66 resultados para Log ESEO, GPS, orbite, pseudorange, least square
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BACKGROUND: Mental disorders, common in primary care, are often associated with physical complaints. While exposure to psychosocial stressors and development or presence of principal mental disorders (i.e. depression, anxiety and somatoform disorders defined as multisomatoforme disorders) is commonly correlated, temporal association remains unproven. The study explores the onset of such disorders after exposure to psychosocial stressors in a cohort of primary care patients with at least one physical symptom. METHOD: The cohort study SODA (SOmatization, Depression and Anxiety) was conducted by 21 private-practice GPs and three fellow physicians in a Swiss academic primary care centre. GPs included patients via randomized daily identifiers. Depression, anxiety or somatoform disorders were identified by the full Patient Health Questionnaire (PHQ), a validated procedure to identify mental disorders based on DSM-IV criteria. The PHQ was also used to investigate exposure to psychosocial stressors (before the index consultation and during follow up) and the onset of principal mental disorders after one year of follow up. RESULTS: From November 2004 to July 2005, 1020 patients were screened for inclusion. 627 were eligible and 482 completed the PHQ one year later and were included in the analysis (77%). At one year, prevalence of principal mental disorders was 30/153 (19.6% CI95% 13.6; 26.8) for those initially exposed to a major psychosocial stressor and 26/329 (7.9% CI95% 5.2; 11.4) for those not. Stronger association exists between psychosocial stressors and depression (RR = 2.4) or anxiety (RR = 3.5) than multisomatoforme disorders (RR = 1.8). Patients who are "bothered a lot" (subjective distress) by a stressor are therefore 2.5 times (CI95% 1.5; 4.0) more likely to experience a mental disorder at one year. A history of psychiatric comorbidities or psychological treatment was not a confounding factor for developing a principal mental disorder after exposure to psychosocial stressors. CONCLUSION: This primary care study shows that patients with physical complaints exposed to psychosocial stressors had a higher risk for developing mental disorders one year later. This temporal association opens the field for further research in preventive care for mental diseases in primary care patients.
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Goal: To validate oral vatgancictovir (VGC) in the prophylaxis of CMV infection in Lung (Lu) and Liver (L) recipients and in the treatment of CMV infection/disease in solid organ transplant recipients, using pharmacokinetic and pharmacodynamic studies in comparison with i/v gancicLovir (GCV). Methods: patients undergoing organ transpLantation donor or recipient CMV-seropositive receiving VGC prophylaxis for a period of 3 months (D+/R- Lung recipients, 6 months) were enroLLed. Heart (H), Lu, and L recipients received 900mg VGC q.d., adjusted to kidney (K) function. No K recipients received more than 450mg of VGC q.d. GCV trough (Ctrough) and peak (Cpeak = 3 hours after drug administration) LeveLs, and CMV DNA were measured at 7, 30, and 60 days post-transpLant (prophyLactic study). Patients who developed CMV infection/disease after stopping prophylaxis were treated with VGC (1800mg per day adjusted to K function and GCV blood LeveLs). GCV trough and peak LeveLs, and CMV DNA were measured weekly for the first 3 weeks and biweekly thereafter, until therapy cessation (therapeutic study). PLasma concentration of GCV is measured by HPLC. Results: In the first 8 prophyLaxed patients (6 K, and 1 L and 1 H transplant recipient) of 450mg VGC q.d., the average GCV concentration was 0.5±0.3 mg/t at trough, and 3.9±l.0mg/t 3 hours after administration. Inter-patient variability was substantiaL, especiaLLy for Ctrough (63% of total variance), which correlated with the patient's estimated gtomerutar filtration rate (r square = 42%). No CMV DNA was detected during VGC prophy- Laxis. Two patients (1 H and 1 L) were treated for Late CMV disease. Average GCV Cpeak were 8.9±2.3 mg/L and 4.6±0.5 rag/L, and GCV Ctrough were 2.0±0.9 mg/t and 1.6±0.2 mg/t respectively in each patient during induction phase. VGC treatment afforded a decrease in CMV DNA from 5.2 and 4.4 Log copies/10E6 cettutes at week 0, to 3.9 and 3.0 at week 1, and 3.3 and 2.1 at week 3, respectively.
