Tuberculosis pleural en un hospital del Noreste Argentino / Pleural tuberculosis in a hospital in Northeast Argentina

La tuberculosis (TB) pleural ocupa el primer lugar dentro de las localizaciones extrapulmonares. El objetivo de este trabajo fue estimar la proporción de TB pleural entre los casos de TB y caracterizar la forma de presentación, métodos de diagnóstico y evolución de los pacientes internados en el Servicio de Clínica Médica del hospital Ángela I. de Llano, Corrientes, Argentina, durante el período enero de 2011 a junio de 2014. Se realizó un estudio observacional y descriptivo. Fueron diagnosticados 10 pacientes con TB pleural. La edad media fue 48.5 ± 16.9 (16-63) años. El tiempo de evolución antes de la consulta fue 21.3 ± 11.6 (7-45) días. Todos fueron exudados unilaterales, con recuento celular de 2152 ± 687 (84-7000) células; 8 casos presentaron predominio linfocitario. El valor promedio de adenosina deaminasa (ADA) fue 92.7 ± 27.0 (60-150) UI/l. La baciloscopia del líquido pleural fue positiva en 4 casos; se obtuvo desarrollo de Mycobacterium tuberculosis en 3 casos. En el estudio histológico 3 presentaron granulomas caseificantes. Se registró un óbito. Si bien suele darse en hombres, de mediana edad, con un tiempo de evolución menor al mes, como un derrame pleural unilateral exudativo a predominio de linfocitos, el diagnóstico de certeza presenta sus limitaciones, por ende la clínica, la epidemiología, los estudios por imágenes, la anatomía patológica y los exámenes de laboratorio, como la determinación de los niveles de ADA, constituyen un aporte valioso para el diagnóstico.

Pleural tuberculosis ranks first in extrapulmonary sites. The aim of this study was to estimate the proportion pleural TB among TB cases, and characterize the presentation, diagnostic methods and outcomes of patients hospitalized in the Ángela I. de Llano hospital, Corrientes, Argentina, between January 1, 2011 and June 30, 2014. We performed a descriptive and observational study. Ten patients were diagnosed with TB pleural effusion. The mean age was 48.5 ± 16.9 (16-63) years. The average evolution time before the consultation was 21.3 ± 11.6 (7-45) days. All were unilateral, exudates, with cell count of 2152 ± 687 (84-7000) cells; 8 cases had lymphocyte predominance. The average value of adenosine deaminase determination (ADA) was 92.7 ± 27.0 (60-150) IU/l. The pleural effusion smear was positive in 4 cases; development of Mycobacterium tuberculosis was obtained in 3 cases; histologically, three presented caseating granulomas. One death was recorded. Although pleural TB usually occurs in male patients, middle-aged, as a unilateral exudative pleural effusion with lymphocytic predominance, with less than a month´s evolution, diagnostic certainty has its limitations, thus clinical suspicion, epidemiology, imaging, pathology and laboratory tests, and determination of adenosine deaminase levels, represent a valuable contribution to diagnosis.

ADENOSINE DEAMINASE ACTIVITY AND SERUM C-REACTIVE PROTEIN AS PROGNOSTIC MARKERS OF CHAGAS DISEASE SEVERITY / Atividade da adenosina deaminase e níveis de proteina C reativa sérica como marcadores de gravidade na doença de Chagas

SUMMARY Chagas disease is a public health problem worldwide. The availability of diagnostic tools to predict the development of chronic Chagas cardiomyopathy is crucial to reduce morbidity and mortality. Here we analyze the prognostic value of adenosine deaminase serum activity (ADA) and C-reactive protein serum levels (CRP) in chagasic individuals. One hundred and ten individuals, 28 healthy and 82 chagasic patients were divided according to disease severity in phase I (n = 35), II (n = 29), and III (n = 18). A complete medical history, 12-lead electrocardiogram, chest X-ray, and M-mode echocardiogram were performed on each individual. Diagnosis of Chagas disease was confirmed by ELISA and MABA using recombinant antigens; ADA was determined spectrophotometrically and CRP by ELISA. The results have shown that CRP and ADA increased linearly in relation to disease phase, CRP being significantly higher in phase III and ADA at all phases. Also, CRP and ADA were positively correlated with echocardiographic parameters of cardiac remodeling and with electrocardiographic abnormalities, and negatively with ejection fraction. CRP and ADA were higher in patients with cardiothoracic index ≥ 50%, while ADA was higher in patients with ventricular repolarization disturbances. Finally, CRP was positively correlated with ADA. In conclusion, ADA and CRP are prognostic markers of cardiac dysfunction and remodeling in Chagas disease.

