458 research outputs found
Set-up for human sera MALDI profiling: the case of rhEPO treatment
No full textThe implementation of high-throughput technologies based on qualitative and quantitative methodologies for the characterization of complex protein mixtures is increasingly required in clinical laboratories. MALDI profiling is a robust and sensitive technology even though the serum high dynamic range imposes some limitations, preventing detection and identification of less abundant species. Efforts to increase the MALDI profiling detection ability are needed. A set-up has been performed for recombinant human erythropoietin (rhEPO) monitoring in serum analyzing the effects of two commercially available columns (MARS Hu7 and Hu14) for immunodepletion, and two matrices (α-cyano-4-hydroxycinnamic acid and 2’,4’-dihydroxyacetophenone) for spectra quality improvement.
Immunodepletion skills of both columns were determined by 2D-DIGE, which precisely revealed the efficacy of Hu14 in protein removal and in serum dynamic range decrement.
After optimization of the type of matrix and sample dilution, these new efficient conditions were used for serum profiling of ten healthy subjects before and after rhEPO treatment. The principal component analysis indicates that combination of Hu14 column and 2’,4’-dihydroxyacetophenone matrix increases data quality allowing to discriminate between treated and untreated samples, making serum MALDI profiling suitable for clinical monitoring of rhEPO
Reliability and validity of non-invasive determined haemoglobin mass and blood volumes
No full textIntroduction: The carbon monoxide (CO) rebreathing method used for the determination of haemoglobin mass (Hbmass) is associated with blood sample analysis (in this study: Radiometer ABL800). As an alternative hereto the aim of the present study was to evaluate the use of a portable and non-invasive CO pulse oximeter (Rad-57). Method: With simultaneous determination of CO in the circulation by ABL800 (%HbCO) and Rad-57 (SpCO), Hbmass and blood volume (BV) were determined in duplicates in 24 volunteers. Percentage of typical errors (%TE) within methods and linear correlations between the two procedures were computed. Results: Hbmass (Rad-57 = 798 ± 230 g; ABL800 = 781 ± 192 g) and BV (Rad-57 = 5700 ± 1373 ml; ABL800 = 5581 ± 1096 ml) were similar between methods. However, the %TE for Hbmass was higher (P 905 g and BV > 6193 ml. Conclusion: Assessment of SpCO by Rad-57 resulted in considerably less precise determinations of Hbmass and BV, especially for high values. Thus, non-invasive assessment of Hbmass and BV cannot be recommended for scientific purposes, but may nonetheless be useful in clinical settings
Reticulocyte profile in top-level alpine skiers during four consecutive competitive seasons
No full textThe role of reticulocytes (Ret) in sports medicine became clear when the count of immature erythrocytes was introduced in protocols used for anti-doping purposes. Because specific research regarding seasonal variations in Ret is lacking, we assessed Ret (and [Hb]) in top-level male and female skiers during four consecutive competitive seasons. A difference (P < 0.05) between males and females was found for [Hb] and Ret values: [Hb] was lower and Ret was higher in females. The difference was maintained across all four competitive seasons. Marked within-subject differences in [Hb], Ret and immature reticulocyte fraction values were noted; the within-subject variability was greater than the between-subject variability in both genders. For instance, a difference for Ret was consistently shown between first and second blood drawings, i.e. between basal value, before the start of training and competition, and the value at middle of season, when training workload was at highest level. Unlike Ret%, the analysis of variance showed significant changes in [Hb] values across competitive seasons for both genders. Comparison between consecutive seasons (e.g., 2005-2006 vs. 2006-2007) showed significant differences for both parameters. The behaviour of [Hb] and Ret during the various seasons was parallel in females, whereas a discrepancy existed in males. In general, inter-individual variability is quite high, thus, Ret and [Hb] modifications should be referred only to the single athlete. We confirm the validity of the use of Ret counts for anti-doping purposes
Seasonal variations of haematological parameters in athletes
No full textThe influence of training and competition workloads is crucial for evaluation of longitudinal haematological data in athletes. There are only a few papers on the variation of haematological parameters during long-lasting periods and, especially, during an entire competitive season. We summarized that some haematological parameters can be influenced by long-term training and competition periods. Haemoglobin (Hb) and haematocrit (Ht) are decreased during the more intense periods of training, throughout the season. In different sport disciplines, the decline of Hb ranges from 3 to 8% during the competition season, while the range of reticulocytes (Ret%) varies from 5 to 21%. Reticulocytes are also decreased after long periods of training and competitions, but their variation is not necessarily associated with that of Hb. The qualitative variations (trend of modifications) of haematological parameters are roughly independent of the sport discipline, but quantitatively (amount of modifications) dependent on sport discipline. The modifications are more evident in cycling, running, swimming than they are in football and rugby. The variations of haematological parameters within the same sport discipline are qualitatively concordant and quantitatively different among separate but consecutive competitive seasons. These findings are described in aerobic and team sports sportsmen. The definition of reliable reference ranges in sportsmen would only be possible by following the best laboratory practices. For antidoping purposes more studies investigating haematological modifications during the season are advisable
Seasonal variations of haematological parameters in athletes.
