Onset Of Fatigue Research Articles

Driving Fatigue Onset and Visual Attention: An Electroencephalography-Driven Analysis of Ocular Behavior in a Driving Simulation Task

Attentional deficits have tragic consequences on road safety. These deficits are not solely caused by distraction, since they can also arise from other mental impairments such as, most frequently, mental fatigue. Fatigue is among the most prevalent impairing conditions while driving, degrading drivers’ cognitive and physical abilities. This issue is particularly relevant for professional drivers, who spend most of their time behind the wheel. While scientific literature already documented the behavioral effects of driving fatigue, most studies have focused on drivers under sleep deprivation or anyhow at severe fatigue degrees, since it is difficult to recognize the onset of fatigue. The present study employed an EEG-driven approach to detect early signs of fatigue in professional drivers during a simulated task, with the aim of studying visual attention as fatigue begins to set in. Short-range and long-range professional drivers were recruited to take part in a 45-min-long simulated driving experiment. Questionnaires were used to validate the experimental protocol. A previously validated EEG index, the MDrow, was adopted as the benchmark measure for identifying the “fatigued” spans. Results of the eye-tracking analysis showed that, when fatigued, professional drivers tended to focus on non-informative portions of the driving environment. This paper presents evidence that an EEG-driven approach can be used to detect the onset of fatigue while driving and to study the related visual attention patterns. It was found that the onset of fatigue did not differentially impact drivers depending on their professional activity (short- vs. long-range delivery).

Massage prior to exercise delays the onset of the physical working capacity at the fatigue threshold (PWCFT).

Functional massage (FM) is a soft tissue technique that incorporates non-end range joint movement with tissue compression to treat musculotendinous pain and dysfunction. FM has been associated with promoting neural excitability and neuromuscular efficiency. In clinical practice, FM may be used at the beginning of a treatment session to prepare fibers of the target muscle and surrounding soft tissues for functional activity. The Physical Working Capacity at the Fatigue Threshold (PWC<inf>FT</inf>) uses surface electromyography (EMG) to demarcate between non-fatiguing and fatiguing exercise. To our knowledge, no studies have examined the efficacy of FM when performed prior to an exercise session. The purpose of this study was to determine whether pre-performance FM delays the onset of neuromuscular fatigue. We hypothesized that FM would increase maximal power output as well as PWC<inf>FT</inf> compared to the control condition. Thirteen healthy college-aged men (mean±SEM: age, 24.1±0.5 years; weight, 83.0±3.2 kg; and height, 1.80±0.02 m) ranging from 22 to 28 years-old volunteered for the present study. On two occasions separated by at least 7 days, participants visited the laboratory to perform single-leg knee-extensor ergometer exercise after either receiving 7 min of FM (experimental condition) or no FM (control condition). The results indicated that the onset of neuromuscular fatigue was significantly delayed for the absolute and relative PWC<inf>FT</inf> (~80%) values compared to the control condition. There was no significant mean difference between FM and control for maximal power output. The findings of the present study indicated that FM was effective in delaying neuromuscular fatigue as assessed by PWC<inf>FT</inf>. These findings may be applicable to both athletic and clinical settings as FM prior to exercise may help to prime a target muscle before training.

The pivotal role of positive emotions in maintaining nurses’ trust and preventing pandemic fatigue

