Increased heart rate accelerates norepinephrine washout from normal myocardium

1987 ◽  
Vol 253 (6) ◽  
pp. H1581-H1585 ◽  
Author(s):  
R. J. Henning ◽  
J. Cheng ◽  
A. M. Bhat ◽  
M. N. Levy
Keyword(s):  
Heart Rate ◽  
Ventricular Myocardium ◽  
Neuronal Uptake ◽  
Control Group ◽  
Inotropic Response ◽  
Sympathetic Stimulation ◽  
Uptake Mechanism ◽  
The Mean ◽  
Time Required ◽  
Experimental Group

We determined whether a change in heart rate affected the decay of the ventricular inotropic response to sympathetic stimulation in an experimental group and in a control group of anesthetized dogs. We induced complete heart block in each animal and paced the ventricles at rates of 90, 120, and 150 min-1 during two observation periods. In the experimental group, desipramine hydrochloride was given during the second period to block the neuronal uptake mechanism. The control animals did not receive desipramine during either period. The time required for the ventricular inotropic response to decay by 50% after cessation of a 2-min train of sympathetic stimulation was used as an index of the rate of norepinephrine washout from the myocardial interstitium. As we increased the pacing rate over the range of 90-150 min-1 in the experimental group, the mean decay half times (+/- SE) decreased by 36 +/- 4% (P less than 0.001) before desipramine and by 26 +/- 6% (P less than 0.001) in the presence of desipramine. These decrements in the decay half times were not significantly different from each other. The mean decay half times decreased by 36 +/- 4% (P less than 0.001) in the control dogs; the effects did not change appreciably from the first to the second observation period. We conclude that an increase in pacing frequency facilitates the washout of norepinephrine from the ventricular myocardium; this facilitation is equally pronounced regardless of whether the neuronal uptake mechanism is intact or suppressed.

Heart rate as a determinant of the decay rate of the cardiac inotropic response to sympathetic nervous activity

1983 ◽  
Vol 61 (11) ◽  
pp. 1374-1381 ◽  
Author(s):  
Yukitaka Masuda ◽  
Matthew N. Levy
Keyword(s):  
Heart Rate ◽  
Sinus Rhythm ◽  
Nervous Activity ◽  
Ventricular Myocardium ◽  
Sympathetic Nervous Activity ◽  
Inotropic Response ◽  
Sympathetic Stimulation ◽  
Junctional Rhythm ◽  
Decay Times ◽  
Inotropic Responses

The cardiac responses to sympathetic nerve stimulation were measured in a series of open-chest, anesthetized dogs. In half the animals, the hearts were in a sinus rhythm; in the remaining animals, the hearts were in an atrioventricular (AV) junctional rhythm. Cocaine markedly prolonged the decay times of the chronotropic responses after cessation of sympathetic stimulation, regardless of the type of rhythm. The decay times of the inotropic responses were only slightly prolonged by cocaine in animals with a sinus rhythm, but the prolongations were pronounced in animals with an AV junctional rhythm. The lower basal heart rate appeared to be more responsible for the greater decay times of the inotropic responses in the animals with an AV junctional rhythm than in those with a sinus rhythm. In a second series of dogs, complete heart block was produced, cocaine was given, AND the hearts were paced at four different frequencies. The mean decay time of the inotropic response to sympathetic stimulation varied inversely AND substantially with the pacing frequency. The change in contraction frequency probably affects the rate of neurotransmitter dissipation from the ventricular myocardium, by altering either the coronary blood flow or the massaging action of the cardiac contractions.

scholarly journals Effects of three weeks of oxygen supplementation on oxygen saturation and recovery parameters of elite wrestlers

2014 ◽  
Vol 66 (3) ◽  
pp. 1253-1260
Author(s):  
Bilal Demirhan
Keyword(s):  
Heart Rate ◽  
Oxygen Saturation ◽  
Control Group ◽  
Oxygen Supplementation ◽  
Short Term ◽  
Before And After ◽  
Fitness Parameters ◽  
The Mean ◽  
Lactate Levels ◽  
Experimental Group

