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The aim of this study was to determine the anaerobic threshold (AT) in a population of healthy and post-myocardial infarction men by applying Hinkley's mathematical method and comparing its performance to the ventilatory visual method. This mathematical model, in lieu of observer-dependent visual determination, can produce more reliable results due to the uniformity of the procedure. 17 middle-aged men (55±3 years) were studied in 2 groups: 9 healthy men (54±2 years); and 8 men with previous myocardial infarction (57±3 years). All subjects underwent an incremental ramp exercise test until physical exhaustion. Breath-by-breath ventilatory variables, heart rate (HR), and vastus lateralis surface electromyography (sEMG) signal were collected throughout the test. Carbon dioxide output (V˙CO2), HR, and sEMG were studied, and the AT determination methods were compared using correlation coefficients and Bland-Altman plots. Parametric statistical tests were applied with significance level set at 5%. No significant differences were found in the HR, sEMG, and ventilatory variables at AT between the different methods, such as the intensity of effort relative to AT. Moreover, important concordance and significant correlations were observed between the methods. We concluded that the mathematical model was suitable for detecting the AT in both healthy and myocardial infarction subjects.

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The purpose of this study was to investigate whether the critical force (CritF) and anaerobic impulse capacity (AIC) - estimated by tethered swimming - reflect the aerobic and anaerobic performance of swimmers. 12 swimmers performed incremental test in tethered swimming to determine lactate anaerobic threshold (AnTLAC), maximal oxygen uptake ( ˙VO2MAX) and force associated with the ˙VO2MAX (i ˙VO2MAX). The swimmers performed 4 exhaustive (tlim) exercise bouts (100, 110, 120 and 130% i ˙VO2MAX) to compute the CritF and AIC (F vs. 1/tlim model); a 30-s all-out tethered swimming bout to determine their anaerobic fitness (ANF); 100, 200, and 400-m time-trials to determine the swimming performance. CritF (57.09±11.77 N) did not differ from AnTLAC (53.96±11.52 N, (P>0.05) but was significantly lower than i ˙VO2MAX (71.02±8.36 N). In addition, CritF presented significant correlation with AnTLAC (r=0.76; P<0.05) and i ˙VO2MAX (r=0.74; P<0.05). On the other hand, AIC (286.19±54.91 N.s) and ANF (116.10±13.66 N) were significantly correlated (r=0.81, p<0.05). In addition, CritF and AIC presented significant correlations with all time-trials. In summary, this study demonstrates that CritF and AIC can be used to evaluate AnTLAC and ANF and to predict 100, 200, and 400-m free swimming.

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BACKGROUND: Allergic contact dermatitis is a frequent, often disabling disease caused by countless substances. Patch testing remains the gold standard test to identify the causative agent; however, it is subjective, time-consuming and not completely safe. Alternative methods were tried, but significant success has only been achieved with nickel. OBJECTIVE: Develop an alternative or complementary allergic contact dermatitis diagnostic test. METHODS: We compared the lymphocyte proliferative rate and cytokine production (IFN-γ, IL-2, IL-4, IL-5, IL-10, IL-12, IL-13, IL-17 and RANTES) between 18 chromium allergic patients and 19 controls. RESULTS: The lymphocyte proliferation test and some of the cytokines tested (IFN-γ, IL-2, IL-5, IL-12 and IL-13) were able to discriminate allergic patients. However, striking results were only achieved using IL-13, leading to an accuracy of about 90%. CONCLUSIONS: If further studies confirm the data found, IL-13 could be used as an alternative or complementary test to detect chromium contact allergy whereas lymphocyte proliferation test, IFN-γ, IL-2, IL-5 and IL-12 detections may serve as additional diagnostic tests.

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The objectives of this study were to evaluate and compare the use of linear and nonlinear methods for analysis of heart rate variability (HRV) in healthy subjects and in patients after acute myocardial infarction (AMI). Heart rate (HR) was recorded for 15 min in the supine position in 10 patients with AMI taking β-blockers (aged 57 ± 9 years) and in 11 healthy subjects (aged 53 ± 4 years). HRV was analyzed in the time domain (RMSSD and RMSM), the frequency domain using low- and high-frequency bands in normalized units (nu; LFnu and HFnu) and the LF/HF ratio and approximate entropy (ApEn) were determined. There was a correlation (P < 0.05) of RMSSD, RMSM, LFnu, HFnu, and the LF/HF ratio index with the ApEn of the AMI group on the 2nd (r = 0.87, 0.65, 0.72, 0.72, and 0.64) and 7th day (r = 0.88, 0.70, 0.69, 0.69, and 0.87) and of the healthy group (r = 0.63, 0.71, 0.63, 0.63, and 0.74), respectively. The median HRV indexes of the AMI group on the 2nd and 7th day differed from the healthy group (P < 0.05): RMSSD = 10.37, 19.95, 24.81; RMSM = 23.47, 31.96, 43.79; LFnu = 0.79, 0.79, 0.62; HFnu = 0.20, 0.20, 0.37; LF/HF ratio = 3.87, 3.94, 1.65; ApEn = 1.01, 1.24, 1.31, respectively. There was agreement between the methods, suggesting that these have the same power to evaluate autonomic modulation of HR in both AMI patients and healthy subjects. AMI contributed to a reduction in cardiac signal irregularity, higher sympathetic modulation and lower vagal modulation.

