A reliable chromatographic method for the simultaneous determination of ciprofloxacin and moxifloxacin in human serum

Purpose: To develop and validate a simple chromatographic method for the analysis of ciprofloxacin and moxifloxacin in human serum.Methods: After protein precipitation had been performed, high performance liquid chromatography (HPLC) with UV detection was utilized for the analysis of ciprofloxacin and moxifloxacin in human serum. Analytical column Zorbax SB-C18 (150 mm x 4.6 mm i.d., particle size 3.5 μm) was used as a stationary phase. Chromatographic separation was realized with the mobile phase 0.1% trifluoroacetic acid in water for chromatography - methanol (66:34, v/v), at the flow rate of 1 mL/min, temperature of 35 oC and detection at 280 nm. The method validation was performed according to the guidelines of the European Medicines Agency (EMA).Results: The chromatographic run time was about 12 minutes and no interference was observed. For ciprofloxacin, the method was linear over a concentration range of 0.5-50 μg/mL, with a correlation coefficient of 0.9874. For moxifloxacin, the method was linear over a concentration range of 0.5-50 μg/mL, with a correlation coefficient of 0.9946. Since relative standard deviation (RSD) and relative recovery values were within acceptable limits according to EMA guidelines, good intra-day precision, inter-day precision, as well as the accuracy of the method, were observed.Conclusion: A simple and reliable HPLC-UV method has been developed and validated for the simultaneous determination of ciprofloxacin and moxifloxacin in human serum. The method can be applied for therapeutic drug monitoring but also and pharmacokinetic studies of ciprofloxacin and moxifloxacin. Keywords: Human serum, Ciprofloxacin, Moxifloxacin, Protein precipitation, HPLC, UV detection, Method validatio

Non-invasive treatment of multiple enamel hypoplasia: A case report

Objective. Enamel hypoplasia is a quantitative disorder of enamel deposition during the secretory phase and is characterised by a deficiency of the enamel, while hypomineralization is a qualitative disorder caused by incomplete mineralization and maturation of the enamel, followed by the porosity of the solid dental tissues and the opalescent tooth colour. Clinically, hypoplasia is a risk for caries, tooth sensitivity, erosion, and affects the aesthetic appearance of a patient with a psychological connotation. The aim of the paper is to present the case report, the possibility of preventive measures and restorative treatments with minimally invasive requirements in these patients. Methods. At the Faculty of Medical Sciences, University of Kragujevac, in March 2018, a thirteen-year-old boy was diagnosed with isolated hypoplastic enamel defects on teeth 24, 25, 26, 33 and 34. Results. Enamel hypoplasia was diagnosed by anamnesis, clinical and radiological examination. Preventive measures and conservative interventions were used to prevent progressive abrasion and early tooth loss due to caries and its complications. Conclusion. Early diagnosis, timely preventive methods and minimally invasive restorative treatment can correct anomalies and prevent possible complications.Publishe

Procena težine simptoma alergijskog rinitisa vizuelnom analognom skalom

Objective. To examine the characteristics of patients with allergic rhinitis and assess the severity of symptoms by using a visual analog scale. Methods. A prospective study was carried out among allergic rhinitis patients, who were referred by the primary care physician to the ENT Department of Health Centre Kragujevac. The assessment of severity of symptoms was performed using visual analog scale (overall influence of all nasal or nasal and ocular symptoms, VAS score of 0 'nasal or nasal and ocular symptoms do not bother' to 10 'nasal or nasal and ocular symptoms are extremely bothered') during the first examination. Data was statistically analysed with descriptive statistical methods, t-test, x2 test and logistic regression using by standard statistical software package (SPSS for Windows, version 19.0). Results. Among our respondents there were 34.3% (37/108) males and 65.7% (71/108) females. Average age of all patients was 29 ± 15,1. Average duration of disease in the sample studied was 7,2 ± 16,2 years. The majority of our participants were classified as having moderate to severe persistent allergic rhinitis. Severity of disease has a greater impact on the VAS score of disease duration. Average VAS score of all participants were 6,9±4,2. It was found that the severity of the disease and the presence of ocular symptoms in patients with allergic rhinitis have an impact on the VAS score (p lt 0,0001) while the use of therapy and sensitization to inhalant allergens did not have such impact. Conclusion. Visual analog scale is a simple quantitative method to assess the severity of allergic rhinitis.Cilj. Proceniti težinu simptoma metodom vizuelne analogne skale kod obolelih od alergijskog rinitisa. Metode: Sprovedena je prospektivna studija u kojoj su analizirani oboleli od alergijskog rinitisa, koje su izabrani lekari upućivali na ORL odeljenje specijalističko-konsultativne službe Doma zdravlja 'Kragujevac'. Težina simptoma procenjena je vizuelnom analognom skalom (ukupan uticaj svih nazalnih ili nazalnih i okularnih simptoma, VAS skor od nula - 'nazalni ili nazalni i okularni simptomi uopšte ne smetaju', do 10 - 'nazalni ili nazalni i okularni simptomi izuzetno smetaju') prilikom prvog pregleda. Statistički značajnim smatrane su vrednosti za p lt 0,05. Podaci su statistički obrađeni primenom deskriptivnog metoda, t-testa, X2-testa i logističke regresije standardnim statističkim paketom (SPSS za Windows, verzija 19.0). Rezultati. Među našim ispitanicima bilo je 34,3% (37/108) osoba muškog pola, dok je osoba ženskog pola bilo 65,7% (71/108). Starost svih ispitanika bila je 29 ± 15,1. Prosečna dužina trajanja bolesti u ispitivanom uzorku bila je 7,2 ± 16,2 godine. Najviše ispitanika imalo je umereno do težak perzistentan oblik bolesti. Prosečna vrednost VAS skora za sve ispitanike bila je 6,9 ± 4,2. Primenom logističke regresije ustanovljeno je da težina bolesti ima veći uticaj na VAS skor od trajanja bolesti. Utvrđeno je da težina bolesti i prisustvo okularnih simptoma kod obolelih od alergijskog rinitisa ima veći uticaj na VAS skor (p lt 0,0001), dok primena terapije i senzibilizacija na inhalatorne alergene nema. Zaključak. Vizuelna analogna skala je jednostavan kvantitativan metod za procenu težine alergijskog rinitisa

