Influence of low extracellular Ca2+ ions on the cardiac function changes induced by verapamil in the perfused rabbit heart

1985 ◽  
Vol 63 (11) ◽  
pp. 1429-1434 ◽  
Author(s):  
Pierre A. Fortier ◽  
Gary K. Bedford ◽  
Miguel A. Chiong
Keyword(s):  
Rabbit Heart ◽  
The Other ◽  
Control Group ◽  
Enzyme Release ◽  
Control Groups ◽  
Coronary Sinus Flow ◽  
Pr Interval ◽  
Energy Stores ◽  
Group A ◽  
Sinus Flow

We tested the hypothesis that the myocardial effects of verapamil (VER) could be enhanced by decreasing the extracellular Ca2+ concentration ([Ca2+]o) in the isolated rabbit heart at 37 °C. After perfusion with standard Krebs–bicarbonate solution containing 1.27 mM Ca2+, for a 30-min period of stabilization and 15 min of control, groups of hearts were perfused for an additional 60 min with solutions containing one of the following: 1.27 mM Ca2+ (control group), 0.23 mM Ca2+ (low [Ca2+]o group), 1.27 mM Ca2+ plus 10− M VER (VER group), or 0.23 mM Ca2+ plus 10−7 M VER (combination, CBN group). These concentrations of [Ca2+]o and VER produce submaximal responses in our preparation. We found that the heart rate – LV pressure product (RPP) in the CBN group fell rapidly to 0 in the first 2–3 min of perfusion, this response being significantly lower than in the other two groups for the first 15 min. Electromechanical dissociation (EMD) appeared in one of six hearts at 60 min and in four of six hearts at 30 min in the low [Ca2+]o and VER groups, respectively, whereas it occurred in the CBN group in all hearts at 3 min. Depolarization rate (DR) fell by 10% in the low [Ca2+]o and VER groups versus a reduction of 45% in the CBN group (P < 0.05) during the last 45 min of perfusion. The PR interval increased by 300% in the CBN group, a much greater and significant change (P < 0.05) than in the hearts exposed to VER or low [Ca2+]o. The QT interval, however, increased by 50% in the low [Ca2+]o group (P < 0.05) and decreased by 20–30% in the VER and CBN groups (P < 0.05). On the other hand there were no differences in the changes in coronary sinus flow, O2 uptake, enzyme release, or energy stores among the groups. We conclude that low [Ca2+]o enhanced the effects of VER in relation only to RPP, DR, PR interval, and possibly EMD, but had no influence on metabolism.

Low extracellular Ca2+ and enzyme release in the perfused rabbit heart

1984 ◽  
Vol 62 (9) ◽  
pp. 1158-1165 ◽  
Author(s):  
Pierre A. Fortier ◽  
Gary K. Bedford ◽  
Miguel A. Chiong
Keyword(s):  
Creatine Kinase ◽  
Systolic Pressure ◽  
Rabbit Heart ◽  
Left Ventricular ◽  
Control Group ◽  
Enzyme Release ◽  
Ventricular Systolic Pressure ◽  
Coronary Sinus Flow ◽  
Perfused Rabbit Heart ◽  
Cardiac Functions

Previous studies have shown that the well-oxygenated perfused rabbit heart releases creatine kinase when treated with the calcium antagonist drug verapamil (VER) in a dose-related manner. It is possible that this effect is related to Ca2+ ion deprivation of the sarcolemma. This possibility was explored by perfusing hearts with low Ca2+ (0.5, 0.23, 0.15, and 0 mM) versus a control group (1.27 mM Ca2+) for 60 min. Low Ca2+ perfusion was associated with (i) reduction in the heart rate – left ventricular systolic pressure product and O2 consumption, (ii) tendency for the coronary sinus flow to increase, (iii) electromechanical dissociation, prolongation of atrioventricular conduction and QT interval, and (iv) decrease in myocardial glycogen. Lower total adenosine nucleotides were found only in the 0 mM Ca2+ group. As the Ca2+ concentration was reduced, the hearts lost increasing amounts of creatine kinase, aspartate aminotransferase, and lactate dehydrogenase. These results confirm the importance of Ca2+ ions in contractile and electrical cardiac functions and show that decreased availability of this cation leads to increasing enzyme leakage resembling that seen in VER-treated hearts.

