Human Sex Differences in Extreme Isolation

1975 ◽  
Vol 40 (2) ◽  
pp. 387-391 ◽  
Author(s):  
Gary McClure ◽  
Donald G. Forgays

This report compares the responses of male and female adult subjects in the water-immersion sensory-isolation environment. Endurance, subjective time estimates, and heart rate were dependent variables. Duration under water, with voluntary termination possible, was an average of about 4 hr. for both males and females. Subjective estimate of total time in isolation averaged about 3 ½ hr. for females and almost 4 hr. for males. Subjective time estimate of consecutive 30-min. time intervals was a bit more than 30 min. for males and about 33 min. for females. Mean heart rate (beats/minute) averaged in the 80s for both groups. None of these differences is statistically significant. This study clarifies the mixed findings reported in the literature as to sex differences in isolated environments.

2009 ◽  
Vol 296 (6) ◽  
pp. H1907-H1913 ◽  
Author(s):  
Shuqin Xing ◽  
Shirng-Wreng Tsaih ◽  
Rong Yuan ◽  
Karen L. Svenson ◽  
Linda M. Jorgenson ◽  
...  

Understanding the genetic influence on ECG time intervals and heart rate (HR) is important for identifying the genes underlying susceptibility to cardiac arrhythmias. The objective of this study was to determine the genetic influence on ECG parameters and their age-related changes in mice. ECGs were recorded in lead I on 8 males and 8 females from each of 28 inbred strains at the ages of 6, 12, and 18 mo. Significant interstrain differences in the P-R interval, QRS complex duration, and HR were found. Age-related changes in the P-R interval, QRS complex duration, and HR differed among strains. The P-R interval increased with age in 129S1/SvlmJ females. The QRS complex duration decreased with age in C57BR/J males and DBA2/J females but increased in NON/ShiLtJ females. HR decreased in C57L/J females and SM/J and P/J males but increased in BALB/cByJ males. Differences between males and females were found for HR in SJL/J mice and in the P-R interval in 129S1/SvlmJ mice. Broad-sense heritability estimates of ECG time intervals and HR ranged from 0.31 for the QRS complex duration to 0.52 for the P-R interval. Heritability estimates decreased with age for the P-R interval. Our study revealed that genetic factors play a significant role on cardiac conduction activity and age-related changes in ECG time intervals and HR.


1998 ◽  
Vol 86 (1) ◽  
pp. 19-22 ◽  
Author(s):  
William F. Vitulli ◽  
Kathleen A. Crimmins

A systematic replication of Vitulli and Shepard's 1996 study showed that a change in response requirements (verbal estimation) from circling time intervals on a scoring sheet in the older study to writing subjective time estimates in the present study did not alter the robust effects of a delay in retrospective judgement. A complete 2×2×2 factorial analysis of variance showed main effects for rate (fast versus slow) of stimulus (random digits, 1–5) presentation and delay of estimate (immediate versus remote), yet there were no interactions among rate, delay, or sex. The interpolation of “filler tasks” between the end of the target interval and subjective estimate of the duration of the target interval significantly increased perceived time compared to estimates made immediately after the target interval.


2009 ◽  
pp. 69-75 ◽  
Author(s):  
CC Hoppe ◽  
KM Moritz ◽  
SM Fitzgerald ◽  
JF Bertram ◽  
RG Evans

The novel environment of a metabolic cage can be stressful for rodents, but few studies have attempted to quantify this stressresponse. Therefore, we determined the effects on mean arterial pressure (MAP) and heart rate (HR), of placing mice of both sexes in metabolism cages for 2 days. After surgical implantation of a carotid artery catheter mice recovered individually in standard cages for 5 days. Mice then spent 2 days in metabolism cages. MAP and HR were monitored in the standard cage on Day 5 and in metabolism cages on Days 6-7. MAP increased by 18±3 and 22±4 %, while HR increased by 27±4 and 27±6 %, in males and females, respectively, during the first hours after cage switch. MAP decreased to baseline in the fourth and eighth h following metabolism cage switch in males and females, respectively. However, HR remained significantly elevated in both sexes during the entire two-day period in metabolism cages. Females had lower MAP than males both pre- and postmetabolism cage switch, but there were no sex differences in HR. These results demonstrate sustained changes in cardiovascular function when mice are housed in metabolism cages, which could potentially affect renal function.


