Changes In Physiological Variables Research Articles

Plasma concentrations of buprenorphine administered via matrix-type transdermal patches applied at three different anatomical locations in healthy adult horses.

Anatomical location-dependent differences in transdermal opioid penetration are well described in human patients. Although this has been investigated in horses with fentanyl, there is no literature available on location-dependent plasma buprenorphine concentrations when administered as a transdermal matrix-type patch. This study aims to compare the plasma concentrations achieved from the matrix-type transdermal buprenorphine patches placed at different anatomical sites (metacarpus, gaskin, and ventral tail base) in healthy adult horses. This is a randomized experimental study with a Latin square design. Six adult horses were given each of three treatments with a minimum 10-day washout period. For each treatment, two 20 μg h-1 matrix-type buprenorphine patches were applied to the ventral aspect of the tail base (TailTDP), metacarpus region (MetacarpusTDP), or gaskin region (GaskinTDP). Whole blood samples (for determination of buprenorphine concentration) and physiological variables were collected before (0 h) and at 0.5, 2, 4, 6, 8, 10, 12, 16, 24, 32, 48, 56, 72, 96 and 120 h after patches were applied. The patches were removed 96 h following placement and were analyzed for residual buprenorphine content. Buprenorphine concentrations were measured in plasma by LC-MS/MS. A mixed-effects model was used to analyze the physiological variables. Between the three treatment groups, there was no change in physiological variables across timepoints as compared to baseline and when compared to each other in a single horse and between horses (p > 0.3). When comparing all three locations, the buprenorphine uptake was observed to be more consistent with respect to measurable plasma concentrations >0.1 ng ml-1 when applied to the ventral aspect of the tail base. In the TailTDP group, the mean plasma buprenorphine concentrations were >0.1 ng ml-1 from 2 to 32 h. The highest group mean was 0.25 ng ml-1 noted at 4 h. The metacarpal and gaskin regions presented more erratic and inconsistent buprenorphine uptake and plasma concentrations as compared to the ventral aspect of the tail base. Further research must be directed at investigating the optimal dose, achievable duration of analgesia, change in measurable plasma concentrations, and behavioral and systemic effects.

Evaluation of physical variables, thermal nociceptive threshold testing and pharmacokinetics during placement of transdermal buprenorphine matrix-type patch in healthy adult horses.

Matrix type transdermal buprenorphine patches have not been investigated in horses and may provide an effective means of providing continuous pain control for extended period and eliminating venous catheterization. Assessment of the physiological variables (heart rate, respiratory rate, body temperature) and thermal nociceptive threshold testing, and describing the pharmacokinetic profile of transdermal buprenorphine matrix-type patch (20 μg h-1 and 40 μg h-1 dosing) in healthy adult horses. Randomised experimental study with a Latin-square design. Six adult healthy horses received each of the three treatments with a minimum 10 day washout period. BUP0 horses did not receive a patch (control). BUP20 horses received one patch (20 μg h-1) applied on the ventral aspect of the tail base resulting in a dose of 0.03-0.04 μg kg-1 h-1. BUP40 horses received two patches placed alongside each other (40 μg h-1) on the tail base resulting in a dose of 0.07-0.09 μg kg-1 h-1. Whole blood samples (for determination of buprenorphine concentration), physiological variables and thermal threshold testing were performed before (0 h) and at 2, 4, 8, 12, 16, 24, 32, 40, 48, 56, 64, 72, and 96 h after patch application. The patches were removed 72 h following placement and were analyzed for residual buprenorphine content. Between the three groups, there was no change in physiological variables across timepoints as compared to baseline (p > 0.1). With the higher dose, there was a significant increase in thermal thresholds from baseline values from 2 h until 48 h and these values were significantly higher than the group receiving the lower patch dose for multiple timepoints up to 40 h. 40 μg h-1 patch led to consistent measurable plasma concentrations starting at 2 h up to 96 h, with the mean plasma concentrations of > 0.1 ng/ml from 4 h to 40 h. 20 μg h-1 and 40 μg h-1 patch doses were well tolerated by all horses. At higher dose, plasma buprenorphine concentrations were more consistently measurable and blunted thermal thresholds for 48 h vs. 32 h with 20 μg h-1 dosing as compared to control.