scholarly journals Effect of Photofunctionalization with 6 W or 85 W UVC on the Degree of Wettability of RBM Titanium in Relation to the Irradiation Time

2021 ◽  
Vol 11 (12) ◽  
pp. 5427
Author(s):  
Arturo Sanchez-Perez ◽  
Nuria Cano-Millá ◽  
María José Moya Villaescusa ◽  
José María Montoya Carralero ◽  
Carlos Navarro Cuellar
Keyword(s):  
Light Source ◽  
Ultraviolet Light ◽  
Irradiation Time ◽  
Contact Angles ◽  
The Other ◽  
Control Group ◽  
Hydrophilic Surface ◽  
Biological Ageing ◽  
Ultraviolet C ◽  
Group A

Photoactivation with ultraviolet C light can reverse the effects derived from biological ageing by restoring a hydrophilic surface. Ten titanium discs were randomly divided into three groups: a control group, a 6 W group, and an 85 W group. A drop of double-distilled, deionized, and sterile 10 µL water was applied to each of the discs. Each disc was immediately photographed in a standardized and perpendicular manner. Measurements were taken based on the irradiation time (15, 30, 60, and 120 min). UVC irradiation improved the control values in both groups. There was no difference in its effect between the 6 W group and the other groups during the first 30 min. However, after 60 min and up to 120 min, 85 W had a significantly stronger effect. The contact angles with the 85 W ultraviolet light source at 60 and 120 min were 19.43° and 31.41°, respectively, whereas the contact angles for the 6 W UVC source were 73.8° and 61.45°. Power proved to be the most important factor, and the best hydrophilicity result was obtained with a power of 85 W for 60 min at a wavelength of 254 nm.

scholarly journals To determine how the effect of station technique on students’ achievement in astronomy subjectsAstronomi konularında istasyon tekniğinin öğrencilerin akademik başarısına nasıl etki ettiğini belirlemek

2017 ◽  
Vol 14 (4) ◽  
pp. 4561 ◽  
Author(s):  
Hamza Albayrak ◽  
Paşa Yalçın ◽  
Sema Altun Yalçın
Keyword(s):  
Quantitative Methods ◽  
T Test ◽  
The Other ◽  
Control Group ◽  
Science Lesson ◽  
Test Model ◽  
Meaningful Difference ◽  
Control Groups ◽  
Other Hand ◽  
Post Test

In this research, it was aimed to determine the effect of learning stations designed for astronomy subjects on the academic achievement of students and give an alternative method for teaching astronomy in the literature. The mixed approach in which mixed quantitative and qualitative methods were used together was preferred in the study. Among the quantitative methods, the pre-test and post-test model of the semi-experimental method was used; in addition, the protocols were applied about the method, which was used. The research was carried out with 98 seventh class students, who were under education in a secondary school located in the Eastern Anatolia Region of Turkey in the education year of 2015-2016. The quantitative data were analysed via the Astronomy Achievement Test (AAT) developed by the researchers and had 0,795 Cronbach Alpha reliability coefficient. The astronomy subjects in science lesson of the seventh class were studied with the experimental group through the learning stations; on the other hand, they were studied with the students in the control group through the activities stated in the textbook prepared by the Ministry of Education. The AAT was applied for the experimental, control groups using the pre- and post-tests, and data were analysed with the t-test. Meaningful difference was determined in AAT pre-test average scores of experimental and control groups; on the other hand, a meaningful difference was determined between the groups according to the independent samples t-test results applied with the average scores of the post-test(p<0.05). As a result of the analysis of the data gathered with the Station Observation Form (SOF), developed for the research, it was found out that the students recognise the learning stations as a technique of useful, entertaining, engaging, and easy-to-learn that enable them to learn astronomy topics effectively.Extended English abstract is in the end of Full Text PDF (TURKISH) file. ÖzetBu araştırmada, astronomi konuları için tasarlanan öğrenme istasyonlarının öğrencilerin akademik başarılarına etkisini belirlemek ve literatüre astronomi öğretimi için alternatif bir yöntem sunmak amaçlanmıştır.  Araştırmada karma nicel ve nitel yöntemlerin birlikte kullanıldığı karma yaklaşım tercih edilmiştir. Nicel yöntemlerden yarı deneysel yöntemin ön test- son test modeli kullanılmış olup ayrıca uygulanan yöntem hakkında öğrenci görüşmeleri yapılmıştır. Araştırma 2015- 2016 eğitim öğretim döneminde Doğu Anadolu Bölgesinde yer alan bir ortaokulda öğretim gören 98 yedinci sınıf öğrenci ile yürütülmüştür.  Nicel veriler için araştırmacılar tarafından geliştirilen ve cronbac’h alpha güvenlik katsayısı 0.795 olan Astronomi Başarı Testi (ABT) kullanılmıştır.  Yedinci sınıf fen bilimleri dersi içerisindeki astronomi konuları deney grubu ile öğrenme istasyonları yardımıyla, kontrol grubundaki öğrencilerle MEB’in ön gördüğü ders kitabında yer alan etkinlikler takip edilerek işlenmiştir. ABT deney ve kontrol gruplarına ön test- son test olarak uygulanarak t testi ile analiz edilmiştir. Araştırmada deney ve kontrol gruplarının ABT ön test ortalama puanları arasında anlamlı bir farklılık belirlenmişken, son test puan ortalamaları ile yapılan bağımsız örnekler t testi sonuçlarına göre gruplar arasında anlamlı bir farklılık belirlenmiştir (p<0.05). Araştırma için geliştirilen İstasyon Gözlem Formu (İGF) ile elde edilen verilerinin analizi sonucunda öğrenciler öğrenme istasyonlarını, astronomi konuları için etkili öğrenmeyi sağlayan, faydalı, eğlenceli, ilgi çekici ve kolay öğrenmeyi destekleyen bir teknik olarak gördükleri bulunmuştur.

