1. Metoprolol (ME), pindolol (PI) and propranolol (PR) were studied in nine subjects at different doses and at 'maximum beta-adrenoceptor blockade' at a defined exercise load. Exercise tests were performed after each dosing period; isoprenaline stimulation was studied at the highest dose level. 2. ME and PR reduced heart rate at rest with most doses tested, while PI had no effect on resting heart rate. 3. Exercise heart rate was reduced with the smallest daily doses (ME 75 mg; PI 7.5 mg; PR 60 mg), and maximum reduction was from 163 to 116 beats/min (ME), 124 (PT) and 115 (PR) beats/min with daily doses of 242, 23 and 233 mg, respectively. 4. Resting blood pressure was not significantly affected by any beta-adrenoceptor blocker dose, but exercise induced blood pressure decreased from 166 to 130 (ME), 138 (PI) and 131 (PR) mm Hg, respectively. 5. Mean plasma concentrations at 'maximum beta-adrenoceptor blockade' were 158 (ME), 24 (PI) and 159 (PR) ng/ml without significant differences in the plasma level variation between beta-adrenoceptor blockers. 6. Isoprenaline doses required to increase heart rate by 30 beats/min were 3.8 microgram (control), 22 microgram (ME), 458 microgram (PI) and 200 microgram (PR), respectively. The differences may be due to different ratios of beta 1, beta 2 activity of the beta-adrenoceptor blockers tested.
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http://dx.doi.org/10.1111/j.1365-2125.1980.tb01769.x | DOI Listing |
Head Neck
January 2025
Department of Medical and Surgical Sciences, Alma Mater Studiorum, University of Bologna, Bologna, Italy.
Background: Supraglottic squamous cell carcinoma (SCC) is a significant portion of head and neck cancers, with the management of clinically negative necks (cN0) through selective neck dissection (SND) being debated due to potential morbidities and low metastasis rates in levels IIb and IV.
Methods: This study is a retrospective, multicenter examination of the potential feasibility of limited neck dissection (LND), including only levels IIa and III in cN0 supraglottic SCC patients. It analyzed occult metastasis rates and explored relapse occurrences alongside potential predictors of lymph node metastasis.
Eur Heart J Digit Health
January 2025
Cardiovascular Center, Tufts Medical Center, 800 Washington Street, Boston, MA 02111, USA.
Aims: This study evaluates the performance of OpenAI's latest large language model (LLM), Chat Generative Pre-trained Transformer-4o, on the Adult Clinical Cardiology Self-Assessment Program (ACCSAP).
Methods And Results: Chat Generative Pre-trained Transformer-4o was tested on 639 ACCSAP questions, excluding 45 questions containing video clips, resulting in 594 questions for analysis. The questions included a mix of text-based and static image-based [electrocardiogram (ECG), angiogram, computed tomography (CT) scan, and echocardiogram] formats.
J Pain Res
January 2025
Department of Anesthesiology, The Second Hospital, Cheeloo College of Medicine, Shandong University, Jinan, 250033, People's Republic of China.
Background: Postoperative sore throat (POST) is a significant adverse effect after endotracheal intubation, especially with double-lumen endotracheal tubes (DLTs). Ultrasound-guided internal branch of the superior laryngeal nerve block (US-guided iSLNB) presents a potential intervention for POST. In this first randomized controlled trial to date, we aimed to investigate the effects of US-guided iSLNB, with or without perineural dexmedetomidine, on the incidence and severity of POST following DLTs.
View Article and Find Full Text PDFSurg Pract Sci
September 2023
Department of Surgery, University of KwaZulu Natal, Durban, South Africa.
Introduction: This study compares outcomes between rural and urban geriatric trauma patients at a major trauma centre in South Africa.
Materials And Methods: This retrospective cohort study from a prospectively entered data set, reviewed all patients aged 65 years or above admitted between January 2013 to December 2020 to our trauma centre at Grey's Hospital, South Africa.
Results: Over the 8-year study period, a total of 323 patients aged ≥ 65 years were included (201 males (62%), mean age: 72 years.
Front Psychol
January 2025
Department of Physical Therapy, Niigata University of Health and Welfare, Niigata, Japan.
Alexithymia is a psychological trait characterized by difficulty expressing emotions. Previous studies reported that individuals with higher alexithymia have a decreased sense of interoception, which is the sense of monitoring and controlling internal organs. Thus, we hypothesized that internal organ activity (cardiac activities in the present study) was easily affected by false feedback in individuals with severe alexithymia.
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