Short-term Physiological Effects Research Articles

The effects of endurance trainability phenotype, sex, and interval running training on bone collagen synthesis in adult rats

Bone is influenced by many factors such as genetics and mechanical loading, but the short-term physiological effects of these factors on bone (re)modelling are not well characterised. This study investigated the effects of endurance trainability phenotype, sex, and interval running training (7-week intervention) on bone collagen formation in rats using a deuterium oxide stable isotope tracer method. Bone samples of the femur diaphysis, proximal tibia, mid-shaft tibia, and distal tibia were collected after necropsy from forty-six 9 ± 3-month male and female rats selectively bred for yielding low (LRT) or high (HRT) responses to endurance training. Bone collagen proteins were isolated and hydrolysed, and fractional synthetic rates (FSRs) were determined by the incorporation of deuterium into protein-bound alanine via GC-pyrolysis-IRMS. There was a significant large main effect of phenotype at the femur site (p < 0.001; η2g = 0.473) with HRT rats showing greater bone collagen FSRs than LRT rats. There was a significant large main effect of phenotype (p = 0.008; η2g = 0.178) and a significant large main effect of sex (p = 0.005; η2g = 0.196) at the proximal site of the tibia with HRT rats showing greater bone collagen FSRs than LRT rats, and male rats showing greater bone collagen FSRs compared to female rats. There was a significant large main effect of training at the mid-shaft site of the tibia (p = 0.012; η2g = 0.159), with rats that underwent interval running training having greater bone collagen FSRs than control rats. Similarly, there was a significant large main effect of training at the distal site of the tibia (p = 0.050; η2g = 0.156), with rats in the interval running training group having greater bone collagen FSRs compared to rats in the control group. Collectively, this evidence highlights that bone responses to physiological effects are site-specific, indicating that interval running training has positive effects on bone collagen synthesis at the tibial mid-shaft and distal sites, whilst genetic factors affect bone collagen synthesis at the femur diaphysis (phenotype) and proximal tibia (phenotype and sex) in rats.

Using neural biomarkers to personalize dosing of vagus nerve stimulation

BackgroundVagus nerve stimulation (VNS) is an established therapy for treating a variety of chronic diseases, such as epilepsy, depression, obesity, and for stroke rehabilitation. However, lack of precision and side-effects have hindered its efficacy and extension to new conditions. Achieving a better understanding of the relationship between VNS parameters and neural and physiological responses is therefore necessary to enable the design of personalized dosing procedures and improve precision and efficacy of VNS therapies.MethodsWe used biomarkers from recorded evoked fiber activity and short-term physiological responses (throat muscle, cardiac and respiratory activity) to understand the response to a wide range of VNS parameters in anaesthetised pigs. Using signal processing, Gaussian processes (GP) and parametric regression models we analyse the relationship between VNS parameters and neural and physiological responses.ResultsFirstly, we illustrate how considering multiple stimulation parameters in VNS dosing can improve the efficacy and precision of VNS therapies. Secondly, we describe the relationship between different VNS parameters and the evoked fiber activity and show how spatially selective electrodes can be used to improve fiber recruitment. Thirdly, we provide a detailed exploration of the relationship between the activations of neural fiber types and different physiological effects. Finally, based on these results, we discuss how recordings of evoked fiber activity can help design VNS dosing procedures that optimize short-term physiological effects safely and efficiently.ConclusionUnderstanding of evoked fiber activity during VNS provide powerful biomarkers that could improve the precision, safety and efficacy of VNS therapies.