Introdução e objetivo . A Doença de Chagas é um problema de saúde pública mundial. A disponibilidade de ferramentas diagnósticas para prever o desenvolvimento de miocardiopatia chagásica crônica é fundamental para reduzir a morbidade e a mortalidade. Aqui estudamos o valor prognóstico da atividade sérica da adenosina deaminase (ADA) e dos níveis de proteína C reativa (PCR) em indivíduos chagásicos. Métodos : 110 indivíduos: 28 saudáveis e 82 pacientes chagásicos foram divididos de acordo com a gravidade da doença em fase I (n = 35), II (n = 29) e III (n = 18). Para cada indivíduo foram feitos uma história médica, eletrocardiograma, radiografia de tórax e ecocardiografía transtorácica. O diagnóstico de Chagas foi confirmado por ELISA e MABA utilizando antígenos recombinantes, a atividade sérica da enzima ADA foi determinada por espectrofotometria, e os níveis séricos de PCR por ELISA. Resultados : os níveis de PCR e da atividade da ADA aumentaram linearmente em relação à fase da doença, sendo a PCR significativamente maior na fase III, e a ADA em todas as fases. Além disso, PCR e ADA foram correlacionados positivamente com parâmetros ecocardiográficos de remodelamento cardíaco e alterações eletrocardiográficas, e negativamente com a fração de ejeção. PCR e ADA foram mais elevadas em pacientes com índice cardiotorácico ≥ 50%, enquanto que a ADA foi maior em pacientes com alterações da repolarização ventricular. Finalmente, os níveis de PCR foram correlacionados positivamente com a atividade da ADA. Conclusão : ADA e PCR são marcadores prognósticos de disfunção e remodelamento cardíaco na Doença de Chagas, e devem ser incluídos na avaliação e acompanhamento dos pacientes.

Adenosin deaminasa en la tripanosomiasis experimental: futuras implicaciones / Adenosine deaminase in experimental trypanosomiasis: future implications

La adenosin deaminasa representa un punto de control en la regulación de los niveles extracelulares de adenosina, desempeñando así un papel fundamental en la modulación de las respuestas purinérgicas a ciertos eventos patofisiológicos. Diversos estudios señalan que los niveles séricos y plasmáticos de la enzima se elevan en algunas enfermedades causadas por microorganismos, lo cual podría representar un mecanismo compensatorio como consecuencia de la elevación de las concentraciones de adenosina y la liberación de mediadores inflamatorios. Recientes investigaciones indican que la actividad de la adenosin deaminasa disminuye e influye en los parámetros hematológicos de animales infectados con Trypanosoma evansi, de manera que tales alteraciones podrían tener implicaciones en la patogénesis de la enfermedad. Adicionalmente, la enzima ha sido detectada en este parásito; lo que permite inferir que podría estar asociada a las funciones vitales del mismo, de manera similar a lo que ocurre en los mamíferos. Este conocimiento puede ser útil al asociar la quimioterapia con inhibidores específicos de la enzima en futuros estudios.

The adenosine deaminase represents a control point in the regulation of extracellular adenosine levels, thus playing a critical role in the modulation of purinergic responses to certain pathophysiological events. Several studies have shown that serum and plasma enzyme levels are elevated in some diseases caused by microorganisms, which may represent a compensatory mechanism due to the elevated levels of adenosine and the release of inflammatory mediators. Recent research indicates that adenosine deaminase activity decreases and affects hematological parameters of infected animals with Trypanosoma evansi, so that such alterations could have implications in the pathogenesis of the disease. In addition, the enzyme has been detected in this parasite; allowing the inference that it could be associated with the vital functions of the same, similar to what occurs in mammals. This knowledge may be useful in the association of chemotherapy with specific inhibitors of the enzyme in future studies.

