Activation of Mechanoreflex, but not Central Command, Delays Heart Rate Recovery after Exercise in Healthy Men.

This study tested the hypotheses that activation of central command and muscle mechanoreflex during post-exercise recovery delays fast-phase heart rate recovery with little influence on the slow phase. Twenty-five healthy men underwent three submaximal cycling bouts, each followed by a different 5-min recovery protocol: active (cycling generated by the own subject), passive (cycling generated by external force) and inactive (no-cycling). Heart rate recovery was assessed by the heart rate decay from peak exercise to 30 s and 60 s of recovery (HRR30s, HRR60s fast phase) and from 60 s-to-300 s of recovery (HRR60-300s slow phase). The effect of central command was examined by comparing active and passive recoveries (with and without central command activation) and the effect of mechanoreflex was assessed by comparing passive and inactive recoveries (with and without mechanoreflex activation). Heart rate recovery was similar between active and passive recoveries, regardless of the phase. Heart rate recovery was slower in the passive than inactive recovery in the fast phase (HRR60s=20±8vs.27 ±10 bpm, p<0.01), but not in the slow phase (HRR60-300s=13±8vs.10±8 bpm, p=0.11). In conclusion, activation of mechanoreflex, but not central command, during recovery delays fast-phase heart rate recovery. These results elucidate important neural mechanisms behind heart rate recovery regulation.

Stretch-shortening cycle exercise produces acute and prolonged impairments on endurance performance: is the peripheral fatigue a single answer?

OBJECTIVE: This study aimed to verify the acute and prolonged effects of stretch-shortening cycle exercise (SSC) on performance and neuromuscular function following a 4-km cycling time trial (4-km TT). METHODS: On separate days, individuals performed a 4-km TT without any previous exercise (CON), immediately (ACUTE) and 48 h after (PROL) SSC protocol (i.e., 100-drop jumps). Neuromuscular function was measured at baseline SSC (baseline), before (pre-TT) and after (post-TT) 4-km TT. Muscle soreness and inflammatory responses also were assessed. RESULTS: The endurance performance was impaired in both ACUTE (- 2.3 ± 1.8%) and PROL (- 1.8 ± 2.4%) compared with CON. The SSC protocol caused also an acute reduction in neuromuscular function, with a greater decrease in potentiated quadriceps twitch-force (Qtw.pot - 49 ± 16%) and voluntary activation (VA - 6.5 ± 7%) compared for CON and PROL at pre-TT. The neuromuscular function was fully recovered 48 h after SSC protocol. Muscle soreness and IL-10 were elevated only 48 h after SSC protocol. At post-TT, Qtw.pot remained lower in ACUTE (- 52 ± 14%) compared to CON (- 29 ± 7%) and PROL (- 31 ± 16%). CONCLUSION: These findings demonstrate that impairment in endurance performance induced by prior SSC protocol was mediated by two distinct mechanisms, where the acute impairment was related to an exacerbated degree of peripheral and central fatigue, and the prolonged impairment was due to elevated perceived muscle soreness.

Mental fatigue does not alter performance or neuromuscular fatigue development during self-paced exercise in recreationally trained cyclists.

