Oral Body Temperature Research Articles

Repeated Sprint Variations According to Circadian Rhythm at Different Menstrual Cycle Phases.

This study assessed the repeated sprint performance in relation to circadian rhythm during different menstrual cycle phases (MCP). Twelve volunteer eumenorrheic women team sport athletes performed 5×6-s cycling sprints in morning (9 am to 10 am) and evening (6 pm to 7 pm) sessions during the mid-follicular (FP, 6th-10th d) and luteal phases (LP, 19th-24th d). Body weight, oral body temperature, resting heart rate and lactate levels together with estradiol, progesterone and cortisol levels were determined before tests. Relative peak and mean power and performance decrements were determined as performance variables and maximum heart rate, lactate and ratings of perceived exertion were determined as physiological variables. Evening body temperatures were significantly higher. Cortisol levels were higher in the morning and in the FP. Resting lactate levels did not vary with MCP or time of day, but a significant MCP x time of day interaction was observed. Body weight showed no change according to time of day and MCP. There was no significant effect of MCP and time of day on performance and physiological variables, in contrast, maximum lactate values were notably higher in the evening. In conclusion, MCP and time of day need not be considered during repeated sprint exercises of eumenorrheic women athletes.

Novel Methodology for Identifying the Occurrence of Ovulation by Estimating Core Body Temperature During Sleeping: Validity and Effectiveness Study.

Body temperature is the most-used noninvasive biomarker to determine menstrual cycle and ovulation. However, issues related to its low accuracy are still under discussion. This study aimed to improve the accuracy of identifying the presence or absence of ovulation within a menstrual cycle. We investigated whether core body temperature (CBT) estimation can improve the accuracy of temperature biphasic shift discrimination in the menstrual cycle. The study consisted of 2 parts: experiment 1 assessed the validity of the CBT estimation method, while experiment 2 focused on the effectiveness of the method in discriminating biphasic temperature shifts. In experiment 1, healthy women aged between 18 and 40 years had their true CBT measured using an ingestible thermometer and their CBT estimated from skin temperature and ambient temperature measured during sleep in both the follicular and luteal phases of their menstrual cycles. This study analyzed the differences between these 2 measurements, the variations in temperature between the 2 phases, and the repeated measures correlation between the true and estimated CBT. Experiment 2 followed a similar methodology, but focused on evaluating the diagnostic accuracy of these 2 temperature measurement approaches (estimated CBT and traditional oral basal body temperature [BBT]) for identifying ovulatory cycles. This was performed using urine luteinizing hormone (LH) as the reference standard. Menstrual cycles were categorized based on the results of the LH tests, and a temperature shift was identified using a specific criterion called the "three-over-six rule." This rule and the nested design of the study facilitated the assessment of diagnostic measures, such as sensitivity and specificity. The main findings showed that CBT estimated from skin temperature and ambient temperature during sleep was consistently lower than directly measured CBT in both the follicular and luteal phases of the menstrual cycle. Despite this, the pattern of temperature variation between these phases was comparable for both the estimated and true CBT measurements, suggesting that the estimated CBT accurately reflected the cyclical variations in the true CBT. Significantly, the CBT estimation method showed higher sensitivity and specificity for detecting the occurrence of ovulation than traditional oral BBT measurements, highlighting its potential as an effective tool for reproductive health monitoring. The current method for estimating the CBT provides a practical and noninvasive method for monitoring CBT, which is essential for identifying biphasic shifts in the BBT throughout the menstrual cycle. This study demonstrated that the estimated CBT derived from skin temperature and ambient temperature during sleep accurately captures variations in true CBT and is more accurate in determining the presence or absence of ovulation than traditional oral BBT measurements. This method holds promise for improving reproductive health monitoring and understanding of menstrual cycle dynamics.

Comparing body temperature measurements using the double sensor method within a wearable device with oral and core body temperature measurements using medical grade thermometers-a short report.