2021 ◽  
Vol 28 (11) ◽  
pp. 1539-1545
Author(s):  
Saleemullah Abro ◽  
Quratullain Saleem ◽  
Jahanzaib Lashari ◽  
Soofia Nigar ◽  
Ghazala Masood Farrukh ◽  
...  

Objective: To evaluate the gender based comparison of blood pressure and heart rate in adolescent population. Study Design: Comparative Cross Sectional Study. Setting: Department of Physiology, Baqai Medical University. Period: 15 February to 15 August in 2017. Material & Methods: A total of 500 student of MBBS, BDS and DPT of Baqai medical university were enrolled in this study by non-probabilty, purposive sampling, after taking ethical approval. Blood pressure was measured by using stethoscope and mercury sphygmomanometer, which is applied to the arm. Heart rate is measured by palpating the radial artery. This collected data were analyzed by using SPSS version 22.0.This data of male and female adolescents were analyzed separately due to autonomic regulation. Results: It was observed that Gender based comparison of mean weight, mean body mass index (BMI), mean Systolic Blood Pressure, mean Diastolic Blood Pressure, and mean heart rate between males and females had statistically significant (p-value<0.05) differences. Among the categories of Diastolic Blood Pressure, only mean Normotensive blood pressure comparison in males and females showed statistically significant (p-value<0.05) difference, while Age, categories of systolic blood pressure (Normotensive, Prehypertension, Hypertension) and Diastolic blood pressure (Prehypertension, Hypertension) had showed statistically non-significant (p-value>0.05) gender difference in study participants. Conclusion: In our study results the mean BMI, mean Systolic Blood Pressure, mean Diastolic Blood Pressure, and mean heart rate had statistically significant (p-value<0.05) differences in gender.


1992 ◽  
Vol 15 (3) ◽  
pp. 399-410 ◽  
Author(s):  
Christopher F. Sharpley

Heart rate reactivity to a 2 minute mental arithmetic stressor delivered under timed and competitive conditions and graded for age-related difficulty was collected on 148 males and 153 females grouped into five age cohorts ranging from 7 to 20 years. Data on resting heart rate, heart rate during the stressor period, and post-stressor recovery showed significant sex (females had higher heart rates) and age effects (there was a general decrease in heart rate with age). There were no significant interactions between age and sex. Mean heart rate reactivity also showed significant variation with age, but no significant differences between males and females, nor any significant interaction between age and sex. The age effect for heart rate reactivity appeared to be a result of the oldest age group having significantly greater increases in heart rate than all other age groups.


2009 ◽  
Vol 23 (2) ◽  
pp. 77-84 ◽  
Author(s):  
Matthew C. Whited ◽  
Kevin T. Larkin

Sex differences in cardiovascular reactivity to stress are well documented, with some studies showing women having greater heart rate responses than men, and men having greater blood pressure responses than women, while other studies show conflicting evidence. Few studies have attended to the gender relevance of tasks employed in these studies. This study investigated cardiovascular reactivity to two interpersonal stressors consistent with different gender roles to determine whether response differences exist between men and women. A total of 26 men and 31 women were assigned to either a traditional male-oriented task that involved interpersonal conflict (Conflict Task) or a traditional female-oriented task that involved comforting another person (Comfort Task). Results demonstrated that women exhibited greater heart rate reactions than men independent of the task type, and that men did not display a higher reactivity than women on any measure. These findings indicate that sex of participant was more important than gender relevance of the task in eliciting sex differences in cardiovascular responding.