PURPOSE: The purpose of this study was to investigate the effects of mental fatigue, characterized by a subjective feeling of tiredness, on the development of neuromuscular fatigue during a 4-km cycling time trial (4-km TT). METHODS: Eight recreationally trained male cyclists performed a 4-km TT after either performing a prolonged cognitive task (mental fatigue) or after viewing emotionally neutral documentaries (control). The neuromuscular function of the knee extensors was assessed using electrical nerve stimulation at baseline, before (pre-TT), and after (post-TT) the 4-km TT. Rating of perceived exertion (RPE) and physiological variables were periodically measured during 4-km TT. RESULTS: Subjective ratings of fatigue increased significantly only after a prolonged cognitive task (P = 0.022). Neuromuscular function at baseline was similar between conditions and remained unchanged at pre-TT. Time to complete the 4-km TT was similar between control (376 ± 27 s) and mental fatigue (376 ± 26 s). There was no significant difference between conditions for RPE, [Formula: see text], [Formula: see text], and HR throughout the exercise. The 4-km TT-induced similar decrease (from baseline to post-TT) in maximal voluntary contraction (mental fatigue - 11 ± 10%, control - 16 ± 12%), twitch force (mental fatigue - 26 ± 16%, control - 24 ± 17%), and voluntary activation (mental fatigue - 5 ± 7%, control - 3 ± 2%) for both conditions. CONCLUSION: Mental fatigue induced by prolonged cognitive task does not impair performance nor alter the degree of central and peripheral fatigue development during self-paced exercise in recreationally trained cyclists.

Spectrum of germline mutations in smokers and non-smokers in Brazilian non-small-cell lung cancer (NSCLC) patients.

Lung cancer (LC) is a leading cause of cancer-related mortality. Although smoking is the major risk factor, ~15% of all cases occur in never-smokers, suggesting that genetic factors play a role in LC predisposition. Indeed, germline mutations in the TP53 gene predispose to multiple cancer types, including LC. To date, few studies compared the somatic and germline mutational profiles of LC cases by smoking status, and none was reported in Brazilians. Whole-exome sequencing (WES) was performed on two pools (seven smokers and six non-smokers) of tumor-derived DNA using the Illumina HiSeq2000 platform. Files from pools were analyzed separately using Ingenuity®Variant AnalysisTM and Mendel,MD. Validation of all candidate variants was performed by Sanger sequencing. Subsequently, validated mutations were analyzed in germline DNA from the same patients and in ethnically matched controls. In addition, a single recurring Brazilian TP53 germline mutation (R337H) was genotyped in 45 non-small-cell lung cancer patients.Four novel germline variants in the ATAD2, AURKA, PTPRD and THBS1 genes were identified exclusively in smoker patients, and four germline missense variants in PLCD1, RAD52, CP and CDC6 genes were identified solely in non-smokers. There were 4/45 (8.9%) germline carriers of the R337H TP53 mutation. In conclusion, the recurring Brazilian TP53 mutation should be genotyped in all non-small-cell lung cancer in Brazil, regardless of smoking status. Distinct pathogenic mutations and novel sequence variants are detected in Brazilian non-small-cell lung cancer patients, by smoking status. The contribution of these sequence variants to LC pathogenesis remains to be further explored.

High Carbohydrate Diet Induces Faster Final Sprint and Overall 10,000-m Times of Young Runners.

This study analyzed the pacing employed by young runners in 10,000 m time-trials under 3 dietary regimens of different carbohydrate (CHO) intakes. Nineteen boys (13-18 years) ate either their normal CHO diet (56% CHO), high (70% CHO), or low (25% CHO) CHO diets for 48 hr; the boys then performed a 10,000 m run (crossover design). The high CHO diet led to faster final sprint (14.4 ± 2.2 km·h⁻¹) and a better performance (50.0 ± 7.0 min) compared with the low CHO diet (13.3 ± 2.4 km·h⁻¹ and 51.9 ± 8.3 min, respectively, p < .05). However, the final sprint and performance time in the high CHO or low CHO diets were statistically not significantly different from the normal CHO diet (13.8 ± 2.2 km·h⁻¹ and 50.9 ± 7.4 min; p > .05). CHO oxidation rate during the constant load exercise at 65% of VO2max was elevated in high CHO diet (1.05 ± 0.38 g·min⁻¹) compared with low CHO diet (0.63 ± 0.36 g·min⁻¹). The rating of perceived exertion increased linearly throughout the trial, independently of the dietary regimen. In conclusion, the high CHO diet induced higher CHO oxidation rates, increased running speed in the final 400 m and enhanced overall running performance, compared with low CHO.