Introduction: Body temperature is essential for diagnosing, managing, and following multiple medical conditions. There are several methods and devices to measure body temperature, but most do not allow continuous and prolonged measurement of body temperature. Noninvasive skin temperature sensor combined with a heat flux sensor, also known as the "double sensor" technique, is becoming a valuable and simple method for frequently monitoring body temperature. Methods: Body temperature measurements using the "double sensor" method in a wearable monitoring device were compared with oral and core body temperature measurements using medical grade thermometers, analyzing data from two prospective clinical trials of different clinical scenarios. One study included 45 hospitalized COVID-19 patients in which oral measurements were taken using a hand-held device, and the second included 18 post-cardiac surgery patients in which rectal measurements were taken using a rectal probe. Results: In study 1, Bland-Altman analysis showed a bias of -0.04°C [0.34-(-0.43)°C, 95% LOA] with a correlation of 99.4% (p < 0.001). In study 2, Bland-Altman analysis showed a bias of 0.0°C [0.27-(-0.28)°C, 95% LOA], and the correlation was 99.3% (p < 0.001). In both studies, stratifying patients based on BMI and skin tone showed high accordance in all sub-groups. Discussion: The wearable monitor showed high correlation with oral and core body temperature measurements in different clinical scenarios.

Menstrual Cycle Related Fluctuations in Circulating Markers of Bone Metabolism at Rest and in Response to Running in Eumenorrheic Females

This study examined potential fluctuations in bone metabolic markers across the menstrual cycle both at rest and after a 30-min bout of continuous running at 80% of V̇O2max. Resting and post-exercise (0, 30, 90min) sclerostin, parathyroid hormone (PTH), carboxy-terminal cross-linking telopeptide of type I collagen (β-CTXI), and procollagen type 1N propeptide (PINP) were assessed in 10 eumenorrheic women (age: 21 ± 3 y, BMI: 23.2 ± 3.0kg.m2) during the mid- to late-follicular (FP: day 8.0 ± 1.4) and mid-luteal (LP: day 22.0 ± 2.5) phases of the menstrual cycle. Ovulation was determined using ovulation kits and daily measurement of oral body temperature upon awakening. Menstrual cycle phase was subsequently confirmed by measurement of plasma estradiol and progesterone. On average, resting estradiol concentrations increased from 46.3 ± 8.9pg·mL-1 in the FP to 67.3 ± 23.4pg·mL-1 in the LP (p = 0.015), and resting progesterone increased from 4.12 ± 2.36ng·mL-1 in the FP to 11.86 ± 4.49ng·mL-1 in the LP (p < 0.001). At rest, there were no differences between menstrual cycle phases in sclerostin (FP: 260.1 ± 135.0pg·mL-1; LP: 303.5 ± 99.9pg·mL-1; p = 0.765), PTH (FP: 0.96 ± 0.64pmol·L-1; LP: 0.79 ± 0.44pmol·L-1; p = 0.568), β-CTXI (FP: 243.1 ± 158.0ng·L-1; LP: 202.4 ± 92.3ng·L-1; p = 0.198), and PINP (FP: 53.6 ± 8.9μg·L-1; LP: 66.2 ± 20.2μg·L-1; p = 0.093). Main effects for time (p < 0.05) were shown in sclerostin, PTH, β-CTXI and PINP, without phase or interaction effects. Sclerostin increased from pre- to immediately post-exercise (45%; p = 0.007), and so did PTH (43%; p = 0.011), both returning to resting concentrations 30min post-exercise. β-CTXI decreased from pre- to post-exercise (20%; p = 0.027) and was stillbelow its pre-exercise concentrations at 90min post-exercise (17%; p = 0.013). PINP increased immediately post-exercise (29%; p < 0.001), returning to resting concentrations at 30min post-exercise. These results demonstrate no effect of menstrual cycle phase on resting bone marker concentrations or on the bone metabolic marker response to intense exercise.

Physiological and biochemical parameters among a population of bakers exposed to environmental heat.