Immobilisation efficacy of conducted electrical weapons on captive white-tailed deer

Context Wildlife emergencies (e.g. injured animals) often require capture or humane dispatch of animals to resolve the situation. Conducted electrical weapons (CEWs) have the potential to immobilise white-tailed deer (Odocoileus virginianus) for a short duration to avoid potential risks of extended immobilisation (e.g. chemical immobilisation) and increase safety for managers and the public during humane killing by gunshot. Aims To test rapid immobilisation with minimal long-term physiological consequences of CEW immobilisation of white-tailed deer. Methods We arranged five treatment groups of captive deer, including (1) chemical immobilisation with 5-s CEW exposure (n = 5), (2) chemical immobilisation with 15-s CEW exposure (n = 5), (3) 5-s CEW exposure with no chemical immobilisation (n = 10), (4) 15-s CEW exposure with no chemical immobilisation (n = 10) and (5) a control group with no chemical immobilisation or CEW exposure (n = 10). We conducted treatments 1 and 2 to determine short-term physiological effects of CEWs on deer, related to overall welfare. In treatment groups 1 and 2, we sedated deer to collect blood immediately before CEW exposure, and 2 days and 5 days post-exposure for serum biochemical analysis (to measure physiological markers of organ and tissue damage). We observed deer before, during and after treatments to evaluate potential behavioural changes. Key results All deer showed signs of muscle paralysis immediately after exposure to CEW and regained muscle control immediately after the exposure ended. Serum biochemistry results for treatment group 1 and 2 revealed significant increases in creatine kinase (CK) and aspartate aminotransferase (AST) 2 days post-treatment, before returning to pre-exposure concentrations by day 5-post-exposure, suggesting temporary myopathy. By 15-days post-exposure, deer that were only exposed to the CEW had 27 of 39 (69%) remotely fired probes still attached. No long-term behavioural or physiological changes were observed post-treatment. Conclusions Our findings suggest that for immobilisation of white-tailed deer, short-term exposure to a CEW to is a potential alternative to typical capture techniques and can provide sufficient immobilisation to approach and humanely kill deer by gunshot if necessary in wildlife emergencies. Implications As with all capture techniques, trainings and protocols should be developed to ensure the safety of personnel and animals during CEW exposures.

Comparison of mild physiological effects of surgical masks and N95 respirators over 60 min at rest.

Dead-space-associated rebreathing of expired air and heat trapping with use of surgical masks and N95 respirators may underlie anecdotal reports of adverse symptoms associated with medical face barriers. Limited data exist directly comparing the physiological effects of masks and respirators at rest. We assessed the short-term physiological effects of both barrier types over 60 min at rest, including face microclimate temperature, end-tidal gases, and venous blood acid-base variables. We recruited 34 participants into two trials: surgical masks (n = 17) and N95 respirators (n = 17). In a seated position, participants underwent a 10-min baseline without a barrier and then wore a standardized surgical mask or dome-shaped N95 respirator for 60 min, followed by a 10-min washout. We instrumented healthy human participants with a peripheral pulse oximeter ([Formula: see text]) and a nasal cannula connected to a dual gas analyzer for measurement of the pressure of end-tidal [Formula: see text] and [Formula: see text], with an associated temperature probe for face microclimate temperature. Venous (v) blood samples were obtained at baseline and following 60-min mask/respirator wearing to assess [Formula: see text], [HCO3-]v and pHv. Compared with baseline during/following 60 min, temperature, [Formula: see text], [Formula: see text], and [HCO3-]v were mildly but significantly higher, and [Formula: see text] and [Formula: see text] were significantly lower, but [Formula: see text] was unaffected. The magnitude of effects was similar between barrier types. Temperature and [Formula: see text] returned to baseline levels within 1-2 min following removal of the barrier. These mild physiological effects may underlie reports of qualitative symptoms while wearing masks or respirators. However, the magnitudes were mild, not physiologically relevant and reversed immediately with the removal of the barrier.NEW & NOTEWORTHY Anecdotal reports suggest mild physiological effects of wearing surgical masks and/or N95 respirators, including heat trapping and rebreathing of expired air. There are limited data directly comparing the physiological effects of wearing medical barriers at rest. We found that the time course and magnitude of changes to face microclimate temperature, end-tidal gases, and venous blood gases and acid-base variables were mild in magnitude, not physiologically relevant, equivalent between barrier types, and immediately reversible on removal.

