1,721,431 research outputs found
State of the art of preanalysis in laboratories in Italy performing endocrinological tests
No full textWe conducted an inquiry among Italian laboratories regarding the preanalytical phase for endocrinological tests. The form presented two questions: number of analyses per year and use of closed or open system for blood drawing. The laboratories were asked to insert the hormones' names in some boxes representing different materials for endocrinological tests, namely serum from plain tubes and from gel separator tubes, plasma from K3EDTA, Na2EDTA, lithium heparin with or without gel separator, sodium citrate, sodium fluoride and potassium oxalate, and citric acid-citrate-dextrose (ACD), and also the particular mode of storage of specimen, as addition of antiproteolytic substances and use of iced water. The analytes' list included the most common endocrinological assays. The data collected indicate that traditional, syringe-based systems are still widely used in Italy, particularly in private and small and medium-sized public laboratories. Serum is the most often used material for endocrinological tests. A very important finding was the use of gel separator tubes, wider than plan tubes, for obtaining serum. Finally, the laboratories demonstrated very good attention to the preanalytical phase, as judged from particular storage for some delicate analytes
Reticulocytes in sports medicine
No full textReticulocytes are the transitional cells from erythroblasts to mature erythrocytes. Reticulocytes are present in blood for a period of 1-4 days and can be recognized by staining with supravital dyes, such as new methylene blue, or fluorescent markers, which couple residual nucleic acid molecules, a hallmark of the immature forms of erythrocytes. Although reticulocytes could be counted through a microscope (there is a standard of International Committee for Standardisation in Haematology for manual counting), this method is reported to be time consuming, inaccurate and imprecise. The integration of the reticulocyte count in automated haematology systems allowed the widespread use of these parameters, although the lack of calibration material and different markers, technologies and software used in automated systems could engender discrepancies among data obtained from different analytical systems.The importance of reticulocytes in sports medicine derives from their sensitivity, the highest among haematology parameters, in identifying the bone marrow stimulation, especially when recombinant human erythropoietin is fraudulently used. Automated systems are also able to supply information on volume, density and the haemoglobin content of reticulocytes.Some of the related parameters are also used in algorithms for identifying abnormal stimulation of bone marrow as reticulocytes haematocrit. The pre-analytical variability of reticulocytes (transportation, storage, biological variability) should be taken into account in sports medicine also. Reticulocytes remain stable for almost 24 hours at 4 degrees C from blood drawing, they are affected by transportation, and biological variability is not high in general. It could be remarked, however, that the intra-individual variability is high when compared with other haematological parameters such as haemoglobin and haematocrit. The intervals of data reported in athletes are very similar to reference intervals characterizing the general population.The reticulocyte count shows some modifications after training and during the competition season. The variability induced by exercise cannot be overlooked since the so-called haematological passport, a personal athlete's document in which haemoglobin and other parameters are registered, may be introduced by sports federations. Exposure to naturally high altitude and 'living high-training low' programmes determined contentious results on reticulocytes. Simulated high altitude induced by intermittent hypobaric hypoxia does not modify reticulocytes, despite an increase in erythropoietin serum concentration. The variability among athletes competing in different sport disciplines is apparently limited. The knowledge of the behaviour of reticulocytes in training and competitions is crucial for defining their role in an antidoping control context. It is important for sport physicians and clinical pathologists to know the reticulocyte variability in the general population and in athletes, the pre-analytical warnings, the different methodologies for counting reticulocytes and the derived parameters automatically available, and, finally, the possible influence of training, competitions, type of sport and altitude
Interferences by cryoglobulins and cold agglutinins with blood cell measurement on coulter counter
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Relation between values of haemoglobin, erythrocytes and reticulocytes and body mass index in elite athletes of different sports disciplines
No full textRelation between body mass index and serum aminotransferases concentrations in professional athletes
No full textReference intervals commonly used for evaluating and interpreting laboratory values obtained in athletes are the same used in the general population. Aminotransferases (aspartate aminotransferase [AST], and alanine aminotransferase [ALT]) are commonly analyzed in serum for evaluating hepatic function. Some studies in the general population and in blood donors testified that ALT concentrations clearly correlated with weight and body mass
Effect on sport hemolysis of cold water leg immersion in athletes after training sessions
No full textThe principal source of increased turnover of erythrocytes in athletes is sport hemolysis, the intravascular hemolysis that characteristically occurs with athletic performance in sport. The use of the parameter mean sphered cell volume (MSCV), automatically measured by means of the Coulter LH750, could be useful for diagnosing the presence of sport hemolysis. We studied the behavior of MSCV and mean corpuscular volume (MCV) in 30 top-level rugby players who underwent a heavy training session followed by 3 different recovery methods, administered to 3 subgroups of 10 athletes. We tested the use of active recovery consisting of cold water (5 degrees C) immersion of legs for 10 minutes either before (n = 10) or after (n = 10) cycling at 180 W for 10 minutes. In the whole group of athletes, measurements performed at rest and after training session and recovery showed no differences in MCV and MSCV values. The difference between MCV and MSCV was significant in the whole group and in the subgroup performing passive recovery, whereas the difference was not significant in the subgroups performing active recovery. This finding indicates that the use of active recovery in the top-level rugby players prevented the modifications of erythrocyte volume and shape. We outline that the values of the difference between MCV and MSCV was significantly modified in the whole group but the variations were not significant in the active recovery subgroups. The use of an index of erythrocyte shape modification (MCV - MSCV) can be very useful for evaluating sport hemolysis
Free testosterone/cortisol ratio in soccer: usefulness of a categorization of values
No full textThe free testosterone:cortisol ratio (FTCR) is widely used for studying and preventing overtraining syndrome in various sports. The use of FTCR for following overtraining syndrome was proposed originally with two approaches: FTCR lower than 0.35x10(-3), calculated on free testosterone (FT) in nanomoles per liter (nmol/L) and on cortisol (C) in micromoles per liter (mmole/L) or a decrease of the ratio of 30% or more in comparison with the previous value. In our experience, the use of an absolute value as a threshold is not useful, whereas the evaluation of the concentrations of hormones and their ratio in comparison with previous ones is more useful. These classical approaches are not, however, sufficient to describe the various possible physiological modifications linked to training excess and/or incomplete recovery
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