[The effect of corifollitropin alfa on in vitro fertilization-ICSI patients with previous failure with an FSH/HMG protocol: Preliminary report in Mexico]. / Efecto de la corifolitropina alfa en pacientes de fertilización in vitro-ICSI con falla previa en un protocolo de FSH/HMG: experiencia preliminar en México.

BACKGROUND: The daily application of drugs, often in high doses, is a factor of stress for the infertile couple. During the last decade corifollitropin alpha has allowed a friendlier scheme comparable to traditional protocols (rFSH-HMG) results. OBJECTIVE: To compare the results of corifollitropin alpha in patients with a previous cycle of IVF-ICSI with traditional scheme ovarian stimulation. MATERIALS AND METHODS: Observational, retrospective cohort study type that infertile couples were included. RESULTS: No significant differences in the dose used HFRS (2023U/ total ± 712 vs 636 U/total ± 307) and serum estradiol day shooting HGCr (1972 pg/dL vs 1107 ± 1152 pg/dL ± 775). A higher pregnancy rate was found corifollitropin alpha perhaps because it was a second attempt at in vitro fertilization. CONCLUSIONS: Reproductive outcomes in a cycle of ovarian stimulation with corifollitropin are comparable with the results of a traditional ovarian stimulation cycle. It is important to broaden the experience of the drug indication in Mexican patients.

Effect of cycling competition type on effort based on heart rate and session rating of perceived exertion.

AIM: The aim of this study was to compare the exercise intensity and competition load during Time Trial (TT), Flat (FL), Medium Mountain (MM) and High Mountain (HM) stages based heart rate (HR) and session rating of perceived exertion (RPE). METHODS: We monitored both HR and RPE of 12 professional cyclists during two consecutive 21-day cycling races (Vuelta a España) in order to analyze the exercise intensity and competition load (TRIMPHR and TRIMPRPE). RESULTS: The highest (P<0.05) mean HR was found in TT (169±2 bpm) versus those observed in FL (135±1 bpm), MM (139±3 bpm), HM (143±1 bpm). However, higher (P<0.05) session RPE were found in HM (7.3±0.2) and MM (7.0±0.3) vs. TT (5.5±0.4) and FL (4.6±0.2). TRIMPHR and TRIMPRPE increased significantly (P<0.05) in the following order: TT, FL, MM and HM. The greatest (P<0.05) TRIMPHR·km-1 and TRIMPRPE·km-1 were obtained in TT (~4 units) and HM (~12 units), respectively. We found significant (p<0.001) correlations between TRIMPHR and TRIMPRPE in TT (r=0.62), FL (r=0.74), MM (r=0.89) and HM (r=0.78). CONCLUSION: In conclusion, professional cycling is a highly demanding sport which exercise intensity and competition load varied according to the type of stages. The session RPE method is a valid estimate of internal load during different cycling stage categories.

Physical and thermal strain of firefighters according to the firefighting tactics used to suppress wildfires.

The aim of this study was to analyse the physiological strain of firefighters, using heart rate (HR) and core temperature, during real wildfire suppression according to the type of attack performed (direct, indirect or mixed). Three intensity zones were established according to the HR corresponding to the ventilatory threshold (VT) and respiratory compensation threshold (RCT): zone 1, RCT. The exercise workload (training impulse (TRIMP)), the physiological strain index (PSI) and the cumulative heat strain index(CHSI) were calculated using the time spent in each zone, and the HR and core temperature, respectively. Significantly higher mean HR, time spent in Z2 and Z3 and TRIMP h(-1) were found in direct and mixed versus indirect attacks. The highest PSI and CHSI were observed in the direct attack. In conclusion, exercise strain and combined thermal strain, but not core temperature during wildfire suppression, are related to the type of attack performed. STATEMENT OF RELEVANCE: Our findings demonstrated that wildfire firefighting is associated with high physiological demands, which vary significantly depending on the tactics chosen for performing the task. These results should be kept in mind when planning programmes to improve wildland firefighters' physical fitness, which will allow improvement in their performance.

Workload demands in professional multi-stage cycling races of varying duration.

