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Value of adenosine deaminase in the diagnosis of tuberculous pleural effusions in young patients in a region of high prevalence of tuberculosis.

BACKGROUND: Pleural biopsy is usually considered important for the diagnosis of pleural effusions, especially for distinguishing between tuberculosis and neoplasia, even though tuberculous pleural fluid contains sensitive biochemical markers. In regions with a high prevalence of tuberculosis, and in patient groups with a low risk of other causes of pleurisy, the positive predictive value of these markers is increased. The criteria for performing a pleural biopsy under these circumstances have been investigated, using adenosine deaminase (ADA) as a pleural fluid marker for tuberculosis. METHODS: One hundred and twenty nine patients with a pleural effusion aged < or = 35 years (mean (SD) 25.2 (4.9) years) were studied. Seventy three were men. Eighty one effusions (62.8%) were tuberculous, 12 (9.3%) parapneumonic, and 10 (7.7%) neoplastic, five were caused by pulmonary thromboembolism, four by systemic lupus erythematosus, seven by empyema, three following surgery, one was the result of asbestosis, and one of nephrotic syndrome. In five cases no definitive diagnosis was reached. ADA levels were determined by the method of Galanti and Giusti. RESULTS: The diagnostic yield of procedures not involving biopsy was 94.5% (122/129). Pleural biopsy provided a diagnosis in a further two cases, but not in the remaining five. All tuberculous cases had pleural fluid levels of ADA of > 47 U/l (mean (SD) 111.1 (36.6) U/l). The only other cases in which ADA exceeded this level were six of the seven patients with empyema. Cytological examination of the pleural fluid diagnosed eight of the 10 neoplastic cases, compared with six diagnosed by pleural biopsy. CONCLUSIONS: In a region with a high prevalence of tuberculosis procedures not involving pleural biopsy have a very high diagnostic yield in patients with a pleural effusion aged < or = 35 years, making biopsy necessary only in cases in which pleural levels of ADA are below 47 U/l, pleural fluid cytology is negative and, in the absence of a positive basis for some other diagnosis, neoplasia is suspected.

Adenosine Deaminase↗

Artificial neural networks analysis of surface-enhanced laser desorption/ionization mass spectra of serum protein pattern distinguishes colorectal cancer from healthy population.

PURPOSE: The low specificity and sensitivity of the carcinoembryonic antigen test makes it not an ideal biomarker for the detection of colorectal cancer. We developed and evaluated a proteomic approach for the simultaneous detection and analysis of multiple proteins for distinguishing individuals with colorectal cancer from healthy individuals. EXPERIMENTAL DESIGN: We subjected serum samples (including 55 colorectal cancer patients and 92 age- and sex-matched healthy individuals) from 147 individuals, for analysis by surface-enhanced laser desorption/ionization (SELDI) mass spectrometry. Peaks were detected with Ciphergen SELDI software version 3.0. Using a multilayer artificial neural network with a back propagation algorithm, we developed a classifier for separating the colorectal cancer groups from the healthy groups. RESULTS: The artificial neural network classifier separated the colorectal cancer from the healthy samples, with a sensitivity of 91% and specificity of 93%. Four top-scored peaks, at m/z of 5,911, 8,930, 8,817, and 4,476, were finally selected as the potential "fingerprints" for detection of colorectal cancer. CONCLUSIONS: The combination of SELDI-TOF mass spectrometry with the artificial neural networks in the analysis of serum protein yields significantly higher sensitivity and specificity values for the detection and diagnosis of colorectal cancer.

Adult↗

Clinical value of creatinine kinase in the diagnosis of ectopic pregnancy.

The role of creatinine kinase (CK) in the diagnosis of ectopic pregnancy was studied. We selected 56 patients divided into 4 groups. Group A consisted of 10 patients with asymptomatic tubal pregnancy, group B consisted of 11 patients with symptomatic tubal pregnancy whereas groups C and D consisted of 20 and 15 patients with normal and threatened intrauterine pregnancy, respectively. Serum samples of CK were taken from all patients on admission. No significant difference was observed in the median CK value of cases with normal pregnancy (58.5 +/- 7.24 U/1, mean +/- SE) as well as threatened abortion (73 +/- 11.43 U/1) compared to that of cases with asymptomatic 58.5 +/- 12.42 U/1) or symptomatic tubal pregnancy (59 +/- 10.08 U/1). We conclude that serum CK is not a useful biochemical marker in the diagnosis of ectopic pregnancy.

