Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound

---

Query: EC:2.6.1.2 (alanine aminotransferase)
26,722 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The value of a diagnostic test depends on most cases on its ability to discriminate between patients with and without a certain disease. One way of evaluating a diagnostic test is to use the relative operating characteristic curve (ROC curve) and the differential positive rate (DPR). The ROC curve displays the relationship between the true positive ratio and the false positive ratio for a range of cutoff values and it can be used to compare various diagnostic tests under equivalent conditions (equal true positive ratios or false positive ratios) and over the entire range of cutoff values. The DPR is the difference between the true positive ratio and the false positive ratio at various cutoff values and it can be used to obtain the cutoff value associated with the highest sensitivity and specificity. The purpose of this study was to describe the evaluation and comparison of diagnostic tests using ROC curves and DPR. Eventually, the positive and negative predictive values were used to assess the differences between the sensitivity and specificity obtained when the upper limit of the reference interval, or the optimal cutoff value indicated by the DPR, was used as cutoff value. To illustrate the methods, the 2 h post-prandial total serum bile acid concentration (PSBA) and the alanine aminotransferase activity (ALAT) in the diagnosis of primary or secondary hepatobiliary diseases in dogs were used. The ROC curves showed, as expected from previous studies, that PSBA was superior to ALAT in diagnosing dogs with hepatobiliary diseases. Using DPR, the optimal cutoff value for PSBA was suggested to be 15.48 mumol/l. Compared to the traditionally used cutoff value of 22.24 mumol/l, no decisive difference in the positive predictive values were observed. However, the cutoff value of 15.48 mumol/l appeared to produce higher negative predictive values compared to a cutoff value of 22.24 mumol/l. Seemingly, ROC curves and DPR are simple methods useful to the evaluation of diagnostic tests and due to the simplicity, there seems to be a great potential for these methods in the evaluation of diagnostic tests in veterinary medicine.
...
PMID:Evaluation of diagnostic tests using relative operating characteristic (ROC) curves and the differential positive rate. An example using the total serum bile acid concentration and the alanine aminotransferase activity in the diagnosis of canine hepatobiliary diseases. 145 34

Eighty-three patients suffering from upper abdominal pain were studied to evaluate the contribution of commonly used biochemical markers in the diagnosis of acute pancreatitis. On admission to hospital, serum amylase, lipase, total bilirubin, aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase and gamma-glutamyl transferase activities were measured. By stepwise logistic discrimination, only two determinations appeared to be of clinical value: lipase and alkaline phosphatase activities. A classification rule was established including these two measurements and its diagnostic performance evaluated by a jackknifed method amounted .83%. ROC curves were used to assess sensitivity and specificity. Our study clearly shows that serum lipase measurements should be preferred to amylase measurements, and that our two-test classification rule provides an efficient aid in clinical decision-making.
...
PMID:Combined diagnostic value of biochemical markers in acute pancreatitis. 169 97

The translation into Spanish of the AUA/International Prostatic Symptom (AUA/IPS) Score hadn't been validated in spanish. METHODS. AUA/IPS questionnaire was self administered by 103 consecutive patients and by 24 healthy volunteers. An alternative formulation to question 4 (ALT-4) was added. RESULTS. 51 patients (49%) and 17 controls (79%) completed al questions (Feasibility). Reliability was measured by: a) Crohnbach's alpha (0.68 and 0.70 with ALT-4) b) Kendall's coefficient of concordance (0.097, significance < 0.001) and c) retesting 17 patients within 2 months. The relation of the AUA/IPS scores with quality of life (Construct validity) showed a Spearman's correlation coefficient of 0.57 (confidence = 0.0001), and 0.52/0.0004 with ALT-4. The relation with uroflowmetry (Concurrent empirical validity) was poor as shown in ROC curves. CONCLUSIONS. The Spanish version of the AUA/IPS questionnaire given in an easy format improves feasibility without alteration of reliability or validity. The relation of the AUA/IPS score with uroflowmetry is poor, although the questionnaire can be considered valid and reliable.
...
PMID:[The IPPS questionnaire in patients and controls. Psychometric validation]. 753 74

