Optimal Activity Levels Research Articles

Optimal levels of sleep, sedentary behaviour, and physical activity needed to support cognitive function in children of the early years

BackgroundSleep, sedentary behaviour, physical activity, and the composition of these movement behaviours across the 24-h day are associated with cognitive function in early years children. This study used a Goldilocks day compositional data analysis approach to identify the optimal duration of sleep, sedentary behaviour, light physical activity, and moderate-to-vigorous physical activity associated with desired cognitive function outcomes in early years children.MethodsThis cross-sectional study included 858 children aged 2.8–5.5 years from the Sleep and Activity Database for the Early Years. 24-h movement behaviours (sleep, sedentary behaviour, light physical activity, moderate-to-vigorous physical activity) were measured using ActiGraph accelerometers. Cognitive function was measured using three tasks from the Early Years Toolbox: visual-spatial working memory, response inhibition, and expressive vocabulary. A Goldilocks day compositional data analysis approach was used in R software to identify the optimal time-use compositions associated with the best 10% of the cognitive function scores.ResultsThe movement behaviour composition and the relative time spent in sleep and sedentary behaviour but not different intensities of physical activity were significantly associated with working memory (P ≤ 0.01). The movement behaviour composition and relative time spent in sleep, sedentary behaviour, and different intensities of physical activity were not significantly associated with response inhibition or expressive vocabulary (P > 0.2). Therefore, optimal time use was only determined for working memory. Optimal daily durations for working memory were observed with 11:00 (hr:min) of sleep, 5:42 of sedentary behaviour, 5:06 of light physical activity, and 2:12 of moderate-to-vigorous physical activity.ConclusionWorking memory was the only cognitive function outcome related to the 24-h movement behaviour composition. Optimal sleep for working memory was consistent with current recommended durations, while optimal moderate-to-vigorous physical activity greatly exceeded minimal recommended levels. Optimal sedentary behaviour was longer and light physical activity was shorter than the sample average.

Balancing benefits and risks of exercise in pregnancy: a qualitative analysis of social media discussion

Exercise improves pregnancy outcomes, but few pregnant individuals meet physical activity guidelines. The main objective of this study was to explore the perception of exercise during pregnancy using posts and...

Влияние физической нагрузки различной интенсивности на когнитивные способности студентов

There is increasing evidence that physical activity positively affects cognitive function. Physical exercise activates molecular systems involved in metabolism and synaptic plasticity, and the interaction between these systems has been shown to influence cognitive function. The challenge for the scientific community is to find an optimal level of physical activity for students that will promote harmonious development and enhance the effectiveness of their academic performance. This article highlights the influence of various intensities of physical activity on the dynamics of intelligence indicators in male and female students. In the process of the pedagogical experiment, the students were distributed into two groups according to a certain mode of physical activity. The classes in the experimental group included exercises of high intensity, while the classes in the control group included mainly exercises of low intensity. Intellectual abilities were measured before and after 2 months of the pedagogical experiment. The Raven's Standardized Performance Matrices (SPM) test was used to assess intellectual abilities. The results of the study showed that the increase in intelligence indicators in the students of the experimental group is statistically significant, in contrast to the control group. At the same time, it was not possible to identify significant differences using ANOVA. The obtained data are useful in the context of further research, as they show specialists engaged in the study and development of the cognitive abilities of students, different possibilities of influence and a certain range in the organization of further.

Optimal level of human intracranial theta activity for behavioral switching in the subthalamo-medio-prefrontal circuit

The ability to switch between rules associating stimuli and responses depend on a circuit including the dorsomedial prefrontal cortex (dmPFC) and the subthalamic nucleus (STN). However, the precise neural implementations of switching remain unclear. To address this issue, we recorded local field potentials from the STN and from the dmPFC of neuropsychiatric patients during behavioral switching. Drift-diffusion modeling revealed that switching is associated with a shift in the starting point of evidence accumulation. Theta activity increases in dmPFC and STN during successful switch trials, while temporally delayed and excessive levels of theta lead to premature switch errors. This seemingly opposing impact of increased theta in successful and unsuccessful switching is explained by a negative correlation between theta activity and the starting point. Together, these results shed a new light on the neural mechanisms underlying the rapid reconfiguration of stimulus-response associations, revealing a Goldilocks’ effect of theta activity on switching behavior.