PEG-SOD improves postischemic functional recovery and antioxidant status in blood-perfused rabbit hearts

1992 ◽  
Vol 263 (4) ◽  
pp. H1243-H1249
Author(s):  
Y. Qiu ◽  
M. Galinanes ◽  
R. Ferrari ◽  
A. Cargnoni ◽  
A. Ezrin ◽  
...  
Keyword(s):  
Redox State ◽  
Additive Group ◽  
Rabbit Heart ◽  
Left Ventricular ◽  
Control Group ◽  
Sod Activity ◽  
Group A ◽  
Group B ◽  
Developed Pressure ◽  
Postischemic Recovery

The isolated blood-perfused rabbit heart, subjected to 60 min of cardioplegic arrest and 60 min of reperfusion, was used to assess the effects of polyethylene glycol-conjugated superoxide dismutase (PEG-SOD) on postischemic recovery of left ventricular developed pressure (LVDP), the tissue activity of SOD, and tissue redox state. The five groups studied were the following: PEG-SOD-free control (group A), PEG-SOD as a pretreatment and as an additive during cardioplegia and reperfusion (group B), PEG-SOD as a pretreatment and a cardioplegic additive (group C), PEG-SOD in cardioplegia alone (group D), and PEG-SOD in reperfusion alone (group E). The results show that pretreatment with PEG-SOD improves postischemic recovery of LVDP (72 +/- 2% and 66 +/- 7 vs. 47 +/- 4% in groups B, C, and A, respectively). This protection was associated with an improved tissue redox state. Thus the ischemia-induced rise in oxidized glutathione was reduced from 313 +/- 26% (group A) to 162 +/- 15 and 138 +/- 14% (groups B and C, respectively), and the fall in reduced glutathione was attenuated from 51 +/- 5% to 35 +/- 6 and 13 +/- 5%, respectively. Tissue Mn-SOD activity was also conserved from 36 +/- 4% (group A) to 71 +/- 6 and 94 +/- 4% (groups B and C, respectively). No significant effect was seen when PEG-SOD was applied in cardioplegia or during reperfusion alone.

scholarly journals Low-dose brain estrogen prevents menopausal syndrome while maintaining the diversity of the gut microbiomes in estrogen-deficient rats

2018 ◽  
Vol 315 (1) ◽  
pp. E99-E109 ◽  
Author(s):  
Sunmin Park ◽  
Da Sol Kim ◽  
Eun Seon Kang ◽  
Da Bin Kim ◽  
Suna Kang
Keyword(s):  
Normal Control ◽  
Gut Microbiome ◽  
Positive Control ◽  
Menopausal Symptoms ◽  
The Other ◽  
Control Group ◽  
Control Groups ◽  
Ovx Rats ◽  
Control Serum ◽  
17Β Estradiol

