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The facial trauma surgeon will see a variety of facial injuries. Recognition of emergency cases and proper intervention is and this article aims to highlight those cases and the respective proper interventions., (Published by Elsevier Inc.)

Objective: Despite its relatively high prevalence, our understanding of the natural clinical course of acute low-tone hearing loss (ALHL) without vertigo remains incomplete. The purpose of this study is to summarize the findings of studies that evaluated recovery from hearing loss (HL), recurrence and/or fluctuation of HL, and progression to Meniere's Disease (MD) of patients presenting with ALHL without vertigo., Methods: A scoping review of the English literature was performed. On May 14, 2020 and July 6, 2022, MEDLINE, Embase, and Scopus were searched to identify articles related to the prognosis of ALHL. To be included, articles had to present outcomes that were clearly distinguishable for patients with ALHL without vertigo. Two reviewers evaluated articles for inclusion and extracted data. Disagreements were adjudicated by a third reviewer., Results: Forty-one studies were included. There was extensive heterogeneity between studies in regard to defining ALHL, treatment methods, and time of follow-up. Most of the cohorts (39 out of 40) reported partial or complete recovery of hearing in the majority (>50%) of patients, although reports of recurrence were relatively common. Progression to MD was infrequently reported. Shorter time from onset of symptoms to treatment predicted better hearing outcomes in 6 of 8 studies., Conclusion: The literature suggests that although the majority of patients with ALHL experience hearing improvement, recurrence and/or fluctuation are common, and progression to MD occurs in a minority of patients. Additional trials utilizing standardized inclusion and outcome criteria are needed to determine the ideal treatment for ALHL., Level of Evidence: NA Laryngoscope, 133:2457-2469, 2023., (© 2023 The American Laryngological, Rhinological and Otological Society, Inc.)

Objective: The aim of this review article is to discuss the currently available facial fillers, their differences and indications, relevant anatomy, injection techniques, and avoidance and management of complications., Data Sources: Clinical experience and scientific papers., Conclusions: Reversal of facial aging via filler injection has been around since the late 1800s with the initial use of detrimental products. Today, many safe and effective products exist and can be tailored to the individual patient's desired effect. With the evolution of both products and injection techniques, the rate of complications with facial filler use is low. Nonetheless, providers offering facial filler injections should have detailed knowledge of facial anatomy, including facial planes and soft tissue compartments. Multiple injection techniques exist. Different techniques should be used, depending on the anatomic target. Providers should also know how to avoid and manage complications., Competing Interests: The authors declare no conflict of interest., (© 2023 The Authors. World Journal of Otorhinolaryngology ‐ Head and Neck Surgery published by John Wiley & Sons Ltd on behalf of Chinese Medical Association.)

This review article provides an updated discussion on evidence-based practices related to the evaluation and management of facial paralysis. Ultimately, the goals of facial reanimation include obtaining facial symmetry at rest, providing corneal protection, restoring smile symmetry and facial movement for functional and aesthetic purposes. The treatment of facial nerve injury is highly individualized, especially given the wide heterogeneity regarding the degree of initial neuronal insult and eventual functional outcome. Recent advancements in facial reanimation techniques have better equipped clinicians to approach challenging patient scenarios with reliable, effective strategies. We discuss how technology such as machine learning software has revolutionized pre- and post-intervention assessments and provide an overview of current controversies including timing of intervention, choice of donor nerve, and management of nonflaccid facial palsy with synkinesis. We highlight novel considerations to mainstay conservative management strategies and examine innovations in modern surgical techniques with a focus on gracilis free muscle transfer. Innervation sources, procedural staging, coaptation patterns, and multi-vector and multi-muscle paddle design are modifications that have significantly evolved over the past decade., Competing Interests: Declaration of competing interest There are no declarations of interest or competing interests to disclose. This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Objective: The purpose of the present study was to examine the effect of capsiate supplementation on energy intake, self-reported appetite-related sensations, energy expenditure, fat oxidation, and autonomic parameters with and without an exercise intervention., Methods: Thirteen healthy men completed four randomized trials: two trials for the control condition (without exercise), one with capsiate supplementation (CTRL cap ) and one with a placebo (CTRL pla ), and two trials for the exercise condition, one with capsiate supplementation (EX cap ) and one with placebo (EX pla ). Exercise sessions were performed 150 min after the consumption of a standardized breakfast, and supplementation 115 min after consumption of breakfast. An ad libitum buffet was offered 200 min following the completion of the standardized breakfast, and energy intake (EI) and relative energy intake (REI) (relative energy intake = energy intake - energy expenditure related to exercise) were evaluated., Results: There were no significant effects on EI, self-reported appetite sensations, fat oxidation, and energy expenditure. REI was reduced in conditions involving EX when compared to CTRL. A low-frequency to high-frequency ratio for heart rate variability was higher in CTRL cap (1.6 ± 1.1) vs. CTRL pla (1.2 ± 0.9) (p = 0.025; d = 0.39)., Conclusion: Acute capsiate supplementation combined with aerobic exercise has limited effects on the examined variables (EI, REI, fat oxidation, energy expenditure, and autonomic parameters), while changes in the autonomic nervous system function in the absence of exercise may have occurred without influencing other variables., Clinical Trial Registration: ensaiosclinicos.gov.br number, RBR-5pckyr https://ensaiosclinicos.gov.br/rg/RBR-5pckyr.

