SAA Values Research Articles

Diagnostic and prognostic value of serum amiloid a in patients with idiopatic pulmonary fibrosis

Aims: the aim of our study was to investigate the diagnostic and prognostic value of SAA and its usability as a biomarker in patients with IPF. Methods: This study has been designed as a prospective, case-control study. Fifteen healthy individuals and 15 IPF patients. The demographic data and the measures from PFT, DLCO, laboratory tests of the patients included in the study were retrieved from IPF follow-up files. Results: The comparison of the IPF patient group with the group of healthy volunteers revealed significantly higher SAA values in IPF patients (p:0.005). A significant positive correlation was found between the patients' SAA and C-Reactive Protein (CRP) values. A negative significant correlation was found between the SAA values of the patients and the time to diagnosis (p<0.05). Despite the negative correlation between the SAA and FVC values of patients, no significant correlations were detected between these variables (p>0.05). This result suggests that SAA levels would be higher in newly or recently diagnosed . Conclusion: This study shows that SAA is significantly higher in IPF patients, suggesting that it will be a reliable biomarker feasible to predict the diagnosis. Future studies with larger patient groups ara needed.

Effect of Procaine Penicillin G and Flunixin Meglumine on Serum Amyloid A Response in Healthy Adult Horses.

This study was designed to determine the effect of PPG and/or flunixin meglumine on SAA response when used at clinical dosing regimens in healthy adult horses. Six healthy adult horses were enrolled in a crossover study design including one control and three treatment groups: no treatment (control); PPG alone (intramuscularly q12h for 72h); flunixin meglumine alone (intravenously q24h for 72h); and PPG (intramuscularly q12h for 72h) and flunixin meglumine (intravenously q24h for 72h). Whole blood was collected at 0, 24, 48, 72, 96 and 120 hours post-initial drug administration to measure SAA using a commercial lateral-flow immunoassay. The washout period was 30 days. Individual SAA values were within the reference range (≤ 20 µg/mL) for almost all horses in the control group. One control horse displayed a SAA value of 28 µg/mL at 72 hours. All horses from the PPG group showed normal SAA values throughout the study. Apart from one horse (SAA of 24 µg/mL at 96 hours) from the flunixin meglumine group, all horses showed normal SAA values. For the PPG and flunixin meglumine group, 5 horses had SAA values within reference range. One horse displayed increased SAA values (32-45 µg/mL) between 48 to 96 hours post-drug administration. There was no difference in area under the SAA time curve amongst control and treatment groups (P > 0.05). The administration of intramuscular PPG and/or intravenous flunixin meglumine does not trigger an inflammatory response that induces a SAA value above reference range in most adult healthy horses.

Evaluation of Oxidative Status, Cytokines, Acute Phase Proteins and Cardiac Damage Markers in Sheep Naturally Infected with Babesia ovis.

Babesiosis is a tick-borne disease caused by protozoon species in the Babesia genus of the Babesiadae family. The systemic inflammatory response induced by infection is considered to be an important feature of the pathophysiology of ovine babesiosis. In this study, it was aimed to determine serum oxidative status, levels of some cytokines, acute phase proteins and heart damage markers in babesiosis infection. A sample of 40 sheep was used for this purpose, of which 20 were healthy and 20 were infected with Babesia ovis. Babesia infection was diagnosed from Giemsa-stained peripheral blood smears. Infection was also confirmed by the polymerase chain reaction (PCR). Sera from blood samples was tested for oxidative stress parameters (malondialdehyde [MDA], total antioxidant status [TAS], superoxide dismutase [SOD], catalase [CAT] and glutathione peroxidase [GPx]), cytokines (interleukins IL-6, IL-1β, IL-10, tumour necrosis factor α (TNF-α) and interferon-ϒ [IFN-ϒ]), acute-phase proteins (C-reactive protein [CRP], serum amyloid A [SAA] and haptoglobin [Hp]) and specific (troponin I [cTnI], creatine kinase-MB [CK-MB]) and nonspecific (lactate dehydrogenase [LDH], aspartate transaminase [AST]) cardiac damage markers. MDA, SOD, CAT, Hp, TAS, IL-6, IL-10, TNF-α, IL-1β, INF-γ, AST, LDH, CK-MB mass and troponin I values were higher in the patient group than in the healthy group (P < 0.05). However, there was not found to be a statistical difference between the healthy and patient groups in terms of GPx, SAA and CRP values (P > 0.05). It can be stated that serum levels of oxidative stress, some acute phase proteins and cardiac damage markers may increase in naturally infected sheep with babesiosis.

