Parenteral succinate reduces levels of reactive oxygen species without changing serum caspase-3 levels in septic rats.

INTRODUCTION: Sepsis is a syndrome of physiological, pathological, and biochemical disorders with several processes co-occurring; reactive oxygen species (ROS) production and apoptosis are 2 of them. Succinate is a Krebs cycle intermediate that is oxydized in complex II of the mitochondria. This study aims to investigate the influence of succinate infusion on these processes. MATERIAL AND METHODS: Sepsis was induced with caecal ligation and puncture in 200 gr Sprague Dawley rats. Four groups were formed with 10 animals (1 - control, 2 - succinate, 3 - sepsis, and 4 - sepsis + succinate). 5 mmol kg-1 of intraperitoneal succinate were administered twice in groups 2 and 4. ROS and caspase-3 levels were measured. RESULTS: Overall, ROS levels (P = 0.017), but not caspase-3 levels (P = 0.89) differed significantly between the groups. The succinate administration reduced serum ROS levels (group 4 vs. 3) in a statistically significant way [0.0623 units (95% CI: 0.0547-0.0699) vs. 0.0835 (0.06-0.106), P = 0.017)], but it did not reduce serum caspase-3 levels (P = 0.39). There was no correlation between serum ROS levels and serum caspase-3 levels. CONCLUSIONS: In this model, ROS levels were reduced with succinate infusion, but caspase-3 levels were not. In addition, ROS levels and apoptosis levels are not correlated, which suggests that those processes occur at different times.

Serum reactive oxygen species and apoptosis markers in septic patients.

INTRODUCTION: Oxidative stress is one of the pathophysiological processes that occur during sepsis. Reactive oxygen species (ROS) production causes lipid peroxidation and protein and DNA damage. ROS and DNA damage triggers apoptosis. Several studies have shown that organ failure in sepsis is mediated by apoptosis. The aim of this study is to investigate the levels of serum ROS and serum caspase-3 in septic patients and healthy volunteers, and their correlation. MATERIAL AND METHODS: Serum samples were taken within the first 12 hours of ICU stay. The dichlorofluorescein technique was used to determine serum ROS levels, and the ELISA technique was used to quantify serum caspase-3 in septic patients and healthy volunteers. RESULTS: There was no difference in serum ROS levels between healthy volunteers and septic patients (P = 0.26), and there was a significant difference in serum caspase-3 levels between healthy volunteers and septic patients (P < 0.001). There was no difference between patients who lived and died in the intensive care unit (ICU) in serum ROS (P = 0.089) and serum caspase-3 (P = 0.18). There was no correlation between both markers (R = -0.0013, P = 0.98). CONCLUSIONS: We conclude that there is no correlation between serum ROS and caspase-3; therefore, both processes might not be associated during the first hours of ICU stay.

Early decrease in the podocalyxin to synaptopodin ratio in urinary Fabry podocytes.

BACKGROUND: In Fabry nephropathy, podocyturia is an early event that may lead to glomerulosclerosis and chronic kidney disease. The glycocalyx is a potential podocyte damaged compartment in glomerulopathies. We investigated glycocalyx podocalyxin in urinary detached podocytes compared with cytoplasmic synaptopodin. METHODS: This was a cross-sectional study including 68 individuals: Controls (n = 20) and Fabry patients (n = 48), 15 untreated and 33 treated. Variables included age, gender, urinary protein/creatinine ratio (UPCR), estimated glomerular filtration rate (eGFR), lyso-triasocylsphingosine (lyso-Gb3) levels and enzyme replacement therapy (ERT). Podocyturia was assessed by immunofluorescence and podocyte subpopulations were analyzed. RESULTS: Fabry patients displayed higher podocyturia than controls. Fabry treated subjects (n = 33) presented significantly higher UPCR compared with untreated ones (n = 15); podocyturia, eGFR and lyso-Gb3 levels were not different. All control podocytes colocalized synaptopodin and podocalyxin; 13 Fabry patients (27%) colocalized these proteins, while 35 (73%) were only synaptopodin positive. No podocalyxin-positive/synaptopodin-negative cells were encountered. In Fabry patients, podocyturia was significantly higher and proteinuria lower in those that colocalized. CONCLUSION: Fabry patients present higher podocyturia and a presumably more damaged glycocalyx assessed by podocalyxin. Treated patients had significant higher proteinuria suggesting ERT is initiated late, at advanced stages. The degree of podocalyxin-negative podocytes was similar in both groups, but colocalization was associated with lower proteinuria. Podocyturia assessed by podocalyxin alone may be underestimated. The implications of podocyte glycocalyx damage deserve further investigations.