Differentiation of Hair Sheep Breeds Based on the Physiological and Blood Biochemical Changes in Response to Different Stressors Using Multivariate Analysis Techniques.

Physiological and blood measurement changes due to high heat load, restricted feed intake, and limited drinking water availability in 135 animals of three hair sheep breeds (Dorper, Katahdin, and St. Croix) were subjected to multivariate analysis techniques. The objective of this analysis was to evaluate the ability of these variables to separate individual hair sheep into groups based on adaptation characteristics in response to three physiological stressors and identify variables with greater discriminatory power. There were 16, 8, and 13 physiological and blood variables obtained from high heat load, restricted feed consumption, and water intake studies, respectively, for multivariate analysis. Physiological variables such as respiration rate, rectal and skin temperature, and panting score were measured only in the heat stress study. The results of the cluster and canonical discriminant analyses showed the presence of wide divergence (p < 0.05) between St. Croix and other breeds in their responses to high heat loads and restricted-feed- and -water-intake conditions. Dorper and Katahdin were grouped (p > 0.05) together based on the changes in physiological variables, which were separated (p < 0.05) from those of St. Croix as a resilient group. The stepwise discriminant analysis indicated that skin temperature, panting score, rectal temperature, respiration rate, and blood urea nitrogen and oxygen concentrations were the significant (p < 0.05) discriminating variables in clustering individual sheep into groups based on their responses to the high-heat-stress condition. Under the limited feed intake condition, the significant (p < 0.05) traits responsible for the separation of St. Croix from Dorper and Katahdin were blood triglyceride and cholesterol concentrations, whereas blood hemoglobin, osmolality, protein, and albumin were most important discriminating variables under the limited water intake condition. In conclusion, the results of the present study suggest that the stress responses of Dorper and Katahdin are similar and different from that of St. Croix. This finding can be useful information for future decisions in developing climate-resilient sheep through selective breeding.

Which spontaneous breathing trial to predict effort to breathe after extubation according to five critical illnesses: the cross-over GLOBAL WEAN study protocol

IntroductionReadiness to be freed from ventilatory support can be evaluated by spontaneous breathing trial (SBT) assessing the patient’s ability to sustain respiratory effort after extubation. Current SBT practices are heterogenous...

Monitoring change in heart rate variability following acceptance and commitment therapy for chronic pain: Results of a randomized controlled trial for individuals with neurofibromatosis type 1

Acceptance and Commitment Therapy (ACT) is a well-evidenced therapeutic model for the treatment of chronic pain. While there is substantial data that indicates improvement in the cognitive and behavioral aspects of pain (e.g., pain acceptance, pain inflexibility, pain interference), significantly less research has explored changes in physiological variables following acceptance-based interventions. In particular, heart rate variability (HRV) is a physiological marker of pain and reflects the time elapsed between heart beats. The current study examined whether HRV changed following a randomized-controlled trial of ACT for individuals with neurofibromatosis type 1 and chronic pain (N = 62). Repeated measures analyses of covariance assessed change following ACT. In addition, hierarchical linear regression models examined pain-related predictors of HRV at follow-up. The results suggest that HRV improves following ACT, although given the small sample and limited analytical model, the findings should be considered preliminary. Further, improvements in HRV over the course of the intervention predicted improvements in pain intensity at follow-up suggesting a relationship between these two variables. Taken together, these data provide modest evidence of the relationships between ACT and HRV within a chronic pain population. Additional implications and future directions are discussed.