Practical Application of a Urinary Zearalenone Monitoring System for Feed Hygiene Management of a Japanese Black Cattle Breeding Herd-Relevance to Anti-Müllerian Hormone and Serum Amyloid A Clarified from a Two-Year Survey.

In this study, a herd of Japanese Black (JB) breeding cattle with sporadic reproductive disorders was continuously monitored for an additional year to assess the effects of the urinary zearalenone (ZEN) concentration and changes in parameters (AMH and SAA) with time-lag variables and herd fertility (reproductive performance). This herd had high (exceeded the Japanese dietary feed regulations) urinary ZEN and rice straw ZEN concentrations (1.34 mg/kg). Long-term data of the herd with positive ZEN exposure revealed a decreasing ZEN concentration in urine and a gradual decrease in the AMH level with age. The AMH level was significantly affected by the ZEN value 2 months earlier and the AMH level in the previous month. The changes in ZEN and SAA values were significantly affected by the ZEN and SAA values in the previous month. Additionally, calving interval data between pre-monitoring and post-monitoring showed a significantly different pattern. Furthermore, the calving interval became significantly shorter between the time of contamination (2019) and the end of the monitoring period (2022). In conclusion, the urinary ZEN monitoring system may be a valuable practical tool for screening and detecting herd contamination in the field, and acute and/or chronic ZEN contamination in dietary feeds may affect herd productivity and the fertility of breeding cows.

Stress Reactivity After Pediatric Traumatic Brain Injury: Relation With Behavioral Adjustment.

Traumatic injury is linked increasingly to alterations in both stress response systems and psychological health. We investigated reactivity of salivary analytes of the hypothalamic-pituitary-adrenal axis (cortisol) and autonomic nervous system (salivary alpha amylase, sAA) during a psychosocial stress procedure in relation to psychological health outcomes. In a prospective cohort design, stress reactivity of children ages 8 to 15 years hospitalized for traumatic brain injury (TBI; n = 74) or extracranial injury (EI; n = 35) was compared with healthy controls (n = 51) 7 months after injury. Area under the curve increase (AUCinc) assessed pre-stressor to post-stressor cortisol and sAA values. Multi-variable general linear models evaluated demographic, family functioning, group, cortisol, and sAA AUCinc, and their interactions in relation to concurrent child and parent ratings of emotion regulation and internalizing and externalizing problems. Although AUCinc values were similar across groups, their relations with outcomes varied by group. Higher stress reactivity is typically associated with fewer adjustment problems. Relative to controls, greater sAA reactivity was associated with greater emotion dysregulation after TBI. In contrast, the relation of sAA reactivity with internalizing and generalized anxiety scores was flatter for both TBI and EI groups. The flattened and/or reversed direction of sAA reactivity with psychological health outcomes after TBI, and to a lesser degree EI, suggests autonomic nervous system dysregulation. Across groups, sAA reactivity interacted with sex on several psychological health outcomes with greater dysregulation in girls than in boys. Our findings highlight altered sAA, but not cortisol reactivity, as a potential mechanism of biological vulnerability associated with poorer adjustment after TBI.

EEG band power analysis corresponding to salivary amylase activity during stressful computer gameplay

The cortisol and norepinephrine from human salivary can represent psychological conditions. A portable salivary amylase monitor device (sAA) has existed; however, how the sAA corresponds to the central nervous system changes is still limited to carry out. Twenty university students aged between 20 and 22 years participated in which they played a stressful computer game during the experiment. Nineteen EEG electrodes were attached to the head scalp while the relative power on the delta, theta, alpha, and beta-band was calculated. The sAA value was obtained using a portable device called Nipro Cocorometer from Japan. The sAA levels and the brain's relative band power increased. Beta waves of the brain's right hemisphere were found higher than that of the left hemisphere, especially on the right temporal (T4, p &lt; 0.01). Then, we concluded that the beta-band power on the right hemisphere corresponds to wthe sAA changes.