The aim of this study was to determine the physiological and biochemical changes among bakers, induced by heat exposure at the workplace. Information was collected by means of a self-administered questionnaire. Vital signs were measured and recorded by a trained nurse before and after each work shift. A venous blood sample was drawn at the end of each work shift. The mean wet-bulb globe temperature (WBGT) index in the bakeries and offices was measured. This was a cross-sectional study involving 137 bakers working in 20 bakeries, and 107 control subjects comparable in terms of age, race, marital status, years of service, income, and cigarette smoking. There was a significant weight loss and increase in the respiratory rate, the heart rate, and oral body temperature among the bakers compared to the control group. Sodium levels were significantly lower, while blood urea nitrogen levels were significantly higher, among the bakers than in the control group. There were unfavorably hot working conditions in the bakeries: the WBGT index in the bakeries was 37.4°C while the average WBGT for the offices was 25.5°C. The changes in the physiological and biochemical parameters among the bakers were found to be associated with exposure to high environmental heat in the bakeries, as judged by the WBGT index. Preventive measures should be aimed at reducing the adverse effects of heat exposure among bakers and should be directed towards the man-machine-environment triad. Int J Occup Med Environ Health. 2022;35(3):265-72.

The optimal oral body temperature cutoff and other factors predictive of sepsis diagnosis in elderly patients.

INTRODUCTION:The aim of this study was to identify the optimal oral temperature cut-off value and other factors predictive of sepsis in elderly patients presenting to emergency department.METHODS:A hospital-based retrospective study was performed on all elderly patients who presented to the Adult Emergency Department at King Abdulaziz Medical City in Riyadh (January to December 31, 2018).RESULTS:Of total of 13,856 patients, 2170 (15.7%) were diagnosed with sepsis. The associated area under the curve estimate was 0.73, 95% confidence interval (CI) 0.72–0.74. Body temperature ≥37.3 was found as optimal cut-point with sensitivity = 50.97% and specificity = 87.22% and 82.39% of patients with sepsis will be correctly classified using this cut-off. An increase of 1° in body temperature was associated with an odds ratio of 9.95 (95% CI 8.95–11.06, P < 0.0001). Those aged ≥100 years having 11.12 (95% CI 2.29–20.88, P < 0.0001) times the likelihood for sepsis diagnosis compared with those aged 60–69 years. People admitted in weather such as winter, spring, or autumn were more likely to develop sepsis than people admitted in summer.CONCLUSION:The risk factors of sepsis such as age, temperature, and seasonal variation inform important evidence-based decisions. The hospitals dealing with sepsis patients should assess older patients for other severe illnesses or co-morbid that might lead to sepsis if left untreated. Therefore, older patients need to be prioritized over younger patients. The body temperature of patients admitted to hospitals needs to be monitored critically and it is important to consider seasonal fluctuations while managing cases of sepsis and allocating resources. Our findings suggest that clinicians should explore the possibility of sepsis in elderly patients admitted to emergency units with oral temperature ≥37.3°C. Risk factors for sepsis reported in this study could inform evidence-based decisions.

Intravenous Versus Oral Acetaminophen Use in Febrile Neurocritical Care Patients.

The use of intravenous (IV) acetaminophen (APAP) for fever has not been thoroughly studied in neurocritical care (NCC) patients, in whom a temperature of ≥38°C is associated with poor outcomes and treatment to normothermia is common practice. This retrospective study evaluated NCC patients admitted between May 1, 2012, and April 30, 2013, and received at least one dose of IV or oral (PO) APAP for a body temperature of ≥38°C. The primary aim of this study was to compare the reduction in body temperature (RIT) between IV and PO APAP, calculated as the change in temperature before and 0.5, 1, 2, 3, and 6 hours after administration. Descriptive statistics were used to assess use characteristics, and Kruskal-Wallis and Mann-Whitney U tests were used for between-group differences. There were 142 NCC patients who received a total of 405 IV APAP and 253 PO APAP doses. Seventy percent of all APAP doses resulted in a temperature of <38°C within 6 hours. The median oral body temperature before APAP was 38.8°C and 38.6°C for IV and PO APAP, respectively (p < 0.01). The median RIT at 0.5 (IV 0.25°C vs. PO 0.2°C), 1 (IV 0.4°C vs. PO 0.2°C), 2 (IV 0.7°C vs. PO 0.5°C), 3 (IV 0.9°C vs. PO 0.6°C), and 6 (IV 1°C vs. PO 0.8°C) hours was significantly greater for IV APAP than for PO APAP at all time points (p < 0.05). Patients with an acute ischemic stroke and patients with an intracerebral hemorrhage had a statistically significantly greater RIT with IV APAP therapy. IV APAP administered to febrile NCC patients was associated with a significantly greater RIT than PO, but 70% of all APAP doses resulted in a body temperature of <38°C within 6 hours. Further prospective studies are needed to determine if IV APAP improves clinical outcomes.