The purpose of this study was to investigate the effects of three weeks of oxygen supplementation on oxygen saturation, lactate level, and heart rate (HR) responses of elite wrestlers. The subjects included fourteen elite male wrestlers, mean age of the experimental group was 19.87?0.35; the mean age of the control group was 19.62?0.51. Both groups had similar height, weight and fitness parameters. Before and after training, the heart rates, lactate levels and oxygen saturation values were recorded. Consistent with our hypothesis, the oxygen saturation (SpO2) values of the experimental group increased significantly (p<0.05) while lactate and heart rate values decreased significantly. When the pre-exercise levels of oxygen saturation were compared, the oxygen supplementation group displayed significant differences in the 2nd and 3rd weeks (P<0.05). Pre-training HR and lactate levels in the three weeks did not differ significantly. The experiment group had higher measured SpO2 values immediately after exercise in the 3rd week (P<0.05); HR and lactate levels declined after oxygen supplementation (P<0.05). Only in the 2nd and 3rd week, the HR values were lower in favor of the experimental group (P<0.05). Our findings indicate that oxygen supplementation does not have a chronic effect in increasing oxygen saturation and reducing HR and lactate values; however, oxygen saturation was found to be effective during the short-term recovery periods.

Rorschach Characteristics in Adolescents with Systemic Lupus Erythematosus

2006 ◽  
Vol 28 (1) ◽  
pp. 100-118 ◽  
Author(s):  
J. Santoantonio ◽  
L. Yazigi ◽  
E. I. Sato
Keyword(s):  
Lupus Erythematosus ◽  
Case Control Study ◽  
Activity Index ◽  
Disease Activity Index ◽  
Female Adolescents ◽  
Control Group ◽  
Intelligence Scale ◽  
The Mean ◽  
Experimental Group ◽  
Control Study

The purpose of this study was to investigate the personality characteristics in adolescents with SLE. The research design is a case-control study by means of the Rorschach Method and the Wechsler Intelligence Scale. Study group: 30 female adolescents with lupus, 12–17 years of age. The SLE Disease Activity Index was administered during the period of psychological evaluation. Control group: 32 nonpatient adolescents were matched for age, sex, and socioeconomic level. In the Wechsler Intelligence Scale the mean IQ of the experimental group was significantly lower than that of the control group (77 and 98, respectively, p < .001). In the Rorschach, the lupus patients showed greater difficulty in interpersonal interactions, although they displayed the resources to process affect and to cope with stressful situations. A positive moderate correlation (p = .069) between the activity index of the disease and the affect constriction proportion of the Rorschach was observed: the higher the SLEDAI score, the lower the capacity to process affect. There is a negative correlation between the activity index of the disease and the IQ (p = .001): with a higher activity index of the disease, less intellectual resources are available.

scholarly journals The Impact of Game-Based, Modeling, and Collaborative Learning Methods on the Achievements, Motivations, and Visual Mathematical Literacy Perceptions

SAGE Open ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 215824402110035
Author(s):  
Aziz İlhan
Keyword(s):  
Collaborative Learning ◽  
Control Group ◽  
Conventional Instruction ◽  
Game Based Learning ◽  
Mathematical Literacy ◽  
Learning Methods ◽  
Learning Groups ◽  
The Mean ◽  
The Impact ◽  
Experimental Group

The present study aimed to investigate the effects of geometry instruction activities conducted in nature based on modeling, game-based, and cooperative learning methods on achievement, mathematical motivation, and visual mathematical literacy perceptions of third-grade elementary school students. The present study is a quantitative study conducted with a pre-test/post-test experimental design with a control group. The study was conducted with 61 students (35 students in the experimental group and 26 students in the control group). Modeling-, game-, and collaborative learning-based activities were conducted with the students in the experimental group. It was determined that the achievements of students who were instructed with modeling-based activities in geometry were high when compared to that of the students instructed with collaborative learning- and game-based methods, and those in the control group where no intervention was applied. This group was followed by the game-based and collaborative learning groups. Based on the variable of motivation, the mean motivation of the students in the modeling group was higher when compared to that of the students in the collaborative learning, game-based, and conventional instruction groups. This group was followed by the collaborative and game-based learning groups. Also, based on the visual mathematical literacy perception variable, the mean visual mathematics literacy perception of the students in the collaborative learning group was higher when compared to that of the students in the groups where the modeling, game-based, and conventional instruction methods were used. This group was followed by the modeling and game-based learning groups.