Abortion, Threatened↗

Antioxidant and oxidative stress indices in dialysis-dependent acute renal failure.

BACKGROUND: Experimental animal models and in vitro studies have established a role for reactive oxygen species and the therapeutic potential for free radical scavengers in acute renal failure (ARF). Little is known of the effects of hemodialysis and other clinical variables on antioxidant defenses and oxidative stress among patients with ARF. METHODS: We examined antioxidant defenses and oxidative stress status in 24 patients with ARF requiring hemodialysis (HD). Blood samples were drawn prior to the first dialysis session (baseline), as well as before and after the third and sixth dialysis sessions. At each time point, the following parameters were measured: plasma alpha-tocopherol (vitamin E), plasma glutathione peroxidase (GSH-Px), serum total oxygen radical absorbance capacity (ORAC), plasma thiobarbituric acid reactive substances (TBARS), plasma tumor necrosis factor-alpha (TNF-alpha), and interleukin-10 (IL-10). Multivariate linear regression analyses were performed to examine clinical/laboratory variables associated with antioxidant/oxidative stress indices. The changes in antioxidant/oxidative stress indices over time after initiation of hemodialysis was evaluated in a subgroup of patients (n = 11) who completed six dialysis sessions. Intradialytic changes in antioxidant/oxidative stress indices and the differential impact of cellulose acetate vs. polysulfone dialyzers were also evaluated. RESULTS: Factors associated with alpha-tocopherol level were serum albumin (301 microg/dl upward arrow for each 1 g/dl upward arrow in albumin) and ORAC (188 microg/dl upward arrow for each 1,000 micromol Trolox Eq/l upward arrow in ORAC). Age was independently associated with plasma GSH-Px levels (55 U/l downward arrow for each 10-year age upward arrow ). Factors associated with ORAC were alpha-tocopherol (85 micromol Trolox Eq/l upward arrow for each 100 microg/dl upward arrow in alpha-tocopherol) and total bilirubin (30 micromol Trolox Eq/l downward arrow for each 1 mg/dl upward arrow in total bilirubin). Total bilirubin was independently associated with TBARS (0.2 microM upward arrow for each 1 mg/dl upward arrow in total bilirubin). GSH-Px and ORAC levels declined over time between baseline and the sixth dialysis session (p < 0.05 for both). Finally, there was a significant intradialytic decline in ORAC levels, which appeared to be more pronounced with use of cellulose acetate compared with polysulfone dialyzer membranes (p < 0.05). CONCLUSIONS: These observations indicate that antioxidant and oxidative stress indices in ARF patients are associated with several clinical and laboratory variables as well as the dialysis procedure. Further studies are needed to investigate the therapeutic role of anti-oxidant therapy in these patients.

Acute Kidney Injury↗

Endothelin-1 is increased in the breath condensate of patients with non-small-cell lung cancer.

UNLABELLED: One recent line of cancer research is currently directed to the study of growth factors. Of increasing interest is endothelin-1 (ET-1), a mitogenic factor already investigated in several human cancer cell lines, which has been found to participate in the development and progression of tumours. This peptide has an important role also in non-small-cell lung cancer (NSCLC) where ET-1 expression has been found in 100% of cell lines. OBJECTIVES: The aim of this study was to measure ET-1 concentrations in the airways of patients with NSCLC using a completely non-invasive procedure--the breath condensate--and to verify the involvement of this peptide in the growth of lung tumours. METHODS: We enrolled 30 patients (17 men, median age 63 years; range 53-74) with histological evidence of NSCLC and 15 healthy controls (9 men, median age 59 years; range 52-70). ET-1 was measured in the exhaled breath condensate by means of a specific enzyme immunoassay kit. RESULTS: Higher concentrations of exhaled ET-1 were found in NSCLC patients (8.3 +/- 0.7 pg/ml) compared to controls (5.2 +/- 0.5 pg/ml, p < 0.0001). A statistically significant difference was observed between patients with distant metastases (stage IV) of NSCLC (8.9 +/- 0.6 pg/ml) and those with locoregional disease (stage I-III) (7.9 +/- 0.5 pg/ml). A significant reduction in ET-1 levels was found in 14 patients after surgical removal of the tumour either associated with or without adjuvant chemotherapy (6.3 +/- 0.5 vs. 7.9 +/- 0.4 pg/ml, p < 0.0001). CONCLUSIONS: These findings suggest that the measurement of ET-1 in the breath condensate of patients with NSCLC could be proposed as a marker for early detection of NSCLC as well as for monitoring reduction or progression of the neoplasm in the follow-up of treated patients.

