14 research outputs found
Recent Advances of Transition Metal Complexes for Photopolymerization and 3D Printing under Visible Light
The possibility of exploiting visible light to induce polymerizations is extremely appealing from a technological point of view as it improves the sustainability of the overall process. To achieve this objective, it is necessary to employ single- or multicomponent systems containing a photoinitiator, and in some cases, a photosensitizer in combination. Due to their long-lived excited states and reversible redox properties, transition metal complexes are a valid choice to be applied in photoinitiating systems, often exhibiting enhanced conversions compared to purely organic compounds. This review presents an overview of the transition metal complexes exploited in photopolymerization reactions. Particular attention will be devoted to recent applications in 3D printing, highlighting the possible challenges that need to be faced to achieve highly efficient and more sustainable processes
Gastric Necrosis and Perforation Following Massive Gastric Dilatation in an Adolescent Girl: A Rare Cause of Acute Abdomen.
Gastric necrosis with perforation is a rare and potentially life-threatening condition in childhood beyond the neonatal period. We report a case of gastric necrosis and perforation of a portion of the great curvature due to a massive gastric dilatation caused by pathological aerophagia in a 13-years-old, mentally impaired adolescent girl. Despite the successful surgical treatment, the patient's condition rapidly deteriorated post-operatively and she died due to the multisystem organ failure and multiple infections. In addition, we surveyed the literature on this rare condition and assessed the preventive actions to reduce this life-treating condition
The effects of valsartan on cardiac function and pro-oxidative parameters in the streptozotocin-induced diabetic rat heart
© 2020, University of Kragujevac, Faculty of Science. All rights reserved. Diabetes mellitus is a major risk factor for cardiovascular diseases, while cardiovascular diseases are a leading cause of morbidity and mortality worldwide. The renin–angiotensin– aldosterone system controls renal, cardiovascular, adrenal function and regulates fluid and electrolyte balance as well as blood pressure. Because of his role, inhibition of renin-angiotensin-aldosteron system is another therapy approach that reduces the risk of diabetes and cardiovascular disease. In this study, our goal was to evaluate effect of valsartan,as inhibitor of angiotensin II receptor type 1, on cardiac tissue and function, with focus on cardiodynamic and oxidative stress. The present study was carried out on 20 adult male Wistar albino rats (8 week old and with body masses of 180-200 g). Rats were divided randomly into 2 groups (10 animals per group). Healthy animals treated with 1 μM of valsartan and streptozotocin-induced diabetic animals perfused with 1 μM of valsartan 4 weeks after the induction of diabetes. Our results demonstrated that acute application of valsartan has different effect on cardiodynamics in rat heart of diabetic and healthy animals but did not improve cardiac function in hy-perglycemia-induced changes. A challenge for further investi-gations are studies with chronic or acute administration, alone or in combination with other angiotensin-converting-enzyme inhibitor in various models of diabetes
Search for Alternative Two‐Step‐Absorption Photoinitiators for 3D Laser Nanoprinting
Recent studies have opened the door to a new generation of photoinitiators for 3D laser nanoprinting. Therein, the simultaneous absorption of two photons, commonly referred to as two-photon absorption, is replaced by the sequential absorption of two photons in two consecutive one-photon absorption processes. This process has been termed two-step absorption. Importantly, two-step absorption can be accomplished by inexpensive compact low-power continuous-wave blue laser diodes instead of femtosecond laser systems in the red spectral region. Red-shifting the second absorption step with respect to the first one results in an and-type optical nonlinearity based on two-color two-step absorption. Herein, alternatives are systematically explored to the few already reported one- and two-color two-step-absorption photoinitiators, including the search for photoinitiators that can be excited by one-color two-step absorption and be de-excited by a disparate laser color.</p
Analysis of clinical, haematological and biochemical parameters in patients with infectious mononucleosis
© 2015, University of Kragujevac, Faculty of Science. All rights reserved. Primary infection with Epstein-Barr virus (EBV) usually occurs in early childhood and often does not present clinical symptoms. More than 90% of adults are infected with this virus. A primary infection that occurs in adolescence or adulthood is usually clinically presented as infectious mononucleosis with a triad of symptoms: fever, lymphadenopathy and pharyngitis. Our retrospective study included 51 patients with a median age of 17 (9-23) years and serologically confirmed infectious mononucleosis. All patients with infectious mononucleosis were treated at the Clinic for Infectious Diseases at the Clinical Center in Kragujevac during 2013. We analysed the clinical, haematological and laboratory parameters of patients. The aspartate-aminotransferase levels were increased in 40 patients, with a mean value of 116.24 (±93.22); the alanine-aminotransferase levels were increased in 44 patients, with a mean value of 189.24 (±196.69). Lymphadenopathy was the most common clinical feature upon admission in 49 patients (96%); 38 patients (74.5%) had splenomegaly, and 20 (39%) had hepatomegaly. Twenty-six patients (51%) had leukocytosis with lymphocytosis, while 15 (75%) of the 20 who had a normal leukocyte count also had lymphocytosis. In the present study, we updated the clinical, haematological and laboratory parameters, which may lead to the establishment of an accurate diagnosis and promote further treatment of the patients
Analysis Of Clinical, Haematological And Biochemical Parameters In Patients With Infectious Mononucleosis
