Volume 5 Issue 1

2020-02-17 Mini Review

Angiotensin II type 1 receptor and the activation of Myosin Light-Chain Kinase and Protein Kinase C-βII: Mini Review

Summary

The involvement of the angiotensin II type 1 receptor in the Frank-Starling Law of the Heart, where the various activations are very limited, allows simple analysis of the kinase systems involved and thence extrapolation of the mechanism to that of angiotensin control of activation of cardiac and skeletal muscle contraction. The involvement of phosphorylation of the myosin light chain in the control of contraction is accepted but not fully understood. The involvement of troponin-I phosphorylation is also indicated but of unknown mechanism. There is no known signal for activation of myosin light chain kinase or Protein Kinase C-βII other than Ca2+/calmodulin but the former is constitutively active and thus has to be under control of a regulated inhibitor, the latter kinase may also be the same. Ca2+/calmodulin is not activated in Frank-Starling, i.e. there are no diastolic or systolic [Ca2+] changes. I suggest here that the regulated inhibition is by myosin light chain phosphatase and/or β-arrestin. Angiotensin activation, not involving G proteins. is by translocation of the β-arrestin from the sarcoplasm to the plasma membrane thus reducing its kinase inhibition action in the sarcoplasm. This reduced inhibition has been wrongly attributed to a mythical downstream agonist property of β-arrestin.

Abstract Read Full Article HTML DOI: 10.29328/journal.jccm.1001081 Cite this Article

2020-01-31 Research Article

Gender-specific associations of anthropometric measures of adiposity with blood pressure and hypertension in young Chinese Medical College Students

Abstract

Purpose: There are uncertainties about whether general or central obesity is the more important determinant for blood pressure and hypertension in young Chinese. We aim to investigate the association between adiposity measures and blood pressure and hypertension in young medical students.

Methods: A total of 380 medical students were recruited from the 2012 batch in the Clinical College of Dali University. Anthropometric measures and office blood pressure were measured. Blood pressure status was defined by Chinese hypertension guidelines and ACC/AHA 2017 hypertension guidelines, respectively. We examined the associations of adiposity measures (body weight, body mass index [BMI], waist circumference, hip circumference, waist-to-hip ratio [WHR], waist-to-height ratio [WHtR], ponderal index [PI], body adiposity index (BAI) and conicity index [CI]) with blood pressure and hypertension by sex.

Results: In 380 subjects (women 66.6%, mean age 21.5 years), the prevalence of obesity (BMI ≥ 28 kg/m2) was 2.1%, and the prevalence of hypertension was 2.6% (≥ 140/90 mmHg) and 24.5% (≥ 130/80 mmHg), respectively. In correlation analyses and multivariable-adjusted linear regression analyses, most adiposity measures of central obesity were significantly associated with blood pressure in men, while in women, either adiposity measures of central or general obesity were associated with blood pressure. The predictive power of adiposity measures for hypertension was generally low in men. However, adiposity measures of either general obesity or central obesity were predictive for hypertension defined by Chinese hypertension guidelines in women.

Conclusion: There are gender-specific associations of central and general obesity with blood pressure and hypertension in young Chinese medical students.

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2020-01-13 Case Report

Occluded superior vena cava and failed epicardial pacing: An unorthodox solution

Abstract

Permanent pacemaker implantation is conventionally done via upper limb veins. But in 1% - 6% cases, usual sub clavicular approach is either not possible or contraindicated due to complete occlusion of superior vena cava (SVC) or bilateral subclavian vein and/or bilateral implant site infection or thin skin [1]. Alternative approaches are warranted, including leadless pacemaker or complex lead extraction techniques, before considering surgical epicardial lead placement as a last resort because it has own hazards. We report a patient with complete heart block, total SVC obstruction, and a previously implanted malfunctioning epicardial lead presenting with pacemaker end of life. In view of exhaustion of the surgical option and in a resource constrained situation for lead extraction or leadless pacemaker, transiliac endocardial pacemaker implantation was done and a repeat surgery was averted.

Abstract Read Full Article HTML DOI: 10.29328/journal.jccm.1001079 Cite this Article

2020-01-13 Case Report

Coronary-intercostal steal syndrome, a rare connection between the left circumflex coronary artery and intercostal arteries: A case report

Abstract

A 60-year-old female patient presented with typical anginal pain on exertion and relieved by rest for about one month. Percutaneous coronary angiography was done and showed an abnormal left circumflex coronary artery connecting to intercostal artery. Embolization of that abnormal connection was done successfully and the patient discharged from hospital after 24 hours. This case shows a new form of coronary steal syndrome. This cause could be missed if not put under the differential diagnosis of typical anginal pain with normal coronary arteries.