PO-01-078 THE ACUTE PHYSIOLOGIC EFFECTS OF OSTEOPATHIC MANIPULATIVE TREATMENT IN PATIENTS WITH CARDIAC IMPLANTABLE ELECTRONIC DEVICES: A RANDOMIZED CONTROLLED TRIAL

Osteopathic manipulative treatment (OMT) is a procedure used to improve physiologic function and maintain homeostasis. OMT modulates the autonomic nervous system (ANS) and augments heart rate variability (HRV) in healthy subjects. The acute physiologic effects of OMT have been reported in patients with heart failure, but not in those with cardiac implantable electronic devices (CIEDs). To assess the short-term physiologic effects of OMT on heart rate, respiratory rate, arterial blood pressure, and HRV in patients with CIEDs. Cardiac patients with CIEDs at an osteopathic medical center were recruited into a randomized controlled trial (ClinicalTrials.gov ID: NCT0400474) and assigned to either OMT or light touch (control) groups. Short-term physiologic data was recorded pre and post intervention (including one minute HRV via photoplethysmography). HRV was calculated using root mean square of successive RR interval differences (RMSSD). Student’s t-test was used to compare groups; p < 0.05. 20 subjects were enrolled (10 OMT/10 control). Table 1 shows physiologic measurements prior to and post intervention. Changes in HR, RR, BP, and SpO2 were no different between groups before and after intervention; OMT HRV decreased by 12.39 + 34.05 ms, whereas control HRV increased by 19.94 + 18.54 ms (p=0.022). There was a significant decrease in HRV in the OMT group, but no difference in the remaining standard physiologic variables. The difference in HRV is opposite of what would be expected, and could be due to the effects of OMT on the ANS, altered cardiac response in this population, and possibly a decrease in ectopy. Further evaluation of CIED data (arrhythmias, HRV and activity level) may be helpful in determining the long-term effects of OMT on cardiac arrhythmia patients.

Postprandial pattern of digestive enzymes and protein turnover in meagre (Argyrosomus regius) juveniles.

After a meal, a sequence of physiological changes occurs in animals in response to digestion, absorption and assimilation of the ingested nutrients. These processes are very important for the aquaculture sector since they will define the efficiency by which food is converted into growth, thus contributing to reduce the production costs and also undigested food in the effluents. Here we investigated the activity of digestive enzymes in the midgut and the protein degradation systems following a single meal to define postprandial patterns of action in hepatic and muscle tissues of meagre juveniles. Fish were fed with a single meal followed by a period of 24h without feed. The activity of several digestive enzymes (α-amylase, trypsin, aminopeptidase, alkaline and acid phosphatases) plus the analysis of key players of the ubiquitin-proteasome (UPS) and autophagy-lysosomal (ALS) systems were examined just before feeding (0h, basal point) and 2, 4, 6, 8 and 24h after food ingestion. Digestion was activated around 4h after food ingestion and nutrients available for protein degradation 2h later. This work provided information about the short-term physiological effects induced by a single meal to support scientists' decision when planning a specific study involving digestion and protein degradation, and also to fish farmers on how to better manage feeding protocols when producing A. regius juveniles. Our results suggested that meagre juveniles, under the experimental conditions used, can be fed every 4h, time when digestion starts, however further studies should be addressed to find the optimal feeding regime for this juvenile species.

The Short-Term Effects and Tolerability of Low-Viscosity Soluble Fibre on Gastroparesis Patients: A Pilot Clinical Intervention Study.