Efeitos da cetamina, midazolam e metadona, associados à anestesia local, em gatos submetidos à orquiectomia

Different anesthetic combinations are used for orchiectomy in cats. This study aimed to evaluate the anesthetic and cardiopulmonary effects on the physiological variables of ketamine (10 mg/kg), midazolam (0.2 mg/kg) and methadone (0.3 mg/kg), combined with local anesthesia, in cats undergoing orchiectomy (n = 19 cats). The time for lateral recumbency, degree of sedation, muscle relaxation and nociception were recorded preoperatively. The propofol rescue dose was recorded. The time to head up and quality of recovery were evaluated postoperatively. The time for lateral recumbency was 5 ± 2 minu-tes. Fifteen minutes after the administration of the ketamine-midazolam-methadone combination, a greater sedative effect, muscle relaxation and less response to noxious stimulation were observed. Propofol was administered to twelve cats under local anesthesia, at a total dose of 1.5 ± 0.8 mg/kg. Surgery was started 28 ± 5 minutes after the administration of ketamine--midazolam-methadone combination. There were no differences in the physiological variables evaluated over the other evalu-ation times (p &gt; 0.05). The recovery quality scores were adequate, and the time to head up was 51 ± 10 minutes. Under the conditions of this study, the ketamine-midazolam-methadone combination did not allow local anesthesia for orchiectomy. Many cats required propofol rescue prior to surgery. This combination promoted minimal changes in physiological variables and prolonged anesthetic recovery.

Atorvastatin prevents cadmium-induced renal toxicity in a rat model.

In many industrial processes, worker exposure to cadmium causes kidney damage; thus, protection against cadmium toxicity is important in workplace health. Cadmium toxicity involves oxidative stress by increasing the levels of reactive oxygen species. Statins have shown antioxidant effects that might prevent this increase in oxidative stress. We investigated the potential effects of atorvastatin pretreatment in protecting experimental rats against kidney toxicity caused by cadmium. Experiments were performed on 56 adult male Wistar rats (200 ± 20g), randomly assigned to eight groups. Atorvastatin was administered by oral gavage for 15days at 20mg/kg/day, starting 7days before cadmium chloride intra-peritoneal administration (at 1, 2, and 3mg/kg) for 8days. On day 16, blood samples were collected, and kidneys were excised to evaluate the biochemical and histopathological changes. Cadmium chloride significantly increased malondialdehyde, serum creatinine, blood urea nitrogen, and decreased superoxide dismutase, glutathione, and glutathione peroxidase levels. Pre-administration of rats with atorvastatin at a dose of 20mg/kg decreased blood urea nitrogen, creatinine, and lipid peroxidation, increased the activities of antioxidant enzymes, and prevented changes in physiological variables compared with animals that were not pretreated. Atorvastatin pretreatment prevented kidney damage following exposure to toxic doses of cadmium. In conclusion, atorvastatin pretreatment in rats with cadmium chloride-induced kidney toxicity could reduce oxidative stress by changing biochemical functions and thereby decreasing damage to kidney tissue.

Body temperature, heart rate, and locomotor activity measured by bio-loggers before and after a progestogen+eCG treatment for artificial insemination in sheep: effect of pregnancy