Effect of Zinc Supplementation on Adenosine Deaminase Activity in Leprosy.

Serum Adenosine Deaminase (ADA) acts as marker of cellular immunity and its activity is found to be altered in various diseases in which there is a cell mediated immune response (CMI) including leprosy. The role of zinc is well established in the development and maintainence of immunocompetence and its supplementation activates the immune response in particular Tlymphocytes and monocytes in several ways. The aim of the study was planned to evaluate the effect of nutritional zinc supplementation on cell mediated immune response by investigating the pre and post intervention serum ADA levels after oral zinc sulphate supplementation in leprosy patients. A total of 49 cases, 30 Tuberculoid Leprosy (TT) and 19 Lepromatous Leprosy (LL) patients, within the age group of 25-60 years were enrolled in the study along with 30 age matched healthy controls. Serum ADA was estimated in all the subjects before and after (2 months and 4 months) oral zinc supplementation. Pre intervention serum ADA level was observed to be significantly increased in both the TT and LL (p<0.001) groups as compared to controls, revealing raised immunological activity in the patients. After oral zinc sulphate supplementation serum ADA re-evaluation was done in 38 cases. A highly significant (p < 0.001 ) rise in ADA level was registered in the post intervention period (4 months supplementation) in TT cases with a moderately significant (p< 0.05) increase in LL cases, indicating the ability of oral zinc therapy to affectively alter the cell mediated immune response in leprosy.

Serum adenosine deaminase, catalase and carbonic anhydrase activities in patients with bladder cancer

OBJECTIVES: The relationship between adenosine deaminase and various cancers has been investigated in several studies. However, serum adenosine deaminase activity and carbonic anhydrase and catalase activities in patients with bladder cancer have not previously been reported. Therefore, the aim of this study was to measure serum adenosine deaminase, carbonic anhydrase and catalase activities in patients with bladder cancer. MATERIALS AND METHODS: Forty patients with bladder cancer and 30 healthy controls were enrolled in the study. Serum adenosine deaminase, carbonic anhydrase and catalase activities were measured spectrophotometrically. RESULTS: Serum adenosine deaminase, carbonic anhydrase and catalase activities were significantly higher in patients with bladder cancer than controls (all significant, p<0.001). CONCLUSIONS: These markers might be a potentially important finding as an additional diagnostic biochemical tool for bladder cancer.

Adenosin deaminasa como molécula coestimuladora y marcador de inmunidad celular / Adenosine deaminase as costimulatory molecule and marker of cellular immunity

La adenosin deaminasa (ADA), es una enzima del metabolismo de las purinas que ha sido objeto de mucho interés debido a que el defecto congénito de esta enzima causa el síndrome de inmunodeficiencia combinada severa. Una de las tres isoformas de la enzima (ecto-ADA) es capaz de unirse a la glicoproteína CD26 y a los receptores de adenosina A1 y A2B. La interacción ADA-CD26 produce una señal coestimuladora en los eventos de activación de las células T y en la secreción de IFN-g, TNF-a e IL-6. Durante dicha activación la actividad de la enzima está regulada de manera positiva por IL-2 e IL-12 y negativamente por IL-4, basado en un mecanismo de translocación. Diversos estudios señalan que los niveles séricos y plasmáticos de ADA se elevan en algunas enfermedades causadas por microorganismos que infectan principalmente a los macrófagos; así como en trastornos hipertensivos, lo cual podría representar un mecanismo compensatorio como consecuencia de la elevación de los niveles de adenosina y la liberación de mediadores hormonales e inflamatorios estimulados por la hipoxia.

