Wojciech Rokicki

Liver regeneration in rats after complete and partial occlusion of the portal blood influx

The role of portal blood influx in liver regeneration was studied in rats. Partial hepatectomy with removal of 45% of the liver mass was performed after end-to-side portacaval shunt (PCS) leading to complete diversion of portal blood from the liver, or after side-to-side PCS causing partial portal blood deprivation. Liver resection was limited to 45% to avoid the high mortality rate in rats with vascular anastomoses and 70% hepatectomy, but it did not change the pattern of liver regeneration. The total RNA and DNA content, the rate of DNA synthesis and the number of hepatocyte mitoses in regenerating liver were measured in comparison to sham-operated controls. Complete occlusion of the portal blood influx did not block hepatoproliferative response, but caused a significant decrease and delay of regeneration. Partial preservation of portal flow in rats with side-to-side PCS markedly improved liver regeneration in comparison to end-to-side PCS, but the process was slower than in the control group.

The role and importance of club cells (Clara cells) in the pathogenesis of some respiratory diseases

The report presents the cellular structure of the respiratory system as well as the history of club cells (Clara cells), their ultrastructure, and location in the airways and human organs. The authors discuss the biochemical structure of proteins secreted by these cells and their importance for the integrity and regeneration of the airway epithelium. Their role as progenitor cells for the airway epithelium and their involvement in the biotransformation of toxic xenobiotics introduced into the lungs during breathing is emphasized. This is followed by a discussion of the clinical aspects associated with club cells, demonstrating that tracking the serum concentration of club cell-secreted proteins is helpful in the diagnosis of a number of lung tissue diseases. Finally, suggestions are provided regarding the possible use of proteins secreted by club cells in the treatment of serious respiratory conditions.

Oxidative stress in the red blood cells of patients with primary open-angle glaucoma

BACKGROUND This study was designed to examine oxidative and antioxidative changes in the red blood cells (RBCs) of patients presenting with glaucomatous degeneration. METHODS The experimental design was a case-control study of strictly selected patients who required antiglaucomatous surgery during primary open-angle glaucoma despite relatively regulated intraocular pressure (IOP) (POAG group, n = 30) and patients who underwent an operation for nonpathological cataracts (cataract group, n = 25). The activities of total superoxide dismutase (SOD), glutathione peroxidase (GPX), and catalase (CAT), as well as the concentration of malondialdehyde (MDA), were measured. Glaucomatous damage was estimated from a transient pattern electroretinogram. RESULTS Significant increases in GPX (p = 0.026) and CAT (p = 0.000) activity were noted in the RBCs of POAG patients compared to those of cataract patients. Although SOD was elevated in patients with POAG, the differences compared to cataract controls were not significant (p = 0.079). MDA concentrations were significantly increased in the glaucoma group compared to the cataract controls. CONCLUSION An oxidative disorder primarily represented by catalase upregulation was observed during the course of glaucoma.

The Original Experimental Model in Rats to Study Gastric Banding Surgery

BackgroundA new bariatric surgical experimental model in rats for aspects of investigation was created.MethodsIn 121 male Wistar rats with body mass 250–270 g, the original gastric banding (GB) operation was performed. Sixty days after the surgical procedure, we measured body mass and upper part of the alimentary tract patency (radiography with contrast medium).ResultsOne hundred twenty one rats were operated on. In the study group, the mortality was 0%. A complication (incisional hernia) was found in only three cases. The average weight of the rat in the GB group on the 60th day after the surgery was 355.0 ± 4.12 g, and that in the sham-operation group was 394.0 ± 4.80 g (t test, t = 6,073, p < 0.001). The daily weight gain in sham-operated rats was 2.23 ± 0.07 g, whereas in the GB group, it was 1.60 ± 0.07 g (p < 0.02). Complete inhibition of weight gain was not observed.ConclusionThe rat model of GB surgery that we created is easy to perform, repeatable, long-lasting, relatively cheap, and can be used in various experimental trials of diverse aspects of surgery in the field of obesity.

Inducible and Endothelial Nitric Synthetase Expression and Nitrotyrosine Accumulation in Iris Vasculature of Patients with Primary Open-Angle Glaucoma: A Pilot Study

Background The “double-faced” effect of nitric oxide (NO) is thought to play an important role in triggering and progression of glaucoma. Material/Methods Iris samples were obtained during iridectomy in 35 patients (mean age of 65.4±5.3 years) with diagnosed primary open-angle glaucoma (POAG). The controls were collected postmortem from 10 donors with a mean age of 62.2±1.9 years. Visual field defects were evaluated by perimetry. The Hodapp-Parrish-Anderson classification was used to divide patients into 3 visual field defect groups. The intraocular pressure was measured 3 times before surgery using applanation tonometry. The phenotype activity of nitric oxide synthase (NOS) isoenzymes (endothelial – eNOS and inducible – iNOS) and expression of nitrotyrosine in iris vasculature was assessed. Results Significant differences were found between glaucoma patients and the controls in eNOS and iNOS activity (Mann-Whitney test, U=35.5, Z=−2.037, p=0.04 and U=21, Z=2.69, p=0.007, respectively). In addition, the results showed an upregulation of nitrotyrosine in the capillary endothelial cells in the study group, which was associated with the duration of diagnosed glaucoma (R-Spearman of 0.33, p=0.0047) and visual field mean defect MD (R-Spearman of 0.29, p=0.019). Moreover, the activity of nitrotyrosine was significantly correlated with iNOS immunoreactivity (R-Spearman of 0.5, p=0.0001). However, the iNOS activity significantly varied among Hodapp-Parrish-Anderson groups (p=0.03). Conclusions Our observations confirmed the association between glaucomatous disturbances and upregulation of iNOS, together with increased nitrotyrosine storage.