Context The introduction of bio-sensors for monitoring real-time changes in physiological variables has helped understand how external factors affect an animal’s resiliency to stressors. Aims To quantify changes in temperature, heart rate, and locomotor activity in ewes during hormonal treatments for artificial insemination (AI) for up to 15 days after insemination. Method Twelve ewes received a surgically implanted subcutaneous bio-logger to record data every 5 min. One week later, ewes received an intravaginal sponge for 12 days and AI was performed 54 ± 1 h after sponge withdrawal. The data were divided into the following four periods: ‘sponge in’ (Days −14 to −2), ‘day before AI’ (Day −1), ‘day AI’ (Day 0), and ‘post-AI’ (Days 1–5, Days 6–10, and Days 11–15). Key results Ewes presented significantly (P &lt; 0.001) higher mean temperature and activity, and a lower heart rate when the sponges were in place than they did in the days following AI. Mean body temperature in the ‘sponge in’ period and the ‘day before AI’, but not in ‘post-AI period’, differed significantly (P &lt; 0.001) between pregnant and non-pregnant ewes. Non-pregnant ewes had a significantly (P &lt; 0.001) higher heart rate than did pregnant ewes when sponges were in and in the ‘post-AI’ period. Non-pregnant ewes were significantly (P &lt; 0.001) less active than were pregnant ewes in the ‘sponge in’ period and on Days 1–5 after AI; however, the former were significantly (P &lt; 0.001) more active than were pregnant ewes on Days 11–15 after AI. Conclusions The subcutaneous bio-logger system documented 24-h variations in body temperature, heart rate, and locomotor activity before and after AI in ewes that had received an estrus-synchronising hormonal treatment. Pregnancy status affected those variables and their circadian fluctuations at the time of the hormonal treatment and in the ‘post-AI’ period. Implications Any device designed for use in the study of Precision Livestock Farming that allows a simple, non-invasive measurement of these variables might provide the basis for the development of a system that could identify females that are in an optimal state for insemination, and provide an early pregnancy prediction system.

Food restriction delays breeding and affects insulin‐like growth factor‐1, oxidative damage and haematocrit value before egg‐laying in female canaries

Environmental challenges, such as fluctuations in food availability, could influence reproductive investment. If resource availability is poor, individuals need to decide in which life‐history process they invest more energy and vital compounds, which determine the cost of reproduction. In resource allocation, the physiological pathways have important roles. The aim of our study was to examine whether food availability influenced physiological traits (insulin‐like growth factor‐1 (IGF‐1) concentration, antioxidant capacity (OXY), level of oxidative damage (ROM) and haematocrit value) prior to egg‐laying in female canaries Serinus canaria. We also tested whether these physiological traits were associated with traits reflecting the reproductive investment in egg macro‐ (egg mass and yolk mass) and micronutrient content (eggshell biliverdin‐ and protoporphyrin‐based colouration). To test these questions we conducted a food restriction experiment with control and food‐restricted (72% of control food) groups. Our study showed that food‐restricted canary females delayed egg‐laying and the physiological traits differed between the groups. At the pre‐laying period, after 9–11 days of treatment, a reduction in plasma IGF‐1 concentration, ROM level and haematocrit value was detected in the control group, whereas in the food‐restricted group plasma IGF‐1 concentration increased, while ROM level and haematocrit value did not change. Plasma level of OXY was not influenced by treatment or breeding period. Plasma concentration of IGF‐1, haematocrit value and oxidative status before egg laying did not affect the egg characteristics. Our study highlights the importance of breeding stage when studying and interpreting the effects of food restriction on physiological traits of breeding birds. Moreover, our data suggest that nutritional limitation had an effect on the timing of egg‐laying that could be mediated by changes in physiological variables.

Respective Impact of Day and Night Bed Baths on Critical Care Patients.

Despite data supporting the reduction of interactions with patients during nighttime, bed bathing is sometimes performed within this period in sedated patients unable to manage their own hygiene care. To compare patient physiologic variables and adverse effect incidence between night and day bed baths. This was a single-center prospective observational study in a 12-bed intensive care unit during 2 months. Night period was defined to run from 10 pm to 6 am. Night bed baths were provided to sedated ventilated patients whatever their sedation, if their Richmond Agitation Sedation Scale score was -2 or deeper. Bed bath-induced changes in physiological variables, treatments, and related unscheduled events were registered during both night and day bed baths. Twenty-one patients (aged 62.9 [52.5-73.2] years, 14 male patients) were included. We registered 97 night bed baths and 95 day bed baths. Heart rate increased only after day bed baths (85 beats/min [bpm] [69-97 bpm] vs 88 bpm [73-98 bpm], P = .02). Increase in Richmond Agitation Sedation Scale score occurred, respectively, during 13 (13.4%) and 8 (8.4%) night and day bed baths, without significant differences. Body temperature significantly decreased during both night and day bed baths (respectively, 37°C [36.6°C-37.4°C] vs 36.6°C [36.2°C-37.2°C], P < .0001; and 36.9°C [36.5°C-37.2°C] vs 36.7°C [36.2°C-37.2°C], P = .0006). Overall, unscheduled events, whether physiologic changes, pain, or calling a physician in rescue occurred in 97 procedures (50.5%), irrespective of their timing (night vs day, respectively 53% [54.6%] vs 44% [46.3%], P = .31). Although unscheduled events occurred in half of bed baths, differences evidenced between nighttime and daytime bed baths were scarce. The appropriateness of nighttime bed bathing remains questionable.