Abstract Background Nursing is a challenging profession that demands quick adaptation to changing conditions. The COVID-19 pandemic has placed unprecedented pressure on nursing teams, leading to high-stress levels and uncertainty. This study examines how nurses’ emotional response at the start of the pandemic predicts their trust in the healthcare system and pandemic fatigue after three morbidity waves. Methods This study included collecting self-reported data among Israeli nurses in three time periods: 346 nurses during March-May 2020 (T1), 260 nurses during June-July 2020 (T2), and 91 nurses during February 2022 (T3). Change in the study variables was assessed using repeated-measure ANOVA. Two multiple linear regression models were calculated for trust and pandemic fatigue at T3, with the emotions at T1 and professional seniority as predictors. Results A significant increase in negative emotions was observed between T1 and T2 (M = 2.65, SD = 1.12 and M = 3.20, SD = 1.29 respectively). Furthermore, there was a significant decrease in trust levels between T1 and T3 (M = 4.68, SD = 1.14 and M = 4.07, SD = 1.08 respectively). The regression model for trust was significant, with 20% of the variance explained in it, revealing that higher positive emotions at T1 predicted higher trust at T3. Similarly, the regression model for pandemic fatigue was significant (R2=22%), showing that lower professional seniority and lower positive emotions at T1 were predictors of higher pandemic fatigue at T3. Conclusions During a crisis, nurses may experience intense negative emotions like fear and anxiety. However, positive emotions, such as pride and a sense of mission, are crucial in maintaining their trust and preventing the onset of pandemic fatigue. Healthcare organizations should promote emotional support and provide emotional resources so that nurses can continue to deliver high-quality care even during challenging times. Key messages • During times of crisis, it’s crucial to foster positivity and encourage a sense of pride and accomplishment in nursing staff. • Healthcare organizations must provide emotional support to nursing teams in routine and crisis situations to prevent burnout and maintain trust and long-term functioning.

Comparative Analysis of Linear and Nonlinear sEMG Methods for Detecting Muscle Fatigue During Dynamic Biceps Curls

Muscle fatigue, a key concern in sports science, rehabilitation, and occupational health, influences performance, injury risk, and provides insights into muscle functionality and endurance. Surface electromyography (sEMG) has emerged as a vital tool for non-invasively tracking muscle electrical activity and gauging health. As its application for muscle fatigue assessment grows, identifying the most accurate analytical methods is essential. Current sEMG analyses employ both linear and nonlinear metrics to measure fatigue onset and progression, yet research is ongoing to determine which method is most effective in the context of dynamic contractions. The study was aimed to evaluate the efficacy of established linear and nonlinear methods in measuring muscle fatigue caused by dynamic contractions through surface electromyography (sEMG) signals. A group of twelve healthy individuals completed biceps curls at a consistent pace of one repetition per four seconds, which constituted 75% of their 10-repetition maximum. Concurrently, sEMG signals were captured from the biceps brachii muscle at 1000 Hz. To assess the sEMG signals during the initial, middle, and final sets of 10 repetitions, three linear metrics—mean frequency, median frequency, and spectral moment ratio (SMR)—along with two nonlinear approaches, namely sample entropy and detrended fluctuation analysis (DFA), were utilized. The study's outcomes indicated notable shifts in the SMR values and the two DFA-derived scaling exponents across the exercise sets. These results indicated that SMR, sample entropy, and DFA are effective in gauging muscle fatigue, with sample entropy and DFA demonstrating heightened sensitivity to the fatigue levels when compared to the linear metrics.

Respiratory issues and current management in neuromuscular diseases: a narrative review.

Respiratory care is often embedded as a component of the overlapping management strategies in many patients with neuromuscular disease (NMD). Implementation of respiratory care strategies requires a sensitivity to the nature of the disease, the vulnerability during rapid eye movement (REM) sleep and complicating comorbidities specific to each patient. Care must adjust to progression of the disease as well as the comfort and preferences of the patient. Clinical presentations are usually heterogenous based on the specific NMD and overall course of the disease making diagnosis and respiratory care challenging. The aim of this review was to review the state-of-the-art evidence-based clinical practices and updates in the management of respiratory complications in patients with NMDs. We conducted a search on the PubMed and Medline databases using these keywords: secretions, neuromuscular disease, neuromuscular disorders, non-invasive ventilator, neuromuscular respiratory weakness, respiratory failure. The specified timeframe began from 1980 to 2024. Timely use of non-invasive ventilation and overall respiratory care is most important as emerging evidence shows some benefits with improved mortality in this group of patients. In some settings, comorbid complications that dictate need for airway management and oral diversion may have a more profound impact on mortality than the effectiveness of ventilatory support that are chosen. A multidisciplinary team approach to care has been shown to improve the quality of life and survival in these patients in centers of excellence. Patients should have the ability to access services provided by neurology, pulmonology, speech pathology, sleep medicine, cardiology and respiratory therapy services. The cornerstone for management of respiratory failure and sleep disordered breathing in NMD is non-invasive ventilation (NIV). Initiation of this support and other respiratory cares need to be timely, and patients may have very subtle symptoms during the early stages of the disease which makes it challenging in recognizing the onset of respiratory muscle stress and fatigue. Close attention to these symptoms as well as respiratory and radiologic parameters is essential for appropriate incorporation of these cares.