Spectrum of somatic EGFR, KRAS, BRAF, PTEN mutations and TTF-1 expression in Brazilian lung cancer patients.

Lung cancer is the leading global cause of cancer-related mortality. Inter-individual variability in treatment response and prognosis has been associated with genetic polymorphisms in specific genes: EGFR, KRAS, BRAF, PTEN and TTF-1. Somatic mutations in EGFR and KRAS genes are reported at rates of 15-40% in non-small cell lung cancer (NSCLC) in ethnically diverse populations. BRAF and PTEN are commonly mutated genes in various cancer types, including NSCLC, with PTEN mutations exerting an effect on the therapeutic response of EGFR/AKT/PI3K pathway inhibitors. TTF-1 is expressed in approximately 80% of lung adenocarcinomas and its positivity correlates with higher prevalence of EGFR mutation in this cancer type. To determine molecular markers for lung cancer in Brazilian patients, the rate of the predominant EGFR, KRAS, BRAF and PTEN mutations, as well as TTF-1 expression, was assessed in 88 Brazilian NSCLC patients. EGFR exon 19 deletions (del746-750) were detected in 3/88 (3·4%) patients. Activating KRAS mutations in codons 12 and 61 were noted in five (5·7%) and two (2·3%) patients, respectively. None of the common somatic mutations were detected in either the BRAF or PTEN genes. TTF-1 was overexpressed in 40·7% of squamous-cell carcinoma (SCC). Our findings add to a growing body of data that highlights the genetic heterogeneity of the abnormal EGFR pathway in lung cancer among ethnically diverse populations.

Effect of fat- and carbohydrate-rich diets on metabolism and running performance in trained adolescent boys.

OBJECTIVES: A randomized crossover trial was designed to analyze the impact of a short-term, isoenergetic fat-rich or carbohydrate (CHO)-rich diet on substrate oxidation rates during submaximal exercise and on performance in a 10,000-m running time trial in trained, mid- to late-pubertal boys. METHODS: An incremental test was performed to determine the peak oxygen uptake (VO2peak). After 2 days on a fat-rich (24.2% ±â€Š0.8% CHO, 60.4% ±â€Š0.3% fat, and 15.5% ±â€Š1.0% protein), CHO-rich (69.3% ±â€Š1.2% CHO, 15.9% ±â€Š2.1% fat, and 15.1% ±â€Š1.1% protein), or habitual (56.1% ±â€Š7.0% CHO, 27.5% ±â€Š4.9% fat, and 16.5% ±â€Š4.0% protein) diet, 19 trained adolescent boys (15.2 ±â€Š1.5 years) performed a 10-minute constant run at 65% VO2peak to determine the respiratory exchange ratio (RER) during exercise and 10,000-m running on an outdoor track. RESULTS: During the constant run, the RER and CHO contribution to energy expenditure were lower, and fat contribution higher, in the fat-rich diet than in the CHO-rich diet (P < 0.05), but the results were not different from those of the habitual diet. Performance in the 10,000-m run after consuming CHO- and fat-rich diets was similar to performance after a habitual diet (50.0 ±â€Š7.0, 51.9 ±â€Š8.3, and 50.9 ±â€Š7.4 minutes, respectively), but consuming a CHO-rich diet enhanced performance compared with that after a fat-rich diet (P = 0.03). CONCLUSIONS: These findings indicate that a CHO-rich diet provides additional benefits to 10,000-m running performance in trained adolescent boys compared with a fat-rich diet.

Rare Case of Disseminated Histoplasmosis Mitral Valve Endocarditis in Florida.