Aged↗

Role and modulation of CD16 expression on eosinophils by cytokines and immune complexes.

BACKGROUND: Blood eosinophils express CD16 on their surface when stimulated in vitro with platelet-activating factor or IFNgamma. Transient expression of CD16 is also observed in vivo following aeroallergen challenge of asthmatic subjects. The present work is aimed at evaluating the possible mechanisms modulating eosinophil expression of CD16 and the biological functions of this receptor. METHODS: First, purified blood eosinophils were incubated with IL-1beta, IL-2, IL-4, IL-5, IL-9 or IL-16, GM-CSF, IFNgamma, eotaxin or 5-oxo-ETE and CD16 expression was measured. Second, the capacity of CD16 to mediate degranulation induced by IgG immune complexes (IC) was evaluated in eosinophils with low and high CD16 expression. Finally, serum allergen-specific IgE and IgG, and total IgE levels were measured at baseline in allergic asthmatics and correlated with changes observed in blood eosinophil CD16 expression (DeltaCD16) following allergen challenge. RESULTS: Only IFNgamma and IL-2 significantly increased the number of CD16+ eosinophils, respectively, 37 +/- 10% (p = 0.0038) and 38 +/- 8% (p = 0.0006), compared to control, 7 +/- 2%. IgG IC induced degranulation in eosinophils with low and high CD16 expression and monoclonal anti-CD16 and anti-CD32 antibodies inhibited this. IgG IC increased eosinophil CD16 expression (14 +/- 6%, p = 0.0008) and this effect was blocked by pretreatment with anti-CD32 antibodies. DeltaCD16 following allergen challenge correlated with the specific IgG/total IgE ratio (r(2) = 0.41, p = 0.036). CONCLUSION: These data suggest that formation of IgG IC is associated with surface eosinophil CD16 expression in asthma and that CD16 in cooperation with CD32 mediates IC-induced degranulation.

Antibody Specificity↗

Greater involvement of neurokinins found in Guinea pig models of severe asthma compared with mild asthma.

BACKGROUND: Involvement of neurokinins in asthma has been previously pointed out by several reports. However, the relationship between neurokinins and the severity of asthma has remained unclear. We developed a model of mild asthma (model I) and severe asthma (model II) in guinea pigs, and investigated the function of neurokinins in both models. METHODS: In models I and II, systemically sensitized guinea pigs were made to inhale ovalbumin once and three times, respectively. Substance P (SP) and neurokinin A (NKA) concentrations in the bronchoalveolar lavage fluid (BALF) were measured in models I and II. Then, the effects of a capsaicin pretreatment, which depletes neurokinins, in both animal models on airway narrowing induced by the last ovalbumin inhalation, airway hyperresponsiveness to inhaled methacholine, and eosinophil accumulation in BALF, were investigated. RESULTS: SP concentration tended to increase and the NKA concentration increased significantly in model II, but not in model I. Capsaicin pretreatment significantly inhibited the late bronchial response that was observed 2-6 h after the last ovalbumin inhalation, airway hyperresponsiveness and eosinophil accumulation in model II. On the other hand, it had no effects on the responses in model I. CONCLUSION: It is suggested that the more severe the disease, the greater the involvement of neurokinins.