A prospective study of serum amyloid A in relation to plasma administration in neonatal foals

SAA is a commonly used biomarker for measuring acute inflammation in equine practice, and the administration of prophylactic plasma to foals is a routine practice in large breeding farms. Despite this, limited information is available on the values of SAA in healthy or sick neonatal foals following this common procedure. A prospective study was conducted with 31 foals from a veterinary hospital in Texas in one year. Enrolled foals were part of a foaling program, where a prophylactic hyperimmunized plasma was administered 12 h after birth. Blood was collected for SAA measurements at birth and at 12 h (pre-plasma), 13 h (post-plasma), 24 h, 48 h, 72 h, and 96 h. Eight of the foals were clinically ill prior to plasma administration, and 23 foals were clinically normal. The mean SAA of all foals at birth was 1 μg/mL, increased to 11 μg/mL at 12 h (pre-plasma), and at 13 h (post-plasma) was 155 μg/mL. At 13 h, 65% of normal foals and 63% of sick foals had an SAA value >100 μg/mL. Transient but substantial increases in SAA following prophylactic plasma administration were frequently observed in this study. Veterinarians evaluating neonatal foals for clinical disease in the field should be cognizant of the timing of blood sampling in relation to plasma administration.

PENGEMBANGAN FORMULA BERBASIS BISKUIT PMT DAN UBI JALAR UNGU SEBAGAI ALTERNATIF MAKANAN TAMBAHAN UNTUK BALITA DENGAN BERAT BADAN TIDAK NAIK 2 KALI BERTURUT-TURUT (2T)

Background: The prevalence of malnutrition and severe malnutrition in Indonesia is still quite high. Modification of PMT for toddlers made from PMT biscuits and purple sweet potato was made to fulfill the nutritional needs of toddlers as supplementary food feeding. Purpose: Modified PMT for toddlers made from PMT biscuits and purple sweet potato for toddlers who don't gain weight 2 times in a row (2T). Methods: This type of research is an experimental study with a completely randomized design, consisting of 3 levels of treatment with a ratio of purple sweet potato: PMT biscuits, which is 60:40; 50:50 ; 40:60. The sampling technique used purposive sampling of as many as 15 panelists. Empirical calculations using the Table of Composition of Food Ingredients and the Ms. Ecel 2010. Excel 2010. It was held from January to March at the Mulyorejo Health Center. The variables studied were the content of energy, protein, fat, carbohydrates, iron, vitamin A, and organoleptic quality (color, aroma, taste, texture), SAA, MCT, and NPU values. Statistical analysis using the Kruskal Wallis test.Results: The PMT modified formula that had been made did not find a significant effect on the addition of purple sweet potato to the color (p=0.843), aroma (p=0.895), and texture (p=0.999) between treatments. There was a significant effect on the taste of the biscuit sweet potato balls (p=0.043). The value of energy, protein, fat, carbohydrates, iron was higher at P3 and vitamin A was higher at P1. The best treatment level was P3 with an energy density of 3.3 Kcal/gram (medium), SAA value of 107.9%, MCT 78.2%, and NPU value of 84.4%. Conclusion: Modification of PMT at the P3 treatment level (40% purple sweet potato and 60% PMT biscuits) can be used as an alternative supplementary food feeding for toddlers because it provides colors, aromas, tastes, and textures that are acceptable to toddlers.