BACKGROUND Histoplasma capsulatum is prevalent in the mid-eastern United States and is an environmental fungus that causes human infection by the inhalation of its spores. It is commonly associated with areas containing large amounts of bird excrement and can survive for years in the soil. Only 1% of infected individuals develop disseminated histoplasmosis or Histoplasma endocarditis. CASE REPORT A 61-year-old man with atrial fibrillation had 8 months of fatigue, low-grade fevers, night sweats, and unexplained weight loss presented to the Emergency Department. He worked and lived in Central Florida and although he raised cattle, he denied exposure to birds or bats with regularity. A transesophageal echocardiogram confirmed a sessile echo density on the atrial surface of the mitral valve. His microbial Karius cell-free DNA test from his blood sample was positive for Histoplasma capsulatum, and he was immediately given intravenous liposomal amphotericin for 2 weeks. A tissue valve was used to successfully replace his mitral valve along with a coronary artery bypass and a maze procedure for his persistent atrial fibrillation and atrial flutter. The diagnosis of mitral valve endocarditis from disseminated histoplasmosis was confirmed by pathological analysis, and he was sent home on long-term itraconazole maintenance treatment. CONCLUSIONS Surgical intervention in combination with anti-fungal medication can be a lifesaving intervention for disseminated histoplasmosis. A thorough history is particularly important when evaluating a patient with an unknown infectious source, especially assessing for risk factors, including exposure to environmental factors, workplace, and animals.

Oral Health Literacy and Determinants among an Elderly Community in Portugal.

High average life expectancy has caused an increase in the elderly population and with it arises the need to characterize this population regarding their health and, in particular, their oral health. The purpose of this study was to assess and characterize oral health, oral rehabilitation, oral health literacy, oral health perception and quality of life in a sample of elderly participants of a physical activity program in Portugal. An observational cross-sectional study was designed with a group of 206 individuals. All the individuals were clinically assessed, DMFT, PSR and the plaque index were registered, and a questionnaire was applied in the form of a "face-to-face" interview with questions related to the quality of life related to oral health (GOHAI index and the REALD-30 scale). Of the 206 study participants, 90.3% admit brushing their teeth daily, 6.3% practice daily flossing, and 5.8% had a dental appointment in the last 12 months. Applying the REALD-30 scale, 22.7% have a low level (score 0-14), 43.7% a moderate level (score 15-22) and 33.6% a high level (score 23-29) of oral health literacy. The GOHAI scale reveals that 37.4% have a high self-perception of their oral health. A considerable proportion of the sample studied present a moderate level of oral health literacy. Therefore, educating each person about their oral health when participating in a specific health program and developing proposals for oral health promotion activities should be widely considered as a strategy towards primary prevention. Future oral health literacy sessions should be held in order to improve oral health and quality of life among the community.

Methods of Primary Clinical Prevention of Dental Caries in the Adult Patient: An Integrative Review.

AIM: Preventive approaches to oral health diseases, mainly dental caries, require individual and collective policies. Thus, this review was conducted to identify the primary prevention methods of dental caries in adults to improve oral health at the clinical and community levels. METHODS: This review followed the PICO strategy with the research question: "What are the methods of primary prevention of dental caries, in adults, for improving and maintaining oral health integrating clinical and community-based strategies?" Electronic screening was carried out by two independent reviewers in five databases (MedLine/PubMed, SciELO, Web of Science, Cochrane Library, and LILACS) to find relevant publications between 2015-2022. We applied eligibility criteria for selection of the articles. The following MeSH terms were used: "Primary Prevention"; "Adult"; "Oral Health"; "Dental Caries"; "Fluorides, Topical"; "Fluoride Varnishes"; "Pit and Fissure Sealants"; "Preventive Dentistry". Although the term "Prevention strategy" is not a MeSH descriptor, several correlated terms appeared and were used in the search engines: "Preventative Care", "Disease Prevention, Primary", and "Prevention, Primary". The tool provided by the JBI organization (Joanna Briggs Institute) was used to assess the quality of the included studies. RESULTS: Nine studies were included. Overall, it was found that the main primary prevention methods applied in dentistry in adults are the application of pit and fissure sealants, topical application of fluoride performed in the dental clinic, use of fluoridated toothpaste, mouthwash with chlorhexidine at home, use of xylitol, the recommendation for regular appointments with the dentist, and the need to inform patients about the saliva buffer capacity and adoption of a non-cariogenic diet. For that purpose, preventive policies should be taken to prevent dental caries. These include three major challenges: providing the adult population with more knowledge regarding their oral health, empowering patients through adopting healthy lifestyles, and developing new preventive strategies and awareness campaigns aimed at the adult population to promote proper oral health habits. CONCLUSIONS: A small number of studies were found whose participants were adult patients. There was some consistency regarding primary prevention methods in our studies. However, good quality randomized control studies are still required to define the best intervention strategies for adult caries prevention.