Adenosine deaminase (ADA) is an enzyme of purine metabolism which has been the subject of much interest because the congenital defect of this enzyme causes severe combined immunodeficiency syndrome. One of the three isoforms of the enzyme (ecto-ADA) is capable of binding to the glycoprotein CD26 and adenosine receptors A1 and A2B. ADA-CD26 interaction produces a costimulatory signal in the events of T cell activation and secretion of IFN-g, TNF-a and IL-6. During this activation, the enzyme activity is regulated positively by IL-2 and IL-12 and negatively by IL-4, based on the mechanism of translocation. Diverse studies suggest that seric and plasmatic levels of ADA rise in some diseases caused by microorganisms infecting mainly the macrophages and in hypertensive disorders, which may represent a compensatory mechanism resulting from increased adenosine levels and the release of hormones and inflammatory mediators estimulated by hipoxia.

Determination of serum adenosine deaminase and xanthine oxidase levels in patients with crimean-congo hemorrhagic fever

OBJECTIVE: Crimean-Congo hemorrhagic fever is an acute viral hemorrhagic fever with a high mortality rate. Despite increasing knowledge about hemorrhagic fever viruses, little is known about the pathogenesis of Crimean-Congo hemorrhagic fever. In this study, we measured serum adenosine deaminase and xanthine oxidase levels in Crimean-Congo hemorrhagic fever patients. METHODS: Serum adenosine deaminase levels were measured with a sensitive colorimetric method described by Giusti and xanthine oxidase levels by the method of Worthington in 30 consecutive hospitalized patients (mean age 42.6 ± 21.0). Laboratory tests confirmed their diagnoses of Crimean-Congo hemorrhagic fever. Thirty-five subjects (mean age 42.9 ± 19.1) served as the control group. RESULTS: There was a significant difference in adenosine deaminase and xanthine oxidase levels between cases and controls (p<0.05). However, neither adenosine deaminase nor xanthine oxidase levels varied with the severity of disease in the cases assessed (p>0.05). CONCLUSION: Adenosine deaminase and xanthine oxidase levels were increased in patients with Crimean-Congo hemorrhagic fever. Elevated serum xanthine oxidase activity in patients with Crimean-Congo hemorrhagic fever may be associated with reactive oxygen species generated by the xanthine/xanthine oxidase system during inflammatory responses. In addition, elevated lipid peroxidation may contribute to cell damage and hemorrhage. The association of cell damage and hemorrhage with xanthine oxidase activity should be further investigated in large-scale studies.

Los niveles séricos de adenosin deaminasa y ácido úrico se correlacionan en pacientes gestantes con trastornos hipertensivos / Serum levels correlations of the enzyme adenosine deaminase (ADA) and uric acid in pregnant with hypertensive disorders

Objetivo: Evaluar los niveles séricos de la enzima adenosin-deaminasa (ADA) en pacientes gestantes normales y en pacientes con trastornos hipertensivos del embarazo, para determinar su relación con la gravedad del trastorno hipertensivo y con los niveles séricos de marcadores bioquímicos. Método: Se evaluaron pacientes con preeclampsia leve, preeclampsia grave, hipertensión gestacional y embarazadas sanas (n=10 por cada grupo). Se determinaron los niveles de ADA, ácido úrico, creatinina, amonio y enzimas hepáticas. Resultados: Se detectó una elevación en los niveles séricos de ADA en pacientes con preeclampsia y con hipertensión gestacional, en comparación con aquellas que cursaron con un embarazo normal. Los niveles ADA se correlacionaron positivamente con los niveles de ácido úrico y creatinina, más no con la severidad clínica. A su vez los niveles de ácido úrico se asociaron con la creatinina sérica y con la severidad clínica de los trastornos hipertensivos. Se encontró un incremento en los niveles de amonio en los pacientes con preeclampsia, el cual no se correlacionó con los otros marcadores bioquímicos, mientras que los niveles de TGO, TGP y LDH se encontraron significativamente elevados en la preeclampsia grave. Conclusión: Este estudio permite relacionar la actividad de ADA con los trastornos hipertensivos del embarazo, los niveles elevados de amonio con la preeclampsia y los niveles de ácido úrico, TGO, TGP y LDH con la severidad de los trastornos hipertensivos.