Gastroparesis is a motility disorder that causes severe gastric symptoms and delayed gastric emptying, where the majority of sufferers are females (80%), with 29% of sufferers also diagnosed with Type-1 or Type-2 diabetes. Current clinical recommendations involve stringent dietary restriction and includes the avoidance and minimization of dietary fibre. Dietary fibre lowers the glycaemic index of food, reduces inflammation and provides laxation. Lack of dietary fibre in the diet can affect long-term gastrointestinal health. Our previously published rheological study demonstrated that “low-viscosity” soluble fibres could be a potentially tolerable source of fibre for the gastroparetic population. A randomised controlled crossover pilot clinical study was designed to compare Partially-hydrolysed guar gum or PHGG (test fibre 1), gum Arabic (test fibre 2), psyllium husk (positive control) and water (negative control) in mild-to-moderate symptomatic gastroparesis patients (requiring no enteral tube feeding). The principal aim of the study was to determine the short-term physiological effects and tolerability of the test fibres. In n = 10 female participants, post-prandial blood glucose, gastroparesis symptoms, and breath test measurements were recorded. Normalized clinical data revealed that test fibres PHGG and gum Arabic were able to regulate blood glucose comparable to psyllium husk, while causing far fewer symptoms, equivalent to negative control. The test fibres did not greatly delay mouth-to-caecum transit, though more data is needed. The study data looks promising, and a longer-term study investigating these test fibres is being planned.

How to schedule night shift work in order to reduce health and safety risks.

Objectives:This discussion paper aims to provide scientifically based recommendations on night shift schedules, including consecutive shifts, shift intervals and duration of shifts, which may reduce health and safety risks. Short-term physiological effects in terms of circadian disruption, inadequate sleep duration and quality, and fatigue were considered as possible links between night shift work and selected health and safety risks, namely, cancer, cardio-metabolic disease, injuries, and pregnancy-related outcomes.Method:In early 2020, 15 experienced shift work researchers participated in a workshop where they identified relevant scientific literature within their main research area.Results:Knowledge gaps and possible recommendations were discussed based on the current evidence. The consensus was that schedules which reduce circadian disruption may reduce cancer risk, particularly for breast cancer, and schedules that optimize sleep and reduce fatigue may reduce the occurrence of injuries. This is generally achieved with fewer consecutive night shifts, sufficient shift intervals, and shorter night shift duration.Conclusions:Based on the limited, existing literature, we recommend that in order to reduce the risk of injuries and possibly breast cancer, night shift schedules have: (i) ≤3 consecutive night shifts; (ii) shift intervals of ≥11 hours; and (iii) ≤9 hours shift duration. In special cases – eg, oil rigs and other isolated workplaces with better possibilities to adapt to daytime sleep – additional or other recommendations may apply. Finally, to reduce risk of miscarriage, pregnant women should not work more than one night shift in a week.

Short-Term Physiological Effects of a Very Low-Calorie Ketogenic Diet: Effects on Adiponectin Levels and Inflammatory States.

Adipose tissue is a multifunctional organ involved in many physiological and metabolic processes through the production of adipokines and, in particular, adiponectin. Caloric restriction is one of the most important strategies against obesity today. The very low-calorie ketogenic diet (VLCKD) represents a type of caloric restriction with very or extremely low daily food energy consumption. This study aimed to investigate the physiological effects of a VLCKD on anthropometric and biochemical parameters such as adiponectin levels, as well as analyzing oligomeric profiles and cytokine serum levels in obese subjects before and after a VLCKD. Twenty obese subjects were enrolled. At baseline and after eight weeks of intervention, anthropometric and biochemical parameters, such as adiponectin levels, were recorded. Our findings showed a significant change in the anthropometric and biochemical parameters of these obese subjects before and after a VLCKD. We found a negative correlation between adiponectin and lipid profile, visceral adipose tissue (VAT), C-reactive protein (CRP), and pro-inflammatory cytokines such as tumor necrosis factor-α (TNF-α), which confirmed the important involvement of adiponectin in metabolic and inflammatory diseases. We demonstrated the beneficial short-term effects of a VLCKD not only in the treatment of obesity but also in the establishment of obesity-correlated diseases.

Measures to Promote Rural Healthcare Tourism with a Scientific Evidence-Based Approach.