Administration, Inhalation↗

Decrease of interleukin-10-producing T cells in the peripheral blood of severe unstable atopic asthmatics.

BACKGROUND: Although IL-10 is known as an immunoregulatory cytokine produced by various cells including T cells, its basic profile in atopic asthma remains uncertain. OBJECTIVE: The profiles of IL-10 production in circulating CD4+ T cells of atopic asthmatics were investigated with respect to clinical severity. METHODS: Forty atopic asthmatics were divided into three groups: mild, and severe but stable and severe unstable asthmatics. Eosinophils were counted in the peripheral blood and sputum, and exhaled nitric oxide was assessed. PBMCs were stimulated with or without anti-CD3 and anti-CD28 antibodies and then processed for detecting IL-10-producing CD4+ cells using flow cytometry. RESULTS: There was no difference in the eosinophil count in blood or sputum and in nitric oxide level among the three groups. IL-10-producing CD4+ cells were mainly detected in a CD45RO+ memory population. The frequency of IL-10-producing cells after stimulation was significantly lower in the severe unstable group compared to the mild group. In addition, the frequency of IL-10-producing cells in the severe unstable group was significantly lower than that in the severe stable group despite the fact that both groups received similar treatments with high-dose inhaled corticosteroids. The IL-10 production of CD4+CD45RO+ cells in response to dexamethasone did not differ among the three groups. CONCLUSIONS: IL-10-producing CD4+CD45RO+ cells in the peripheral blood are decreased in severe unstable asthmatics, which is not explained by the effect of high-dose inhaled corticosteroid medication.

Adult↗

Studies on precursor proteins PIVKA-II, -IX, and -X in the plasma of patients with 'hemorrhagic disease of the newborn'.

Factors II, IX, and X in the plasmas of 10 patients with 'hemorrhagic disease of the newborn' were investigated by means of electroimmunoassay and crossed immunoelectrophoresis (CIE). The biological activity was within 4.2-30 U/dl for factor II, 5.1-20 U/dl for factor IX, and 5.2-24 U/dl for factor X, whereas the immunological antigen was within 33-58, 25-50, and 35-60 U/dl, respectively. Thus, for all factors, 1.7 times more antigen than activity was present. The CIE pattern of factors II and IX in the presence of Ca++ ions clearly showed a biphasic precipitin arc, and in the absence of Ca++ ions, only one precipitin arc was observed. These results implied the presence of precursor proteins PIVKA-II and -IX in the plasma. However, even in the presence of Ca++ ions the CIE pattern of factor X antigen in the patient plasmas only showed a single precipitin arc with a slightly faster than normal electrophoretic mobility. PIVKA-II, -IX, and the abnormal factor X antigen (PIVKA-X) disappeared within 24 h after the patients were treated with vitamin K.

Adult↗

Natural cytotoxicity in adult acute leukemia.

Natural cytotoxic activity was studied in 32 adult patients with acute non-lymphoid leukemia (ANLL) and 27 adult patients with acute lymphoblastic leukemia (ALL). Thirteen patients with active ANLL had a significantly reduced natural cytotoxicity in peripheral blood compared with that of healthy controls, 5.0 +/- 3.4 versus 27.1 +/- 11.5 (p less than 0.0005). Patients with ANLL in remission had a normal natural cytotoxicity (p greater than 0.05). Patients with active ANLL had a significantly reduced number of Leu-7-positive cells (p less than 0.001), while patients in remission had normal proportions of these cells (p greater than 0.05). Peripheral blood from patients with ALL showed reduced natural killer (NK) cell activity, both in active disease and in remission (p less than 0.0005). The percentage of Leu-11b (CD 16)-positive cells was increased in patients in remission from ALL (p less than 0.05). Bone marrow cells from patients with ALL in remission had a reduced natural cytotoxicity, 2.8 +/- 4.0 versus 16.3 +/- 9.0 in bone marrow controls (p = 0.01). In contrast, patients with ANLL in remission showed a normal bone marrow cytotoxicity (p greater than 0.05) while patients with active ANLL had a reduced NK cell activity (p less than 0.03). The low NK activity observed in leukemic patients may be of importance for the pathogenesis of the diseases. Acute non-lymphoid leukemia (ANLL) is a malignant disease of the multipotential hemapoietic stem cell. The stem cell is capable of differentiating into various cell lineages, i.e. erythroid, granulocytic, monocytic and megacariocytic cell lineages.(ABSTRACT TRUNCATED AT 250 WORDS)

Acute Disease↗

Use of soluble fibrin antigen instead of D-dimer as fibrin-related marker may enhance the prognostic power of the ISTH overt DIC score.

