Ischemic conditioning of human heart muscle depends on opioid-receptor system.

BACKGROUND: Despite progress in the invasive treatment of ischemic heart disease, the ability to limit ischemia-reperfusion (I/R) injury remains largely unrealized. Ischemic pre-conditioning (IPC) and post-conditioning (POC) induce the protective mechanisms of resistance against I/R injury. Stimulation of opioid receptors mimic the protective effect of IPC or POC in an animal models. We tested the hypothesis, that IPC and POC provide cardioprotection in opioid-dependent mechanism in human myocardium. METHODS: Human atrial trabeculae were subjected to I/R injury. To achieve IPC, single hypoxia period preceded the applied lethal hypoxia, to achieve POC triple hypoxia periods followed lethal hypoxia. Naloxone was used at the onset of lethal hypoxia in IPC protocol, and at the time of re-oxygenation in POC protocol. Contractive function of the myocardium was assessed as maximal force of contraction (Amax), rate of rise of force of contraction (+dV/dT) and diastolic parameter - rate of decay of force of contraction (-dV/dT). RESULTS: Co-application of naloxone with IPC or POC resulted in decrease of Amax, +dV/dT and -dV/dT during re-oxygenation period as compared to IPC or POC only. CONCLUSIONS: Naloxone abrogates beneficial effect of IPC and POC. IPC and POC in humans provide cardioprotection in opioid receptor system dependent mechanism.

Job satisfaction and social identification among paramedics in southern Poland.

Introduction: Job satisfaction, based on professional and non-professional factors and individual characteristics of employees, is an important element influencing both the quality of care provided and employee turnover. Material and method: The study included 137 paramedics employed in field teams and hospital emergency departments. The Job Satisfaction Scale (SSP), the Minnesota Job Satisfaction Questionnaire (MSQ), the Utrecht Work Engagement Scale (UWES), and the Three Dimensional Strength of Group Identification Scale (TSIG) were used to collect the data. Results: The average job satisfaction score measured with SSP in the studied group of paramedics was 24.50 and the average job satisfaction score measured with MSQ was 74.16. The average value of the group identification in the study sample was 61.15. Of the three subscales, the highest scores were obtained in the affect toward the group subscale -22.44, and the lowest in the cognitive centrality subscale -18.78. The analysis showed that job satisfaction positively correlated with social identification (r = 0.43) and the ingroup ties (r = 0.43), cognitive centrality (r = 0.34) and ingroup affect (r = 0.37). Conclusions: The studied group of paramedics showed moderate job satisfaction (measured with SSP) and work engagement, with a simultaneous high level of job satisfaction (measured with MSQ) and social identification with the professional group. Social identification of studied paramedics varied depending on gender. Women showed higher levels of cognitive centrality, which might mean that they might have had greater need to categorize themselves as paramedics.

Assessment of the Severity of COVID-19 on the Basis of Examination and Laboratory Diagnostics in Relation to Computed Tomography Imagery of Patients Hospitalised Due to COVID-19-Single-Centre Study.

From the moment the SARS-CoV-2 virus was identified in December 2019, the COVID-19 disease spread around the world, causing an increase in hospitalisations and deaths. From the beginning of the pandemic, scientists tried to determine the major cause that led to patient deaths. In this paper, the background to creating a research model was diagnostic problems related to early assessment of the degree of damage to the lungs in patients with COVID-19. The study group comprised patients hospitalised in one of the temporary COVID hospitals. Patients admitted to the hospital had confirmed infection with SARS-CoV-2. At the moment of admittance, arterial blood was taken and the relevant parameters noted. The results of physical examinations, the use of oxygen therapy and later test results were compared with the condition of the patients in later computed tomography images and descriptions. The point of reference for determining the severity of the patient's condition in the computer imagery was set for a mild condition as consisting of a percentage of total lung parenchyma surface area affected no greater than 30%, an average condition of between 30% and 70%, and a severe condition as greater than 70% of the lung parenchyma surface area affected. Patients in a mild clinical condition most frequently had mild lung damage on the CT image, similarly to patients in an average clinical condition. Patients in a serious clinical condition most often had average levels of damage on the CT image. On the basis of the collected data, it can be said that at the moment of admittance, BNP, PE and HCO3- levels, selected due to the form of lung damage, on computed tomography differed from one another in a statistically significant manner (p < 0.05). Patients can qualify for an appropriate group according to the severity of COVID-19 on the basis of a physical examination and applied oxygen therapy. Patients can qualify for an appropriate group according to the severity of COVID-19 on the basis of BNP, HCO3 and BE parameters obtained from arterial blood.

Opioidergic conditioning of the human heart muscle in nitric oxide-dependent mechanism.

BACKGROUND: Opioidergic conditioning is well documented to trigger cardioprotection against ischemia/ reperfusion (I/R) injury. Previous studies on animal models have suggested that nitric oxide (NO) mediates the beneficial effect of opioids, but the role of NO in humans seems to be controversial. OBJECTIVES: The aim of the study was to assess the influence of NO modulators on opioid-induced cardioprotection in the human myocardium. MATERIAL AND METHODS: Trabeculae of the human right atria were electrically driven in an organ bath and subjected to simulated I/R injury. The non-selective inhibitor of nitric oxide synthase (NOS) - N-methyl-l-arginine (LNMMA), the donor of NO - S-Nitroso-N-acetylpenicillamine (SNAP) or morphine (in the amount of 10-4 M) were used at the time of re-oxygenation. The additional trabecula was subjected to the hypoxia protocol only (control). The contractility of the myocardium was assessed as the maximal force of a contraction (Amax), the rate of rise of the force of a contraction (Slope L) and the cardiac muscle relaxation - as the rate of decay of the force of a contraction (Slope T). RESULTS: The application of 100 µM LNMMA resulted in the decrease of Amax, Slope L and Slope T during the re-oxygenation period as compared to control. The application of 10-4 M morphine and/or 100 µM SNAP resulted in a partial reversal of the detrimental influence of LNMMA. CONCLUSIONS: At the re-oxygenation period, the blockade of NO synthesis has a deleterious effect on the systolic and diastolic function of the human myocardium as well as attenuates the beneficial effect of morphine conditioning.