We evaluated the effects of intracerebroventricular administration (ICV) of brain estrogen and progesterone on menopausal symptoms and their effects on the secretion of follicle-stimulating hormone(FSH) and luteinizing hormone (LH) in estrogen-deficient rats. Three weeks after ovariectomy (OVX) or sham operation, OVX rats were given ICV infusions of either 17β-estradiol (4 μg/day; ICV-E), progesterone(0.8 μg/day; ICV-P), or vehicle (control) for 4 wk. OVX rats in the positive-control group were orally provided 150 μg 17β-estradiol·kg body wt−1·day−1. Sham rats had ICV vehicle infusion (normal-control). Serum 17β-estradiol levels of ICV-E and ICV-P groups were higher than the control group but much lower than the normal- and positive-control groups. Tail skin temperature was higher in the control group than the other groups. Serum FSH and LH levels were much higher in the control group than positive- and normal-control groups, but ICV-E and ICV-P lowered the levels similar to the normal-control treatment. ICV-E and ICV-P prevented the decreased energy expenditure in OVX rats. Homeostasis model assessment estimate of insulin resistance was lowered in the descending order of the control, positive-control, ICV-P, ICV-E, and normal-control treatments. The decreased bone mineral density was prevented by the positive-control, ICV-E, and ICV-P treatments. The control group exhibited decreased short-term memory and spatial memory compared with the other groups. Surprisingly, the control group exhibited a decreased richness of the gut microbiome compared with normal-control group, and ICV-E protected against the decrease the most. In conclusion, small amounts of brain estrogen and, to some extent, progesterone improved menopausal symptoms by decreasing serum FSH levels and maintaining the diversity of the gut microbiome in estrogen-deficient rats.

Auditory brainstem evoked potentials in asymptomatic lead-exposed subjects

1986 ◽  
Vol 100 (9) ◽  
pp. 1031-1036 ◽  
Author(s):  
Y. Holdstein ◽  
H. Pratt ◽  
M. Goldsher ◽  
G. Rosen ◽  
R. Shenhav ◽  
...  
Keyword(s):  
Evoked Potentials ◽  
Auditory Brainstem ◽  
The Other ◽  
Control Group ◽  
Sensitive Detector ◽  
Control Groups ◽  
Stimulus Rate ◽  
Adults And Children ◽  
Interpeak Latency ◽  
Brainstem Evoked Potentials

AbstractAuditory Brainstem Evoked Potentials (ABEP) were recorded from 29 adults and children, accidentally exposed to lead through food until approximately a year prior to this study. ABEP were recorded in response to 75 dBHL click presented at rates of 10/sec. and 55/sec. Average values were calculated for peak latency and for interpeak latency differences. Average values of the effect of increasing stimulus rate were calculated as well. Similar values were calculated for normative child and adult control groups.IPLD (I-III) showed the most significant and recurring results, with longer intervals in lead-exposed children compared with their control group. Increasing stimulus rate, on the other hand, affected the adult lead-exposed subjects more than the children. These results may imply an impairment of the auditory system with azonal and myelin involvement. ABEP is suggested as a sensitive detector of subclinical lead exposure effects on the nervous system.

scholarly journals The Application of Story Telling in Pre – School Children Towards Language Ability

2020 ◽  
Vol 9 (1) ◽  
pp. 183-189
Author(s):  
Mamik Ratnawati ◽  
Monika Sawitri Prihatini ◽  
Heni Maryati ◽  
Ririn Probowati ◽  
Fitri Firranda Nurmalisyah ◽  
...  
Keyword(s):  
School Children ◽  
Negative Impact ◽  
Language Skills ◽  
Control Group ◽  
Test Design ◽  
Story Telling ◽  
Control Groups ◽  
Post Test ◽  
Group A ◽  
And Control

The development of children under five is very important part. Various forms of disease, malnutrition, lack of and love stimulation at this age will lead a negative impact that persists until adulthood even to old age. The purpose of this study is to determine the differences in language skills of children with the treatment of story telling methods without story telling. The method this study used quasy experiment with pre test – post test design of treatment and control group. A sample of 50 children in the Nusantara and Kasih Bunda play ground in Sudimoro Village, Megaluh, Jombang. Sampling was carried out using a simple ramdom sampling. The results of study found that treatment group had an influence of story telling on language skills in pre-school children, whereas there were no differences in story telling of language skills in the treatment and control groups.  

scholarly journals A High Protein Model Alters the Endometrial Transcriptome of Mares