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The objectives of this study were to evaluate and compare the use of linear and nonlinear methods for analysis of heart rate variability (HRV) in healthy subjects and in patients after acute myocardial infarction (AMI). Heart rate (HR) was recorded for 15 min in the supine position in 10 patients with AMI taking ß-blockers (aged 57 ± 9 years) and in 11 healthy subjects (aged 53 ± 4 years). HRV was analyzed in the time domain (RMSSD and RMSM), the frequency domain using low- and high-frequency bands in normalized units (nu; LFnu and HFnu) and the LF/HF ratio and approximate entropy (ApEn) were determined. There was a correlation (P < 0.05) of RMSSD, RMSM, LFnu, HFnu, and the LF/HF ratio index with the ApEn of the AMI group on the 2nd (r = 0.87, 0.65, 0.72, 0.72, and 0.64) and 7th day (r = 0.88, 0.70, 0.69, 0.69, and 0.87) and of the healthy group (r = 0.63, 0.71, 0.63, 0.63, and 0.74), respectively. The median HRV indexes of the AMI group on the 2nd and 7th day differed from the healthy group (P < 0.05): RMSSD = 10.37, 19.95, 24.81; RMSM = 23.47, 31.96, 43.79; LFnu = 0.79, 0.79, 0.62; HFnu = 0.20, 0.20, 0.37; LF/HF ratio = 3.87, 3.94, 1.65; ApEn = 1.01, 1.24, 1.31, respectively. There was agreement between the methods, suggesting that these have the same power to evaluate autonomic modulation of HR in both AMI patients and healthy subjects. AMI contributed to a reduction in cardiac signal irregularity, higher sympathetic modulation and lower vagal modulation.

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We analyzed the usefulness of a semi-tethered field running test (STR) and the relationships between indices of anaerobic power, anaerobic capacity and running performance in 9 trained male sprinters (22.2 ± 2.9 yrs, 176 ± 1 cm, 68.0 ± 9.4 kg). STR involved an all out 120 m run attached to an apparatus that enabled power calculation from force and velocity measures. Subjects also carried out a cycloergometer Wingate Anaerobic Test (WT), an all out 300 m run and had accessed their maximal accumulated oxygen deficit (MAOD) on a treadmill. Peak and mean powers attained in STR (1720 ± 221 and 1391 ± 201 W) were greater but significantly related (r = 0.82; P < 0.01) to those in the WT (808 ± 130 and 603 ± 87 W). In addition, power measures derived from the STR were stronger related to running performance compared to those from the WT (r = 0.81-0.94 vs. 0.68-0.84; P < 0.05). Relationships between MAOD and most power indices were only weak to moderate. These results support the usefulness of STR for specific power assessment in field running and suggest that anaerobic power and capacity are not related entities, irrespective of having been evaluated using similar or dissimilar exercise modes.

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Estudou-se o efeito da aplicação de misoprostol intravaginal, na dilatação cervical de ovelhas Dorper, com o objetivo de se viabilizar a coleta transcervical de embriões. Para isso, 68 fêmeas foram sincronizadas com dispositivo intravaginal de progesterona, superovuladas com FSHp, inseminadas por laparoscopia com sêmen fresco, 36 horas após a remoção do dispositivo intravaginal, e submetidas à coleta transcervical de embriões. Os animais foram distribuídos em dois tratamentos: tratamento 1 (n=10), controle, sem aplicação de misoprostol intravaginal antes da coleta de embriões, e tratamento 2 (n=58), com aplicação prévia de 200µ g de misoprostol no fundo do saco vaginal, cinco horas antes da coleta dos embriões. Não foi possível realizar a transposição cervical em nenhum dos animais do tratamento 1, o que inviabilizou as coletas dos embriões, diferentemente do tratamento 2, em que foi possível a transposição cervical em 94,8 por cento dos animais (P<0,05). A técnica de coleta descrita foi realizada no tempo médio de 30,14±9,00 minutos, com recuperação média de 6,02±3,61 embriões/animal. Conclui-se que a técnica transcervical, com administração prévia vaginal de misoprostol, mostrou-se viável para coleta de embriões em ovelhas Dorper.(AU)