Acute effects of small changes in antero-posterior shoe-cleat position on physiological and biomechanical variables in road cycling

ABSTRACT The aim of this study was to investigate the effect of changes in cycling shoe-cleat position on pedalling biomechanics, physiological variables, and performance in road cycling. Twelve competitive road cyclists performed three pedalling trials with the cleat positioned at the first metatarsal head, 15-mm anterior and 15-mm posterior. Each trial included three sets of 5 min performed at 35%, 50%, and 65% of maximal aerobic power (MAP) followed by a 10-s sprint. Results showed no significant changes in physiological variables, pedalling kinetics, muscular activity of six lower limb muscles, sprint performance and perceived exertion. However, significant differences were found regarding joint kinematics: hip, knee, and ankle angles during both extension and flexion were reduced in the anterior cleat position. Therefore, this study suggests that cleat position does not affect sprint performance, physiological variables, pedalling kinetics, muscle activity, and perceived exertion regardless of the cycling intensity. However, joint kinematics, and particularly knee extension angle which could be related to the risk of overuse injuries, was affected by the shoe-cleat position.

Three-Month FVC Change: A Trial Endpoint for Idiopathic Pulmonary Fibrosis Based on Individual Participant Data Meta-analysis.

Rationale: Novel therapies for idiopathic pulmonary fibrosis (IPF) are in development, but there remains uncertainty about the optimal trial endpoint. An earlier endpoint would enable assessment of a greater number of therapies in adaptive trial designs. Objectives: To determine whether short-term changes in FVC, DlCO, and six-minute-walk distance could act as surrogate endpoints to accelerate early-phase trials in IPF. Methods: Individual participant data (IPD) from IPF clinical trials were included in a two-step random-effects meta-analysis to determine whether baseline or 3-month changes in FVC, DlCO, and 6-minute-walk distance were associated with mortality or disease progression in placebo arms. Three-month and 12-month FVC decline endpoints were compared with treatment arm data from antifibrotic studies by meta-regression. Measurements and Main Results: IPD were available from 12 placebo cohorts totaling 1,819 participants, with baseline and 3-month changes in all physiological variables independently associated with poorer outcomes. Treatment data were available from six cohorts with 1,684 participants. For each 2.5% relative decline in FVC over 3 months, there was an associated 15% (adjusted hazard ratio, 1.15; 95% confidence interval [CI], 1.06-1.24; I2 = 59.4%) and 20% (adjusted hazard ratio, 1.20; 95% CI, 1.12-1.28; I2 = 18.0%) increased risk for mortality in untreated and treated individuals, respectively. An FVC change treatment effect was observed between treatment and placebo arms at 3 months (difference in FVC change of 42.9 ml; 95% CI, 24.0-61.8 ml; P < 0.001). Conclusions: IPD meta-analysis demonstrated that 3-month changes in physiological variables, particularly FVC, were associated with mortality among individuals with IPF. FVC change over 3 months may hold potential as a surrogate endpoint in IPF adaptive trials.