Objective: To evaluate serum levels of the enzyme adenosine deaminase (ADA) in normal pregnant and patients with hypertensive disorders induced by pregnancy, in order to determine their relationship with the severity of the hypertensive disorder and with serum biochemical markers. Method: We evaluated patients with mild preeclampsia, severe preeclampsia, gestational hypertension and healthy pregnancy (n=10 per group). We determined the serum levels of ADA, uric acid, creatinine, ammonia and liver enzymes. Results: In patients with preeclampsia and gestational hypertension we detected a rise in serum ADA as compared with those who had undergone a normal pregnancy. ADA levels were positively correlated with uric acid and creatinine serum levels, but not with clinical severity. Uric acid levels were associated with serum creatinine and the clinical severity of hypertensive disorders. We also found an increase in ammonia levels in patients with preeclampsia, which did not correlate with other biochemical markers, while the levels of SGOT, SGPT, and LDH were significantly elevated in severe preeclampsia. Conclusion: This study establishes a link between the activity of ADA with hypertensive disorders of pregnancy, high levels of ammonium with preeclampsia and uric acid, SGOT, SGPT and LDH levels with the severity of hypertensive disorders.

[Comparison of adenosine deaminase serum level in COPD patients and healthy subjects]

Global initiative for Chronic Obstructive Pulmonary Disease [Gold] has defined COPD as a disease characterized by airflow limitation that is not fully reversible. COPD is a subset of obstructive lung diseases which also includes cystic fibrosis, bronchitis and asthma. Adenosine deaminase [ADA, E.C.3.5.4.4] converts adenosine to inosine. ADA has two isoenzymes; ADA1 and ADA2. In COPD patients the serum level of ADA increases which can be regarded as a result of reduction in ADA activity. In this study we evaluated the level of ADA and its isoenzymes in COPD patients and healthy subjects. This was a case control study. ADA activity in 30 COPD patients with age range of 20-60 years whose disease had been confirmed by a pulmonologist in Ekbatan Hospital, was compared to the activity of the same enzyme in 60 healthy subjects consisting of 30 non smoker and 30 smoker subjects as control groups. Data were introduced into SPSS version.13 software and analyzed by Kruskall-Wallis and two-way ANOVA tests. ADA activity in the COPD and smoker control groups was significantly lower than that of non smoker group [18.99 +/- 7 and 22.99 +/- 6.7 U/L, respectively]. Regarding ADA2 serum level, the difference between patient group and non smoker control group was significant [P<0.05]. Activity of ADA1 isoenzyme in the study groups did not show any significant differences. In general ADA activity was decreased in COPD patients. Decreased ADA activity together with increased adenosine level may play an important role in producing pulmonary damage in COPD patients

Diagnostic value of adenosine deaminase to differentiate exudates and transudates.

The differentiation of pleural effusions as exudates or transudates is the first step in the diagnosis of pleural effusions. The aim of this study was to evaluate the value of adenosine deaminase (ADA) concentration in the pleural effusions for differentiating exudates from transudates. Sixty indoor patients, admitted to our hospital, having pleural effusions and suffering from varying etiologies were included in this study. According to the final diagnosis, these 60 patients were divided into two groups: exudates (50) and transudates (10). The mean pleural ADA, serum ADA and pleural fluid/serum ADA ratio were significantly (P < 0.0001) higher in exudates as compared to transudates. Using a cut-off point of 22 IU/L, the sensitivity and specificity of pleural ADA in the diagnosis of exudates was computed to be 90% and 90% respectively. At a cut-off point 1.28, pleural fluid/serum ADA ratio was found to have sensitivity 84% and specificity 90%, respectively. From this study it is concluded that, ADA is a useful biochemical marker to suggest exudative effusions.