Hybrid Cooperative Control of Functional Electrical Stimulation and Robot Assistance for Upper Extremity Rehabilitation.

Hybrid systems that integrate Functional Electrical Stimulation (FES) and robotic assistance have been proposed in neurorehabilitation to enhance therapeutic benefits. This study focuses on designing a cooperative controller capable of distributing the required torque for movement between robotic actuation and FES, thereby eliminating the need for time-consuming calibration procedures. The control schema comprises three main blocks: a motion generation block that defines the desired trajectory, a motor control block including both a weight compensation feedforward and a feedback impedance controller, and an FES control block, based on trial-by-trial Iterative Learning Control (ILC), that adjusts the stimulation intensity according to a predefined stimulation waveform. The feedforward motor assistance can be dynamically regulated using an allocation factor. Experiments involving 12 healthy volunteers were conducted using a one-degree-of-freedom elbow testbed. The experimental results showcased the successful integration of Functional Electrical Stimulation (FES) with robotic actuation, ensuring precise trajectory tracking with a Root Mean Square Error (RMSE) below 7°. Notably, allocating more torque to FES led to a 51 % reduction in motor torque. In conditions where FES operated alone, there was poorer tracking performance with an RMSE of 24° and an early onset of muscle fatigue, as evidenced by a reduced number of achieved repetitions. Furthermore, the hybrid approach enabled 100 fatigue-free elbow flexion repetitions, underscoring the effectiveness of cooperative FES-motor control in extending the benefits of FES-induced exercises. This study proposes a flexible approach which can be extended to a multi-degree-of-freedom hybrid system. Furthermore, it underscores the significance of employing a straightforward and adaptable methodology with a rapid calibration procedure, making it easily transferable to clinical applications.

A rare case of drug-induced agranulocytosis: A challenging diagnosis andmanagement approach

Agranulocytosis is a severe adverse drug reaction characterized by a significant decrease in the number of neutrophils, making patientshighly susceptible to infections. I present a rare case of drug-induced agranulocytosis in a 45-year-old male patient who presented witha sudden onset of fever, sore throat, and severe fatigue. Infectious and autoimmune etiologies were ruled out by thorough examinations.A thorough medication history indicated that a new drug for the treatment of hypertension had just been started (chlorthalidone). Thepatient was immediately placed on broad-spectrum antibiotics and granulocyte colony-stimulating factor after the medication wasrapidly stopped. The patient’s neutrophil count gradually increased with prompt management, and he displayed clinical improvement.This instance emphasizes the value of prompt diagnosis and treatment of drug-induced agranulocytosis to avert potentially fatalconsequences.

Research on the Anti-Fatigue Effects and Mechanisms of Arecoline in Sleep-Deprived Mice.

