Logo

Publikacije (116)

Nazad
D. Korovljev, J. Ostojić, N. Todorović, S. Ostojić

Introduction We evaluated whether 12-week intake of molecular hydrogen (H2) in 5 overweight adults (3 women; age: 50.2 ±11.9 years, body mass index: 29.4 ±2.1 kg/m2) affects brain levels of the glutamate-glutamine-GABA cycle, critical amino acid neurotransmitters in the mechanism of neuronal activation during appetite regulation. Methods A 1.5-T single-voxel proton magnetic resonance spectroscopy was used to assess the tissue concentrations of relevant metabolites. Results The mean glutamate and glutamate-plus-glutamine levels at the posterior cingulate gyrus decreased significantly during the study; this was accompanied by a significant drop in GABA levels at left prefrontal white matter, and glutathione levels at anterior cingulate gyrus. No changes in the brain metabolites were found in the comparable group of overweight individuals (n = 4, 2 women; age: 41.0 ±13.9, BMI 26.8 ±1.3 kg/m2) followed-up in the past without this treatment. Conclusions We showed a possible hydrogen-driven upregulation of neurotransmitters involved in appetite stimulation leading to hunger suppression and weight loss. Further studies analyzing appetite-controlling metabolic pathways affected by H2 would require monitoring of additional biomarkers of satiation and satiety during different feeding regimens.

D. Korovljev, Dejan Javorac, N. Todorović, Marijana Ranisavljev, D. Engeset, Tonje Holte Stea, J. Ostojić, Katarina Bijelić et al.

The aim of this randomized controlled trial was to analyze the effects of medium-term supplementation with hydrogen-rich water on brain metabolism, appetite-regulating hormones, body composition, and safety biomarkers in overweight adults. Twenty (n = 20, 10 females) apparently healthy adults with a body mass index >24.9 kg/m2 were assigned to receive 0.5 L per day of hydrogen-rich water (7.5 mg of hydrogen) or hydrogen-free water (tap water) for 12 weeks. Two-way analysis of variance with repeated measures revealed a significant difference between the two interventions in several body composition indices (P ≤ 0.05), with hydrogen-rich water superior to placebo to reduce waist circumference and mid-upper arm circumference by 1.31 cm (95% confidence interval, from –0.23 to 2.85) and 0.65 cm (95% confidence interval, from –0.10 to 1.40), respectively. Hydrogen-rich water outcompeted placebo to raise serum ghrelin levels, as the mean difference from the placebo group was 17.28 pmol/L (95% confidence interval, from 1.81 to 32.75) (P = 0.02). A non-significant strong positive trend (P = 0.10) was reported toward hydrogen-rich water being superior to placebo in augmenting total serum short-chain fatty acid levels, with a mean difference from the control group of 195.6 μmol/L (95% confidence interval, from –64.55 to 275.85). The mean fecal calprotectin levels were significantly reduced after hydrogen-rich water intervention for 19.7 μg/mg (95% confidence interval, from 0.31 to 39.09) (P = 0.03). Our findings advance hydrogen-rich water as a promising metabolic intervention in overweight adults, but further validation via multicentric longitudinal randomized controlled trials in metabolic and nutritional disorders is required.

S. Ostojić, Marijana Ranisavljev, J. Slankamenac, N. Todorović, J. Ostojić, V. Štajer

Dejana Bajić, J. Matijašević, L. Andrijevic, B. Zarić, M. Lalic-Popovic, I. Andrijević, N. Todorović, A. Mihajlović et al.

