34 research outputs found

    Langendorff’s isolated perfused rat heart technique: a review

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    The Langendorff’s isolated perfused small mammalian heart represents the optimal compromise in the conflict between the quantity and quality of data that can be acquired from an experimental model versus its clinical relevance, especially in relation to ischemia-reperfusion injury. We analyzed the important recent, as well as standard older articles to highlight the importance of Langendorff’s isolated heart technique using the rat as an experimental animal model. The retrograde perfusion of isolated rat heart preparation is the most commonly used technique in cardiovascular research experiments with many advantages. The longevity of this preparation is one of the main advantages. From the moment an ex vivo preparation is established, it starts to deteriorate and the rate will depend on number of factors such as the skill of the operator, the species of animal, age, initial heart rate, choice and composition of the perfusion fluid, flow rate, presence or absence of various drugs, preload pressure, and the temperature at which the studies are carried out. Recently, various techniques and variables measured have undergone modifications. This review article has attempted to address many of the issues, developments, and applications which will assist investigators to make the best possible use of this experimental model using the rat

    Fingolimod plays role in attenuation of myocardial injury related to experimental model of cardiac arrest and extracorporeal life support resuscitation

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    Background: Sudden cardiac arrest is a major global health concern, and survival of patients with ischemia-reperfusion injury is a leading cause of myocardial dysfunction. The mechanism of this phenomenon is not well understood because of the complex pathophysiological nature of the disease. Aim of the study was to investigate the cardioprotective role of fingolimod in an in vivo model of cardiac arrest and resuscitation.Methods: In this study, an in vivo rat model of cardiac arrest using extracorporeal membrane oxygenation resuscitation monitored by invasive hemodynamic measurement was developed. At the beginning of extracorporeal life support (ECLS), animals were randomly treated with fingolimod (Group A, n = 30) or saline (Group B, n = 30). Half of the animals in each group (Group A1 and B1, n = 15 each) were sacrificed after 1 h, and the remaining animals (Group A2 and B2) after 24 h of reperfusion. Blood and myocardial tissues were collected for analysis of cardiac features, inflammatory biomarkers, and cell signaling pathways.Results: Treatment with fingolimod resulted in activation of survival pathways resulting into reduced inflammation, myocardial oxidative stress and apoptosis of cardiomyocytes. This led to significant improvement in systolic and diastolic functions of the left ventricle and improved contractility index.Conclusions: Sphingosine1phosphate receptor activation with fingolimod improved cardiac function after cardiac arrest supported with ECLS. Present study findings strongly support a cardioprotective role of fingolimod through sphingosine-1-phosphate receptor activation during reperfusion after circulatory arrest

    Refurbishment of public housing villas in the United Arab Emirates (UAE): energy and economic impact

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    © 2016, Springer Science+Business Media Dordrecht. This study aims at assessing the technical and economic benefits of refurbishing existing public housing villas in the UAE. Four representative federal public housing villas built between 1980s and 2010s were modeled and analyzed. The Integrated Environmental Solutions-Virtual Environment (IES-VE) energy modeling software was used to estimate the energy consumption and savings due to different refurbishment configurations applied to the villas. The refurbishment technical configurations were based on the UAE’s Estidama green buildings sustainability assessment system. The refurbishment configurations include upgrading three elements: the wall and roof insulation as well as replacing the glazing. The annual electricity savings results indicated that the most cost-efficient refurbishment strategy is upgrading of wall insulation (savings up to 20.8 %) followed by upgrading the roof’s insulation (savings up to 11.6 %) and lastly replacing the glazing (savings up to 3.2 %). When all three elements were refurbished simultaneously, savings up to 36.7 % were achieved (villa model 670). The savings translated to CO2 emission reduction of 22.6 t/year. The simple and discounted payback periods for the different configurations tested ranged between 8 and 28 and 10 and 50 years, respectively

    Identification of phytoconstituents from Albizia lebbeck as potential therapeutics against HIV-1 reverse transcriptase associated with infective endocarditis: In silico and in vitro approaches