Genes ◽  
2019 ◽  
Vol 10 (8) ◽  
pp. 576 ◽  
Author(s):  
Boakari ◽  
Ali ◽  
Dini ◽  
Loux ◽  
Fernandes ◽  
...  
Keyword(s):  
Ion Homeostasis ◽  
Control Group ◽  
P Value ◽  
Epithelial Tissue ◽  
Control Groups ◽  
Urea Treatment ◽  
Protein Model ◽  
Group A ◽  
Urea Group ◽  
And Control

High blood urea nitrogen (BUN) decreases fertility of several mammals; however, the mechanisms have not been investigated in mares. We developed an experimental model to elevate BUN, with urea and control treatments (7 mares/treatment), in a crossover design. Urea-treatment consisted of a loading dose of urea (0.03 g/kg of body weight (BW)) and urea injections over 6 hours (0.03 g/kg of BW/h). Control mares received the same volume of saline solution. Blood samples were collected to measure BUN. Uterine and vaginal pH were evaluated after the last intravenous infusion, then endometrial biopsies were collected for RNA-sequencing with a HiSeq 4000. Cuffdiff (2.2.1) was used to identify the differentially expressed genes (DEG) between urea and control groups (false discovery rate-adjusted p-value < 0.1). There was a significant increase in BUN and a decrease of uterine pH in the urea group compared to the control group. A total of 193 genes were DEG between the urea and control groups, with five genes identified as upstream regulators (ETV4, EGF, EHF, IRS2, and SGK1). The DEG were predicted to be related to cell pH, ion homeostasis, changes in epithelial tissue, and solute carriers. Changes in gene expression reveal alterations in endometrial function that could be associated with adverse effects on fertility of mares.

3D Animated Movies, Touch Screen Applications and Visual Motor Development of Five-Year-Old Children

2017 ◽  
Vol 9 (1) ◽  
pp. 1-9 ◽  
Author(s):  
Seçil Yücelyiğit ◽  
Neriman Aral
Keyword(s):  
Motor Skills ◽  
Motor Development ◽  
Preschool Education ◽  
The Other ◽  
Control Group ◽  
Control Groups ◽  
Interactive Applications ◽  
Visual Motor ◽  
And Control ◽  
Research Show

This study is implemented to investigate the effects of 3D animated movies and interactive applications on visual motor development of five year old children. The research has been performed in pretest-posttest-permanence test, experimental pattern with control group. For four months, every fifteen day experimental groups (24 children) watched eight episodes of 3D animated movies; 12 of them performed the interactive applications with computer while the other 12 performed the same applications with worksheets. 14 children in control group engaged merely their preschool education. Test of Visual Motor Skills-3 was used to collect and evaluate the visual motor skills of children. Since the data of the research was not distributed normally, non-parametric Kruskal Wallis, Friedman and Wilcoxon tests were used to analyze the data. The results of the research show that the visual motor skills of children who engaged the study in both test and control groups, had improved significantly.

CLEC4E as a New Tumor Marker for Early Diagnosis of GIT Tumors

2021 ◽  
pp. 3167-3172
Author(s):  
Rasha Hasan Jasim ◽  
Hadeer Haider Abdualameer
Keyword(s):  
Early Diagnosis ◽  
Tumor Marker ◽  
Patient Group ◽  
Study Groups ◽  
The Other ◽  
Control Group ◽  
Control Groups ◽  
Healthy Control ◽  
The Relationship ◽  
Sera Samples

During the period from the beginning of December 2018 to the end of May 2019, 108 resident of Babylon were included to participate in the current study, were divided into two main groups: 81 patients with GIT diseases, their age ranged from 12-80 years; and the controls group (27 individuals) with the age 17-71 years old. Furthermore, the patient group was divided into two subgroups, the first involved 51 patients with GIT tumors and the other with non-tumoral diseases of GIT (30 individuals suffered non tumoral GIT illness were enrolled as a pathological control group). CLEC4L, Serotonin were evaluated in the sera samples of the study groups. The current study revealed statistical significant increase in the levels of serotonin while it showed significant decrease in the levels of CLEC4L in the sera testers of patients with malignant GIT tumors when compared to benign GIT tumors, pathological GIT control, and healthy control groups. The present study showed that the relationship between CLEC4E with serotonin became negative. Serotonin showed the (88%) sensitivity among the assessed criteria followed by CLEC4L (76%).

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