Silver serum levels in burned patients treated with silver sulfadiazine and its toxicity on inflammatory cells.

BACKGROUND: Silver sulfadiazine (SSD) has been widely used in burned patients for the prevention of local infections. To be biologically active and exert antimicrobial properties, silver needs to be present in the form of silver ions (Ag1+) that bind to negatively charged proteins, namely, the RNA and DNA in microorganisms. However, previous published studies conducted with SSD in the 1990s reported a high level of silver absorption through damaged skin and noted the potential cytotoxicity of Ag1+ to human cells. SSD toxicity, however, had been described in cell cultures using arbitrary silver concentrations. In the present study, we determined the serum silver levels in burned patients treated with SSD and, taking into account the molar Ag1+ concentrations found in these patients, we evaluated the Ag1+ toxicity effects on inflammatory cells (ROS and cytokine production) in vitro. METHODS: Twenty patients with an average burned body surface area of 27.68% were included in this study. RESULTS: Patients' Ag1+ serum levels reached up to 558 times those of the unexposed controls. Ag1+ was then added to inflammatory cells in vitro at levels up to 2000 times the level of the control, and there was no effect on the viability of the cells nor on the rate of apoptosis. We observed a decrease in reactive oxygen species production by mononuclear (MN) and polymorphonuclear (PMN) cells, as well as a substantial decrease in cytokines IL-1ß, IL-6, IL-8, IL-10, and TNF-α production by leukocytes (MN and PNM). CONCLUSION: These findings suggest that Ag1+ may contribute to negative outcomes after burns, decreasing the primary defense mechanism (respiratory burst) and altering cytokine production.

Variabilidade na sensibilidade à heparina de reagentes do TTPA em plasmas heparinizado in vitro e de pacientes heparinizados / Variability in heparin sensitivity of TTPA reagents in heparinized plasma in vitro and patients receiving heparin

Introdução: No final da década de 80 e início dos anos 90 vários estudos demonstraram a falta de padronização e a variabilidade nos resultados do TTPA devido a diferentes sensibilidades à heparina dos reagentes empregados para sua determinação. Objetivo: Avaliar a sensibilidade à heparina de reagentes utilizados para a determinação do TTPA em amostras de plasmas heparinizadas in vitro e de pacientes em uso de heparina não fracionada (HNF). Material e Métodos: Para este estudo foi utilizado um pool de plasma heparinizado, com concentrações de 0,1 até 1,0 unidade de heparina/mL, 29 pacientes em uso de HNF e 8 kits de reagentes para a determinação do TTPA. Resultados e Discussão: Com os plasmas heparinizados in vitro os resultados com o reagente da Actin® foram estatísticamente diferente dos da Labtest®, da Human® e da Clot®. O melhor coeficiente de correlação, resultado do TTPA versus concentração de HNF, foi observado com o reagente da Stago® (R=0,9919). Quando-se empregou os plasmas de pacientes em uso de HNF os resultados do Actin® e do Actin FSL® foram estatisticamente diferentes dos da Clot®. Conclusão: Diferenças estatisticamente significativas, nos valores de TTPA, ainda são observadas, tanto em plasmas de pacientes em uso de HNF como em plasmas heparinizados in vitro de acordo com o reagente utilizado.

Introduction: At the end of the 1980s and at the beginning of the 1990s, several studies showed lack of standardization and variability in APPT results due to the different sensibilities to heparin in reagents used for its determination. Objective: To evaluate the sensibility to heparin in the different reagents used to determine APPT in samples of heparinized plasma in vitro and in patients using non-fractioned heparin (NFH). Material and Methods: This study was performed with a pool of heparinized plasma with concentrations from 0.1 to 1.0 unit heparin/mL, 29 patients using NFH and 8 reagent kits for TTPA determination. Results and Discussion: Using heparinized plasma in vitro, there was a statistically significant difference with Actin® reagent in relation to Labtest®, Human® and Clot® reagents. The best correlation coefficient, a result of the APTT versus UFH concentration was observed with reagent from Stago® (R = 0.9919). When we used the plasma from patients using UFH, the results of Actin ® and Actin FSL® were statistically different from the Clot®.