OBJECTIVE: To analyse and compare the workload exerted by professional cyclists in 5-day, 8-day and 21-day stage races (5-SR, 8-SR, 21-SR). METHODS: The study subjects were 30 professional cyclists competing in 10 5-SR, 5 8-SR and 5 21-SR. Heart rate (HR) was measured during the races and categorised into three intensity zones: Z1 (below the ventilatory threshold (VT)), Z2 (between VT and the respiratory compensation threshold (RCT)) and Z3 (above RCT). The training impulse (TRIMP) was calculated by multiplying the sum of the time spent in each zone by 1, 2 and 3, respectively. Monotony (average TRIMP/SD) and strain (total TRIMPxmonotony) were also calculated for each race type. RESULTS: The average time spent in Z3 during each stage was significantly (p<0.05) higher for 5-SR ( approximately 31 min) and 8-SR ( approximately 28 min) than for 21-SR ( approximately 14 min). Daily TRIMP values in 5-SR ( approximately 400) and 8-SR ( approximately 395) were also higher than in 21-SR ( approximately 370). Monotony was similar across races ( approximately 3) but strain was about three times higher for 21-SR than for 5-SR and 8-SR. CONCLUSIONS: The cyclists' effort by stage was less for 21-SR than for 5-SR and 8-SR. Competition strain and monotony accumulated during longer races influence the choice of strategies adopted by cyclists. It is likely that the intensity of each stage is modulated by total race duration, with longer races averaging the lowest daily workload.

Changes in mucosal and humoral atopic-related markers and immunoglobulins in elite cyclists participating in the Vuelta a España.

Atopic-related factors, humoral and mucosal immunoglobulins (Ig), and cortisol were measured in 17 professional cyclists competing in the 2003 Vuelta a España (a three-week multi-stage race). Venous blood and saliva samples were obtained the morning before the start of the race (T0), on the first rest day after 10 days of racing (T1), and before the start of the last stage after 21 days of racing (T2). Atopic-related factors, IgE, eosinophil cationic protein (ECP), and eosinophils, were significantly altered during the race. Serum IgE (T1: + 10 %) and ECP (salivary, T1: 113 % and serum, T2: 155 %) were significantly increased, while eosinophils (T1: - 32 %, T2: - 55 %) were significantly lower, than pre-race levels. Salivary sIgA secretion rate was significantly decreased at T2 (- 36 %). Pearson product-moment correlations revealed a modest correlation between salivary sIgA and salivary ECP (T1: r = 0.30; T2: r = 0.48; p < 0.01). Serum IgM, total IgG, IgG1, IgG2, IgA levels, at T1 and T2, and cortisol at T2, were significantly lower than pre-race levels. In conclusion, the elevation in IgE and ECP suggests an up-regulation of atopic-related factors in professional cyclists participating in the Vuelta a España. The correlation between salivary sIgA and salivary ECP indicates a role for sIgA in mediating mucosal inflammation. The alterations in Ig levels may indicate Ig isotype switching. An increasing state of hormonal fatigue may have influenced the observed immune alterations.

The validation of a new method that measures contact and flight times during vertical jump.

The aim of this study was to design and validate a vertical jump assessing system based on flight time measurements. Hence, the first phase of this study consisted of programming the software SportJumpv-1.0 and adapting a contact mat and a computer mouse in order to record the flight and contact times of a jump test. In the second phase, 9 subjects made 12 maximal and submaximal vertical single and rebound jumps. Thus 108 flight times and 36 contact times were simultaneously obtained with five different systems: ErgoJump Bosco System (PS), SportJump-v1.0 (SJ), Force Plate (FP), High-speed camera (HSC), and a Led (LED) filmed with a high-speed camera; FP was considered as the reference system. No significant differences were found either between SJ and LED, or between FP and HSC systems. SJ and LED overestimate flight time (9 ms and p < 0.001) and underestimate contact time in respect to FP values. PS underestimates flight time regarding FP values (4 ms and p < 0.01). In spite of the differences obtained between the systems, the errors found are constant. Those slightly depend on the subject's body mass for the systems that are connected to a contact mat. A high correlation between all of them was obtained (r approximately 1 and p < 0.001). The SJ system was validated for an accuracy of 500 Hz, and it was shown to be a useful tool in measuring flight and contact times during jumping. The differences and correlations found between the five systems show that it is necessary to take into account which system is being used when analyzing vertical jump performance.

Mutations in the hereditary haemochromatosis gene HFE in professional endurance athletes.