Oral Health Strategies: Surveying the Present to Plan the Future of Community-Based Learning.

Introduction: Oral health literacy relates to the capacity of individuals to acquire, understand and to act upon oral health information to make appropriate health decisions. This scientific review's main goal is to analyze the strategies that improve oral health literacy within the community, specifically oriented to a community-based learning model focused on the most vulnerable risk groups in society. Materials and Methods: The current review is based on the literature on oral health literacy within community-based learning strategies. The present review selected scientific studies by searching MEDLINE and related databases, such as Web of Science and PUBMED, and by consulting existing bibliographies. Results: Based on the application of the inclusion criteria to the abstracts, 45 publications were retrieved which explicitly dealt with the definitions of oral health literacy, community-based learning, and service learning. Several studies have demonstrated that health consumers with low health literacy fail to understand the available health information. Therefore, innovative oral health literacy strategies should be undertaken. Service learning is an example of an educational approach where the student learns specific soft skills in the classroom and collaborates directly with an agency or institution and engages in reflection activities to deepen their understanding of what is being taught. Conclusions: One of the main strategies used to incorporate the oral health professional in social responsibility and direct contact in the community is through experiencing community-based learning projects. The future graduate must be an educator capable of educating patients in order to themselves acquire high-level skills in oral health literacy.

Impact of the COVID-19 Pandemic Period on Patients with Head and Neck Carcinoma: A Systematic Review.

INTRODUCTION: The COVID-19 pandemic has significantly impacted all public life and the global economy. Since its discovery, the disease has spread rapidly, which led to an unprecedented public health crisis and the adoption of extreme measures to limit community and hospital spread. As a result of a confluence of extraordinary circumstances caused by this pandemic, the doctrines of treatment for patients with head and neck carcinoma had to be reanalyzed, guaranteeing the well-being of both patients and health professionals as well as society itself. OBJECTIVE: The aim of our systematic review was to study the impact of the COVID-19 pandemic period on head and neck cancer patients, the effects on the health care provided and on patient health. MATERIALS AND METHODS: This systematic review was based on the PRISMA guidelines and PICO strategy, with the focus question, "How has the COVID-19 pandemic period conditioned the treatment of patients with head and neck carcinoma?" Thus, electronic research was carried out on six databases: LILACS, PubMed/MedLine, Web of Science, the Cochrane COVID-19 Study Register, Scielo, and Scopus, aiming to answer the research question by considering the objective and defined criteria. The following information was extracted: author and year of the publication, patients' age, gender, time until the first appointment, time from the first appointment to the surgery, the period in the hospital, time in intensive care, TNM, general stage of cancer, diagnostic procedures, oncological procedures, reconstructive surgery, and postoperative complications. RESULTS: Initially, 837 articles were found. After removing duplicates, we obtained 471 studies. After screening by title and abstract, 67 articles were selected for full-text reading (k = 92) in order to assess their eligibility. Thus, nine articles were included (k = 1.0). All data and statistical results were obtained and contrasted. The included studies made it possible to reveal distinct impacts felt in different institutions of several countries, not allowing generalizable conclusions to be drawn. However, some of the variables analyzed are worrying, namely, the limitations that occurred in some types of oncological surgeries, as well as the increase in the number of patients admitted with higher TNM classifications and more debilitated general conditions. CONCLUSION: Within the limitation of this review, the results showed efforts made to prevent the pandemic from affecting the healthcare provided. There were no significant differences in days inside the intensive care unit, postoperative complications, and, in most cases, length of stay in the hospital. There were no differences in the number of patients admitted with a history of recurrence or neoadjuvant treatment. However, some variables raise concerns, such as the increase in patients with more advanced stage and TNM classification and a decrease in certain oncological procedures.