1999 ◽  
Vol 276 (2) ◽  
pp. R500-R504 ◽  
Author(s):  
Ping Li ◽  
Steven H. Sur ◽  
Ralph E. Mistlberger ◽  
Mariana Morris

The circadian pattern of mean arterial pressure (MAP) and heart rate (HR) was measured in C57BL mice with carotid arterial catheters. Cardiovascular parameters were recorded continuously with a computerized monitoring system at a sampling rate of 100 Hz. The tethered animals were healthy, showing stabilized drinking and eating patterns within 2 days of surgery and little loss of body weight. Analysis of the 24-h pattern of MAP and HR was conducted using data from 3–6 consecutive days of recording. A daily rhythm of MAP was evident in all mice, with group mean dark and light values of 101.4 ± 7.3 and 93.1 ± 2.9 mmHg, respectively. The group mean waveform was bimodal, with peak values evident early and late in the dark period, and a trough during the middle of the light period. The phase of maximum and minimum values showed low within-group variance. Mean heart rate was greater at night than during the day (561.9 ± 22.7 vs. 530.3 ± 22.3 beats/min). Peak values generally occurred at dark onset, and minimum values during the middle of both the dark and the light periods. We conclude that it is possible to perform measurements of circadian cardiovascular parameters in the mouse, providing new avenues for the investigation of genetic models.


2020 ◽  
Vol 4 (Supplement_1) ◽  
pp. 313-313
Author(s):  
Brianne Olivieri-Mui ◽  
Sandra Shi ◽  
Ellen McCarthy ◽  
Dae Kim

Abstract Frailty may differentially impact how older adult males and females perceive sexual functioning, an important part of well-being. We assessed the level of frailty (robust, pre-frail, frail) for anyone with data on 11 sexual functioning questions asked in wave 2 of the National Social Life, Health, and Aging Project, 2010-2011 (n=2060). Questions covered five domains: overall sexual function (OSF), sexual function anxiety (SFA), changes in sexual function (CSF), erectile/vaginal dysfunction (EVD), and masturbation. Logistic regression identified sex differences in frailty and reporting worse sexual functioning. Linear regression predicted the number of domains reported as worse. Among males (n=1057), pre-frailty meant higher odds of reporting SFA (OR 1.8 95%CI 1.2-6.6), CSF (OR 1.7 95%CI 1.1-2.7), and EVD (OR 1.5 95%CI 1.0-2.2). Among females (n=1003), there was no difference in reporting by frailty. Females were more likely to report worse OSF (Robust: OR 7.4, 95%CI 4.8-11.4; Pre-frail: OR 6.2, 95%CI 3.9-9.9; Frail: OR 3.4 95%CI 1.7-6.6), but less likely to report SFA (Robust OR .3, 95%CI .2-.5; Pre-frail OR .2, 95%CI .1-.3; Frail OR .2 95%CI .1-.3). Pre-frail and frail females reported fewer domains as worse (Pre-frail coefficient -0.21 SE 0.09, Frail -0.43 SE 0.14). As frailty worsened, males reported more domains as worse (Pre-frail 0.24 SE 0.07, Frail 0.29 SE 0.08). Self-reported sexual functioning differs by sex at all levels of frailty, and reporting by males, but not females, changes with frailty. Providers should be aware that sexual functioning is of importance to both sexes despite varying degrees of frailty.


2021 ◽  
pp. svn-2020-000834
Author(s):  
Koteswara Rao Nalamolu ◽  
Bharath Chelluboina ◽  
Casimir A Fornal ◽  
Siva Reddy Challa ◽  
David M Pinson ◽  
...  

Background and purposeThe therapeutic potential of different stem cells for ischaemic stroke treatment is intriguing and somewhat controversial. Recent results from our laboratory have demonstrated the potential benefits of human umbilical cord blood-derived mesenchymal stem cells (MSC) in a rodent stroke model. We hypothesised that MSC treatment would effectively promote the recovery of sensory and motor function in both males and females, despite any apparent sex differences in post stroke brain injury.MethodsTransient focal cerebral ischaemia was induced in adult Sprague-Dawley rats by occlusion of the middle cerebral artery. Following the procedure, male and female rats of the untreated group were euthanised 1 day after reperfusion and their brains were used to estimate the resulting infarct volume and tissue swelling. Additional groups of stroke-induced male and female rats were treated with MSC or vehicle and were subsequently subjected to a battery of standard neurological/neurobehavioral tests (Modified Neurological Severity Score assessment, adhesive tape removal, beam walk and rotarod). The tests were administered at regular intervals (at days 1, 3, 5, 7 and 14) after reperfusion to determine the time course of neurological and functional recovery after stroke.ResultsThe infarct volume and extent of swelling of the ischaemic brain were similar in males and females. Despite similar pathological stroke lesions, the clinical manifestations of stroke were more pronounced in males than females, as indicated by the neurological scores and other tests. MSC treatment significantly improved the recovery of sensory and motor function in both sexes, and it demonstrated efficacy in both moderate stroke (females) and severe stroke (males).ConclusionsDespite sex differences in the severity of post stroke outcomes, MSC treatment promoted the recovery of sensory and motor function in male and female rats, suggesting that it may be a promising treatment for stroke.