Outcomes of Painful Hips After Hip Arthroscopy Surgery for Femoroacetabular Impingement.

The benefits of hip arthroscopic surgery for femoroacetabular impingement are well-established. Hip arthroscopic surgery rates have risen dramatically over the last decade. Some patients, however, may continue to experience hip symptoms after surgery and are dissatisfied with their inability to return to desired optimal activity levels. The purpose of the study is to understand the long-term outcomes of patients with painful hips after hip arthroscopy for femoroacetabular impingement. This is a retrospective study of the outcomes of painful hips after hip arthroscopy for femoroacetabular impingement, with four to 14-year follow-up from 2008 to 2022. A total of 84 hip arthroscopies were performed. Most of the patients had labral tear debridement and shaving of the aspherical femoral head also known as cam lesion, and five patients had repair for labral tear. There were eight patients who had bilateral hip involvement. There were 27 men and 57 females between the second to fifth decades. The electronic patient's records and radiological images were reviewed, and patient outcomes were graded as pain-free hip (asymptomatic) or painful hip (persistent pain and symptoms of instability). After hip arthroscopy surgery, 55% (46) of hips were graded pain-free in patients who were mostly in their 20s and 30s, while 45% (38) of hips had persistent pain. These patients were in their third or fifth decade. In the painful hip cohort, 33 patients had one hip arthroscopic surgery, while five patients had multiple repeat hip arthroscopies in the same hip over a three to six-year period. Bilateral hip arthroscopies were performed at different times in eight patients of which five individuals experienced painful hip outcomes. There were seven females and one male in their 30s and 40s. The labral tear was repaired in five patients, and two patients had painful hip outcomes. Both were females in their 20s and 30s. Patients with chronic painful hips after hip arthroscopic surgery were investigated to identify the cause of the pain. If no cause was established, then they were finally referred to pain specialist clinicians for pain management. This cohort had seven patients between 28 and 43 years. Six were female and one was male. Total hip replacement (THR) was performed in four patients (4.7%). Conversely, 95.3% of patients did not need THR during the study period of 14 years. Hip arthroscopy can be an effective treatment for femoroacetabular impingement. Careful patient selection and a holistic approach are vital for a good patient outcome. The success rate of the pain-free hip after hip arthroscopy decreases with increasing age of the patient, particularly in the female gender.Patients with grade II and more degenerative chondral changes do not perform well. Patients in their fourth and fifth decade can benefit from hip arthroscopy provided a comprehensive discussion of the expected outcomes is conducted prior to surgery. Overall, hip arthroscopy remains a valuable tool, but it is important to be conscious of its limitations and potential challenges.

Altering adult Hippocampal Neurogenesis in the dentate gyrus through varying glucocorticoid receptor concentrations

Adult Hippocampal Neurogenesis, short for AHN, is an essential yet foundational process of producing new nerve cells in the dentate gyrus of the hippocampus. It is a fact that increasing AHN will enhance peoples ability to learn, memorize, regulate mood, etc. Therefore, scientists strive to pursue the factors which influence AHN. Until now, research had proved that GR activity is associated with the degree of AHN. Additionally, a high GR activity will potentially reduce the level of ANH and an optimal level of GR activity will create the optimized level of AHN. Consequently, how a low level of GR activity will possibly influence AHN will be examined in this paper. For Experiment 1, the GR antagonist reduces the GR activity in 8-year-old male mice: C57BL/6 and BrdU highlights the newly generated neurons in the dentate gyrus. As an ideal result compared to the control group, low GR activity will lead to a decrease in the AHN. For Experiment 2, 3 minor experiments will be constructed to test the GR activity and AHN of the mice in 3 different conditions (low, controllable, and uncontrollable stress). And Nanobit Assay that is separately attached to the GR and the ligands will present fluorescent when combined. Additionally, the method of CRISPR-CAS9 is used to knock down either GR or GR when the other one is measured, and BrdU is also used to light up the neurons to measure the degree of AHN. The ideal result will present a number greater than 1 for the ratio between GR/GR and AHN decreases for the low-stress group and uncontrollable-stress group. Oppositely, the ratio will be smaller than 1 for the controllable stress group, meaning AHN increases. Conclusively, the output will demonstrate a reversed U shape with the x-axis being the level of GR activity and the y-axis presenting the level of AHN. Despite the experiments that have proceeded on mice, the significance of them is people will have certain references to the influences of AHN to prevent those conditions or stress which will negatively affect AHN.