Identificação de anticorpos anti-eritrocitários de baixa frequência em paciente politransfundida com beta-talassemia: relato de caso / Identification of low frequency anti-erythrocyte antibodies in chronically transfused patient with beta-thalassemia: a case report

A taxa de aloimunização eritrocitária em pacientes politransfundidos pode atingir 50%, entretanto a frequência de anticorpos clinicamente relevantes em pacientes transfundidos não é perfeitamente conhecida, estimando-se que cerca de 1% dos pacientes são sensibilizados a cada unidade de hemácias transfundidas. O objetivo deste trabalho é relatar o caso de uma paciente de 11 anos de idade, portadora de β–talassemia major, politransfundida, na qual foi detectada, em protocolo pré-transfusional, a presença de dois anticorpos antieritrocitários raros: anti-Colton b (anti-Cob ) e anti-Lutheran 14 (anti-Lu14). Para o levantamento do histórico clínico-laboratorial da paciente, foi realizada pesquisa de prontuário arquivado no sistema de arquivos de um hospital-escola no qual a paciente é acompanhada. A fenotipagem eritrocitária em pacientes politransfudidos é essencial para minimizar os riscos de complicações devido à aloimunização e estimar a disponibilidade de sangue compatível. Assim, o relato do presente caso poderá contribuir para ampliar os conhecimentos sobre a real taxa de frequência de anticorpos anti-eritrocitários raros em paciente talassêmico.

The rate of erythrocyte alloimmunization in tranfusion-dependent patients can reach 50%, although the frequency of clinically relevant antibodies in transfused patients is not fully known, it is estimated that about 1% of patients are sensitized to each unit of transfused RBCs. The aim of this study is to report the case of an 11-year-old girl with β-thalassemia major, chronically transfused, which was detected in pre-transfusion protocol, the presence of two rare anti-erythrocyte antibodies: anti-Colton b (anti-Cob ) and anti-Lutheran 14 (anti-Lu14). To survey the clinical and laboratory patient history, research records filed in the archives of the university hospital in which the patient is monitored system was performed. The phenotyping erythrocyte in multitransfused patients is essential to decrease the risk of complications due to alloimmunization and estimate the availability of compatible blood. Thus, the report of this case may contribute to increase knowledge about of the real frequency of uncommon anti-erythrocyte antibodies in thalassemic patients.

Alterations in cell maturity and serum survival factors may modulate neutrophil numbers in sickle cell disease.

Leukocytes are known to exacerbate inflammatory and vaso-occlusive processes in sickle cell disease (SCD). The aim of this study was to determine whether alterations in neutrophil maturity and/or cell-death modulating factors in the circulation contribute to the increased leukocyte counts and leukocyte survival observed in SCD. The maturity of circulating neutrophils from healthy control individuals (CON), SCD and SCD patients on hydroxyurea therapy (SCDHU) was determined immunophenotypically. Serum factors affecting neutrophil apoptosis (determined by annexin V-binding) were analyzed by culturing control neutrophils (CON neutrophils) with pooled serum from CON, SCD and SCDHU individuals. Immunophenotypic characterization of neutrophils suggested a slight, but significant, increase in the circulation of immature neutrophils in SCD. While SCD neutrophils cultured in the presence of CON serum presented delayed apoptosis, unexpectedly, the culture of CON neutrophils with SCD serum significantly augmented apoptosis and caspase-9 activity. Inhibition of the activity of serum interleukin-8, a neutrophil-apoptosis-inhibiting cytokine, significantly increased SCD serum-induced CON neutrophil apoptosis, indicating that SCD serum may have both apoptotic and antiapoptotic properties. The decreased maturity of SCD neutrophils observed is suggestive of an accelerated immigration of leukocytes from the bone marrow to the circulating pool that may contribute to an increase in cell survival, subject to modulation by a complex balance of both anti- and proapoptotic factors contained in the circulation of SCD individuals.

Alpha-hemoglobin-stabilizing protein: an erythroid molecular chaperone.

Alpha-hemoglobin-stabilizing protein (AHSP) is an erythroid-specific protein that acts as a molecular chaperone for the free α chains of hemoglobin. Evidence strongly suggests that AHSP participates in hemoglobin synthesis and may act to neutralize the cytotoxic effects of excess free alpha-globin subunits that accumulate both in normal and beta-thalassemic erythroid precursor cells. As such, AHSP seems to be essential for normal erythropoiesis, and impaired upregulation of AHSP may lead to premature erythroid cell death, resulting in ineffective erythropoiesis. Reduced AHSP mRNA expression has been associated with clinical variability in some cases of ß-thalassemia. It has been shown that αHb variants may also impair AHSP-αHb interactions, leading to pathological conditions that resemble α-thalassemia syndromes. The aim of this paper is to summarize current information concerning the structure and function of AHSP, focusing on its role in normal erythropoiesis and its relevance in health and disease.