The present study aimed to evaluate the effects of physical activities on human health in forests in countryside and rural areas. The test experiment was conducted in a countryside forest, whereas the controlled experiment was conducted in an urban area where the study participants resided. A total of 22 participants (aged 20.9 ± 1.3 years) were evaluated in this study. Heart rate variability and salivary cortisol level were used as indices of physiological conditions, and semantic differential method, profile of mood states (POMS), and state-trait anxiety inventory (STAI) were used to evaluate the participants’ emotional states. The participants were asked to walk around forest and urban areas for 15 min. The results were as follows. As compared to the urban area, in the forest area, (1) the power of the high-frequency (HF) component of the heart rate variability (HRV) was significantly higher; (2) low-frequency (LF)/(LF + HF) was significantly lower; (3) salivary cortisol level was significantly lower; (4) the participants felt more comfortable, natural, relaxed, and less anxious and showed higher levels of positive emotions and lower levels of negative emotions. Consequently, walking in the forest area induces relaxing short-term physiological and psychological effects on young people living in urban areas.

A Mixed Methods Pilot Study on the Short-Term Physiological Effects of Vaping and Attitudes Regarding Its Use and Health Effects in Samples of Young Adults.

Vaping is a fairly new and legal way young people are inhaling substances into their lungs. Very little is currently known about the immediate physiological impact or the psychosocial reasons surrounding vape use. This study used a mixed methods approach to (a) understand the short-term physiological implications of vape use compared with people who do not vape and (b) investigate the reasons people choose to vape compared with those who choose not to vape. Twenty-four people participated in the study: 12 self-identified as nonvapers, and 12 self-identified as people who vape. All participants were between 18 and 24 years old. Qualitative analysis suggested people vape because they think it is cool, think it is less risky than smoking, and enjoy the social aspects of vaping. People who choose not to vape are concerned about the unknown health implications, think it is a waste of resources, and are apathetic toward it. Quantitative results revealed statistically significant increases in heart rate and decreases in the percentage of blood oxygenation after 20 minutes of vape use. Blood pressure, respiratory rate, and blood sugar scores did not significantly change after 20 minutes of vape use. Differences in the frequencies of men and women across the two groups were found. Significant differences found for systolic blood pressure, respiratory rate, and pulmonary function test became nonsignificant after controlling for gender. Both long- and short-term effects of vaping need to be further evaluated. The psychosocial reasons why certain people vape whereas others in the same peer group do not also need to be better understood.

Physiologic Effects of Nasal Aspiration and Nasopharyngeal Suctioning on Infants With Viral Bronchiolitis.

There is limited evidence supporting an optimum method for removing mucus from the airways of hospitalized infants with bronchiolitis. This study was designed to evaluate short-term physiologic effects between nasal aspiration and nasopharyngeal suctioning in infants. Sixteen infants requiring hospitalization for supportive management of bronchiolitis were instrumented with transcutaneously measured partial pressure of carbon dioxide ([Formula: see text]) and [Formula: see text] monitoring. Electrical impedance tomography (EIT) was used to estimate changes in inspiratory and end-expiratory lung volume loss and recovery. Subjects were suctioned with both nasal aspiration and nasopharyngeal suctioning methods in a randomized order (8 received nasal aspiration followed by nasopharyngeal suctioning, and 8 received nasophayrgeal suctioning followed by nasal aspiration). Noninvasive gas exchange and EIT measurements were obtained at baseline (pre-suction) and at 10, 20, and 30 min following each suctioning intervention. Sputum mass was obtained following suctioning, and clinical respiratory severity scores, before and after suctioning, were computed. There were no differences in inspiratory EIT (P = .93), change in end-expiratory lung impedance (ΔEELI; P = .53), [Formula: see text] (P = .41), [Formula: see text] (P = .88), heart rate (P = .31), or breathing frequency (P = .15) over the course of suctioning between nasal aspiration and nasopharyngeal suctioning. Sputum mass (P = .14) and clinical respiratory score differences before and after suctioning (P = .59) were not different between the 2 suctioning interventions. Sputum mass was not associated with ΔEELI at 30 min for nasal aspiration (ρ = 0.11, P = .69), but there was a moderate positive association for nasopharyngeal suctioning (ρ = 0.50, P = .048). Infants with viral bronchiolitis appeared to tolerate both suctioning techniques without adverse short-term physiologic effects, as indicated by the unchanged gas exchange and estimated lung volumes (EIT). Nasopharyngeal suctioning recovered 36% more sputum than did nasal aspiration and there was moderate correlation between sputum mass and end-expiratory lung impedance change at 30 minutes post-suction with nasopharyngeal that was not present with nasal aspiration. It is possible that a subset of patients may benefit from one type of suctioning over another. Future research focusing on important outcomes for suctioning patients with bronchiolitis with varying degrees of lung disease severity is needed.