BACKGROUND: Hereditary haemochromatosis, a disease that affects iron metabolism, progresses with a greater or lesser tendency to induce iron overload, possibly leading to severe organ dysfunction. Most elite endurance athletes take iron supplements during their active sporting life, which could aggravate this condition. OBJECTIVE: To determine the prevalence and discuss potential clinical implications of mutations of HFE (the gene responsible for hereditary haemochromatosis) in endurance athletes. METHODS: Basal concentrations of iron, ferritin, and transferrin and transferrin saturation were determined in the period before competition in 65 highly trained athletes. Possible mutations in the HFE gene were evaluated in each subject by extracting genomic DNA from peripheral blood. The restriction enzymes SnaBI and BclI were used to detect the mutations 845G-->A (C282Y) and 187C-->G (H63D). RESULTS: Our findings indicate a high prevalence of HFE gene mutations in this population (49.2%) compared with sedentary controls (33.5%). No association was detected in the athletes between mutations and blood iron markers. CONCLUSIONS: The findings support the need to assess regularly iron stores in elite endurance athletes.

Physical exercise and improvement of liver oxidative metabolism in the elderly.

Drug metabolizing capacity is generally reduced in the elderly, and physical exercise has been reported to increase drug oxidative metabolism. The purpose of this investigation was to study the effects of engagement in a program of regular physical exercise on the clearance and metabolite excretion of antipyrine, a marker of oxidative metabolism, in elderly subjects. The saliva clearance of antipyrine and the production clearances of antipyrine metabolites were studied in 37 elderly women (mean age 66 years). Subjects attended 60-min sessions three times a week for 12 weeks. Each session consisted of both aerobic (training of cardiorespiratory capacity) and nonaerobic (training of muscular strength/endurance and flexibility/coordination) exercises performed at 50-75% of maximum oxygen uptake. Antipyrine was administered orally and pharmacokinetic parameters were obtained from saliva and urine samples. After 3 months of participation in the exercise program, salivary antipyrine clearance was significantly increased by 17% mean (SEM) 0.42 (0.02) vs 0.36 (0.02) ml/min/kg; P < 0.05) and the half-life of antipyrine was significantly reduced by 18% (17.9 (1.1) vs 22.3 (1.3) h; P < 0.05). No significant change with exercise was observed in the renal clearance of antipyrine or in the norantipyrine formation clearance, but significant increases were found for hydroxymethylantipyrine [42 (5) vs 32 (4) microl/kg/min; P < 0.05; +31%] and 4-hydroxyantipyrine [243 (18) vs 194 (17) microl/kg/min; P < 0.05; +25%] formation clearances. These findings indicate that regular exercise leads to increased disposition of antipyrine in the elderly and that the main metabolic pathways of the compound are changed differentially.

Changes in metabolism and urinary excretion of antipyrine induced by aerobic conditioning.

BACKGROUND: Physical conditioning has been reported to increase liver oxidative metabolism determined by antipyrine clearance. The purpose of this investigation was to study effects of aerobic conditioning on the different metabolic pathways of antipyrine by comparing the production clearances of antipyrine metabolites. PARTICIPANT: volunteers not engaged in the systematic practice of any sport (n = 14) were compared with aerobically-conditioned subjects (n = 14) (long distance runners, defined as men running > 80 km/week). INTERVENTIONS: antipyrine was administered orally. Saliva samples were collected under basal conditions and at 8, 16, 24, 32 and 40 hrs following antipyrine administration. Urine was collected for 24 hrs after antipyrine ingestion. MEASURES: endurance performance was expressed by the maximal oxygen uptake (VO2max), the ventilatory threshold and the 4 mM.l-1 lactate threshold (OBLA). Antipyrine pharmacokinetic parameters (antipyrine clearance and half-live) were obtained from saliva samples by the standard multiple-sample method. RESULTS: VO2max, ventilatory threshold and OBLA were higher in trained than in control subjects (+32%, +16% and +74%, respectively). Salivary antipyrine clearance was higher, whether or not this variable was corrected for weight (+26% and +38%, respectively), and antipyrine half-life was significantly reduced (-31%) in runners. There was no significant change with training in the renal clearance of antipyrine or in the norantipyrine (NORA) formation clearance but significant increases were observed in hydroxymethylantipyrine (HMA) and 4-hydroxyantipyrine (OHA) formation clearances (+42 and +37%, respectively). CONCLUSIONS: The findings indicate that aerobic conditioning leads to increased disposition of antipyrine and that the main metabolic pathways of the compound are changed differently.