Aumento dos níveis de LDLox induzem maior formação de células espumosas in vitro / Increased levels of oxLDL induce higher foam cells formation in vitro

Inúmeras evidências sustentam a hipótese de que a modificação oxidativa da LDL contribui para o desenvolvimento e progressão da aterosclerose em uma variedade de modelos animais e que as células espumosas constituem um evento crucial no desenvolvimento da lesão aterosclerótica. A LDL oxidada tem uma ação quimioatraente sobre os monócitos, induzindo a transformaçãode macrófagos em células espumosas. Neste trabalho, foi desenvolvido um protocolo simples e reproduzível de cultura de células mononucleares humanas, o qual foi utilizado para avaliação da capacidade aterogênica da LDL oxidada comparada à LDL nativa naformação de células espumosas com ativação espontânea dos macrófagos. A partir do sangue de 10 indivíduos normolipidêmicos, obteve-se a LDL por processo de ultracentrifugação sendo a mesma oxidada in vitro na presença de íons cobre. Monócitos diferenciaram-se em macrófagos e foram incubados com LDL nativa e oxidada em diferentes concentrações. Houve formação decélulas espumosas apenas em macrófagos estimulados com LDL oxidada, variando quantitativamente de acordo com a sua concentração.Concluiu-se que este protocolo de estudo, além de possibilitar a utilização de macrófagos humanos, permitiu a redução do tempo de incubação da cultura. Paralelamente, demonstrou-se que a formação de células espumosas é dependente da extensão do grau deoxidação da LDL

Much evidence sustains the hypothesis that oxidative modification of low-density lipoprotein (LDL) contributes to the development and progression of atherosclerosis and that foam cells constitute a crucial event in the development of the atheroscleroticlesion. Oxidized LDL (oxLDL) presents a chemotatic action on monocytes, inducing the transformation of macrophages into foam cells. In this work, a simple reproducible protocol for culturing human mononuclear cells was developed to evaluate the atherogeniccapacity of oxLDL compared to native LDL in the formation of foam cells. Monocytes differentiate into macrophages when stimulatedwith native and oxidized LDL at different concentrations. Foam cell formation only occurred in macrophages stimulated by oxLDL, which varied quantitatively according to its concentration. This study protocol, besides making the use of human macrophages possible, permitted a reduction in culture incubation time. Moreover, the study demonstrated that foam cell formation is dependent on the degree of LDL oxidation

Efeitos do ramipril, captopril e sinvastatina na injúria da preservação a frio de rins de ratos / Effects of ramipril, captopril, and simvastatin on cold-storage damage in rat kidneys

Introdução: A preservação a frio geralmente é utilizada para minimizar a injúria renal durante a preservação. Testamos se a adição de sinvastatina, captopril, e ramipril à solução de Euro-Collins (EC) ou o pré-tratamento de rins de ratos doadores com ramipril e/ou sinvastatina poderia reduzir a injúria da preservação renal. Métodos: Inicialmente, adicionamos ramipril e sinvastatina à solução de EC, contendo fragmentos de rins de ratos que foram preservados a frio por 24 horas (n=6). O dano tecidual foi avaliado pela liberação de desidrogenase lática (DHL). In vivo, ramipril, por gavagem, e/ou sinvastatina, intraperitonealmente, foram administrados aos ratos doadores 18h antes da nefrectomia.Fragmentos renais foram estocados a frio em EC durante 24h ou 48h. O dano tecidual foi avaliado, utilizando a liberação de DHL, substâncias reativas ao ácido tiobarbitúrico (TBARS), teste do MTT e pelo exame morfológico após 0, 24, e 48h (n=10). Concomitantemente, captopril foi acrescentado à solução de EC e fragmentos adicionais dos rins de ratos controles foram estocados a frio durante 24h e 48h, com dano tecidual avaliado por liberação de DHL e exame histológico. Resultados: A adição de ramipril e sinvastatina à solução de EC não afetou a viabilidade dos fragmentos renais (p>0,05). A adução de captopril na solução de EC também não melhorou a viabilidade durante a preservação a frio, avaliada pela liberação de desidrogenase lática e pelo escore histológico (p>0,05). O pré-tratamento dos doadores renais com ramipril e/ou sinvastatina não alterou significativamente o MTT, MDA, DHL ou escores histológicos. Discussão: Inibidores da ECA e estatinas protegem contra a injúria da isquemia-reperfusão (I/R) após pré-tratamento por alguns dias e reduzem o estresse oxidativo e marcadores inflamatórios e poderiam melhorar a capacidade antioxidante da solução de EC...