Case Studies Of Yoga For Stress Reduction During Covid-19 "shelter In Place" Conditions

PURPOSE: To investigate the effect of yoga and physical exercise on cortisol levels and blood pressure during periods of stress caused by COVID19 "shelter in place" orders. METHODS: Subjects were two older adults (male and female, mean age 64). No other subjects were included due to Georgia State’s "shelter-in-place" conditions in the USA, during the IRB approved study. Activity diaries were maintained listing, 1) trips made to necessary stores between 9 and 11 am, and 2) activities performed between 11 am and 12 noon (designated as either yoga or aerobic exercise or sedentary desk work). Subjects 1) filled saliva sample tubes according to manufacturer directions (ZRT Laboratory) for cortisol determination, 2) measured oral body temperature and 3) measured wrist blood pressure (BP) with an Omron HEM-605 digital monitor at 7 am and 12 noon. Yoga sessions lasted 20 minutes (Pullen, 2009). Aerobic exercise consisted of a 20 minute brisk walk on a motorized treadmill and/or elliptical machine, at moderate intensity, as described by ACSM Guidelines for Exercise Testing and Prescription (2000). Participants answered the Perceived Stress Scale and Pandemic Stress Index instruments at study conclusion. Sentiment analysis scores of broadcast news were extracted from the New York Times to assess stress from daily reports. RESULTS: Study was conducted from April 4 -24, 2020 under "shelter in place" orders. Participants both scored low stress from the stress instruments, while the news sentiment varied, with definite negative scores. While trends in diastolic BP, heart rate and cortisol levels were inconsistent between the interventions of physical activity or yoga compared to sedentary activity, a definite trend was seen between systolic BP and the news sentiment daily measure. As the daily news sentiment score changed from -0.42 to -0.47, SBP increased from -10 to +35 mmHg change between mornings to afternoon. Correlation coefficient was 0.19 for N = 11. CONCLUSIONS: The lack of correlation in diastolic BP, heart rate and cortisol levels with intervention was probably due to small participant numbers and short study span. The correlation of systolic BP with news sentiment analysis was surprising, and indicated such measures should be included in human subject’s research concerning stress measures as a possible confounder.

Potential Role of Amino Acids in the Adaptation of Chicks and Market-Age Broilers to Heat Stress.

Increased average air temperatures and more frequent and prolonged periods of high ambient temperature (HT) associated with global warming will increasingly affect worldwide poultry production. It is thus important to understand how HT impacts poultry physiology and to identify novel approaches to facilitate improved adaptation and thereby maximize poultry growth, health and welfare. Amino acids play a role in many physiological functions, including stress responses, and their relative demand and metabolism are altered tissue-specifically during exposure to HT. For instance, HT decreases plasma citrulline (Cit) in chicks and leucine (Leu) in the embryonic brain and liver. The physiological significance of these changes in amino acids may involve protection of the body from heat stress. Thus, numerous studies have focused on evaluating the effects of dietary administration of amino acids. It was found that oral l-Cit lowered body temperature and increased thermotolerance in layer chicks. When l-Leu was injected into fertile broiler eggs to examine the cause of reduction of Leu in embryos exposed to HT, in ovo feeding of l-Leu improved thermotolerance in broiler chicks. In ovo injection of l-Leu was also found to inhibit weight loss in market-age broilers exposed to chronic HT, giving rise to the possibility of developing a novel biotechnology aimed at minimizing the economic losses to poultry producers during summer heat stress. These findings and the significance of amino acid metabolism in chicks and market-age broilers under HT are summarized and discussed in this review.