The overt DIC score of the DIC subcommittee of the ISTH includes a fibrin-related marker (FRM) as indicator of intravascular fibrin formation. The type of marker to be used has not been specified, but D-dimer antigen, or fibrin degradation products are used by most investigators. Soluble fibrin complexes have been suggested as more specific indicators of acute intravascular fibrin formation. The aim of the present study was to compare the predictive value of the overt DIC score concerning clinical outcome in a surgical intensive care cohort, using either D-dimer antigen, or soluble fibrin antigen as FRM. The cutoff values for 2 and 3 score points for the FRM were assigned on the basis of the 25% and 75% quartiles of 1870 plasma samples obtained from 359 ICU patients during a period of 6 months. For 331 patients with complete diagnostic workup and day 1 blood samples, the Iatro SF as FRM component of the overt DIC score displayed the highest prognostic power concerning clinical outcome. The 28-day mortality of patients with overt DIC at day 1, using Iatro SF as FRM assay was 50.0%, whereas 28-day mortality of patients without overt DIC was 14.0% (p <0.0001). Using MDA D-dimer, and TINAquant D-dimer, 28-day mortality was between 35.5% and 39.3% in patients with overt DIC, and 15.5% to 15.6% in patients without overt DIC. Selection of the FRM as component of the DIC score has a small, but relevant impact on the prognostic performance of the overt DIC score. The present data on the distribution of values may provide a basis for the selection of appropriate cutoff points for assigning 2, and 3 points in the score.

Adolescent↗

Effect of recombinant factor VIIa on melagatran-induced inhibition of thrombin generation and platelet activation in healthy volunteers.

The objectives were to investigate whether activation of the extrinsic coagulation cascade by recombinant factor VIIa (rFVIIa) reverses the inhibition of thrombin generation and platelet activation by melagatran, the active form of the oral direct thrombin inhibitor ximelagatran. In a single-blind, randomized, parallel-group study, volunteers (20 per group) received a 5-hour intravenous (i.v.) infusion to achieve steady-state melagatran plasma concentrations of approximately 0.5 micromol/L, with a single i.v. bolus of rFVIIa (90 microg/kg) or placebo at 60 minutes. Prothrombin fragment 1+2, thrombin-anti-thrombin complex, fibrinopeptide A, beta-thromboglobulin, and thrombin-activatable fibrinolysis inhibitor were quantified for venous and shed blood. Activated partial thromboplastin time (APTT), prothrombin time (PT), endogenous thrombin potential, thrombus precursor protein (TpP), and plasmin-alpha(2)-antiplasmin complex concentrations were determined in venous blood. Shed blood volume was measured. Melagatran reduced markers of thrombin generation and platelet activation in shed blood and prolonged APTT. rFVIIa increased FVIIa activity, PT, and TpP in venous blood. All other parameters were unaffected. In conclusion, rFVIIa did not reverse the anticoagulant effects of high constant concentrations of melagatran. However, the potential value of higher, continuous or repeated doses of rFVIIa or its use with lower melagatran concentrations has not been excluded.

Adult↗

C-reactive protein, fibrin D-dimer, and risk of ischemic heart disease: the Caerphilly and Speedwell studies.