Does Self-reporting Facilitate History Taking in Food Poisoning Mass-casualty Incidents?

2014 ◽  
Vol 29 (4) ◽  
pp. 417-420 ◽  
Author(s):  
Ya-I Hsu ◽  
Ying C. Huang
Keyword(s):  
Health Care ◽  
Medical History ◽  
Food Poisoning ◽  
Mass Casualty ◽  
Mass Casualty Incidents ◽  
Control Group ◽  
History Taking ◽  
Care Providers ◽  
Time Required ◽  
Experimental Group

AbstractIntroductionMedical history is an important contributor to diagnosis and patient management. In mass-casualty incidents (MCIs), health care providers are often overwhelmed by large numbers of casualties. An efficient, reliable, and affordable method of information collection is essential for effective health care response.Hypothesis/ProblemIn some MCIs, self-reporting of symptoms can decrease the time required for history taking, without sacrificing the completeness of triage information.MethodsTwo resident doctors and a number of seventh graders who had previous experience of abdominal discomfort were invited to join this study. A questionnaire was developed to collect information on common symptoms in food poisoning. Each question was scored, and enrolled students were randomly divided into two groups. The experimental group students answered the questionnaire first and then were interviewed to complete the medical history. The control group students were interviewed in the traditional way to collect medical history. Time of all interviews was measured and recorded. The time needed to complete the history taking and completeness of obtained information were compared with students’ t tests, or Mann-Whitney U tests, based on the normality of data. Comprehensibility of each question, scored by enrolled students, was reported by descriptive statistics.ResultsThere were 41 students enrolled: 22 in the experimental group and 19 in the control group. Time to complete history taking in the experimental group (163.0 seconds, SD=52.3) was shorter than that in the control group (198.7 seconds, SD=40.9) (P=.010). There was no difference in the completeness of history obtained between the experimental group and the control group (94.8%, SD=5.0 vs 94.2%, SD=6.1; P=.747). Between the two doctors, no significant difference was found in the time required for history taking (185.2 seconds, SD=42.2 vs 173.1 seconds, SD=58.6; P=.449), or the completeness of information (94.1%, SD=5.9 vs 95.0%, SD=5.0; P=.601). Most of the questions were scored “good” in comprehensibility.ConclusionSelf-reporting of symptoms can shorten the time of history taking during a food poisoning mass-casualty event without sacrificing the completeness of information.HsuY, HuangYC. Does self-reporting facilitate history taking in food poisoning mass-casualty incidents?Prehosp Disaster Med. 2014;29(4):1-4.

scholarly journals Clinical and imaging outcomes after intrathecal injection of umbilical cord tissue mesenchymal stem cells in cerebral palsy: a randomized double-blind sham-controlled clinical trial

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Man Amanat ◽  
Anahita Majmaa ◽  
Morteza Zarrabi ◽  
Masoumeh Nouri ◽  
Masood Ghahvechi Akbari ◽  
...  
Keyword(s):  
Stem Cells ◽  
Mesenchymal Stem Cells ◽  
Cerebral Palsy ◽  
Umbilical Cord ◽  
Intrathecal Injection ◽  
Control Group ◽  
Umbilical Cord Tissue ◽  
The Mean ◽  
And Control ◽  
Experimental Group