Changes in Serum Adenosine Deaminase Activity during Normal Pregnancy

Adenosine deaminase (ADA), an enzyme essential for the differentiation of lymphoid cells, has been used for monitoring diseases with altered immunity. The purpose of this study was to investigate the changes in serum ADA activity throughout normal pregnancy. We measured the catalytic values of serum ADA from 202 normal pregnant women using a commercial kit. Subjects were divided into four groups according to the gestational age in weeks (Gwks) (Group I: 5-9 Gwks [n=58]; Group II: 15-20 Gwks [n= 63]; Group III: 24-30 Gwks [n=34]; Group IV: 30-39 Gwks [n=47]). The serum ADA levels for the Groups I, II, III, and IV were as follows: 20.1+/-6.9 IU/L, 20.0+/-7.6 IU/L, 37.9+/-19.9 IU/L, and 24.5+/-8.6 IU/L, respectively. The serum ADA activity of group III was significantly higher than the other groups (p<0.05). However, there was no significant correlation between the Gwks and the serum ADA activity. Furthermore, other parameters, such as maternal age (p=0.29), gestational age at delivery (p=0.07), delivery mode (p=0.39), and birth weight (p=0.59) had no correlation with ADA activity. Reference values of serum ADA in normal pregnancy may provide important database for making clinical decisions in pregnancies complicated by conditions where cellular immunity has been altered.

Evaluation of adenosine deaminase seric activity in the diagnosis of bovine tuberculosis

Determination of seric levels of adenosine deaminase (ADA), an enzyme produced by monocytes/macrophages and lymphocytes, has been used in the diagnosis of human tuberculosis (TB). In the present study, ADA seric activity was evaluated comparatively to the comparative tuberculin test in the diagnosis of bovine tuberculosis. Two hundred fifty-six cattle were classified by origin and by the comparative tuberculin test as TB-positive animals (n = 52, from herds where the Mycobacterium bovis had previously been isolated), and TB-negative animals (n = 204, TB-free herds). The mean ADA seric value from the TB-positive group (4.45 ± 2.33 U/L) was significantly lower (p = 0.008) than that observed in sera from the TB-negative group (6.12 ± 4.47 U/L). When animals from a herd with clinical cases of enzootic bovine leukosis of TB-negative group were withdrawn from analysis, the mean ADA seric values of TB-negative group (5.12 ± 3.75 U/L) was not significantly different anymore from that of the TB-positive group (p = 0.28). There was no agreement in the diagnosis of bovine TB between comparative tuberculin test and determination of ADA seric values, using two different cutoff points, being 6.12 U/L and 15.0 U/L, (kappa = -0.086 and kappa = -0.082, respectively). In conclusion, the determination of ADA seric activity was not a good auxiliary test for bovine TB, because it was not able to distinguish between TB-positive and TB-negative animals.

relationship between serum total sialic acid levels and adenosine deaminase activity in obesity

To evaluate the relationship between serum adenosine deaminase [AD] activity and serum total sialic acid [TSA] levels in obese individuals. We performed this study at the Department of Chemistry, Division Biochemistry, Kahramanmaras Sutcu Imam University Arts and Science Faculty, Turkey from 2003 to 2004. Fifty obese subjects and 25 non-obese healthy controls were included in the study. The serum AD activity and TSA concentrations were measured by spectrophotometric methods. The AD activity [p<0.01] and TSA concentrations [p<0.001] were significantly higher in the sera of obese subjects than those of non-obese control subjects. But, there was no statistically significant difference in the serum TSA levels and AD activity of the obese subjects with metabolic syndrome properties compared with those without metabolic syndrome properties. A significant correlation between the serum TSA and AD was found in the obese subjects [p<0.05, r: 0.33]. Our findings suggest that there may be a closer interaction between the inflammatory events and obesity. However, our observations need to be confirmed by further studies to understand more regarding the underlying mechanisms

Effect of L-carnitine supplementation on growth and immunological status of children with chronic renal failure on regular hemodialysis