Distinct pacing profiles result in similar perceptual responses and neuromuscular fatigue development: Why different "roads" finish at the same line?

The current study analysed the effect of distinct pacing profiles (i.e. U, J, and inverted J) in the perceptual responses and neuromuscular fatigue (NMF) development following a 4-km cycling time trial (TT). Twenty-one cyclists with similar training status were allocated into three different groups based on their pacing profile spontaneously adopted during TT. Rating of perceived exertion (RPE), oxygen uptake (⩒O2) and heart rate (HR) were continuously recorded. NMF was assessed by using isometric maximal voluntary contractions (IMVC), while the central [i.e. voluntary activation (VA)] and peripheral fatigue of knee extensors [i.e. peak torque of potentiated twitches (TwPt)] were evaluated using electrically evoked contractions performed pre and 2 min after the TT. TT performance was not different amongst pacing profiles (U = 377 ± 20 s; J = 392 ± 23 s; J-i = 381 ± 20 s) (all P > 0.05). RPE, ⩒O2 and HR increased similarly throughout the TT regardless the pacing strategy (all P > 0.05). Similarly, IMVC (U = -9.9 ± 8.8; J = -9.6 ± 4.5%; J-i = -13.8 ± 11.3%), VA (U = -2.3 ± 1.7%; J = -5.4 ± 2.2%; J-i = -6.4 ± 4.5%) and TwPt (U = -32.5 ± 12.0%; J = -29.5 ± 8.0%; J-i = -33.6 ± 13.6%) were similar amongst pacing profiles (all P > 0.05). Therefore, endurance athletes with similar training status showed the same perceived responses and NMF development regardless the pacing profile spontaneously adopted. It was suggested that these responses occurred in order to preserve a similar rate of change in systemic responses (i.e. RPE, ⩒O2 and HR) and NMF development, ultimately resulting in same TT performance. HighlightsDifferent pacing profiles resulted in the same performance in a 4-km cycling time trial.The similar performance might be due to achievement of the same sensory tolerance limit.There was no difference for perceptual, metabolic and neuromuscular fatigue responses.

Prior Upper Body Exercise Impairs 4-km Cycling Time-Trial Performance Without Altering Neuromuscular Function.

Purpose: This study investigated the effects of previous exhaustive upper body exercise on performance and neuromuscular fatigue following a 4-km cycling time-trial (4-km TT). Methods: Eight recreational cyclists performed a 4-km TT with (ARMPRE) or without (CONTR) a previous arm-crank maximal incremental test. In each experimental session, neuromuscular fatigue was evaluated with a series of electrically evoked and maximal voluntary isometric contractions (MVC). Oxygen uptake ( V ˙ O2), heart rate, electromyographic muscle activity (EMGRMS) and rating of perceived exertion (RPE) were also recorded throughout the 4-km TT. Results: The average power output during the 4-km TT was reduced (P = .027) for the ARMPRE (299 ± 59 W) group, compared with CONTR (310 ± 59 W) and overall performance in 4-km TT was impaired (P = .021) in ARMPRE (382 ± 28 s) compared with CONTR (376 ± 27 s). The decrease observed in MVC (P = .033) and potentiated peak twitch force (P = .004) at post-TT were similar between the ARMPRE and CONTR conditions (P = .739 and P = .493, respectively). There was no (P = .619) change in voluntary activation at post-TT between conditions. V ˙ O2, EMGRMS and RPE measured throughout the 4-km TT were not significantly different between the conditions (P = .558, P = .558 and P = .940, respectively). The rate of RPE change relative to power output average and heart rate was higher (P = .030 and P = .013, respectively) in ARMPRE (0.031 ± 0.018 AU/W and 168 ± 8 bpm) than CONTR (0.022 ± 0.010 AU/W and 161 ± 7 bpm). Conclusion: These results suggest that impaired performance in ARMPRE was mostly due to pronounced perception of effort rather than neuromuscular fatigue.