Excessive alcohol consumption is a major health problem in the UK leading to both serious morbidity and mortality. This study compared newer potential biochemical markers of excessive alcohol consumption [carbohydrate-deficient transferrin (CDT), mitochondrial AST (mAST) and alpha glutathione-s-transferase (alpha-GST)] with conventional markers (AST, ALT, GGT, MCV). Patients (n = 85) were enrolled in the study and subdivided into several groups on the basis of alcohol consumption. Patients with non-alcoholic liver disease (NALD) (n = 40) were also enrolled. All the markers, with the exception of the ratio mAST/total AST were significantly higher in heavy drinkers/alcoholics compared to teetotallers/social drinkers (p < 0.05). mAST and AST/ALT ratio were significantly higher in alcoholics compared to NALD (p < 0.01), whereas ALT was higher in the NALD group (p < 0.05). Multivariate discriminant function analysis (Wilks method) demonstrated that the logarithmic functions of AST/ALT ratio and mAST could correctly classify 87.9% of cases into either the alcoholic or NALD groups. ROC plot analysis showed that AST, mAST and GGT were the best markers at distinguishing heavy consumption of alcohol from lesser levels and that AST/ALT ratio and mAST were the best in distinguishing alcoholics from NALD. In conclusion, none of the newer biochemical markers, with the exception of mAST, offers any major advantage over the conventional markers.
...
PMID:Biochemical markers of alcohol abuse. 872 55

We measured serum creatine kinase (CK), lactate dehydrogenase (LD), aspartate aminotransferase (AST), and serum alanine aminotransferase (ALT) in 26 heat stroke (HS) victims and 10 control (non-heat-exhausted) subjects during annual Hajj in Makkah, Saudi Arabia. On admission to the HS treatment unit, serum CK, AST, ALT, and LD were higher in HS victims than controls (P < 0.05), and at 6, 12, and 24 h were higher than baseline concentration. The patient group was divided into three groups, (a) those who had a quick recovery, (b) those who were critically ill until the end of the Hajj period (7 days), and (c) those who died. Serum enzymes at the time of admission were significantly higher (P < 0.05) in the nonsurviving group (n = 6) and the severely ill (n = 9) than in those who had a quick recovery (n = 11). ROC curves were plotted for each enzyme. The most useful indicator was LD, as it could distinguish significantly between the groups who died and those who had a quick recovery (area under the curve = 0.991 +/- 0.0286). It was followed by CK and AST as useful prognostic factors. When compared with ROC curves for body temperature, anion gap, and serum potassium, the enzyme results were superior prognostic indicators.
...
PMID:Serum enzymes in heat stroke: prognostic implication. 921 54

As chronic liver disease progresses, an imbalance occurs between synthesis and breakdown of extracellular matrix (ECM). Matrix metalloproteinases (MMPs) are involved in degrading ECM while tissue inhibitors of metalloproteinases (TIMPs) prevent their fibrolytic action. We determined if plasma levels of MMP-2, TIMP-1 and TIMP-2 are related to liver histology in patients with chronic hepatitis C. Plasma MMP-2, TIMP-1 and TIMP-2 levels were measured in 43 patients with chronic hepatitis C. Plasma levels of MMP-2, TIMP-1 and TIMP-2 and serum ALT were correlated with liver biopsy score and specificity and sensitivity of the assays in detecting advanced liver disease were calculated from ROC analysis. Plasma TIMP-1 was significantly correlated with histological activity index (r = 0.45), portal inflammation (r = 0.48), periportal necrosis (r = 0.34) and focal necrosis (r = 0.38). Plasma TIMP-2 was significantly correlated with fibrosis (r = 0.43) and confluent necrosis (r = 0.41). Using ROC analysis both TIMP-1 and TIMP-2 had significant diagnostic ability in detecting advanced liver disease (Area under the curve 0.73 for both, p 0.015 and 0.036 respectively). A normal plasma TIMP-1 excluded advanced liver disease. Neither plasma MMP-2 or serum ALT were related to fibrosis or to histological activity index. With increased severity of liver disease in chronic hepatitis C there is increased plasma levels of TIMPs -1 and -2. Plasma TIMP-1 and TIMP-2 are sensitive and to a lesser extent specific in detecting advanced liver disease in chronic hepatitis C and could be used in preference to serum ALT.
...
PMID:Plasma levels of matrix metalloproteinase-2 (MMP-2) and tissue inhibitors of metalloproteinases -1 and -2 (TIMP-1 and TIMP-2) as noninvasive markers of liver disease in chronic hepatitis C: comparison using ROC analysis. 1008 Jan 60