Cross-sectional association of physical activity levels with risks of sarcopenia among older Taiwanese adults

ObjectivesThe updated World Health Organization 2020 guidelines strongly recommend an optimal physical activity level of 150–300 min/week for older adults. However, few studies have examined the relationship between different levels of physical activity and sarcopenia. Therefore, the purpose of this study was to investigate the cross-sectional associations between overall physical activity levels, gender, intensity, and the risk of sarcopenia among older Taiwanese adults.MethodsA nationwide cross-sectional telephone survey of older adults (≥ 65 years) was conducted in Taiwan from October 2019 to January 2020. Participants were interviewed to collect self-reported data on their level of physical activity (measured by the Taiwanese version of the IPAQ-SF), sarcopenia risk (measured by the SARC-F questionnaire), and sociodemographics.ResultsA total of 1068 older adults were surveyed. Compared with the optimal physical activity level recommendations in the WHO guidelines and after adjusting for potential confounders and proposing an association independent of sedentary behavior, older adults with insufficient physical activity levels (< 150 min/week) were more likely to have a higher risk of sarcopenia (OR: 3.24; CI: 1.67–6.27), whereas older adults who exceeded physical activity guidelines (> 300 min/week) were more likely to have a lower risk of sarcopenia (OR: 0.39; CI: 0.20–0.78). Maintaining moderate-intensity physical activity is essential for older adults, as physical activity that exceeds the guidelines can significantly lower the risk of sarcopenia; meanwhile, insufficient physical activity can greatly increase it. Also, there seems to be a similar association between sarcopenia risk across different physical activity levels in vigorous-intensity physical activities in older adults. However, due to the small number of sarcopenia-risk participants who met or exceeded vigorous-intensity physical activity levels, further comparisons between different vigorous-intensity physical activity levels did not show significant differences in sarcopenia risk. Additionally, insufficient physical activity was found to be an important risk factor for sarcopenia in both genders, while physical activity that exceeded the guidelines prevented sarcopenia in females.ConclusionsThe findings of this study highlight the potential dose-response relationship related to physical activity. The 2020 WHO guidelines provide the public with minimum recommendations for physical activity. However, exceeding these recommended levels appears to be more effective in preventing sarcopenia in older adults and may offer even greater health benefits. Future research should further explore whether exceeding these guidelines could result in additional health benefits.

Patient perspectives and preferences on cerclage and preterm birth: a focus group study