Exploring if Porphyra sp. extract functions as serum substitute in HT29 cell culture

This study investigates the impact of Porphyra sp. extracts on HT29 cell line growth and viability at reduced serum conditions. The concentration-dependent effects of phycobiliproteins (PBPs) on cell proliferation were examined over various time intervals. Lower concentrations of PBPs (20 μg/mL) demonstrated an increase in HT29 cell viability after 48 hours and 5 days of cultivation at reduced serum concentration (final serum concentration was in the range from 5 to 8%). This suggests a potential positive influence on cell proliferation, likely due to their antioxidant properties. Conversely, higher concentrations of PBPs exhibited inhibitory effects on cell growth, possibly due to cytotoxicity at elevated levels. Remarkably, when HT29 cells were cultured solely in algal extract without fetal calf serum (FCS), complete growth inhibition was observed after 72 hours. This finding underscores the insufficient nutrient and growth factor provision of PBPs alone for sustaining cell viability. Morphological differences observed in cells cultured with 70 μg/mL of PBPs indicated potential alterations in cellular morphology. Notably, 70 μg/mL of PBPs in RPMI medium with 5% FCS displayed growth inhibition compared to the control (5% FCS). Furthermore, we assessed HT29 cell adaptability to changes in FCS concentration and PBP supplementation. Cells incubated under varying FCS and PBP conditions were subcultured into RPMI medium with lower FCS concentration and PBPs from Porphyra. The viability of cells following subculturing indicated sustained adaptability to reduced FCS levels. Overall, this study provides valuable insights into the concentration-dependent effects of PBPs from Porphyra extracts on HT29 cell growth and viability. The findings underscore the potential benefits of PBPs at lower concentrations for cell proliferation at reduced serum conditions and reveal the adaptability of HT29 cells to changing culture conditions

Exploring if Porphyra sp. extract functions as serum substitute in HT29 cell culture

This study investigates the impact of Porphyra sp. extracts on HT29 cell line growth and viability at reduced serum conditions. The concentration-dependent effects of phycobiliproteins (PBPs) on cell proliferation were examined over various time intervals. Lower concentrations of PBPs (20 μg/mL) demonstrated an increase in HT29 cell viability after 48 hours and 5 days of cultivation at reduced serum concentration (final serum concentration was in the range from 5 to 8%). This suggests a potential positive influence on cell proliferation, likely due to their antioxidant properties. Conversely, higher concentrations of PBPs exhibited inhibitory effects on cell growth, possibly due to cytotoxicity at elevated levels. Remarkably, when HT29 cells were cultured solely in algal extract without fetal calf serum (FCS), complete growth inhibition was observed after 72 hours. This finding underscores the insufficient nutrient and growth factor provision of PBPs alone for sustaining cell viability. Morphological differences observed in cells cultured with 70 μg/mL of PBPs indicated potential alterations in cellular morphology. Notably, 70 μg/mL of PBPs in RPMI medium with 5% FCS displayed growth inhibition compared to the control (5% FCS). Furthermore, we assessed HT29 cell adaptability to changes in FCS concentration and PBP supplementation. Cells incubated under varying FCS and PBP conditions were subcultured into RPMI medium with lower FCS concentration and PBPs from Porphyra. The viability of cells following subculturing indicated sustained adaptability to reduced FCS levels. Overall, this study provides valuable insights into the concentration-dependent effects of PBPs from Porphyra extracts on HT29 cell growth and viability. The findings underscore the potential benefits of PBPs at lower concentrations for cell proliferation at reduced serum conditions and reveal the adaptability of HT29 cells to changing culture conditions

