Sepsis induced by cecal ligation and perforation (CLP) alters nucleotidase activities in platelets of rats.

Sepsis is a potentially lethal condition, and it is associated with platelet alterations. The present study sought to investigate the activity of ecto-nucleoside triphosphate diphosphohydrolase (E-NTPDase), E-5'-nucleotidase, and ecto-adenosine deaminase (E-ADA) in the platelets of rats that were induced with sepsis. Male Wistar rats were divided into three groups of ten animals each: a negative control group (normal; NC); a group that underwent surgical procedures (sham); and a group that underwent cecal ligation and perforation (CLP). The induction of sepsis was confirmed by bacteremia, and the causative pathogen identified was Escherichia coli. Hematological parameters showed leukocytosis and thrombocytopenia in animals in the septic group. The results also revealed that there were significant (p < 0.05) increases in adenosine triphosphate (ATP) and adenosine monophosphate (AMP) hydrolyses, and in the deamination of adenosine in the CLP group compared to the sham and control groups. Conversely, ADP hydrolysis was significantly decreased (p < 0.05) in the CLP group compared to the sham and control groups. Purine levels were analyzed by high-performance liquid chromatography (HPLC) in serum samples from control, sham, and CLP groups. Increased concentrations of ATP, adenosine, and inosine were found in the CLP group compared to the sham and control groups. Conversely, the concentrations of ADP and AMP in the CPL group were not significantly altered. We suggest that alterations in hematological parameters, nucleotide hydrolysis in platelets, and nucleotide concentrations in serum samples of rats with induced sepsis may be related to thromboembolic events.

Hba(1c) as a tool for the diagnosis of type 2 diabetes: comparison with fasting glucose.

BACKGROUND: Glycated hemoglobin (HbA(1c)) has been proposed for the diagnosis of diabetes. However, several countries have not incorporated its use for this purpose yet and there is no consensus on a suitable cut-off point of HbA(1c) for the diagnosis of diabetes. Thus, the aim of this study was to evaluate the diagnostic characteristics of HbA(1c) and fasting plasma glucose (FPG) for the assessment of type 2 diabetes. METHODS: FPG, HbA(1c), and creatinine levels were assessed in 47 patients with type 2 diabetes and 46 healthy controls. RESULTS: The areas under the curve for HbA(1c) > or = 6.5% and FPG > or = 7.0 mmol/L were 0.97 and 0.92, respectively. HbA(1c). has a slightly higher ability to discriminate type 2 diabetes compared with FPG. The association between HbA(1c) and type 2 diabetes was independent of gender, age, hypertension, smoking, and body mass index. CONCLUSIONS: HbA(1c) was able to be used for the diagnosis of type 2 diabetes.

Effect of temperature on albumin cobalt binding and its influence on ischemia-modified albumin levels in patients with suspected acute coronary syndrome.

BACKGROUND: Ischemia-modified albumin (IMA) has been shown to be a rapidly rising and sensitive biochemical marker especially for the diagnosis of myocardial ischemia. The aim of this study was to evaluate the influence of temperature on the capacity of cobalt binding to human albumin and the influence of this variable on IMA measurement. METHODS: The following temperatures of incubation were tested for human albumin standard 25 degrees C, 28 degrees C, 31 degrees C, 34 degrees C, and 37 degrees C and for patients with suspected acute coronary syndrome, room temperature and 37 degrees C. IMA was measured by cobalt-albumin binding assay. RESULTS: There was a strong positive correlation (r = 0.98, p < 0.001) between IMA and the assay temperatures. IMA levels were 0.68 +/- 0.25 absorbance units (ABSU) at room temperature and 0.92 +/- 0.33 ABSU (p < 0.001) at 37 degrees C in the study participants. CONCLUSIONS: IMA values were influenced by the assay temperature.

Enzymes that hydrolyze adenine nucleotides in lymphocytes and platelets of immunosuppressed rats.

NTPDase (EC 3.6.1.5) is an enzyme that hydrolyzes extracellular nucleoside tri-and/ or diphosphates to form ATP, which can serve as a substrate for ecto-5'- nucleotidase (EC 3.1.3.5), releasing adenosine, an inhibitor of platelet aggregation and an immunosuppressant agent. In this study, the activity of enzymes that hydrolyze adenine nucleotides was investigated in lymphocytes and platelets of immunosuppressed rats. NTPDase and ecto-5'-nucleotidase activities were determined by colorimetric assay with quantification of the inorganic phosphate released. A significant increase in NTPDase activity was observed in lymphocytes (about 30% in ATP hydrolysis and 80% in ADP hydrolysis, at p<0.05 and p<0.01, respectively). In platelets, there was a significant increase in 5'-nucleotidase activity in immunosuppressed rats (p<0.01) when compared with controls. These results suggest that the hydrolysis of adenine nucleotides is modified in the immunosuppressed state, possibly to compensate for alterations that occur and to avoid the adverse effects of therapy.