Abstract Background This study assessed the safety and efficacy of intrathecal injection of umbilical cord tissue mesenchymal stem cells (UCT-MSC) in individuals with cerebral palsy (CP). The diffusion tensor imaging (DTI) was performed to evaluate the alterations in white-matter integrity. Methods Participants (4–14 years old) with spastic CP were assigned in 1:1 ratio to receive either UCT-MSC or sham procedure. Single-dose (2 × 107) cells were administered in the experimental group. Small needle pricks to the lower back were performed in the sham-control arm. All individuals were sedated to prevent awareness. The primary endpoints were the mean changes in gross motor function measure (GMFM)-66 from baseline to 12 months after procedures. The mean changes in the modified Ashworth scale (MAS), pediatric evaluation of disability inventory (PEDI), and CP quality of life (CP-QoL) were also assessed. Secondary endpoints were the mean changes in fractional anisotropy (FA) and mean diffusivity (MD) of corticospinal tract (CST) and posterior thalamic radiation (PTR). Results There were 36 participants in each group. The mean GMFM-66 scores after 12 months of intervention were significantly higher in the UCT-MSC group compared to baseline (10.65; 95%CI 5.39, 15.91) and control (β 8.07; 95%CI 1.62, 14.52; Cohen’s d 0.92). The increase was also seen in total PEDI scores (vs baseline 8.53; 95%CI 4.98, 12.08; vs control: β 6.87; 95%CI 1.52, 12.21; Cohen’s d 0.70). The mean change in MAS scores after 12 months of cell injection reduced compared to baseline (−1.0; 95%CI −1.31, −0.69) and control (β −0.72; 95%CI −1.18, −0.26; Cohen’s d 0.76). Regarding CP-QoL, mean changes in domains including friends and family, participation in activities, and communication were higher than the control group with a large effect size. The DTI analysis in the experimental group showed that mean FA increased (CST 0.032; 95%CI 0.02, 0.03. PTR 0.024; 95%CI 0.020, 0.028) and MD decreased (CST −0.035 × 10-3; 95%CI −0.04 × 10-3, −0.02 × 10-3. PTR −0.045 × 10-3; 95%CI −0.05 × 10-3, −0.03 × 10-3); compared to baseline. The mean changes were significantly higher than the control group. Conclusions The UCT-MSC transplantation was safe and may improve the clinical and imaging outcomes. Trial registration The study was registered with ClinicalTrials.gov (NCT03795974).

Effect of Activity-Based Games on Students' Academic Achievement in Social Sciences

2021 ◽  
pp. 82-95
Keyword(s):  
Academic Achievement ◽  
Performance Test ◽  
Mean Value ◽  
Control Group ◽  
Second Phase ◽  
Initial Stage ◽  
Post Test ◽  
The Mean ◽  
Based Instruction ◽  
Experimental Group

The purpose of the research was to investigatethe effect of activity-based games on the academic achievement of graduate-level pupils in social sciences.An experimental research design with a pre-and post-test control group was used in this study. As pre-test and post-test, MCQ achievement tests containing 70 items were used as research methods for data collecting. The initial stage in this initiative was to collect data on what inspires children to learn. Both groups took a pre-test, and the results were tallied.The project's second phase was to study the effects of variousactivities on academic achievement. Both groups were given an MCQ performance test. The T-test was used to analyze the data. The findings of this study demonstrated that, compared to the control group, mostpupils'marks improved in the experimental group. The mean value showedthat experimental group participants scored 18.77on the post-test, while control group students scored 16.21. According to a post-lesson poll, most students regarded activity-based games to be more engaging than lecture-based instruction.

A STUDY ON THE EFFECTIVENESS OF USING ALPHABET CARDS GAME IN TEACHING VOCABULARY FOR COMMERCIAL BUSINESS ADMINISTRATION STUDENTS

2017 ◽  
Vol 1 ◽  
pp. 54
Author(s):  
Arita Destianingsih ◽  
Ari Satria
Keyword(s):  
Business Administration ◽  
Mean Value ◽  
T Test ◽  
Control Group ◽  
Business Administration Students ◽  
Post Test ◽  
Quasi Experimental ◽  
The Mean ◽  
Experimental Group ◽  
Administration Students