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) caused a global pandemic and one group of patients has developed a severe form of COVID-19 pneumonia with an urgent need for hospitalization and intensive care unit (ICU) admission. The aim of our study was to evaluate the prognostic role of MDW, CRP, procalcitonin (PCT), and lactate in critically ill COVID-19 patients. The primary outcome of interest is the 28 day mortality of ICU patients with confirmed SARS-CoV-2 infection and sepsis (according to Sepsis 3 criteria with acute change in SOFA score ≥ 2 points). Patients were divided into two groups according to survival on the 28th day after admission to the ICU. Every group was divided into two subgroups (women and men). Nonparametric tests (Mann–Whitney) for variables age, PCT, lactate, and MDW were lower than alpha p < 0.05, so there was a significant difference between survived and deceased patients. The Chi-square test confirmed statistically significant higher values of MDW and lactate in the non-survivor group. We found a significant association between MDW, lactate, procalcitonin, and fatal outcome, higher values were reported in the deceased group.

S. Ostojić, J. Ostojić, D. Zanini, Tatjana Jezdimirović, V. Štajer

Acute secondary progressive multiple sclerosis (SPMS) is characterized by escalating neurological disability, with limited disease-modifying therapeutic options. A 48-year-old woman with acute SPMS being treated with interferon beta-1a and oral corticosteroids presented as a clinical outpatient with no disease-modifying effects after treatment. A decision was made to treat her with a combination of guanidinoacetate and creatine for 21 days. She had made clinical progress at follow-up, with the intensity of fatigue dropping from severe to mild. Magnetic resonance spectroscopy revealed increased brain choline, creatine, N-acetylaspartate, and glutathione. Patients with SPMS may benefit from guanidinoacetate–creatine treatment in terms of patient- and clinician-reported outcomes; this requires additional study.

Alma Brakus, J. Ostojić, M. Lucic

Background: Pretreatment differentiation between glioblastoma and metastasis is a frequently encountered dilemma in neurosurgical practice. Distinction is required for precise planning of resection or radiotherapy, and also for defining further diagnostic procedures. Morphology and spectroscopy imaging features are not specific and frequently overlap. This limitation of magnetic resonance imaging and magnetic resonance spectroscopy was the reason to initiate this study. The aim of the present study was to determine whether the dataset of diffusion tensor imaging metrics contains information which may be used for the distinction between primary and secondary intra-axial neoplasms. Methods: Two diffusion tensor imaging parameters were measured in 81 patients with an expansive, ring-enhancing, intra-axial lesion on standard magnetic resonance imaging (1.5 T system). All tumors were histologically verified glioblastoma or secondary deposit. For qualitative analysis, two regions of interest were defined: intratumoral and immediate peritumoral region (locations 1 and 2, respectively). Fractional anisotropy and mean difusivity values of both groups were compared. Additional test was performed to determine if there was a significant difference in mean values between two locations. Results: A statistically significant difference was found in fractional anisotropy values among two locations, with decreasing values in the direction of neoplastic infiltration, although such difference was not observed in fractional anisotropy values in the group with secondary tumors. Mean difusivity values did not appear helpful in differentiation between these two entities. In both groups there was no significant difference in mean difusivity values, neither in intratumoral nor in peritumoral location. Conclusion: The results of our study justify associating the diffusion tensor imaging technique to conventional morphologic magnetic resonance imaging as an additional diagnostic tool for the distinction between primary and secondary intra-axial lesions. Quantitative analysis of diffusion tensor imaging metric, in particular measurement of fractional anisotropy in peritumoral edema facilitates accurate diagnosis.

D. Muršić, T. Jalušić Glunčić, J. Ostojić, S. Škrinjarić-Cincar, Ljiljana Bulat Kardum, Martina Dokoza, A. Rožman, N. Karamarković Lazarušić et al.