This research aims to estimate the anti-fatigue effects of arecoline and explore its underlying mechanisms using a murine model of central fatigue precipitated by sleep deprivation (SD). Seventy-two male C57BL/6 mice were randomly assigned to six groups: a control group, an SD-induced fatigue model group, a group that received Rhodiola Rosea capsules (2.5 mg/kg), and three arecoline groups, which were administered at low, medium, and high doses (10, 20, and 40 mg/kg, respectively). Following 28 days of continuous administrations, the effects of arecoline on mouse fatigue-related behaviors were assessed by behavioral tests, including grip strength, rotarod performance, and weight-bearing swimming endurance. The release levels of the related biochemical markers were measured by enzyme-linked immunosorbent assays (ELISAs). Western blotting was employed to quantify the expression levels of nuclear factor erythroid 2-related factor (Nrf2), Kelch-like ECH-associated protein 1 (Keap1), heme oxygenase 1 (HO-1), sequestosome-1 (p62), and NADPH quinone oxidoreductase 1 (NQO1) in the gastrocnemius muscle. Arecoline administration notably enhanced grip strength, delayed the onset of fatigue as evidenced by extended latencies in rotarod tests, and increased the duration of weight-bearing swimming in mice. In the elevated plus maze, arecoline obviously decreased both the number of entries and the total distance traveled in the open arms. Arecoline markedly decreased the contents of creatine kinase, blood urea nitrogen, lactate dehydrogenase, triglycerides, and cholesterol in the serum, while it elevated the levels of total testosterone, lactate dehydrogenase, and immunoglobulin G. Furthermore, it significantly increased the activities of superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase in the gastrocnemius muscle, reduced malondialdehyde levels, augmented hippocampal SOD and CAT activity, and elevated glycogen stores in both liver and muscle tissues. Neurotransmitter levels showed significant increases, cytokine levels were markedly reduced, and the expressions of Nrf2, Keap1, NQO1, p62, and HO-1 in brain tissues were significantly upregulated. This study demonstrates that arecoline has anti-fatigue activity, and the specific mechanisms are associated with elevating glucose and lipid metabolism levels, relieving oxidative stress damage, inhibiting neuroinflammatory response, and regulating neurotransmitter levels and the Keap1/Nrf2/HO-1 signaling pathway. The research provides a new direction for arecoline's potential in preventing and improving fatigue.

Robust fatigue markers obtained from muscle synergy analysis.

This study aimed to utilize the nonnegative matrix factorization (NNMF) algorithm for muscle synergy analysis, extracting synergy structures and muscle weightings and mining biomarkers reflecting changes in muscle fatigue from these synergy structures. A leg press exercise to induce fatigue was performed by 11 participants. Surface electromyography (sEMG) data from seven muscles, electrocardiography (ECG) data, Borg CR-10 scale scores, and the z-axis acceleration of the weight block were simultaneously collected. Three indices were derived from the synergy structures: activation phase difference, coactivation area, and coactivation time. The indicators were further validated for single-leg landing. Differences in heart rate (HR) and heart rate variability (HRV) were observed across different fatigue levels, with varying degrees of disparity. The median frequency (MDF) exhibited a consistent decline in the primary working muscle groups. Significant differences were noted in activation phase difference, coactivation area, and coactivation time before and after fatigue onset. Moreover, a significant correlation was found between the activation phase difference and the coactivation area with fatigue intensity. The further application of single-leg landing demonstrated the effectiveness of the coactivation area. These indices can serve as biomarkers reflecting simultaneous alterations in the central nervous system and muscle activity post-exertion.

Game Dynamics in Professional Padel: Shots Per Point, Point Pace and Technical Actions.

This study aimed to determine the distributions of number of shots per point, point duration, point pace and technical actions during the match in professional men and women padel players. A total of 35,145 hits (3239 points; men = 1602 and women = 1637) were analyzed in 20 matches corresponding to quarterfinal, semifinal and final matches of the World Padel Tour 2020 season. The observations were conducted through systematic observation and involved a total of 32 players (16 men and 16 women). Men's points lasted 13.5-14.8 s, comprising 10-11 hits, resulting in a ratio of 0.80 shots per second, with no differences between sets. Women's points lasted longer than men's (14.4 to 16.2 s, p = 0.011) but included a similar number of shots per point, resulting in a lower rhythm of play (0.73-0.75 shots per second, p < 0.001), particularly in the third set (p = 0.004). Volleys, lobs and directs were used in >60% of the points, with a frequency of one to three times per point. Bandejas were used in 50-60% of the points, with a frequency of one to two times per point. Backwalls and flat smashes were used at least once in 30-48% of the points. Selective actions had a greater frequency of use in the third set (i.e., flat smash and smash x3 in women; forehand/backhand volleys and side-wall forehand in men), suggesting occasional changes in the style of play, but likely explained by the onset of fatigue. In conclusion, game volumes, intensity and actions remained broadly similar throughout professional padel matches.

