124 research outputs found
Effects of caffeine supplementation on physical performance and mood dimensions in elite and trained-recreational athletes.
Background: Caffeine supplementation (CAFF) has an established ergogenic effect on physical performance and
the psychological response to exercise. However, few studies have compared the response to CAFF intake among
athletes of different competition level. This study compares the acute effects of CAFF on anaerobic performance,
mood and perceived effort in elite and moderately-trained recreational athletes.
Methods: Participants for this randomized, controlled, crossover study were 8 elite athletes (in the senior boxing
national team) and 10 trained-recreational athletes. Under two experimental conditions, CAFF supplementation
(6 mg/kg) or placebo (PLAC), the athletes completed a Wingate test. Subjective exertion during the test was
recorded as the rating of perceived exertion (RPE) both at the general level (RPEgeneral) and at the levels
muscular (RPEmuscular) and cardiorespiratory (RPEcardio). Before the Wingate test, participants completed the
questionnaires Profiles of Moods States (POMS) and Subjective Vitality Scale (SVS).
Results: In response to CAFF intake, improvements were noted in Wpeak (11.22 ± 0.65 vs 10.70 ± 0.84; p =
0.003; η2
p =0.44), Wavg (8.75 ± 0.55 vs 8.41 0.46; p = 0.001; η2
p =0.53) and time taken to reach Wpeak (7.56 ± 1.58
vs 9.11 ± 1.53; p < 0.001; η2
p =0.57) both in the elite and trained-recreational athletes. However, only the elite
athletes showed significant increases in tension (+ 325%), vigor (+ 31%) and SVS (+ 28%) scores after the
intake of CAFF compared to levels recorded under the condition PLAC (p < 0.05). Similarly, levels of vigor
after consuming CAFF were significantly higher in the elite than the trained-recreational athletes (+ 5.8%).
Conclusions: CAFF supplementation improved anaerobic performance in both the elite and recreational
athletes. However, the ergogenic effect of CAFF on several mood dimensions and subjective vitality was
greater in the elite athletes.post-print700 K
Caffeine supplementation improves physical performance without affecting fatigue level: a double-blind crossover study.
This study examined the effect of caffeine supplementation (CAFF) in a Wingate test (WT), and
the behaviour of blood lactate concentrations (BLa) and neuromuscular fatigue (NMF), measured as reduced
countermovement jump (CMJ) performance, in response to the WT. In a double-blind crossover study, 16 participants
attended the laboratory twice, separated by a 72-hour window. In the sessions, participants first ingested
6 mg·kg-1 of either CAFF or placebo (PLAC), and then performed a WT. BLa was measured before (L-pre), and
0.5 min (L-post-0.5) and 3.5 min (L-post-3.5) after conducting the WT. The CMJ test was conducted before (CMJ
pre), after (CMJ post), and 3 min after completing (CMJ post-3) the WT. The results indicated that CAFF enhanced
peak power (Wpeak: + 3.22%; p = 0.040), time taken to reach Wpeak (T_Wpeak: -18.76%; p = 0.001) and
mean power (Wmean: + 2.7%; p = 0.020). A higher BLa was recorded for CAFF at L-post-0.5 (+ 13.29%;
p = 0.009) and L-post-3.5 (+ 10.51%; p = 0.044) compared to PLAC. CAFF improved peak power (PP; + 3.44%;
p = 0.003) and mean power (MP; + 4.78%; p = 0.006) at CMJ pre, compared to PLAC, whereas PP and MP
were significantly diminished at CMJ post and CMJ post-3 compared to pre (p < 0.001 for all comparisons)
under both the CAFF and PLAC conditions. PP and MP were increased at post-3 compared to post (p < 0.001
for all comparisons) for both conditions. In conclusion, CAFF increased WT performance and BLa without affecting
NMF measured by CMJ. Thus, CAFF may allow athletes to train with higher workloads and enhance the
supercompensation effects after an adequate recovery period.post-print756 K
Impact of uterine manipulator on oncological outcome in endometrial cancer surgery
Background: There are limited data available to indicate whether oncological outcomes might be influenced by the uterine manipulator, which is used at the time of hysterectomy for minimally invasive surgery in patients with endometrial cancer. The current evidence derives from retrospective studies with limited sample sizes. Without substantial evidence to support its use, surgeons are required to make decisions about its use based only on their personal choice and surgical experience.