AimThis qualitative focus group study aims to asses cerclage-related symptoms, the impact of a cerclage on daily functioning and patient perspectives of their healthcare experience. This study extends beyond the current focus on surgical and obstetric outcomes of a cerclage, thereby contributing to a more comprehensive understanding of the challenges faced by individuals in the context of extreme preterm birth and fetal loss and the impact of a cerclage on multiple facets in life.MethodsParticipants were recruited from the Amsterdam University Medical Center, Amsterdam, the Netherlands or via the website of a Dutch patient organization for (extreme) preterm birth. Eligible participants were ≥ 18 years old with a previous vaginal and/or abdominal cerclage with a subsequent delivery at ≥ 34 weeks of gestation with neonatal survival. Two focus group discussions (FGD) were performed. A predefined format was used, which was identical for both the vaginal and abdominal cerclage group. The International Classification of Functioning, Disability and Health (ICF-DH) was used to provide structure. Outcomes were a broad range of participants reported perspectives on physical, emotional, and social-related quality of life.ResultsIn the Vaginal Cerclage Group (VCG) and Abdominal Cerclage Group (ACG), respectively, 11 and 8 participants were included. Fear for a subsequent pregnancy loss was the most limiting factor to perform daily activities during pregnancy in all participants with a cerclage. Fear to conceive again because of prior second-trimester fetal loss was experienced by 27% in the VCG and 13% in the ACG. The majority of participants experienced a reduction in anxiety after placement of their cerclage (VCG = 64%, ACG = 75%). Decreased mobility/bedrest (VCG = 100%, ACG = 75%) and blood loss (VCG = 55%, ACG = 13%) were frequently mentioned complaints during pregnancy with cerclage. Other aspects mentioned in both groups were social isolation, the lack of societal participation, and the perceived need to quit work and sports. All participants in the abdominal cerclage group reported a lack of comprehensible and unambiguous information about obstetric management and expectations during pregnancy in secondary care hospitals. Clear communication between secondary and tertiary care hospitals about obstetric management following an abdominal cerclage, for example, about the need for cervical length measurements by ultrasound, the need for bedrest or advice concerning sexual activity was missing (63%). Psychologic support was desired in half of all participants, but was not offered to them.ConclusionsThe fear of a subsequent pregnancy loss was reported as the most limiting factor in daily life by all participants. Cerclage placement resulted in the reduction of anxiety. Participants mentioned a significant impact of bedrest and activity restriction during pregnancy with cerclage on social participation and daily activities. Unfortunately, no high level evidence is available on this matter. Patients might even benefit from appropriate levels of physical activity throughout their pregnancy to promote their overall well-being. More evidence is needed to determine the optimal level of physical activity. There is a need for clear and unambiguous patient information about obstetric management.

Dose-response relationship between weekly physical activity level and the frequency of colds in Chinese middle-aged and elderly individuals.

Engaging in appropriate physical activity can significantly lower the risk of various diseases among middle-aged and older adults. Investigating optimal levels of physical activity (PA) is crucial for enhancing the health of this demographic. This study aims to explore the dose-response relationship between weekly PA levels and the frequency of colds among Chinese middle-aged and elderly individuals, identifying the necessary PA level to effectively diminish the risk of colds. We conducted a cross-sectional study using a web-based survey targeting individuals aged 40 and older (n=1,683) in China. The survey collected information on PA and the frequency of colds. Data was analyzed using Kruskal-Wallis test and the χ2 test. We explored the dose-response relationship between weekly PA and cold frequency over the past year through an ordered multivariate logistic regression model and a restricted cubic spline model. (1) Brisk walking emerged as the preferred physical exercise for those over 40. The findings suggest that engaging in moderate (odds ratio (OR) = 0.64, P<0.001, 95% confidence interval (CI) [0.50-0.81]) and high (OR = 0.64, P<0.001, 95% CI [0.51-0.79]) levels of PA weekly significantly reduces the risk of catching a cold. Individuals with one (OR = 1.47, P<0.001, 95% CI [1.20-1.80]) or multiple chronic diseases (OR = 1.56, P<0.001, 95% CI [1.21-2.00]) were at increased risk. Those residing in central (OR = 1.64, P<0.001, 95% CI [1.33-02.01]) and western China (OR = 1.49, P = 0.008, 95% CI [1.11-02.00]) faced a higher risk compared to their counterparts in eastern China. (2) According to the restricted cubic spline model, adults who experienced one cold in the past year had a weekly PA level of 537.29 metabolic equivalent-minutes per week (MET-min/wk) with an OR value of 1. For those reporting two or more colds, the PA level was 537.76 MET-min/wk with an OR of 1. (1) Brisk walking is the most favored exercise among the Chinese middle-aged and elderly, with the prevalence of colds being affected by the number of chronic diseases and the geographic location. (2) Regular, moderate exercise is linked to a lower risk of colds. To effectively reduce cold frequency, it is recommended that middle-aged and elderly Chinese individuals engage in a minimum of 538 MET-min/wk of exercise.