2021 ◽  
Vol 80 (Suppl 1) ◽  
pp. 8.1-8
Author(s):  
G. Robinson ◽  
K. Waddington ◽  
J. Peng ◽  
A. Radziszewska ◽  
H. Peckham ◽  
...  

Background:Males and females have altered immune responses resulting in variation in autoimmune and cardiovascular disease risk (CVR). Recently, these differences have played a role in the inflammatory response to COVID-19. Sex differences exist in the frequency and activity of immune-cell subsets but mechanisms underlying sexual dimorphism remain unknown. Juvenile-onset systemic lupus erythematosus (JSLE) is an autoimmune disorder that commonly emerges during puberty, has a strong female prevalence (female:male ratio, 4.5:1) and results in an increased CVR. JSLE is characterised by chronic inflammation and dyslipidaemia, where cardiovascular disease is a leading cause of mortality for patients. Our previous work identified a link between immune cell function and lipid metabolism in adult-onset SLE. We hypothesised that sex hormones could influence both lipid metabolism and immune cell function and this could determine sex-specific susceptibility to JSLE and associated CVR.Objectives:We investigated the role of sex hormones in modifying systemic lipid metabolism and inflammation.Methods:Nuclear magnetic resonance spectroscopy based serum metabolomics measuring over 130 lipoproteins (14-subsets with lipid compositions), flow cytometry measuring immune-cells, and RNA-sequencing were used to assess the metabolic and immune profile in young, pre/post-pubertal males (n=10/17) and females (n=10/23) and in individuals with gender-dysphoria (GD) under cross-hormone treatment (trans-male/female, n=26/25). This analysis was also performed on a cohort of post-pubertal male (n=12) and female (n=23) JSLE patients. Data was analysed by logistic regression, balanced random forest machine learning (BRF-ML), differential gene expression (DEG) and pathway analysis.Results:Post-pubertal males had significantly reduced cardio-protective high-density lipoprotein (HDL) subsets (p<0.0001) and increased cardio-pathogenic very-low-density lipoprotein subsets (p<0.0001) compared to females. These differences were not observed pre-puberty and were reversed significantly by cross-hormone treatment in GD individuals, suggesting that sex hormones regulate lipid metabolism in-vivo.BRF-ML (28 immune-cell subsets) identified an increased frequency of anti-inflammatory regulatory T-cells (Tregs) in post-pubertal males compared to females (p=0.0097). These Tregs were also more suppressive in males compared to females. Differences in Treg frequency were seen pre-puberty and were not altered by sex hormone treatment in GD individuals. However, Treg DEGs and functional transcriptomic pathways altered between post-pubertal males and females, including those involved in inflammatory signalling, overlapped with those altered by hormones in GD, suggesting hormones may also drive Treg functional changes. In addition, HDL metabolites modified by hormones showed differential associations with Treg phenotypes between post-pubertal males and females.Strikingly, sex differences in lipoproteins and Tregs were lost in JSLE, suggesting hormone signalling could be dysregulated in the pathogenesis of autoimmunity and could increase CVR for patients.Conclusion:Sex hormones drive altered lipoprotein metabolism and functional transcriptomic pathways in Tregs. Males have a lipoprotein profile associated with increased CVR, but a more anti-inflammatory immune profile compared to females. Together, this could explain sex differences in inflammatory disease susceptibilities and inform future sex-specific therapeutic strategies for the management of both JSLE and CVR.Acknowledgements:Lupus UKRosetrees TrustVersus ArthritisNIHR UCLH Biomedical Research CentreDisclosure of Interests:None declared


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