Effect of Paxlovid Treatment During Acute COVID-19 on Long COVID Onset: An EHR-Based Target Trial Emulation from the N3C and RECOVER Consortia.

Preventing and treating post-acute sequelae of SARS-CoV-2 infection (PASC), commonly known as Long COVID, has become a public health priority. In this study, we examined whether treatment with Paxlovid in the acute phase of COVID-19 helps prevent the onset of PASC. We used electronic health records from the National Covid Cohort Collaborative (N3C) to define a cohort of 426,352 patients who had COVID-19 since April 1, 2022, and were eligible for Paxlovid treatment due to risk for progression to severe COVID-19. We used the target trial emulation (TTE) framework to estimate the effect of Paxlovid treatment on PASC incidence. We estimated overall PASC incidence using a computable phenotype. We also measured the onset of novel cognitive, fatigue, and respiratory symptoms in the post-acute period. Paxlovid treatment did not have a significant effect on overall PASC incidence (relative risk [RR] = 0.98, 95% confidence interval [CI] 0.95-1.01). However, it had a protective effect on cognitive (RR = 0.90, 95% CI 0.84-0.96) and fatigue (RR = 0.95, 95% CI 0.91-0.98) symptom clusters, which suggests that the etiology of these symptoms may be more closely related to viral load than that of respiratory symptoms.

Ability of Nicotinamide Riboside to Prevent Muscle Fatigue of Barrows Subjected to a Performance Test.

The objective of this study was to determine the daily dietary nicotinamide riboside (NR) dose required to maximize the delay of subjective muscle fatigue onset. Barrows (N = 100) were assigned to one of five treatments: a conventional swine finishing diet containing 0 (CON), 15 (15NR), 30 (30NR), 45 (45NR) mg·kg body weight-1·d-1 NR, or CON supplemented with 45 mg·kg body weight-1·d-1 NR by drench or cookie dough (DRE). All treatments were administered for the final 11 days of feeding. On supplementation d 10, barrows individually experienced a performance test at 1.09 m/s until they were subjectively exhausted. Wireless electromyography (EMG) sensors were affixed to the biceps femoris (BF), tensor fascia latae (TFL), and semitendinosus (ST) to measure real-time muscle activity. There were no treatment effects for barrow speed (p = 0.57), a tendency for a treatment effect (p = 0.07) for distance, and a treatment effect (p = 0.04) on time to exhaustion. Barrows of the 15NR and DRE treatments had greater (p = 0.05) distances to exhaustion than CON barrows but did not differ from other NR barrows (p > 0.11). Barrows in the 45NR treatment did not differ (p = 0.11) in distance from 30NR barrows but tended to have a greater (p = 0.07) distance compared to CON barrows. All other treatment comparisons did not differ (p > 0.27). Barrows in the DRE treatment moved for longer (p < 0.01) than CON barrows, but all other treatments did not differ from each other (p > 0.15). There was no treatment × period interaction for all muscles' root mean square (RMS) values (p > 0.16), but there were Period effects for all muscles (p < 0.01) and a Treatment effect (p = 0.04) in the TFL. For all muscles, period 4 had greater RMS values than all other periods (p < 0.01), who did not differ from each other (p > 0.29). In the TFL, CON barrows had greater RMS values during the performance test compared to all NR treatments (p < 0.02), who did not differ from each other (p > 0.18). Overall, NR demonstrates potential in being a useful tool in fatigue prevention, but efficient administration of the compound needs further investigation.