Estenosis de las arterias cubital y radial en pacientes con esclerosis sistémica, comparado con un grupo control / Ulnar and radial stenosis in systemic sclerosis

Objetivos: describir la frecuencia de estenosis arterial (cubital y radial) en pa-cientes con esclerosis sistémica (ES); analizar la relación entre estenosis macro-vascular y úlceras digitales. Método: se incluyeron 57 pacientes con ES, según la clasificación del Colegio Americano de Reumatología de 1980 y 21 pacientes sin ES. Se realizó ecografía doppler arterial de miembros superiores. Resultados: la estenosis en al menos una arteria cubital se objetivó en 31% de pacientes con ES (18/57) (p=0.003). Se objetivó estenosis radial en 9 de 57 pacientes con ES (15%) y en uno de los 21 controles (p=0.19). En el modelo multivariado, los predicto-res de úlceras digitales fueron inicio de Raynaud antes de los 40 años (OR 5.3 IC95% 1.54-18.22, p=0.008) y patrón tardío en la capilaroscopia (OR 4.4 IC95% 1.29-15.63, p=0.018). Conclusiones: un tercio de los pacientes ES presentó este-nosis cubital. El compromiso de los grandes vasos no se asoció a úlceras digitales.

Objectives: to describe the frequency of ulnar and radial stenosis in SSc patients. Analyze the correlation between arterial stenosis and digital ulcers. Methods: we included 57 SSc consecutive patients who fulfilled ACR 1980 classification criteria, and 21 healthy controls. An arterial ecodoppler was performed to all participants. Results: the presence of stenosis in at least one ulnar artery was observed in 18 of 57 patients with SSc (31%) and in none of the 21 controls (p=0.003). Stenosis was present in at least one radial artery in 9 of 57 SSc patients (15%) (p=0.19). In multivariate model, the best predictors of digital ulcers were age at onset of Ray-naud phenomenon before 40 years (OR 5.3 95%CI 1.54-18.22, p=0.008) and late SD pattern (OR 4.4 95%CI 1.29-15.63, p=0.018). Conclusion: in the present series, ulnar stenosis was observed frequently in SSc patients. Stenosis of large vessels was not associated with digital ulcers.

Revisión: ¿Qué hacer con un test positivo para anticuerpos antinucleares en Pediatría? / Review: What to do with a positive antibody test antinuclear in pediatrics?

La presencia de anticuerpos antinucleares (ANA) es el denominador común de muchas enfermedades autoinmunes sistémicas. Su presencia puede ser indicativa de una enfermedad reumática; sin embargo, estos autoanticuerpos también pueden estar presentes en individuos sanos o con infecciones. El objetivo del presente trabajo es presentar un paciente con dolor musculoesquelético y ANA positivos. En ausencia de una sintomatología que haga sospechar una enfermedad reumática, la positividad de los ANA no tiene significado diagnóstico

The antinuclear antibodies are present in many systemic autoimmune diseases. Their presence may be indicative of a rheumatic disease; however, these autoantibodies may also be present in healthy children or infections. We present a patient with musculoskeletal pain and ANA positivity. When definite signs and symptoms have not been developed, the ANA positivity has no diagnostic significance

In IgA Nephropathy, Glomerulosclerosis Is Associated with Increased Urinary CD80 Excretion and Urokinase-Type Plasminogen Activator Receptor-Positive Podocyturia.