Excessive Erythrocytosis and Chronic Mountain Sickness in the Highest City in the World: A Longitudinal Study

Excessive Erythrocytosis and Chronic Mountain Sickness in the Highest City in the World: A Longitudinal Study

Changes in Physiological Variables in Patients with Diffuse Interstitial Lung Disease in the Six-minute Walk Test

Objective: Diffuse Interstitial Lung Disease (DILD) is a pathology with a high mortality rate in Colombia as well as around the world. Linking patients to pulmonary rehabilitation programs is essential to improve their quality of life and aerobic capacity; thus, all patients perform the six-minute walk test (6-MWT). This study aimed to describe the changes in physiological and aerobic capacity-related variables in patients with DILD in the 6-MWT at admission to a pulmonary rehabilitation program and determine possible differences between patients with idiopathic pulmonary fibrosis (IPF) and other DILDs. Methods: This is a cross-sectional descriptive study on patients with DILD who performed the 6- MWT between January 2017 and February 2019. Sociodemographic, clinical, physiological, and exercise tolerance variables were taken into account at four different times of the 6-MWT: Rest time, the end, and the first and the fifth minute after the end of the test. The Human Ethics Committee endorsed the study, and all participants signed the informed consent form. Results: There were 64 patients with DILD. The average age was 60.84 years, 53.1% were female, 73.4% required home oxygen, and 53.1% had a diagnosis of IPF. There were no statistically significant differences in the heart rate (HR), respiratory rate (RR), peripheral oxygen saturation (SpO2), Borg scale, and fatigue in lower limbs at the four evaluated moments of the test for both groups of patients with DILD (p=0.000); moreover, the FEV1/FVC ratio for patients with other DILD was higher (p=0.000). The distance traveled for IPF was 339.26 ± 124.84, while for other DILDs, it was 365.63 ± 113.00 (p=0.382). Conclusions: Patients with other DILDs have better FEV1/FVC and travel longer distances with less dyspnea and fatigue than patients with IPF during the 6-MWT. Both groups' HR, RR, SpO2, Borg, and fatigue variables presented significant changes during the 6-MWT.

Detrimental or beneficial? Untangling the literature on developmental stress studies in birds.

Developing animals display a tremendous ability to change the course of their developmental path in response to the environment they experience, a concept referred to as developmental plasticity. This change in behavior, physiology or cellular processes is primarily thought to allow animals to better accommodate themselves to the surrounding environment. However, existing data on developmental stress and whether it brings about beneficial or detrimental outcomes show conflicting results. There are several well-referred hypotheses related to developmental stress in the current literature, such as the environmental matching, silver spoon and thrifty phenotype hypotheses. These hypotheses speculate that the early-life environment defines the capacity of the physiological functions and behavioral tendencies and that this change is permanent and impacts the fitness of the individual. These hypotheses also postulate there is a trade-off among organ systems and physiological functions when resources are insufficient. Published data on avian taxa show that some effects of developmental nutritional and thermal stressors are long lasting, such as the effects on body mass and birdsong. Although hypotheses on developmental stress are based on fitness components, data on reproduction and survival are scarce, making it difficult to determine which hypothesis these data support. Furthermore, most physiological and performance measures are collected only once; thus, the physiological mechanisms remain undertested. Here, we offer potential avenues of research to identify reasons behind the contrasting results in developmental stress research and possible ways to determine whether developmental programming due to stressors is beneficial or detrimental, including quantifying reproduction and survival in multiple environments, measuring temporal changes in physiological variables and testing for stress resistance later in life.

Metabolic Energy Contributions During High-Intensity Hatha Yoga and Physiological Comparisons Between Active and Passive (Savasana) Recovery.