No full textThe influence of training and competition workloads is crucial for evaluation of longitudinal haematological data in athletes. There are only a few papers on the variation of haematological parameters during long-lasting periods and, especially, during an entire competitive season. We summarized that some haematological parameters can be influenced by long-term training and competition periods. Haemoglobin (Hb) and haematocrit (Ht) are decreased during the more intense periods of training, throughout the season. In different sport disciplines, the decline of Hb ranges from 3 to 8% during the competition season, while the range of reticulocytes (Ret%) varies from 5 to 21%. Reticulocytes are also decreased after long periods of training and competitions, but their variation is not necessarily associated with that of Hb. The qualitative variations (trend of modifications) of haematological parameters are roughly independent of the sport discipline, but quantitatively (amount of modifications) dependent on sport discipline. The modifications are more evident in cycling, running, swimming than they are in football and rugby. The variations of haematological parameters within the same sport discipline are qualitatively concordant and quantitatively different among separate but consecutive competitive seasons. These findings are described in aerobic and team sports sportsmen. The definition of reliable reference ranges in sportsmen would only be possible by following the best laboratory practices. For antidoping purposes more studies investigating haematological modifications during the season are advisable
Energetics of Underwater Swimming in Apnea
No full textPurpose: Dynamic apnea with fins (DYN) involves swimming the longest distance relying solely on the body’s oxygen and anaerobic energy stores. The energy cost per unit distance (C) is therefore an important determinant of DYN performance, yet it has never been measured. This study aimed to assess the C of DYN and its aerobic (EO2), anaerobic lactic (ELa) and alactic (EPCr) energy contributions. Methods: In a 50-m swimming pool, 22 freedivers (three female, ten using bi-fins, six the monofin, six both) performed a 50-m DYN, and seven also a 100-m DYN. Net C (above resting) was calculated from the O2 debt measured at emersion plus ELa (calculated from the blood lactate increase). In nine subjects (six of whom performed also the 100-m DYN), determination of hemoglobin mass and total lung capacity allowed the estimation of EO2 and, by subtraction, EPCr. Results: C was unchanged between the 100-m and the 50-m DYN (p=0.81) and resulted higher with bi-fins than with the monofin (7.4±2.2 vs. 5.5±1.6 J/kg/m, p=0.02) due to a higher O2 debt and ELa. DYN personal best correlated better with the distance swum per unit of EO2 at 50 m (R2=0.70) than with C (R2=0.25). From 50 m to 100 m, fractional EO2 decreased (58%±19% to 47%±13%, p=0.02), ELa increased (10%±5% to 21%±5%, p<0.001) and EPCr was unchanged (31%±20% to 32%±15%, p=0.83). Conclusions: The C of DYN seems compatible with published values for surface swimming with fins at the same speed. At 100 m, ELa and EPCr were disproportionately high for the exercise intensity, possibly due to a diving response. Sparing EO2 is at least as important as C in determining DYN performance
Long-term suicide risk of depression in the Lundby cohort 1947-1997 - severity and gender.
No full textObjective: The long-term suicide risk of depression was evaluated in a community sample by severity and gender. Method: The Lundby study is a prospective, longitudinal cohort study on a population consisting of 3563 subjects. In 1947-1997 medium or severe depression according to the Lundby diagnostic system were registered in 503 subjects. The same subjects were also diagnosed according to DSM-IV showing major depressive disorder (MDD) in 293 and depressive disorder not otherwise specified (DDNOS) in 131 subjects. Results: The overall long-term suicide risk varied from 5.6% to 6.8%. The long-term suicide risk was 3.1% for medium and 11.4% for severe 'Lundby depression', 3.7% for medium and 13.8% for severe MDD + DDNOS, 3.1% for medium and 13.7% for severe MDD. Severity and male sex were risk factors for suicide. Conclusion: Males with a severe depression showed a high long-term risk for suicide, around 20%
Setup for human sera MALDI profiling: The case of rhEPO treatment
No full textThe implementation of high-throughput technologies based on qualitative and quantitative methodologies for the characterization of complex protein mixtures is increasingly required in clinical laboratories. MALDI profiling is a robust and sensitive technology although the serum high dynamic range imposes a major limitation hampering the identification of less abundant species decreasing the quality of MALDI profiling. A setup to improve these parameters has been performed for recombinant human erythropoietin (rhEPO) monitoring in serum, analyzing the effects of two commercially available columns (MARS Hu7 and Hu14) for immunodepletion, and two matrices (α-cyano-4-hydroxycinnamic acid and 2′,4′-dihydroxyacetophenone) for peak quality improvement. The immunodepletion capability of both columns was determined by 2-D DIGE, which precisely revealed the efficacy of Hu14 in protein removal and the serum dynamic range decrement. In addition, the type of matrix, the sample dilution, and the efficacy of optimized parameters were used for serum profiling of ten healthy subjects before and after rhEPO treatment. The principal component analysis indicates that a combination of Hu14 column and 2′,4′-dihydroxyacetophenone matrix increases data quality allowing the discrimination between treated and untreated samples, making serum MALDI profiling suitable for clinical monitoring of rhEP
Does it make sense to do repeated surveys? - the Lundby Study, 1947-1997.
No full textObjective: To describe the Lundby Study and the difficulties in doing repeated surveys. Method: Best-estimate consensus diagnoses have been used since 1957 together with DSM-IV and ICD-10 in 1997. Results: The Lundby population consisting of 3563 probands was investigated in 1947, 1957 and 1972. Sufficient information was available for 98-99%. In 1997-2000 a fourth field investigation was carried out. Attrition rate for the interviews was 13% (238/1797). About 36% (1030/2827) had died between 1972 and 1997, but data from registers, case notes and key-informants for the period 1972 and 1997 completed the information for 94% (2659/2827). The population has followed the same pattern of development as many rural populations in Sweden since the 1940s. Multiple sources of information are preferable in longitudinal studies in order to tackle the problem of changing diagnostic systems. Conclusion: Low attrition rates over 50 years and reasonable diagnostic uniformity make comparisons over time justifiabl
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