Abstract: Boffey, D, Clark, NW, and Fukuda, DH. Efficacy of rest redistribution during squats: Considerations for strength and sex. J Strength Cond Res 35(3): 586-595, 2021-This study examined the kinematic, perceptual, and heart rate responses to rest redistribution (RR) and traditional sets (TS) during the barbell back squat for men and women possessing a wide range of strength levels. Forty-five resistance-trained subjects (30 men and 15 women) performed 40 repetitions of the barbell squat with 65% 1RM load with TS (4 × 10 repetitions, 3-minute rest) or RR (10 × 4 repetitions, 1-minute rest), in a randomized order on days separated by ≥72 hours. The significance was set at p ≤ 0.05 for all statistical analyses. The mean velocity (MV) maintenance was significantly higher for RR compared with TS (87.70 ± 4.50% vs. 84.07 ± 4.48%, respectively; p < 0.01, d = 0.35). Rating of perceived exertion (active muscles) was significantly lower for RR compared with TS (5.38 ± 1.42 vs. 6.08 ± 1.43, respectively; p = 0.02, d = -0.35). Rating of perceived exertion (overall) was also significantly lower for RR compared with TS (5.60 ± 1.40 vs. 6.48 ± 1.49, respectively; p = 0.02, d = -0.37). The relative strength ratio (relative strength ratio; squat 1RM: body mass) was significantly correlated with the difference in MV maintenance between RR and TS (r = -0.34, p = 0.02). No sex-based differences (p > 0.05) were found for any dependent variables. Rest redistribution produced significantly higher mean HR (143.25 ± 21.11 vs. 135.05 ± 20.74, p < 0.01) and minimum HR (102.77 ± 19.58 vs. 95.97 ± 22.17, p < 0.01). Subjects were better able to maintain velocity with RR compared with TS, while experiencing less perceived effort. Rest redistribution can be recommended for both men and women, but very strong individuals may not improve their velocity maintenance with RR to the same extent as less strong individuals., (Copyright © 2021 National Strength and Conditioning Association.)

This study examined the cardiac autonomic responses, as measured by heart rate variability (HRV), during cycling exercise and short-term rest after energy drink consumption. Seventeen participants (seven males and 10 females; age: 22.8 ± 3.5 years; BMI: 24.3 ± 3.3 kg/m 2 ) completed this double-blind, placebo-controlled, counterbalanced crossover design study. Participants received an energy drink formula containing 140 mg of caffeine and a placebo in a randomized order before completing a 10-min steady-state warm up (WUP) and a graded exercise test to exhaustion (GXT) followed by a 15-min short-term rest (STR) period. Heartbeat intervals were recorded using a heart rate monitor. Data were divided into WUP, GXT, and STR phases, and HRV parameters were averaged within each phase. Additionally, root mean square of the standard deviation of R-R intervals (RMSSD) during GXT was analyzed to determine the HRV threshold. Separate two-way (sex (male vs. female) x drink (energy drink vs. placebo)) repeated measures ANOVA were utilized. Significant increases in high frequency (HF) and RMSSD were shown during WUP after energy drink consumption, while interactions between drink and sex were observed for HRV threshold parameters (initial RMSSD and rate of RMSSD decline). No significant differences were noted during STR. Energy drink consumption may influence cardiac autonomic responses during low-intensity exercise, and sex-based differences in response to graded exercise to exhaustion may exist.