BACKGROUND: Podocyturia may determine the evolution to podocytopenia, glomerulosclerosis, and renal failure. According to the Oxford classification of IgA nephropathy (IgAN), the S1 lesion describes glomerulosclerosis. Urokinase-type plasminogen activator receptor (uPAR) participates in podocyte attachment, while CD80 increases in glomerulosclerosis. We measured uPAR-positive urinary podocytes and urinary CD80 (uCD80) in controls and in IgAN subjects with M1E0S0T0 and M1E0S1T0 Oxford scores to assess a potential association between podocyturia, inflammation, and glomerulosclerosis. METHODS: The groups were as follows: controls (G1), n = 20 and IgAN group (G2), n = 39, subdivided into M1E0S0T0 (G2A), n = 21 and M1E0S1T0 (G2B), n = 18. Among the included variables, we determined uPAR-positive podocytes/gram of urinary creatinine (gUrCr) and uCD80 ng/gUrCr. Biopsies with interstitial fibrosis and tubular atrophy <10% were included. RESULTS: Groups were not different in age and gender; urinary protein-creatinine (uP/C) ratio, Chronic Kidney Disease-Epidemiology Collaboration (CKD-EPI) equation, uPAR-positive podocytes/gUrCr, and uCD80 were significantly increased in G2 versus G1. G2A and G2B were not different in age, gender, hypertension, and follow-up. G2B displayed significantly higher uP/C, uPAR-positive podocytes, uCD80, and lower CKD-EPI versus G2A. Strong significant correlations were encountered between uCD80 and podocyturia in G2A and G2B. However, when G1 was compared to G2A and G2B separately, the differences with respect to uP/C, uPAR-positive podocytes, and podocyturia were significantly stronger versus G2B than versus G2A. CONCLUSIONS: IgAN presents elevated uCD80 excretion and uPAR-positive podocyturia, while CD80 correlates with podocyturia. Glomerulosclerosis (S1) at the time of biopsy is associated with higher uP/C, lower renal function, increased uPAR-positive podocyturia, and CD80 excretion, and is independent of M1. In IgAN, uPAR may participate in podocyte detachment.

Expression of uPAR in Urinary Podocytes of Patients with Fabry Disease.

Background. Despite enzyme replacement therapy, Fabry nephropathy still progresses. Podocyturia is an irreversible event that antedates proteinuria and leads to chronic renal failure. We evaluated a potential mechanism of podocyte detachment via the expression of the urokinase-type Plasminogen Activator Receptor (uPAR) in urinary podocytes of Fabry patients. Methods. This is a cross-sectional study that included controls (n = 20) and Fabry patients (n = 44) either untreated (n = 23) or treated with agalsidase-ß (n = 21). Variables. Variables are estimated glomerular filtration rate (eGFR), urinary protein : creatinine ratio, and urinary uPAR+ podocyte : creatinine ratio. uPAR mRNA expression in response to lyso-Gb3, a bioactive glycolipid accumulated in Fabry disease, was studied in cultured human podocytes. Results. Controls and Fabry patients had similar age, gender, and renal function. Urinary uPAR+ podocytes were higher in patients than in controls. Untreated patients were significantly younger; had more females, and presented lower urinary protein : creatinine ratios and significantly higher urinary uPAR+ podocytes than treated subjects. In treated patients, urinary uPAR+ podocytes correlated with urinary protein : creatinine ratio (ρ = 0.5; p = 0.02). Lyso-Gb3 at concentrations found in the circulation of Fabry patients increased uPAR expression in cultured podocytes. Conclusions. Urinary podocytes expressing uPAR are increased in Fabry patients, especially in untreated patients. The potential contribution of uPAR expression to podocyte detachment merits further studies.

Podocyturia is significantly elevated in untreated vs treated Fabry adult patients.