Abstract Read Full Article HTML DOI: 10.29328/journal.jccm.1001078 Cite this Article

2020-01-09 Research Article

Effect of hemodialysis session on acute changes in inflammatory and cardiovascular risk biomarkers

Abstract

Background: Inflammation is associated with enhanced cardiovascular risk profile and increased cardiovascular mortality in end-stage kidney disease patients undergoing hemodialysis. Mechanisms of activated acute phase reaction in patients on chronic hemodialysis remain to be identified. As successful treatment of the inflammatory condition in these patients may improve long-term survival, we studied potential changes in different inflammatory biomarkers of cardiovascular risk in end-stage kidney disease patients after a mid-week hemodialysis session.

Methods: Inflammatory biomarkers of cardiovascular risk (cystatin-C, homocysteine, C-reactive protein, procalcitonin, pentraxin-3, serum amyloid-A) and atherogenic plasma lipoproteins (Lipoprotein(a), cholesterol low and high density lipoproteins) were studied in 21 end-stage kidney disease patients previously and after a mid-week hemodialysis session.

Results: We found a significant reduction in serum levels of low molecular weight molecules: cystatin-C (5.56 to 1.85 mg/L, 66.73%, p < 0.001), homocysteine (22.85 to 13.25 µmol/L, 42.01%, p < 0.001) and procalcitonin (0.788 to 0.457 ng/mL, 42.01%, p < 0.001). Large molecules as C-reactive protein (9.70 to 9.90 mg/L, 2.06%, p = 0.022) and pentraxin-3 (1.67 to 4.28 ng/mL, 156%, p < 0.001) increased, but serum amyloid-A decreased (15.90 to 12.70 mg/L, 20.13%, p < 0.05). There was no change in Lipoprotein (a) levels.

Conclusion: Pentraxin-3 was a more specific inflammatory vascular marker than C-reactive protein, and the best inflammatory marker associated with hemodialysis. Homocysteine, procalcitonin and the other small proteins could be released and removed during hemodialysis session. Further studies are needed to understand the behavior and significance of these markers after successive hemodialysis.

Abstract Read Full Article HTML DOI: 10.29328/journal.jccm.1001077 Cite this Article

2020-01-08 Review Article

A proposed mechanism to explain increases in intracranial pressure: The concept of cerebral artery wedge pressure

Abstract

We hypothesize that, with elevated cerebral spinal fluid (CSF) pressure, cerebral micro-vascular obstruction and congestion may occur despite (subdural) large-vein pressures being normal. Smaller veins emptying into these larger, dura-enveloped veins are not immune to the compressive effects of elevated CSF pressure and a “Starling Resistor” mechanism might explain why elevated CSF pressures collapse these smaller veins. This small cerebral venous starling resistor compression mechanism may be the final common pathway for many patients suffering from increased CSF pressures and might also be an important contributor to impaired focal venous drainage presenting as a headache with normal venous sinus pressures.

Abstract Read Full Article HTML DOI: 10.29328/journal.jccm.1001076 Cite this Article

Recent Articles

2020-01-09 Research Article

Effect of hemodialysis session on acute changes in inflammatory and cardiovascular risk biomarkers

Bernardo-Alio Lavin Gomez*, Maria-Teresa García Unzueta, Armando-Raul Guerra Ruiz, Sonia Perez San-Martin, Ana Berja, Natalia Fananas Rodriguez, Sara Diez Espejo and Domingo Gonzalez-Lamuno Leguina

Abstract Read Full Article HTML DOI: 10.29328/journal.jccm.1001077 Citation

2019-12-30 Research Article

Evaluation of the effect of coronary artery bypass grafting on the right ventricular function using speckle tracking echocardiography

Mahmoud Shawky Abdelmoneum, Neama Ali Elmeligy, Elsayed Abdelkhalek Eldarky and Mohamad Mahmoud Mohamad*

Abstract Read Full Article HTML DOI: 10.29328/journal.jccm.1001075 Citation

2019-11-26 Research Article

Long-Term Impact of Coronary Artery Disease in Lung Transplantation

William S Ragalie, Nilto C de Oliveira, Richard Cornwell, Keith Meyer and James D Maloney*

Abstract Read Full Article HTML DOI: 10.29328/journal.jccm.1001073 Citation