BACKGROUND: There is increasing interest in the predictive value of C-reactive protein (CRP) and fibrin D-dimer in the prediction of ischemic heart disease (IHD). We assessed their joint and independent associations with IHD in a large combined analysis of 2 population cohorts. METHODS AND RESULTS: Men aged 49 to 66 years from the general populations of Caerphilly and Speedwell were studied between 1982 and 1988 and re-examined for new IHD events at fixed intervals of approximately 105 months (Caerphilly) and 75 months (Speedwell). 3213 men had CRP and D-dimer measured at baseline and 351 (11%) had a new IHD event. Mean levels of CRP and D-dimer were significantly higher among men in whom IHD developed. The relative odds of IHD in men in the top 20% of the distribution of CRP was 2.97 (95% CI, 2.04, 4.32) and for D-dimer was 2.40 (95% CI, 1.69, 3.40); CRP and D-dimer had additive effects on risk of IHD. Multivariate analysis reduced the size of the relative odds, which remained significant for D-dimer. CONCLUSIONS: Both inflammatory and thrombogenic markers are important (and potentially additive) predictors of coronary risk.

Aged↗

Cardiac troponin I. A marker with high specificity for cardiac injury.

BACKGROUND: Levels of MBCK can be increased in patients with skeletal muscle injury or renal failure in the absence of myocardial injury, causing diagnostic confusion. This study was designed to determine whether measurement of cardiac troponin I (cTnI), a myocardial regulatory protein with comparable sensitivity to MBCK, has sufficient specificity to clarify the etiology of MBCK elevations in patients with acute or chronic skeletal muscle disease or renal failure. METHODS AND RESULTS: Of the patients (n = 215) studied, 37 had acute skeletal muscle injury, 10 had chronic muscle disease, nine were marathon runners, and 159 were chronic dialysis patients. Patients were evaluated clinically, by ECG, and by two-dimensional echocardiography. Total creatine kinase (normal, < 170 IU/L) was determined spectrophotometrically, and cTnI (normal, < 3.1 ng/mL) and MBCK (normal, < 6.7 ng/mL) were determined with specific monoclonal antibodies. Values above the upper reference limit were considered "elevated." Elevations of total creatine kinase were common, and elevations of MBCK occurred in 59% of patients with acute muscle injury, 78% of patients with chronic muscle disease and marathon runners, and 3.8% of patients with chronic renal failure. Some of the patients were critically ill; five patients were found to have had myocardial infarctions and one had a myocardial contusion. cTnI was elevated only in these patients. CONCLUSIONS: Elevations of cTnI are highly specific for myocardial injury. Use of cTnI should facilitate distinguishing whether elevations of MBCK are due to myocardial or skeletal muscle injury.

Adult↗

In vivo salicylate hydroxylation: a potential biomarker for assessing acute ozone exposure and effects in humans.

Ozone is known to yield hydroxyl radical, which may contribute to ozone-mediated lung injury. In the presence of hydroxyl radical, salicylate is hydroxylated to form 2,3-dihydroxybenzoic acid (2,3-DHBA). There is no evidence of enzymatic formation of 2,3-DHBA. We hypothesized that salicylate hydroxylation might be used as a biomarker indicating human exposure to ozone. Healthy, nonsmoking volunteers, 18 to 34 yr of age, were given acetylsalicylic acid (975 mg) or placebo orally 0.5 h before an exposure. Subjects were exposed to ozone (0.12 or 0.4 ppm) or filtered air in an environmental chamber for 2 h, while performing intermittent exercise. Results indicate significant decrements in FVC, FEV1.0, forced expiratory flows at 50% and 75% of FVC, and peak expiratory flow rate, and an increase in airway resistance, after exposure to 0.4 ppm ozone in comparison with air control (p < 0.05). Exposure to 0.4 ppm ozone also resulted in increased symptom numbers and severity (p < 0.05). When subjects were exposed to 0.12 ppm ozone, changes of pulmonary function and symptoms reported were minimal. Plasma concentration of 2,3-DHBA was significantly increased after exposure to 0.12 and 0.4 ppm ozone in comparison with air control (p < 0.05). There was a significant correlation between ozone-induced changes of pulmonary function and normalized salicylate hydroxylation (p < 0.05). The results indicate that exposure to ozone can initiate in vivo production of hydroxyl radical, a potent reactive agent. Salicylate hydroxylation may then serve as a sensitive dosimetric biomarker for ozone exposure, even at subclinical ozone exposure levels.

Adolescent↗