1,721,246 research outputs found
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
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
COVID-19: which lessons have we learned?
No full textCoronavirus disease 2019 (COVID-19), the worst infectious disease that has affected humanity over the past century, is still causing dramatic derangements of healthcare, society and economy, so that nothing will be the same as before. Several months after the World Health Organization (WHO) has declared COVID-19 a pandemic, many enquiries remain unanswered. The first and foremost is, perhaps, if (and when) we will be able to completely eradicate SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2), and life could optimistically return to a “new” normal. The most likely answer is “probably no”, at least for several months (years) to come. We shall not be really surprised by this, since the influenza virus H1N1, which caused the dramatic Spanish flu pandemic nearly 100 years ago, is still among us and kills several people during every new outbreak, with a death rate especially high in the older and sick population (i.e., between 0.1-1.0%). Therefore, given for granted that we will need to learn to live with this new (corona)virus for quite a long time, we shall need to think out of the box and envisage strategies aimed to make the healthcare (system) more efficient to withstand the considerable clinical, societal and economic impact of COVID-19. This would actually encompass a complete revolution of the entire system of care, including community-based medicine, hospital medicine, in vitro diagnostic testing and rehabilitation medicine, according to a novel, patient-centered system of care, based on the peculiar clinical and organizational aspects characterizing the ongoing SARS-CoV-2 pandemic
Effects of sample matrix and storage conditions on full-length visfatin measurement in blood
No full textPreanalytical phase of sport biochemistry and haematology
No full textBiochemistry and haematology are more and more important and sometimes crucial in sport medicine for diagnosing, controlling and preventing purposes. The analytical process and the global laboratory quality are heavily influenced by the pre-analytical phase, including biological material collection, identification, storage and transport of the specimen, preparation for analyses of the specimen through centrifugation, freezing and thawing, aliquoting and sampling. The increasing interest of sport biochemistry should be linked to a knowledge of principal problems and pitfalls in the preanalytical phase of various parameters, commonly used in following training, diet, and performances of athletes, to avoid misinterpretation of data and to improve usefulness of biochemical investigations. We prepared a practical review of preanalytical aspects of principal analyses applied to the athletes. We include the choice of anticoagulant and its limits for haematological tests, the preparation and manipulation of specimens for hormonological investigation, especially for labile molecules, and for cardiac markers, lactate, cytokines, micronutrients, antioxidant molecules. Preanalytical phase of specimens different from blood are also showed, including urine and saliva, and some aspects of preparation of materials to be analyzed with molecular biology technology are treated. Stability of some analytes, when the parameter is fundamental for the clinical usefulness of the results, is supplied. Preparation of the subjects, however, including the possible influence of physical exercise and biological rythms on the biochemical and haematological parameters, are not listed
Comments on Delanghe and Joyner's Editorial "Testing for recombinant human erythropoietin"
No full textFree testosterone/cortisol ratio in soccer: usefulness of a categorization of values
No full textAim. The 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 (mu mole/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. Methods. We collected samples from 32 professional soccer players of an Italian First Division team, during the period July 2001-July 2003. We analyzed the values of 21 athletes during the season 2001-2002 and of 11 athletes during the season 2002-2003 (6 out of 11 were examined also during the previous one) always present when the 4 (first season) or 5 (second season) blood drawings have been performed. We applied an original, pragmatic and easy-to-use classification of FTCR values, in association with classical interpretations based on decreases of the values in comparison with previous athlete's result. Results. We used the traditional approaches in two consecutive seasons in a professional soccer team: the evaluation of the decrease >30% of the parameter in comparison with the previous value or with the basal (preseason) value are shown. The statistical differences between the FTCR values of the six athletes followed in both seasons were not significant. Conclusions. The classification method we propose is advantageous in comparison with traditional interpretative schemes, because identify different risk categories, stratifying the interval between the values 0.35-0.8
The impact of preanalytical variability in clinical trials: are we underestimating the issue?
No full textThe impact of preanalytical variability in clinical trials: are we underestimating the issue
Exercise-related increase of cardiac troponin release in sports: An apparent paradox finally elucidated?
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