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Object The goal of this study was to establish whether clear patterns of initial pain freedom could be identified when treating patients with classic trigeminal neuralgia (TN) by using Gamma Knife surgery (GKS). The authors compared hypesthesia and pain recurrence rates to see if statistically significant differences could be found. Methods Between July 1992 and November 2010, 737 patients presenting with TN underwent GKS and prospective evaluation at Timone University Hospital in Marseille, France. In this study the authors analyzed the cases of 497 of these patients, who participated in follow-up longer than 1 year, did not have megadolichobasilar artery- or multiple sclerosis-related TN, and underwent GKS only once; in other words, the focus was on cases of classic TN with a single radiosurgical treatment. Radiosurgery was performed with a Leksell Gamma Knife (model B, C, or Perfexion) using both MR and CT imaging targeting. A single 4-mm isocenter was positioned in the cisternal portion of the trigeminal nerve at a median distance of 7.8 mm (range 4.5-14 mm) anterior to the emergence of the nerve. A median maximum dose of 85 Gy (range 70-90 Gy) was delivered. Using empirical methods and assisted by a chart with clear cut-off periods of pain free distribution, the authors were able to divide patients who experienced freedom from pain into 3 separate groups: patients who became pain free within the first 48 hours post-GKS; those who became pain free between 48 hours and 30 days post-GKS; and those who became pain free more than 30 days after GKS. Results The median age in the 497 patients was 68.3 years (range 28.1-93.2 years). The median follow-up period was 43.75 months (range 12-174.41 months). Four hundred fifty-four patients (91.34%) were initially pain free within a median time of 10 days (range 1-459 days) after GKS. One hundred sixty-nine patients (37.2%) became pain free within the first 48 hours (Group PF(≤ 48 hours)), 194 patients (42.8%) between posttreatment Day 3 and Day 30 (Group PF((>48 hours, ≤ 30 days))), and 91 patients (20%) after 30 days post-GKS (Group PF(>30 days)). Differences in postoperative hypesthesia were found: in Group PF(≤ 48 hours) 18 patients (13.7%) developed postoperative hypesthesia, compared with 30 patients (19%) in Group PF((>48 hours, ≤ 30 days)) and 22 patients (30.6%) in Group PF(>30 days) (p = 0.014). One hundred fifty-seven patients (34.4%) who initially became free from pain experienced a recurrence of pain with a median delay of 24 months (range 0.62-150.06 months). There were no statistically significant differences between the patient groups with respect to pain recurrence: 66 patients (39%) in Group PF(≤ 48 hours) experienced pain recurrence, compared with 71 patients (36.6%) in Group PF((>48 hours, ≤ 30 days)) and 27 patients (29.7%) in Group PF(>30 days) (p = 0.515). Conclusions A substantial number of patients (169 cases, 37.2%) became pain free within the first 48 hours. The rate of hypesthesia was higher in patients who became pain free more than 30 days after GKS, with a statistically significant difference between patient groups (p = 0.014).
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BACKGROUND: We have developed a nonviral gene therapy method based on the electrotransfer of plasmid in the ciliary muscle. These easily accessible smooth muscle cells could be turned into a biofactory for any therapeutic proteins to be secreted in a sustained manner in the ocular media. METHODS: Electrical conditions, design of electrodes, plasmid formulation, method and number of injections were optimized in vivo in the rat by localizing β-galactosidase expression and quantifying reporter (luciferase) and therapeutic (anti-tumor necrosis factor) proteins secretion in the ocular media. Anatomical measurements were performed via human magnetic resonance imaging to design a human eye-sized prototype that was tested in the rabbit. RESULTS: In the rat, transscleral injection of 30 µg of plasmid diluted in half saline (77 mM NaCl) followed by application of eight square-wave electrical pulses (15 V, 10 ms, 5.3 Hz) using two platinum/iridium electrodes, an internal wire and an external sheet, delivered plasmid efficiently to the ciliary muscle fibers. Gene transfer resulted in a long-lasting (at least 5 months) and plasmid dose-/injection number- dependent secretion of different molecular weight proteins mainly in the vitreous, without any systemic exposure. Because ciliary muscle anatomical measurements remained constant among ages in adult humans, an integrated device comprising needle-electrodes was designed and manufactured. Its usefulness was validated in the rabbit. CONCLUSIONS: Plasmid electrotransfer to the ciliary muscle with a suitable medical device represents a promising local and sustained protein delivery system for treating posterior segment diseases, avoiding repeated intraocular injections.