The aim of this study was to know the effectiveness of the use of alphabet cards game as interesting tool to explain vocabularies and it make it easier to remember their meanings. This study belongs to the quasi experimental research and presents pre-test, post test and to investigate the effect of using alphabet cards game on vocabulary mastery of commercial business administration students. The participants were the students from commercial business administration students at the third semester (N=54) of State Polytechnic Bengkalis and divided into two groups. Both groups were taught vocabulary, however, the experimental group students who are exposed to alphabet cards game and the controlled group students who received conventional method. Pre-test and post-test were given to both experimental group students and controlled group students. The score of the vocabulary tests were compared through independent sample t-test. The mean value of pre-test of experimental class was 61.35, while the control class was 52.23. After learning using alphabet card games in experimental class the mean value obtained in post-test was 78.85, while in control class was 59.04.  The improved of learning outcomes can be seen from the level of significance was 0.000 and it was lower than t test 0.000<0.05.  It means that the hypothesis null is not accepted. Therefore, it can be concluded that the score of the students in learning vocabulary between the experimental group and control group was significantly different. The experimental group students who learned vocabulary using alphabet cards game had increased their vocabulary mastery.

scholarly journals Investigating the Effect of Teaching Aesthetic Skills to Faculty Members on Development of Their Effective Teaching Performance1

2017 ◽  
Vol 19 (2) ◽  
pp. 90-106 ◽  
Author(s):  
Hassan Eslamian ◽  
Seyed Ebrahim Mirshah Jafari ◽  
Mohammad Reza Neyestani
Keyword(s):  
Effective Teaching ◽  
Teaching And Learning ◽  
Learning Processes ◽  
Faculty Members ◽  
Control Group ◽  
Teaching Performance ◽  
Significant Difference ◽  
Quasi Experimental ◽  
The Mean ◽  
Experimental Group

AbstractThis quasi-experimental study investigated the effect of teaching aesthetic skills to faculty members on development of their effective teaching performance through a two-group pretest-posttest design. The sample included 32 faculty members at a major Iranian university who were divided into the experimental (11 participants) and control groups (21 participants). The experimental group was taught to use aesthetic skills in the teaching and learning processes; however, no intervention was applied to the control group. To evaluate the effective teaching performance of the faculty members, a tailor-made questionnaire was used in two pretest and posttest stages, where randomly chosen students were asked to express their opinions about the faculty membersí performance. The sample size of the students was 1096 in the pretest stage and 935 in the posttest stage. Paired t-test results showed that there was no significant difference between the mean effective teaching scores of the faculty members in the control group in the pretest stage and in the posttest stage. However, the mean effective teaching scores of the faculty members in the experimental group were found to be significantly higher in the posttest. In addition, although there was no significant difference between the mean effective teaching scores of the two faculty groups in the pretest, faculty members in the experimental group outperformed their counterparts in the control group. Based on the findings, applying aesthetic skills by faculty members in the teaching and learning processes can pave the way for sustainable development of their effective teaching performance. Therefore, faculty members are recommended to acquire the required knowledge and skills to better use aesthetic skills in the teaching process.

scholarly journals PENGARUH MODEL COOPERATIVE LEARNING TIPE STUDENT TEAMS ACHIEVEMENT DIVISION TERHADAP KETERAMPILAN LAY-UP SHOOT BOLA BASKET

2020 ◽  
Vol 6 (2) ◽  
Author(s):  
Davi Sofyan
Keyword(s):  
Cooperative Learning ◽  
Sampling Technique ◽  
Control Group ◽  
Student Teams ◽  
Post Test ◽  
Quasi Experimental ◽  
The Mean ◽  
The Difference ◽  
Experimental Group ◽  
Cluster Random Sampling

The purpose of this study was to determine how much influence the cooperative learning model type student team's achievement division has on basketball shoot lay-up skills. The research method used in this research is a quasi-experimental method. The type of research design used was the non-equivalent group design. The population in this study were students of class XI SMA Negeri 1 Majalengka in 2019 totaling 424 students. The sampling technique used in this study was cluster random sampling technique. The sample in this study amounted to 214 students consisting of class XI IPS 1-4 and XI MIPA 7-8. The experimental group class XI IPS 1-2 and XI MIPA, control group class XI IPS 3-4 and XI MIPA 8. The results showed that the mean pre-test lay-up shoot of the experimental group was 4.09 while the control group was 3.92. The mean post-test shoot lay-up of the experimental group was 6.76 while the control group was 4.72. Furthermore, by looking at 95% confidence interval of the difference, there is a difference between the shoot lay-up results of the experimental group and the control group, which is -0.190 to 2.412. Thus, it can be concluded that STAD is effective in improving basketball shoot lay-up skills.

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