Children with chronic renal failure, including those on hemodialysis are most commonly presented with growth failure and immunological disorders. Deficiency of L-Carnitine, the endogenous intermediate involved in fatty acid metabolism, is commonly encountered in patients with end stage renal disease [ESRD]. This study has been conducted to evaluate the effect of L-Carnitine supplementation on growth and immunological status of children with ESRD. The study was conducted on twenty children with ESRD on regular hemodialysis for 1-6 years. Twelve age and sex matched healthy children were chosen to represent the control group. The growth status was monitored by the routine anthropometric measurements as well as measuring serum levels of insulin-like growth factor-1 [IGF-1]. The immunological status was monitored by measuring serum levels of adenosine deaminase [ADA] enzyme activity as well as serum levels of immunoglobulins G and M [IgG and IgM]. L-Carnitine supplementation was given to all patients in a dose of 50 mg/kg/day orally for 6-months. Basal and post 6-months L-Carnitine supplementation levels of IGF-1, ADA, IgG and IgM were compared to values of healthy controls. L-Carnitine supplementation improves IGF-1 level. Where basal values were significantly lower than those of control while post supplementation values showed insignificant difference when compared to control group. Although ADA activity significantly increased in ESRD patients after L-Carnitine supplementation in comparison to their corresponding basal values, both values were significantly lower when compared to control group. L-Carnitine supplementation had no significant effect on serum levels of IgG and IgM which showed insignificant difference when compared to control group. L-Carnitine supplementation plays an important role in improving both growth and immunological disorders in children with chronic renal failure and it should be considered an intergeral therapy for children on regular hemodialysis

Characterization of adenosine deaminase (ADA) in Hemolymph of Biomphalaria glabrata

A adenosina é uma molécula sinalizadora de muitos eventos celulares. A adenosina desaminase (ADA) é enzima chave para o controle dos níveis intra e extra celulares de adenosina. A atividade da ADA foi detectada em hemolinfa de B. glabrata e suas condições ótimas de ensaio foram determinadas experimentalmente. A variação do pH de 6,2 até 7,8 não causou mudança significativa na atividade. O Km aparente foi de 734 µmoles L-1, usando adenosina como substrato. A maior atividade foi encontrada usando 37ºC como temperatura de incubação. As condições de ensaio padrão foram então estabelecidas como sendo 15 minutos de tempo de incubação, 0,4 µL de hemolinfa por ensaio, pH 6.8 e 37ºC de temperatura de incubação. A enzima apresentou atividades de 834 ± 67 µmols.min-1.L-1 (25ºC) e 2029 ± 74 µmols.min-1.L-1 (37ºC), em torno de 40 e 100 vezes maiores que os níveis encontrados em soro de humanos sadios. Em temperaturas superiores, essa atividade cai 20% a 43ºC e 70% a 50ºC, em 15 minutos. A ADA perde 26 a 78% de sua atividade quando a hemolinfa é pré-incubada a 50ºC de 2 a 15 minutos, respectivamente. Considerando os altos níveis de ADA encontrados pode-se inferir que, em animais sadios e alimentados, a adenosina é mantida em baixas concentrações na hemolinfa. Tendo a atividade da enzima permanecido constante frente à larga faixa de pH testada, sugere-se que a ADA pode atuar com eficiência mesmo em situações adversas que determinem variações no pH da hemolinfa.

Immune status with empyema thoracis.

OBJECTIVE: To evaluate the humoral and cell mediated immune status of children with empyema thoracis. METHODS: Serum IgG, IgA, IgM, Complement C3 assay and cell mediated immunity (CMI) tests were performed in 33 patients of empyema thoracis, and 14 healthy age matched controls. RESULTS: The mean serum IgG and IgA levels in empyema thoracis and its subgroups were significantly raised as compared to controls. The overall values of IgG and IgA were 104% (p<0.001) and 114% (p<0.01) of normal mean, respectively. The mean serum IgM and complement C3 levels did not differ significantly in both the groups. The frequency of negative skin reaction to purified protein derivative (PPD) was significantly higher in children with empyema thoracis as compared to controls (p<0.05). The mean absolute lymphocyte count (ALC) was significantly decreased and serum adenosine deaminase (ADA) activity was significantly raised in empyema thoracis in comparison to controls. The overall ALC was 76.1% (p<0.01) and serum ADA activity was 169.4% (p<0.001) of normal mean, respectively. No significant differences were observed in the mean levels of immunoglobulins, complement C3 and CMI tests between pyothorax and pyopneumothorax and pleural fluid culture positive and negative cases. CONCLUSIONS: Thus, both humoral and cell mediated immunity were affected in empyema thoracis patients. However, CMI demonstrated more pronounced change in comparison to humoral immunity.