Background: Cold storage is generally used to minimize kidney injury during preservation. We tested whether or not addition of simvastatin, captopril, and ramipril in the Euro-Collins solution (EC) or pre-treatment of rat kidney donors with ramipril and/or simvastatin reduced preserved kidney injury.Methods: We first added ramipril and simvastatin to EC with rat kidney fragments that were cold-stored for 24 hours (n=6). Tissue damage was assessed by lactate dehydrogenase (LDH). In vivo, ramipril, by gavage, and/or intraperitoneal simvastatin , were administered to donor rats 18h before nephrectomy. Kidney fragments were cold-stored in EC for 24h or 48h. Tissue damage was assessed by LDH release, TBARS, MTT-assay, and by morphologic assessment at 0, 24, and 48h (n=10). Concomitantly, captopril was added to EC and additional fragments of control rat kidneys were coldstored for 24 and 48h, with damage assessed by LDH release and histology. Results: The addition of ramipril and simvastatin to EC solution did not change the viability of rat kidney fragments (p>0.05). The addition of captopril in the EC solution also did not improve cold-storage viability, as assessed by LDH release levels and histological scores (p>0.05). Pre-treatment of kidney donors with ramipril and/or simvastatin did not significantly change MTT, MDA, LDH levels or histological scores.Discussion: ACEIs and statins protect against organ I/R injury after donor pre-treatment for a few days and reduce oxidant stress and inflammatory markers, and could improve the antioxidant capacity of EC solution. In the tested concentrations, inclusion of captopril, ramipril, and simvastatin in the EC solution did not improve the preservation quality of cold-stored rat kidney fragments...

[Crohn's disease and kidney stones: much more than coincidence?]. / Doença de Crohn e cálculo renal: muito mais que coincidência?

BACKGROUND: Crohn's disease is an inflammatory bowel disease associated with a wide variety of complications and manifestations secondary to the effects of underlie inflammatory process. In about 30% of the patients with Crohn's disease can be found extra-intestinals symptoms. Nephrolithiasis is one of them and the appearance of kidney stones, mainly of oxalate of calcium, is more common in these patients than in general population. AIM: To evaluate urinary metabolic factors potentially involved in renal stones formation on patients with Crohn's disease. METHODS: We evaluated 29 patients with Crohn's disease followed in the Outpatient Bowel Inflammatory Disease Clinics of State University Hospital, Londrina, PR, Brazil, from January to December of 2004. The metabolic evaluation included measured of blood and urine substances related to renal stones formation, kidneys, ureters and bladder ultrasonography and calculation of urinary supersaturation for calcium oxalate, uric acid and calcium phosphate. RESULTS: Twenty-nine of the evaluated patients were female or 65.5% and 34.5% were males. Among the metabolic urinary studied, we identified the following potential disturbances associated with nephrolithiasis: hypocitraturia in 21 patients (72.4%), hypomagnesuria in 12 (41.4%), hyperoxaluria in 4 (13.6%) and urinary volume low in 5 (17.2%). Renal stones were identified in 13 patients (44.8%). Oxalate urinary excretion was higher in patients submitted to bowel surgery and also in patients with ileum resection. The urinary supersaturation of calcium oxalate and brushita in patients with bowels surgery was higher than the other patients not submitted to any surgery. Data to compare patients who underwent to surgery or not were analyzed by Mann-Whitney test (U test), and Qui-square test or the accurate test of Fisher have been used to determine variables association. For all tests 5% of significance level was considered. CONCLUSION: This study shows that the frequency of renal stones in patients suffering from Crohns disease is higher than in general population and, also, higher than that described elsewhere for this disease. We identified hypocitraturia and hypomagnesiuria as the main factors which could explain our data. The impact of these metabolic disturbances can be also evaluated by means of the high supersaturation obtained for calcium oxalate and calcium phosphate which suggests the way those factors could be influencing crystal nucleation and, consequently, lead to renal stones formation in this group of patients.

Doença de Crohn e cálculo renal: muito mais que coincidência? / Crohn’s disease and kidney stones: much more than coincidence?