Purpose: The objective of this study was to investigate metabolic energy contributions during high-intensity hatha yoga (HIHY) and to compare changes in physiological variables between active and passive recovery methods.Methods: The study involved 20 women yoga instructors (n = 20) who performed 10 min of HIHY (vigorous sun salutation). Upon completion, they were randomly assigned to either active (walking; n = 10) or passive (savasana; n = 10) recovery groups for a period of 10 min. During HIHY, physiological variables such as heart rate (HRpeak and HRmean), oxygen uptake (VO2peak and VO2mean), and blood lactate concentrations (peak La−) were measured. Energetic contributions (phosphagen; WPCR, glycolytic; WGly, and oxidative; WOxi) in kJ and % were estimated using VO2 and La− data. Furthermore, the metabolic equivalents (METs) of VO2peak and VO2mean were calculated. To compare different recovery modes, HRpost, ΔHR, VO2post, ΔVO2, recovery La−, and recovery ΔLa− were analyzed.Results: The results revealed that HRpeak, VO2peak, and peak La− during HIHY showed no differences between the two groups (p > 0.05). Values of HRpeak, HRmean, METs of VO2peak and VO2mean, and La− during HIHY were 95.6% of HRmax, 88.7% of HRmax, 10.54 ± 1.18, 8.67 ±.98 METs, and 8.31 ± 2.18 mmol·L−1, respectively. Furthermore, WOxi was significantly higher compared with WPCR, WGly, and anaerobic contribution (WPCR + WGly), in kJ and % (p < 0.0001). VO2post and recovery ΔLa− were significantly higher in the active recovery group (p < 0.0001, p = 0.0369, respectively). Values of ΔVO2 and recovery La− were significantly lower in the active group compared with the passive group (p = 0.0115, p = 0.0291, respectively).Conclusions: The study concluded that high-intensity hatha yoga which was performed for 10 min is a suitable option for relatively healthy people in the modern workplace who may have hatha yoga experience but do not have time to perform a prolonged exercise. Following active recovery, they can participate in further HIHY sessions during short breaks. Furthermore, a faster return to work can be supported by physiological recovery.

Safety and Efficacy of 23.4% Sodium Chloride Administered via Peripheral Venous Access for the Treatment of Cerebral Herniation and Intracranial Pressure Elevation.

Sodium chloride (NaCl) 23.4% solution has been shown to reduce intracranial pressure (ICP) and reverse transtentorial herniation. A limitation of 23.4% NaCl is its high osmolarity (8008mOsm/l) and the concern for tissue injury or necrosis following extravasation when administered via peripheral venous access. The use of this agent is therefore often limited to central venous or intraosseous routes of administration. Our objective was to evaluate the safety and efficacy of administration of 23.4% NaCl via peripheral venous access compared with administration via central venous access. We reviewed pharmacy records to identify all administrations of 23.4% NaCl at our institution between December 2017 and February 2020. Medical records were then reviewed to identify complications, such as extravasation, soft tissue injury or necrosis, hypotension (mean arterial pressure less than 65mm Hg), pulmonary edema, hemolysis, and osmotic demyelination. We also compared the change in physiological variables, such as ICP, mean arterial pressure, cerebral perfusion pressure, and heart rate, as well as laboratory values, such as sodium, chloride, bicarbonate, creatinine, and hemoglobin, following administration of 23.4% NaCl via the peripheral and central venous routes. We identified 299 administrations of 23.4% NaCl (242 central and 57 peripheral) in 141 patients during the study period. There was no documented occurrence of soft tissue injury or necrosis in any patient. One patient developed hypotension following central administration. Among the 38 patients with ICP monitoring at the time of drug administration, there was no significant difference in median ICP reduction (- 13mm Hg [central] vs. - 24mm Hg [peripheral], p = 0.21) or cerebral perfusion pressure augmentation (16mm Hg [central] vs. 15mm Hg [peripheral], p = 0.87) based on route of administration. Peripheral venous administration of 23.4% NaCl is safe and achieves a reduction in ICP equivalent to that achieved by administration via central venous access.

Mental Fatigue From Smartphone Use Reduces Volume-Load in Resistance Training: A Randomized, Single-Blinded Cross-Over Study.