0234 Salivary α-Amylase Response to Repeated Exposure to Acute Stressors Is Altered by Sleep Deprivation

Abstract Introduction Salivary α-amylase (sAA), a biomarker of autonomic nervous system (ANS) activity, is believed to reflect physiological responsiveness to stressors. Although exposure to stressors often co-occurs with sleep deprivation, little is known about their combined effects. We investigated the sAA response following repeated exposure to acute stressors at well-rested baseline and during total sleep deprivation (TSD). Methods As part of a larger study, N=8 healthy subjects (ages 29.0±6.6; 4 females) participated in a 4-day/3-night laboratory-based experiment. Subjects had 38h TSD preceded and followed by 10h sleep opportunities (22:00–08:00). On days 2 (baseline) and 3 (TSD), subjects completed two (A, B) deadly-force decision-making simulations in a high-fidelity shooting simulator with 30min rest between sessions. During each simulation, subjects (who were civilians) acted as police officers while viewing interactive videos depicting stressful law enforcement emergency response scenarios involving deadly-force decision-making. In these scenarios, subjects attempted to de-escalate the situations in the scenarios using verbal commands. If unsuccessful, they were to determine if the use of (simulated) deadly force was necessary and respond accordingly. Saliva samples were collected immediately before the first simulation of the baseline and TSD days, and immediately, 15min, and 30min after each simulation. Samples were assayed in duplicate using a sAA kinetic enzyme assay; results were normalized against the first pre-stressor sample of the baseline day. Results Post-simulation sAA values normalized to reference were analyzed with mixed-effects ANOVA with fixed effects of day and sample and their interaction and a random effect over subjects on the intercept. There was a significant effect of sample (F[5,76]=3.38, p=0.008) indicating that sAA spiked immediately after each deadly-force decision-making simulation. Planned comparisons revealed significantly blunted sAA during TSD compared to baseline immediately after the second simulation of the day (t[76]=2.09, p=0.040). Conclusion In our sample of civilian subjects, the deadly-force decision-making simulations elicited a sAA response, which was blunted after the second simulation on the day subjects were sleep-deprived, suggesting that TSD mediates the biological response to repeated exposure to acute stressors. Whether this result generalizes to police officers and military personnel trained in deadly-force decision-making remains to be determined. Support (If Any) ONR grant N00014-13-1-0302

Relationship of Troponin I with Neutrophil Lymphocyte Ratio and Serum Amyloid A in Acute Coronary Syndrome

Abstract&#x0D; Introduction: Acute coronary syndrome (ACS) is the leading cause of death in the world. Acute myocardial infarction can initiate an acute inflammatory process by inducing pro-inflammatory cytokines at the cellular level measured by NLR, at the biomolecular level characterized by SAA production in liver. The relationship of elevated troponin I levels as a marker of myocardial necrosis with NLR and SAA as inflammatory markers need further discussion. The purpose of this study was to determine the relationship between cardiac necrosis markers and inflammatory parameters in ACS.&#x0D; Methods: An analytic observational study with a cross-sectional approach was conducted from March to May 2019. This study involved 32 patients with ACS at the Emergency Department of Dr.Kariadi Hospital, with the onset of attacks of 4-6 hours which met the inclusion and exclusion criteria. Examination of troponin I level was done using the ELFA method, NLR value was measured using a hematology analyzer, and SAA level was measured using the ELISA method. Statistical test was done using Spearman correlation. Value of p &lt; 0.05 was considered significant.&#x0D; Results: The median (min-max) of troponin I, NLR, and SAA values were 0.617 (0.001-40,000) μg/L, 4.92 (1.38-18.16) and 40.454 (5.879-66.059) μg/ml, respectively. The correlation of troponin I level with NLR and SAA were r=0.180, p=0.243 and r=0.655, p=0.000.&#x0D; Conclusions: There was a significant positive moderate relationship between troponin I level and SAA which could be used as a marker of acute inflammation in ACS, whereas cell inflammation marker of NLR did not provide a significant meaning.&#x0D; Keywords: ACS, NLR, SAA, troponin

A Descriptive Study of the Clinical Presentation, Management, and Outcome of Horses with Acute Soft Tissue Trauma of the Tarsus and the Association with Synovial Involvement.