Primary infection with Epstein-Barr virus (EBV) usually occurs in early childhood and often does not present clinical symptoms. More than 90% of adults are infected with this virus. A primary infection that occurs in adolescence or adulthood is usually clinically presented as infectious mononucleosis with a triad of symptoms: fever, lymphadenopathy and pharyngitis. Our retrospective study included 51 patients with a median age of 17 (9-23) years and serologically confirmed infectious mononucleosis. All patients with infectious mononucleosis were treated at the Clinic for Infectious Diseases at the Clinical Center in Kragujevac during 2013. We analysed the clinical, haematological and laboratory parameters of patients. The aspartate-aminotransferase levels were increased in 40 patients, with a mean value of 116.24 (±93.22); the alanine-aminotransferase levels were increased in 44 patients, with a mean value of 189.24 (±196.69). Lymphadenopathy was the most common clinical feature upon admission in 49 patients (96%); 38 patients (74.5%) had splenomegaly, and 20 (39%) had hepatomegaly. Twenty-six patients (51%) had leukocytosis with lymphocytosis, while 15 (75%) of the 20 who had a normal leukocyte count also had lymphocytosis. In the present study, we updated the clinical, haematological and laboratory parameters, which may lead to the establishment of an accurate diagnosis and promote further treatment of the patients
Assessment of hemostatic disturbances in women with established rheumatoid arthritis
© 2019, The Author(s). Objectives: This study was aimed to assess hemostatic disturbances in female patients with established rheumatoid arthritis (RA) in relation to menopausal status and disease activity. Method: Ninety women were included in the study, 42 patients and 48 age-matched healthy controls. There were no differences between the investigated groups regarding the presence of traditional cardiovascular risk factors. Two global hemostatic assays were employed, namely endogenous thrombin potential (ETP) and overall hemostasis potential (OHP). The parameters of the ETP assay (ETP, C-max, t-lag, t-max) and OHP assay (overall coagulation potential (OCP) and overall fibrinolytic potential (OFP)) were assessed. Moreover, the parameters of the fibrin clot (lag time, Max Abs, and slope) were measured by clot turbidity and scanning electron microscopy (SEM). Both patients and controls were divided into four subgroups according to menopause status. Results: The premenopausal controls differed significantly from all other subgroups in terms of diminished levels of ETP (p = 0.02), C-max (p = 0.01), OCP (p = 0.02), OHP (p = 0.001), and Max Abs (p = 0.008), while OFP (p = 0.0001) was increased. This tendency was not seen in the premenopausal RA patients compared with the postmenopausal RA patients. SEM images showed denser clots composed of thinner fibers in samples from RA patients. The disease activity measured by DAS28 correlated with OCP and OHP (r = 0.54; p = 0.001 and r = 0.44; p = 0.003, respectively) indicating persistent hypercoagulable condition in the whole group of RA patients. Conclusions: Our results point towards coagulation activation in premenopausal women with established RA. The patients were well characterized, which enabled assessment in a real-life setting.Key Points• Extensive assessment points towards persistent coagulation activation in premenopausal women with established rheumatoid arthritis.• Impaired thrombin generation and fibrin formation are associated with menopause in healthy women, while rheumatoid arthritis closes the gap within patients regarding menopause.• Fibrin morphology is unfavorably altered and fibrinolysis is decreased in patients with established rheumatoid arthritis.• Increased activity of thrombin activatable fibrinolysis inhibitor (TAFI) may contribute to impaired fibrinolysis in patients with rheumatoid arthritis
Effects of Provinols on Cardiodynamics and Coronary Flow in Islodated Rat Hearts
Provinols are an alcohol-free extract of red wine that contains a wide range of polyphenols. Polyphenols are a group of chemical compounds found in diverse plants. Polyphenols are considered to protect against cardiovascular disease. Although some older epidemiological studies have indicated that the positive effects of red wine on heart disease can be attributed to the alcohol content alone, there is now powerful evidence that polyphenols present in red wine are responsible for these positive effects. The hearts of male Wistar albino rats (n = 36, 12 in each experimental group, 10 weeks old, body mass 250 ± 30 g) were excised and retrogradely perfused according to the Langendorff technique at a gradually increasing perfusion pressure (40-120 cmH2O). Parameters of cardiac function (dp/dt max, dp/dt min, SLVP, DLVP, HR, CF) were measured after perfusion with three different concentrations of provinols (5 μg/ml, 10 μg/ml and 50 μg/ml). Administration of the highest dose (50 μg/ml) induced a significant increase in dp/dt max, dp/dt min, HR and CF compared with control conditions at CPP = 40 cmH2O, while an intermediate dose increased dp/dt max at the same CPP. Generally viewed, the results of the present study suggest that provinols may have a beneficial effect on the intact myocardium and coronary circulation. These findings could constitute an important step in further investigation of these polyphenols under different representative experimental conditions in the heart, as well as providing a good basis for potential clinical studies in this field
Does cholesterol bound to haemoglobin affect the anti-oxidant enzyme defence system in human erythrocytes?
In a previous study, it was shown that the lipid fraction, which is occasionally observed in red blood cell hemolysates, represents cholesterol (Ch) associated with phospholipid firmly bound to haemoglobin (termed Hb-Ch). The current study was conducted to investigate whether Hb-Ch could affect the primary anti-oxidant enzyme defence system in human erythrocytes. Sixty healthy volunteers were used for the current study. Group 1 consisted of 28 subjects without or with a low level of Hb-Ch. Group 2 comprised 32 subjects with a considerably higher level of Hb-Ch. The activities of erythrocyte superoxide dismutase, catalase, glutathione peroxidase and glutathione reductase, as well as the content of methaemoglobin (metHb) were measured in both groups. The results indicated that the amount ofHb-Ch neither influenced the activities of the erythrocyte anti-oxidant enzymes nor altered the level of metHb. However, a higher amount ofHb-Ch changed the correlations in the part of the anti-oxidant defence system relating to glutathione, suggesting increased peroxidative pressure from plasma lipids. Group 2 also had significantly increased concentrations of total plasma Ch and triglycerides. Together, these facts are strong indications that the anti-oxidant defence system in human erythrocytes finely retunes its composition according to plasma oxidative demands