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The purpose of the present article is to take stock of a recent exchange in Organizational Research Methods between critics (Rönkkö & Evermann, 2013) and proponents (Henseler et al., 2014) of partial least squares path modeling (PLS-PM). The two target articles were centered around six principal issues, namely whether PLS-PM: (1) can be truly characterized as a technique for structural equation modeling (SEM); (2) is able to correct for measurement error; (3) can be used to validate measurement models; (4) accommodates small sample sizes; (5) is able to provide null hypothesis tests for path coefficients; and (6) can be employed in an exploratory, model-building fashion. We summarize and elaborate further on the key arguments underlying the exchange, drawing from the broader methodological and statistical literature in order to offer additional thoughts concerning the utility of PLS-PM and ways in which the technique might be improved. We conclude with recommendations as to whether and how PLS-PM serves as a viable contender to SEM approaches for estimating and evaluating theoretical models.
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Introduction: The Thalidomide-Dexamethasone (TD) regimen has provided encouraging results in relapsed MM. To improve results, bortezomib (Velcade) has been added to the combination in previous phase II studies, the so called VTD regimen. In January 2006, the European Group for Blood and Marrow Transplantation (EBMT) and the Intergroupe Francophone du Myélome (IFM) initiated a prospective, randomized, parallel-group, open-label phase III, multicenter study, comparing VTD (arm A) with TD (arm B) for MM patients progressing or relapsing after autologous transplantation. Patients and Methods: Inclusion criteria: patients in first progression or relapse after at least one autologous transplantation, including those who had received bortezomib or thalidomide before transplant. Exclusion criteria: subjects with neuropathy above grade 1 or non secretory MM. Primary study end point was time to progression (TTP). Secondary end points included safety, response rate, progression-free survival (PFS) and overall survival (OS). Treatment was scheduled as follows: bortezomib 1.3 mg/m2 was given as an i.v bolus on Days 1, 4, 8 and 11 followed by a 10-Day rest period (days 12 to 21) for 8 cycles (6 months) and then on Days 1, 8, 15, 22 followed by a 20-Day rest period (days 23 to 42) for 4 cycles (6 months). In both arms, thalidomide was scheduled at 200 mg/Day orally for one year and dexamethasone 40 mg/Day orally four days every three weeks for one year. Patients reaching remission could proceed to a new stem cell harvest. However, transplantation, either autologous or allogeneic, could only be performed in patients who completed the planned one year treatment period. Response was assessed by EBMT criteria, with additional category of near complete remission (nCR). Adverse events were graded by the NCI-CTCAE, Version 3.0.The trial was based on a group sequential design, with 4 planned interim analyses and one final analysis that allowed stopping for efficacy as well as futility. The overall alpha and power were set equal to 0.025 and 0.90 respectively. The test for decision making was based on the comparison in terms of the ratio of the cause-specific hazards of relapse/progression, estimated in a Cox model stratified on the number of previous autologous transplantations. Relapse/progression cumulative incidence was estimated using the proper nonparametric estimator, the comparison was done by the Gray test. PFS and OS probabilities were estimated by the Kaplan-Meier curves, the comparison was performed by the Log-Rank test. An interim safety analysis was performed when the first hundred patients had been included. The safety committee recommended to continue the trial. Results: As of 1st July 2010, 269 patients had been enrolled in the study, 139 in France (IFM 2005-04 study), 21 in Italy, 38 in Germany, 19 in Switzerland (a SAKK study), 23 in Belgium, 8 in Austria, 8 in the Czech republic, 11 in Hungary, 1 in the UK and 1 in Israel. One hundred and sixty nine patients were males and 100 females; the median age was 61 yrs (range 29-76). One hundred and thirty six patients were randomized to receive VTD and 133 to receive TD. The current analysis is based on 246 patients (124 in arm A, 122 in arm B) included in the second interim analysis, carried out when 134 events were observed. Following this analysis, the trial was stopped because of significant superiority of VTD over TD. The remaining patients were too premature to contribute to the analysis. The number of previous autologous transplants was one in 63 vs 60 and two or more in 61 vs 62 patients in arm A vs B respectively. The median follow-up was 25 months. The median TTP was 20 months vs 15 months respectively in arm A and B, with cumulative incidence of relapse/progression at 2 years equal to 52% (95% CI: 42%-64%) vs 70% (95% CI: 61%-81%) (p=0.0004, Gray test). The same superiority of arm A was also observed when stratifying on the number of previous autologous transplantations. At 2 years, PFS was 39% (95% CI: 30%-51%) vs 23% (95% CI: 16%-34%) (A vs B, p=0.0006, Log-Rank test). OS in the first two years was comparable in the two groups. Conclusion: VTD resulted in significantly longer TTP and PFS in patients relapsing after ASCT. Analysis of response and safety data are on going and results will be presented at the meeting.
