Background: Vasospasm of arterial grafts represents an unpredictable complication of coronary artery surgery and may compromise myocardial revascularization, and treatment is based on empirical therapy with nitroglycerin. Because of the potential for tolerance to nitroglycerin to occur, the authors studied different vasodilators acting through separate pathways on segments of human internal mammary artery.
Methods: Isolated vascular rings were precontracted with norepinephrine (1 microM), KCl, or the thromboxane A2 analogue (U46619, 10 nm). Nitroglycerin (a nitrovasodilator), milrinone (a type III phosphodiesterase inhibitor), papaverine (a phosphodiesterase inhibitor), prostaglandin E1, and isradipine (a dihydropyridine calcium channel blocker) were added in a cumulative fashion.
Results: The analysis of the concentration-response curves showed that vasodilators induced 90-100% relaxation of the constricted segments with norepinephrine or the thromboxane A2 analogue, except prostaglandin E1, which produced 73% relaxation at maximal concentrations. The effective concentrations of vasodilator agent that caused 50% relaxation for nitroglycerin and milrinone were within the range of the reported therapeutic concentrations in plasma. Isradipine was also effective at reversing receptor-mediated contraction (maximal relaxation=100% in internal mammary artery contracted with norepinephrine; maximal relaxation=0% in internal mammary artery contracted with the thromboxane A2 analogue).
Conclusions: Vasodilator drugs acting through multiple pathways are effective at reversing in vitro vasoconstriction.
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http://dx.doi.org/10.1097/00000542-199806000-00030 | DOI Listing |
Cureus
December 2024
Pulmonary and Critical Care, Brody School of Medicine, East Carolina University, Greenville, USA.
Lung cancer is the third most prevalent cancer, following breast cancer in women and prostate cancer in men. However, it remains the leading cause of cancer-related mortality. As treatment options have advanced, the significance of accurate diagnosis has increased, enabling targeted and more personalized therapeutic treatments.
View Article and Find Full Text PDFJ Vasc Surg Cases Innov Tech
April 2025
Division of Vascular Surgery and Endovascular Therapy, University Hospitals Harrington Heart & Vascular Institute, Case Western Reserve University, Cleveland, OH.
Renal artery (RA) anomaly is common and may have significant clinical implications. We present a case of a 29-year-old man in whom the upper two-thirds of the right kidney were supplied by the right internal mammary artery and collateral network. Additionally, the superior left RA had proximal stenosis with a distal aneurysm.
View Article and Find Full Text PDFBMJ Oncol
May 2024
Medical Oncology Department, Fondazione IRCCS Istituto Nazionale dei Tumori, Milan, Italy.
Transgender and gender-diverse (TGD) individuals face an elevated risk of cancer in comparison with the general population. This increased risk is primarily attributed to an imbalanced exposure to modifiable risk factors and a limited adherence to cancer screening programmes, stemming from historical social and economic marginalisation. Consequently, these factors contribute to poorer clinical outcomes in terms of cancer diagnosis and mortality.
View Article and Find Full Text PDFAJPM Focus
February 2025
Department of Population and Public Health Sciences, Keck School of Medicine, University of Southern California, Los Angeles, California.
Introduction: The authors determined whether certain subgroups of patients with cancer on Ohio Medicaid benefited from the program's expansion to a greater/lesser extent. Study outcomes included stage at diagnosis for screening-amenable cancers (breast [=1,707 and 2,976], cervical [=309 and 655], and colorectal [=927 and 2,009] cancer, before and after expansion, respectively) and time to treatment initiation.
Methods: Using linked data from the 2011-2017 Ohio cancer registry and Medicaid, the authors conducted a robust Poisson regression analysis for stage at diagnosis and Cox regression analysis for time to treatment initiation to obtain the adjusted risk for earlier stage at diagnosis before to after expansion or hazard of shorter time to treatment initiation for each demographic or clinical subgroup after compared with before pre-Medicaid expansion.
J Vasc Access
January 2025
Nursing Department, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China.
Background: The challenges posed by difficult intravenous access (DIVA) in clinical treatment are not only related to technical difficulties but also have the potential to affect the quality of patient care and overall experience. It is crucial to adopt effective strategies to address difficult intravenous access. Currently, the assessment of difficult veins largely relies on individual perception and experience, which introduces a significant degree of subjectivity.
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