The effect of physical conditioning on antipyrine clearance.

The effects of physical conditioning on antipyrine clearance were studied in two groups of subjects. Healthy men not engaged in the systematic practice of any sport were compared with endurance runners (defined as men running > 80 km/week). Studies were carried out at three different periods of the annual plan training at 4-month intervals. Antipyrine was administered orally and pharmacokinetic parameters were obtained from saliva samples by the multiple-sample method. Endurance performance, expressed in terms of the maximal oxygen uptake (VO2max), the ventilatory threshold and the 4-mM x l(-1) lactate threshold (OBLA), was higher in trained than in control subjects at each of the three periods. Antipyrine clearance was also significantly elevated and antipyrine half-life reduced in runners during all periods. No significant difference in VO2max or antipyrine clearance was found between the various periods in either trained or control subjects. Both ventilatory threshold and OBLA increased significantly along the training period in conditioned subjects. Significant correlations were found between antipyrine clearance and VO2max, ventilatory threshold and OBLA. In summary, these results indicate an association between aerobic conditioning and increased hepatic oxidative metabolism of low-clearance drugs.

Effects of long-distance running on serum bilirubin.

This study was undertaken to determine the effects of long-distance running on serum bilirubin fractions. Thirteen male ultramarathon runners participating in a 100-km race volunteered for the study. Venous blood samples were obtained shortly before and immediately after the race. Decreased serum haptoglobin levels (-66%) indicated the presence of hemolysis. After accounting for plasma-volume loss, significant post-race increases were found for creatine kinase (+20-fold), creatine kinase-MB (+252%), alanine aminotransferase (+42%), aspartate aminotransferase (+193%), gammaglutamyl transpeptidase (+56%), and glutamate dehydrogenase (+58%) serum activities, suggesting that running causes alterations of both muscle and liver tissues. Serum concentration of total bilirubin was significantly elevated (+106%) following the race, with changes corresponding to both unconjugated (+96%) and conjugated esters (+283%) of the pigment and significant increases in the ratio of esterified to total bilirubin. Our data show that long-distance running causes increases in the different serum bilirubin fractions which can be accounted for both hemolysis and hepatic disturbances.

Effects of aerobic and anaerobic physical conditioning on fibrinolysis.

The effects of aerobic and anaerobic physical conditioning on fibrinolysis were studied before and immediately after physical exercise. Moderately active controls (group A) were compared with aerobically- (group B) or anaerobically-conditioned (group C) subjects. Comparison of the resting parameters revealed that FgDP were significantly higher in group B as a compared to groups A and C. FbDP did not significantly differ between groups B and C and were significantly lower in group A. t-PA antigen and PAI antigen did not significantly differ between the three groups, but t-PA activity was elevated and PAI activity and t-PA/PAI complexes were reduced in group B. Following a maximal exercise test on the treadmill both FbDP and FgDP were significantly increased in all groups, although values for FbDP in group B and values for FgDP in group C reached a higher level than in group A. t-PA antigen and t-PA activity were also increased in the three groups. PAI activity was significantly reduced in groups A and C. t-PA/PAI complexes were significantly enhanced in all cases, but increased to a lower degree in group B. These results indicate that both aerobic and anaerobic physical conditioning induce activation of the fibrinolytic system.

Effects of oral contraceptives on fibrinolytic response to exercise.

In this study the influence of low-dose oral contraceptives (OC) on the different components of the fibrinolytic system before and immediately after maximal exercise was examined in a group of 18 moderately active women. Nine women using OC and nine control women performed a maximal effort treadmill protocol. Comparison of the resting parameters revealed higher plasma FbDP, plasminogen, alpha 2-antiplasmin and protein C concentrations, and lower PAI activity in the OC group. No differences were observed in plasma concentrations of t-PA antigen, t-PA activity, PAI antigen, antithrombin III, and protein S. Acute maximal exercise resulted in significant increases in t-PA antigen, t-PA activity, t-PA/PAI complexes, and FbDP in both groups of subjects, while PAI activity was reduced. No significant differences were found for the change in those parameters between control and OC users. Exercise induced no variation in any of the groups for PAI antigen, alpha 2-antiplasmin, plasminogen, protein C, or protein S. Our data suggest that changes in the fibrinolytic system induced by physical exercise are not affected by oral contraceptives.