Simple SummaryThe hock is commonly involved in traumatic injuries in horses and due to the large number of synovial structures located in the region, this frequently results in synovial infection which is a major and potentially life-threatening complication in horses. The aim of this retrospective study was to describe the clinical presentation, diagnostic procedures, management, and outcome of cases with acute soft tissue trauma to the hock and to identify the clinical features that were associated with synovial infection in these cases. This study found that increased synovial effusion, severe lameness on admission, and the persistence of lameness as well as certain wound locations were more commonly associated with a diagnosis of synovial infection. Advanced diagnostic modalities such as radiographs, ultrasonography, and measurements of inflammatory markers aided in establishing the correct diagnosis. The duration of systemic antimicrobial treatment was shorter than previously reported and many cases received local antimicrobial treatment at the site of injury, which may have improved its efficacy. At the time of discharge, while lameness was still present in some cases, the overall survival was excellent. This study describes the clinical features and treatment of these commonly encountered injuries, and this knowledge may benefit clinicians in the future.The tarsus is one of the most common areas of traumatic injury with associated synovial involvement (SI) in horses. The aim of this retrospective study was to describe the clinical presentation, diagnostic procedures, management (emphasizing the type, duration, and route of antimicrobial administration), and outcome of cases with acute soft tissue trauma to the tarsal region. The presenting clinical features, the results of diagnostic modalities, and the initial response to therapy were assessed for their usefulness to predict SI. Medical records of 72 cases were included and SI was diagnosed in 34 cases (47.2%). Increased synovial effusion, lameness on admission (OR = 4.1; 95%CI 1.0–16.4), persistent lameness (OR = 5.7; 95%CI 1.8–17.9), increased blood SAA values (≥200 mg/L) from initial to second measurement (OR = 4.3; 95%CI 1.2–15.5), and wound location on the plantar/plantarolateral/plantaromedial compared to the lateral aspect of the tarsus (OR = 7.0; 95%CI 1.6–30.9) were associated with SI. Radiographs, ultrasonography, and the use of pressure testing when a wound was present proved to be useful in correctly diagnosing SI. The median duration of systemic antimicrobial administration was 8 (IQR: 5 to 9) days and most horses received local antimicrobial therapy. This study highlights several relevant clinical features and their association with SI and emphasizes the usefulness of local antimicrobial therapy in these cases.

ANALYZING THE INFLUENCING FACTORS OF SPORTS FATIGUE BASED ON ALGORITHM

ABSTRACT Objective: This paper discusses the monitoring method of exercise fatigue and analyzes the influencing factors of exercise fatigue. Methods: Based on the feature extraction method of the fatigue image signal, a series of changes caused by exercise fatigue are analyzed by the biofeedback technique. SVM algorithm and neural network model are used to identify the fatigue state of motion. Characteristics of electroencephalogram (EEG) and electromyography (EMG) during fatigue. Results: When sports fatigue occurred, the composite index of bio-feedback technology shows a decrease in HRV index and increases in HRV time-domain indicators, frequency-domain indicators, and SAa values. Conclusions: It has a high degree of systematization. The proposed method is non-invasive and has practical application value. Level of evidence II; Therapeutic studies - investigation of treatment results.

Investigation of The Usefulness of Serum Amyloid A in Characterizing Selected Disease Forms of Equine Herpesvirus-1 Infection

The objective of this study was to study the SAA response of horses with various forms of EHV-1 infection. Archived serum samples from 153 horses with various disease forms of EHV-1 infection (48 healthy non-infected horses, 48 subclinically infected horses, 40 horses with respiratory EHV-1 infection and 17 horses with neurological EHV-1 infection) were available for SAA testing. SAA values ranged from 0 to 31 µg/mL (median 0 µg/mL) in healthy horses, from 0 to 2,416 µg/mL (median 8.5 µg/mL) in subclinically infected horses, from 0 to 3,000 µg/mL (median 597 µg/mL) in horse with respiratory EHV-1 infection and from 0 to 1,640 µg/mL (median 58 µg/mL) in horse with neurological EHV-1 disease. Infected horses had significantly higher SAA values compared to healthy, non-infected horses. While SAA was elevated in the majority of horses with evidence of EHV-1 infection, a single point in time SAA test was unable to consistently support infection in horses with subclinical disease

Comparative evaluation of cytokine and acute-phase protein concentrations in sera of dairy cows with subclinical and clinical ketosis as a different view of the causes of the disease.