von Willebrand factor in iris vasculature of glaucoma patients

Background Previous reports have indicated the role of endothelium disturbances, as expressed by von Willebrand factor (vWF) release, in pathophysiology of glaucoma. The objective of this study was to investigate the vWF expression in iris vasculature of patients with primary open-angle glaucoma (POAG). Material/Methods Immunohistochemistry of vWF expression was performed on cryostat sections of samples collected at the time of peripheral iridectomy and controls collected from dead donors. Results Twenty-seven Caucasians age 66.6±3.7 with 5.8±3.7-year history of treated PAOG and 10 controls age 62.2±1.92 with no history of glaucoma. The percentage of patients who presented normal and up-regulation of vWF phenotype expression differed statistically between examined and control groups: 48% versus 100% (p=0.035, chi-square test with Yates’ correction). Sex, age, glaucoma duration, and visual field quantitative indices had no impact on vWF expression. A significant correlation between mean pre-surgery intraocular pressure and vWF expression was found (Spearman r=0.42, p=0.03). Conclusions Considering the results, it may be suggested that vWF is actively involved in the pathophysiology of glaucoma.

Combination of bevacizumab and bromfenac therapy in age-related macular degeneration: A pilot study

Background According to recent studies, the newest strategy for the treatment of exudative age-related macular degeneration is to combine anti-VEGF agents with non-steroid anti-inflammatory drugs (NSAIDs) such as nepafenac and bromfenac to decrease the frequency of intravitreal injections. Since most research has focused on ranibizumab, the aim of this study is to evaluate whether an alternative drug such as bevacizumab could lead to similar outcomes. Material/Methods The study was conducted on a group of 26 patients who were administered intravitreal bevacizumab and topical bromfenac (study group) and 26 patients with single bevacizumab therapy (control group). Cases that were not qualified for ranibizumab therapy were included in the study group. Results The study revealed that the visual acuity and parameters observed in OCT improved more in the study group than in the control group. However, the correlations between the above factors and the frequency of intravitreal injections were statistically significant only in visual acuity. Conclusions We recommend the combined therapy of bevacizumab and bromfenac as an alternative and beneficial method of treatment in patients with exudative AMD who do not qualify for ranibizumab therapy. This combined therapy might efficiently reduce the number of intravitreal injections of bevacizumab.

Effect of Selected Dietary Compounds on Extracellular Superoxide Dismutase in the Vitreous of Chinchillas

Purpose: The purpose of this study was to evaluate the effect of diet on the extracellular superoxide dismutase (EC-SOD) activity in the vitreous of chinchillas. Methods: Seventy-eight male chinchillas were randomly divided into 7 subgroups: controls, receiving a standard basal diet, and 6 experimental groups additionally receiving 10% nonoxidized and 10% oxidized olive oil, a garlic extract and lipoic acid in their diet. The activities of EC-SOD were measured. Results: The highest EC-SOD activity was similar in the controls [2.17 ± 0.27 nitric units (NU)/mg protein] and in rabbits fed oxidized olive oil (2.29 ± 0.31 NU/mg protein; p = 0.519). Nonoxidized olive oil appeared to be the strongest antioxidant component of diet (1.58 ± 0.20 NU/mg protein) as compared with the subgroups above (p = 0.008 and p = 0.012, respectively). Administration of garlic and lipoic acid decreased the SOD activity only inthe groups fed oxidized olive oil (p = 0.014). Conclusions: The SOD activity in laboratory animals is possibly modulated by diet. Work will be continued to extrapolate these results to humans.

Malignant mesothelioma as a difficult interdisciplinary problem

The authors of the present report review the etiology and clinical symptoms of malignant pleural mesothelioma (MPM) as well as diagnostic techniques (both radiological and biomarkers) used for its detection. Subsequently, they present methods of multimodal treatment (surgery, chemotherapy, and radiotherapy) recommended by the International Mesothelioma Interest Group (IMIG). Finally, they discuss complications and long-term results associated with these methods of MPM treatment.

Differences in serum oxidative status between glaucomatous and nonglaucomatous cataract patients

BackgroundOxidative stress contributes to both intraocular pressure regulation and glaucomatous neuropathy. The systemic redox status (solitary determination) was examined in primary open-angle glaucoma (POAG) patients with cataract and nonglaucomatous cataract patients. Cataract-matched group comparisons appear more precise in the context of oxidative stress evaluation. The aim of this study was to establish if systemic oxidative status in POAG patients was elevated compared with the cataract only subjects.MethodsThe study included patients with primary open angle glaucoma (POAG group, n = 30) and controls (non POAG group, n = 25). Serum concentration of lipofuscine (LPS), malondialdehyde (MDA) and activity of total superoxide dismutase (SOD), and its mitochondrial (Mn-SOD) and cystolic (Cu,Zn-SOD) isoform were measured. Total oxidant state (TOS) and total antioxidant capacity (TAC) in blood were also evaluated.ResultsSignificant increase of LPS (p = 0.0002) and MDA (p = 0.005) concentration was observed in glaucomatous patients as compared with controls. Total SOD activity was significantly lowered in the glaucoma group (p = 0.003); serum level of Mn-SOD was significantly lower in glaucoma patients (p = 0.048) however, Cu,Zn-SOD was not. Glaucoma patients presented elevated mean TOS (p = 0.016). Both groups presented with comparable TAC.ConclusionSystemic redox balance of cataract patients was significantly altered in the course of glaucoma.