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    Acquired immune deficiency syndrome (AIDS) is an unadorned disease affected via the human immunodeficiency virus (HIV), which has become the most infectious diseases worldwide. HIV-1 RT has been shown to be present in the cardiac tissue of patients with HIV-associated infective endocarditis, and to be associated with the development of valvular lesions and other cardiac abnormalities. The use of anti-retroviral therapies has helped to control the virus and reduce the incidence of HIV-1 associated infective endocarditis. Though, these treatments have several adjacent effects, and the improvement of drug-resistant stresses of the virus has become a significant challenge in HIV treatment. This study is to identify A. lebbeck phytoconstituents with HIV-1 RT inhibitory activity for potential therapeutic use against HIV-1 RT associated with infective endocarditis. We performed in silico and in vitro screening of natural cardiovascular phytoconstituents from Albizia lebbeck, a medicinal plant that has been traditionally used for the management of numerous diseases. The in silico results showed that all three compounds (geraldone, luteolin, and isookanin) exhibited affinities of solid binidng to the active amino acids of HIV-1 RT's DNA-polymerase (DNA-p) and Ribonuclease-H (RNA-H) active positions, suggesting their potential as HIV-1 RT inhibitors. In vitro assessment of the three compounds at a concentration of 1 mg/mL revealed that Geraldone exhibited the most effective inhibitory consequence on HIV-1 RT activity (83.45%), followed by Isookanin (75.88%) and Luteolin (66.36%). These findings suggest that these compounds have the potential to inhibit HIV-1 RT associated with infective endocarditis and could assist as main compounds for emerging unique anti-HIV-1 agents. Further studies are needed to confirm the in vitro and in vivo efficacy of these molecules and assess their safety and efficiency as anti-HIV-1 drugs

    Anti-inflammatory effect of anthocyanin-rich extract from banana bract on lipopolysaccharide-stimulated RAW 264.7 macrophages

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    Banana is an important fruit crop in the World and produced at large. Banana bract is the rich source of anthocyanin however, its biological activity is least explored. In the present study, anthocyanin-rich extract from banana bract (BBA) was prepared and characterized for the presence of various phytoconstituents using liquid chromatography/electrospray ionization tandem mass spectrometry (LC-ESI/MS/MS). Anti-inflammatory property of BBA in lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophage-like cells was studied. LC-ESI/MS/MS analysis identified the presence of various phenolics compounds, flavonoids and anthocyanin in BBA. BBA showed in vitro antioxidant activity. LPS stimulation decreased the cell viability whereas BBA treatment preserved the macrophage cell viability against LPS. BBA suppressed the LPS-stimulated NO, pro-inflammatory and PGE2 production in RAW 264.7 cells. BBA increased the endogenous antioxidants level against LPS-stimulation. BBA inhibited the nuclear translocation of NF-κB under LPS-stimulated conditions. Altogether, the phytoconstituents present in BBA would have acted synergistically to bring anti-inflammatory activity

    Agmatine induces gastric protection against ischemic injury by reducing vascular permeability in rats

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    AIM: To investigate the effect of administration of agmatine (AGM) on gastric protection against ischemia reperfusion (I/R) injury

    Effect of Acute Myocardial Infarction on a Disintegrin and Metalloprotease with Thrombospondin Motif 13 and Von Willebrand Factor and Their Relationship with Markers of Inflammation

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    Objectives. Coagulation mechanisms and fibrinolytic assembly are important components role players of acute myocardial infarction (AMI) progression. Our study objective was to see the serial variations in the levels of Von Willebrand factor (VWF) and A Disintegrin and Metalloprotease with ThromboSpondin motif (ADAMTS13) over the course of AMI and to determine their relationship with the cardiovascular risk markers and the patient’s clinical characteristics. Methods. This project was done at the departments of Emergency Medicine, Physiology and Cardiac sciences of King Saud University Medical City. We studied ADAMTS13, VWF, fibrinogen, and CRP levels in 80 patients with AMI when patients were admitted; post AMI by 3-4 days and at follow-up of 3 months. We compared them with a control group consisting of 36 subjects. Results. AMI had significantly lower levels of ADAMTS13 at AMI and after 3-4 days; at follow-up the difference in levels was nonsignificant, when compared with controls. Similarly, VWF levels were significantly higher in AMI and remained high even at follow-up compared to control subjects. VWF/ADAMTS13 ratio was also significantly higher at AMI and 3-4 days while at follow-up difference was nonsignificant compared to control subjects. Regression analysis between hsCRP and ADAMTS13 showed an inverse relationship (r=0.376,p<0.01), while correlation with VWF was significantly positive (r=0.337,p<0.01). Conclusions. Increased levels of VWF and reduced levels of ADAMTS13 activity may contribute to the pathogenesis of acute myocardial infarction and might prove to be important mediators of AMI progression