Dimethylarginine – biomarkers in progression of kidney disease / Dimetilarginini – biomarkeri u progresiji bubrežnih oboljenja

Summary Decreased nitric oxide (NO) production and/or impaired NO bioavailability may occur in patients with the chronic kidney disease (CKD), and could contribute to elevation of blood pressure, cardiovascular disease (CVD) and progression of renal injury in these patients. Free guanidinomethylated arginine residues occur endogenously as a result of proteolysis of post-translational methylated tissue proteins. The asymmetric dimethyl arginine (ADMA) is a competitive inhibitor of the nitric oxide synthase (NOS) enzymes. The kidney has a predominant role in ADMA elimination by combining two mechanisms; urinary excretion and metabolization of ADMA The degradation of ADMA is accomplished intracellularly by the enzyme dimethylarginine dimethylaminohydrolase (DDAH). ADMA is not only a uremic toxin, but also a strong marker of the endothelial dysfunction and atherosclerosis and a stronger independent predictor of all-cause mortality and cardiovascular outcome in patients with the chronic renal failure. There are at least four mechanisms that may explain the accumulation of ADMA in CKD: increased methylation of proteins, increased protein turnover, decreased metabolism by DDAH and impaired renal excretion. A strong positive correlation between symmetric dimethyl arginine (SDMA) and creatinine suggests that SDMA might be of value as a marker of the renal function. Reduced NO elaboration secondary to accumulation of ADMA and elevated inflammation may be important pathogenic factors for endothelial dysfunction in patients with the renal disease. Elevation of ADMA may be a missing link between CVD and CKD

Regioselective protein oxidative cleavage enabled by enzyme-like recognition of an inorganic metal oxo cluster ligand

Oxidative modifications of proteins are key to many applications in biotechnology. Metal-catalyzed oxidation reactions efficiently oxidize proteins but with low selectivity, and are highly dependent on the protein surface residues to direct the reaction. Herein, we demonstrate that discrete inorganic ligands such as polyoxometalates enable an efficient and selective protein oxidative cleavage. In the presence of ascorbate (1 mM), the Cu-substituted polyoxometalate K8[Cu2+(H2O)(α2-P2W17O61)], (CuIIWD, 0.05 mM) selectively cleave hen egg white lysozyme under physiological conditions (pH =7.5, 37 °C) producing only four bands in the gel electropherogram (12.7, 11, 10, and 5 kDa). Liquid chromatography/mass spectrometry analysis reveals a regioselective cleavage in the vicinity of crystallographic CuIIWD/lysozyme interaction sites. Mechanistically, polyoxometalate is critical to position the Cu at the protein surface and limit the generation of oxidative species to the proximity of binding sites. Ultimately, this study outlines the potential of discrete, designable metal oxo clusters as catalysts for the selective modification of proteins through radical mechanisms under non-denaturing conditions

Prevalence, associated factors and outcomes of pressure injuries in adult intensive care unit patients: the DecubICUs study

Funder: European Society of Intensive Care Medicine; doi: http://dx.doi.org/10.13039/501100013347Funder: Flemish Society for Critical Care NursesAbstract: Purpose: Intensive care unit (ICU) patients are particularly susceptible to developing pressure injuries. Epidemiologic data is however unavailable. We aimed to provide an international picture of the extent of pressure injuries and factors associated with ICU-acquired pressure injuries in adult ICU patients. Methods: International 1-day point-prevalence study; follow-up for outcome assessment until hospital discharge (maximum 12 weeks). Factors associated with ICU-acquired pressure injury and hospital mortality were assessed by generalised linear mixed-effects regression analysis. Results: Data from 13,254 patients in 1117 ICUs (90 countries) revealed 6747 pressure injuries; 3997 (59.2%) were ICU-acquired. Overall prevalence was 26.6% (95% confidence interval [CI] 25.9–27.3). ICU-acquired prevalence was 16.2% (95% CI 15.6–16.8). Sacrum (37%) and heels (19.5%) were most affected. Factors independently associated with ICU-acquired pressure injuries were older age, male sex, being underweight, emergency surgery, higher Simplified Acute Physiology Score II, Braden score 3 days, comorbidities (chronic obstructive pulmonary disease, immunodeficiency), organ support (renal replacement, mechanical ventilation on ICU admission), and being in a low or lower-middle income-economy. Gradually increasing associations with mortality were identified for increasing severity of pressure injury: stage I (odds ratio [OR] 1.5; 95% CI 1.2–1.8), stage II (OR 1.6; 95% CI 1.4–1.9), and stage III or worse (OR 2.8; 95% CI 2.3–3.3). Conclusion: Pressure injuries are common in adult ICU patients. ICU-acquired pressure injuries are associated with mainly intrinsic factors and mortality. Optimal care standards, increased awareness, appropriate resource allocation, and further research into optimal prevention are pivotal to tackle this important patient safety threat

Correction to: Prevalence, associated factors and outcomes of pressure injuries in adult intensive care unit patients: the DecubICUs study

The original version of this article unfortunately contained a mistake