Impairment of bile secretion induced by exhaustive exercise in the rat. Protective effects of S-adenosyl-L-methionine.

The effects of strenuous exercise on the mechanisms of bile formation were studied in rats. Animals (n = 8) were exercised to exhaustion in a rodent treadmill at a speed of 24 m/min and a 12% slope. Hepatic glutathione concentration was significantly reduced (-40%) and liver malondialdehyde content significantly increased (+37%) when compared to sedentary controls (n = 6). Both serum alkaline phosphatase level and bile acid concentration were significantly higher in runners (+81% and +85%). Bile flow and the biliary secretion of bile acids were significantly reduced both in basal conditions and following an i.v. taurocholate infusion (0.5 mumol/min/100 g body wt). Biliary glutathione secretion was also significantly decreased following exercise. Cholestasis was caused by an impairment of both bile acid-dependent (BADF) and bile acid-independent fraction (BAIF) of bile flow (-25% and -29% respectively). Exercise caused a delay in the peak appearance time and a reduced biliary secretion of horseradish peroxidase, suggesting alterations in the functional integrity of the cytoskeleton. To test the protective effects of S-adenosyl-L-methionine (SAMe), rats received the drug for ten days at a daily dose of 8 mg/kg i.p. SAMe administration prevented hepatic glutathione depletion due to exercise, normalizing both bile flow and bile acid as well as glutathione secretion. Our results suggest that both glutathione depletion and alterations in fluidity and composition of hepatocyte membranes could contribute to the development of exercise-induced cholestasis.

Changes in the fibrinolytic system associated with physical conditioning.

The effects of physical conditioning on plasma fibrinolytic activity were studied in two groups of subjects. Volunteers not engaged in any sport were compared with individuals having been subjected to aerobic conditioning (middle-distance runners, defined as men running more than 80 km per week). Plasma concentrations of the different components of the fibrinolytic system were evaluated before and immediately after a maximal effort treadmill protocol. Comparison of the resting parameters revealed that under basal conditions for plasma concentrations of plasminogen, fibrinogen, alpha 2-antiplasmin, protein C and protein S there were no differences between the two groups. Concentrations of the fibrin degradation products (FbDP) and fibrinogen degradation products (FgDP) were significantly higher in the runners than in the control group, indicating an increased fibrinolytic potential that seemed to be a consequence of the reduced formation of tissue plasminogen activator-plasminogen activator inhibitor (t-PA-PAI) complexes. Acute maximal exercise resulted in pronounced fibrinolysis, evidenced by the elevation of FbDP and FgDP concentrations, in both groups of subjects. The acceleration of the fibrinolytic activity was larger in conditioned individuals, which could be accounted for by a higher t-PA release and reduced formation of t-PA-PAI complexes when compared to the untrained subjects.

Changes in the biliary excretion of organic anions following exhaustive exercise in rats.

The effect of exhaustive exercise on the hepatobiliary transport of organic anions was investigated in rats. Animals were run on a rodent treadmill at 24 m/min up a 12% grade (152 +/- 15 min). Exercise resulted in significant hypoglycaemia (-46%) and increased plasma levels of lactate (+12%), together with a marked reduction of glycogen concentration in the liver (-72%). When bromosulphthalein was administered i.v., its maximal biliary excretion (Tm) was significantly reduced (-30%), and plasma and liver concentrations of the dye were increased (+31% and +56%, respectively). The decrease corresponded both to the excretion of the conjugated and unconjugated dye (-30% and -33%, respectively). Cytosolic glutathione S-transferase activity in the liver was not affected by exercise, but there was a significant reduction in the hepatic concentration of glutathione (-50%). The Tm of dibromosulphthalein was also significantly reduced (-36%) and its plasma and liver concentrations increased (+67% and +33%, respectively) in exercised rats. The results suggest that, in addition to the direct effect of liver glutathione depletion, other factors must be involved in the impairment of the biliary excretion of organic anions caused by exercise.