N. Todorović, D. Zanini, V. Štajer, D. Korovljev, J. Ostojić, S. Ostojić

Abstract The main aim of this randomized‐controlled cross‐over interventional trial was to assess the acute effects of taking a single dose of hydrogen‐rich water (HRW), and compare it with caffeine, HRW plus caffeine, and control water, for alertness, brain metabolism, brain and oxygen saturation, and self‐reported adverse events in healthy men and women who were habitual coffee drinkers and were sleep‐deprived for 24 hr. Sixteen apparently healthy young adults (8 men and 8 women; age 24.0 ± 3.5 years) were allocated in a cross‐over design to receive a single‐dose drink of HRW (8 ppm), caffeine (50 mg), HRW plus caffeine, or control drink (tap water) in the morning after 24‐hr sleep deprivation and 12‐hr fasting. The primary and secondary outcomes were assessed at baseline (pre‐intervention) and 15‐min follow‐up. Significantly less time was needed to complete trail‐making test after both HRW and HRW plus caffeine compared with the control drink (p < .05). The number of errors in the symbol digit modalities test was significantly lower after drinking HRW or caffeine than control drink (p < .05). Both HRW and caffeine significantly increased the choline‐to‐creatine ratio in several brain regions (frontal white and gray matter), while HRW and the combination intervention also affected brain metabolism in the paracentral brain. No participants reported any side effects from any intervention. The attention enhancement driven by HRW appears along with changes in brain metabolism. Being generally recognized as a safe intervention, hydrogen could be thus recommended as a novel intervention that upholds attention in stressed conditions, with its metabolic footprint likely different from caffeine.

S. Kovačević, S. Spasić, S. Lopicic, J. Todorović, Marko Dinčić, M. Stanojević, J. Ostojić

Cadmium (Cd2+) is toxic metal and environmental pollutant. Accumulation of cadmium in the kidney results initially in proximal tubule dysfunction. Although Cd2+ toxicity is well documented, all mechanisms that are involved in the early stages of nephrotoxicity, especially considering low micromolar concentrations of Cd2+ ions are still unknown. The Aim of this study was to investigate the effects acute exposure to different peritubular micromolar concentrations of cadmium (0.25, 0.50, 1.0, 2.0, 3.0, 5.0 μmol/L) on the peritubular cell membrane potential in proximal tubular cells of frog kidney. The experiments were performed on isolated, doubly perfused kidneys of Rana esculenta of both sexes. Aortic and portal vein were cannulated in order to perfusate luminal and peritubular cell membraine. In controled conditions, Ringer solution was simultaneously used to perfusate both cell membraines. Cadmium chloride (different concentrations: 0.25, 0.50, 1.0, 2.0, 3.0, 5.0 μmol/L) were added to the peritubular perfusate separately, by switching the peritubular perfusate from the control Ringer solution to Ringer solution with addition of cadmium ions. Peritubular cell membrane potentials (PD) were measured with conventional 3 mol/L KCl microelectrodes. The peritubular application of different micromolar Cd2+ concentrations led to a rapid, sustained, reversible hyperpolarization of the peritubular cell membrane: 0.25 µmol/L, by −3.3±0.4 mV (n=8, p<0.001); 0.50 µmol/L, by −3.0±0.5 mV (n=11, p<0.001); 1.0 µmol/L, by −2.9±0.6 mV (n=8, p<0.01); 2.0 µmol/L, by −4.2±0.4 mV (n=13, p<0.01); 3.0 µmol/L, by −3.4±0.3 mV (n=14, p<0.001); 5.0 µmol/L, by −3.0±0.4 mV (n=10, p<0.001). After switching the perfusion from Ringer solution with addition of cadmium ions to control Ringer, the peritubular membraine potential returned to the average values that were maintained before the peritubular Cd2+ application (p>0.05). Comparing the effect of different Cd2+ concentrations, there was no difference in the hyperpolarization of the peritubular cell membrane (p>0.05).Each cell served as its own control. Different low micromolar concentrations of Cd2+ provoked rapid and sustained hyperpolarization of peritubular membrane potential that did not show concentration-dependent response.

A. N. Grassino, J. Ostojić, Vicenzia Miletić, Senka Djaković, T. Bosiljkov, Z. Zorić, D. Ježek, Suzana Rimac Brnčić et al.

Nema pronađenih rezultata, molimo da izmjenite uslove pretrage i pokušate ponovo!

Pretplatite se na novosti o BH Akademskom Imeniku

Ova stranica koristi kolačiće da bi vam pružila najbolje iskustvo

Saznaj više