-dependent restriction enzymes (MethylRAD, FspEI) combined with high-throughput sequencing (HiSeq X Ten) to compare genome-wide DNA methylation profiles of embryonic mouse palatal tissues, between embryos from ATRA-treated vs. untreated mice, at embryonic gestation day 14.5 (E14.5) (n=3 per group). To confirm differentially methylated levels of susceptible genes, real-time quantitative PCR (qPCR) was used to correlate expression of differentially methylated genes related to CP. Results: We identified 196 differentially methylated genes, including 17,298 differentially methylated CCGG sites between ATRA-treated vs. untreated embryonic mouse palatal tissues (P<0.05, log2FC>1). The CP-related genes Fgf16 (P=0.008, log2FC=1.13) and Tbx22 (P=0.011, log2FC=1.64,) were hypermethylated. Analysis of Fgf16 and Tbx22, using Gene Ontology (GO) and the Kyoto Encyclopedia of Genes and Genomes (KEGG), identified 3 GO terms and 1 KEGG pathway functionally related to palatal fusion. The qPCR showed that changes in expression level negatively correlated with methylation levels. Conclusions: Taken together, these results suggest that hypermethylation of Fgf16 and Tbx22 is associated with decreased gene expression, which might be responsible for developmental failure of palatal fusion, eventually resulting in the formation of CP.

Elevated levels of plasma osteoprotegerin are associated with all-cause mortality risk and atherosclerosis in patients with stages 3 to 5 chronic kidney disease

Osteoprotegerin (OPG) regulates bone mass by inhibiting osteoclast differentiation and activation, and plays a role in vascular calcification. We evaluated the relationship between osteoprotegerin levels and inflammatory markers, atherosclerosis, and mortality in patients with stages 3-5 chronic kidney disease. A total of 145 subjects (median age 61 years, 61% men; 36 patients on hemodialysis, 55 patients on peritoneal dialysis, and 54 patients with stages 3-5 chronic kidney disease) were studied. Clinical characteristics, markers of mineral metabolism (including fibroblast growth factor-23 [FGF-23]) and inflammation (high-sensitivity C-reactive protein [hsCRP] and interleukin-6 [IL-6]), and the intima-media thickness (IMT) in the common carotid arteries were measured at baseline. Cardiac function was assessed by color tissue Doppler echocardiography. After 36 months follow-up, the survival rate by Kaplan-Meier analysis was significantly different according to OPG levels (χ 2=14.33; P=0.002). Increased OPG levels were positively associated with IL-6 (r=0.38, P<0.001), FGF-23 (r=0.26, P<0.001) and hsCRP (r=0.0.24, P=0.003). In addition, OPG was positively associated with troponin I (r=0.54, P<0.001) and IMT (r=0.39, P<0.0001). Finally, in Cox analysis, only OPG (HR=1.07, 95%CI=1.02-1.13) and hsCRP (HR=1.02, 95%CI=1.01-1.04) were independently associated with increased risk of death. These results suggested that elevated levels of serum OPG might be associated with atherosclerosis and all-cause mortality in patients with chronic kidney disease.

Tumor mesenquimatoso fosfatúrico de fosa nasal con compromiso intracraneano: reporte de un caso y revisión de la literatura / Nasal fossa phosphaturic mesenchymal tumor with intracraneal compromise: case report and review of the literature

El tumor mesenquimatoso fosfatúrico (TMF) es una enfermedad extremadamente rara. Según evidencia reciente es causado por la sobreexpresión del factor de crecimiento fibroblástico 23 (FGF23), el cual genera hipofosfemia y osteomalacia. A continuación presentamos el caso de un paciente de 42 años con un tumor mesenquimatoso fosfatúrico de fosa nasal izquierda con extenso compromiso intracraneano. Cabe destacar que hasta la fecha hay 142 casos reportados de TMF en la literatura de los cuales solo 11 se ubican en fosa nasaly cavidades sinusales, y sólo dos de ellos ubicados en fosa nasal¹. El paciente tuvo una exitosa resolución quirúrgica con la consecuente normalización de parámetros analíticos (incluido el FGF23), mejoría sintomática y ausenia de recidiva hasta la fecha.

The phosphaturic mesenchymal tumor (PMT) is an extremely rare disease. According to recent evidence is caused by overexpression of fibroblast growth factor 23 (FGF23) which generates hypophosphatemia and osteomalacia. We report the case of a 42 year old patient with a left nasal fossa phosphaturic mesenchymal tumor with intracranial involvement. Should be noted that to date there are 142 reported cases of PMT in the literature of which only 11 are located in nasal fossa and sinus cavities, two of them located in nasal fossa¹. The patient had a successful surgical resolution with consequent normalization of analytical parameters (including FGF23), absence of symptoms and no recurrence to date.