Objective: To evaluate the use of the uterine manipulator on oncological outcomes after minimally invasive surgery, for apparent early-stage endometrial cancer. Study Design: We performed a retrospective multicentric study to assess the oncological safety of uterine manipulator use in patients with apparent early-stage endometrial cancer, treated with minimally invasive surgery. The type of manipulator, surgical staging, histology, lymphovascular space invasion, International Federation of Gynecology and Obstetrics stage, adjuvant treatment, recurrence, and pattern of recurrence were evaluated. The primary objective was to determine the relapse rate. The secondary objective was to determine recurrence-free survival, overall survival, and the pattern of recurrence.
Results: A total of 2661 women from 15 centers were included; 1756 patients underwent hysterectomy with a uterine manipulator and 905 without it. Both groups were balanced with respect to histology, tumor grade, myometrial invasion, International Federation of Gynecology and Obstetrics stage, and adjuvant therapy. The rate of recurrence was 11.69% in the uterine manipulator group and 7.4% in the no-manipulator group (P<.001). The use of the uterine manipulator was associated with a higher risk of recurrence (hazard ratio, 2.31; 95% confidence interval, 1.27â4.20; P=.006). The use of uterine manipulator in uterus-confined endometrial cancer (International Federation of Gynecology and Obstetrics [FIGO] IâII) was associated with lower disease-free survival (hazard ratio, 1.74; 95% confidence interval, 0.57â0.97; P=.027) and higher risk of death (hazard ratio, 1.74; 95% confidence interval, 1.07â2.83; P=.026). No differences were found regarding the pattern of recurrence between both groups (chi-square statistic, 1.74; P=.63).
Conclusion: In this study, the use of a uterine manipulator was associated with a worse oncological outcome in patients with uterus-confined endometrial cancer (International Federation of Gynecology and Obstetrics IâII) who underwent minimally invasive surgery. Prospective trials are essential to confirm these results
Wage inequality, segregation by skill and the price of capital in an assignment model
Some pieces of empirical evidence suggest that in the U.S., over the last few decades, (i) wage inequality between-plants has risen much more than wage inequality within-plants and (ii) there has been an increase in the segregation of workers by skill into separate plants. This paper presents a frictionless assignment model in which these two features can be explained simultaneously as the result of the decline in the relative price of capital. Additional implications of the model regarding the skill premium and the dispersion in labor productivity across plants are also consistent with the empirical evidence. [resumen de autor
Perioperative management and anaesthetic considerations in pelvic exenterations using Delphi methodology: Results from the PelvEx Collaborative
Background: The multidisciplinary perioperative and anaesthetic management of patients undergoing pelvic exenteration is essential for good surgical outcomes. No clear guidelines have been established, and there is wide variation in clinical practice internationally. This consensus statement consolidates clinical experience and best practice collectively, and systematically addresses key domains in the perioperative and anaesthetic management. Methods: The modified Delphi methodology was used to achieve consensus from the PelvEx Collaborative. The process included one round of online questionnaire involving controlled feedback and structured participant response, two rounds of editing, and one round of web-based voting. It was held from December 2019 to February 2020. Consensus was defined as more than 80 per cent agreement, whereas less than 80 per cent agreement indicated low consensus. Results: The final consensus document contained 47 voted statements, across six key domains of perioperative and anaesthetic management in pelvic exenteration, comprising preoperative assessment and preparation, anaesthetic considerations, perioperative management, anticipating possible massive haemorrhage, stress response and postoperative critical care, and pain management. Consensus recommendations were developed, based on consensus agreement achieved on 34 statements. Conclusion: The perioperative and anaesthetic management of patients undergoing pelvic exenteration is best accomplished by a dedicated multidisciplinary team with relevant domain expertise in the setting of a specialized tertiary unit. This consensus statement has addressed key domains within the framework of current perioperative and anaesthetic management among patients undergoing pelvic exenteration, with an international perspective, to guide clinical practice, and has outlined areas for future clinical research
Contemporary Management of Locally Advanced and Recurrent Rectal Cancer: Views from the PelvEx Collaborative
Pelvic exenteration is a complex operation performed for locally advanced and recurrent pelvic cancers. The goal of surgery is to achieve clear margins, therefore identifying adjacent or involved organs, bone, muscle, nerves and/or vascular structures that may need resection. While these extensive resections are potentially curative, they can be associated with substantial morbidity. Recently, there has been a move to centralize care to specialized units, as this facilitates better multi-disciplinary care input. Advancements in pelvic oncology and surgical innovation have redefined the boundaries of pelvic exenterative surgery. Combined with improved neoadjuvant therapies, advances in diagnostics, and better reconstructive techniques have provided quicker recovery and better quality of life outcomes, with improved survival This article provides highlights of the current management of advanced pelvic cancers in terms of surgical strategy and potential future developments