Subtle short-term physiological costs of an experimental augmentation of fleas in wild Columbian ground squirrels.

Parasites affect many aspects of host physiology and behavior, and thus are generally thought to negatively impact host fitness. However, changes in form of short-term parasite effects on host physiological markers have generally been overlooked in favor of fitness measures. Here, we studied flea (Oropsylla idahoensis and Oropsylla opisocroistis tuberculata) parasitism on a natural population of Columbian ground squirrels (Urocitellus columbianus) in Sheep River Provincial Park, AB, Canada. Fleas were experimentally added to adult female U. columbianus at physiologically demanding times, including birth, lactation and weaning of their young. The body mass of adult females, as well as their oxidative stress and immunity were recorded multiple times over the active season under flea-augmented and control conditions. We also measured the prevalence of an internal parasite (Trypanosoma otospermophili). Doubly labeled water (DLW) was intra-peritoneally injected at peak lactation to examine energy expenditure. Effects of parasites on oxidative stress were only observed after offspring were weaned. There was no direct effect of experimentally heightened flea prevalence on energy use. A short-term 24 h mass loss (-17 g) was detected briefly after parasite addition, likely due to U. columbianus preferentially allocating time for grooming. Our parasite augmentation did not strongly affect hosts and suggested that short-term physiological effects were unlikely to culminate in long-term fitness consequences. Columbian ground squirrels appear to rapidly manage parasite costs, probably through grooming.

Effect of Massage on Clinical and Physiological Variables During Muscle Fatigue Task in Participants With Chronic Low Back Pain: A Crossover Study

ObjectiveThe purpose of this study was to determine if a reduction of short-term physiological and clinical effects of muscle fatigue can be seen after a session of massage in nonspecific chronic low back pain (cLBP) individuals and to study the possible association between physiological and clinical changes induced by massage. MethodsThirty-six cLBP individuals participated in 2 experimental sessions. In one session, the Sorenson protocol was preceded by a 30-minute massage, but in the other session, only the Sorenson test was performed by participants. Lumbar paraspinal muscle activity was recorded using surface electromyography, and maximal voluntary contraction force was measured using a load cell. Participants rated their lumbar pain intensity before and after massage and after the Sorensen protocol. A 2-way repeated-measures analysis of variance was conducted to test the effect of massage on both variables for both conditions. Pearson correlation analyses were conducted to determine the linear association between physiological and clinical responses to massage. ResultsResults showed that pain perception was significantly reduced after massage (P = .004) but did not seem to influence pain score increases occurring after the Sorensen protocol. Individuals with a high score of low back pain–related disability showed lower back muscle endurance time (r = -.35). Massage yielded no significant effect on fatigue-related physiological variables. ConclusionThe perception of pain in cLBP individuals was reduced after massage. Although massage yielded some positives clinical effects, they were not explained by a reduction in physiological effect of muscle fatigue.

Short-Term Effects of Normocapnic Hyperpnea and Exercise Training in Patients With Chronic Obstructive Pulmonary Disease: A Pilot Study.