We investigated the acute effects of mental fatigue induced by 30-minute use of smartphone social network apps on volume load in resistance training among recreationally trained adults. Sixteen (n = 16) adults of both sexes performed three sets of a half back-squat exercise to failure with 80% of 15RM, interspersed with 3-minutes of passive recovery between sets, before and after two different cognitive tasks: (a) use of smartphone social network apps; and (b) watching a documentary. We assessed mechanical variables and ratings of perceived exertion during the strength exercise. Relative to the documentary-viewing control condition, a 30-minute exposure to smartphone social network apps led participants toward increased perception of mental fatigue (p = 0.004) and lower volume-load during the strength exercise (p = 0.006). There were no significant differences in perceived exertion between conditions (p = 0.54), participants' motivation (p = 0.277), intra-set mechanical variables (p > 0.05), or blood lactate concentrations (p = 0.36). Our findings of an isolated possible higher-than normal RPE without changes in physiological variables, accompanying the lower volume-load in the mentally-fatigued participants support psychological, rather than physiological, bases for mental fatigue effects.

Physiological Network From Anthropometric and Blood Test Biomarkers.

Currently, research in physiology focuses on molecular mechanisms underlying the functioning of living organisms. Reductionist strategies are used to decompose systems into their components and to measure changes of physiological variables between experimental conditions. However, how these isolated physiological variables translate into the emergence -and collapse- of biological functions of the organism as a whole is often a less tractable question. To generate a useful representation of physiology as a system, known and unknown interactions between heterogeneous physiological components must be taken into account. In this work we use a Complex Inference Networks approach to build physiological networks from biomarkers. We employ two unrelated databases to generate Spearman correlation matrices of 81 and 54 physiological variables, respectively, including endocrine, mechanic, biochemical, anthropometric, physiological, and cellular variables. From these correlation matrices we generated physiological networks by selecting a p-value threshold indicating statistically significant links. We compared the networks from both samples to show which features are robust and representative for physiology in health. We found that although network topology is sensitive to the p-value threshold, an optimal value may be defined by combining criteria of stability of topological features and network connectedness. Unsupervised community detection algorithms allowed to obtain functional clusters that correlate well with current medical knowledge. Finally, we describe the topology of the physiological networks, which lie between random and ordered structural features, and may reflect system robustness and adaptability. Modularity of physiological networks allows to explore functional clusters that are consistent even when considering different physiological variables. Altogether Complex Inference Networks from biomarkers provide an efficient implementation of a systems biology approach that is visually understandable and robust. We hypothesize that physiological networks allow to translate concepts such as homeostasis into quantifiable properties of biological systems useful for determination and quantification of health and disease.

Physiological, biochemical and transcriptional responses of Passiflora edulis Sims f. edulis under progressive drought stress

Water deficit stress is responsible for at least 40 % of crop losses worldwide, positioning itself as a strong threat to food security. Purple passion fruit (Passiflora edulis Sims f. edulis) is one of the most desirable exotic fruits on the world market mainly for its organoleptic properties. Information on the response to water deficit stress for purple passion fruit is scarce and in some cases contradictory. Therefore, the objective of the present work was to evaluate the morphological, physiological, biochemical and transcriptional response of purple passion fruit during water deficit and depict its strategy. The response of purple passion fruit plants to two water deficit treatments (T1: 50 % of irrigation, T2: 0% of irrigation compared to control) was evaluated during 40 days of stress, measuring changes in physiological variables related to growth and water relations, as well as the content of metabolites related to stress and the expression of genes associated with drought stress. Results show that the plant prevents water loss, by stomata closure, modulation of growth and accumulation of proline and sugars, while promoting root growth, features associated with tolerance to water deficit. At the expression level, early transcriptional activation of PeDREB2A and PeRD21A were detected in plants under the most severe stress, while PeGOLS1 and PeAFL1 upregulation were observed in plants under milder stress. These results suggest that purple passion fruit plants display an isohydric behavior and evade water deficit stress as a response strategy, where loss of water is avoided.