BACKGROUND: Proteinuria suggests kidney involvement in Fabry disease. We assessed podocyturia, an early biomarker, in controls and patients with and without enzyme therapy, correlating podocyturia with proteinuria and renal function. METHODS: Cross-sectional study (n = 67): controls (Group 1, n = 30) vs. Fabry disease (Group 2, n = 37) subdivided into untreated (2A, n = 19) and treated (2B, n = 18). Variables evaluated: age, gender, creatinine, CKD-EPI, proteinuria, podocyte count/10 20× microscopy power fields, podocytes/100 ml urine, podocytes/g creatininuria (results expressed as median and range). RESULTS: Group 1 vs. 2 did not differ concerning age, gender and CKD-EPI, but differed regarding proteinuria and podocyturia. Group 2A vs. 2B: age: 29 (18-74) vs. 43 (18-65) years (p = ns); gender: males n = 3 (16 %) vs. n = 9 (50 %). Proteinuria was significantly higher in Fabry treated patients, while CKD-EPI and podocyturia were significantly elevated in untreated individuals. Significant correlations: group 2A: age-proteinuria, ρ = 0.62 (p = 0.0044); age-CKD-EPI, ρ = -0.84 (p < 0.0001); podocyturia-podocytes/100 ml urine, ρ = 0.99 (p = 0.0001); podocyturia-podocytes/g creatininuria ρ = 0.86 (p = 0.0003), podocytes/100 ml urine-podocytes/g urinary creatinine, ρ = 0.84 (p = 0.0004); proteinuria-CKD-EPI, ρ = -0.68 (p = 0.0013). Group 2B: podocyturia-podocytes/100 ml urine, ρ = 0.88 (p < 0.0001); podocyturia-podocytes/g creatininuria, ρ = 0.84 (p < 0.0001); podocytes/100 ml urine-podocytes/g creatininuria, ρ = 0.94 (p < 0.0001); CKD-EPI-proteinuria, ρ = -0.66 (p = 0.0028). CONCLUSIONS: Patients with Fabry disease display heavy podocyturia; those untreated present significantly higher podocyturia, lower proteinuria and better renal function than those who are treated, suggesting that therapy may be started at advanced stages. Podocyturia may antedate proteinuria, and enzyme therapy may protect against podocyte loss.

Frecuencia de manifestaciones sistémicas en pacientes con síndrome de Sjögren primario en Argentina / Frequency of systemic manifestations in patients with primary Sjögren's syndrome in Argentina

Del 20–71% de los pacientes con síndrome de Sjögren (SS) desarrolla manifestaciones sistémicas. Objetivos: El objetivo fue evaluar las características clínicoserológicas y frecuencia la de manifestaciones sistémicas en pacientes con SS primario. Material y métodos: Estudio retrospectivo con revisión de historias clínicas de pacientes con Sd de Sjögren primario visitados en el Hospital Británico de Buenos Aires en el período desde Enero de 2000 a Agosto de 2008. Resultados: Se incluyeron 41 paciente que cumplían criterios de clasificación Europeoamericanos 2002 para SS, todos de sexo femenino. La edad media fue 57,85±12,42 años (rango 26–79). El tiempo de evolución fue de 9,28 años (rango 0,08–24). Treinta y tres (80,49%) presentaron manifestaciones sistémicas. Las más frecuentes fueron artritis, vasculitis cutánea y polineuropatía. Este grupo presentó más frecuentemente títulos de AAN ≥1/640 e hipocomplementemia; aunque no estadísticamente significativas. La frecuencia de manifestaciones sistémicas halladas fue mayor a la reportada en otras series. Conclusiones: Un abordaje multidisciplinario enfocado en las manifestaciones sistémicas debería ser el nuevo estándar para el manejo del SS (AU)

Twenty to 71% of patients with Sjögren's syndrome (SS) will develop systemic manifestations. Objective: to characterize the clinical-serological presentation and the frequency of systemic manifestations in patients with primary SS. Methods: Retrospective study including patients with SS visited in “Hospital Británico de Buenos Aires” during the period from January 2000 to August 2008.Results: Forty-one patients fulfilled the 2002 American-European classification criteria for SS. All patients were women. Mean age at enrollment was 57,85±12,42 years (range 26–79). Mean duration of the disease was 9,28 years (range 0,08–24). Thirty-three (80,49%) developed systemic manifestations. The most frequent were arthritis, cutaneous vasculitis and polyneuropathy. This group featured more frequently ANA titles ≥1/640 and hypocomplementemia; although no statistical significance was found. The frequency of systemic manifestations found was greater than reported in the literature.Conclusions: A multidisciplinary approach focusing also on systemic manifestations should be the new standard for management of SS (AU)

[Frequency of systemic manifestations in patients with primary Sjögren's syndrome in Argentina]. / Frecuencia de manifestaciones sistémicas en pacientes con síndrome de Sjögren primario en Argentina.