Post-activation potentiation likely acutely improves power-based performance; however, few studies have demonstrated improved endurance performance. Forty collegiate female rowers performed isometric potentiating (ISO), dynamic potentiating (DYN) and control (CON) warm-up protocols on a rowing ergometer, followed by a three-minute all-out test to evaluate their total distance, peak power, mean power, critical power, anaerobic working capacity (W') and stroke rate. Fifteen-second splits were also analysed. ISO consisted of 5 × 5-second static muscle actions with the ergometer handle rendered immovable with a nylon strap, while DYN consisted of 2 × 10-second all-out rowing bouts, separated by a 2-minute rest interval. The participants were divided into high and low experience groups by median experience level (3.75 years) for statistical analysis. Significant differences (DYN > CON; p < 0.05) were found for distance (+5.6 m), mean power (+5.9 W) and W' (+1561.6 J) for more experienced rowers (n = 19) and no differences for less experienced rowers (n = 18). Mean power in DYN was significantly greater than CON and ISO in the 15-30, 30-45, 45-60 and 60-75 second intervals independent of experience level. These results suggest that DYN may benefit experienced female rowers and that these strategies might benefit a greater power output over shorter distances regardless of experience.

Purpose: The primary purpose of this study was to examine the influence of different work-to-rest ratios on relative energy system utilization during short-term upper-body sprint interval training (SIT) protocols., Methods: Forty-two recreationally trained men were randomized into one of three training groups [10 s work bouts with 2 min of rest (10:2, n = 11) or 4 min of rest (10:4, n = 11), or 30 s work bouts with 4 min of rest (30:4, n = 10)] or a control group (CON, n = 10). Participants underwent six training sessions over 2 weeks with 4-6 'all-out' sprints. Participants completed an upper body Wingate test (30 s 'all-out' using 0.05 kg kg -1 of the participant's body mass) pre- and post-intervention from which oxygen consumption and blood lactate were used to estimate oxidative, glycolytic, and adenosine triphosphate-phosphocreatine (ATP-PCr) energy system provisions. An analysis of covariance was performed on all testing measurements collected at post with the associated pre-values used as covariates., Results: Relative energy contribution (p = 0.026) and energy expenditure (p = 0.019) of the ATP-PCr energy system were greater in 10:4 (49.9%; 62.1 kJ) compared to CON (43.1%; 47.2 kJ) post training. No significant differences were found between groups in glycolytic or oxidative energy contribution over a 30 s upper body Wingate test., Conclusion: SIT protocols with smaller work-to-rest ratios may enhance ATP-PCr utilization in a 30 s upper body Wingate over a 2-week intervention.

Background: Thermogenic fitness drink formulas (TFD) have been shown to increase energy expenditure and markers of lipid metabolism. The purpose of the current study was to compare TFD formulas containing different caffeine concentrations versus a placebo drink on energy expenditure and lipid metabolism at rest and during exercise., Methods: Thirty-two recreationally active participants (22.9 ± 0.7 y, 167.1 ± 1.4 cm, 68.8 ± 2.0 kg, 24.0 ± 1.2% fat) who were regular caffeine consumers, participated in this randomized, double-blind, crossover design study. Participants reported to the laboratory on three occasions, each of which required consumption of either a TFD containing 140 mg or 100 mg of caffeine or a placebo. Baseline measurements of resting energy expenditure (REE) and resting fat oxidation (RFO) were assessed using indirect calorimetry as well as measurements of serum glycerol concentration. Measurements were repeated at 30, 60, 90 min post-ingestion. Following resting measures, participants completed a graded exercise test to determine maximal oxygen uptake (V̇O 2max ), maximal fat oxidation (MFO) and the exercise intensity that elicits MFO (Fat max ), and total energy expenditure (EE)., Results: A significant interaction was shown for REE (p < 0.01) and RFO (p < 0.01). Area under the curve analysis showed an increased REE for the 140 mg compared to the 100 mg formula (p = 0.02) and placebo (p < 0.01) and an increased REE for the 100 mg formula compared to placebo (p = 0.02). RFO significantly decreased for caffeinated formulas at 30 min post ingestion compared to placebo and baseline (p < 0.01) and significantly increased for the 140 mg formula at 60 min post-ingestion (p = 0.03). A main effect was shown for serum glycerol concentrations over time (p < 0.01). No significant differences were shown for V̇O 2max (p = 0.12), Fat max (p = 0.22), and MFO (p = 0.05), and EE (p = 0.08) across drinks., Conclusions: Our results suggest that TFD formulas containing 100 and 140 mg of caffeine are effective in increasing REE and that a 40 mg of caffeine difference between the tested formulas may impact REE and RFO in healthy individuals within 60 min of ingestion.