Enhancing Growth and Intestinal Health in Triploid Rainbow Trout Fed a Low-Fish-Meal Diet through Supplementation with Clostridium butyricum

Enhancing Growth and Intestinal Health in Triploid Rainbow Trout Fed a Low-Fish-Meal Diet through Supplementation with Clostridium butyricum

The Optimal Cut-Off Point of Physical Activity for the Prevention of Childhood Overweight and Obesity.

Childhood obesity might threaten children's current and adulthood health outcomes. Previous studies have illustrated the positive effects of physical activity on weight control; however, there is a lack of evidence on the optimal dose of physical activity. Therefore, we aimed to explore the relationship between physical activity and overweight and obesity, as well as the optimal threshold for physical activity. The median (interquartile range) and number (proportion) were used to describe the statistics. The Mann-Whitney U test and chi-square test were used for an univariable analysis. The generalized additive model with a smooth function was used to depict the preliminary relationship between physical activity and overweight and obesity. The cut-off level of physical activity was identified using AddFor algorithms, and a logistic regression model was applied to explore the multivariable relationship between physical activity and overweight and obesity after adjusting for control variables. According to the statistical analyses, 24.3% of 842 children and adolescents had overweight and obesity. The average number of days that the participants engaged in more than one hour of physical activity was three days a week. The optimal cut-off level of physical activity for the prevention of childhood overweight and obesity was 4 times a week. The participants who exercised more than four times a week (AOR(95% CI) = 0.56(0.38, 0.83), p = 0.004) were less likely to be overweight and obese. In the context of the general lack of physical activity among children and adolescents, we recommend that children and adolescents engage in 60 min of physical activity more than four times a week for a healthy weight.

Association between accelerometer-derived physical activity and depression: a cross-sectional study using isotemporal substitution analysis

ObjectivesDepression is a significant public health concern, and physical activity has been identified as a non-pharmacological intervention. Understanding the dose–response relationship between physical activity and depression is crucial for designing...

No Panic in Pandemic: The Impact of Individual Choice on Public Health Policy

Problem definition: Public health interventions, such as social distancing and lockdown, play an important role in containing infectious disease outbreaks, such as coronavirus disease 2019 (COVID-19). Yet, these interventions could cause significant financial losses because of the disruption to regular socioeconomic activities. Moreover, an individual’s activity level is influenced not only by public health policies but also by one’s perception of the disease burden of infection. Strategic planning is required to optimize the timing and intensity of these public health interventions by considering individual responses. Methodology/results: We use the multinomial logit choice model to characterize individual reactions to the risk of infection and public health interventions and integrate it into a repeated Stackelberg game with the susceptible-infected-recovered disease transmission dynamics. We find that the individual equilibrium activity level is higher than the socially optimal activity level because of an individual’s ignorance of the negative externality imposed on others. As a result, implementing lockdown and social distancing policies at moderate disease prevalence may be equivalently critical, if not more, compared with their implementations when the disease prevalence is at its peak level. To verify these findings, we conduct numerical studies based on representative COVID-19 data in Minnesota. Managerial implications: Our results call for policymakers’ attention to consider the impact of individuals’ responses in the planning for different pandemic containment measures. Individuals’ responses in the pandemic may significantly affect the optimal implementation of lockdown and social distancing policies. Supplemental Material: The online appendix is available at https://doi.org/10.1287/msom.2022.0514 .

ADAPTATION OF TECHNOLOGIES FOR THE FORMATION OF MOTOR ACTIVITY IN THE CONDITIONS OF DISTANCE LEARNING

The article considers the issue of technology adaptation for the purpose of effective formation of motor activity in students in the conditions of distance learning. In the context of modern educational challenges related to the pandemic and the spread of distance learning, the authors explore methods and tools aimed at supporting the physical development of students in a remote environment. Examples of successful practices are considered, including the use of virtual workouts, interactive applications for physical activity and innovative approaches to creating electronic physical education lessons. The results of the study emphasize the importance of integrating technology into the learning process in order to maintain an optimal level of motor activity and take care of the physical health of students in distance learning. The authors emphasize the need to develop effective strategies to promote an active lifestyle in a virtual educational environment.

The Effect of Levels of Leisure-Time Physical Activity on Cognitive Functions Among Older Adults with Mild Cognitive Impairment: A Longitudinal Analysis.