Applications of the 3-Min All-Out Exercise Test for Prescribing High-Intensity Interval Training: A Narrative Review on a Decade of Research Progress

ABSTRACT The 3-minute all-out exercise test (3MT) was developed over a decade ago and enables the estimation of time for onset of momentary fatigue for a given speed or power output exceeding critical speed (CS) or critical power (CP), respectively. The 3MT has been validated for conducting high-intensity interval training, used with load carriage prediction and prescription, and validated for shuttle running. These prescriptions are novel because they allow for standardizing exercise intensities relative to metabolic parameters as opposed to a percentage of a given maximum or reserve. Research was identified using leading search engines (e.g., PubMed, Google Scholar, and Research Gate) and citations to similar articles. The objective of this review article was to summarize research that emerged on the CS/CP concept with emphasis on applications since the advent of the 3MT. The review concludes with application of the CS/CP concept to the frequency, intensity, time, and type of exercise for exercise prescription.

Cranial and spinal nerve enhancement in SURF1-associated Leigh syndrome

A 23-month-old boy with poor growth, developmental delay, and hypotonia presented with acute onset of ataxia and fatigue. Magnetic resonance imaging (MRI) of the brain and spinal cord was performed as part of diagnostic work-up. MRI showed bilateral symmetrical lesions in basal ganglia, midbrain, and brainstem consistent with Leigh syndrome. Signal abnormalities were also present within the cervical cord, with enhancement of multiple cranial, spinal, and cauda equina nerve roots. Genetic testing confirmed compound heterozygosity for two pathogenic variants in SURF1 implicated in Leigh syndrome. Whilst nerve root enhancement has been described in other mitochondrial disorders, we believe this is the first published case of both cranial and spinal nerve root enhancement in Leigh syndrome.Graphical

Muscle Changes during Direct Attack under Different Conditions in Elite Wheelchair Fencing.

The main objective of this study was to measure the speed and muscular participation of a direct attack gesture with and without fatigue in a sample of elite wheelchair fencers. The maximal isometric force, gestural speed, and resistance to gestural velocity were estimated in 10 elite performed direct fencers. The results revealed that sitting height and wingspan were important factors in achieving the highest speed, especially in women (r = 0.9; p = 0.07). Other factors, such as the elbow angle where the closed position was better, affected muscle contraction in both categories of athletes (p = 0.01). The onset of fatigue was earlier in category B than in category A, with greater variation in direct attack movement. The results highlight the importance of analyzing direct attacks for the best application of quick force, speed, and muscle participation, as well as identifying the onset of technical deterioration to devise a competitive strategy. These parameters may allow for precise design of conditioning sessions for elite wheelchair shooters.

Incidence and severity of acute radiation induced toxicities among breast cancer patients treated with adjuvant radiotherapy at a major cancer treatment center in Ghana

BackgroundAdjuvant radiotherapy after mastectomy or breast conserving surgery (BCS) is the standard of care for majority of patients with breast cancer. This is however associated with mucosal and epidermal toxicity of organs at risk (OARs). Breast cancer patients are exposed to a plethora of wrong perceptions, misinformation and myths concerning the usefulness and adverse effects of radiotherapy. There is paucity of literature on the incidence and severity of radiation-induced acute toxicities experienced by patients with breast cancer in Ghana. AimTo assess the occurrence and severity of four main acute radiation-induced toxicities among female breast cancer patients treated with external beam radiotherapy at a major cancer treatment centre in Ghana. MethodsData on the occurrence of acute toxicities among patients was collected from patients' medical records, through a semi-structured questionnaire and via weekly clinical assessments. The Common Terminology Criteria for Adverse Events (CTCAE) grading scale (version 4.0) was used to grade the severity of these toxicities. Descriptive and inferential statistics using an independent two-sampled t-test (two-tailed), one-way analysis of variance (ANOVA), Pearson's Chi-square and Fisher's exact tests were performed. ResultsDermatitis, fatigue, pharyngitis, and breast (chest) pain were the radiation toxicities found among the breast cancer patients undergoing treatment on the two machines. The mean predominant radiation doses associated with the onset of dermatitis, fatigue, pharyngitis, and chest pain in the breast cancer patients were 22.32 Gy, 22.48 Gy, 13.59 Gy, and 19.27 Gy respectively for treatment with a statistically significant (p = 0.0173). Radiation dermatitis was the most dominant acute radiation toxicity recorded, and its incidence and severity. The range of Fisher's p-values (0.689–0.999) between the acute radiation toxicities with both machines revealed no statistical significance. ConclusionRadiation dermatitis was the dominant acute toxicity, both in incidence and severity for patients treated. There was no statistical significance in the incidence and severity of acute radiation side effects.