The purpose of the present study is two-fold. First, we evaluated whether 8-weeks of combined training (high-intensity intermittent plus strength training) may change brain derived neurotropic factor (BDNF) and lipid parameters (triacylglycerol, HDL-c and non-HDL) in a fasted state. Second, we investigated the effect of an acute session of high-intensity intermittent exercise followed by strength training on systemic BDNF and lipid parameters pre- and post 8-weeks of training. Twenty-one healthy and physically active men were divided into two groups: high-intensity intermittent exercise combined with strength training (HSG; n = 11) and control (CG; n = 10). The HSG exercised for one minute at 100% of speedVO 2 max (sVO 2 max) interspersed with one minute of passive recovery followed by strength training (8 exercises with 8-12 repetition maximum loads) for 8-weeks. Heart rate variability, blood pressure, lipid profile, and BDNF concentrations were measured in the fasted state pre- and post-exercise and before and after the 8-week training period. After 8-weeks of exercise training, there was an increase in spectral high frequency component (ms 2 ) and RR interval (p < 0.05), a decreased spectral low frequency component (nu) and heart rate values (p < 0.05), an increase in HDL-c (p < 0.001), and lower BDNF concentrations (p < 0.001). These results suggest that 8-weeks of high-intensity intermittent exercise combined with strength exercise is an effective protective cardio-metabolic strategy capable of increasing HDL-c and BDNF concentrations after an acute exercise session. In the long-term, the modulation on BDNF and HDL-c concentrations may be a determining factor for protection against neurological and cardiovascular diseases.

The objective was to compare the metabolic influence of varying work-to-rest ratios during upper body sprint interval training (SIT). Forty-two recreationally-trained men were randomized into a training group [10 s work - 2 min of rest (10:2) or 4 min of rest (10:4), or 30 s work - 4 min of rest (30:4)] or a control group (CON). Participants underwent six training sessions over two weeks. Assessments consisted of a graded exercise test [maximal oxygen consumption (VO 2 peak) and peak power output (PPO)], four constant-work rate trials [critical power, anaerobic working capacity, and electromyographic fatigue threshold], and an upper body Wingate test (mean/peak power and total work). Post-training absolute and relative VO 2 peak was greater than pre-training for 30:4 (p = .005 and p = .009, respectively), but lower for CON (p = .001 and p = .006, respectively). Post-training PPO was greater in 30:4 (p < .001). No differences were observed during the constant-work rate trials or Wingate test. Traditional SIT appears to have enhanced VO 2 peak in the upper body over a short-term two-week intervention., (Copyright © 2019 Elsevier B.V. All rights reserved.)

The purpose of this study was to compare power outputs of the flying start to the stationary start method on an electromagnetically-braked cycle ergometer. Twenty advanced resistance-trained men (age 24.6 ± 4.5 years; 25.4 ± 2.5 kg/m 2 ) volunteered to participate in this study. A counter-balanced, repeated-measures design was utilized to randomly assign participants to either the flying start or the stationary start for their first Wingate test. Paired t tests were used to evaluate mean differences between start methods. Peak power (PP), mean power (MP), total work (TW), peak cadence (PC), mean cadence (MC), and time to reach peak power (TPP) were recorded. Start method revealed significant differences for PP (p<0.01; flying start = 1,111 ± 42 W vs. stationary start = 854 ± 41 W) and PC attainment (p<0.01; flying start = 167 ± 7 RPM vs. stationary start = 128 ± 5 RPM). Start method did not significantly affect MP (p=0.73; flying start 673 ± 30 W vs. stationary start 657 ± 34 W) or MC (p=0.61; flying start 102 ± 5 RPM vs. 99 ± 4 RPM). The flying start method allowed for not only a greater PP but also a faster TPP (0.24 ± 0.02 seconds). In contrast, TPP was not attained until approximately one-third of the stationary start test (10.3 ± 0.4 seconds). This study showed that the traditional flying start allowed higher PP and PC outputs when compared to the alternative stationary start method in a sample of advanced resistance-trained male participants.