One dementia prevention strategy that is effective for older adults is frequent participation in leisure time physical activity. However, research gaps exist in our understanding of the longitudinal relationship between different levels of leisure time physical activity participation and the cognitive function of older adults with mild cognitive impairment. Thus, we investigated this relationship using Health and Retirement Study data from 2012 to 2020. Results from Repeated Measures Multivariate Analysis of Covariance indicated that both the mid (Mean Difference = -0.45) and high level (Mean Difference = -0.82) leisure time physical activity groups showed higher levels of memory function compared to the low-level leisure time physical activity group. Additionally, the mid (Mean Difference = -0.21) and high level (Mean Difference = -0.37) leisure time physical activity groups reported better working memory function, and the mid (Mean Difference = -0.02) and high level (Mean Difference = -0.02) leisure time physical activity groups showed higher levels of attention and processing speed than the low-level leisure time physical activity group. These findings suggest that older adults with mild cognitive impairment who engage either vigorously or moderately in leisure time physical activity (more than three times a week) experience improvements in cognitive function compared to those who do not. This study provides valuable insights for clinicians on the optimal level of leisure time physical activity required to mitigate cognitive decline in older adults with mild cognitive impairment.

Association Between Leisure-Time Physical Activity and All-Cause Mortality Among Stroke Survivors: Findings From National Health and Nutrition Examination Survey.

Stroke is the second leading cause of death and the third leading cause of disability globally. But little is known about the optimal level of physical activity for stroke survivors. Therefore, we aimed to analyze the dose-response relationship between leisure-time physical activity (LTPA) and all-cause mortality in stroke survivors. One-thousand six hundred and sixty-four stroke survivors form from the 1999 to 2018 National Health and Nutrition Examination Surveys were classified into 6 groups: 0, 1 to 149, 150 to 299, 300 to 599, 600 to 899, and ≥900minutes per week (based on the Global Physical Activity Questionnaire). Cox proportional hazards regression models with different adjustments of covariates were used to investigate the association between LTPA and all-cause mortality. Except for stroke survivors with LTPA levels ranging from 600 to 899minutes per week (P = .055), there was a significant difference in survival rates among stroke survivors with different levels of LTPA compared with those without LTPA. Stroke survivors engaging in LTPA levels exceeding 900minutes per week exhibited the greatest benefit compared with stroke survivors who did not engage in LTPA (hazard ratio = 0.225; 95% confidence interval, 0.122-0.414). Our research findings add to the expanding evidence base that highlights the favorable connection between LTPA and decreased risk of all-cause mortality among individuals who have survived a stroke. Our study emphasizes the significance of incorporating physical activity interventions into the poststroke care regimen and underscores the potential advantages of personalized activity guidance.

Compliance of patients with hypertension to muscular exercise and healthy diet: a cross-sectional study from Arar, Saudi Arabia

Objective: This study aimed to examine the compliance of patients with hypertension with muscular exercise and a healthy diet in Arar, Saudi Arabia. Methods: This prospective cross-sectional study was conducted among adults diagnosed with hypertension, who were recruited from healthcare facilities in Arar. Sociodemographic data were collected alongside the questionnaires namely Rapid Assessment of Physical Activity (RAPA) for physical activity assessment and the Rapid Eating Assessment for Participants - Shortened Version (REAPS) for dietary assessment. Results: Regarding the REAPS score, 27.6% out of 387 participants had a high-quality diet, 45.7% had a moderate-quality diet, and 26.6% had a low-quality diet. However, in terms of the RAPA score, 57.4% had suboptimal physical activity, while 42.6% had optimal physical activity levels. Moreover, the RAPA score had a statistically significant relation to education level (p-value=0.035) and occupational status (p-value=0.006). It also showed a statistically insignificant relation to gender. While REAPS score had a statistically insignificant relation to gender, education level, and occupation. Conclusion: The study revealed that a significant portion of patients with hypertension had suboptimal levels of compliance with muscular exercise and a healthy diet. While a notable percentage had a moderate-quality diet, a substantial proportion exhibited low-quality diets. Additionally, the majority of participants were categorized under suboptimal physical activity levels.