The objectives of this study included: 1) to identify pretreatment variables predictive of absence of response in 107 patients with chronic hepatitis C, genotype 1, treated with interferon-a (IFN-a) at a dose of 3 MU three times weekly for 3-12 months and classified into two groups: group A, nonresponders vs. patients with a complete response, and group B, nonresponding and relapsing patients vs. patients with a sustained response; and 2) to establish a prognostic index using ROC curve analysis. The rate of sustained response was 6. 5&#37; at the 24-month follow-up. The pretreatment characteristics with predictive value using ROC curves were as follows: in group A, age, GGT, serum ferritin, viral load, and grade and stage of the histological lesion; and in group B, known duration of infection, GPT, GGT, serum ferritin, viral load, and grade and stage of the histological lesion. In both group A and group B the positive predictive value (the probability of predicting an absence of response when the variable is present) was greater than the negative predictive value (mean: 84.3% vs. 41.1%, 99% vs. 16.5%, respectively). In group A, based on the prognostic index, the positive predictive value when three variables were present was 96&#37; and the sensitivity was 63.5&#37;, with the test being unequivocal in 6.5&#37;, whereas when four or five variables were present, the positive predictive value was 97&#37; and 100&#37; and the sensitivity was 40.5&#37; and 18&#37;, respectively. In group B, the positive predictive value when two variables were present was 100&#37; and the sensitivity was 87&#37;, whereas when three, four, five and six variables were present the sensitivity was between 73&#37; and 28&#37;. In group A, age, GGT and ferritin were the predictive variables independently associated with an absence of response, with a relative risk of 6.5, 4.8 and 3.1, respectively, whereas in group B we did not find variables independently associated with an absence of response. It was concluded that in patients with genotype 1, it is possible to predict the absence of response to IFN therapy with a high degree of reliability.
...
PMID:[ROC curve analysis of factors predictive of non-response to interferon treatment in patients with chronic hepatitis C, genotype 1]. 1085 25

The objectives of this study included: 1) to identify pretreatment variables predictive of absence of response in 107 patients with chronic hepatitis C, genotype 1, treated with interferon-a (IFN-a) at a dose of 3 MU three times weekly for 3-12 months and classified into two groups: group A, nonresponders vs. patients with a complete response, and group B, nonresponding and relapsing patients vs. patients with a sustained response; and 2) to establish a prognostic index using ROC curve analysis. The rate of sustained response was 6.5&#37; at the 24-month follow-up. The pretreatment characteristics with predictive value using ROC curves were as follows: in group A, age, GGT, serum ferritin, viral load, and grade and stage of the histological lesion; and in group B, known duration of infection, GPT, GGT, serum ferritin, viral load, and grade and stage of the histological lesion. In both group A and group B the positive predictive value (the probability of predicting an absence of response when the variable is present) was greater than the negative predictive value (mean: 84.3&#37; vs. 41.1&#37;, 99&#37; vs. 16.5&#37;, respectively). In group A, based on the prognostic index, the positive predictive value when three variables were present was 96&#37; and the sensitivity was 63.5&#37;, with the test being unequivocal in 6.5&#37;, whereas when four or five variables were present, the positive predictive value was 97&#37; and 100&#37; and the sensitivity was 40.5&#37; and 18&#37;, respectively. In group B, the positive predictive value when two variables were present was 100&#37; and the sensitivity was 87&#37;, whereas when three, four, five and six variables were present the sensitivity was between 73&#37; and 28&#37;. In group A, age, GGT and ferritin were the predictive variables independently associated with an absence of response, with a relative risk of 6.5, 4.8 and 3.1, respectively, whereas in group B we did not find variables independently associated with an absence of response. It was concluded that in patients with genotype 1, it is possible to predict the absence of response to IFN therapy with a high degree of reliability.
...
PMID:[ROC curve analysis of factors predictive of no response to interferon treatment in patients with chronic hepatitis C, genotype 1] 1087 38