The aim of the study was to evaluate the short-term physiologic effects of respiratory muscle training with normocapnic hyperpnea added to standard exercise training on respiratory muscle endurance/strength and exercise tolerance in patients with chronic obstructive pulmonary disease. The study used a randomized controlled trial. Patients referred for rehabilitation were randomly assigned to 20 sessions (twice daily 5 d/wk) of either normocapnic hyperpnea (group 1, n = 12) or sham maneuvers (group 2, n = 10) in addition to individualized cycle training and abdominal, upper, and lower limb muscle exercise. At baseline and end of study, patients underwent evaluation of respiratory muscle endurance, maximum voluntary ventilation, maximal inspiratory, and expiratory pressures, and 6-min walking distance. After training, a significant improvement was found only for group 1 in respiratory muscle endurance time (by 654 [481] secs versus 149 [216] secs for group 2, P = 0.0108) and maximal inspiratory (group 1: from 81.2 [21.9] cmH2O to 107.6 [23.0] cmH2O, P = 0.018 versus group 2: from 75.4 [13.8] cmH2O to 81.3 [18.9] cmH2O, P = 0.139). The difference between groups for 6-min walking distance, maximum voluntary ventilation, and expiratory pressures was not significant. Short-term normocapnic hyperpnea training added to standard exercise, compared with exercise training alone, improves respiratory muscle endurance and strength but not exercise tolerance in patients with chronic obstructive pulmonary disease.

Assessing the potential for using low-frequency electric deterrent barriers to reduce lake sturgeon (Acipenser fulvescens) entrainment

Given the limited evidence on utilizing low-frequency electrical fields as deterrents to fish, we studied lake sturgeon (Acipenser fulvescens Rafinesque, 1817) behavioural responses and short-term physiological reactions to low-frequency (0.1–50 Hz) low-voltage (0.024–0.3 v) electric fields. Fish from 2 year classes were used as a means of including size considerations in the study. Individuals from both year classes exhibited differing responses to the same electric fields, with smaller, younger fish being more reactive to the electric stimulation of the fields than /older, larger fish. The smaller, younger fish also had reduced weight gain 30 days post experiment compared with fish that were a year older. Short-term physiological effects were observed in the older, larger fish in the form of elevated blood glucose levels. Our results show that individuals can acclimatize to electric fields in a relatively short time period and that larger individuals tend to be less affected by low-frequency/low-voltage electric fields than smaller fish. Testing the utility of electric deterrents in a more realistic riverine setting using pulsating electric field is, therefore, highly recommended to ensure decisions regarding the implementation of low-frequency/low-voltage electric barrier systems to reduce entrainment adequately account for possible sublethal effects on lake sturgeon.

Ivermectin residues disrupt dung beetle diversity, soil properties and ecosystem functioning: An interdisciplinary field study

Ivermectin is the most common endectocide used to control parasites affecting livestock. Short-term physiological and behavioural effects of ivermectin on dung beetles may have long-term consequences for beetle populations and ecosystem functioning. Long-term effects of the use of ivermectin can be estimated by comparing dung assemblages and ecosystem functions in areas with conventional ivermectin-treated livestock and environmentally similar areas in which livestock are not treated with veterinary medical products (organic farming). In this study, we investigated both short-term and long-term effects of the administration of ivermectin on the characteristics of dung beetle assemblages and the services they provided in a protected area (Doñana National Park, SW Spain). We examined short-term dung colonization, dwelling, relocation, and disaggregation rates and the associations between these processes and the key assemblage parameters of species richness, abundance, biomass and functional diversity. Furthermore, we analysed changes in soil physical-chemical properties and processes. Short-term differences were observed in the total amount of dung relocated by dung beetles at different colonization vs. emigration stages, suggesting that dung beetles in this area were affected by the recent treatments of livestock with ivermectin. Moreover, short-term effects could also be responsible for the significant differences in dung spreading rates between sites. Conventional use of ivermectin disrupted ecosystem functioning by affecting species richness, abundance and biomass. The decrease in diversity parameters was related to a reduction in the functional efficiency, which resulted in the long-term accumulation of dung on the ground and considerable changes in soil functionality.