Background and Aim:Ketosis is a common disease occurring during the first stage of lactation in highly productive dairy cows. The aim of the present study was the comparative assessment of selected pro-inflammatory cytokines (including tumor necrosis factor-α [TNF-α] and interleukin 6 [IL-6]), anti-inflammatory cytokines (including IL-10), and acute-phase proteins (APPs) (including haptoglobin [Hp] and serum amyloid A [SAA]), in the sera of cows with subclinical ketosis (SCK), in those with clinical ketosis (CK), and in healthy cows.Materials and Methods:Thirty dairy cows of Holstein-Friesian breed were investigated. The cows were divided into three groups depending on the serum β-hydroxybutyric acid (βHBA) level. The control, SCK, and CK groups included healthy cows, cows with SCK, and cows with CK, respectively. BHBA concentration in blood serum was determined using colorimetric method. The blood serum was used for proper tests. Cytokine (TNF-α, IL-6, and IL-10) and APPs (SAA and Hp) concentrations in the investigated samples were determined by enzyme-linked immunosorbent assay method.Results:The SCK group had significantly higher TNF-α, IL-6; IL-10, and SAA values than had the CK group (p<0.01). The SCK group had a lower Hp concentration than had the CK group (p<0.05).Conclusion:This study showed that the inflammation intensity is higher in the initial phase of the disease and decreases during the advancement, probably due to active anti-inflammatory mechanisms (an increase of IL-10 concentration), which protect animal organism from self-destruction. On the basis of our study, it can be assumed that ketosis development in dairy cows was preceded by the systemic inflammation that may influence the progress of this disease.

Evaluation of salivary stress biomarker changes after the insertion of complete dentures

Introduction/Objective. The purpose of this study was to assess the relationships between salivary stress markers [salivary ?-amylase (sAA) and pH], and patients? stress with new dentures. Methods. An intra-individual evaluation was done, in which 30 participants older than 65 years, both sexes, in good general health, first-time complete dentures (CDs) wearers, took part. Measuring of stress biomarkers was done in the unstimulated saliva collected by the so-called spitting method: (1) before any prosthetic treatment, (2) after insertion of a new pair of CDs, and (3) two months after CDs delivery. Results. Upon evaluating the obtained data it was observed that the sAA values steadily increased and by the end of the observation period sAA was higher in women but without statistical significance. The pH values increased until the second follow-up period, after which they dropped. The post-hoc test showed a statistically significant difference in pH values between the first vs. the second (p = 0.005) and the second vs. the third (p = 0.001) follow-up periods. Conclusion. There was a non-significant increase in sAA values during the adaptation period. The biggest difference in sAA values between men and women was at the moment of insertion of dentures. The highest pH level was after the insertion of dentures. Since sAA changes were of no statistical significance, the sAA and pH values cannot be used as a reliable biomarker in saliva for observing the patients? adaptation, psychological, and emotional issues.

Efficiency of methionine and cystine utilization by broiler chickens using stable isotopes

The aim of this study was to develop a method to determine the efficiency of utilization of Met and Cys using stable isotopes in order to reduce the number of sacrificed animals relative to the comparative slaughter technique. Met and Cys efficiencies were obtained separately and as total SAA values. Twenty-one 14- to 28-day-old broiler chickens were fed experimental diets containing different Met:Cys ratios (44:56, 50:50 and 56:44). Birds were given diets with daily supplements of L-(15 N) Met (60mmol/kg) or L-(15 N2 ) Cys (35mmol/kg) throughout the entire experimental period. Excreta were collected daily, and birds were euthanized at the end of the trial to collect feather-free bodies and feathers. Samples were analysed for 15 N and 15 N-Met content. The utilization efficiency for Met, Cys and Met+Cys for feather-free bodies was 55%, 75%, and 60%, while the efficiencies for feathers were estimated at 96%, 77% and 84% respectively.