İyi Antrenmanlı Yarı-profesyonel Futbolcuların Koşuya Dayalı Anaerobik Sprint Test Performansında Diurnal Varyasyonlar

Objective: This study examined whether there were diurnal variations in the running-based anaerobic sprint test (RAST) performance of semi-professional, male soccer players. Material and Methods: Participants included 25 people whose ages ranged from 18- 36 years old, (mean=20 years); weight ranged from 52-110 kg (mean=72 kg); mean height was 176.92±6.17 cm; experience playing soccer ranged from 5-22 years (mean=8 years); and average weekly training duration was 3-22 h (mean=6 h). Chronotypes were estimated using the Turkish version of the Horn-Östberg Morningness-Eveningness Personality Questionnaire. They performed RAST in a randomized study design using the Newtest Powertimer 300-series photocells twice, on two separate days, one week apart, either in the morning (8.30-10.00 AM) or afternoon (5.00-6.00 PM). Before each of test session; the air temperature and humidity; along with their oral body temperature and 24 h food intake data were recorded. Resultsː Paired t-tests were used to analyze differences due to the time of day in the RAST variables. Maximum power (p>0.05), minimum power (p>0.05), mean power (p>0.05), fatigue index (p>0.05), air temperature (p>0.05), body temperature, and caloric intake (p>0.05) did not differ in the morning and afternoon. Conclusion: In contrast to previous research, RAST performance showed no diurnal variations. A possible explanation could be attributed to the participants' chronotypes conforming to neither the morning nor evening types. However, replicating this study with soccer players having an extreme morning or extreme evening chronotypes may lead to different results.

The Effect of the Menstrual Cycle on Daily Measures of Heart Rate Variability in Athletic Women

Abstract. Heart rate variability (HRV) is a biomarker used to reflect both healthy and pathological state(s). The effect of the menstrual cycle and menstrual cycle phases (follicular, luteal) on HRV remains unclear. Active eumenorrheic women free from exogenous hormones completed five consecutive weeks of daily, oral basal body temperature (BBT) and HRV measurements upon waking. Descriptive statistics were used to characterize shifts in the HRV measures: standard deviation of NN intervals (SDNN), root mean square of successive difference (rMSSD), high (HF) and low frequency (LF) across the menstrual cycle and between phases. All HRV measures were assessed by medians ( Mdn), median difference of consecutive days ( Mdn∆) and variance. Seven participants ( M ± SD; age: 28.60 ± 8.40 year) completed the study with regular menstrual cycles (28.40 ± 2.30 days; ovulation day 14.57 ± 0.98 day). Median rMSSD displayed a nonlinear decrease across the menstrual cycle and plateau around the day of ovulation. A negative shift before ovulation in Mdn∆, rMSSD, SDNN, and LF as well as peak on luteal phase Day 4 in rMSSD and SDNN was observed. Median variance increased in rMSSD (150.06 ms2) SDNN (271.12 ms2), and LF variance (0.001 sec2/Hz) from follicular to luteal phase. Daily HRV associated with the parasympathetic nervous system was observed to decrease nonlinearly across the menstrual cycle.

Abnormalities of Vital Signs in Children with Cerebral Palsy: Relationship to Physical Disabilities

The autonomic functions of children with cerebral palsy (CP) have not been sufficiently explored, and corresponding abnormalities are underdiagnosed. In addition, studies evaluating the associations between autonomic dysfunctions and the different aspects of motor performance among these children are scarce. We aimed to investigate vital signs in children with CP and compare them to those of children with typical motor development (TMD) and to determine the associations of autonomic dysfunction with the demographic and clinical data and motor characteristics of these children. A convenience sample of 118 children with CP was evaluated in this cross-sectional study. A group of 69 matched children with TMD served as a control group. We measured the vital signs and key pinch and hand grip strengths of all children in the study. Vital signs were recorded while the children rested in a comfortable sitting position. Children with CP were evaluated for muscle tone and motor abilities. Systolic BP, diastolic BP, heart rate, and respiratory rate were significantly higher in children with CP than in children with TMD (p values of 0.03, 0.006, 0.02, and 0.001, respectively), while blood oxygen saturation and oral body temperature were significantly lower (p values of 0.00 and 0.003, respectively). We detected only weak to moderate correlations between some vital sign abnormalities and children with lower motor performance (diplegic and quadriplegic children, children with level IV or V on the gross motor function classification system (GMFCS), and children with low key pinch and hand grip strength). Children with CP had abnormalities in their vital signs at rest, reflecting a state of dysautonomia. Abnormalities included high systolic BP, diastolic BP, heart rate, and respiratory rate and low blood oxygen saturation and oral body temperature. Children with lower motor performance were at a greater risk of dysautonomia.

Development and characterization of an effective food allergy model in Brown Norway rats.