UNLABELLED: Twenty to 71% of patients with Sjögren's syndrome (SS) will develop systemic manifestations. OBJECTIVE: To characterize the clinical-serological presentation and the frequency of systemic manifestations in patients with primary SS. METHODS: Retrospective study including patients with SS visited in "Hospital Británico de Buenos Aires" during the period from January 2000 to August 2008. RESULTS: Forty-one patients fulfilled the 2002 American-European classification criteria for SS. All patients were women. Mean age at enrollment was 57.85 ± 12.42 years (range 26-79). Mean duration of the disease was 9.28 years (range 0.08-24). Thirty-three (80.49%) developed systemic manifestations. The most frequent were arthritis, cutaneous vasculitis and polyneuropathy. This group featured more frequently ANA titles ≥ 1/640 and hypocomplementemia; although no statistical significance was found. The frequency of systemic manifestations found was greater than reported in the literature. CONCLUSIONS: A multidisciplinary approach focusing also on systemic manifestations should be the new standard for management of SS.

The C677T thermolabile variant of methylene tetrahydrofolate reductase on homocysteine, folate and vitamin B12 in a hemodialysis center.

Homocysteine is a risk factor for cardiovascular disease. Mutations in a key enzyme in homocysteine metabolism, methylenetetrahydrofolate reductase, may contribute to hyperhomocysteinemia and alter folate and cobalamin levels. After starting hemodialysis, 10 mg oral folate daily and 500 micrograms intravenous methylcobalamin once weekly were prescribed to 27 hemodialysis patients (time on hemodialysis > or = 12 months) and two groups were defined: Group A normal; Group B heterozygous. Initial, third and twelfth month measurements of homocysteine, serum folate and vitamin B12 levels were collected and analyzed. Heterozygous state of methylenetetrahydrofolate reductase prevalence was 48% and homozygozity 4%. Hyperhomocysteinemia was present in both groups. Cobalamin final levels were significantly lower in Group B compared to Group A. Homocysteine, serum folate and cobalamin levels at third and twelfth month were significantly different from baseline levels but non-different between them in both groups. In Group B, vitamin B12 at third month was significantly higher than initial, but final measurements were not different from baseline determinations. In conclusion, the heterozygous prevalence of the enzyme in hemodialysis patients is similar to that reported in the general population; hyperhomocysteinemia is frequent in hemodialysis patients and final levels in heterozygous patients are significantly higher than in normal patients. Cobalamin levels are lower in the heterozygous group. After one year of treatment, homocysteine tends to increase, suggesting a secondary resistance phenomenon to vitamin supplementation in heterozygous patients.

Randomized trial of methylcobalamin and folate effects on homocysteine in hemodialysis patients.

BACKGROUND: There are no data available on the effects of intravenous (i.v.) methylcobalamin (Me-Cbl), the coenzymatically active form of vitamin B12 that acts as a cofactor for methionine synthase in the conversion of total homocysteine (tHcy) to methionine, with or without oral folic acid (FA) supplementation, on fasting tHcy levels in hemodialysis (HD) patients. METHODS: We performed a prospective randomized trial in which 62 chronic HD patients without previous vitamin supplementation were divided into four groups. Group A received Me-Cbl 500 microg twice/week plus FA 10 mg/day; group B received FA 10 mg/day alone; group C received no vitamin supplementation, and group D was on Me-Cbl 500 microg twice/week alone. Fasting tHcy, vitamin B12, serum (s) FA and erythrocytic (e) FA were measured predialysis before and after 4 months of therapy. RESULTS: Final tHcy levels were significantly lower in group A (10.2 +/- 3.1 micromol/l) compared to groups C (27.3 +/- 9.7 micromol/l, p < 0.001) and group D (24.3 +/- 11.8 micromol/l, p < 0.001) and similar to group B (11.2 +/- 1.9 micromol/l, p = n.s.). Mean tHcy levels showed a significant decrease in group A from 22.5 +/- 15.6 to 10.2 +/- 3.1 micromol/l (p = 0.003) and in group B from 19.9 +/- 4.0 to 11.2 +/- 1.9 micromol/l (p = 0.012), while no significant changes were observed in groups C (25.9 +/- 9.3 vs. 27.3 +/- 9.7 micromol/l, p = n.s.) and D (26.6 +/- 14.3 vs. 24.3 +/- 11.8 micromol/l, p = n.s.). CONCLUSION: Oral FA (10 mg/day) supplementation appears to be an effective approach to normalize plasma tHcy in chronic HD patients; the addition of i.v. Me-Cbl (500 microg twice/week) to this regimen showed no benefit. Separately, FA corrected hyperhomocysteinemia (HtHcy), while Me-Cbl showed no change.