Genetic association of the PERIOD3 (PER3) Clock gene with extreme obesity.

BACKGROUND: Obesity has reached epidemic proportions worldwide, affecting life quality and span. Susceptibility to obesity is partly mediated by genetic differences. Indeed, several genes from the clock gene family have already been shown to be intimately associated with obesity in diverse ethnic groups. In the present study, an association between BMI and the rs707467, rs228697 and rs228729 PER3 (Period Circadian Clock 3) polymorphisms in subjects with class II (BMI ≥ 35.0-39.9 kg/m2) and class III obesity (>40 kg/m2, extreme obesity) were carried out using TaqMan real-time PCR. Overall, 259 Brazilian adults were genotyped, of whom 122 had class II or III obesity (BMI ≥ 35.0 kg/m2) and 137 were controls having normal weight (BMI > 18.5 and <24.9 kg/m2). RESULTS: PER3 tag SNP (rs228729) shows a significant association with extreme obesity (1000 permutation p = 0.03 and p = 0.04), for genotype and allele frequency respectively) and a haplotype among the three assessed SNPs (alleles G/T/A, rs228697, rs228729, and rs707467, respectively, 1000 permutation p = 0.03) was significantly more prevalent in the group with obesity. CONCLUSION: This exploratory association study suggests that PER3 rs228729 may be associated with extreme obesity in Brazilian adults, however, replication is needed.

Osteonevus of Nanta: a case report in a combined melanocytic nevus.

Secondary osteoma cutis is a phenomenon that may occur in several conditions. When it occurs in a melanocytic nevus it is named osteonevus of Nanta, an event considered uncommon and characterized by the presence of bone formation adjacent or interposed with melanocytic cells. There are reports of its occurrence in various melanocytic lesions, being more frequently associated with intradermal nevus. We report a case of osteonevus of Nanta in combined nevus, possibly the first description of this association.

Caffeine increases peripheral fatigue in low- but not in high-performing cyclists.

The influence of cyclists' performance levels on caffeine-induced increases in neuromuscular fatigue after a 4-km cycling time trial (TT) was investigated. Nineteen cyclists performed a 4-km cycling TT 1 h after ingesting caffeine (5 mg·kg-1) or placebo (cellulose). Changes from baseline to after exercise in voluntary activation (VA) and potentiated 1 Hz force twitch (Qtw,pot) were used as markers of central and peripheral fatigue, respectively. Participants were classified as "high performing" (HP, n = 8) or "low performing" (LP, n = 8) in accordance with their performance in a placebo trial. Compared with placebo, caffeine increased the power, anaerobic mechanical power, and anaerobic work, reducing the time to complete the trial in both groups (p < 0.05). There was a group versus supplement and a group versus supplement versus trial interaction for Qtw,pot, in which the postexercise reduction was greater after caffeine compared with placebo in the LP group (Qtw,pot = -34% ± 17% vs. -21% ± 11%, p = 0.02) but not in the HP group (Qtw,pot = -22% ± 8% vs. -23% ± 10%, p = 0.64). There was no effect of caffeine on VA, but there was a group versus trial interaction with lower postexercise values in the LP group than in the HP group (p = 0.03). Caffeine-induced improvement in 4-km cycling TT performance seems to come at the expense of greater locomotor muscle fatigue in LP but not in HP cyclists. Novelty Caffeine improves exercise performance at the expense of a greater end-exercise peripheral fatigue in low-performing athletes. Caffeine-induced improvement in exercise performance does not affect end-exercise peripheral fatigue in high-performing athletes. High-performing athletes seem to have augmented tolerance to central fatigue during a high-intensity time trial.