BackgroundFood allergy (FA) is an adverse health effect produced by the exposure to a given food. Currently, there is no optimal animal model of FA for the screening of immunotherapies or for testing the allergenicity of new foods.ObjectiveThe aim of the present study was to develop an effective and rapid model of FA in Brown Norway rats. In order to establish biomarkers of FA in rat, we compared the immune response and the anaphylactic shock obtained in this model with those achieved with only intraperitoneal immunization.MethodsRats received an intraperitoneal injection of ovalbumin (OVA) with alum and toxin from Bordetella pertussis, and 14 days later, OVA by oral route daily for three weeks (FA group). A group of rats receiving only the i.p. injection (IP group) were also tested. Serum anti-OVA IgE, IgG1, IgG2a, IgG2b and IgA antibodies were quantified throughout the study. After an oral challenge, body temperature, intestinal permeability, motor activity, and mast cell protease II (RMCP-II) levels were determined. At the end of the study, anti-OVA intestinal IgA, spleen cytokine production, lymphocyte composition of Peyer’s patches and mesenteric lymph nodes, and gene expression in the small intestine were quantified.ResultsSerum OVA-specific IgG1, IgG2a and IgG2b concentrations rose with the i.p. immunization but were highly augmented after the oral OVA administration. Anti-OVA IgE increased twofold during the first week of oral OVA gavage. The anaphylaxis in both IP and FA groups decreased body temperature and motor activity, whereas intestinal permeability increased. Interestingly, the FA group showed a much higher RMCP II serum protein and intestinal mRNA expression.ConclusionsThese results show both an effective and relatively rapid model of FA assessed by means of specific antibody titres and the high production of RMCP-II and its intestinal gene expression.

Measures of circadian preference in childhood and adolescence: A review

PurposeTo review the psychometric properties of the questionnaires commonly filled in by children and adolescents to measure circadian preference. MethodsWe examined the Morningness-Eveningness Questionnaire for Children and Adolescents (MEQ-CA), the Morningness-Eveningness Scale for Children (MESC) and the Composite Scale of Morningness (CSM). We critically analyzed the reliability, in term of internal consistency (through the Cronbach's alpha) and test-retest reliability (through the correlation coefficient), and the type of validation against external criteria (objective assessment of the sleep/wake cycle, body temperature, hormones and other questionnaires). Fifty studies that reported these data were included in the review: 7 studies used the MEQ-CA, 28 used the MESC and 15 used the CSM. ResultsThe percentage of studies reporting at least acceptable levels of internal consistency was high and similar between the three questionnaires. Evidence for test-retest reliability was scant, since only 3 studies were available; it was at least acceptable for the MESC (two studies with a time interval of 1 month), not acceptable for the MEQ-CA (one study with a time interval of 6 months), while no information was available for the CSM. As regards the validation evidence, the MEQ-CA has been validated by the highest number of external criteria (actigraphy, oral body temperature and other questionnaires), followed by the CSM (cortisol sampling and other questionnaires). The MESC has been validated only against self-report measures. ConclusionsThe present state of the art would suggest the use of the MEQ-CA to assess circadian preference in children and adolescents.

Using a psychophysical approach to identify a user's self selected thermal comfort on a task chair

It is understood that posture and support affect discomfort and consequently have received widespread attention from researchers. Another factor that could contribute to comfort is the thermal influence due to interaction between the human and the seating surface for which literature is limited. The primary focus of this research was to identify a user's self-selected thermal comfort on a traditional foam-based seat pan while performing a typing/mousing/reading task. A psychophysical approach was applied to evaluate the thermal influence of a task chair with the seat pan temperature as the objective variable. The method of adjustments protocol used two testing sessions with different initial settings. Results of the preliminary study with 10 female participants between 30 and 45 years indicated that the psychophysical methodology is applicable for the purpose. Results also indicate that users' self-selected comfort was achieved when the average temperature of the seat-pan interface was lower than the participant's oral body temperature. Relevance to industryProperties of seat pan materials should be considered by chair designers, which could help alleviate the thermal discomfort experienced by chair users.