Background/objective: Wintertime thermal inversions in narrow mountain valleys create a ceiling effect, increasing concentration of small particulate matter (PM 2.5 ). Despite potential health risks, many people continue to exercise outdoors in thermal inversions. This study measured the effects of ambient PM 2.5 exposure associated with a typical thermal inversion on exercise performance, pulmonary function, and biological markers of inflammation., Methods: Healthy, active adults (5 males, 11 females) performed two cycle ergometer time trials outdoors in a counterbalanced design: 1) low ambient PM 2.5 concentrations (<12 μg/m 3 ), and 2) an air quality index (AQI) ranking of "yellow." Variables of interest were exercise performance, exhaled nitric oxide (eNO), c-reactive protein (CRP), forced vital capacity (FVC), and forced expiratory volume in 1 s (FEV 1 )., Results: Despite a significant difference in mean PM 2.5 concentration of 9.3 ± 3.0 μg/m 3 between trials ( p  < .001), there was no significant difference ( p  = .424) in the distance covered during low PM 2.5 conditions (9.9 ± 1.7 km) compared to high PM 2.5 conditions (10.1 ± 1.5 km). There were no clinically significant differences across time or between trials for eNO, CRP, FVC, or FEV 1 . Additionally, there were no dose-response relationships ( p  > .05) for PM 2.5 concentration and the measured variables., Conclusion: An acute bout of vigorous exercise during an AQI of "yellow" did not diminish exercise performance in healthy adults, nor did it have a negative effect on pulmonary function or biological health markers. These variables might not be sensitive to small changes from acute, mild PM 2.5 exposure.

Objectives: This study compared an 85-tooth versus the standard 62-tooth chainring for power outputs during a Wingate test using a Velotron electromagnetically-braked cycle ergometer., Design: All participants completed trials using both chainring sizes in a repeated-measures cross-over design., Methods: Resistance-trained male participants (n=20, 24.6±4.5years) performed two Wingate tests separated by at least 48h. Peak power (PP), mean power (MP), fatigue index (FI), peak cadence, mean cadence, and total work (TW) were recorded., Results: Peak power was not significantly different (p=0.10) between trials (62-tooth=1111±187W vs. 85-tooth=1188±103W). However, MP, mean cadence, and TW were significantly greater (p<0.01) for the 85-tooth trial (869±114W, 131±16rpm, and 26,063±3418J) compared to the 62-tooth test (673±136W, 102±24rpm, and 20,199±4066J). Fatigue index was reduced during the 85-tooth trial (49.9±9.1% vs. 61.6±8.8%; p<0.01). Agreement was poor with most ICCs≈0.19 and large SEMs., Conclusions: The two options for chainrings on Velotron cycle ergometers should not be interchangeably used with the Wingate test software; the 62-tooth ring is recommended for most applications. Individuals who can attain peak cadence >180rpm have less variability and tend to achieve higher power outputs on the 62-tooth ring. We suspect that the manufacturer's software limits peak cadence to 182rpm when using the 85-tooth chainring., (Copyright © 2017 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.)

Diabetic retinopathy is a neurovascular diabetes complication resulting in vision loss. A wealth of literature reports retinal molecular changes indicative of neural deficits, inflammation, and vascular leakage with chronic diabetes, but the mechanistic causes of disease initiation and progression are unknown. Microvascular mitochondrial DNA (mtDNA) damage leading to mitochondrial dysfunction has been proposed to drive vascular dysfunction in retinopathy. However, growing evidence suggests that neural retina dysfunction precedes and may cause vascular damage. Therefore, we tested the hypothesis that neural mtDNA damage and mitochondrial dysfunction are an early initiating factor of neural diabetic retinopathy development in a rat streptozotocin-induced, Type I diabetes model. Mitochondrial function (oxygen consumption rates) was quantified in retinal synaptic terminals from diabetic and non-diabetic rats with paired retinal structural and function assessment (optical coherence tomography and electroretinography, respectively). Mitochondrial genome damage was assessed by identifying mutations and deletions across the mtDNA genome by high depth sequencing and absolute mtDNA copy number counting through digital PCR. Mitochondrial protein expression was assessed by targeted mass spectrometry. Retinal functional deficits and neural anatomical changes were present after 3 months of diabetes and prevented/normalized by insulin treatment. No marked dysfunction of mitochondrial activity, maladaptive changes in mitochondrial protein expression, alterations in mtDNA copy number, or increase in mtDNA damage was observed in conjunction with retinal functional and anatomical changes. These results demonstrate that neural retinal dysfunction with diabetes begins prior to mtDNA damage and dysfunction, and therefore retinal neurodegeneration initiation with diabetes occurs through other, non-mitochondrial DNA damage, mechanisms., (© 2017 International Society for Neurochemistry.)