Evaluation of epithelial cell proliferating activity and fibroblast nuclear kariometry in recurrent pterygium treated with mitomycin C / Avaliação da atividade proliferativa das células epiteliais e da cariometria do núcleo dos fibroblastos em pterígios recidivados previamente tratados com a mitomicina C

PURPOSE: To evaluate the effectiveness of mitomycin C (MMC) in preventing recurrence of pterygium following conjunctival autograft transplantation (CAT). Ki-67 antigen to evaluate epithelial cell proliferation and fibroblast nuclear kariometry were used to assist treatment evaluation. METHODS: Twenty-nine patients with recurrent pterygium were divided into three groups: Group (G) 1 - CAT and placebo eyedrops (PED); G2 - CAT, 0.015 percent MMC subconjunctivally, and PED; G3 - CAT and 0.02 percent MMC eyedrops. Immunohistochemistry for the Ki-67 antigen and fibroblast nuclei kariometry were performed on the excised tissue, divided into nasal and temporal sides. Kariometry was evaluated in terms of volume (Vl) and area (Ar) using at least 50 cells/patient. RESULTS: The percentage of positive epithelial cells for the Ki-67 antigen on the nasal and temporal side after treatment of the three groups were: nasal (5.39 percent G1, 4.49 percent G2, and 3.88 percent G3); temporal (3.30 percent G1, 4.46 percent G2, 4.14 percent G3), did not show significant differences. Fibroblast nucleus kariometry was: nasal Vl (792.1 µ3 G1, 605.1 µ3 G2, and 549.9 µ3 G3) and Ar (100.58 µ2 G1, 83.13 µ2 G2, and 78.41 µ2 G3). The three groups showed significant differences: p=0.039 and p=0.035, for respectively Vl and Ar, on the nasal side. After a six month of treatment, the three groups presented the following recurrence rates: G1, 22.22 percent, G2, 18.18 percent and G3, 33.33 percent, respectively. CONCLUSION: MMC did not reduce the number of positive epithelial cells for the Ki-67 antigen in recurrent pterygium, but decreased fibroblast nucleus volume and area on the nasal side of the pterygia. The number of positive epithelial cells for the Ki-67 antigen seemed not to be related to pterygium recurrence observed over a six-month post-surgery period. The role of epithelial cell proliferation in pterygium recurrence should be evaluated by further studies.

OBJETIVO: Avaliar a eficácia da mitomicina C (MMC) na prevenção da recorrência quando previamente utilizada no transplante autólogo de conjuntiva (TAC). A avaliação da proliferação celular epitelial pelo antígeno Ki-67 e a cariometria do núcleo dos fibroblastos foram usados como auxiliares na avaliação do tratamento. MÉTODOS: Vinte e nove pacientes com pterígio recidivado foram divididos em três grupos: Grupo (G) 1-TAC e colírio placebo (PLA); G2-TAC, MMC 0,015 por cento subconjuntival e PLA; G3-TAC e colírio de MMC 0,02 por cento. A imuno-histoquímica foi realizada no tecido excisado para o antígeno Ki-67, como a cariometria dos núcleos dos fibroblastos (divididos em lado nasal e temporal). A cariometria dos núcleos dos fibroblastos foi avaliada de acordo com os seguintes parâmetros: volume (Vl) e área (Ar) em pelos menos 50 células por paciente. RESULTADOS: A porcentagem das células epiteliais positivas para o antígeno Ki-67 no lado nasal e temporal após o tratamento dos três grupos estudados foi: nasal (3,30 por cento G1, 4,49 por cento G2 e 3,38 por cento G3) e temporal (3,30 por cento G1, 4,46 por cento G2 e 4,14 por cento G3) não mostrando diferença significativa. A cariometria do núcleo dos fibroblastos foi: Vl nasal (792,1 µ3 G1, 605,1 µ3 G2, e 549,9 µ3 G3) e a Ar (100,58 µ2 G1, 83,13 µ2 G2, e 78,41 µ2 G3). Os três grupos mostraram uma diferença significativa p=0,039 e p=0,035, respectivamente do Vl e da Ar no lado nasal. Após seis meses de tratamento, os três grupos apresentaram a seguinte taxa de recidiva: 22,22 por cento G1, 18,18 por cento, G2 e 33,33 por cento G3 respectivamente. CONCLUSÃO: O uso da MMC não interferiu nas células epiteliais positivas para o antígeno Ki-67 no pterígio recidivado, mas acarretou diminuição do volume e área dos núcleos dos fibroblastos no lado nasal do pterígio. As células epiteliais positivas para o antígeno Ki-67 parecem não ter relação com a recidiva do pterígio após seis meses...