Investigation of the Changes in Performance Measurements Based on Circadian Rhythm

The aim of this study was to investigate the circadian changes in some physical performance measurements. A total of 25 male volunteer university students (athletes) participated in the study. The athletes were subjected to simple and multiple reaction time, flexibility, vertical jump, dynamic and static balance tests on three different days and periods of time (09.00am, 14.00 pm and 19.00 pm). Oral body temperatures of the subjects were measured prior to each test. As a conclusion, when visual simple and multiple reaction time values were analyzed, the best results were at 09.00. For flexibility and jumping parameters, a gradual increase was seen between morning and evening with an increase in body temperature. In addition, it can be said that in studies conducted on athletes, measurement hours should be chosen carefully based on the parameters to be measured in order to get more correct and reliable results.

Decreased serotonin2C receptor responses in male patients with schizophrenia

Serotonin (5-HT)2C receptors in brain affect psychosis, reward, substance abuse, anxiety, other behaviors, appetite, body temperature, and other physiological measures. They also have been implicated in antipsychotic drug efficacy and side effects. We previously reported that the hyperthermia following administration of MK-212, a predominantly 5-HT2C receptor agonist, was diminished in a small sample of patients with schizophrenia (SCH), suggesting decreased 5-HT2C receptor responsiveness. We have now studied the responses to oral MK-212 and placebo in a larger sample of unmedicated male SCH (n=69) and normal controls (CON) (n=33), and assessed the influence of comorbid substance abuse (SA) on oral body temperature, behavioral responses, etc. The placebo-adjusted oral body temperature response to MK-212 was significantly lower in SCH compared to CON and not significantly different between the SCH with or without SA. Some behavioral responses to MK-212, e.g. self-rated feelings of increased anxiety, depression and decreased calmness, or good overall feeling, were significantly lower in the SCH patients compared to CON. These results add to the evidence for diminished 5-HT2C receptor responsiveness in SCH patients compared to CON and are consistent with reported association of HTR2C polymorphisms, leading to decreased expression or function of the HTR2C in patients with SCH.

Effect Of Controlled Room Temperature On Oral And Axillary Body Temperature Among Healthy Young People.

Effect Of Controlled Room Temperature On Oral And Axillary Body Temperature Among Healthy Young People.

Effect of controlled room temperature on oral and axillary body temperature among healthy young people

Effect of controlled room temperature on oral and axillary body temperature among healthy young people

Effects of the TRPV1 antagonist ABT‐102 on body temperature in healthy volunteers: pharmacokinetic/ pharmacodynamic analysis of three phase 1 trials

To characterize quantitatively the relationship between ABT-102, a potent and selective TRPV1 antagonist, exposure and its effects on body temperature in humans using a population pharmacokinetic/pharmacodynamic modelling approach. Serial pharmacokinetic and body temperature (oral or core) measurements from three double-blind, randomized, placebo-controlled studies [single dose (2, 6, 18, 30 and 40 mg, solution formulation), multiple dose (2, 4 and 8 mg twice daily for 7 days, solution formulation) and multiple-dose (1, 2 and 4 mg twice daily for 7 days, solid dispersion formulation)] were analyzed. NONMEM was used for model development and the model building steps were guided by pre-specified diagnostic and statistical criteria. The final model was qualified using non-parametric bootstrap and visual predictive check. The developed body temperature model included additive components of baseline, circadian rhythm (cosine function of time) and ABT-102 effect (Emax function of plasma concentration) with tolerance development (decrease in ABT-102 Emax over time). Type of body temperature measurement (oral vs. core) was included as a fixed effect on baseline, amplitude of circadian rhythm and residual error. The model estimates (95% bootstrap confidence interval) were: baseline oral body temperature, 36.3 (36.3, 36.4)°C; baseline core body temperature, 37.0 (37.0, 37.1)°C; oral circadian amplitude, 0.25 (0.22, 0.28)°C; core circadian amplitude, 0.31 (0.28, 0.34)°C; circadian phase shift, 7.6 (7.3, 7.9) h; ABT-102 Emax , 2.2 (1.9, 2.7)°C; ABT-102 EC50 , 20 (15, 28) ng ml(-1) ; tolerance T50 , 28 (20, 43) h. At exposures predicted to exert analgesic activity in humans, the effect of ABT-102 on body temperature is estimated to be 0.6 to 0.8°C. This effect attenuates within 2 to 3 days of dosing.