    Impact of GDP, spending on R&D, the number of universities and scientific journals on research publications in environmental sciences in the Middle East

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    Objectives: This study aimed to assess the impact of the Gross Domestic Product (GDP), spending on Research and Development (R&D), the number of universities and scientific journals on the published research documents, citable documents, citations per document and H-index in environmental sciences in the Middle East countries. Materials and Methods: All the 16 Middle East countries were included in the study. Information regarding the GDP, spending on R&D, the total number of universities and indexed journals was collected. Total number of research documents (papers), citable documents, citations per document and H-index in environmental sciences during the period 1996-2011 was recorded. The study used the World Bank, SCI-mago/Scopus, Web of Science, Journal Citation Reports (Thomson Reuters) as the main sources of information. Results: The mean GDP per capita of all the Middle East countries amounted to 18 125.49±5386.28 US, spending on R&D was 0.63±0.28 US, the number of universities equaled 36.56±11.33 and mean ISI indexed journals amounted to 8.25±3.93. The mean number of research documents published in environmental sciences in the Middle East countries during the period 1996-2011 was 2202.12±883.98; citable documents: 2156.87±865.09; citations per document: 8.74±0.73; and the H-index: 35.37±6.17. There was a positive correlation between the money spent on R&D and citations per documents (r = 0.6, p = 0.01), H-Index (r = 0.6, p = 0.01); the number of universities and a total of research documents (r = 0.65, p = 0.006), citable documents (r = 0.65, p = 0.006), H-Index (r = 0.50, p = 0.04), as well as ISI indexed journals and total research documents (r = 0.94, p = 0.0001), citable documents (r = 0.94, p = 0.0001), H-Index (r = 0.73, p = 0.001). Conclusions: The Middle East countries which spend more on R&D and which have a large number of universities and ISI indexed journals are likely to produce more significant volume of research papers in the field of environmental science

    Comparison of Biological, Pharmacological Characteristics, Indications, Contraindications and Adverse Effects of JYNNEOS and ACAM2000 Monkeypox Vaccines

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    Human monkeypox is an emerging viral zoonotic disease, that has caused highly distinctive, challenging and threatening problems worldwide. The US Food and Drug Administration (FDA) has given interim authorization for the JYNNEOS and ACAM2000 vaccines for the outbreak of monkeypox 2022. The present study aims to highlight the globally derived evidence about the biological and pharmacological features, indications, contraindications and adverse effects of JYNNEOS and ACAM2000 vaccines. Initially, 82 documents were selected and, finally, 14 fact sheets, documents and international organizations were included. The data were recorded from the World Health Organization (WHO), Centers for Disease Control and Prevention (CDC), Food and Drug Administration (FDA) USA, ISI-Web of Science, PubMed, EMBASE and Scopus. The data revealed that the JYNNEOS vaccine has been recommended to children, adults, females during pregnancy and people of all age groups with a dose of 0.5 mL, and the complete vaccination cost per person is about USD 115. It provides immunogenicity, and the mean titer of neutralizing antibodies was 153.5. However, the ACAM2000 vaccine is contraindicated in infants and pregnant females, and recommended to people over 18 years of age and older, with a single dose of 0.0025 mL, and a cost of about USD 139. ACAM2000 provides immunogenicity, and the mean titer of neutralizing antibodies was 79.3. The JYNNEOS vaccine has mild adverse effects including pain, redness, swelling or itching at the site of the vaccine shot, fever, fatigue, headache, nausea and muscle pain. However, the ACAM2000 vaccine can cause pain, redness, edema, headache, fever, fatigue, muscle pain, body ache, nausea, vomiting, diarrhea, shortness of breath and increased risk of myopericarditis and cardiomyopathy. The evidence supports the view that both vaccines are beneficial, but the overall impact of JYNNEOS is better than that of ACAM2000
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