role of xanthine oxid and andenosine deaminase in the oxidative stress of rheumatoid arthritis

Rheumatoid arthritis [RA] is an autoimmune connective tissue disease in which chemotaxis and excessive production of cytokines and reactive oxygen species [ROS] are characteristics of activated cytokines that play an important role in the generation of ROS in RA. Xanthine oxidase [XO] and adenosine deaminase [ADA] enzymes were reported to act as sources of ROS and advanced oxidation protein products [AOFP] was found to be a good marker of oxidative stress. To find out if XO or ADA has any role in the pathogenesis of RA; and to correlate their activities with a novel marker of oxidative stress, other cytokines, and markers of disease activities.: this study was carried out on 10 patients with RA [group I] and 10 healthy persons as a control group, [group II]. The levels of XO activity, ADA activity, AOPP, interleukin-6 [IL-6], interleukin-8 [JL-8], erythrocyte sedimentation rate [ESR] and C-reactive protein [CRP] were estimated. XO activity, A OFF, IL-6, IL-8, ESR and CRF levels were all increased significantly in group I. Also XO and AOPP were found to have positive correlation to each other and to the acute phase reactants ESR and CRP. ADA activity showed no significant changes comparing the two studied groups. XO could be considered an important source of ROS in RA patients. XO and AOFP play at least a partial role in the pathogenesis of the disease and their levels could be used as one of the laboratory markers of the RA activity. On the other hand, ADA had no role in RA pathogenesis. It is suggested that the use of xanthine oxidase inhibitors as well as other antioxidants may be of benefit in preventing tissue damage in RA patients

Early clinical and angiographic outcome of coronary stenting in thrombus-containing lesions

Percutaneous coronary intervention [PCI] and coronary stenting of thrombus-containing lesions have frequently been associated with an increased risk of adverse outcome. However, the strength of this association has varied and with the new antiplatelet agents and stents, it is not clear whether thrombus is still a risk factor after PCi. The study evaluated the early [in-hospital] clinical and angiographic outcomes of patients undergoing coronary stenting in lesions with angiographic evidence of intracoronary thrombus, A retrospective study comparing two groups of patients: Group I included 64 patients who undetwent stent implantation in a single thrombus containing lesion, Group II included 293 patients who underwent stent implantation in a single non-thrombus containing lesion during the same time period [between June 1997 and April 2001]. Both groups were matched as regards the baseline clinical characteristics except that significantly more patients of group I were presented by unstable angina compared with group II: 65.08% versus 47.78% [P<0.01]. Patients with thrombus [Group I] have significantly more RCA as the target vessel; 46.03% vs 30.03% [P<0.01] and significantly more complex lesion morphology; 42.86% vs 26.28% [P<005] compared with patients without thrombus [Group II]. The target vessel size and the baseline percent diameter stenosis were significantly higher In group I than group II [P<0.001 and P<0.01 respectively]. Similarly the largest balloon diameter and the mean number of inflations were significantly higher in group 1 than group II [P<0.001 and P<0.001 respectively]. Significantly more patients in group I received the GPIIb/I1Ia antagonist, tirofiban [Aggrastat] than group Ii; 20.63% vs 4.10% [P<0.001] although its use was rather limited in both groups. The angiographic success was almost identical for both groups 95.24% in group I vs 96.25% in group II. There were no statistically significant differences between both groups regarding all parameters of in-hospital outcomes, However, there was a trend towards more adverse events in group I compared to group II that did not reach statistical significance [Death: 1.59% vs 0.34%, Q-Mi: 3.17% vs 1.71%, Acute closure: 4.76% vs 2.05%, Repeat PCI: 4.76% vs 2.38%, Emergency CABG: 0% vs 0%, and Procedural success: 88.8% vs 94.28%]. Coronary stenting can be safely performed in patients with thrombus-containing lesions with excellent angiographic outcome and acceptable, though less favorable in-hospital clinical outcome