Several recent works have shown that a brief ischemia applied during the onset of reperfusion (postconditioning) is cardioprotective in different animal models and that the early minutes of reperfusion are critical to its cardioprotection. This effect has been related to prevention of oxidative stress, but mechanisms have not been clearly demonstrated. The present study tested the hypothesis that mitochondria play a central role in peroxide production and oxidative stress during reperfusion and are responsible for the protective effect of postconditioning. Isolated perfused rat hearts were subjected to complete global ischemia for 45 min and reperfused for 40 min. Normoxic group was reperfused with a Krebs-Henseleit solution with the preischemic pO2 level (600 mmHg); in the "hypoxic group," normoxic reperfusion was preceded by 3 min with 150 mmHg pO2. Reperfusion was stopped at 3 and 40 min. The rate of hydroperoxide production, GSH, GSSG, and carbonyl protein levels were measured in mitochondria at 3 min and at the end of reperfusion. GSH and GSSG were also measured in tissue. Hemodinamic function was monitored during the experiment. LVEDp increased and LVDp decreased in the normoxic group but not in the hypoxic group. The rate of mitochondrial peroxide production was higher in normoxic than in the hypoxic group 3 min after reperfusion and at its conclusion. Accordingly, GSH was oxidized in normoxic but not in hypoxic hearts. Mitochondria carbonyl proteins were significantly higher in normoxic than in the hypoxic group at the end of reperfusion. In this model, 1) hypoxic reperfusion at the onset of reperfusion reduces myocardial injury; 2) the major rate of mitochondrial peroxide production is 3 min after the onset of reperfusion; 3) cardioprotection of postconditioning correlates with reduced mitochondria peroxide production and prevention of GSH oxidation.
Background: Various microorganisms such as bacteria, virus, and fungi can infect humans and cause not just a simple infection but septic conditions, organ dysfunction, and precancerous conditions or cancer involving various organ systems. After the discovery of the microscope, it was easier to discover and study such microorganisms, as in the case of Helicobacter pylori, a pathogen that was seen in the distant era of the nineteenth century but without being recognized as such. It took 100 years to later discover the pathogenesis and the cancer that this bacterium can cause. Since it was discovered, until today, there has been a continuous search for the understanding of its pathogenetic mechanisms, and the therapeutic approach is continuously updated. Methods: We investigated how diagnosis and therapy were dealt with in the past and how researchers sought to understand, exactly, the pathogenetic biomolecular mechanisms of H. pylori, from the genesis of the infection to the current knowledge, with an analysis of carcinogenic mechanisms in the stomach. We have examined the scientific evolution of the knowledge of the disease over these 40 years in the gastroenterological and pharmacological fields. This was possible through a search in the databases of Medline, the WHO website, the Centers for Disease Control and Prevention (CDC) website, PubMed, and Web of Science to analyze the earlier and the latest data regarding H. pylori. Results: With the scientific discoveries over time, thanks to an increasing number of progressions in scientific research in the analysis of the gastric mucosa, the role of Helicobacter pylori in peptic ulcer, carcinogenesis, and in some forms of gastric lymphoma was revealed. Furthermore, over the years, the biomolecular mechanism involvement in some diseases has also been noted (such as cardiovascular ones), which could affect patients positive for H. pylori. Conclusions: Thanks to scientific and technological advances, the role of the bacterium H. pylori in carcinogenesis has been discovered and demonstrated, and new prospective research is currently attempting to investigate the role of other factors in the stomach and other organs. Cancer from H. pylori infection had a high incidence rate compared to various types of cancer, but in recent years, it is improving thanks to the techniques developed in the detection of the bacterium and the evolution of therapies. Thus, although it has become an increasingly treatable disease, there is still continuous ongoing research in the field of treatment for resistance and pharma compliance. Furthermore, in this field, probiotic therapy is considered a valid adjuvant.
Reactive oxygen species (ROS) are considered an important factor in ischemia/reperfusion injury to cardiac myocites. Mitochondrial respiration is an important source of ROS generation and hence a potential contributor to cardiac reperfusion injury. Appropriate treatment strategy could be particularly useful to limit this ROS generation and associated mitochondrial dysfunction. In the present study, we examined the effect of lowering the oxygen tension, at the onset of the reperfusion, on various parameters of mitochondrial bioenergetics in rat heart tissue. After isolation of mitochondria from control, ischemic, normoxic and hypoxic reperfused rat heart, various bioenergetic parameters were evaluated such as rates of mitochondrial oxygen consumption, complex I and complex III activity, H2O2 production and in addition, the degree of lipid peroxidation, cardiolipin content and cardiolipin oxidation. We found that normoxic reperfusion significantly altered all these mitochondrial parameters, while hypoxic reperfusion had a protective effect attenuating these alterations. This effect appears to be due, at least in part, to a reduction of mitochondrial ROS generation with subsequent preservation of cardiolipin integrity, protection of mitochondrial function and improvement of post-ischemic hemodynamic function of the heart.
Background-The aim of this retrospective study is to investigate efficacy and middle-term results of the stent graft treatment for diseases of descending thoracic aorta. No stent graft-related complications were detected, although only in 1 case, an asymptomatic rupture of the Excluder connecting bar was found with a perforation of the fabric and an intra-aortic exposition of the bar itself. In 2 patients with chronic dissection an asymptomatic type II endoleak was detected. A total of 4 hospital deaths resulted in an overall operative mortality of 3.9%. Seven patients (6.3%) died during the follow-up 5 of them for other diseases (4.5%). However, a 40.9% mortality was observed within the obliged medical treatment group. Conclusions-Endovascular treatment of thoracic aortic diseases, even in the acute phase, may represent a valid option with a low mortality rate. Moreover, the efficacy is proved in the middle-term whereas the long-term follow-up is still pending. Methods and Results-From
In the area of Emergency Room (ER), many patients present criteria compatible with a SIRS, but only some of them have an associated infection. The new definition of sepsis by the European Society of Intensive Care Medicine and the Society of Critical Care Medicine (2016), revolutionizes precedent criteria, overcoming the concept of SIRS and clearly distinguishing the infection with the patient’s physiological response from the symptoms of sepsis. Another fundamental change concerns the recognition method: The use of SOFA (Sequential-Sepsis Related-Organ Failure Assessment Score) as reference score for organ damage assessment. Also, the use of the qSOFA is based on the use of three objective parameters: Altered level of consciousness (GCS <15 or AVPU), systolic blood pressure ≤ 100 mmHg, and respiratory rate ≥ 22/min. If patients have at least two of these altered parameters in association with an infection, then there is the suspicion of sepsis. In these patients the risk of death is higher, and it is necessary to implement the appropriate management protocols, indeed the hospital mortality rate of these patients exceeds 40%. Patients with septic shock can be identified by the association of the clinical symptoms of sepsis with persistent hypotension, which requires vasopressors to maintain a MAP of 65 mmHg, and serum lactate levels >18 mg/dL in despite of an adequate volume resuscitation. Then, patient first management is mainly based on: (1) Recognition of the potentially septic patient (sepsis protocol-qSOFA); (2) Laboratory investigations; (3) Empirical antibiotic therapy in patients with sepsis and septic shock. With this in mind, the authors discuss the most important aspects of the sepsis in both adults and infants, and also consider the possible treatment according current guidelines. In addition, the possible role of some nutraceuticals as supportive therapy in septic patient is also discussed.
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