Adjunctive hiking bouts during 8weeks regular sailing training improves cardiorespiratory and muscular responses during hiking emulation in highly trained sailors.

To investigate the effects of 8-week hiking bench training on cardiorespiratory and muscular responses of highly trained sailors during hiking emulation. Twenty-four sailors were assigned into two groups: the hiking bench training group (HTG, n=12) and the control group (CG, n=12). Both groups maintained their regular training with the HTG performed two additional hiking bench training sessions per week for 8weeks, while the CG performed an equivalent duration of on-water sailing training. Physiological responses were assessed by performing four successive 3-min hiking bouts on a sailing emulation ergometer before and after the 8-week training period. Comparing the pretest, both groups exhibited a significant decrease (p<0.05) in the percentage of maximal oxygen uptake (%VO2max) and maximal heart rate (%HRmax); the HTG experienced a greater decrease in %VO2max in bouts 2 and 3. The root mean square (RMS) of rectus femoris (RF), vastus lateralis (VL), rectus abdominis (RA), and external oblique decreased significantly (p<0.05), whereas the mean power frequency (MPF) of RF, VL, and RA exhibited an increasing trend. The RMS of RF and RA in HTG were lower than those in CG in the initial three bouts; VL and EA in HTG were lower than those in CG in bouts 1 and 2 (p<0.05). The MPF of RA in HTG was significantly increased in bouts 2, 3, and 4 (p<0.05). Eight-week hiking bench training could improve hiking economy and the activation of lower limb and trunk muscles delaying the onset of fatigue in sailors.

ENTRECTINIB–INDUCED ACUTE RIGHT HEART FAILURE IN A PATIENT WITH METASTATIC LUNG ADENOCARCINOMA

Abstract We report a case report of a 45–year–old woman with a recent diagnosis of stage IV lung adenocarcinoma (PDL1 60%) with brain metastases, who started entrectinib 600 mg orally once daily. Four days after entrectinib initiation, the patient activated the emergency medical services for acute onset of marked fatigue and hypotension. The ECG performed by the emergency unit showed a marked ST–segment elevation in the infero–lateral leads. Therefore, emergent coronary angiography was performed and no evidence of coronary disease was reported. Subsequently, the patient was admitted to the Coronary Care Unit. Clinical evaluation revealed labile hemodynamics, as the patient presented mental confusion, persistent hypotension (BP 90/50 mmHg) and bradycardia (HR 30 bpm). Laboratory testing showed elevated NT–pro BNP, troponin I and transaminases, normal CRP. The electrocardiogram showed persistent diffuse ST–segment elevation. Transthoracic echocardiogram showed severe dilatation and hypokinesia of the right ventricular (GLS VDx –4.5%), with diastolic “D–shape”, normal left ventricular ejection fraction, no significant valvular disease, circumferential pericardial effusion. Clinical, laboratory and instrumental findings suggested a condition of acute right heart failure. We performed urgent computed tomography pulmonary angiography (CTPA) which resulted negative for acute pulmonary embolism. Hence, supportive therapy with dobutamine, norepinephrine and fluid resuscitation was started, with subsequent hemodynamic stabilization. Since no other etiology was demonstrated by the extensive testing, we attributed the acute right ventricular dysfunction to the recent introduction of entrectinib therapy. Therefore, the drug was discontinued. During the hospitalization we observed a rapid normalization of electrocardiogram and right ventricle function by transthoracic echocardiogram, accompanied by a progressive improvement of laboratory parameters. In order to better define right ventricle function and dimension, the patient underwent cardiac magnetic resonance imaging which showed a normal right ventricle ejection fraction (RV EF 52%), the absence of myocardial edema or late gadolinium enhancement and normal volume of the right ventricle. After six days of hospitalization the patient was discharged. Our case report adds to the limited available literature of cardiac toxicity of entrectinib.