This study assessed the activity and tolerability of an HIV-protease inhibitor, saquinavir, alone or in combination with zidovudine. A total of 92 previously untreated HIV-infected patients with CD4 cell counts < 300 cells/mm3 participated in a parallel, randomized double-blind study. Patients were randomized to receive one of five treatments, each three times a day: 600 mg of saquinavir; 200 mg of zidovudine; 75, 200 or 600 mg of saquinavir in combination with 200 mg of zidovudine. The primary treatment period was 16 weeks, with monthly extensions in patients who did not show major disease progression or toxicity. The main measures of the efficacy of therapy used were changes in CD4 cell counts and in the concentration of HIV-1 RNA in the plasma (as determined by quantitative polymerase chain reaction). The 600 mg dose of saquinavir in combination with zidovudine induced a 1.6 log (after 4 weeks) and a 0.7 log (after 16 weeks) median reduction in plasma RNA concentration; this reduction was greater than those seen in the other four treatment groups. The combination of 600 mg of saquinavir with zidovudine also resulted in a larger and more sustained improvement in the CD4 cell count than either saquinavir or zidovudine monotherapy or the other combination therapies. In the group receiving 200 mg of saquinavir in combination with zidovudine, the maximal median change in CD4 cell count occurred at week 2 (85 cells/mm3), and by week 16 had fallen to 15 cells/mm3. In the group receiving 600 mg of saquinavir plus zidovudine, the median change in CD4 cell count remained high for the 16-week period (median change of 48 cells/mm3 at week 2 and 61 cells/mm3 at week 16). Saquinavir was safe and very well tolerated, either alone or in combination with zidovudine. The incidence of adverse events was greater in the four groups receiving zidovudine therapy, and all the most commonly reported adverse events have previously been associated with zidovudine therapy. Few changes in laboratory values occurred during the study, except for known zidovudine-associated toxicities. The most frequent abnormalities were raised aspartate aminotransferase and alanine aminotransferase levels, depressed calcium levels, and abnormally high or low phosphate levels. Despite the low oral bioavailability of saquinavir, combined virological and immunological data show definite antiviral activity in vivo for the combination of saquinavir at 600 mg plus zidovudine at 200 mg (each three times daily). The combination of drugs with different mechanisms of action represents an advance in the treatment of HIV infection.
...
PMID:A randomized controlled trial of a protease inhibitor (saquinavir) in combination with zidovudine in previously untreated patients with advanced HIV infection. 1132 46

The activity of serum glutathione S-transferase (GST) was tested in bromobenzene-induced acute hepatotoxicity in mice. The data showed that a lot of small local necrosis in liver biopsy was observed and serum GST activity was increased after 2 h of treatment with bromobenzene (150 mg/kg i.p.) in mice. Serum alanine transaminase (ALT) activity was also gradually enhanced after 8 hours of treatment. The most obvious changes were at 16 hours of bromobenzene treatment, and serum GST activity was firstly restored to normal level after 24 hours of treatment. There were good positive correlations between serum GST, ALT, as well as serum GST and the changes on liver biopsy. Evaluating analysis of the diagnosis test showed that the sensitivity, specificity and accuracy was 89%, 75% and 82% in serum GST test, and 39%, 92% and 64% in serum ALT test respectively. The ROC work curve also demonstrated that serum GST was more sensitive and specific than serum ALT.
...
PMID:[Serum glutathione S-transferase in bromobenzene-induced acute hepato-toxicity in mice]. 1252 79


1 2 3 4 5 6 7 Next >>

---