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PURPOSE: This descriptive article illustrates the application of Global Positioning System (GPS) professional receivers in the field of locomotion studies. The technological challenge was to assess the external mechanical work in outdoor walking. METHODS: Five subjects walked five times during 5 min on an athletic track at different imposed stride frequency (from 70-130 steps x min(-1)). A differential GPS system (carrier phase analysis) measured the variation of the position of the trunk at 5 Hz. A portable indirect calorimeter recorded breath-by-breath energy expenditure. RESULTS: For a walking speed of 1.05 +/- 0.11 m x s(-1), the vertical lift of the trunk (43 +/- 14 mm) induced a power of 46.0 +/- 20.4 W. The average speed variation per step (0.15 +/- 0.03 m x s(-1)) produced a kinetic power of 16.9 +/- 7.2 W. As compared with commonly admitted values, the energy exchange (recovery) between the two energy components was low (39.1 +/- 10.0%), which induced an overestimated mechanical power (38.9 +/- 18.3 W or 0.60 W x kg(-1) body mass) and a high net mechanical efficiency (26.9 +/- 5.8%). CONCLUSION: We assumed that the cause of the overestimation was an unwanted oscillation of the GPS antenna. It is concluded that GPS (in phase mode) is now able to record small body movements during human locomotion, and constitutes a promising tool for gait analysis of outdoor unrestrained walking. However, the design of the receiver and the antenna must be adapted to human experiments and a thorough validation study remains to be conducted.
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Infection with hepatitis C virus (HCV) is associated with lymphoproliferative disorders, represented by essential mixed cryoglobulinemia and B-cell non-Hodgkin's lymphoma, but the pathogenic mechanism remains obscure. HCV may infect B cells or interact with their cell surface receptors, and induce lymphoproliferation. The influence of HCV infection of B cells on the development of lymphoproliferative disorders was evaluated in 75 patients with persistent HCV infection. HCV infection was more prevalent (63% vs. 16%, 14%, or 17% P < 0.05 for each), and HCV RNA levels were higher (3.35 +/- 3.85 vs. 1.75 +/- 2.52, 2.15 +/- 2.94 or 2.10 +/- 2.90 log copies/100 ng, P < 0.01 for each) in B cells than CD4(+), CD8(+) T cells or other cells. Negative-strand HCV RNA, as a marker of viral replication, was detected in B cells from four of the 75 (5%) patients. Markers for lymphoproliferative disorders were more frequent in the 50 patients with chronic hepatitis C than the 32 with chronic hepatitis B, including cryoglobulinemia (26% vs. 0%, P < 0.001), low CH(50) levels (48% vs. 3%, P = 0.012), and the clonality of B cells (12% vs. 0%, P < 0.01). By multivariate analysis, HCV RNA in B cells was an independent factor associated with the presence of at least one marker for lymphoproliferation (odds ratio: 1.98 [95% confidence interval: 1.36-7.24], P = 0.027). Based on the results obtained, the infection of B cells with HCV would play an important role in the development of lymphoproliferative disorders.