Medically Necessary Orthopaedic Surgery During the COVID-19 Pandemic: Safe Surgical Practices and a Classification to Guide Treatment.

BACKGROUND: Coronavirus disease 2019 (COVID-19) has rapidly evolved as a viral pandemic. Countries worldwide have been affected by the recent outbreak caused by the SARS (severe acute respiratory syndrome)-CoV-2 virus. As with prior viral pandemics, health-care workers are at increased risk. Orthopaedic surgical procedures are common in health-care systems, ranging from emergency to elective procedures. Many orthopaedic surgical procedures are life or limb-saving and cannot be postponed during the COVID-19 pandemic because of potential patient harm. Our goal is to analyze how orthopaedic surgeons can perform medically necessary procedures during the pandemic and to help guide decision-making perioperatively. METHODS: We performed a review of the existing literature regarding COVID-19 and prior viral outbreaks to help guide clinical practice in terms of how to safely perform medically necessary orthopaedic procedures during the pandemic for both asymptomatic patients and high-risk (e.g., COVID-19-positive) patients. We created a classification system based on COVID-19 positivity, patient health status, and COVID-19 prevalence to help guide perioperative decision-making. RESULTS: We advocate that only urgent and emergency surgical procedures be performed. By following recommendations from the American College of Surgeons, the Centers for Disease Control and Prevention, and the recent literature, safe orthopaedic surgery and perioperative care can be performed. Screening measures are needed for patients and perioperative teams. Surgeons and perioperative teams at risk for contracting COVID-19 should use appropriate personal protective equipment (PPE), including N95 respirators or powered air-purifying respirators (PAPRs), when risk of viral spread is high. When preparing for medically necessary orthopaedic procedures during the pandemic, our classification system will help to guide decision-making. A multidisciplinary care plan is needed to ensure patient safety with medically necessary orthopaedic procedures during the COVID-19 pandemic. CONCLUSIONS: Orthopaedic surgery during the COVID-19 pandemic can be performed safely when medically necessary but should be rare for COVID-19-positive or high-risk patients. Appropriate screening, PPE use, and multidisciplinary care will allow for safe medically necessary orthopaedic surgery to continue during the COVID-19 pandemic. LEVEL OF EVIDENCE: Prognostic Level V. See Instructions for Authors for a complete description of levels of evidence.

Characterization of oral health in a Portuguese population with mild intellectual disability.

AIMS: This study aims to characterize the hygiene habits, the self-perception of the need for treatment and the oral condition of a population with a disability. METHODS AND RESULTS: This research is part of an observational, cross-sectional epidemiological study on oral health and quality of life of people with mild intellectual disabilities living in (or attending) institutions of the Central Region of Portugal that were affiliated with HUMANITAS (Portuguese Federation for Mental Disability) in 2016. A sociodemographic and oral health questionnaire, applied on the form of an interview to 240 individuals aged between 18 and 64 years, was used. Statistical analyses were performed using SPSS version 22.0. It was verified that 32.9% of the individuals had less than 20 teeth. Only 15% of all individuals used removable prosthesis. About 21% didn't do oral hygiene daily. Only 28.4% of the sample visited the dentist in the last 6 months. Note that 75.2% of the sample stated their need for dental treatment and less than half (37.4%) described their oral condition as good or superior. CONCLUSION: Dental care among adults with intellectual disability is one of the most unattended health needs. Evidence suggests that inadequate oral health habits are more prevalent in the studied population than in the Portuguese population.