RACIONAL: A doença de Crohn é uma doença inflamatória intestinal que pode estar associada a várias complicações e manifestações que são secundárias ao processo inflamatório de base. Em aproximadamente 30 por cento dos pacientes têm sido encontradas manifestações extra-intestinais. A nefrolitíase é uma delas e a formação de cálculos é mais comum nestes pacientes do que na população em geral, principalmente cálculos de oxalato de cálcio. OBJETIVOS: Avaliar os fatores metabólicos urinários potencialmente envolvidos na formação de cálculos renais em pacientes com doença de Crohn. MÉTODOS: Foram avaliados 29 pacientes com doença de Crohn atendidos no Ambulatório de Doenças Inflamatórias do Hospital de Clínicas da Universidade Estadual de Londrina, PR, no período de janeiro a dezembro de 2004. A avaliação metabólica incluiu medidas séricas e urinárias de substâncias relacionadas à litíase renal, ultra-sonografia de rins e vias urinárias e cálculo da supersaturação urinária para o oxalato de cálcio, ácido úrico e fosfato de cálcio. RESULTADOS: Dos 29 pacientes avaliados, 65,5 por cento eram do sexo feminino e 34,5 por cento do masculino. As principais alterações metabólicas urinárias encontradas foram 72,41 por cento de hipocitratúria, 41,4 por cento de hipomagnesiúria, 13,6 por cento de hiperoxalúria e 17,24 por cento de baixo volume urinário. Foram encontrados cálculos renais em 13 pacientes (44,8 por cento). Os pacientes submetidos a cirurgia intestinal, com ressecção ileal, apresentaram alterações na saturação urinária de oxalato e fosfato. Para a comparação das médias, utilizou-se o teste de Mann-Whitney e para determinar a associação entre as variáveis foi utilizado o teste do Qui-quadrado ou o teste exato de Fisher com um nível de significância de 5 por cento. CONCLUSÃO: A freqüência de pacientes com cálculos renais foi maior que a encontrada na população geral e acima do descrito em trabalhos similares. As alterações encontradas como...

BACKGROUND: Crohn’s disease is an inflammatory bowel disease associated with a wide variety of complications and manifestations secondary to the effects of underlie inflammatory process. In about 30 percent of the patients with Crohn’s disease can be found extra-intestinals symptoms. Nephrolithiasis is one of them and the appearance of kidney stones, mainly of oxalate of calcium, is more common in these patients than in general population. AIM: To evaluate urinary metabolic factors potentially involved in renal stones formation on patients with Crohn’s disease. METHODS: We evaluated 29 patients with Crohn’s disease followed in the Outpatient Bowel Inflammatory Disease Clinics of State University Hospital, Londrina, PR, Brazil, from January to December of 2004. The metabolic evaluation included measured of blood and urine substances related to renal stones formation, kidneys, ureters and bladder ultrassonography and calculation of urinary supersaturation for calcium oxalate, uric acid and calcium phosphate. RESULTS: Twenty-nine of the evaluated patients were female or 65.5 percent and 34.5 percent were males. Among the metabolic urinary studied, we identified the following potential disturbances associated with nephrolithiasis: hypocitraturia in 21 patients (72.4 percent), hypomagnesuria in 12 (41.4 percent), hyperoxaluria in 4 (13.6 percent) and urinary volume low in 5 (17.2 percent). Renal stones were identified in 13 patients (44.8 percent). Oxalate urinary excretion was higher in patients submitted to bowel surgery and also in patients with ileum resection. The urinary supersaturation of calcium oxalate and brushita in patients with bowels surgery was higher than the other patients not submitted to any surgery. Data to compare patients who underwent to surgery or not were analyzed by Mann-Whitney test (U test), and Qui-square test or the accurate test of Fisher have been used to determine variables association. For all tests 5 percent...

Diabetes mellitus induzido por estreptozotocina: comparaçäo em longo prazo entre duas vias de administraçäo / Streptozotocin-induced diabetes mellitus: long-term comparison of two drug administration routes

O objetivo é avaliar em longo prazo, em ratos, a severidade e a duraçäo do diabetes mellitus induzido pela administraçäo de estreptozotocina (STZ) intraperitoneal e por dois sítios endovenosos (sublingual e caudal). Foram estudados quatro grupo de 10 ratos Wistar-Furth isogênicos. Um grupo de animais näo recebeu STZ (controle). STZ mg/kg foi injetada no peritônio, na veia sublingual e na veia da cauda, para a formaçäo dos outros três grupos de estudo. Pesos e glicemias foram documentados no dia da injeçäo da droga e em uma, duas, seis, oito, 20, 30 e 40 semanas após. Näo houve aparecimento de diabetes espontâneo no grupo-controle. Independentemente da via utilizada para administrtaçäo, a severidade e a duraçäo do diabetes induzido pela STZ foram semelhantes entre os grupos de estudo. Houve, no entanto, 30 porcento de falha da STZ quando ela foi dada intraperitonealmente; 10 porcento dos animais que receberam STZ em uma veia caudal e 30 porcento dos que a receberam em uma veia sublingual morreram precocemente por toxicidade. Na dose escolhida, e por qualquer uma das vias utilizadas, STZ promoveu diabetes mellitus severo e de longa duraçäo. Para alcançar a dose diabetogênica, sua injeçäo em uma das veias da cauda mostrou-se a mais conveniente.(au)