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Purpose: To examine the efficacy and safety of repeat deep sclerectomy (DS) versus Baerveldt shunt (BS) implantation as second line surgery following failed primary DS. Methods: Fifty one patients were prospectively recruited to undergo BS implantation following failed DS and 51 patients underwent repeat DS, for which data was collected retrospectively. All eyes had at least one failed DS. Surgical success was defined as IOP≤21mmHg and 20% reduction in IOP from baseline. Success rates, number of glaucoma medications (GMs), IOP, and complication rates were compared between the two groups at year 1, post-operatively. Results: Mean age, sex and the proportion of glaucoma subtypes were similar between groups. Preoperatively IOP was significantly lower in DS group vs BS group (18.8mmHg vs 23.8mmHg, p<0.01, two sample t-test). Postoperatively IOP was significantly higher in DS group than BS group (14.6mmHg vs 12.0mmHg, p<0.01, two-sample t-test). In the DS group, 47% of eyes did not achieve 20% reduction in IOP from baseline, as a result the success rates were significantly lower in eyes with DS (51%) than in eyes with BS (88%) (p=0.02, log-rank test). Preoperatively the number of GMs used in DS and BS groups were similar (2.2 vs 2.7 p=0.02, two sample t-test). Postoperatively there remained no significant difference in GMs between groups (0.9 vs 1.1, p= 0.58, two sample t-test). Complication rates were similar between the two groups (12% vs 10%). Conclusions: Baerveldt tube implantation was more effective in lowering IOP than repeat deep sclerectomy in eyes with failed primary DS, at year one. Complications were minor and infrequent in both groups
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BACKGROUND: New methods of ultra-rapid opiate detoxification (URD) under intravenous sedation have been criticized because of limited data on safety and long-term follow-up. Premedication with buprenorphine has been advocated to improve safety by decreasing vomiting. Prior research has not explored URD in socially impaired patients. METHOD: Sixteen patients were detoxified with URD and prospectively evaluated over at least 30 months. Data of this procedure were compared with those of our previous study without buprenorphine preparation (Drug Alcohol Depend. 52(3) (1998) 243). The 16 patients were followed up by a general practitioner (GP) before and after URD. The GPs also supervised the 7-day course of buprenorphine treatment prescribed for the 16 patients prior to URD. RESULTS: During the procedure, only one episode of vomiting occurred instead of 13 out of 20 in our previous study. Post-procedure, only two patients experienced moderate withdrawal symptoms, such as persistent nausea, abdominal cramps and vomiting lasting from 24 to 48 h, in comparison with most patients in the previous study without buprenorphine. After a period of at least 30 months (36.0+/-6.38), the 16 patients were still alive and were regularly monitored by their GP. Only two of the 16 never relapsed after URD and reported total opiate abstinence. Fourteen patients relapsed; 12 of these were prescribed a licensed methadone substitution program and two were still using heroin. CONCLUSION: In this small sample, the data indicated that URD with buprenorphine preparation was safe and that it markedly decreased post-procedure morbidity. No patient died over a minimum 30-month follow-up period. Furthermore, the procedure was employed with socially impaired patients. In the long term, a few patients were still free of opiates, while the majority opted for a methadone maintenance program, showing that URD can serve as one possible step in a long-term treatment program.
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BACKGROUND AND PURPOSE: Knowledge of cerebral blood flow (CBF) alterations in cases of acute stroke could be valuable in the early management of these cases. Among imaging techniques affording evaluation of cerebral perfusion, perfusion CT studies involve sequential acquisition of cerebral CT sections obtained in an axial mode during the IV administration of iodinated contrast material. They are thus very easy to perform in emergency settings. Perfusion CT values of CBF have proved to be accurate in animals, and perfusion CT affords plausible values in humans. The purpose of this study was to validate perfusion CT studies of CBF by comparison with the results provided by stable xenon CT, which have been reported to be accurate, and to evaluate acquisition and processing modalities of CT data, notably the possible deconvolution methods and the selection of the reference artery. METHODS: Twelve stable xenon CT and perfusion CT cerebral examinations were performed within an interval of a few minutes in patients with various cerebrovascular diseases. CBF maps were obtained from perfusion CT data by deconvolution using singular value decomposition and least mean square methods. The CBF were compared with the stable xenon CT results in multiple regions of interest through linear regression analysis and bilateral t tests for matched variables. RESULTS: Linear regression analysis showed good correlation between perfusion CT and stable xenon CT CBF values (singular value decomposition method: R(2) = 0.79, slope = 0.87; least mean square method: R(2) = 0.67, slope = 0.83). Bilateral t tests for matched variables did not identify a significant difference between the two imaging methods (P >.1). Both deconvolution methods were equivalent (P >.1). The choice of the reference artery is a major concern and has a strong influence on the final perfusion CT CBF map. CONCLUSION: Perfusion CT studies of CBF achieved with adequate acquisition parameters and processing lead to accurate and reliable results.