Mitochondria contain multiple copies of the circular mitochondrial genome (mtDNA) that encodes ribosomal RNAs and proteins locally translated for oxidative phosphorylation. Loss of mtDNA integrity, both altered copy number and increased mutations, is implicated in cellular dysfunction with aging. Published data on mtDNA copy number and aging is discordant which may be due to methodological limitations for quantifying mtDNA copy number. Existing quantitative PCR (qPCR) mtDNA copy number quantification methods provide only relative abundances and are problematic to normalize to different template input amounts and across tissues/sample types. As well, existing methods cannot quantify mtDNA copy number in subcellular isolates, such as isolated mitochondria and neuronal synaptic terminals, which lack nuclear genomic DNA for normalization. We have developed and validated a novel absolute mtDNA copy number quantitation method that uses chip-based digital polymerase chain reaction (dPCR) to count the number of copies of mtDNA and used this novel method to assess the literature discrepancy in which there is no clear consensus whether mtDNA numbers change with aging in skeletal muscle. Skeletal muscle in old mice was found to have increased absolute mtDNA numbers compared to young controls. Furthermore, young Sod1 -/- mice were assessed and show an age-mimicking increase in skeletal muscle mtDNA. These findings reproduce a number of previous studies that demonstrate age-related increases in mtDNA. This simple and cost effective dPCR approach should enable precise and accurate mtDNA copy number quantitation in mitochondrial studies, eliminating contradictory studies of mitochondrial DNA content with aging., Competing Interests: Compliance with ethical standards All procedures were approved by the Institutional Animal Care and Use Committee at the Oklahoma Medical Research Foundation. Competing interests The authors declare that they have no competing interests.

This study evaluated the validity and reliability of the BodyMetrix™ BX2000 A-mode ultrasound for estimating percent body fat (%BF) in athletes by comparing it to skinfolds and the BOD POD. Forty-five (22 males, 23 females) National Collegiate Athletic Association (NCAA) Division-I athletes volunteered for this study. Subjects were measured once in the BOD POD then twice by two technicians for skinfolds and ultrasound. A one-way repeated-measures ANOVA revealed significant differences between body composition methods (F = 13.24, p < 0.01, η² = 0.24). This difference was further explained by a sex-specific effect such that the mean difference between ultrasound and BOD POD was large for females (~ 5% BF) but small for males (~ 1.5% BF). Linear regression using the %BF estimate from ultrasound to predict %BF from BOD POD resulted in an R2 = 0.849, SEE = 2.6% BF and a TE = 4.4% BF. The inter-rater intraclass correlation (ICC) for skinfold was 0.966 with a large 95% confidence interval (CI) of 0.328 to 0.991. The inter-rater ICC for ultrasound was 0.987 with a much smaller 95% CI of 0.976 to 0.993. Both skinfolds and ultrasound had test-retest ICCs ≥ 0.996. The BX2000 ultrasound device had excellent test-retest reliability, and its inter-rater reliability was superior to the skinfold method. The validity of this method is questionable, particularly for female athletes. However, due to its excellent reliability, coaches and trainers should consider this portable and easy to use A-mode ultrasound to assess body composition changes in athletes.

Investigations in the 1990s evaluated the influence of breathing assemblies on respiratory variables at rest and during exercise; however, research on new models of breathing assemblies is lacking. This study compared metabolic gas analysis data from a mouthpiece with a noseclip (MOUTH) and a face mask (MASK). Volunteers (7 males, 7 females; 25.1 ± 2.7 years) completed two maximal treadmill tests within 1 week, one MOUTH and one MASK, in random order. The difference in maximal oxygen consumption (VO2max) between MOUTH (52.7 ± 11.3 ml · kg(-1) · min(-1)) and MASK (52.2 ± 11.7 ml · kg(-1) · min(-1)) was not significant (P = 0.53). Likewise, the mean MOUTH-MASK differences in minute ventilation (VE), fraction of expired oxygen (FEO2) and carbon dioxide (FECO2), respiration rate (RR), tidal volume (Vt), heart rate (HR), and rating of perceived exertion (RPE) at maximal and submaximal intensities were not significant (P > 0.05). Furthermore, there was no systematic bias in the error scores (r = -0.13, P = 0.66), and 12 of the 14 participants had a VO2max difference of ≤3 ml · kg(-1) · min(-1) between conditions. Finally, there was no clear participant preference for using the MOUTH or MASK. Selection of MOUTH or MASK will not affect the participant's gas exchange or breathing patterns.