Bedtime doses of prazosin do not affect daytime salivary amylase markers in PTSD

Overactivity of the noradrenergic (NE) system within the central nervous system (CNS) has been postulated as a key pathophysiology of posttraumatic stress disorder (PTSD). The activity of the enzyme salivary α-amylase (sAA) has been proposed as an indirect measure of CNS NE activity, and sAA is elevated in PTSD. As an antagonist of the α-1 NE receptor, prazosin would be expected to alter sAA values in PTSD patients. However, given its short half-life, it is not clear whether bedtime doses would have an effect on daytime sAA. In the present study, we assayed daytime sAA in 20 suicidal PTSD patients who were randomized to prazosin versus placebo at bedtime-only, and found no effect in daytime sAA. These findings are consistent with studies showing an advantage for twice daily dosing of prazosin in PTSD.

Intensive longitudinal modelling predicts diurnal activity of salivary alpha-amylase.

Salivary alpha-amylase (sAA) activity has been widely used in psychological and medical research as a surrogate marker of sympathetic nervous system activation, though its utility remains controversial. The aim of this work was to compare alternative intensive longitudinal models of sAA data: (a) a traditional model, where sAA is a function of hour (hr) and hr squared (sAAj,t = f(hr, hr2), and (b) an autoregressive model, where values of sAA are a function of previous values (sAAj,t = f(sAA j,t-1, sAA j,t-2, …, sAA j,t-p). Nineteen normal subjects (9 males and 10 females) participated in the experiments and measurements were performed every hr between 9:00 and 21:00 hr. Thus, a total of 13 measurements were obtained per participant. The Napierian logarithm of the enzymatic activity of sAA was analysed. Data showed that a second-order autoregressive (AR(2)) model was more parsimonious and fitted better than the traditional multilevel quadratic model. Therefore, sAA follows a process whereby, to forecast its value at any given time, sAA values one and two hr prior to that time (sAA j,t = f(SAAj,t-1, SAAj,t-2) are most predictive, thus indicating that sAA has its own inertia, with a “memory” of the two previous hr. These novel findings highlight the relevance of intensive longitudinal models in physiological data analysis and have considerable implications for physiological and biobehavioural research involving sAA measurements and other stress-related biomarkers.

Stress Profile in Remotely Piloted Aircraft Crewmembers During 2 h Operating Mission.

Emotional stability plays a key role in individual and team performance during both routine activities and management of unexpected emergencies. Using a psycho-physiological approach, the stress response was investigated in drone operators in service.Methods: Salivary α-amylase (sAA), galvanic skin response (GSR) and anxiety were assessed over a 2-h operating flight.Results: Compared to baseline values, GSR and sAA values increased in operating conditions. Moreover, these values were higher in Pilots than in Sensor Operators, indicating that their stress response was greater. These results were associated with an increase in anxiety level, highlighting a relationship between autonomic reactivity and anxiety.Conclusion: This is the first report providing experimental evidences of the stress response related to Remotely Piloted Aircraft operations.

Influence of the way of reporting alpha-Amylase values in saliva in different naturalistic situations: A pilot study.

The objective of this pilot study was to compare the different ways of measuring salivary alpha-amylase (sAA, enzymatic vs. concentration) and to evaluate the influence that the different ways of reporting the results can have in sAA interpretation. For this purpose, sAA was measured by direct quantification and also by an enzymatic assay in three different naturalistic situations, a physical stressor (situation 1) and two mental stressors of different intensity (situations 2 and 3). The results were expressed in three different ways (without correction, multiplied by flow rate and divided by protein concentration). sAA concentration and activity increased just after situations 1 and 3. When values were multiplied by the flow rate, significant changes after situation 1 were detected only for sAA activity but not for sAA concentration, being these changes of lower significance and magnitude that those observed for sAA activity without any correction. In addition, a significant increase in sAA activity was found at T+15 in situation 2. In situation 3 the significant decrease in sAA at T+15 disappeared. When values were divided by protein concentration, there were no significant changes in situations 1 or 3, but a decrease in situation 2 at T+0 and an increase at T+15. sAA activity and concentration showed a significant correlation in all situations. This pilot study points out that the way of expressing sAA can influence the results obtained in different stress models and also their interpretation. Therefore, how sAA is reported and the factors involved in the different ways of expressing sAA, should be taken into consideration for an objective interpretation of sAA values.