Feasibility and physiological effects of noninvasive neurally adjusted ventilatory assist in preterm infants

BackgroundNoninvasive neurally adjusted ventilator assist (NIV-NAVA) was introduced to our clinical practice via a pilot and a randomized observational study to assess its safety, feasibility, and short-term physiological effects.MethodsThe pilot protocol applied NIV-NAVA to 11 infants on nasal CPAP, high-flow nasal cannula, or nasal intermittent mandatory ventilation (NIMV), in multiple 2- to 4-h periods of NIV-NAVA for comparison. This provided the necessary data to design a randomized, controlled observational crossover study in eight additional infants to compare the physiological effects of NIV-NAVA with NIMV during 2-h steady-state conditions. We recorded the peak inspiratory pressure (PIP), FiO2, Edi, oxygen saturations (histogram analysis), transcutaneous PCO2, and movement with an Acoustic Respiratory Movement Sensor.ResultsThe NAVA catheter was used for 81 patient days without complications. NIV-NAVA produced significant reductions (as a percentage of measurements on NIMV) in the following: PIP, 13%; FiO2, 13%; frequency of desaturations, 42%; length of desaturations, 32%; and phasic Edi, 19%. Infant movement and caretaker movement were reduced by 42% and 27%, respectively. Neural inspiratory time was increased by 39 ms on NIV-NAVA, possibly due to Head’s paradoxical reflex.ConclusionNIV-NAVA was a safe, alternative mode of noninvasive support that produced beneficial short-term physiological effects, especially compared with NIMV.

A review of the potential effects of suspended sediment on fishes: potential dredging-related physiological, behavioral, and transgenerational implications

The long-term effects of sediment exposure on aquatic organisms are poorly understood, yet it is critical for determining threshold effects and exposure limits to mitigate potential impacts with regard to population dynamics. In this paper, we present the current state of knowledge to help consolidate the breadth of information regarding total suspended solids (TSS) thresholds for aquatic species, as well as identify areas where data are lacking. More specifically, we provide the state of the science related to TSS effects on freshwater and estuarine fish including short-term (i.e., physiology and behavior) and long-term effects. Our research indicated that little attention has been given to examining long-term effects, e.g., transgenerational effects, from suspended sediments (SS) on fish populations. Understanding transgenerational effects is paramount to developing and predicting the links between fish condition, survival, populations, and communities. Survival of a local fish population to high sediment loads often translates into short-term physiological and behavioral effects; however, the ramifications of such exposure events are rarely tracked across generations. The majority of studies involving SS effects on fish have focused on exposure and mortality rates of affected fish, deposited eggs, or larvae. We developed a conceptual model that highlighted the interactions between sediment dynamics and fish populations. The model can assist in the formulation of more quantitative-based approaches for modeling these interactions. Future research efforts should focus on developing an understanding of whether environmental disturbances, e.g., dredging, may lead to epigenetic changes that may lead to cascade population effects, and if so, under what circumstances.

Short-term Physiological Effects of Increased Water Intake in a Clinical Setting

Low water intake is associated with long-term adverse health outcomes. Despite this, few studies had examined hydration physiology in the general population, where adequate intake, and not excessive loss, is the primary determinant of hydration. This study sought to evaluate the responsiveness of hydration biomarkers in urine and blood to acute changes in water intake. Key findings were that markers of urine concentration and urine volume change rapidly in response to a change in water intake, whereas plasma osmolality is maintained. Moreover, urine concentration varies as a function of the time of day, with nighttime and morning urine samples being more concentrated than afternoon samples. These results suggest that short, well-timed urine samples, such as those taken in the afternoon, may provide values comparable with 24-hour collections, which are more time-consuming and less convenient.