The intestinal absorption of 3-chloro-4-(dichloromethyl)-5-hydroxy-2-[5H] furanone (MX), a highly mutagenic furanone found in chlorinated waters, was studied using an in vitro everted rat gut sac system, using reverse mutation in Salmonella typhimurium to detect mutagens transported from the mucosal to the serosal compartments. Absorption was measurable, but limited, with significant increase in bacterial revertants (serosal compartment) noted at a dose of 50 micrograms/ml MX (mucosal compartment, p < 0.05). Gut sac incubation with MX and glutathione (GSH, 1.0 mM) resulted in no detectable absorption of mutagens. Preincubation with diethylmaleate to deplete mucosal GSH resulted in increased absorption of MX-derived mutagens compared to controls (a significant induction of revertant colonies was noted at a dose of 25 micrograms/ml MX p < 0.05). Gut sac incubation with chlorinated fulvic acids resulted in no detectable absorption of mutagens. In vitro studies to assess the possibility of beta-lyase activation of the postulated MX-GSH conjugate showed no mutagenic activation.

Enzyme mediated hydrolysis of fluazifop butyl has been measured with rat and human skin post-mitochondrial fractions. Rat skin had a ten times greater capacity to metabolise fluazifop butyl than human skin, but the enzyme affinities were similar. The post-mitochondrial fraction metabolism was compared to that seen during absorption in a flow through diffusion cell with viable skin. Limited hydrolysis of absorbed fluazifop butyl was seen in rat skin, but increased two fold if the stratum corneum was removed. The stratum corneum was found to retain fluazifop butyl. When the skin was pre-incubated with the esterase inhibitor bis (p-nitrophenol) phosphate (BNPP), reduced metabolism was seen. No metabolism of fluazifop butyl was seen in human skin during absorption. Retention of the compound by the stratum corneum is postulated to restrict the accessibility of the compound to the enzyme site, thus influencing the observed metabolism during the absorption process.

The effect of oral sodium taurocholate was compared with that of intravenous mannitol when used independently to determine their relative effect on protecting postoperative renal function in patients with obstructive jaundice. A total of 20 patients with obstructive jaundice were randomized to receive either mannitol or sodium taurocholate before surgery. Their preoperative and postoperative renal function was monitored using serum creatinine and predicted creatinine clearance over a 4-day period. There was no difference in postoperative renal function between the two groups and no patient from either group suffered significant renal dysfunction.

In this study we present evidence that lipolysis in man is under beta-2 adrenergic control and that beta-2 stimulation produces a characteristic profile of individual free fatty acid (FFA) release. Twelve healthy volunteers received infusions of placebo (N Saline), terbutaline (a selective beta-2 agonist) and dilevalol (a new non-selective beta-blocker with beta-2 agonist activity). Plasma FFA concentrations during and after the infusions were measured using gas chromatography. A significant rise in total and individual FFAs was seen after 30 min of terbutaline infusion. This was most marked for oleic acid. Total and individual FFA concentrations also rose after 30 min of dilevalol infusion; this was only significant for oleic acid and was approximately 15% of the rise induced by terbutaline infusion. Placebo infusion did not cause any significant changes in FFA levels.

Surface antigens of three stages of the nematode worm Trichinella spiralis has been labelled with iodine and examined by sodium dodecyl sulphate (SDS)/polyacrylamide-gel electrophoresis under reducing and non-reducing conditions. A variety of interactions were defined: the infective larva surface antigens formed a spectrum of aggregates from 50kDa to greater than 1000kDa from subunits of 47kDa and 90kDa; in the adult worms of 60kDa complex arose fron interaction between two dissimilar molecules of 40kDa and 20kDa; the new-born larvae components formed homologous dimers from a 58kDa molecule. Aggregating molecules were adherent to lentil lectin-Sepharose and are therefore glycoproteins. The interactions observed were completely abolished by boiling in SDS/mercaptoethanol, but only partially destroyed by boiling in SDS/iodoacetamide. Based upon this, the associations can be characterized as non-covalent, but disulphide-bond-dependent. It is suggested, but not proved, that the aggregates arise from strong non-covalent hydrophobic interaction sites which are stabilized by intrachain disulphide bonds in the molecules concerned.

Infective larvae, adult males and newborn larvae of Trichinella spiralis were cultured with [35S]methionine in vitro. Total secreted and total somatic (sodium deoxycholate-soluble) proteins were analyzed by electrophoresis in the presence of sodium dodecyl sulphate (SDS-PAGE). Secreted proteins were relatively few in number and were different for each stage, whereas somatic proteins gave an unresolved smear in all cases. Immune precipitation with serum from infected mice revealed only one major antigen in secretions of all stages. In a similar investigation of the solubilised somatic antigens, the complexity of antigens ranged from none in infective larvae, through few in the adult, to many in the newborn larvae. The total concanavalin A-binding glycoproteins of each stage exhibited considerable individuality, and hence stage specificity, when resolved by two dimensional gel analysis. These results extend our knowledge of stage specific components of T. spiralis, and allow a rational approach towards the construction of diagnostic procedures.