Association between physical activity and depressive symptoms in adolescents: A prospective cohort study

It remains uncertain whether a protective association between physical activity and depression exists among adolescents and what the optimal level of physical activity might be. This study aimed to estimate the associations of physical activity levels with depressive symptoms and new-onset depression, while identifying potential modifying factors influencing the relationships. In this cohort study, we initially enrolled 1957 participants at baseline and followed up with 1738 of them after two years. Our analysis focused on data from 1482 students who provided complete information on both physical activity and depressive symptoms. Generalized linear regression and restricted cubic spline regression models were performed. Our adjusted models revealed that engaging in 4–7 h/week of moderate-to-vigorous physical activity (MVPA) at baseline was negatively associated with subsequent depressive symptoms and new-onset depression compared to the non-MVPA group. However, exceeding 7 h/week of MVPA did not provide substantial benefits. Furthermore, drinking and screen time potentially modified the relationship between MVPA and new-onset depression. Our findings suggest that 4–7 h of MVPA per week may be an appropriate level to reduce depressive symptoms in adolescents. Moreover, individual behaviors (e.g., drinking and screen time) warrant heightened attention in interventions targeting the reduction of depression in this population.

Effects of activity levels on aortic calcification in hyperlipidemic mice as measured by microPETmicroCT

Background and aimsCardiovascular disease risk is associated with coronary artery calcification and is mitigated by regular exercise. Paradoxically, elite endurance athletes, who have low risk, are likely to have more coronary calcification, raising questions about the optimal level of activity. MethodsFemale hyperlipidemic (Apoe−/−) mice with baseline aortic calcification were subjected to high-speed (18.5 m/min), low-speed (12.5 m/min), or no treadmill exercise for 9 weeks. 18F–NaF microPET/CT images were acquired at weeks 0 and 9, and echocardiography was performed at week 9. ResultsIn controls, aortic calcium content and density increased significantly. Exercise regimens did not alter the time-dependent increase in content, but the increase in mean density was blunted. Interestingly, the low-speed regimen significantly reduced 18F–NaF uptake, a marker of surface area. Left ventricular (LV) systolic function was lower while LV diameter was greater in the low-speed group compared with controls or the high-speed group. In the low-speed group, vertebral bone density by CT decreased significantly, contrary to expectations. Male hyperlipidemic (Apoe−/−) mice were fed a Western diet and also subjected to low-speed or no exercise followed by imaging at weeks 0 and 9. In males, exercise also did not alter the time-dependent increase in aortic calcification. Exercise did not affect 18F–NaF uptake or bone mineral density, but it blunted the diet-induced LV hypertrophy seen in controls. ConclusionsThese results suggest that, in mice, exercise has differential effects on aortic calcification, cardiac function, and skeletal bone mineral density.

Production, purification, and characterization of cold-active lipase from the psychrotroph Pseudomonas sp. A6

Cold-active lipases are presently employed extensively in the detergent, chemical intermediate, fine chemical, food, and pharmaceutical industries. Seven cold-adaptive bacteria were isolated from the Mediterranean Sea near Alexandria, Egypt, and tested for their ability to produce cold-active lipase, with the highest activity at 10 °C. The most potent isolate was Pseudomonas sp. A6. To determine the most important variables, the bacterium was exposed to a necessary medium component and environmental factor screening using a single factor-at-a-time approach, followed by a multifactorial Plackett-Burman design strategy. After purification and characterization, the optimal activity levels for the cold-active lipase were figured out. Inoculation of Pseudomonas A6 under near optimum conditions using medium consisting of (g/L) peptone 7.14; soybean oil 7.5% (v/v); K2HPO4, 0.4; MgSO4, 0.1; glucose 2; pH 8; and temperature 10 °C led to a maximum lipase activity anticipated to be 23.36 U/mL. Purified lipase showed the best activity and thermal stability at a pH of 8 and a temperature of 10 °C. The Pseudomonas A6 lipase tolerated the monovalent ions, while greater valence ions did not.