Induction chemotherapy followed by chemoradiotherapy versus chemoradiotherapy alone as neoadjuvant treatment for locally recurrent rectal cancer: Study protocol of a multicentre, open-label, parallel-arms, randomized controlled study (PelvEx II)
Background: A resection with clear margins (R0 resection) is the most important prognostic factor in patients with locally recurrent rectal cancer (LRRC). However, this is achieved in only 60 per cent of patients. The aim of this study is to investigate whether the addition of induction chemotherapy to neoadjuvant chemo(re)irradiation improves the R0 resection rate in LRRC. Methods: Thismulticentre, international, open-label, phase III, parallel-arms study will enrol 364 patients with resectable LRRC after previous partial or total mesorectal resection without synchronous distant metastases or recent chemo- and/or radiotherapy treatment. Patients will be randomized to receive either induction chemotherapy (three 3-week cycles of CAPOX (capecitabine, oxaliplatin), four 2- week cycles of FOLFOX (5-fluorouracil, leucovorin, oxaliplatin) or FOLFORI (5-fluorouracil, leucovorin, irinotecan)) followed by neoadjuvant chemoradiotherapy and surgery (experimental arm) or neoadjuvant chemoradiotherapy and surgery alone (control arm). Tumours will be restaged usingMRI and, in the experimental arm, a further cycle of CAPOX or two cycles of FOLFOX/FOLFIRI will be administered before chemoradiotherapy in case of stable or responsive disease. The radiotherapy dose will be 25 Ă 2.0 Gy or 28 Ă 1.8Gy in radiotherapy-naive patients, and 15 Ă 2.0Gy in previously irradiated patients. The concomitant chemotherapy agent will be capecitabine administered twice daily at a dose of 825mg/m2 on radiotherapy days. The primary endpoint of the study is the R0 resection rate. Secondary endpoints are long-termoncological outcomes, radiological and pathological response, toxicity, postoperative complications, costs, and quality of life. Discussion: This trial protocol describes the PelvEx II study. PelvEx II, designed as a multicentre, open-label, phase III, parallel-arms study, is the first randomized study to compare induction chemotherapy followed by neoadjuvant chemo(re)irradiation and surgery with neoadjuvant chemo(re)irradiation and surgery alone in patients with locally recurrent rectal cancer, with the aim of improving the number of R0 resections
Spread of a SARS-CoV-2 variant through Europe in the summer of 2020.
Following its emergence in late 2019, the spread of SARS-CoV-21,2 has been tracked by phylogenetic analysis of viral genome sequences in unprecedented detail3â5. Although the virus spread globally in early 2020 before borders closed, intercontinental travel has since been greatly reduced. However, travel within Europe resumed in the summer of 2020. Here we report on a SARS-CoV-2 variant, 20E (EU1), that was identified in Spain in early summer 2020 and subsequently spread across Europe. We find no evidence that this variant has increased transmissibility, but instead demonstrate how rising incidence in Spain, resumption of travel, and lack of effective screening and containment may explain the variantâs success. Despite travel restrictions, we estimate that 20E (EU1) was introduced hundreds of times to European countries by summertime travellers, which is likely to have undermined local efforts to minimize infection with SARS-CoV-2. Our results illustrate how a variant can rapidly become dominant even in the absence of a substantial transmission advantage in favourable epidemiological settings. Genomic surveillance is critical for understanding how travel can affect transmission of SARS-CoV-2, and thus for informing future containment strategies as travel resumes. © 2021, The Author(s), under exclusive licence to Springer Nature Limited
Global assessment of marine plastic exposure risk for oceanic birds
Plastic pollution is distributed patchily around the worldâs oceans. Likewise, marine organisms that are vulnerable to plastic ingestion or entanglement have uneven distributions. Understanding where wildlife encounters plastic is crucial for targeting research and mitigation. Oceanic seabirds, particularly petrels, frequently ingest plastic, are highly threatened, and cover vast distances during foraging and migration. However, the spatial overlap between petrels and plastics is poorly understood. Here we combine marine plastic density estimates with individual movement data for 7137 birds of 77 petrel species to estimate relative exposure risk. We identify high exposure risk areas in the Mediterranean and Black seas, and the northeast Pacific, northwest Pacific, South Atlantic and southwest Indian oceans. Plastic exposure risk varies greatly among species and populations, and between breeding and non-breeding seasons. Exposure risk is disproportionately high for Threatened species. Outside the Mediterranean and Black seas, exposure risk is highest in the high seas and Exclusive Economic Zones (EEZs) of the USA, Japan, and the UK. Birds generally had higher plastic exposure risk outside the EEZ of the country where they breed. We identify conservation and research priorities, and highlight that international collaboration is key to addressing the impacts of marine plastic on wide-ranging species
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