Ergonomic Risk Assessment and Fatigue Analysis During Manual Lifting Tasks in Farming Activities

Introduction: Farming is a physically demanding occupation that puts farmers at risk of musculoskeletal disorders, particularly when frequently performing activities like heavy lifting, which strains the lower back muscles. The present study aimed to assess the ergonomic risk and fatigue during manual lifting tasks pertaining to farming activities. Methods: A study was performed on 20 farmers to analyze the ergonomic risks associated with load lifting through the estimation of the Recommended Weight Limit and Lifting Index using the revised NIOSH lifting equation. The low back compression forces of the participants were estimated using the 3DSSPP software. Surface electromyography was employed to analyze the onset of muscle fatigue during the lifting activity. Results: The results of the study showed a 111.12% increase in the recommended weight limit, a 52.77% reduction in lifting index, and a 28.15% reduction in the low back compression forces for the redesigned lifting technique. The average low-back compression force for the redesigned technique was observed to be well below the back compression design limit of 770 lb. A reduction in the slope of the RMS voltage regression line by 60% and a reduction of 50.23% in the peak spectral power of the sEMG signal, accompanied by a shift in the peak spectral power towards higher frequency region indicated delayed onset of fatigue for the redesigned technique. Conclusion: The outcomes of the study indicated that the ergonomic redesign of the lifting task could significantly reduce the lifting index and alleviate the spinal compression forces well within the back-compression design limit. The redesign was also found to delay the onset of fatigue in the erector spinae muscles.

Neurotoxic pesticides change respiratory parameters in early gill-breathing, but not in skin-breathing life-stages of zebrafish (Danio rerio)

Neurotoxic compounds can interfere with active gill ventilation in fish, which might lead to premature death in adult fish, but not in skin-breathing embryos of zebrafish, since these exclusively rely on passive diffusion across the skin. Regarding lethality, this respiratory failure syndrome (RFS) has been discussed as one of the main reasons for the higher sensitivity of adult fish in the acute fish toxicity test (AFT), if compared to embryos in the fish embryo toxicity test (FET). To further elucidate the relationship between the onset of gill respiration and death by a neurotoxic mode of action, a comparative study into oxygen consumption (MO2), breathing frequency (fv) and amplitude (fampl) was performed with 4 d old skin-breathing and 12 d old early gill-breathing zebrafish. Neurotoxic model substances with an LC50 FET/AFT ratio of > 10 were used: chlorpyrifos, permethrin, aldicarb, ziram, and fluoxetine. Exposure to hypoxia served as a positive control, whereas aniline was tested as an example of a narcotic substance interfering non-specifically with gill membranes. In 12 d old larvae, all substances caused an increase in MO2, fv and partly fampl, whereas effects were minor in 4 d old embryos. An increase of fv in 4 d old embryos following exposure to chlorpyrifos, aldicarb and hypoxia could not be correlated with an increased MO2 and might be attributed either to (1) to the successfully postponed decrease of arterial partial pressure of oxygen (PO2) through support of skin respiration by increased fv, (2) to an unspecific stimulation of the sphincter muscles at the base of the gill filaments, or (3) to the establishment of oxygen sensing for later stages. In gill-breathing 12 d old zebrafish, a concentration-dependent increase of fv was detected for aniline and chlorpyrifos, whereas for aldicarb, fluoxetine and permethrin, a decline of fv at higher substance concentrations was measured, most likely due to the onset of paralysis and/or fatigue of the gill filament sphincter muscles. Since alterations of fv serve to postpone the decrease in arterial PO2 and MO2 increased with decreasing fv, the respiratory failure syndrome could clearly be demonstrated in 12 d old zebrafish larvae. Passive respiration across the skin in zebrafish embryos could thus be confirmed as a probable reason for the lower sensitivity of early life-stages to neurotoxicants. Integration of respiratory markers into existing testing protocols with non-protected developmental stages such as embryos might help to not underestimate the toxicity of early life-stages of fish.