The C677T thermolabile variant of methylene tetrahydrofolate reductase on homocysteine, folate and vitamin B12 in a hemodialysis center

Homocysteine is a risk factor for cardiovascular disease. Mutations in a key enzyme in homocysteine metabolism, methylenetetrahydrofolate reductase, may contribute to hyperhomocysteinemia and alter folate and cobalamin levels. After starting hemodialysis, 10 mg oral folate daily and 500 micrograms intravenous methylcobalamin once weekly were prescribed to 27 hemodialysis patients (time on hemodialysis > or = 12 months) and two groups were defined: Group A normal; Group B heterozygous. Initial, third and twelfth month measurements of homocysteine, serum folate and vitamin B12 levels were collected and analyzed. Heterozygous state of methylenetetrahydrofolate reductase prevalence was 48

. Hyperhomocysteinemia was present in both groups. Cobalamin final levels were significantly lower in Group B compared to Group A. Homocysteine, serum folate and cobalamin levels at third and twelfth month were significantly different from baseline levels but non-different between them in both groups. In Group B, vitamin B12 at third month was significantly higher than initial, but final measurements were not different from baseline determinations. In conclusion, the heterozygous prevalence of the enzyme in hemodialysis patients is similar to that reported in the general population; hyperhomocysteinemia is frequent in hemodialysis patients and final levels in heterozygous patients are significantly higher than in normal patients. Cobalamin levels are lower in the heterozygous group. After one year of treatment, homocysteine tends to increase, suggesting a secondary resistance phenomenon to vitamin supplementation in heterozygous patients.

The C677T thermolabile variant of methylene tetrahydrofolate reductase on homocysteine, folate and vitamin B12 in a hemodialysis center.

Homocysteine is a risk factor for cardiovascular disease. Mutations in a key enzyme in homocysteine metabolism, methylenetetrahydrofolate reductase, may contribute to hyperhomocysteinemia and alter folate and cobalamin levels. After starting hemodialysis, 10 mg oral folate daily and 500 micrograms intravenous methylcobalamin once weekly were prescribed to 27 hemodialysis patients (time on hemodialysis > or = 12 months) and two groups were defined: Group A normal; Group B heterozygous. Initial, third and twelfth month measurements of homocysteine, serum folate and vitamin B12 levels were collected and analyzed. Heterozygous state of methylenetetrahydrofolate reductase prevalence was 48

and homozygozity 4

. Hyperhomocysteinemia was present in both groups. Cobalamin final levels were significantly lower in Group B compared to Group A. Homocysteine, serum folate and cobalamin levels at third and twelfth month were significantly different from baseline levels but non-different between them in both groups. In Group B, vitamin B12 at third month was significantly higher than initial, but final measurements were not different from baseline determinations. In conclusion, the heterozygous prevalence of the enzyme in hemodialysis patients is similar to that reported in the general population; hyperhomocysteinemia is frequent in hemodialysis patients and final levels in heterozygous patients are significantly higher than in normal patients. Cobalamin levels are lower in the heterozygous group. After one year of treatment, homocysteine tends to increase, suggesting a secondary resistance phenomenon to vitamin supplementation in heterozygous patients.