The effect of intravaginal misoprostol application on the cervical expansion in Dorper ewes was evaluated to make feasible the transcervical embryo recovery. Sixty-eight female donors were synchronized with an impregnated vaginal device of progesterone; superovulated with FSHp; inseminated by laparoscopy technique with fresh semen, 36 hours after the removal of impregnated vaginal device; and submitted to transcervical embryo recovery. The ewes were arranged in two treatments: treatment 1 (n=10), representing the control group, without intravaginal misoprostol application before embryo recovery; and treatment 2 (n=58), with application of 200µ g of misoprostol in the vagine, five hours before the embryo recovery. The control group did not allow the cervical transposition, making unfeasible the recovery. Animals from treatment 2 reached 94.8 percent of cervical transposition, resulting in significant (P<0.05) difference between treatments. The described recovery technique was accomplished in a mean time of 30.14±9.00 minutes, allowing a mean recovery of 6.02±3.61 of embryos per animal. It was concluded that the transcervical technique, with previous intravaginal misoprostol application, was a feasible method to recover embryos of Dorper ewes.(AU)

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Estudou-se o efeito da aplicação de misoprostol intravaginal, na dilatação cervical de ovelhas Dorper, com o objetivo de se viabilizar a coleta transcervical de embriões. Para isso, 68 fêmeas foram sincronizadas com dispositivo intravaginal de progesterona, superovuladas com FSHp, inseminadas por laparoscopia com sêmen fresco, 36 horas após a remoção do dispositivo intravaginal, e submetidas à coleta transcervical de embriões. Os animais foram distribuídos em dois tratamentos: tratamento 1 (n=10), controle, sem aplicação de misoprostol intravaginal antes da coleta de embriões, e tratamento 2 (n=58), com aplicação prévia de 200µ g de misoprostol no fundo do saco vaginal, cinco horas antes da coleta dos embriões. Não foi possível realizar a transposição cervical em nenhum dos animais do tratamento 1, o que inviabilizou as coletas dos embriões, diferentemente do tratamento 2, em que foi possível a transposição cervical em 94,8 por cento dos animais (P<0,05). A técnica de coleta descrita foi realizada no tempo médio de 30,14±9,00 minutos, com recuperação média de 6,02±3,61 embriões/animal. Conclui-se que a técnica transcervical, com administração prévia vaginal de misoprostol, mostrou-se viável para coleta de embriões em ovelhas Dorper.

The effect of intravaginal misoprostol application on the cervical expansion in Dorper ewes was evaluated to make feasible the transcervical embryo recovery. Sixty-eight female donors were synchronized with an impregnated vaginal device of progesterone; superovulated with FSHp; inseminated by laparoscopy technique with fresh semen, 36 hours after the removal of impregnated vaginal device; and submitted to transcervical embryo recovery. The ewes were arranged in two treatments: treatment 1 (n=10), representing the control group, without intravaginal misoprostol application before embryo recovery; and treatment 2 (n=58), with application of 200µ g of misoprostol in the vagine, five hours before the embryo recovery. The control group did not allow the cervical transposition, making unfeasible the recovery. Animals from treatment 2 reached 94.8 percent of cervical transposition, resulting in significant (P<0.05) difference between treatments. The described recovery technique was accomplished in a mean time of 30.14±9.00 minutes, allowing a mean recovery of 6.02±3.61 of embryos per animal. It was concluded that the transcervical technique, with previous intravaginal misoprostol application, was a feasible method to recover embryos of Dorper ewes.

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BACKGROUND: Lymphocyte proliferation testing (LPT) has some advantages over patch testing to diagnose allergic contact dermatitis. It is harmless, objective and can be used in clinical situations where patch testing is not recommended. Unfortunately, significant success has only been achieved with nickel. There are few studies on chromium LPT and they were performed with different methods, leading to inconsistent results. METHODS: To determine the best parameters for chromium LPT, we tested 20 patients with allergic contact dermatitis to the metal and 20 controls, using various protocols. RESULTS: The best sensitivity and specificity ratios were achieved with 6-day cultures stimulated with a range from 7.5 x 10(-4) to 5 x 10(-3) mol/L of nonfiltered chromium chloride solutions. The sensitivity, specificity and accuracy values found within this range were 65%, 95% and 80%, respectively. CONCLUSION: Further investigation is necessary to achieve better sensitivity values.

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