A monoclonal antibody (NIM-M7) has been prepared which reacts with a major surface antigen of adult males and females of Trichinella spiralis. This specificity is only demonstrable when the antigen is liberated by detergent solubilization of surface-labelled worms. When reacted with living adults, on the other hand, NIM-M7 reacts well with only the eversible cloaca, or copulatory bell, of the male, binding weakly, if at all, to other surface areas of male or female worms. A similar staining pattern is also given by Concanavalin A. The differential staining given by NIM-M7 must indicate a molecular difference between the organization of the same surface antigen on the cuticular surface of the copulatory bell and other areas of the worm surface. This example of regional specialization demonstrates that the nematode cuticle is not necessarily chemically uniform.

Adult Onchocerca volvulus worms obtained by enzyme digestion from nodules of infected Mexicans were radio-isotope labelled by the chloramine-T or Bolton-Hunter methods. No antigenic determinants were detected in extracts of worms labelled by the chloramine-T method but 3 antigens were detected in extracts of the Bolton-Hunter labelled worms. Two were present in such small amounts that it was impractical to investigate them further, but a major component of mol. wt 20 kDa was purified by gel filtration and used in a serological survey of inhabitants of villages in Southern Mexico. Using the 20 kDa antigen, which is superficially located on both sexes of O. volvulus, sera from both non-endemic and endemic regions were analysed by radio-immunoprecipitation of this antigen. In Southern Mexico, the average sensitivity of the test was 92%, and the specificity 98%. Whilst the 20 kDa antigen did not detect antibodies in the sera of Trinidadians infected with Wuncheria bancrofti or Mansonella ozzardi, this antigen detected high levels of antibodies in Indians exposed to W. bancrofti.

Mice were infected per os with Trichinella spiralis and their lymphocytes were removed and fused with mouse myeloma cell line P3 x 63Ag8653P3 for the selection of monoclonal antibodies to biochemically defined, stage-specific surface antigens of 3 parasite developmental stages: muscle larvae, adults and newborn larvae. Two separate antibodies against a defined single surface antigen of each stage were isolated. In each separate case the pair of monoclonal antibodies precipitated the same component from detergent-solubilized surface antigen preparations, but only one was able to bind to the surface of the living worm. The other must therefore be directed against an antigenic epitope which is obscured in the intact worm surface. The latter type of antibody is unlikely to be involved in the initial phase of parasite rejection and hence is another example of a non-protective host antibody response. The stimulus for its synthesis may be release of surface antigen, which does occur in vitro. One surface antigen of the newborn larvae is only detected by antibody in the first 6 h after birth; thereafter its presence is obscured as other antigens appear. The major surface antigen of the infective larvae contains carbohydrate determinants which are not available at the parasite surface. In addition, it displays great molecular heterogeneity but all variants appear to be derived from a common polypeptide structure.

A method for simultaneous positive and negative selection of cells identified by an antibody is described. It is an adaption of the panning technique using anti-benzene arsonate (Ars)-coated Petri dishes to select the Ars-antibody-coated cells. The adherent cell population is recovered in a suitable state by hapten elution with Ars-azo-tyrosine.

Living, intact protoscoleces of the British horse and sheep strains of Echinococcus granulosus were subjected to surface radioiodination procedures using 125I and Iodogen and 125I-Bolton Hunter reagent. Subsequent combined electron microscopy and autoradiography revealed specific surface membrane labelling with the Iodogen procedure, but significant tegumental labelling with the Bolton-Hunter reagent. The two parasite strains yielded different profiles of electrophoretically separated labelled proteins; the Iodogen method, not surprisingly, resulted in a less complex pattern of labelled polypeptides than the Bolton and Hunter reagent.

Newborn larvae of Trichinella spiralis were collected for 30 min from female worms in culture, incubated in vitro for various times up to 18 h, and surface-labelled with iodine. The detergent-solubilised products were examined by SDS-polyacrylamide gel electrophoresis. At time periods up to 6 h these larvae expressed only one Mr 64 000 iodine-labelled surface protein. Some time between 6 h and 18 h a further three components (apparent Mr 58 000, 34 000 and 32 000) became accessible to surface labelling. All four of these components are antigenic in that they can be immunoprecipitated with T. spiralis immune sera. Tryptic peptide analysis revealed that the 32 and 34 kDa antigens were structurally very similar, but the 58 and 64 kDa proteins differed from each other and the 32-34 kDa pair. Thus T. spiralis not only undergoes a total change in surface antigens between moults, but also major changes in surface antigen expression within one stage.