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BACKGROUND: While rifaximin was able to improve symptoms in patients with irritable bowel syndrome (IBS) in phase III trials, these results are yet to be repeated in phase IV studies. AIM: To evaluate the treatment response to rifaximin in IBS patients in a phase IV trial. METHODS: IBS patients underwent lactulose hydrogen breath testing (LHBT). LHBT-positive patients were treated with rifaximin for 14 days. Prior to treatment as well as at week 4 and 14 following the start of rifaximin treatment, patients completed a questionnaire assessing symptom severity on a Likert scale from 0 to 10. RESULTS: One hundred and six of 150 IBS patients (71%) were LHBT-positive and treated with rifaximin. As assessed at week 4 following commencement of the therapy, rifaximin provided significant improvement of the following IBS-associated symptoms: bloating (5.5±2.6 before the start of the treatment vs. 3.6±2.7 at week 4, P<0.001), flatulence (5.0±2.7 vs. 4.0±2.7, P=0.015), diarrhoea (2.9±2.4 vs. 2.0±2.4, P=0.005) and abdominal pain (4.8±2.7 vs. 3.3±2.5, P<0.001). Overall well-being also significantly improved (3.9 ± 2.4 vs. 2.7 ± 2.3, P < 0.001). Similar improvements in IBS symptoms were obtained at week 14. Eighty-six per cent of patients undergoing repetitive LHBT (55/64) tested negative at week 4. CONCLUSIONS: We found a high percentage of LHBT-positive IBS patients. IBS-associated symptoms (bloating, flatulence, diarrhoea, pain) were improved for a period of 3 months following 2 weeks of treatment with rifaximin. We conclude that rifaximin treatment alleviates symptoms in LHBT-positive IBS patients.
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We propose robust estimators of the generalized log-gamma distribution and, more generally, of location-shape-scale families of distributions. A (weighted) Q tau estimator minimizes a tau scale of the differences between empirical and theoretical quantiles. It is n(1/2) consistent; unfortunately, it is not asymptotically normal and, therefore, inconvenient for inference. However, it is a convenient starting point for a one-step weighted likelihood estimator, where the weights are based on a disparity measure between the model density and a kernel density estimate. The one-step weighted likelihood estimator is asymptotically normal and fully efficient under the model. It is also highly robust under outlier contamination. Supplementary materials are available online.
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We assessed neuromuscular fatigue and recovery of the plantar flexors after playing football with or without severe heat stress. Neuromuscular characteristics of the plantar flexors were assessed in 17 male players at baseline and ∼30 min, 24, and 48 h after two 90-min football matches in temperate (∼20 °C and 55% rH) and hot (∼43 °C and 20% rH) environments. Measurements included maximal voluntary strength, muscle activation, twitch contractile properties, and rate of torque development and soleus EMG (i.e., root mean square activity) rise from 0 to 30, -50, -100, and -200 ms during maximal isometric contractions for plantar flexors. Voluntary activation and peak twitch torque were equally reduced (-1.5% and -16.5%, respectively; P < 0.05) post-matches relative to baseline in both conditions, the latter persisting for at least 48 h, whereas strength losses (∼5%) were not significant. Absolute explosive force production declined (P < 0.05) 30 ms after contraction onset independently of condition, with no change at any other epochs. Globally, normalized rate of force development and soleus EMG activity rise values remained unchanged. In football, match-induced alterations in maximal and rapid torque production capacities of the plantar flexors are moderate and do not differ after competing in temperate and hot environments.