Protein expression of VEGF, IGF-1 and FGF in retroocular connective tissues and clinical correlation in Graves' ophthalmopathy / Expressão protéica de VEGF, IGF-1 e FGF no tecido conjuntivo retro-ocular e correlação clínica na oftalmopatia de Graves

PURPOSE: To investigate the immunohistochemical expression (IGF-1, EGFr, EGF, c-erbB-2/HER-2/neu, PDGF-A, PDGF-B, FGF and VEGF) in patients with Graves' ophthalmopathy. METHODS: Twenty-four samples (Graves' ophthalmopathy patients) underwent lateral rectus muscle and surrounding fibrous and adipose tissue biopsy. The control group was obtained by strabismus surgery. Correlation between clinical- ophthalmologic, endocrinological, ultrasonographic findings, and immunohistochemical expression was performed. RESULTS: IGF-1: There were 7 positive cases (29.2 percent). There was a direct relation with higher CAS (clinical activity score) in all of them and if only CAS equal or higher than 5 was considered, this was 54.5 percent. FGF: There was expression in 5 cases (20.8 percent) with a direct relation in all those with higher CAS (>5) (45.4 percent). VEGF: There were two positive cases (8.3 percent) for VEGF in endothelial cells, in these cases the patients also presented CAS higher than 5. There was no expressions of all growth factors in the control group. CONCLUSIONS: All patients, except one, with positive expression of FGF, IGF-1 and VEGF showed CAS greater than 5, suggesting in this way an important role of these growth factors in the pathogenesis and severity of Graves' ophthalmopathy. However, statistical analysis revealed only significant association between IGF-1 and male sex (P=0.034). Low ultrasound reflectivity and endocrine status may not correlate directly with disease activity or with immunoexpression of growth factors and c-erbB-2/HER-2/neu.

OBJETIVO: Investigar a expressão imuno-histoquímica de IGF-1, EGFr, EGF, c-erbB-2/HER-2/neu, PDGF-A, PDGF-B, FGF e VEGF na oftalmopatia de Graves. MÉTODOS: Vinte e dois pacientes (oftalmopatia de Graves) foram submetidos à biópsia do músculo reto lateral e tecido fibroso e adiposo adjacente. O grupo controle foi de pacientes de cirurgia de estrabismo. Foi feita correlação entre achados clínico-oftalmológicos, endocrinológicos, ultra-sonográficos e da expressão imuno-histoquímica dos fatores de crescimento. RESULTADOS: IGF-1: Houve 7 casos positivos (29,2 por cento). Houve correlação direta com o CAS (clinical activity score) elevado em todos os casos e em que consideramos CAS apenas acima de 5, em 54,5 por cento. FGF: Houve expressão em 5 casos (20,8 por cento) com relação direta com CAS elevado em todos os casos e em que consideramos CAS maior que 5 (45,4 por cento). VEGF: Houve dois casos positivos (8,3 por cento) para VEGF nas células endoteliais e estes casos também apresentavam CAS maior que 5. A imunorreatividade foi negativa em todo grupo controle. CONCLUSÃO: Todos os pacientes, com exceção de um, com expressão positiva para FGF, IGF-1 e VEGF mostraram CAS maior que 5, sugerindo importante papel destes fatores de crescimento na patogênese e gravidade da oftalmopatia de Graves. Entretanto, a análise estatística demonstrou associação significativa entre IGF-1 e o sexo masculino (P=0,034). Baixa refletividade ao ultra-som e condição endócrina não estiveram correlacionadas.

Respuesta in vitro de fibroblastos de piel genital humana a andrógenos / In vitro response of fibroblasts from genital skin to androgens

Mutaciones en el gen del receptor de andrógenos (Xq 11-12) originan insensibilidad a estos esteroides. El cultivo de fibroblastos de piel genital permite analizar in vitro la capacidad de respuesta a andrógenos de los individuos, ya que dichas células expresan el receptor para el esteroide; en nuestro medio no se realiza este tipo de estudios. El objetivo de este trabajo fue establecer dicha metodología y estudiar las propiedades de unión y de respuesta a andrógenos de individuos 46XY normales, con hipospadia o con resistencia a andrógenos. Las células en cultivo demostraron las propiedades características de fibroblastos, con propiedades de unión de andrógenos comparables a las descritas por otros autores. El promedio del valor de la constante de disociación fue 4,02ñ3,4 x 10-10 M. La unión máxima en el grupo control (41,3ñ23 fmol/mg proteína), no fue en promedio, diferente a los grupos con hipospadia y resistencia a andrógenos (39,3ñ32 y 34,1ñ20, respectivamente), pero la unión luego de un tramiento con andrógenos (24 h), fue mayor en el grupo control. Se concluye que esta técnica es práctica para la medición de algunos parámetros, necesarios para el diagnóstico de desórdenes asociados a defectos de la acción de andrógenos